drivers/gpu/drm/bridge/ti-sn65dsi86.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Copyright (c) 2018, The Linux Foundation. All rights reserved.
   4  * datasheet: https://www.ti.com/lit/ds/symlink/sn65dsi86.pdf
   5  */
   6
   7 #include <linux/atomic.h>
   8 #include <linux/auxiliary_bus.h>
   9 #include <linux/bitfield.h>
  10 #include <linux/bits.h>
  11 #include <linux/clk.h>
  12 #include <linux/debugfs.h>
  13 #include <linux/gpio/consumer.h>
  14 #include <linux/gpio/driver.h>
  15 #include <linux/i2c.h>
  16 #include <linux/iopoll.h>
  17 #include <linux/module.h>
  18 #include <linux/of_graph.h>
  19 #include <linux/pm_runtime.h>
  20 #include <linux/pwm.h>
  21 #include <linux/regmap.h>
  22 #include <linux/regulator/consumer.h>
  23
  24 #include <asm/unaligned.h>
  25
  26 #include <drm/display/drm_dp_aux_bus.h>
  27 #include <drm/display/drm_dp_helper.h>
  28 #include <drm/drm_atomic.h>
  29 #include <drm/drm_atomic_helper.h>
  30 #include <drm/drm_bridge.h>
  31 #include <drm/drm_bridge_connector.h>
  32 #include <drm/drm_edid.h>
  33 #include <drm/drm_mipi_dsi.h>
  34 #include <drm/drm_of.h>
  35 #include <drm/drm_panel.h>
  36 #include <drm/drm_print.h>
  37 #include <drm/drm_probe_helper.h>
  38
  39 #define SN_DEVICE_REV_REG                       0x08
  40 #define SN_DPPLL_SRC_REG                        0x0A
  41 #define  DPPLL_CLK_SRC_DSICLK                   BIT(0)
  42 #define  REFCLK_FREQ_MASK                       GENMASK(3, 1)
  43 #define  REFCLK_FREQ(x)                         ((x) << 1)
  44 #define  DPPLL_SRC_DP_PLL_LOCK                  BIT(7)
  45 #define SN_PLL_ENABLE_REG                       0x0D
  46 #define SN_DSI_LANES_REG                        0x10
  47 #define  CHA_DSI_LANES_MASK                     GENMASK(4, 3)
  48 #define  CHA_DSI_LANES(x)                       ((x) << 3)
  49 #define SN_DSIA_CLK_FREQ_REG                    0x12
  50 #define SN_CHA_ACTIVE_LINE_LENGTH_LOW_REG       0x20
  51 #define SN_CHA_VERTICAL_DISPLAY_SIZE_LOW_REG    0x24
  52 #define SN_CHA_HSYNC_PULSE_WIDTH_LOW_REG        0x2C
  53 #define SN_CHA_HSYNC_PULSE_WIDTH_HIGH_REG       0x2D
  54 #define  CHA_HSYNC_POLARITY                     BIT(7)
  55 #define SN_CHA_VSYNC_PULSE_WIDTH_LOW_REG        0x30
  56 #define SN_CHA_VSYNC_PULSE_WIDTH_HIGH_REG       0x31
  57 #define  CHA_VSYNC_POLARITY                     BIT(7)
  58 #define SN_CHA_HORIZONTAL_BACK_PORCH_REG        0x34
  59 #define SN_CHA_VERTICAL_BACK_PORCH_REG          0x36
  60 #define SN_CHA_HORIZONTAL_FRONT_PORCH_REG       0x38
  61 #define SN_CHA_VERTICAL_FRONT_PORCH_REG         0x3A
  62 #define SN_LN_ASSIGN_REG                        0x59
  63 #define  LN_ASSIGN_WIDTH                        2
  64 #define SN_ENH_FRAME_REG                        0x5A
  65 #define  VSTREAM_ENABLE                         BIT(3)
  66 #define  LN_POLRS_OFFSET                        4
  67 #define  LN_POLRS_MASK                          0xf0
  68 #define SN_DATA_FORMAT_REG                      0x5B
  69 #define  BPP_18_RGB                             BIT(0)
  70 #define SN_HPD_DISABLE_REG                      0x5C
  71 #define  HPD_DISABLE                            BIT(0)
  72 #define  HPD_DEBOUNCED_STATE                    BIT(4)
  73 #define SN_GPIO_IO_REG                          0x5E
  74 #define  SN_GPIO_INPUT_SHIFT                    4
  75 #define  SN_GPIO_OUTPUT_SHIFT                   0
  76 #define SN_GPIO_CTRL_REG                        0x5F
  77 #define  SN_GPIO_MUX_INPUT                      0
  78 #define  SN_GPIO_MUX_OUTPUT                     1
  79 #define  SN_GPIO_MUX_SPECIAL                    2
  80 #define  SN_GPIO_MUX_MASK                       0x3
  81 #define SN_AUX_WDATA_REG(x)                     (0x64 + (x))
  82 #define SN_AUX_ADDR_19_16_REG                   0x74
  83 #define SN_AUX_ADDR_15_8_REG                    0x75
  84 #define SN_AUX_ADDR_7_0_REG                     0x76
  85 #define SN_AUX_ADDR_MASK                        GENMASK(19, 0)
  86 #define SN_AUX_LENGTH_REG                       0x77
  87 #define SN_AUX_CMD_REG                          0x78
  88 #define  AUX_CMD_SEND                           BIT(0)
  89 #define  AUX_CMD_REQ(x)                         ((x) << 4)
  90 #define SN_AUX_RDATA_REG(x)                     (0x79 + (x))
  91 #define SN_SSC_CONFIG_REG                       0x93
  92 #define  DP_NUM_LANES_MASK                      GENMASK(5, 4)
  93 #define  DP_NUM_LANES(x)                        ((x) << 4)
  94 #define SN_DATARATE_CONFIG_REG                  0x94
  95 #define  DP_DATARATE_MASK                       GENMASK(7, 5)
  96 #define  DP_DATARATE(x)                         ((x) << 5)
  97 #define SN_TRAINING_SETTING_REG                 0x95
  98 #define  SCRAMBLE_DISABLE                       BIT(4)
  99 #define SN_ML_TX_MODE_REG                       0x96
 100 #define  ML_TX_MAIN_LINK_OFF                    0
 101 #define  ML_TX_NORMAL_MODE                      BIT(0)
 102 #define SN_PWM_PRE_DIV_REG                      0xA0
 103 #define SN_BACKLIGHT_SCALE_REG                  0xA1
 104 #define  BACKLIGHT_SCALE_MAX                    0xFFFF
 105 #define SN_BACKLIGHT_REG                        0xA3
 106 #define SN_PWM_EN_INV_REG                       0xA5
 107 #define  SN_PWM_INV_MASK                        BIT(0)
 108 #define  SN_PWM_EN_MASK                         BIT(1)
 109 #define SN_AUX_CMD_STATUS_REG                   0xF4
 110 #define  AUX_IRQ_STATUS_AUX_RPLY_TOUT           BIT(3)
 111 #define  AUX_IRQ_STATUS_AUX_SHORT               BIT(5)
 112 #define  AUX_IRQ_STATUS_NAT_I2C_FAIL            BIT(6)
 113
 114 #define MIN_DSI_CLK_FREQ_MHZ    40
 115
 116 /* fudge factor required to account for 8b/10b encoding */
 117 #define DP_CLK_FUDGE_NUM        10
 118 #define DP_CLK_FUDGE_DEN        8
 119
 120 /* Matches DP_AUX_MAX_PAYLOAD_BYTES (for now) */
 121 #define SN_AUX_MAX_PAYLOAD_BYTES        16
 122
 123 #define SN_REGULATOR_SUPPLY_NUM         4
 124
 125 #define SN_MAX_DP_LANES                 4
 126 #define SN_NUM_GPIOS                    4
 127 #define SN_GPIO_PHYSICAL_OFFSET         1
 128
 129 #define SN_LINK_TRAINING_TRIES          10
 130
 131 #define SN_PWM_GPIO_IDX                 3 /* 4th GPIO */
 132
 133 /**
 134  * struct ti_sn65dsi86 - Platform data for ti-sn65dsi86 driver.
 135  * @bridge_aux:   AUX-bus sub device for MIPI-to-eDP bridge functionality.
 136  * @gpio_aux:     AUX-bus sub device for GPIO controller functionality.
 137  * @aux_aux:      AUX-bus sub device for eDP AUX channel functionality.
 138  * @pwm_aux:      AUX-bus sub device for PWM controller functionality.
 139  *
 140  * @dev:          Pointer to the top level (i2c) device.
 141  * @regmap:       Regmap for accessing i2c.
 142  * @aux:          Our aux channel.
 143  * @bridge:       Our bridge.
 144  * @connector:    Our connector.
 145  * @host_node:    Remote DSI node.
 146  * @dsi:          Our MIPI DSI source.
 147  * @refclk:       Our reference clock.
 148  * @next_bridge:  The bridge on the eDP side.
 149  * @enable_gpio:  The GPIO we toggle to enable the bridge.
 150  * @supplies:     Data for bulk enabling/disabling our regulators.
 151  * @dp_lanes:     Count of dp_lanes we're using.
 152  * @ln_assign:    Value to program to the LN_ASSIGN register.
 153  * @ln_polrs:     Value for the 4-bit LN_POLRS field of SN_ENH_FRAME_REG.
 154  * @comms_enabled: If true then communication over the aux channel is enabled.
 155  * @comms_mutex:   Protects modification of comms_enabled.
 156  *
 157  * @gchip:        If we expose our GPIOs, this is used.
 158  * @gchip_output: A cache of whether we've set GPIOs to output.  This
 159  *                serves double-duty of keeping track of the direction and
 160  *                also keeping track of whether we've incremented the
 161  *                pm_runtime reference count for this pin, which we do
 162  *                whenever a pin is configured as an output.  This is a
 163  *                bitmap so we can do atomic ops on it without an extra
 164  *                lock so concurrent users of our 4 GPIOs don't stomp on
 165  *                each other's read-modify-write.
 166  *
 167  * @pchip:        pwm_chip if the PWM is exposed.
 168  * @pwm_enabled:  Used to track if the PWM signal is currently enabled.
 169  * @pwm_pin_busy: Track if GPIO4 is currently requested for GPIO or PWM.
 170  * @pwm_refclk_freq: Cache for the reference clock input to the PWM.
 171  */
 172 struct ti_sn65dsi86 {
 173         struct auxiliary_device         *bridge_aux;
 174         struct auxiliary_device         *gpio_aux;
 175         struct auxiliary_device         *aux_aux;
 176         struct auxiliary_device         *pwm_aux;
 177
 178         struct device                   *dev;
 179         struct regmap                   *regmap;
 180         struct drm_dp_aux               aux;
 181         struct drm_bridge               bridge;
 182         struct drm_connector            *connector;
 183         struct device_node              *host_node;
 184         struct mipi_dsi_device          *dsi;
 185         struct clk                      *refclk;
 186         struct drm_bridge               *next_bridge;
 187         struct gpio_desc                *enable_gpio;
 188         struct regulator_bulk_data      supplies[SN_REGULATOR_SUPPLY_NUM];
 189         int                             dp_lanes;
 190         u8                              ln_assign;
 191         u8                              ln_polrs;
 192         bool                            comms_enabled;
 193         struct mutex                    comms_mutex;
 194
 195 #if defined(CONFIG_OF_GPIO)
 196         struct gpio_chip                gchip;
 197         DECLARE_BITMAP(gchip_output, SN_NUM_GPIOS);
 198 #endif
 199 #if defined(CONFIG_PWM)
 200         struct pwm_chip                 pchip;
 201         bool                            pwm_enabled;
 202         atomic_t                        pwm_pin_busy;
 203 #endif
 204         unsigned int                    pwm_refclk_freq;
 205 };
 206
 207 static const struct regmap_range ti_sn65dsi86_volatile_ranges[] = {
 208         { .range_min = 0, .range_max = 0xFF },
 209 };
 210
 211 static const struct regmap_access_table ti_sn_bridge_volatile_table = {
 212         .yes_ranges = ti_sn65dsi86_volatile_ranges,
 213         .n_yes_ranges = ARRAY_SIZE(ti_sn65dsi86_volatile_ranges),
 214 };
 215
 216 static const struct regmap_config ti_sn65dsi86_regmap_config = {
 217         .reg_bits = 8,
 218         .val_bits = 8,
 219         .volatile_table = &ti_sn_bridge_volatile_table,
 220         .cache_type = REGCACHE_NONE,
 221         .max_register = 0xFF,
 222 };
 223
 224 static int __maybe_unused ti_sn65dsi86_read_u16(struct ti_sn65dsi86 *pdata,
 225                                                 unsigned int reg, u16 *val)
 226 {
 227         u8 buf[2];
 228         int ret;
 229
 230         ret = regmap_bulk_read(pdata->regmap, reg, buf, ARRAY_SIZE(buf));
 231         if (ret)
 232                 return ret;
 233
 234         *val = buf[0] | (buf[1] << 8);
 235
 236         return 0;
 237 }
 238
 239 static void ti_sn65dsi86_write_u16(struct ti_sn65dsi86 *pdata,
 240                                    unsigned int reg, u16 val)
 241 {
 242         u8 buf[2] = { val & 0xff, val >> 8 };
 243
 244         regmap_bulk_write(pdata->regmap, reg, buf, ARRAY_SIZE(buf));
 245 }
 246
 247 static u32 ti_sn_bridge_get_dsi_freq(struct ti_sn65dsi86 *pdata)
 248 {
 249         u32 bit_rate_khz, clk_freq_khz;
 250         struct drm_display_mode *mode =
 251                 &pdata->bridge.encoder->crtc->state->adjusted_mode;
 252
 253         bit_rate_khz = mode->clock *
 254                         mipi_dsi_pixel_format_to_bpp(pdata->dsi->format);
 255         clk_freq_khz = bit_rate_khz / (pdata->dsi->lanes * 2);
 256
 257         return clk_freq_khz;
 258 }
 259
 260 /* clk frequencies supported by bridge in Hz in case derived from REFCLK pin */
 261 static const u32 ti_sn_bridge_refclk_lut[] = {
 262         12000000,
 263         19200000,
 264         26000000,
 265         27000000,
 266         38400000,
 267 };
 268
 269 /* clk frequencies supported by bridge in Hz in case derived from DACP/N pin */
 270 static const u32 ti_sn_bridge_dsiclk_lut[] = {
 271         468000000,
 272         384000000,
 273         416000000,
 274         486000000,
 275         460800000,
 276 };
 277
 278 static void ti_sn_bridge_set_refclk_freq(struct ti_sn65dsi86 *pdata)
 279 {
 280         int i;
 281         u32 refclk_rate;
 282         const u32 *refclk_lut;
 283         size_t refclk_lut_size;
 284
 285         if (pdata->refclk) {
 286                 refclk_rate = clk_get_rate(pdata->refclk);
 287                 refclk_lut = ti_sn_bridge_refclk_lut;
 288                 refclk_lut_size = ARRAY_SIZE(ti_sn_bridge_refclk_lut);
 289                 clk_prepare_enable(pdata->refclk);
 290         } else {
 291                 refclk_rate = ti_sn_bridge_get_dsi_freq(pdata) * 1000;
 292                 refclk_lut = ti_sn_bridge_dsiclk_lut;
 293                 refclk_lut_size = ARRAY_SIZE(ti_sn_bridge_dsiclk_lut);
 294         }
 295
 296         /* for i equals to refclk_lut_size means default frequency */
 297         for (i = 0; i < refclk_lut_size; i++)
 298                 if (refclk_lut[i] == refclk_rate)
 299                         break;
 300
 301         /* avoid buffer overflow and "1" is the default rate in the datasheet. */
 302         if (i >= refclk_lut_size)
 303                 i = 1;
 304
 305         regmap_update_bits(pdata->regmap, SN_DPPLL_SRC_REG, REFCLK_FREQ_MASK,
 306                            REFCLK_FREQ(i));
 307
 308         /*
 309          * The PWM refclk is based on the value written to SN_DPPLL_SRC_REG,
 310          * regardless of its actual sourcing.
 311          */
 312         pdata->pwm_refclk_freq = ti_sn_bridge_refclk_lut[i];
 313 }
 314
 315 static void ti_sn65dsi86_enable_comms(struct ti_sn65dsi86 *pdata)
 316 {
 317         mutex_lock(&pdata->comms_mutex);
 318
 319         /* configure bridge ref_clk */
 320         ti_sn_bridge_set_refclk_freq(pdata);
 321
 322         /*
 323          * HPD on this bridge chip is a bit useless.  This is an eDP bridge
 324          * so the HPD is an internal signal that's only there to signal that
 325          * the panel is done powering up.  ...but the bridge chip debounces
 326          * this signal by between 100 ms and 400 ms (depending on process,
 327          * voltage, and temperate--I measured it at about 200 ms).  One
 328          * particular panel asserted HPD 84 ms after it was powered on meaning
 329          * that we saw HPD 284 ms after power on.  ...but the same panel said
 330          * that instead of looking at HPD you could just hardcode a delay of
 331          * 200 ms.  We'll assume that the panel driver will have the hardcoded
 332          * delay in its prepare and always disable HPD.
 333          *
 334          * If HPD somehow makes sense on some future panel we'll have to
 335          * change this to be conditional on someone specifying that HPD should
 336          * be used.
 337          */
 338         regmap_update_bits(pdata->regmap, SN_HPD_DISABLE_REG, HPD_DISABLE,
 339                            HPD_DISABLE);
 340
 341         pdata->comms_enabled = true;
 342
 343         mutex_unlock(&pdata->comms_mutex);
 344 }
 345
 346 static void ti_sn65dsi86_disable_comms(struct ti_sn65dsi86 *pdata)
 347 {
 348         mutex_lock(&pdata->comms_mutex);
 349
 350         pdata->comms_enabled = false;
 351         clk_disable_unprepare(pdata->refclk);
 352
 353         mutex_unlock(&pdata->comms_mutex);
 354 }
 355
 356 static int __maybe_unused ti_sn65dsi86_resume(struct device *dev)
 357 {
 358         struct ti_sn65dsi86 *pdata = dev_get_drvdata(dev);
 359         int ret;
 360
 361         ret = regulator_bulk_enable(SN_REGULATOR_SUPPLY_NUM, pdata->supplies);
 362         if (ret) {
 363                 DRM_ERROR("failed to enable supplies %d\n", ret);
 364                 return ret;
 365         }
 366
 367         /* td2: min 100 us after regulators before enabling the GPIO */
 368         usleep_range(100, 110);
 369
 370         gpiod_set_value_cansleep(pdata->enable_gpio, 1);
 371
 372         /*
 373          * If we have a reference clock we can enable communication w/ the
 374          * panel (including the aux channel) w/out any need for an input clock
 375          * so we can do it in resume which lets us read the EDID before
 376          * pre_enable(). Without a reference clock we need the MIPI reference
 377          * clock so reading early doesn't work.
 378          */
 379         if (pdata->refclk)
 380                 ti_sn65dsi86_enable_comms(pdata);
 381
 382         return ret;
 383 }
 384
 385 static int __maybe_unused ti_sn65dsi86_suspend(struct device *dev)
 386 {
 387         struct ti_sn65dsi86 *pdata = dev_get_drvdata(dev);
 388         int ret;
 389
 390         if (pdata->refclk)
 391                 ti_sn65dsi86_disable_comms(pdata);
 392
 393         gpiod_set_value_cansleep(pdata->enable_gpio, 0);
 394
 395         ret = regulator_bulk_disable(SN_REGULATOR_SUPPLY_NUM, pdata->supplies);
 396         if (ret)
 397                 DRM_ERROR("failed to disable supplies %d\n", ret);
 398
 399         return ret;
 400 }
 401
 402 static const struct dev_pm_ops ti_sn65dsi86_pm_ops = {
 403         SET_RUNTIME_PM_OPS(ti_sn65dsi86_suspend, ti_sn65dsi86_resume, NULL)
 404         SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
 405                                 pm_runtime_force_resume)
 406 };
 407
 408 static int status_show(struct seq_file *s, void *data)
 409 {
 410         struct ti_sn65dsi86 *pdata = s->private;
 411         unsigned int reg, val;
 412
 413         seq_puts(s, "STATUS REGISTERS:\n");
 414
 415         pm_runtime_get_sync(pdata->dev);
 416
 417         /* IRQ Status Registers, see Table 31 in datasheet */
 418         for (reg = 0xf0; reg <= 0xf8; reg++) {
 419                 regmap_read(pdata->regmap, reg, &val);
 420                 seq_printf(s, "[0x%02x] = 0x%08x\n", reg, val);
 421         }
 422
 423         pm_runtime_put_autosuspend(pdata->dev);
 424
 425         return 0;
 426 }
 427
 428 DEFINE_SHOW_ATTRIBUTE(status);
 429
 430 static void ti_sn65dsi86_debugfs_remove(void *data)
 431 {
 432         debugfs_remove_recursive(data);
 433 }
 434
 435 static void ti_sn65dsi86_debugfs_init(struct ti_sn65dsi86 *pdata)
 436 {
 437         struct device *dev = pdata->dev;
 438         struct dentry *debugfs;
 439         int ret;
 440
 441         debugfs = debugfs_create_dir(dev_name(dev), NULL);
 442
 443         /*
 444          * We might get an error back if debugfs wasn't enabled in the kernel
 445          * so let's just silently return upon failure.
 446          */
 447         if (IS_ERR_OR_NULL(debugfs))
 448                 return;
 449
 450         ret = devm_add_action_or_reset(dev, ti_sn65dsi86_debugfs_remove, debugfs);
 451         if (ret)
 452                 return;
 453
 454         debugfs_create_file("status", 0600, debugfs, pdata, &status_fops);
 455 }
 456
 457 /* -----------------------------------------------------------------------------
 458  * Auxiliary Devices (*not* AUX)
 459  */
 460
 461 static void ti_sn65dsi86_uninit_aux(void *data)
 462 {
 463         auxiliary_device_uninit(data);
 464 }
 465
 466 static void ti_sn65dsi86_delete_aux(void *data)
 467 {
 468         auxiliary_device_delete(data);
 469 }
 470
 471 static void ti_sn65dsi86_aux_device_release(struct device *dev)
 472 {
 473         struct auxiliary_device *aux = container_of(dev, struct auxiliary_device, dev);
 474
 475         kfree(aux);
 476 }
 477
 478 static int ti_sn65dsi86_add_aux_device(struct ti_sn65dsi86 *pdata,
 479                                        struct auxiliary_device **aux_out,
 480                                        const char *name)
 481 {
 482         struct device *dev = pdata->dev;
 483         struct auxiliary_device *aux;
 484         int ret;
 485
 486         aux = kzalloc(sizeof(*aux), GFP_KERNEL);
 487         if (!aux)
 488                 return -ENOMEM;
 489
 490         aux->name = name;
 491         aux->dev.parent = dev;
 492         aux->dev.release = ti_sn65dsi86_aux_device_release;
 493         device_set_of_node_from_dev(&aux->dev, dev);
 494         ret = auxiliary_device_init(aux);
 495         if (ret) {
 496                 kfree(aux);
 497                 return ret;
 498         }
 499         ret = devm_add_action_or_reset(dev, ti_sn65dsi86_uninit_aux, aux);
 500         if (ret)
 501                 return ret;
 502
 503         ret = auxiliary_device_add(aux);
 504         if (ret)
 505                 return ret;
 506         ret = devm_add_action_or_reset(dev, ti_sn65dsi86_delete_aux, aux);
 507         if (!ret)
 508                 *aux_out = aux;
 509
 510         return ret;
 511 }
 512
 513 /* -----------------------------------------------------------------------------
 514  * AUX Adapter
 515  */
 516
 517 static struct ti_sn65dsi86 *aux_to_ti_sn65dsi86(struct drm_dp_aux *aux)
 518 {
 519         return container_of(aux, struct ti_sn65dsi86, aux);
 520 }
 521
 522 static ssize_t ti_sn_aux_transfer(struct drm_dp_aux *aux,
 523                                   struct drm_dp_aux_msg *msg)
 524 {
 525         struct ti_sn65dsi86 *pdata = aux_to_ti_sn65dsi86(aux);
 526         u32 request = msg->request & ~(DP_AUX_I2C_MOT | DP_AUX_I2C_WRITE_STATUS_UPDATE);
 527         u32 request_val = AUX_CMD_REQ(msg->request);
 528         u8 *buf = msg->buffer;
 529         unsigned int len = msg->size;
 530         unsigned int short_len;
 531         unsigned int val;
 532         int ret;
 533         u8 addr_len[SN_AUX_LENGTH_REG + 1 - SN_AUX_ADDR_19_16_REG];
 534
 535         if (len > SN_AUX_MAX_PAYLOAD_BYTES)
 536                 return -EINVAL;
 537
 538         pm_runtime_get_sync(pdata->dev);
 539         mutex_lock(&pdata->comms_mutex);
 540
 541         /*
 542          * If someone tries to do a DDC over AUX transaction before pre_enable()
 543          * on a device without a dedicated reference clock then we just can't
 544          * do it. Fail right away. This prevents non-refclk users from reading
 545          * the EDID before enabling the panel but such is life.
 546          */
 547         if (!pdata->comms_enabled) {
 548                 ret = -EIO;
 549                 goto exit;
 550         }
 551
 552         switch (request) {
 553         case DP_AUX_NATIVE_WRITE:
 554         case DP_AUX_I2C_WRITE:
 555         case DP_AUX_NATIVE_READ:
 556         case DP_AUX_I2C_READ:
 557                 regmap_write(pdata->regmap, SN_AUX_CMD_REG, request_val);
 558                 /* Assume it's good */
 559                 msg->reply = 0;
 560                 break;
 561         default:
 562                 ret = -EINVAL;
 563                 goto exit;
 564         }
 565
 566         BUILD_BUG_ON(sizeof(addr_len) != sizeof(__be32));
 567         put_unaligned_be32((msg->address & SN_AUX_ADDR_MASK) << 8 | len,
 568                            addr_len);
 569         regmap_bulk_write(pdata->regmap, SN_AUX_ADDR_19_16_REG, addr_len,
 570                           ARRAY_SIZE(addr_len));
 571
 572         if (request == DP_AUX_NATIVE_WRITE || request == DP_AUX_I2C_WRITE)
 573                 regmap_bulk_write(pdata->regmap, SN_AUX_WDATA_REG(0), buf, len);
 574
 575         /* Clear old status bits before start so we don't get confused */
 576         regmap_write(pdata->regmap, SN_AUX_CMD_STATUS_REG,
 577                      AUX_IRQ_STATUS_NAT_I2C_FAIL |
 578                      AUX_IRQ_STATUS_AUX_RPLY_TOUT |
 579                      AUX_IRQ_STATUS_AUX_SHORT);
 580
 581         regmap_write(pdata->regmap, SN_AUX_CMD_REG, request_val | AUX_CMD_SEND);
 582
 583         /* Zero delay loop because i2c transactions are slow already */
 584         ret = regmap_read_poll_timeout(pdata->regmap, SN_AUX_CMD_REG, val,
 585                                        !(val & AUX_CMD_SEND), 0, 50 * 1000);
 586         if (ret)
 587                 goto exit;
 588
 589         ret = regmap_read(pdata->regmap, SN_AUX_CMD_STATUS_REG, &val);
 590         if (ret)
 591                 goto exit;
 592
 593         if (val & AUX_IRQ_STATUS_AUX_RPLY_TOUT) {
 594                 /*
 595                  * The hardware tried the message seven times per the DP spec
 596                  * but it hit a timeout. We ignore defers here because they're
 597                  * handled in hardware.
 598                  */
 599                 ret = -ETIMEDOUT;
 600                 goto exit;
 601         }
 602
 603         if (val & AUX_IRQ_STATUS_AUX_SHORT) {
 604                 ret = regmap_read(pdata->regmap, SN_AUX_LENGTH_REG, &short_len);
 605                 len = min(len, short_len);
 606                 if (ret)
 607                         goto exit;
 608         } else if (val & AUX_IRQ_STATUS_NAT_I2C_FAIL) {
 609                 switch (request) {
 610                 case DP_AUX_I2C_WRITE:
 611                 case DP_AUX_I2C_READ:
 612                         msg->reply |= DP_AUX_I2C_REPLY_NACK;
 613                         break;
 614                 case DP_AUX_NATIVE_READ:
 615                 case DP_AUX_NATIVE_WRITE:
 616                         msg->reply |= DP_AUX_NATIVE_REPLY_NACK;
 617                         break;
 618                 }
 619                 len = 0;
 620                 goto exit;
 621         }
 622
 623         if (request != DP_AUX_NATIVE_WRITE && request != DP_AUX_I2C_WRITE && len != 0)
 624                 ret = regmap_bulk_read(pdata->regmap, SN_AUX_RDATA_REG(0), buf, len);
 625
 626 exit:
 627         mutex_unlock(&pdata->comms_mutex);
 628         pm_runtime_mark_last_busy(pdata->dev);
 629         pm_runtime_put_autosuspend(pdata->dev);
 630
 631         if (ret)
 632                 return ret;
 633         return len;
 634 }
 635
 636 static int ti_sn_aux_wait_hpd_asserted(struct drm_dp_aux *aux, unsigned long wait_us)
 637 {
 638         /*
 639          * The HPD in this chip is a bit useless (See comment in
 640          * ti_sn65dsi86_enable_comms) so if our driver is expected to wait
 641          * for HPD, we just assume it's asserted after the wait_us delay.
 642          *
 643          * In case we are asked to wait forever (wait_us=0) take conservative
 644          * 500ms delay.
 645          */
 646         if (wait_us == 0)
 647                 wait_us = 500000;
 648
 649         usleep_range(wait_us, wait_us + 1000);
 650
 651         return 0;
 652 }
 653
 654 static int ti_sn_aux_probe(struct auxiliary_device *adev,
 655                            const struct auxiliary_device_id *id)
 656 {
 657         struct ti_sn65dsi86 *pdata = dev_get_drvdata(adev->dev.parent);
 658         int ret;
 659
 660         pdata->aux.name = "ti-sn65dsi86-aux";
 661         pdata->aux.dev = &adev->dev;
 662         pdata->aux.transfer = ti_sn_aux_transfer;
 663         pdata->aux.wait_hpd_asserted = ti_sn_aux_wait_hpd_asserted;
 664         drm_dp_aux_init(&pdata->aux);
 665
 666         ret = devm_of_dp_aux_populate_ep_devices(&pdata->aux);
 667         if (ret)
 668                 return ret;
 669
 670         /*
 671          * The eDP to MIPI bridge parts don't work until the AUX channel is
 672          * setup so we don't add it in the main driver probe, we add it now.
 673          */
 674         return ti_sn65dsi86_add_aux_device(pdata, &pdata->bridge_aux, "bridge");
 675 }
 676
 677 static const struct auxiliary_device_id ti_sn_aux_id_table[] = {
 678         { .name = "ti_sn65dsi86.aux", },
 679         {},
 680 };
 681
 682 static struct auxiliary_driver ti_sn_aux_driver = {
 683         .name = "aux",
 684         .probe = ti_sn_aux_probe,
 685         .id_table = ti_sn_aux_id_table,
 686 };
 687
 688 /*------------------------------------------------------------------------------
 689  * DRM Bridge
 690  */
 691
 692 static struct ti_sn65dsi86 *bridge_to_ti_sn65dsi86(struct drm_bridge *bridge)
 693 {
 694         return container_of(bridge, struct ti_sn65dsi86, bridge);
 695 }
 696
 697 static int ti_sn_attach_host(struct auxiliary_device *adev, struct ti_sn65dsi86 *pdata)
 698 {
 699         int val;
 700         struct mipi_dsi_host *host;
 701         struct mipi_dsi_device *dsi;
 702         struct device *dev = pdata->dev;
 703         const struct mipi_dsi_device_info info = { .type = "ti_sn_bridge",
 704                                                    .channel = 0,
 705                                                    .node = NULL,
 706         };
 707
 708         host = of_find_mipi_dsi_host_by_node(pdata->host_node);
 709         if (!host)
 710                 return -EPROBE_DEFER;
 711
 712         dsi = devm_mipi_dsi_device_register_full(&adev->dev, host, &info);
 713         if (IS_ERR(dsi))
 714                 return PTR_ERR(dsi);
 715
 716         /* TODO: setting to 4 MIPI lanes always for now */
 717         dsi->lanes = 4;
 718         dsi->format = MIPI_DSI_FMT_RGB888;
 719         dsi->mode_flags = MIPI_DSI_MODE_VIDEO;
 720
 721         /* check if continuous dsi clock is required or not */
 722         pm_runtime_get_sync(dev);
 723         regmap_read(pdata->regmap, SN_DPPLL_SRC_REG, &val);
 724         pm_runtime_put_autosuspend(dev);
 725         if (!(val & DPPLL_CLK_SRC_DSICLK))
 726                 dsi->mode_flags |= MIPI_DSI_CLOCK_NON_CONTINUOUS;
 727
 728         pdata->dsi = dsi;
 729
 730         return devm_mipi_dsi_attach(&adev->dev, dsi);
 731 }
 732
 733 static int ti_sn_bridge_attach(struct drm_bridge *bridge,
 734                                enum drm_bridge_attach_flags flags)
 735 {
 736         struct ti_sn65dsi86 *pdata = bridge_to_ti_sn65dsi86(bridge);
 737         int ret;
 738
 739         pdata->aux.drm_dev = bridge->dev;
 740         ret = drm_dp_aux_register(&pdata->aux);
 741         if (ret < 0) {
 742                 drm_err(bridge->dev, "Failed to register DP AUX channel: %d\n", ret);
 743                 return ret;
 744         }
 745
 746         /*
 747          * Attach the next bridge.
 748          * We never want the next bridge to *also* create a connector.
 749          */
 750         ret = drm_bridge_attach(bridge->encoder, pdata->next_bridge,
 751                                 &pdata->bridge, flags | DRM_BRIDGE_ATTACH_NO_CONNECTOR);
 752         if (ret < 0)
 753                 goto err_initted_aux;
 754
 755         if (flags & DRM_BRIDGE_ATTACH_NO_CONNECTOR)
 756                 return 0;
 757
 758         pdata->connector = drm_bridge_connector_init(pdata->bridge.dev,
 759                                                      pdata->bridge.encoder);
 760         if (IS_ERR(pdata->connector)) {
 761                 ret = PTR_ERR(pdata->connector);
 762                 goto err_initted_aux;
 763         }
 764
 765         drm_connector_attach_encoder(pdata->connector, pdata->bridge.encoder);
 766
 767         return 0;
 768
 769 err_initted_aux:
 770         drm_dp_aux_unregister(&pdata->aux);
 771         return ret;
 772 }
 773
 774 static void ti_sn_bridge_detach(struct drm_bridge *bridge)
 775 {
 776         drm_dp_aux_unregister(&bridge_to_ti_sn65dsi86(bridge)->aux);
 777 }
 778
 779 static enum drm_mode_status
 780 ti_sn_bridge_mode_valid(struct drm_bridge *bridge,
 781                         const struct drm_display_info *info,
 782                         const struct drm_display_mode *mode)
 783 {
 784         /* maximum supported resolution is 4K at 60 fps */
 785         if (mode->clock > 594000)
 786                 return MODE_CLOCK_HIGH;
 787
 788         /*
 789          * The front and back porch registers are 8 bits, and pulse width
 790          * registers are 15 bits, so reject any modes with larger periods.
 791          */
 792
 793         if ((mode->hsync_start - mode->hdisplay) > 0xff)
 794                 return MODE_HBLANK_WIDE;
 795
 796         if ((mode->vsync_start - mode->vdisplay) > 0xff)
 797                 return MODE_VBLANK_WIDE;
 798
 799         if ((mode->hsync_end - mode->hsync_start) > 0x7fff)
 800                 return MODE_HSYNC_WIDE;
 801
 802         if ((mode->vsync_end - mode->vsync_start) > 0x7fff)
 803                 return MODE_VSYNC_WIDE;
 804
 805         if ((mode->htotal - mode->hsync_end) > 0xff)
 806                 return MODE_HBLANK_WIDE;
 807
 808         if ((mode->vtotal - mode->vsync_end) > 0xff)
 809                 return MODE_VBLANK_WIDE;
 810
 811         return MODE_OK;
 812 }
 813
 814 static void ti_sn_bridge_atomic_disable(struct drm_bridge *bridge,
 815                                         struct drm_bridge_state *old_bridge_state)
 816 {
 817         struct ti_sn65dsi86 *pdata = bridge_to_ti_sn65dsi86(bridge);
 818
 819         /* disable video stream */
 820         regmap_update_bits(pdata->regmap, SN_ENH_FRAME_REG, VSTREAM_ENABLE, 0);
 821 }
 822
 823 static void ti_sn_bridge_set_dsi_rate(struct ti_sn65dsi86 *pdata)
 824 {
 825         unsigned int bit_rate_mhz, clk_freq_mhz;
 826         unsigned int val;
 827         struct drm_display_mode *mode =
 828                 &pdata->bridge.encoder->crtc->state->adjusted_mode;
 829
 830         /* set DSIA clk frequency */
 831         bit_rate_mhz = (mode->clock / 1000) *
 832                         mipi_dsi_pixel_format_to_bpp(pdata->dsi->format);
 833         clk_freq_mhz = bit_rate_mhz / (pdata->dsi->lanes * 2);
 834
 835         /* for each increment in val, frequency increases by 5MHz */
 836         val = (MIN_DSI_CLK_FREQ_MHZ / 5) +
 837                 (((clk_freq_mhz - MIN_DSI_CLK_FREQ_MHZ) / 5) & 0xFF);
 838         regmap_write(pdata->regmap, SN_DSIA_CLK_FREQ_REG, val);
 839 }
 840
 841 static unsigned int ti_sn_bridge_get_bpp(struct drm_connector *connector)
 842 {
 843         if (connector->display_info.bpc <= 6)
 844                 return 18;
 845         else
 846                 return 24;
 847 }
 848
 849 /*
 850  * LUT index corresponds to register value and
 851  * LUT values corresponds to dp data rate supported
 852  * by the bridge in Mbps unit.
 853  */
 854 static const unsigned int ti_sn_bridge_dp_rate_lut[] = {
 855         0, 1620, 2160, 2430, 2700, 3240, 4320, 5400
 856 };
 857
 858 static int ti_sn_bridge_calc_min_dp_rate_idx(struct ti_sn65dsi86 *pdata, unsigned int bpp)
 859 {
 860         unsigned int bit_rate_khz, dp_rate_mhz;
 861         unsigned int i;
 862         struct drm_display_mode *mode =
 863                 &pdata->bridge.encoder->crtc->state->adjusted_mode;
 864
 865         /* Calculate minimum bit rate based on our pixel clock. */
 866         bit_rate_khz = mode->clock * bpp;
 867
 868         /* Calculate minimum DP data rate, taking 80% as per DP spec */
 869         dp_rate_mhz = DIV_ROUND_UP(bit_rate_khz * DP_CLK_FUDGE_NUM,
 870                                    1000 * pdata->dp_lanes * DP_CLK_FUDGE_DEN);
 871
 872         for (i = 1; i < ARRAY_SIZE(ti_sn_bridge_dp_rate_lut) - 1; i++)
 873                 if (ti_sn_bridge_dp_rate_lut[i] >= dp_rate_mhz)
 874                         break;
 875
 876         return i;
 877 }
 878
 879 static unsigned int ti_sn_bridge_read_valid_rates(struct ti_sn65dsi86 *pdata)
 880 {
 881         unsigned int valid_rates = 0;
 882         unsigned int rate_per_200khz;
 883         unsigned int rate_mhz;
 884         u8 dpcd_val;
 885         int ret;
 886         int i, j;
 887
 888         ret = drm_dp_dpcd_readb(&pdata->aux, DP_EDP_DPCD_REV, &dpcd_val);
 889         if (ret != 1) {
 890                 DRM_DEV_ERROR(pdata->dev,
 891                               "Can't read eDP rev (%d), assuming 1.1\n", ret);
 892                 dpcd_val = DP_EDP_11;
 893         }
 894
 895         if (dpcd_val >= DP_EDP_14) {
 896                 /* eDP 1.4 devices must provide a custom table */
 897                 __le16 sink_rates[DP_MAX_SUPPORTED_RATES];
 898
 899                 ret = drm_dp_dpcd_read(&pdata->aux, DP_SUPPORTED_LINK_RATES,
 900                                        sink_rates, sizeof(sink_rates));
 901
 902                 if (ret != sizeof(sink_rates)) {
 903                         DRM_DEV_ERROR(pdata->dev,
 904                                 "Can't read supported rate table (%d)\n", ret);
 905
 906                         /* By zeroing we'll fall back to DP_MAX_LINK_RATE. */
 907                         memset(sink_rates, 0, sizeof(sink_rates));
 908                 }
 909
 910                 for (i = 0; i < ARRAY_SIZE(sink_rates); i++) {
 911                         rate_per_200khz = le16_to_cpu(sink_rates[i]);
 912
 913                         if (!rate_per_200khz)
 914                                 break;
 915
 916                         rate_mhz = rate_per_200khz * 200 / 1000;
 917                         for (j = 0;
 918                              j < ARRAY_SIZE(ti_sn_bridge_dp_rate_lut);
 919                              j++) {
 920                                 if (ti_sn_bridge_dp_rate_lut[j] == rate_mhz)
 921                                         valid_rates |= BIT(j);
 922                         }
 923                 }
 924
 925                 for (i = 0; i < ARRAY_SIZE(ti_sn_bridge_dp_rate_lut); i++) {
 926                         if (valid_rates & BIT(i))
 927                                 return valid_rates;
 928                 }
 929                 DRM_DEV_ERROR(pdata->dev,
 930                               "No matching eDP rates in table; falling back\n");
 931         }
 932
 933         /* On older versions best we can do is use DP_MAX_LINK_RATE */
 934         ret = drm_dp_dpcd_readb(&pdata->aux, DP_MAX_LINK_RATE, &dpcd_val);
 935         if (ret != 1) {
 936                 DRM_DEV_ERROR(pdata->dev,
 937                               "Can't read max rate (%d); assuming 5.4 GHz\n",
 938                               ret);
 939                 dpcd_val = DP_LINK_BW_5_4;
 940         }
 941
 942         switch (dpcd_val) {
 943         default:
 944                 DRM_DEV_ERROR(pdata->dev,
 945                               "Unexpected max rate (%#x); assuming 5.4 GHz\n",
 946                               (int)dpcd_val);
 947                 fallthrough;
 948         case DP_LINK_BW_5_4:
 949                 valid_rates |= BIT(7);
 950                 fallthrough;
 951         case DP_LINK_BW_2_7:
 952                 valid_rates |= BIT(4);
 953                 fallthrough;
 954         case DP_LINK_BW_1_62:
 955                 valid_rates |= BIT(1);
 956                 break;
 957         }
 958
 959         return valid_rates;
 960 }
 961
 962 static void ti_sn_bridge_set_video_timings(struct ti_sn65dsi86 *pdata)
 963 {
 964         struct drm_display_mode *mode =
 965                 &pdata->bridge.encoder->crtc->state->adjusted_mode;
 966         u8 hsync_polarity = 0, vsync_polarity = 0;
 967
 968         if (mode->flags & DRM_MODE_FLAG_NHSYNC)
 969                 hsync_polarity = CHA_HSYNC_POLARITY;
 970         if (mode->flags & DRM_MODE_FLAG_NVSYNC)
 971                 vsync_polarity = CHA_VSYNC_POLARITY;
 972
 973         ti_sn65dsi86_write_u16(pdata, SN_CHA_ACTIVE_LINE_LENGTH_LOW_REG,
 974                                mode->hdisplay);
 975         ti_sn65dsi86_write_u16(pdata, SN_CHA_VERTICAL_DISPLAY_SIZE_LOW_REG,
 976                                mode->vdisplay);
 977         regmap_write(pdata->regmap, SN_CHA_HSYNC_PULSE_WIDTH_LOW_REG,
 978                      (mode->hsync_end - mode->hsync_start) & 0xFF);
 979         regmap_write(pdata->regmap, SN_CHA_HSYNC_PULSE_WIDTH_HIGH_REG,
 980                      (((mode->hsync_end - mode->hsync_start) >> 8) & 0x7F) |
 981                      hsync_polarity);
 982         regmap_write(pdata->regmap, SN_CHA_VSYNC_PULSE_WIDTH_LOW_REG,
 983                      (mode->vsync_end - mode->vsync_start) & 0xFF);
 984         regmap_write(pdata->regmap, SN_CHA_VSYNC_PULSE_WIDTH_HIGH_REG,
 985                      (((mode->vsync_end - mode->vsync_start) >> 8) & 0x7F) |
 986                      vsync_polarity);
 987
 988         regmap_write(pdata->regmap, SN_CHA_HORIZONTAL_BACK_PORCH_REG,
 989                      (mode->htotal - mode->hsync_end) & 0xFF);
 990         regmap_write(pdata->regmap, SN_CHA_VERTICAL_BACK_PORCH_REG,
 991                      (mode->vtotal - mode->vsync_end) & 0xFF);
 992
 993         regmap_write(pdata->regmap, SN_CHA_HORIZONTAL_FRONT_PORCH_REG,
 994                      (mode->hsync_start - mode->hdisplay) & 0xFF);
 995         regmap_write(pdata->regmap, SN_CHA_VERTICAL_FRONT_PORCH_REG,
 996                      (mode->vsync_start - mode->vdisplay) & 0xFF);
 997
 998         usleep_range(10000, 10500); /* 10ms delay recommended by spec */
 999 }
1000
1001 static unsigned int ti_sn_get_max_lanes(struct ti_sn65dsi86 *pdata)
1002 {
1003         u8 data;
1004         int ret;
1005
1006         ret = drm_dp_dpcd_readb(&pdata->aux, DP_MAX_LANE_COUNT, &data);
1007         if (ret != 1) {
1008                 DRM_DEV_ERROR(pdata->dev,
1009                               "Can't read lane count (%d); assuming 4\n", ret);
1010                 return 4;
1011         }
1012
1013         return data & DP_LANE_COUNT_MASK;
1014 }
1015
1016 static int ti_sn_link_training(struct ti_sn65dsi86 *pdata, int dp_rate_idx,
1017                                const char **last_err_str)
1018 {
1019         unsigned int val;
1020         int ret;
1021         int i;
1022
1023         /* set dp clk frequency value */
1024         regmap_update_bits(pdata->regmap, SN_DATARATE_CONFIG_REG,
1025                            DP_DATARATE_MASK, DP_DATARATE(dp_rate_idx));
1026
1027         /* enable DP PLL */
1028         regmap_write(pdata->regmap, SN_PLL_ENABLE_REG, 1);
1029
1030         ret = regmap_read_poll_timeout(pdata->regmap, SN_DPPLL_SRC_REG, val,
1031                                        val & DPPLL_SRC_DP_PLL_LOCK, 1000,
1032                                        50 * 1000);
1033         if (ret) {
1034                 *last_err_str = "DP_PLL_LOCK polling failed";
1035                 goto exit;
1036         }
1037
1038         /*
1039          * We'll try to link train several times.  As part of link training
1040          * the bridge chip will write DP_SET_POWER_D0 to DP_SET_POWER.  If
1041          * the panel isn't ready quite it might respond NAK here which means
1042          * we need to try again.
1043          */
1044         for (i = 0; i < SN_LINK_TRAINING_TRIES; i++) {
1045                 /* Semi auto link training mode */
1046                 regmap_write(pdata->regmap, SN_ML_TX_MODE_REG, 0x0A);
1047                 ret = regmap_read_poll_timeout(pdata->regmap, SN_ML_TX_MODE_REG, val,
1048                                                val == ML_TX_MAIN_LINK_OFF ||
1049                                                val == ML_TX_NORMAL_MODE, 1000,
1050                                                500 * 1000);
1051                 if (ret) {
1052                         *last_err_str = "Training complete polling failed";
1053                 } else if (val == ML_TX_MAIN_LINK_OFF) {
1054                         *last_err_str = "Link training failed, link is off";
1055                         ret = -EIO;
1056                         continue;
1057                 }
1058
1059                 break;
1060         }
1061
1062         /* If we saw quite a few retries, add a note about it */
1063         if (!ret && i > SN_LINK_TRAINING_TRIES / 2)
1064                 DRM_DEV_INFO(pdata->dev, "Link training needed %d retries\n", i);
1065
1066 exit:
1067         /* Disable the PLL if we failed */
1068         if (ret)
1069                 regmap_write(pdata->regmap, SN_PLL_ENABLE_REG, 0);
1070
1071         return ret;
1072 }
1073
1074 static void ti_sn_bridge_atomic_enable(struct drm_bridge *bridge,
1075                                        struct drm_bridge_state *old_bridge_state)
1076 {
1077         struct ti_sn65dsi86 *pdata = bridge_to_ti_sn65dsi86(bridge);
1078         struct drm_connector *connector;
1079         const char *last_err_str = "No supported DP rate";
1080         unsigned int valid_rates;
1081         int dp_rate_idx;
1082         unsigned int val;
1083         int ret = -EINVAL;
1084         int max_dp_lanes;
1085         unsigned int bpp;
1086
1087         connector = drm_atomic_get_new_connector_for_encoder(old_bridge_state->base.state,
1088                                                              bridge->encoder);
1089         if (!connector) {
1090                 dev_err_ratelimited(pdata->dev, "Could not get the connector\n");
1091                 return;
1092         }
1093
1094         max_dp_lanes = ti_sn_get_max_lanes(pdata);
1095         pdata->dp_lanes = min(pdata->dp_lanes, max_dp_lanes);
1096
1097         /* DSI_A lane config */
1098         val = CHA_DSI_LANES(SN_MAX_DP_LANES - pdata->dsi->lanes);
1099         regmap_update_bits(pdata->regmap, SN_DSI_LANES_REG,
1100                            CHA_DSI_LANES_MASK, val);
1101
1102         regmap_write(pdata->regmap, SN_LN_ASSIGN_REG, pdata->ln_assign);
1103         regmap_update_bits(pdata->regmap, SN_ENH_FRAME_REG, LN_POLRS_MASK,
1104                            pdata->ln_polrs << LN_POLRS_OFFSET);
1105
1106         /* set dsi clk frequency value */
1107         ti_sn_bridge_set_dsi_rate(pdata);
1108
1109         /*
1110          * The SN65DSI86 only supports ASSR Display Authentication method and
1111          * this method is enabled for eDP panels. An eDP panel must support this
1112          * authentication method. We need to enable this method in the eDP panel
1113          * at DisplayPort address 0x0010A prior to link training.
1114          *
1115          * As only ASSR is supported by SN65DSI86, for full DisplayPort displays
1116          * we need to disable the scrambler.
1117          */
1118         if (pdata->bridge.type == DRM_MODE_CONNECTOR_eDP) {
1119                 drm_dp_dpcd_writeb(&pdata->aux, DP_EDP_CONFIGURATION_SET,
1120                                    DP_ALTERNATE_SCRAMBLER_RESET_ENABLE);
1121
1122                 regmap_update_bits(pdata->regmap, SN_TRAINING_SETTING_REG,
1123                                    SCRAMBLE_DISABLE, 0);
1124         } else {
1125                 regmap_update_bits(pdata->regmap, SN_TRAINING_SETTING_REG,
1126                                    SCRAMBLE_DISABLE, SCRAMBLE_DISABLE);
1127         }
1128
1129         bpp = ti_sn_bridge_get_bpp(connector);
1130         /* Set the DP output format (18 bpp or 24 bpp) */
1131         val = bpp == 18 ? BPP_18_RGB : 0;
1132         regmap_update_bits(pdata->regmap, SN_DATA_FORMAT_REG, BPP_18_RGB, val);
1133
1134         /* DP lane config */
1135         val = DP_NUM_LANES(min(pdata->dp_lanes, 3));
1136         regmap_update_bits(pdata->regmap, SN_SSC_CONFIG_REG, DP_NUM_LANES_MASK,
1137                            val);
1138
1139         valid_rates = ti_sn_bridge_read_valid_rates(pdata);
1140
1141         /* Train until we run out of rates */
1142         for (dp_rate_idx = ti_sn_bridge_calc_min_dp_rate_idx(pdata, bpp);
1143              dp_rate_idx < ARRAY_SIZE(ti_sn_bridge_dp_rate_lut);
1144              dp_rate_idx++) {
1145                 if (!(valid_rates & BIT(dp_rate_idx)))
1146                         continue;
1147
1148                 ret = ti_sn_link_training(pdata, dp_rate_idx, &last_err_str);
1149                 if (!ret)
1150                         break;
1151         }
1152         if (ret) {
1153                 DRM_DEV_ERROR(pdata->dev, "%s (%d)\n", last_err_str, ret);
1154                 return;
1155         }
1156
1157         /* config video parameters */
1158         ti_sn_bridge_set_video_timings(pdata);
1159
1160         /* enable video stream */
1161         regmap_update_bits(pdata->regmap, SN_ENH_FRAME_REG, VSTREAM_ENABLE,
1162                            VSTREAM_ENABLE);
1163 }
1164
1165 static void ti_sn_bridge_atomic_pre_enable(struct drm_bridge *bridge,
1166                                            struct drm_bridge_state *old_bridge_state)
1167 {
1168         struct ti_sn65dsi86 *pdata = bridge_to_ti_sn65dsi86(bridge);
1169
1170         pm_runtime_get_sync(pdata->dev);
1171
1172         if (!pdata->refclk)
1173                 ti_sn65dsi86_enable_comms(pdata);
1174
1175         /* td7: min 100 us after enable before DSI data */
1176         usleep_range(100, 110);
1177 }
1178
1179 static void ti_sn_bridge_atomic_post_disable(struct drm_bridge *bridge,
1180                                              struct drm_bridge_state *old_bridge_state)
1181 {
1182         struct ti_sn65dsi86 *pdata = bridge_to_ti_sn65dsi86(bridge);
1183
1184         /* semi auto link training mode OFF */
1185         regmap_write(pdata->regmap, SN_ML_TX_MODE_REG, 0);
1186         /* Num lanes to 0 as per power sequencing in data sheet */
1187         regmap_update_bits(pdata->regmap, SN_SSC_CONFIG_REG, DP_NUM_LANES_MASK, 0);
1188         /* disable DP PLL */
1189         regmap_write(pdata->regmap, SN_PLL_ENABLE_REG, 0);
1190
1191         if (!pdata->refclk)
1192                 ti_sn65dsi86_disable_comms(pdata);
1193
1194         pm_runtime_put_sync(pdata->dev);
1195 }
1196
1197 static enum drm_connector_status ti_sn_bridge_detect(struct drm_bridge *bridge)
1198 {
1199         struct ti_sn65dsi86 *pdata = bridge_to_ti_sn65dsi86(bridge);
1200         int val = 0;
1201
1202         pm_runtime_get_sync(pdata->dev);
1203         regmap_read(pdata->regmap, SN_HPD_DISABLE_REG, &val);
1204         pm_runtime_put_autosuspend(pdata->dev);
1205
1206         return val & HPD_DEBOUNCED_STATE ? connector_status_connected
1207                                          : connector_status_disconnected;
1208 }
1209
1210 static struct edid *ti_sn_bridge_get_edid(struct drm_bridge *bridge,
1211                                           struct drm_connector *connector)
1212 {
1213         struct ti_sn65dsi86 *pdata = bridge_to_ti_sn65dsi86(bridge);
1214
1215         return drm_get_edid(connector, &pdata->aux.ddc);
1216 }
1217
1218 static const struct drm_bridge_funcs ti_sn_bridge_funcs = {
1219         .attach = ti_sn_bridge_attach,
1220         .detach = ti_sn_bridge_detach,
1221         .mode_valid = ti_sn_bridge_mode_valid,
1222         .get_edid = ti_sn_bridge_get_edid,
1223         .detect = ti_sn_bridge_detect,
1224         .atomic_pre_enable = ti_sn_bridge_atomic_pre_enable,
1225         .atomic_enable = ti_sn_bridge_atomic_enable,
1226         .atomic_disable = ti_sn_bridge_atomic_disable,
1227         .atomic_post_disable = ti_sn_bridge_atomic_post_disable,
1228         .atomic_reset = drm_atomic_helper_bridge_reset,
1229         .atomic_duplicate_state = drm_atomic_helper_bridge_duplicate_state,
1230         .atomic_destroy_state = drm_atomic_helper_bridge_destroy_state,
1231 };
1232
1233 static void ti_sn_bridge_parse_lanes(struct ti_sn65dsi86 *pdata,
1234                                      struct device_node *np)
1235 {
1236         u32 lane_assignments[SN_MAX_DP_LANES] = { 0, 1, 2, 3 };
1237         u32 lane_polarities[SN_MAX_DP_LANES] = { };
1238         struct device_node *endpoint;
1239         u8 ln_assign = 0;
1240         u8 ln_polrs = 0;
1241         int dp_lanes;
1242         int i;
1243
1244         /*
1245          * Read config from the device tree about lane remapping and lane
1246          * polarities.  These are optional and we assume identity map and
1247          * normal polarity if nothing is specified.  It's OK to specify just
1248          * data-lanes but not lane-polarities but not vice versa.
1249          *
1250          * Error checking is light (we just make sure we don't crash or
1251          * buffer overrun) and we assume dts is well formed and specifying
1252          * mappings that the hardware supports.
1253          */
1254         endpoint = of_graph_get_endpoint_by_regs(np, 1, -1);
1255         dp_lanes = drm_of_get_data_lanes_count(endpoint, 1, SN_MAX_DP_LANES);
1256         if (dp_lanes > 0) {
1257                 of_property_read_u32_array(endpoint, "data-lanes",
1258                                            lane_assignments, dp_lanes);
1259                 of_property_read_u32_array(endpoint, "lane-polarities",
1260                                            lane_polarities, dp_lanes);
1261         } else {
1262                 dp_lanes = SN_MAX_DP_LANES;
1263         }
1264         of_node_put(endpoint);
1265
1266         /*
1267          * Convert into register format.  Loop over all lanes even if
1268          * data-lanes had fewer elements so that we nicely initialize
1269          * the LN_ASSIGN register.
1270          */
1271         for (i = SN_MAX_DP_LANES - 1; i >= 0; i--) {
1272                 ln_assign = ln_assign << LN_ASSIGN_WIDTH | lane_assignments[i];
1273                 ln_polrs = ln_polrs << 1 | lane_polarities[i];
1274         }
1275
1276         /* Stash in our struct for when we power on */
1277         pdata->dp_lanes = dp_lanes;
1278         pdata->ln_assign = ln_assign;
1279         pdata->ln_polrs = ln_polrs;
1280 }
1281
1282 static int ti_sn_bridge_parse_dsi_host(struct ti_sn65dsi86 *pdata)
1283 {
1284         struct device_node *np = pdata->dev->of_node;
1285
1286         pdata->host_node = of_graph_get_remote_node(np, 0, 0);
1287
1288         if (!pdata->host_node) {
1289                 DRM_ERROR("remote dsi host node not found\n");
1290                 return -ENODEV;
1291         }
1292
1293         return 0;
1294 }
1295
1296 static int ti_sn_bridge_probe(struct auxiliary_device *adev,
1297                               const struct auxiliary_device_id *id)
1298 {
1299         struct ti_sn65dsi86 *pdata = dev_get_drvdata(adev->dev.parent);
1300         struct device_node *np = pdata->dev->of_node;
1301         int ret;
1302
1303         pdata->next_bridge = devm_drm_of_get_bridge(&adev->dev, np, 1, 0);
1304         if (IS_ERR(pdata->next_bridge))
1305                 return dev_err_probe(&adev->dev, PTR_ERR(pdata->next_bridge),
1306                                      "failed to create panel bridge\n");
1307
1308         ti_sn_bridge_parse_lanes(pdata, np);
1309
1310         ret = ti_sn_bridge_parse_dsi_host(pdata);
1311         if (ret)
1312                 return ret;
1313
1314         pdata->bridge.funcs = &ti_sn_bridge_funcs;
1315         pdata->bridge.of_node = np;
1316         pdata->bridge.type = pdata->next_bridge->type == DRM_MODE_CONNECTOR_DisplayPort
1317                            ? DRM_MODE_CONNECTOR_DisplayPort : DRM_MODE_CONNECTOR_eDP;
1318
1319         if (pdata->bridge.type == DRM_MODE_CONNECTOR_DisplayPort)
1320                 pdata->bridge.ops = DRM_BRIDGE_OP_EDID | DRM_BRIDGE_OP_DETECT;
1321
1322         drm_bridge_add(&pdata->bridge);
1323
1324         ret = ti_sn_attach_host(adev, pdata);
1325         if (ret) {
1326                 dev_err_probe(&adev->dev, ret, "failed to attach dsi host\n");
1327                 goto err_remove_bridge;
1328         }
1329
1330         return 0;
1331
1332 err_remove_bridge:
1333         drm_bridge_remove(&pdata->bridge);
1334         return ret;
1335 }
1336
1337 static void ti_sn_bridge_remove(struct auxiliary_device *adev)
1338 {
1339         struct ti_sn65dsi86 *pdata = dev_get_drvdata(adev->dev.parent);
1340
1341         if (!pdata)
1342                 return;
1343
1344         drm_bridge_remove(&pdata->bridge);
1345
1346         of_node_put(pdata->host_node);
1347 }
1348
1349 static const struct auxiliary_device_id ti_sn_bridge_id_table[] = {
1350         { .name = "ti_sn65dsi86.bridge", },
1351         {},
1352 };
1353
1354 static struct auxiliary_driver ti_sn_bridge_driver = {
1355         .name = "bridge",
1356         .probe = ti_sn_bridge_probe,
1357         .remove = ti_sn_bridge_remove,
1358         .id_table = ti_sn_bridge_id_table,
1359 };
1360
1361 /* -----------------------------------------------------------------------------
1362  * PWM Controller
1363  */
1364 #if defined(CONFIG_PWM)
1365 static int ti_sn_pwm_pin_request(struct ti_sn65dsi86 *pdata)
1366 {
1367         return atomic_xchg(&pdata->pwm_pin_busy, 1) ? -EBUSY : 0;
1368 }
1369
1370 static void ti_sn_pwm_pin_release(struct ti_sn65dsi86 *pdata)
1371 {
1372         atomic_set(&pdata->pwm_pin_busy, 0);
1373 }
1374
1375 static struct ti_sn65dsi86 *pwm_chip_to_ti_sn_bridge(struct pwm_chip *chip)
1376 {
1377         return container_of(chip, struct ti_sn65dsi86, pchip);
1378 }
1379
1380 static int ti_sn_pwm_request(struct pwm_chip *chip, struct pwm_device *pwm)
1381 {
1382         struct ti_sn65dsi86 *pdata = pwm_chip_to_ti_sn_bridge(chip);
1383
1384         return ti_sn_pwm_pin_request(pdata);
1385 }
1386
1387 static void ti_sn_pwm_free(struct pwm_chip *chip, struct pwm_device *pwm)
1388 {
1389         struct ti_sn65dsi86 *pdata = pwm_chip_to_ti_sn_bridge(chip);
1390
1391         ti_sn_pwm_pin_release(pdata);
1392 }
1393
1394 /*
1395  * Limitations:
1396  * - The PWM signal is not driven when the chip is powered down, or in its
1397  *   reset state and the driver does not implement the "suspend state"
1398  *   described in the documentation. In order to save power, state->enabled is
1399  *   interpreted as denoting if the signal is expected to be valid, and is used
1400  *   to determine if the chip needs to be kept powered.
1401  * - Changing both period and duty_cycle is not done atomically, neither is the
1402  *   multi-byte register updates, so the output might briefly be undefined
1403  *   during update.
1404  */
1405 static int ti_sn_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm,
1406                            const struct pwm_state *state)
1407 {
1408         struct ti_sn65dsi86 *pdata = pwm_chip_to_ti_sn_bridge(chip);
1409         unsigned int pwm_en_inv;
1410         unsigned int backlight;
1411         unsigned int pre_div;
1412         unsigned int scale;
1413         u64 period_max;
1414         u64 period;
1415         int ret;
1416
1417         if (!pdata->pwm_enabled) {
1418                 ret = pm_runtime_resume_and_get(chip->dev);
1419                 if (ret < 0)
1420                         return ret;
1421         }
1422
1423         if (state->enabled) {
1424                 if (!pdata->pwm_enabled) {
1425                         /*
1426                          * The chip might have been powered down while we
1427                          * didn't hold a PM runtime reference, so mux in the
1428                          * PWM function on the GPIO pin again.
1429                          */
1430                         ret = regmap_update_bits(pdata->regmap, SN_GPIO_CTRL_REG,
1431                                                  SN_GPIO_MUX_MASK << (2 * SN_PWM_GPIO_IDX),
1432                                                  SN_GPIO_MUX_SPECIAL << (2 * SN_PWM_GPIO_IDX));
1433                         if (ret) {
1434                                 dev_err(chip->dev, "failed to mux in PWM function\n");
1435                                 goto out;
1436                         }
1437                 }
1438
1439                 /*
1440                  * Per the datasheet the PWM frequency is given by:
1441                  *
1442                  *                          REFCLK_FREQ
1443                  *   PWM_FREQ = -----------------------------------
1444                  *               PWM_PRE_DIV * BACKLIGHT_SCALE + 1
1445                  *
1446                  * However, after careful review the author is convinced that
1447                  * the documentation has lost some parenthesis around
1448                  * "BACKLIGHT_SCALE + 1".
1449                  *
1450                  * With the period T_pwm = 1/PWM_FREQ this can be written:
1451                  *
1452                  *   T_pwm * REFCLK_FREQ = PWM_PRE_DIV * (BACKLIGHT_SCALE + 1)
1453                  *
1454                  * In order to keep BACKLIGHT_SCALE within its 16 bits,
1455                  * PWM_PRE_DIV must be:
1456                  *
1457                  *                     T_pwm * REFCLK_FREQ
1458                  *   PWM_PRE_DIV >= -------------------------
1459                  *                   BACKLIGHT_SCALE_MAX + 1
1460                  *
1461                  * To simplify the search and to favour higher resolution of
1462                  * the duty cycle over accuracy of the period, the lowest
1463                  * possible PWM_PRE_DIV is used. Finally the scale is
1464                  * calculated as:
1465                  *
1466                  *                      T_pwm * REFCLK_FREQ
1467                  *   BACKLIGHT_SCALE = ---------------------- - 1
1468                  *                          PWM_PRE_DIV
1469                  *
1470                  * Here T_pwm is represented in seconds, so appropriate scaling
1471                  * to nanoseconds is necessary.
1472                  */
1473
1474                 /* Minimum T_pwm is 1 / REFCLK_FREQ */
1475                 if (state->period <= NSEC_PER_SEC / pdata->pwm_refclk_freq) {
1476                         ret = -EINVAL;
1477                         goto out;
1478                 }
1479
1480                 /*
1481                  * Maximum T_pwm is 255 * (65535 + 1) / REFCLK_FREQ
1482                  * Limit period to this to avoid overflows
1483                  */
1484                 period_max = div_u64((u64)NSEC_PER_SEC * 255 * (65535 + 1),
1485                                      pdata->pwm_refclk_freq);
1486                 period = min(state->period, period_max);
1487
1488                 pre_div = DIV64_U64_ROUND_UP(period * pdata->pwm_refclk_freq,
1489                                              (u64)NSEC_PER_SEC * (BACKLIGHT_SCALE_MAX + 1));
1490                 scale = div64_u64(period * pdata->pwm_refclk_freq, (u64)NSEC_PER_SEC * pre_div) - 1;
1491
1492                 /*
1493                  * The documentation has the duty ratio given as:
1494                  *
1495                  *     duty          BACKLIGHT
1496                  *   ------- = ---------------------
1497                  *    period    BACKLIGHT_SCALE + 1
1498                  *
1499                  * Solve for BACKLIGHT, substituting BACKLIGHT_SCALE according
1500                  * to definition above and adjusting for nanosecond
1501                  * representation of duty cycle gives us:
1502                  */
1503                 backlight = div64_u64(state->duty_cycle * pdata->pwm_refclk_freq,
1504                                       (u64)NSEC_PER_SEC * pre_div);
1505                 if (backlight > scale)
1506                         backlight = scale;
1507
1508                 ret = regmap_write(pdata->regmap, SN_PWM_PRE_DIV_REG, pre_div);
1509                 if (ret) {
1510                         dev_err(chip->dev, "failed to update PWM_PRE_DIV\n");
1511                         goto out;
1512                 }
1513
1514                 ti_sn65dsi86_write_u16(pdata, SN_BACKLIGHT_SCALE_REG, scale);
1515                 ti_sn65dsi86_write_u16(pdata, SN_BACKLIGHT_REG, backlight);
1516         }
1517
1518         pwm_en_inv = FIELD_PREP(SN_PWM_EN_MASK, state->enabled) |
1519                      FIELD_PREP(SN_PWM_INV_MASK, state->polarity == PWM_POLARITY_INVERSED);
1520         ret = regmap_write(pdata->regmap, SN_PWM_EN_INV_REG, pwm_en_inv);
1521         if (ret) {
1522                 dev_err(chip->dev, "failed to update PWM_EN/PWM_INV\n");
1523                 goto out;
1524         }
1525
1526         pdata->pwm_enabled = state->enabled;
1527 out:
1528
1529         if (!pdata->pwm_enabled)
1530                 pm_runtime_put_sync(chip->dev);
1531
1532         return ret;
1533 }
1534
1535 static int ti_sn_pwm_get_state(struct pwm_chip *chip, struct pwm_device *pwm,
1536                                struct pwm_state *state)
1537 {
1538         struct ti_sn65dsi86 *pdata = pwm_chip_to_ti_sn_bridge(chip);
1539         unsigned int pwm_en_inv;
1540         unsigned int pre_div;
1541         u16 backlight;
1542         u16 scale;
1543         int ret;
1544
1545         ret = regmap_read(pdata->regmap, SN_PWM_EN_INV_REG, &pwm_en_inv);
1546         if (ret)
1547                 return ret;
1548
1549         ret = ti_sn65dsi86_read_u16(pdata, SN_BACKLIGHT_SCALE_REG, &scale);
1550         if (ret)
1551                 return ret;
1552
1553         ret = ti_sn65dsi86_read_u16(pdata, SN_BACKLIGHT_REG, &backlight);
1554         if (ret)
1555                 return ret;
1556
1557         ret = regmap_read(pdata->regmap, SN_PWM_PRE_DIV_REG, &pre_div);
1558         if (ret)
1559                 return ret;
1560
1561         state->enabled = FIELD_GET(SN_PWM_EN_MASK, pwm_en_inv);
1562         if (FIELD_GET(SN_PWM_INV_MASK, pwm_en_inv))
1563                 state->polarity = PWM_POLARITY_INVERSED;
1564         else
1565                 state->polarity = PWM_POLARITY_NORMAL;
1566
1567         state->period = DIV_ROUND_UP_ULL((u64)NSEC_PER_SEC * pre_div * (scale + 1),
1568                                          pdata->pwm_refclk_freq);
1569         state->duty_cycle = DIV_ROUND_UP_ULL((u64)NSEC_PER_SEC * pre_div * backlight,
1570                                              pdata->pwm_refclk_freq);
1571
1572         if (state->duty_cycle > state->period)
1573                 state->duty_cycle = state->period;
1574
1575         return 0;
1576 }
1577
1578 static const struct pwm_ops ti_sn_pwm_ops = {
1579         .request = ti_sn_pwm_request,
1580         .free = ti_sn_pwm_free,
1581         .apply = ti_sn_pwm_apply,
1582         .get_state = ti_sn_pwm_get_state,
1583 };
1584
1585 static int ti_sn_pwm_probe(struct auxiliary_device *adev,
1586                            const struct auxiliary_device_id *id)
1587 {
1588         struct ti_sn65dsi86 *pdata = dev_get_drvdata(adev->dev.parent);
1589
1590         pdata->pchip.dev = &adev->dev;
1591         pdata->pchip.ops = &ti_sn_pwm_ops;
1592         pdata->pchip.npwm = 1;
1593         pdata->pchip.of_xlate = of_pwm_single_xlate;
1594         pdata->pchip.of_pwm_n_cells = 1;
1595
1596         devm_pm_runtime_enable(&adev->dev);
1597
1598         return pwmchip_add(&pdata->pchip);
1599 }
1600
1601 static void ti_sn_pwm_remove(struct auxiliary_device *adev)
1602 {
1603         struct ti_sn65dsi86 *pdata = dev_get_drvdata(adev->dev.parent);
1604
1605         pwmchip_remove(&pdata->pchip);
1606
1607         if (pdata->pwm_enabled)
1608                 pm_runtime_put_sync(&adev->dev);
1609 }
1610
1611 static const struct auxiliary_device_id ti_sn_pwm_id_table[] = {
1612         { .name = "ti_sn65dsi86.pwm", },
1613         {},
1614 };
1615
1616 static struct auxiliary_driver ti_sn_pwm_driver = {
1617         .name = "pwm",
1618         .probe = ti_sn_pwm_probe,
1619         .remove = ti_sn_pwm_remove,
1620         .id_table = ti_sn_pwm_id_table,
1621 };
1622
1623 static int __init ti_sn_pwm_register(void)
1624 {
1625         return auxiliary_driver_register(&ti_sn_pwm_driver);
1626 }
1627
1628 static void ti_sn_pwm_unregister(void)
1629 {
1630         auxiliary_driver_unregister(&ti_sn_pwm_driver);
1631 }
1632
1633 #else
1634 static inline int ti_sn_pwm_pin_request(struct ti_sn65dsi86 *pdata) { return 0; }
1635 static inline void ti_sn_pwm_pin_release(struct ti_sn65dsi86 *pdata) {}
1636
1637 static inline int ti_sn_pwm_register(void) { return 0; }
1638 static inline void ti_sn_pwm_unregister(void) {}
1639 #endif
1640
1641 /* -----------------------------------------------------------------------------
1642  * GPIO Controller
1643  */
1644 #if defined(CONFIG_OF_GPIO)
1645
1646 static int tn_sn_bridge_of_xlate(struct gpio_chip *chip,
1647                                  const struct of_phandle_args *gpiospec,
1648                                  u32 *flags)
1649 {
1650         if (WARN_ON(gpiospec->args_count < chip->of_gpio_n_cells))
1651                 return -EINVAL;
1652
1653         if (gpiospec->args[0] > chip->ngpio || gpiospec->args[0] < 1)
1654                 return -EINVAL;
1655
1656         if (flags)
1657                 *flags = gpiospec->args[1];
1658
1659         return gpiospec->args[0] - SN_GPIO_PHYSICAL_OFFSET;
1660 }
1661
1662 static int ti_sn_bridge_gpio_get_direction(struct gpio_chip *chip,
1663                                            unsigned int offset)
1664 {
1665         struct ti_sn65dsi86 *pdata = gpiochip_get_data(chip);
1666
1667         /*
1668          * We already have to keep track of the direction because we use
1669          * that to figure out whether we've powered the device.  We can
1670          * just return that rather than (maybe) powering up the device
1671          * to ask its direction.
1672          */
1673         return test_bit(offset, pdata->gchip_output) ?
1674                 GPIO_LINE_DIRECTION_OUT : GPIO_LINE_DIRECTION_IN;
1675 }
1676
1677 static int ti_sn_bridge_gpio_get(struct gpio_chip *chip, unsigned int offset)
1678 {
1679         struct ti_sn65dsi86 *pdata = gpiochip_get_data(chip);
1680         unsigned int val;
1681         int ret;
1682
1683         /*
1684          * When the pin is an input we don't forcibly keep the bridge
1685          * powered--we just power it on to read the pin.  NOTE: part of
1686          * the reason this works is that the bridge defaults (when
1687          * powered back on) to all 4 GPIOs being configured as GPIO input.
1688          * Also note that if something else is keeping the chip powered the
1689          * pm_runtime functions are lightweight increments of a refcount.
1690          */
1691         pm_runtime_get_sync(pdata->dev);
1692         ret = regmap_read(pdata->regmap, SN_GPIO_IO_REG, &val);
1693         pm_runtime_put_autosuspend(pdata->dev);
1694
1695         if (ret)
1696                 return ret;
1697
1698         return !!(val & BIT(SN_GPIO_INPUT_SHIFT + offset));
1699 }
1700
1701 static void ti_sn_bridge_gpio_set(struct gpio_chip *chip, unsigned int offset,
1702                                   int val)
1703 {
1704         struct ti_sn65dsi86 *pdata = gpiochip_get_data(chip);
1705         int ret;
1706
1707         if (!test_bit(offset, pdata->gchip_output)) {
1708                 dev_err(pdata->dev, "Ignoring GPIO set while input\n");
1709                 return;
1710         }
1711
1712         val &= 1;
1713         ret = regmap_update_bits(pdata->regmap, SN_GPIO_IO_REG,
1714                                  BIT(SN_GPIO_OUTPUT_SHIFT + offset),
1715                                  val << (SN_GPIO_OUTPUT_SHIFT + offset));
1716         if (ret)
1717                 dev_warn(pdata->dev,
1718                          "Failed to set bridge GPIO %u: %d\n", offset, ret);
1719 }
1720
1721 static int ti_sn_bridge_gpio_direction_input(struct gpio_chip *chip,
1722                                              unsigned int offset)
1723 {
1724         struct ti_sn65dsi86 *pdata = gpiochip_get_data(chip);
1725         int shift = offset * 2;
1726         int ret;
1727
1728         if (!test_and_clear_bit(offset, pdata->gchip_output))
1729                 return 0;
1730
1731         ret = regmap_update_bits(pdata->regmap, SN_GPIO_CTRL_REG,
1732                                  SN_GPIO_MUX_MASK << shift,
1733                                  SN_GPIO_MUX_INPUT << shift);
1734         if (ret) {
1735                 set_bit(offset, pdata->gchip_output);
1736                 return ret;
1737         }
1738
1739         /*
1740          * NOTE: if nobody else is powering the device this may fully power
1741          * it off and when it comes back it will have lost all state, but
1742          * that's OK because the default is input and we're now an input.
1743          */
1744         pm_runtime_put_autosuspend(pdata->dev);
1745
1746         return 0;
1747 }
1748
1749 static int ti_sn_bridge_gpio_direction_output(struct gpio_chip *chip,
1750                                               unsigned int offset, int val)
1751 {
1752         struct ti_sn65dsi86 *pdata = gpiochip_get_data(chip);
1753         int shift = offset * 2;
1754         int ret;
1755
1756         if (test_and_set_bit(offset, pdata->gchip_output))
1757                 return 0;
1758
1759         pm_runtime_get_sync(pdata->dev);
1760
1761         /* Set value first to avoid glitching */
1762         ti_sn_bridge_gpio_set(chip, offset, val);
1763
1764         /* Set direction */
1765         ret = regmap_update_bits(pdata->regmap, SN_GPIO_CTRL_REG,
1766                                  SN_GPIO_MUX_MASK << shift,
1767                                  SN_GPIO_MUX_OUTPUT << shift);
1768         if (ret) {
1769                 clear_bit(offset, pdata->gchip_output);
1770                 pm_runtime_put_autosuspend(pdata->dev);
1771         }
1772
1773         return ret;
1774 }
1775
1776 static int ti_sn_bridge_gpio_request(struct gpio_chip *chip, unsigned int offset)
1777 {
1778         struct ti_sn65dsi86 *pdata = gpiochip_get_data(chip);
1779
1780         if (offset == SN_PWM_GPIO_IDX)
1781                 return ti_sn_pwm_pin_request(pdata);
1782
1783         return 0;
1784 }
1785
1786 static void ti_sn_bridge_gpio_free(struct gpio_chip *chip, unsigned int offset)
1787 {
1788         struct ti_sn65dsi86 *pdata = gpiochip_get_data(chip);
1789
1790         /* We won't keep pm_runtime if we're input, so switch there on free */
1791         ti_sn_bridge_gpio_direction_input(chip, offset);
1792
1793         if (offset == SN_PWM_GPIO_IDX)
1794                 ti_sn_pwm_pin_release(pdata);
1795 }
1796
1797 static const char * const ti_sn_bridge_gpio_names[SN_NUM_GPIOS] = {
1798         "GPIO1", "GPIO2", "GPIO3", "GPIO4"
1799 };
1800
1801 static int ti_sn_gpio_probe(struct auxiliary_device *adev,
1802                             const struct auxiliary_device_id *id)
1803 {
1804         struct ti_sn65dsi86 *pdata = dev_get_drvdata(adev->dev.parent);
1805         int ret;
1806
1807         /* Only init if someone is going to use us as a GPIO controller */
1808         if (!of_property_read_bool(pdata->dev->of_node, "gpio-controller"))
1809                 return 0;
1810
1811         pdata->gchip.label = dev_name(pdata->dev);
1812         pdata->gchip.parent = pdata->dev;
1813         pdata->gchip.owner = THIS_MODULE;
1814         pdata->gchip.of_xlate = tn_sn_bridge_of_xlate;
1815         pdata->gchip.of_gpio_n_cells = 2;
1816         pdata->gchip.request = ti_sn_bridge_gpio_request;
1817         pdata->gchip.free = ti_sn_bridge_gpio_free;
1818         pdata->gchip.get_direction = ti_sn_bridge_gpio_get_direction;
1819         pdata->gchip.direction_input = ti_sn_bridge_gpio_direction_input;
1820         pdata->gchip.direction_output = ti_sn_bridge_gpio_direction_output;
1821         pdata->gchip.get = ti_sn_bridge_gpio_get;
1822         pdata->gchip.set = ti_sn_bridge_gpio_set;
1823         pdata->gchip.can_sleep = true;
1824         pdata->gchip.names = ti_sn_bridge_gpio_names;
1825         pdata->gchip.ngpio = SN_NUM_GPIOS;
1826         pdata->gchip.base = -1;
1827         ret = devm_gpiochip_add_data(&adev->dev, &pdata->gchip, pdata);
1828         if (ret)
1829                 dev_err(pdata->dev, "can't add gpio chip\n");
1830
1831         return ret;
1832 }
1833
1834 static const struct auxiliary_device_id ti_sn_gpio_id_table[] = {
1835         { .name = "ti_sn65dsi86.gpio", },
1836         {},
1837 };
1838
1839 MODULE_DEVICE_TABLE(auxiliary, ti_sn_gpio_id_table);
1840
1841 static struct auxiliary_driver ti_sn_gpio_driver = {
1842         .name = "gpio",
1843         .probe = ti_sn_gpio_probe,
1844         .id_table = ti_sn_gpio_id_table,
1845 };
1846
1847 static int __init ti_sn_gpio_register(void)
1848 {
1849         return auxiliary_driver_register(&ti_sn_gpio_driver);
1850 }
1851
1852 static void ti_sn_gpio_unregister(void)
1853 {
1854         auxiliary_driver_unregister(&ti_sn_gpio_driver);
1855 }
1856
1857 #else
1858
1859 static inline int ti_sn_gpio_register(void) { return 0; }
1860 static inline void ti_sn_gpio_unregister(void) {}
1861
1862 #endif
1863
1864 /* -----------------------------------------------------------------------------
1865  * Probe & Remove
1866  */
1867
1868 static void ti_sn65dsi86_runtime_disable(void *data)
1869 {
1870         pm_runtime_dont_use_autosuspend(data);
1871         pm_runtime_disable(data);
1872 }
1873
1874 static int ti_sn65dsi86_parse_regulators(struct ti_sn65dsi86 *pdata)
1875 {
1876         unsigned int i;
1877         const char * const ti_sn_bridge_supply_names[] = {
1878                 "vcca", "vcc", "vccio", "vpll",
1879         };
1880
1881         for (i = 0; i < SN_REGULATOR_SUPPLY_NUM; i++)
1882                 pdata->supplies[i].supply = ti_sn_bridge_supply_names[i];
1883
1884         return devm_regulator_bulk_get(pdata->dev, SN_REGULATOR_SUPPLY_NUM,
1885                                        pdata->supplies);
1886 }
1887
1888 static int ti_sn65dsi86_probe(struct i2c_client *client)
1889 {
1890         struct device *dev = &client->dev;
1891         struct ti_sn65dsi86 *pdata;
1892         int ret;
1893
1894         if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
1895                 DRM_ERROR("device doesn't support I2C\n");
1896                 return -ENODEV;
1897         }
1898
1899         pdata = devm_kzalloc(dev, sizeof(struct ti_sn65dsi86), GFP_KERNEL);
1900         if (!pdata)
1901                 return -ENOMEM;
1902         dev_set_drvdata(dev, pdata);
1903         pdata->dev = dev;
1904
1905         mutex_init(&pdata->comms_mutex);
1906
1907         pdata->regmap = devm_regmap_init_i2c(client,
1908                                              &ti_sn65dsi86_regmap_config);
1909         if (IS_ERR(pdata->regmap))
1910                 return dev_err_probe(dev, PTR_ERR(pdata->regmap),
1911                                      "regmap i2c init failed\n");
1912
1913         pdata->enable_gpio = devm_gpiod_get_optional(dev, "enable",
1914                                                      GPIOD_OUT_LOW);
1915         if (IS_ERR(pdata->enable_gpio))
1916                 return dev_err_probe(dev, PTR_ERR(pdata->enable_gpio),
1917                                      "failed to get enable gpio from DT\n");
1918
1919         ret = ti_sn65dsi86_parse_regulators(pdata);
1920         if (ret)
1921                 return dev_err_probe(dev, ret, "failed to parse regulators\n");
1922
1923         pdata->refclk = devm_clk_get_optional(dev, "refclk");
1924         if (IS_ERR(pdata->refclk))
1925                 return dev_err_probe(dev, PTR_ERR(pdata->refclk),
1926                                      "failed to get reference clock\n");
1927
1928         pm_runtime_enable(dev);
1929         pm_runtime_set_autosuspend_delay(pdata->dev, 500);
1930         pm_runtime_use_autosuspend(pdata->dev);
1931         ret = devm_add_action_or_reset(dev, ti_sn65dsi86_runtime_disable, dev);
1932         if (ret)
1933                 return ret;
1934
1935         ti_sn65dsi86_debugfs_init(pdata);
1936
1937         /*
1938          * Break ourselves up into a collection of aux devices. The only real
1939          * motiviation here is to solve the chicken-and-egg problem of probe
1940          * ordering. The bridge wants the panel to be there when it probes.
1941          * The panel wants its HPD GPIO (provided by sn65dsi86 on some boards)
1942          * when it probes. The panel and maybe backlight might want the DDC
1943          * bus or the pwm_chip. Having sub-devices allows the some sub devices
1944          * to finish probing even if others return -EPROBE_DEFER and gets us
1945          * around the problems.
1946          */
1947
1948         if (IS_ENABLED(CONFIG_OF_GPIO)) {
1949                 ret = ti_sn65dsi86_add_aux_device(pdata, &pdata->gpio_aux, "gpio");
1950                 if (ret)
1951                         return ret;
1952         }
1953
1954         if (IS_ENABLED(CONFIG_PWM)) {
1955                 ret = ti_sn65dsi86_add_aux_device(pdata, &pdata->pwm_aux, "pwm");
1956                 if (ret)
1957                         return ret;
1958         }
1959
1960         /*
1961          * NOTE: At the end of the AUX channel probe we'll add the aux device
1962          * for the bridge. This is because the bridge can't be used until the
1963          * AUX channel is there and this is a very simple solution to the
1964          * dependency problem.
1965          */
1966         return ti_sn65dsi86_add_aux_device(pdata, &pdata->aux_aux, "aux");
1967 }
1968
1969 static struct i2c_device_id ti_sn65dsi86_id[] = {
1970         { "ti,sn65dsi86", 0},
1971         {},
1972 };
1973 MODULE_DEVICE_TABLE(i2c, ti_sn65dsi86_id);
1974
1975 static const struct of_device_id ti_sn65dsi86_match_table[] = {
1976         {.compatible = "ti,sn65dsi86"},
1977         {},
1978 };
1979 MODULE_DEVICE_TABLE(of, ti_sn65dsi86_match_table);
1980
1981 static struct i2c_driver ti_sn65dsi86_driver = {
1982         .driver = {
1983                 .name = "ti_sn65dsi86",
1984                 .of_match_table = ti_sn65dsi86_match_table,
1985                 .pm = &ti_sn65dsi86_pm_ops,
1986         },
1987         .probe = ti_sn65dsi86_probe,
1988         .id_table = ti_sn65dsi86_id,
1989 };
1990
1991 static int __init ti_sn65dsi86_init(void)
1992 {
1993         int ret;
1994
1995         ret = i2c_add_driver(&ti_sn65dsi86_driver);
1996         if (ret)
1997                 return ret;
1998
1999         ret = ti_sn_gpio_register();
2000         if (ret)
2001                 goto err_main_was_registered;
2002
2003         ret = ti_sn_pwm_register();
2004         if (ret)
2005                 goto err_gpio_was_registered;
2006
2007         ret = auxiliary_driver_register(&ti_sn_aux_driver);
2008         if (ret)
2009                 goto err_pwm_was_registered;
2010
2011         ret = auxiliary_driver_register(&ti_sn_bridge_driver);
2012         if (ret)
2013                 goto err_aux_was_registered;
2014
2015         return 0;
2016
2017 err_aux_was_registered:
2018         auxiliary_driver_unregister(&ti_sn_aux_driver);
2019 err_pwm_was_registered:
2020         ti_sn_pwm_unregister();
2021 err_gpio_was_registered:
2022         ti_sn_gpio_unregister();
2023 err_main_was_registered:
2024         i2c_del_driver(&ti_sn65dsi86_driver);
2025
2026         return ret;
2027 }
2028 module_init(ti_sn65dsi86_init);
2029
2030 static void __exit ti_sn65dsi86_exit(void)
2031 {
2032         auxiliary_driver_unregister(&ti_sn_bridge_driver);
2033         auxiliary_driver_unregister(&ti_sn_aux_driver);
2034         ti_sn_pwm_unregister();
2035         ti_sn_gpio_unregister();
2036         i2c_del_driver(&ti_sn65dsi86_driver);
2037 }
2038 module_exit(ti_sn65dsi86_exit);
2039
2040 MODULE_AUTHOR("Sandeep Panda <spanda@codeaurora.org>");
2041 MODULE_DESCRIPTION("sn65dsi86 DSI to eDP bridge driver");
2042 MODULE_LICENSE("GPL v2");