drivers/char/ipmi/kcs_bmc_aspeed.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Copyright (c) 2015-2018, Intel Corporation.
   4  */
   5
   6 #define pr_fmt(fmt) "aspeed-kcs-bmc: " fmt
   7
   8 #include <linux/atomic.h>
   9 #include <linux/errno.h>
  10 #include <linux/interrupt.h>
  11 #include <linux/io.h>
  12 #include <linux/irq.h>
  13 #include <linux/mfd/syscon.h>
  14 #include <linux/module.h>
  15 #include <linux/of.h>
  16 #include <linux/of_address.h>
  17 #include <linux/platform_device.h>
  18 #include <linux/poll.h>
  19 #include <linux/regmap.h>
  20 #include <linux/sched.h>
  21 #include <linux/slab.h>
  22 #include <linux/timer.h>
  23
  24 #include "kcs_bmc_device.h"
  25
  26
  27 #define DEVICE_NAME     "ast-kcs-bmc"
  28
  29 #define KCS_CHANNEL_MAX     4
  30
  31 /*
  32  * Field class descriptions
  33  *
  34  * LPCyE        Enable LPC channel y
  35  * IBFIEy       Input Buffer Full IRQ Enable for LPC channel y
  36  * IRQxEy       Assert SerIRQ x for LPC channel y (Deprecated, use IDyIRQX, IRQXEy)
  37  * IDyIRQX      Use the specified 4-bit SerIRQ for LPC channel y
  38  * SELyIRQX     SerIRQ polarity for LPC channel y (low: 0, high: 1)
  39  * IRQXEy       Assert the SerIRQ specified in IDyIRQX for LPC channel y
  40  */
  41
  42 #define LPC_TYIRQX_LOW       0b00
  43 #define LPC_TYIRQX_HIGH      0b01
  44 #define LPC_TYIRQX_RSVD      0b10
  45 #define LPC_TYIRQX_RISING    0b11
  46
  47 #define LPC_HICR0            0x000
  48 #define     LPC_HICR0_LPC3E          BIT(7)
  49 #define     LPC_HICR0_LPC2E          BIT(6)
  50 #define     LPC_HICR0_LPC1E          BIT(5)
  51 #define LPC_HICR2            0x008
  52 #define     LPC_HICR2_IBFIE3         BIT(3)
  53 #define     LPC_HICR2_IBFIE2         BIT(2)
  54 #define     LPC_HICR2_IBFIE1         BIT(1)
  55 #define LPC_HICR4            0x010
  56 #define     LPC_HICR4_LADR12AS       BIT(7)
  57 #define     LPC_HICR4_KCSENBL        BIT(2)
  58 #define LPC_SIRQCR0          0x070
  59 /* IRQ{12,1}E1 are deprecated as of AST2600 A3 but necessary for prior chips */
  60 #define     LPC_SIRQCR0_IRQ12E1      BIT(1)
  61 #define     LPC_SIRQCR0_IRQ1E1       BIT(0)
  62 #define LPC_HICR5            0x080
  63 #define     LPC_HICR5_ID3IRQX_MASK   GENMASK(23, 20)
  64 #define     LPC_HICR5_ID3IRQX_SHIFT  20
  65 #define     LPC_HICR5_ID2IRQX_MASK   GENMASK(19, 16)
  66 #define     LPC_HICR5_ID2IRQX_SHIFT  16
  67 #define     LPC_HICR5_SEL3IRQX       BIT(15)
  68 #define     LPC_HICR5_IRQXE3         BIT(14)
  69 #define     LPC_HICR5_SEL2IRQX       BIT(13)
  70 #define     LPC_HICR5_IRQXE2         BIT(12)
  71 #define LPC_LADR3H           0x014
  72 #define LPC_LADR3L           0x018
  73 #define LPC_LADR12H          0x01C
  74 #define LPC_LADR12L          0x020
  75 #define LPC_IDR1             0x024
  76 #define LPC_IDR2             0x028
  77 #define LPC_IDR3             0x02C
  78 #define LPC_ODR1             0x030
  79 #define LPC_ODR2             0x034
  80 #define LPC_ODR3             0x038
  81 #define LPC_STR1             0x03C
  82 #define LPC_STR2             0x040
  83 #define LPC_STR3             0x044
  84 #define LPC_HICRB            0x100
  85 #define     LPC_HICRB_EN16LADR2      BIT(5)
  86 #define     LPC_HICRB_EN16LADR1      BIT(4)
  87 #define     LPC_HICRB_IBFIE4         BIT(1)
  88 #define     LPC_HICRB_LPC4E          BIT(0)
  89 #define LPC_HICRC            0x104
  90 #define     LPC_HICRC_ID4IRQX_MASK   GENMASK(7, 4)
  91 #define     LPC_HICRC_ID4IRQX_SHIFT  4
  92 #define     LPC_HICRC_TY4IRQX_MASK   GENMASK(3, 2)
  93 #define     LPC_HICRC_TY4IRQX_SHIFT  2
  94 #define     LPC_HICRC_OBF4_AUTO_CLR  BIT(1)
  95 #define     LPC_HICRC_IRQXE4         BIT(0)
  96 #define LPC_LADR4            0x110
  97 #define LPC_IDR4             0x114
  98 #define LPC_ODR4             0x118
  99 #define LPC_STR4             0x11C
 100 #define LPC_LSADR12          0x120
 101 #define     LPC_LSADR12_LSADR2_MASK  GENMASK(31, 16)
 102 #define     LPC_LSADR12_LSADR2_SHIFT 16
 103 #define     LPC_LSADR12_LSADR1_MASK  GENMASK(15, 0)
 104 #define     LPC_LSADR12_LSADR1_SHIFT 0
 105
 106 #define OBE_POLL_PERIOD      (HZ / 2)
 107
 108 enum aspeed_kcs_irq_mode {
 109         aspeed_kcs_irq_none,
 110         aspeed_kcs_irq_serirq,
 111 };
 112
 113 struct aspeed_kcs_bmc {
 114         struct kcs_bmc_device kcs_bmc;
 115
 116         struct regmap *map;
 117
 118         struct {
 119                 enum aspeed_kcs_irq_mode mode;
 120                 int id;
 121         } upstream_irq;
 122
 123         struct {
 124                 spinlock_t lock;
 125                 bool remove;
 126                 struct timer_list timer;
 127         } obe;
 128 };
 129
 130 static inline struct aspeed_kcs_bmc *to_aspeed_kcs_bmc(struct kcs_bmc_device *kcs_bmc)
 131 {
 132         return container_of(kcs_bmc, struct aspeed_kcs_bmc, kcs_bmc);
 133 }
 134
 135 static u8 aspeed_kcs_inb(struct kcs_bmc_device *kcs_bmc, u32 reg)
 136 {
 137         struct aspeed_kcs_bmc *priv = to_aspeed_kcs_bmc(kcs_bmc);
 138         u32 val = 0;
 139         int rc;
 140
 141         rc = regmap_read(priv->map, reg, &val);
 142         WARN(rc != 0, "regmap_read() failed: %d\n", rc);
 143
 144         return rc == 0 ? (u8) val : 0;
 145 }
 146
 147 static void aspeed_kcs_outb(struct kcs_bmc_device *kcs_bmc, u32 reg, u8 data)
 148 {
 149         struct aspeed_kcs_bmc *priv = to_aspeed_kcs_bmc(kcs_bmc);
 150         int rc;
 151
 152         rc = regmap_write(priv->map, reg, data);
 153         WARN(rc != 0, "regmap_write() failed: %d\n", rc);
 154
 155         /* Trigger the upstream IRQ on ODR writes, if enabled */
 156
 157         switch (reg) {
 158         case LPC_ODR1:
 159         case LPC_ODR2:
 160         case LPC_ODR3:
 161         case LPC_ODR4:
 162                 break;
 163         default:
 164                 return;
 165         }
 166
 167         if (priv->upstream_irq.mode != aspeed_kcs_irq_serirq)
 168                 return;
 169
 170         switch (kcs_bmc->channel) {
 171         case 1:
 172                 switch (priv->upstream_irq.id) {
 173                 case 12:
 174                         regmap_update_bits(priv->map, LPC_SIRQCR0, LPC_SIRQCR0_IRQ12E1,
 175                                            LPC_SIRQCR0_IRQ12E1);
 176                         break;
 177                 case 1:
 178                         regmap_update_bits(priv->map, LPC_SIRQCR0, LPC_SIRQCR0_IRQ1E1,
 179                                            LPC_SIRQCR0_IRQ1E1);
 180                         break;
 181                 default:
 182                         break;
 183                 }
 184                 break;
 185         case 2:
 186                 regmap_update_bits(priv->map, LPC_HICR5, LPC_HICR5_IRQXE2, LPC_HICR5_IRQXE2);
 187                 break;
 188         case 3:
 189                 regmap_update_bits(priv->map, LPC_HICR5, LPC_HICR5_IRQXE3, LPC_HICR5_IRQXE3);
 190                 break;
 191         case 4:
 192                 regmap_update_bits(priv->map, LPC_HICRC, LPC_HICRC_IRQXE4, LPC_HICRC_IRQXE4);
 193                 break;
 194         default:
 195                 break;
 196         }
 197 }
 198
 199 static void aspeed_kcs_updateb(struct kcs_bmc_device *kcs_bmc, u32 reg, u8 mask, u8 val)
 200 {
 201         struct aspeed_kcs_bmc *priv = to_aspeed_kcs_bmc(kcs_bmc);
 202         int rc;
 203
 204         rc = regmap_update_bits(priv->map, reg, mask, val);
 205         WARN(rc != 0, "regmap_update_bits() failed: %d\n", rc);
 206 }
 207
 208 /*
 209  * We note D for Data, and C for Cmd/Status, default rules are
 210  *
 211  * 1. Only the D address is given:
 212  *   A. KCS1/KCS2 (D/C: X/X+4)
 213  *      D/C: CA0h/CA4h
 214  *      D/C: CA8h/CACh
 215  *   B. KCS3 (D/C: XX2/XX3h)
 216  *      D/C: CA2h/CA3h
 217  *   C. KCS4 (D/C: X/X+1)
 218  *      D/C: CA4h/CA5h
 219  *
 220  * 2. Both the D/C addresses are given:
 221  *   A. KCS1/KCS2/KCS4 (D/C: X/Y)
 222  *      D/C: CA0h/CA1h
 223  *      D/C: CA8h/CA9h
 224  *      D/C: CA4h/CA5h
 225  *   B. KCS3 (D/C: XX2/XX3h)
 226  *      D/C: CA2h/CA3h
 227  */
 228 static int aspeed_kcs_set_address(struct kcs_bmc_device *kcs_bmc, u32 addrs[2], int nr_addrs)
 229 {
 230         struct aspeed_kcs_bmc *priv = to_aspeed_kcs_bmc(kcs_bmc);
 231
 232         if (WARN_ON(nr_addrs < 1 || nr_addrs > 2))
 233                 return -EINVAL;
 234
 235         switch (priv->kcs_bmc.channel) {
 236         case 1:
 237                 regmap_update_bits(priv->map, LPC_HICR4, LPC_HICR4_LADR12AS, 0);
 238                 regmap_write(priv->map, LPC_LADR12H, addrs[0] >> 8);
 239                 regmap_write(priv->map, LPC_LADR12L, addrs[0] & 0xFF);
 240                 if (nr_addrs == 2) {
 241                         regmap_update_bits(priv->map, LPC_LSADR12, LPC_LSADR12_LSADR1_MASK,
 242                                            addrs[1] << LPC_LSADR12_LSADR1_SHIFT);
 243
 244                         regmap_update_bits(priv->map, LPC_HICRB, LPC_HICRB_EN16LADR1,
 245                                            LPC_HICRB_EN16LADR1);
 246                 }
 247                 break;
 248
 249         case 2:
 250                 regmap_update_bits(priv->map, LPC_HICR4, LPC_HICR4_LADR12AS, LPC_HICR4_LADR12AS);
 251                 regmap_write(priv->map, LPC_LADR12H, addrs[0] >> 8);
 252                 regmap_write(priv->map, LPC_LADR12L, addrs[0] & 0xFF);
 253                 if (nr_addrs == 2) {
 254                         regmap_update_bits(priv->map, LPC_LSADR12, LPC_LSADR12_LSADR2_MASK,
 255                                            addrs[1] << LPC_LSADR12_LSADR2_SHIFT);
 256
 257                         regmap_update_bits(priv->map, LPC_HICRB, LPC_HICRB_EN16LADR2,
 258                                            LPC_HICRB_EN16LADR2);
 259                 }
 260                 break;
 261
 262         case 3:
 263                 if (nr_addrs == 2) {
 264                         dev_err(priv->kcs_bmc.dev,
 265                                 "Channel 3 only supports inferred status IO address\n");
 266                         return -EINVAL;
 267                 }
 268
 269                 regmap_write(priv->map, LPC_LADR3H, addrs[0] >> 8);
 270                 regmap_write(priv->map, LPC_LADR3L, addrs[0] & 0xFF);
 271                 break;
 272
 273         case 4:
 274                 if (nr_addrs == 1)
 275                         regmap_write(priv->map, LPC_LADR4, ((addrs[0] + 1) << 16) | addrs[0]);
 276                 else
 277                         regmap_write(priv->map, LPC_LADR4, (addrs[1] << 16) | addrs[0]);
 278
 279                 break;
 280
 281         default:
 282                 return -EINVAL;
 283         }
 284
 285         return 0;
 286 }
 287
 288 static inline int aspeed_kcs_map_serirq_type(u32 dt_type)
 289 {
 290         switch (dt_type) {
 291         case IRQ_TYPE_EDGE_RISING:
 292                 return LPC_TYIRQX_RISING;
 293         case IRQ_TYPE_LEVEL_HIGH:
 294                 return LPC_TYIRQX_HIGH;
 295         case IRQ_TYPE_LEVEL_LOW:
 296                 return LPC_TYIRQX_LOW;
 297         default:
 298                 return -EINVAL;
 299         }
 300 }
 301
 302 static int aspeed_kcs_config_upstream_irq(struct aspeed_kcs_bmc *priv, u32 id, u32 dt_type)
 303 {
 304         unsigned int mask, val, hw_type;
 305         int ret;
 306
 307         if (id > 15)
 308                 return -EINVAL;
 309
 310         ret = aspeed_kcs_map_serirq_type(dt_type);
 311         if (ret < 0)
 312                 return ret;
 313         hw_type = ret;
 314
 315         priv->upstream_irq.mode = aspeed_kcs_irq_serirq;
 316         priv->upstream_irq.id = id;
 317
 318         switch (priv->kcs_bmc.channel) {
 319         case 1:
 320                 /* Needs IRQxE1 rather than (ID1IRQX, SEL1IRQX, IRQXE1) before AST2600 A3 */
 321                 break;
 322         case 2:
 323                 if (!(hw_type == LPC_TYIRQX_LOW || hw_type == LPC_TYIRQX_HIGH))
 324                         return -EINVAL;
 325
 326                 mask = LPC_HICR5_SEL2IRQX | LPC_HICR5_ID2IRQX_MASK;
 327                 val = (id << LPC_HICR5_ID2IRQX_SHIFT);
 328                 val |= (hw_type == LPC_TYIRQX_HIGH) ? LPC_HICR5_SEL2IRQX : 0;
 329                 regmap_update_bits(priv->map, LPC_HICR5, mask, val);
 330
 331                 break;
 332         case 3:
 333                 if (!(hw_type == LPC_TYIRQX_LOW || hw_type == LPC_TYIRQX_HIGH))
 334                         return -EINVAL;
 335
 336                 mask = LPC_HICR5_SEL3IRQX | LPC_HICR5_ID3IRQX_MASK;
 337                 val = (id << LPC_HICR5_ID3IRQX_SHIFT);
 338                 val |= (hw_type == LPC_TYIRQX_HIGH) ? LPC_HICR5_SEL3IRQX : 0;
 339                 regmap_update_bits(priv->map, LPC_HICR5, mask, val);
 340
 341                 break;
 342         case 4:
 343                 mask = LPC_HICRC_ID4IRQX_MASK | LPC_HICRC_TY4IRQX_MASK | LPC_HICRC_OBF4_AUTO_CLR;
 344                 val = (id << LPC_HICRC_ID4IRQX_SHIFT) | (hw_type << LPC_HICRC_TY4IRQX_SHIFT);
 345                 regmap_update_bits(priv->map, LPC_HICRC, mask, val);
 346                 break;
 347         default:
 348                 dev_warn(priv->kcs_bmc.dev,
 349                          "SerIRQ configuration not supported on KCS channel %d\n",
 350                          priv->kcs_bmc.channel);
 351                 return -EINVAL;
 352         }
 353
 354         return 0;
 355 }
 356
 357 static void aspeed_kcs_enable_channel(struct kcs_bmc_device *kcs_bmc, bool enable)
 358 {
 359         struct aspeed_kcs_bmc *priv = to_aspeed_kcs_bmc(kcs_bmc);
 360
 361         switch (kcs_bmc->channel) {
 362         case 1:
 363                 regmap_update_bits(priv->map, LPC_HICR0, LPC_HICR0_LPC1E, enable * LPC_HICR0_LPC1E);
 364                 return;
 365         case 2:
 366                 regmap_update_bits(priv->map, LPC_HICR0, LPC_HICR0_LPC2E, enable * LPC_HICR0_LPC2E);
 367                 return;
 368         case 3:
 369                 regmap_update_bits(priv->map, LPC_HICR0, LPC_HICR0_LPC3E, enable * LPC_HICR0_LPC3E);
 370                 regmap_update_bits(priv->map, LPC_HICR4,
 371                                    LPC_HICR4_KCSENBL, enable * LPC_HICR4_KCSENBL);
 372                 return;
 373         case 4:
 374                 regmap_update_bits(priv->map, LPC_HICRB, LPC_HICRB_LPC4E, enable * LPC_HICRB_LPC4E);
 375                 return;
 376         default:
 377                 pr_warn("%s: Unsupported channel: %d", __func__, kcs_bmc->channel);
 378                 return;
 379         }
 380 }
 381
 382 static void aspeed_kcs_check_obe(struct timer_list *timer)
 383 {
 384         struct aspeed_kcs_bmc *priv = container_of(timer, struct aspeed_kcs_bmc, obe.timer);
 385         unsigned long flags;
 386         u8 str;
 387
 388         spin_lock_irqsave(&priv->obe.lock, flags);
 389         if (priv->obe.remove) {
 390                 spin_unlock_irqrestore(&priv->obe.lock, flags);
 391                 return;
 392         }
 393
 394         str = aspeed_kcs_inb(&priv->kcs_bmc, priv->kcs_bmc.ioreg.str);
 395         if (str & KCS_BMC_STR_OBF) {
 396                 mod_timer(timer, jiffies + OBE_POLL_PERIOD);
 397                 spin_unlock_irqrestore(&priv->obe.lock, flags);
 398                 return;
 399         }
 400         spin_unlock_irqrestore(&priv->obe.lock, flags);
 401
 402         kcs_bmc_handle_event(&priv->kcs_bmc);
 403 }
 404
 405 static void aspeed_kcs_irq_mask_update(struct kcs_bmc_device *kcs_bmc, u8 mask, u8 state)
 406 {
 407         struct aspeed_kcs_bmc *priv = to_aspeed_kcs_bmc(kcs_bmc);
 408         int rc;
 409         u8 str;
 410
 411         /* We don't have an OBE IRQ, emulate it */
 412         if (mask & KCS_BMC_EVENT_TYPE_OBE) {
 413                 if (KCS_BMC_EVENT_TYPE_OBE & state) {
 414                         /*
 415                          * Given we don't have an OBE IRQ, delay by polling briefly to see if we can
 416                          * observe such an event before returning to the caller. This is not
 417                          * incorrect because OBF may have already become clear before enabling the
 418                          * IRQ if we had one, under which circumstance no event will be propagated
 419                          * anyway.
 420                          *
 421                          * The onus is on the client to perform a race-free check that it hasn't
 422                          * missed the event.
 423                          */
 424                         rc = read_poll_timeout_atomic(aspeed_kcs_inb, str,
 425                                                       !(str & KCS_BMC_STR_OBF), 1, 100, false,
 426                                                       &priv->kcs_bmc, priv->kcs_bmc.ioreg.str);
 427                         /* Time for the slow path? */
 428                         if (rc == -ETIMEDOUT)
 429                                 mod_timer(&priv->obe.timer, jiffies + OBE_POLL_PERIOD);
 430                 } else {
 431                         del_timer(&priv->obe.timer);
 432                 }
 433         }
 434
 435         if (mask & KCS_BMC_EVENT_TYPE_IBF) {
 436                 const bool enable = !!(state & KCS_BMC_EVENT_TYPE_IBF);
 437
 438                 switch (kcs_bmc->channel) {
 439                 case 1:
 440                         regmap_update_bits(priv->map, LPC_HICR2, LPC_HICR2_IBFIE1,
 441                                            enable * LPC_HICR2_IBFIE1);
 442                         return;
 443                 case 2:
 444                         regmap_update_bits(priv->map, LPC_HICR2, LPC_HICR2_IBFIE2,
 445                                            enable * LPC_HICR2_IBFIE2);
 446                         return;
 447                 case 3:
 448                         regmap_update_bits(priv->map, LPC_HICR2, LPC_HICR2_IBFIE3,
 449                                            enable * LPC_HICR2_IBFIE3);
 450                         return;
 451                 case 4:
 452                         regmap_update_bits(priv->map, LPC_HICRB, LPC_HICRB_IBFIE4,
 453                                            enable * LPC_HICRB_IBFIE4);
 454                         return;
 455                 default:
 456                         pr_warn("%s: Unsupported channel: %d", __func__, kcs_bmc->channel);
 457                         return;
 458                 }
 459         }
 460 }
 461
 462 static const struct kcs_bmc_device_ops aspeed_kcs_ops = {
 463         .irq_mask_update = aspeed_kcs_irq_mask_update,
 464         .io_inputb = aspeed_kcs_inb,
 465         .io_outputb = aspeed_kcs_outb,
 466         .io_updateb = aspeed_kcs_updateb,
 467 };
 468
 469 static irqreturn_t aspeed_kcs_irq(int irq, void *arg)
 470 {
 471         struct kcs_bmc_device *kcs_bmc = arg;
 472
 473         return kcs_bmc_handle_event(kcs_bmc);
 474 }
 475
 476 static int aspeed_kcs_config_downstream_irq(struct kcs_bmc_device *kcs_bmc,
 477                         struct platform_device *pdev)
 478 {
 479         struct device *dev = &pdev->dev;
 480         int irq;
 481
 482         irq = platform_get_irq(pdev, 0);
 483         if (irq < 0)
 484                 return irq;
 485
 486         return devm_request_irq(dev, irq, aspeed_kcs_irq, IRQF_SHARED,
 487                                 dev_name(dev), kcs_bmc);
 488 }
 489
 490 static const struct kcs_ioreg ast_kcs_bmc_ioregs[KCS_CHANNEL_MAX] = {
 491         { .idr = LPC_IDR1, .odr = LPC_ODR1, .str = LPC_STR1 },
 492         { .idr = LPC_IDR2, .odr = LPC_ODR2, .str = LPC_STR2 },
 493         { .idr = LPC_IDR3, .odr = LPC_ODR3, .str = LPC_STR3 },
 494         { .idr = LPC_IDR4, .odr = LPC_ODR4, .str = LPC_STR4 },
 495 };
 496
 497 static int aspeed_kcs_of_get_channel(struct platform_device *pdev)
 498 {
 499         struct device_node *np;
 500         struct kcs_ioreg ioreg;
 501         const __be32 *reg;
 502         int i;
 503
 504         np = pdev->dev.of_node;
 505
 506         /* Don't translate addresses, we want offsets for the regmaps */
 507         reg = of_get_address(np, 0, NULL, NULL);
 508         if (!reg)
 509                 return -EINVAL;
 510         ioreg.idr = be32_to_cpup(reg);
 511
 512         reg = of_get_address(np, 1, NULL, NULL);
 513         if (!reg)
 514                 return -EINVAL;
 515         ioreg.odr = be32_to_cpup(reg);
 516
 517         reg = of_get_address(np, 2, NULL, NULL);
 518         if (!reg)
 519                 return -EINVAL;
 520         ioreg.str = be32_to_cpup(reg);
 521
 522         for (i = 0; i < ARRAY_SIZE(ast_kcs_bmc_ioregs); i++) {
 523                 if (!memcmp(&ast_kcs_bmc_ioregs[i], &ioreg, sizeof(ioreg)))
 524                         return i + 1;
 525         }
 526         return -EINVAL;
 527 }
 528
 529 static int
 530 aspeed_kcs_of_get_io_address(struct platform_device *pdev, u32 addrs[2])
 531 {
 532         int rc;
 533
 534         rc = of_property_read_variable_u32_array(pdev->dev.of_node,
 535                                                  "aspeed,lpc-io-reg",
 536                                                  addrs, 1, 2);
 537         if (rc < 0) {
 538                 dev_err(&pdev->dev, "No valid 'aspeed,lpc-io-reg' configured\n");
 539                 return rc;
 540         }
 541
 542         if (addrs[0] > 0xffff) {
 543                 dev_err(&pdev->dev, "Invalid data address in 'aspeed,lpc-io-reg'\n");
 544                 return -EINVAL;
 545         }
 546
 547         if (rc == 2 && addrs[1] > 0xffff) {
 548                 dev_err(&pdev->dev, "Invalid status address in 'aspeed,lpc-io-reg'\n");
 549                 return -EINVAL;
 550         }
 551
 552         return rc;
 553 }
 554
 555 static int aspeed_kcs_probe(struct platform_device *pdev)
 556 {
 557         struct kcs_bmc_device *kcs_bmc;
 558         struct aspeed_kcs_bmc *priv;
 559         struct device_node *np;
 560         bool have_upstream_irq;
 561         u32 upstream_irq[2];
 562         int rc, channel;
 563         int nr_addrs;
 564         u32 addrs[2];
 565
 566         np = pdev->dev.of_node->parent;
 567         if (!of_device_is_compatible(np, "aspeed,ast2400-lpc-v2") &&
 568             !of_device_is_compatible(np, "aspeed,ast2500-lpc-v2") &&
 569             !of_device_is_compatible(np, "aspeed,ast2600-lpc-v2")) {
 570                 dev_err(&pdev->dev, "unsupported LPC device binding\n");
 571                 return -ENODEV;
 572         }
 573
 574         channel = aspeed_kcs_of_get_channel(pdev);
 575         if (channel < 0)
 576                 return channel;
 577
 578         nr_addrs = aspeed_kcs_of_get_io_address(pdev, addrs);
 579         if (nr_addrs < 0)
 580                 return nr_addrs;
 581
 582         np = pdev->dev.of_node;
 583         rc = of_property_read_u32_array(np, "aspeed,lpc-interrupts", upstream_irq, 2);
 584         if (rc && rc != -EINVAL)
 585                 return -EINVAL;
 586
 587         have_upstream_irq = !rc;
 588
 589         priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
 590         if (!priv)
 591                 return -ENOMEM;
 592
 593         kcs_bmc = &priv->kcs_bmc;
 594         kcs_bmc->dev = &pdev->dev;
 595         kcs_bmc->channel = channel;
 596         kcs_bmc->ioreg = ast_kcs_bmc_ioregs[channel - 1];
 597         kcs_bmc->ops = &aspeed_kcs_ops;
 598
 599         priv->map = syscon_node_to_regmap(pdev->dev.parent->of_node);
 600         if (IS_ERR(priv->map)) {
 601                 dev_err(&pdev->dev, "Couldn't get regmap\n");
 602                 return -ENODEV;
 603         }
 604
 605         spin_lock_init(&priv->obe.lock);
 606         priv->obe.remove = false;
 607         timer_setup(&priv->obe.timer, aspeed_kcs_check_obe, 0);
 608
 609         rc = aspeed_kcs_set_address(kcs_bmc, addrs, nr_addrs);
 610         if (rc)
 611                 return rc;
 612
 613         /* Host to BMC IRQ */
 614         rc = aspeed_kcs_config_downstream_irq(kcs_bmc, pdev);
 615         if (rc)
 616                 return rc;
 617
 618         /* BMC to Host IRQ */
 619         if (have_upstream_irq) {
 620                 rc = aspeed_kcs_config_upstream_irq(priv, upstream_irq[0], upstream_irq[1]);
 621                 if (rc < 0)
 622                         return rc;
 623         } else {
 624                 priv->upstream_irq.mode = aspeed_kcs_irq_none;
 625         }
 626
 627         platform_set_drvdata(pdev, priv);
 628
 629         aspeed_kcs_irq_mask_update(kcs_bmc, (KCS_BMC_EVENT_TYPE_IBF | KCS_BMC_EVENT_TYPE_OBE), 0);
 630         aspeed_kcs_enable_channel(kcs_bmc, true);
 631
 632         rc = kcs_bmc_add_device(&priv->kcs_bmc);
 633         if (rc) {
 634                 dev_warn(&pdev->dev, "Failed to register channel %d: %d\n", kcs_bmc->channel, rc);
 635                 return rc;
 636         }
 637
 638         dev_info(&pdev->dev, "Initialised channel %d at 0x%x\n",
 639                         kcs_bmc->channel, addrs[0]);
 640
 641         return 0;
 642 }
 643
 644 static int aspeed_kcs_remove(struct platform_device *pdev)
 645 {
 646         struct aspeed_kcs_bmc *priv = platform_get_drvdata(pdev);
 647         struct kcs_bmc_device *kcs_bmc = &priv->kcs_bmc;
 648
 649         kcs_bmc_remove_device(kcs_bmc);
 650
 651         aspeed_kcs_enable_channel(kcs_bmc, false);
 652         aspeed_kcs_irq_mask_update(kcs_bmc, (KCS_BMC_EVENT_TYPE_IBF | KCS_BMC_EVENT_TYPE_OBE), 0);
 653
 654         /* Make sure it's proper dead */
 655         spin_lock_irq(&priv->obe.lock);
 656         priv->obe.remove = true;
 657         spin_unlock_irq(&priv->obe.lock);
 658         del_timer_sync(&priv->obe.timer);
 659
 660         return 0;
 661 }
 662
 663 static const struct of_device_id ast_kcs_bmc_match[] = {
 664         { .compatible = "aspeed,ast2400-kcs-bmc-v2" },
 665         { .compatible = "aspeed,ast2500-kcs-bmc-v2" },
 666         { .compatible = "aspeed,ast2600-kcs-bmc" },
 667         { }
 668 };
 669 MODULE_DEVICE_TABLE(of, ast_kcs_bmc_match);
 670
 671 static struct platform_driver ast_kcs_bmc_driver = {
 672         .driver = {
 673                 .name           = DEVICE_NAME,
 674                 .of_match_table = ast_kcs_bmc_match,
 675         },
 676         .probe  = aspeed_kcs_probe,
 677         .remove = aspeed_kcs_remove,
 678 };
 679 module_platform_driver(ast_kcs_bmc_driver);
 680
 681 MODULE_LICENSE("GPL v2");
 682 MODULE_AUTHOR("Haiyue Wang <haiyue.wang@linux.intel.com>");
 683 MODULE_AUTHOR("Andrew Jeffery <andrew@aj.id.au>");
 684 MODULE_DESCRIPTION("Aspeed device interface to the KCS BMC device");