drivers/phy/qualcomm/phy-qcom-eusb2-repeater.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Copyright (c) 2023, Linaro Limited
   4  */
   5
   6 #include <linux/module.h>
   7 #include <linux/platform_device.h>
   8 #include <linux/regulator/consumer.h>
   9 #include <linux/regmap.h>
  10 #include <linux/of.h>
  11 #include <linux/phy/phy.h>
  12
  13 /* eUSB2 status registers */
  14 #define EUSB2_RPTR_STATUS               0x08
  15 #define RPTR_OK                         BIT(7)
  16
  17 /* eUSB2 control registers */
  18 #define EUSB2_EN_CTL1                   0x46
  19 #define EUSB2_RPTR_EN                   BIT(7)
  20
  21 #define EUSB2_FORCE_EN_5                0xe8
  22 #define F_CLK_19P2M_EN                  BIT(6)
  23
  24 #define EUSB2_FORCE_VAL_5               0xeD
  25 #define V_CLK_19P2M_EN                  BIT(6)
  26
  27 #define EUSB2_TUNE_USB2_CROSSOVER       0x50
  28 #define EUSB2_TUNE_IUSB2                0x51
  29 #define EUSB2_TUNE_RES_FSDIF            0x52
  30 #define EUSB2_TUNE_HSDISC               0x53
  31 #define EUSB2_TUNE_SQUELCH_U            0x54
  32 #define EUSB2_TUNE_USB2_SLEW            0x55
  33 #define EUSB2_TUNE_USB2_EQU             0x56
  34 #define EUSB2_TUNE_USB2_PREEM           0x57
  35 #define EUSB2_TUNE_USB2_HS_COMP_CUR     0x58
  36 #define EUSB2_TUNE_EUSB_SLEW            0x59
  37 #define EUSB2_TUNE_EUSB_EQU             0x5A
  38 #define EUSB2_TUNE_EUSB_HS_COMP_CUR     0x5B
  39
  40 enum eusb2_reg_layout {
  41         TUNE_EUSB_HS_COMP_CUR,
  42         TUNE_EUSB_EQU,
  43         TUNE_EUSB_SLEW,
  44         TUNE_USB2_HS_COMP_CUR,
  45         TUNE_USB2_PREEM,
  46         TUNE_USB2_EQU,
  47         TUNE_USB2_SLEW,
  48         TUNE_SQUELCH_U,
  49         TUNE_HSDISC,
  50         TUNE_RES_FSDIF,
  51         TUNE_IUSB2,
  52         TUNE_USB2_CROSSOVER,
  53         NUM_TUNE_FIELDS,
  54
  55         FORCE_VAL_5 = NUM_TUNE_FIELDS,
  56         FORCE_EN_5,
  57
  58         EN_CTL1,
  59
  60         RPTR_STATUS,
  61         LAYOUT_SIZE,
  62 };
  63
  64 struct eusb2_repeater_cfg {
  65         const u32 *init_tbl;
  66         int init_tbl_num;
  67         const char * const *vreg_list;
  68         int num_vregs;
  69 };
  70
  71 struct eusb2_repeater {
  72         struct device *dev;
  73         struct regmap *regmap;
  74         struct phy *phy;
  75         struct regulator_bulk_data *vregs;
  76         const struct eusb2_repeater_cfg *cfg;
  77         u32 base;
  78         enum phy_mode mode;
  79 };
  80
  81 static const char * const pm8550b_vreg_l[] = {
  82         "vdd18", "vdd3",
  83 };
  84
  85 static const u32 pm8550b_init_tbl[NUM_TUNE_FIELDS] = {
  86         [TUNE_IUSB2] = 0x8,
  87         [TUNE_SQUELCH_U] = 0x3,
  88         [TUNE_USB2_PREEM] = 0x5,
  89 };
  90
  91 static const struct eusb2_repeater_cfg pm8550b_eusb2_cfg = {
  92         .init_tbl       = pm8550b_init_tbl,
  93         .init_tbl_num   = ARRAY_SIZE(pm8550b_init_tbl),
  94         .vreg_list      = pm8550b_vreg_l,
  95         .num_vregs      = ARRAY_SIZE(pm8550b_vreg_l),
  96 };
  97
  98 static int eusb2_repeater_init_vregs(struct eusb2_repeater *rptr)
  99 {
 100         int num = rptr->cfg->num_vregs;
 101         struct device *dev = rptr->dev;
 102         int i;
 103
 104         rptr->vregs = devm_kcalloc(dev, num, sizeof(*rptr->vregs), GFP_KERNEL);
 105         if (!rptr->vregs)
 106                 return -ENOMEM;
 107
 108         for (i = 0; i < num; i++)
 109                 rptr->vregs[i].supply = rptr->cfg->vreg_list[i];
 110
 111         return devm_regulator_bulk_get(dev, num, rptr->vregs);
 112 }
 113
 114 static int eusb2_repeater_init(struct phy *phy)
 115 {
 116         struct eusb2_repeater *rptr = phy_get_drvdata(phy);
 117         struct device_node *np = rptr->dev->of_node;
 118         struct regmap *regmap = rptr->regmap;
 119         const u32 *init_tbl = rptr->cfg->init_tbl;
 120         u8 tune_usb2_preem = init_tbl[TUNE_USB2_PREEM];
 121         u8 tune_hsdisc = init_tbl[TUNE_HSDISC];
 122         u8 tune_iusb2 = init_tbl[TUNE_IUSB2];
 123         u32 base = rptr->base;
 124         u32 val;
 125         int ret;
 126
 127         of_property_read_u8(np, "qcom,tune-usb2-amplitude", &tune_iusb2);
 128         of_property_read_u8(np, "qcom,tune-usb2-disc-thres", &tune_hsdisc);
 129         of_property_read_u8(np, "qcom,tune-usb2-preem", &tune_usb2_preem);
 130
 131         ret = regulator_bulk_enable(rptr->cfg->num_vregs, rptr->vregs);
 132         if (ret)
 133                 return ret;
 134
 135         regmap_write(regmap, base + EUSB2_EN_CTL1, EUSB2_RPTR_EN);
 136
 137         regmap_write(regmap, base + EUSB2_TUNE_EUSB_HS_COMP_CUR, init_tbl[TUNE_EUSB_HS_COMP_CUR]);
 138         regmap_write(regmap, base + EUSB2_TUNE_EUSB_EQU, init_tbl[TUNE_EUSB_EQU]);
 139         regmap_write(regmap, base + EUSB2_TUNE_EUSB_SLEW, init_tbl[TUNE_EUSB_SLEW]);
 140         regmap_write(regmap, base + EUSB2_TUNE_USB2_HS_COMP_CUR, init_tbl[TUNE_USB2_HS_COMP_CUR]);
 141         regmap_write(regmap, base + EUSB2_TUNE_USB2_EQU, init_tbl[TUNE_USB2_EQU]);
 142         regmap_write(regmap, base + EUSB2_TUNE_USB2_SLEW, init_tbl[TUNE_USB2_SLEW]);
 143         regmap_write(regmap, base + EUSB2_TUNE_SQUELCH_U, init_tbl[TUNE_SQUELCH_U]);
 144         regmap_write(regmap, base + EUSB2_TUNE_RES_FSDIF, init_tbl[TUNE_RES_FSDIF]);
 145         regmap_write(regmap, base + EUSB2_TUNE_USB2_CROSSOVER, init_tbl[TUNE_USB2_CROSSOVER]);
 146
 147         regmap_write(regmap, base + EUSB2_TUNE_USB2_PREEM, tune_usb2_preem);
 148         regmap_write(regmap, base + EUSB2_TUNE_HSDISC, tune_hsdisc);
 149         regmap_write(regmap, base + EUSB2_TUNE_IUSB2, tune_iusb2);
 150
 151         ret = regmap_read_poll_timeout(regmap, base + EUSB2_RPTR_STATUS, val, val & RPTR_OK, 10, 5);
 152         if (ret)
 153                 dev_err(rptr->dev, "initialization timed-out\n");
 154
 155         return ret;
 156 }
 157
 158 static int eusb2_repeater_set_mode(struct phy *phy,
 159                                    enum phy_mode mode, int submode)
 160 {
 161         struct eusb2_repeater *rptr = phy_get_drvdata(phy);
 162         struct regmap *regmap = rptr->regmap;
 163         u32 base = rptr->base;
 164
 165         switch (mode) {
 166         case PHY_MODE_USB_HOST:
 167                 /*
 168                  * CM.Lx is prohibited when repeater is already into Lx state as
 169                  * per eUSB 1.2 Spec. Below implement software workaround until
 170                  * PHY and controller is fixing seen observation.
 171                  */
 172                 regmap_write(regmap, base + EUSB2_FORCE_EN_5, F_CLK_19P2M_EN);
 173                 regmap_write(regmap, base + EUSB2_FORCE_VAL_5, V_CLK_19P2M_EN);
 174                 break;
 175         case PHY_MODE_USB_DEVICE:
 176                 /*
 177                  * In device mode clear host mode related workaround as there
 178                  * is no repeater reset available, and enable/disable of
 179                  * repeater doesn't clear previous value due to shared
 180                  * regulators (say host <-> device mode switch).
 181                  */
 182                 regmap_write(regmap, base + EUSB2_FORCE_EN_5, 0);
 183                 regmap_write(regmap, base + EUSB2_FORCE_VAL_5, 0);
 184                 break;
 185         default:
 186                 return -EINVAL;
 187         }
 188
 189         return 0;
 190 }
 191
 192 static int eusb2_repeater_exit(struct phy *phy)
 193 {
 194         struct eusb2_repeater *rptr = phy_get_drvdata(phy);
 195
 196         return regulator_bulk_disable(rptr->cfg->num_vregs, rptr->vregs);
 197 }
 198
 199 static const struct phy_ops eusb2_repeater_ops = {
 200         .init           = eusb2_repeater_init,
 201         .exit           = eusb2_repeater_exit,
 202         .set_mode       = eusb2_repeater_set_mode,
 203         .owner          = THIS_MODULE,
 204 };
 205
 206 static int eusb2_repeater_probe(struct platform_device *pdev)
 207 {
 208         struct eusb2_repeater *rptr;
 209         struct device *dev = &pdev->dev;
 210         struct phy_provider *phy_provider;
 211         struct device_node *np = dev->of_node;
 212         u32 res;
 213         int ret;
 214
 215         rptr = devm_kzalloc(dev, sizeof(*rptr), GFP_KERNEL);
 216         if (!rptr)
 217                 return -ENOMEM;
 218
 219         rptr->dev = dev;
 220         dev_set_drvdata(dev, rptr);
 221
 222         rptr->cfg = of_device_get_match_data(dev);
 223         if (!rptr->cfg)
 224                 return -EINVAL;
 225
 226         rptr->regmap = dev_get_regmap(dev->parent, NULL);
 227         if (!rptr->regmap)
 228                 return -ENODEV;
 229
 230         ret = of_property_read_u32(np, "reg", &res);
 231         if (ret < 0)
 232                 return ret;
 233
 234         rptr->base = res;
 235
 236         ret = eusb2_repeater_init_vregs(rptr);
 237         if (ret < 0) {
 238                 dev_err(dev, "unable to get supplies\n");
 239                 return ret;
 240         }
 241
 242         rptr->phy = devm_phy_create(dev, np, &eusb2_repeater_ops);
 243         if (IS_ERR(rptr->phy)) {
 244                 dev_err(dev, "failed to create PHY: %d\n", ret);
 245                 return PTR_ERR(rptr->phy);
 246         }
 247
 248         phy_set_drvdata(rptr->phy, rptr);
 249
 250         phy_provider = devm_of_phy_provider_register(dev, of_phy_simple_xlate);
 251         if (IS_ERR(phy_provider))
 252                 return PTR_ERR(phy_provider);
 253
 254         dev_info(dev, "Registered Qcom-eUSB2 repeater\n");
 255
 256         return 0;
 257 }
 258
 259 static void eusb2_repeater_remove(struct platform_device *pdev)
 260 {
 261         struct eusb2_repeater *rptr = platform_get_drvdata(pdev);
 262
 263         if (!rptr)
 264                 return;
 265
 266         eusb2_repeater_exit(rptr->phy);
 267 }
 268
 269 static const struct of_device_id eusb2_repeater_of_match_table[] = {
 270         {
 271                 .compatible = "qcom,pm8550b-eusb2-repeater",
 272                 .data = &pm8550b_eusb2_cfg,
 273         },
 274         { },
 275 };
 276 MODULE_DEVICE_TABLE(of, eusb2_repeater_of_match_table);
 277
 278 static struct platform_driver eusb2_repeater_driver = {
 279         .probe          = eusb2_repeater_probe,
 280         .remove_new     = eusb2_repeater_remove,
 281         .driver = {
 282                 .name   = "qcom-eusb2-repeater",
 283                 .of_match_table = eusb2_repeater_of_match_table,
 284         },
 285 };
 286
 287 module_platform_driver(eusb2_repeater_driver);
 288
 289 MODULE_DESCRIPTION("Qualcomm PMIC eUSB2 Repeater driver");
 290 MODULE_LICENSE("GPL");