linux/drivers/phy/amlogic/phy-meson-gxl-usb2.c
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   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 * Meson GXL and GXM USB2 PHY driver
   4 *
   5 * Copyright (C) 2017 Martin Blumenstingl <martin.blumenstingl@googlemail.com>
   6 */
   7
   8#include <linux/clk.h>
   9#include <linux/delay.h>
  10#include <linux/io.h>
  11#include <linux/module.h>
  12#include <linux/of_device.h>
  13#include <linux/regmap.h>
  14#include <linux/reset.h>
  15#include <linux/phy/phy.h>
  16#include <linux/platform_device.h>
  17
  18/* bits [31:27] are read-only */
  19#define U2P_R0                                                  0x0
  20        #define U2P_R0_BYPASS_SEL                               BIT(0)
  21        #define U2P_R0_BYPASS_DM_EN                             BIT(1)
  22        #define U2P_R0_BYPASS_DP_EN                             BIT(2)
  23        #define U2P_R0_TXBITSTUFF_ENH                           BIT(3)
  24        #define U2P_R0_TXBITSTUFF_EN                            BIT(4)
  25        #define U2P_R0_DM_PULLDOWN                              BIT(5)
  26        #define U2P_R0_DP_PULLDOWN                              BIT(6)
  27        #define U2P_R0_DP_VBUS_VLD_EXT_SEL                      BIT(7)
  28        #define U2P_R0_DP_VBUS_VLD_EXT                          BIT(8)
  29        #define U2P_R0_ADP_PRB_EN                               BIT(9)
  30        #define U2P_R0_ADP_DISCHARGE                            BIT(10)
  31        #define U2P_R0_ADP_CHARGE                               BIT(11)
  32        #define U2P_R0_DRV_VBUS                                 BIT(12)
  33        #define U2P_R0_ID_PULLUP                                BIT(13)
  34        #define U2P_R0_LOOPBACK_EN_B                            BIT(14)
  35        #define U2P_R0_OTG_DISABLE                              BIT(15)
  36        #define U2P_R0_COMMON_ONN                               BIT(16)
  37        #define U2P_R0_FSEL_MASK                                GENMASK(19, 17)
  38        #define U2P_R0_REF_CLK_SEL_MASK                         GENMASK(21, 20)
  39        #define U2P_R0_POWER_ON_RESET                           BIT(22)
  40        #define U2P_R0_V_ATE_TEST_EN_B_MASK                     GENMASK(24, 23)
  41        #define U2P_R0_ID_SET_ID_DQ                             BIT(25)
  42        #define U2P_R0_ATE_RESET                                BIT(26)
  43        #define U2P_R0_FSV_MINUS                                BIT(27)
  44        #define U2P_R0_FSV_PLUS                                 BIT(28)
  45        #define U2P_R0_BYPASS_DM_DATA                           BIT(29)
  46        #define U2P_R0_BYPASS_DP_DATA                           BIT(30)
  47
  48#define U2P_R1                                                  0x4
  49        #define U2P_R1_BURN_IN_TEST                             BIT(0)
  50        #define U2P_R1_ACA_ENABLE                               BIT(1)
  51        #define U2P_R1_DCD_ENABLE                               BIT(2)
  52        #define U2P_R1_VDAT_SRC_EN_B                            BIT(3)
  53        #define U2P_R1_VDAT_DET_EN_B                            BIT(4)
  54        #define U2P_R1_CHARGES_SEL                              BIT(5)
  55        #define U2P_R1_TX_PREEMP_PULSE_TUNE                     BIT(6)
  56        #define U2P_R1_TX_PREEMP_AMP_TUNE_MASK                  GENMASK(8, 7)
  57        #define U2P_R1_TX_RES_TUNE_MASK                         GENMASK(10, 9)
  58        #define U2P_R1_TX_RISE_TUNE_MASK                        GENMASK(12, 11)
  59        #define U2P_R1_TX_VREF_TUNE_MASK                        GENMASK(16, 13)
  60        #define U2P_R1_TX_FSLS_TUNE_MASK                        GENMASK(20, 17)
  61        #define U2P_R1_TX_HSXV_TUNE_MASK                        GENMASK(22, 21)
  62        #define U2P_R1_OTG_TUNE_MASK                            GENMASK(25, 23)
  63        #define U2P_R1_SQRX_TUNE_MASK                           GENMASK(28, 26)
  64        #define U2P_R1_COMP_DIS_TUNE_MASK                       GENMASK(31, 29)
  65
  66/* bits [31:14] are read-only */
  67#define U2P_R2                                                  0x8
  68        #define U2P_R2_TESTDATA_IN_MASK                         GENMASK(7, 0)
  69        #define U2P_R2_TESTADDR_MASK                            GENMASK(11, 8)
  70        #define U2P_R2_TESTDATA_OUT_SEL                         BIT(12)
  71        #define U2P_R2_TESTCLK                                  BIT(13)
  72        #define U2P_R2_TESTDATA_OUT_MASK                        GENMASK(17, 14)
  73        #define U2P_R2_ACA_PIN_RANGE_C                          BIT(18)
  74        #define U2P_R2_ACA_PIN_RANGE_B                          BIT(19)
  75        #define U2P_R2_ACA_PIN_RANGE_A                          BIT(20)
  76        #define U2P_R2_ACA_PIN_GND                              BIT(21)
  77        #define U2P_R2_ACA_PIN_FLOAT                            BIT(22)
  78        #define U2P_R2_CHARGE_DETECT                            BIT(23)
  79        #define U2P_R2_DEVICE_SESSION_VALID                     BIT(24)
  80        #define U2P_R2_ADP_PROBE                                BIT(25)
  81        #define U2P_R2_ADP_SENSE                                BIT(26)
  82        #define U2P_R2_SESSION_END                              BIT(27)
  83        #define U2P_R2_VBUS_VALID                               BIT(28)
  84        #define U2P_R2_B_VALID                                  BIT(29)
  85        #define U2P_R2_A_VALID                                  BIT(30)
  86        #define U2P_R2_ID_DIG                                   BIT(31)
  87
  88#define U2P_R3                                                  0xc
  89
  90#define RESET_COMPLETE_TIME                             500
  91
  92struct phy_meson_gxl_usb2_priv {
  93        struct regmap           *regmap;
  94        enum phy_mode           mode;
  95        int                     is_enabled;
  96        struct clk              *clk;
  97        struct reset_control    *reset;
  98};
  99
 100static const struct regmap_config phy_meson_gxl_usb2_regmap_conf = {
 101        .reg_bits = 8,
 102        .val_bits = 32,
 103        .reg_stride = 4,
 104        .max_register = U2P_R3,
 105};
 106
 107static int phy_meson_gxl_usb2_init(struct phy *phy)
 108{
 109        struct phy_meson_gxl_usb2_priv *priv = phy_get_drvdata(phy);
 110        int ret;
 111
 112        ret = reset_control_reset(priv->reset);
 113        if (ret)
 114                return ret;
 115
 116        ret = clk_prepare_enable(priv->clk);
 117        if (ret)
 118                return ret;
 119
 120        return 0;
 121}
 122
 123static int phy_meson_gxl_usb2_exit(struct phy *phy)
 124{
 125        struct phy_meson_gxl_usb2_priv *priv = phy_get_drvdata(phy);
 126
 127        clk_disable_unprepare(priv->clk);
 128
 129        return 0;
 130}
 131
 132static int phy_meson_gxl_usb2_reset(struct phy *phy)
 133{
 134        struct phy_meson_gxl_usb2_priv *priv = phy_get_drvdata(phy);
 135
 136        if (priv->is_enabled) {
 137                /* reset the PHY and wait until settings are stabilized */
 138                regmap_update_bits(priv->regmap, U2P_R0, U2P_R0_POWER_ON_RESET,
 139                                   U2P_R0_POWER_ON_RESET);
 140                udelay(RESET_COMPLETE_TIME);
 141                regmap_update_bits(priv->regmap, U2P_R0, U2P_R0_POWER_ON_RESET,
 142                                   0);
 143                udelay(RESET_COMPLETE_TIME);
 144        }
 145
 146        return 0;
 147}
 148
 149static int phy_meson_gxl_usb2_set_mode(struct phy *phy,
 150                                       enum phy_mode mode, int submode)
 151{
 152        struct phy_meson_gxl_usb2_priv *priv = phy_get_drvdata(phy);
 153
 154        switch (mode) {
 155        case PHY_MODE_USB_HOST:
 156        case PHY_MODE_USB_OTG:
 157                regmap_update_bits(priv->regmap, U2P_R0, U2P_R0_DM_PULLDOWN,
 158                                   U2P_R0_DM_PULLDOWN);
 159                regmap_update_bits(priv->regmap, U2P_R0, U2P_R0_DP_PULLDOWN,
 160                                   U2P_R0_DP_PULLDOWN);
 161                regmap_update_bits(priv->regmap, U2P_R0, U2P_R0_ID_PULLUP,
 162                                   U2P_R0_ID_PULLUP);
 163                break;
 164
 165        case PHY_MODE_USB_DEVICE:
 166                regmap_update_bits(priv->regmap, U2P_R0, U2P_R0_DM_PULLDOWN,
 167                                   0);
 168                regmap_update_bits(priv->regmap, U2P_R0, U2P_R0_DP_PULLDOWN,
 169                                   0);
 170                regmap_update_bits(priv->regmap, U2P_R0, U2P_R0_ID_PULLUP,
 171                                   U2P_R0_ID_PULLUP);
 172                break;
 173
 174        default:
 175                return -EINVAL;
 176        }
 177
 178        phy_meson_gxl_usb2_reset(phy);
 179
 180        priv->mode = mode;
 181
 182        return 0;
 183}
 184
 185static int phy_meson_gxl_usb2_power_off(struct phy *phy)
 186{
 187        struct phy_meson_gxl_usb2_priv *priv = phy_get_drvdata(phy);
 188
 189        priv->is_enabled = 0;
 190
 191        /* power off the PHY by putting it into reset mode */
 192        regmap_update_bits(priv->regmap, U2P_R0, U2P_R0_POWER_ON_RESET,
 193                           U2P_R0_POWER_ON_RESET);
 194
 195        return 0;
 196}
 197
 198static int phy_meson_gxl_usb2_power_on(struct phy *phy)
 199{
 200        struct phy_meson_gxl_usb2_priv *priv = phy_get_drvdata(phy);
 201        int ret;
 202
 203        priv->is_enabled = 1;
 204
 205        /* power on the PHY by taking it out of reset mode */
 206        regmap_update_bits(priv->regmap, U2P_R0, U2P_R0_POWER_ON_RESET, 0);
 207
 208        ret = phy_meson_gxl_usb2_set_mode(phy, priv->mode, 0);
 209        if (ret) {
 210                phy_meson_gxl_usb2_power_off(phy);
 211
 212                dev_err(&phy->dev, "Failed to initialize PHY with mode %d\n",
 213                        priv->mode);
 214                return ret;
 215        }
 216
 217        return 0;
 218}
 219
 220static const struct phy_ops phy_meson_gxl_usb2_ops = {
 221        .init           = phy_meson_gxl_usb2_init,
 222        .exit           = phy_meson_gxl_usb2_exit,
 223        .power_on       = phy_meson_gxl_usb2_power_on,
 224        .power_off      = phy_meson_gxl_usb2_power_off,
 225        .set_mode       = phy_meson_gxl_usb2_set_mode,
 226        .reset          = phy_meson_gxl_usb2_reset,
 227        .owner          = THIS_MODULE,
 228};
 229
 230static int phy_meson_gxl_usb2_probe(struct platform_device *pdev)
 231{
 232        struct device *dev = &pdev->dev;
 233        struct phy_provider *phy_provider;
 234        struct phy_meson_gxl_usb2_priv *priv;
 235        struct phy *phy;
 236        void __iomem *base;
 237        int ret;
 238
 239        priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
 240        if (!priv)
 241                return -ENOMEM;
 242
 243        platform_set_drvdata(pdev, priv);
 244
 245        base = devm_platform_ioremap_resource(pdev, 0);
 246        if (IS_ERR(base))
 247                return PTR_ERR(base);
 248
 249        /* start in host mode */
 250        priv->mode = PHY_MODE_USB_HOST;
 251
 252        priv->regmap = devm_regmap_init_mmio(dev, base,
 253                                             &phy_meson_gxl_usb2_regmap_conf);
 254        if (IS_ERR(priv->regmap))
 255                return PTR_ERR(priv->regmap);
 256
 257        priv->clk = devm_clk_get_optional(dev, "phy");
 258        if (IS_ERR(priv->clk))
 259                return PTR_ERR(priv->clk);
 260
 261        priv->reset = devm_reset_control_get_optional_shared(dev, "phy");
 262        if (IS_ERR(priv->reset))
 263                return PTR_ERR(priv->reset);
 264
 265        phy = devm_phy_create(dev, NULL, &phy_meson_gxl_usb2_ops);
 266        if (IS_ERR(phy)) {
 267                ret = PTR_ERR(phy);
 268                if (ret != -EPROBE_DEFER)
 269                        dev_err(dev, "failed to create PHY\n");
 270
 271                return ret;
 272        }
 273
 274        phy_set_drvdata(phy, priv);
 275
 276        phy_provider = devm_of_phy_provider_register(dev, of_phy_simple_xlate);
 277
 278        return PTR_ERR_OR_ZERO(phy_provider);
 279}
 280
 281static const struct of_device_id phy_meson_gxl_usb2_of_match[] = {
 282        { .compatible = "amlogic,meson-gxl-usb2-phy", },
 283        { },
 284};
 285MODULE_DEVICE_TABLE(of, phy_meson_gxl_usb2_of_match);
 286
 287static struct platform_driver phy_meson_gxl_usb2_driver = {
 288        .probe  = phy_meson_gxl_usb2_probe,
 289        .driver = {
 290                .name           = "phy-meson-gxl-usb2",
 291                .of_match_table = phy_meson_gxl_usb2_of_match,
 292        },
 293};
 294module_platform_driver(phy_meson_gxl_usb2_driver);
 295
 296MODULE_AUTHOR("Martin Blumenstingl <martin.blumenstingl@googlemail.com>");
 297MODULE_DESCRIPTION("Meson GXL and GXM USB2 PHY driver");
 298MODULE_LICENSE("GPL v2");
 299