drivers/phy/qualcomm/phy-qcom-usb-ss.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Copyright (c) 2012-2014,2017 The Linux Foundation. All rights reserved.
   4  * Copyright (c) 2018-2020, Linaro Limited
   5  */
   6
   7 #include <linux/clk.h>
   8 #include <linux/delay.h>
   9 #include <linux/err.h>
  10 #include <linux/io.h>
  11 #include <linux/kernel.h>
  12 #include <linux/module.h>
  13 #include <linux/of.h>
  14 #include <linux/phy/phy.h>
  15 #include <linux/platform_device.h>
  16 #include <linux/regulator/consumer.h>
  17 #include <linux/reset.h>
  18 #include <linux/slab.h>
  19
  20 #define PHY_CTRL0                       0x6C
  21 #define PHY_CTRL1                       0x70
  22 #define PHY_CTRL2                       0x74
  23 #define PHY_CTRL4                       0x7C
  24
  25 /* PHY_CTRL bits */
  26 #define REF_PHY_EN                      BIT(0)
  27 #define LANE0_PWR_ON                    BIT(2)
  28 #define SWI_PCS_CLK_SEL                 BIT(4)
  29 #define TST_PWR_DOWN                    BIT(4)
  30 #define PHY_RESET                       BIT(7)
  31
  32 #define NUM_BULK_CLKS                   3
  33 #define NUM_BULK_REGS                   2
  34
  35 struct ssphy_priv {
  36         void __iomem *base;
  37         struct device *dev;
  38         struct reset_control *reset_com;
  39         struct reset_control *reset_phy;
  40         struct regulator_bulk_data regs[NUM_BULK_REGS];
  41         struct clk_bulk_data clks[NUM_BULK_CLKS];
  42         enum phy_mode mode;
  43 };
  44
  45 static inline void qcom_ssphy_updatel(void __iomem *addr, u32 mask, u32 val)
  46 {
  47         writel((readl(addr) & ~mask) | val, addr);
  48 }
  49
  50 static int qcom_ssphy_do_reset(struct ssphy_priv *priv)
  51 {
  52         int ret;
  53
  54         if (!priv->reset_com) {
  55                 qcom_ssphy_updatel(priv->base + PHY_CTRL1, PHY_RESET,
  56                                    PHY_RESET);
  57                 usleep_range(10, 20);
  58                 qcom_ssphy_updatel(priv->base + PHY_CTRL1, PHY_RESET, 0);
  59         } else {
  60                 ret = reset_control_assert(priv->reset_com);
  61                 if (ret) {
  62                         dev_err(priv->dev, "Failed to assert reset com\n");
  63                         return ret;
  64                 }
  65
  66                 ret = reset_control_assert(priv->reset_phy);
  67                 if (ret) {
  68                         dev_err(priv->dev, "Failed to assert reset phy\n");
  69                         return ret;
  70                 }
  71
  72                 usleep_range(10, 20);
  73
  74                 ret = reset_control_deassert(priv->reset_com);
  75                 if (ret) {
  76                         dev_err(priv->dev, "Failed to deassert reset com\n");
  77                         return ret;
  78                 }
  79
  80                 ret = reset_control_deassert(priv->reset_phy);
  81                 if (ret) {
  82                         dev_err(priv->dev, "Failed to deassert reset phy\n");
  83                         return ret;
  84                 }
  85         }
  86
  87         return 0;
  88 }
  89
  90 static int qcom_ssphy_power_on(struct phy *phy)
  91 {
  92         struct ssphy_priv *priv = phy_get_drvdata(phy);
  93         int ret;
  94
  95         ret = regulator_bulk_enable(NUM_BULK_REGS, priv->regs);
  96         if (ret)
  97                 return ret;
  98
  99         ret = clk_bulk_prepare_enable(NUM_BULK_CLKS, priv->clks);
 100         if (ret)
 101                 goto err_disable_regulator;
 102
 103         ret = qcom_ssphy_do_reset(priv);
 104         if (ret)
 105                 goto err_disable_clock;
 106
 107         writeb(SWI_PCS_CLK_SEL, priv->base + PHY_CTRL0);
 108         qcom_ssphy_updatel(priv->base + PHY_CTRL4, LANE0_PWR_ON, LANE0_PWR_ON);
 109         qcom_ssphy_updatel(priv->base + PHY_CTRL2, REF_PHY_EN, REF_PHY_EN);
 110         qcom_ssphy_updatel(priv->base + PHY_CTRL4, TST_PWR_DOWN, 0);
 111
 112         return 0;
 113 err_disable_clock:
 114         clk_bulk_disable_unprepare(NUM_BULK_CLKS, priv->clks);
 115 err_disable_regulator:
 116         regulator_bulk_disable(NUM_BULK_REGS, priv->regs);
 117
 118         return ret;
 119 }
 120
 121 static int qcom_ssphy_power_off(struct phy *phy)
 122 {
 123         struct ssphy_priv *priv = phy_get_drvdata(phy);
 124
 125         qcom_ssphy_updatel(priv->base + PHY_CTRL4, LANE0_PWR_ON, 0);
 126         qcom_ssphy_updatel(priv->base + PHY_CTRL2, REF_PHY_EN, 0);
 127         qcom_ssphy_updatel(priv->base + PHY_CTRL4, TST_PWR_DOWN, TST_PWR_DOWN);
 128
 129         clk_bulk_disable_unprepare(NUM_BULK_CLKS, priv->clks);
 130         regulator_bulk_disable(NUM_BULK_REGS, priv->regs);
 131
 132         return 0;
 133 }
 134
 135 static int qcom_ssphy_init_clock(struct ssphy_priv *priv)
 136 {
 137         priv->clks[0].id = "ref";
 138         priv->clks[1].id = "ahb";
 139         priv->clks[2].id = "pipe";
 140
 141         return devm_clk_bulk_get(priv->dev, NUM_BULK_CLKS, priv->clks);
 142 }
 143
 144 static int qcom_ssphy_init_regulator(struct ssphy_priv *priv)
 145 {
 146         int ret;
 147
 148         priv->regs[0].supply = "vdd";
 149         priv->regs[1].supply = "vdda1p8";
 150         ret = devm_regulator_bulk_get(priv->dev, NUM_BULK_REGS, priv->regs);
 151         if (ret) {
 152                 if (ret != -EPROBE_DEFER)
 153                         dev_err(priv->dev, "Failed to get regulators\n");
 154                 return ret;
 155         }
 156
 157         return ret;
 158 }
 159
 160 static int qcom_ssphy_init_reset(struct ssphy_priv *priv)
 161 {
 162         priv->reset_com = devm_reset_control_get_optional_exclusive(priv->dev, "com");
 163         if (IS_ERR(priv->reset_com)) {
 164                 dev_err(priv->dev, "Failed to get reset control com\n");
 165                 return PTR_ERR(priv->reset_com);
 166         }
 167
 168         if (priv->reset_com) {
 169                 /* if reset_com is present, reset_phy is no longer optional */
 170                 priv->reset_phy = devm_reset_control_get_exclusive(priv->dev, "phy");
 171                 if (IS_ERR(priv->reset_phy)) {
 172                         dev_err(priv->dev, "Failed to get reset control phy\n");
 173                         return PTR_ERR(priv->reset_phy);
 174                 }
 175         }
 176
 177         return 0;
 178 }
 179
 180 static const struct phy_ops qcom_ssphy_ops = {
 181         .power_off = qcom_ssphy_power_off,
 182         .power_on = qcom_ssphy_power_on,
 183         .owner = THIS_MODULE,
 184 };
 185
 186 static int qcom_ssphy_probe(struct platform_device *pdev)
 187 {
 188         struct device *dev = &pdev->dev;
 189         struct phy_provider *provider;
 190         struct ssphy_priv *priv;
 191         struct phy *phy;
 192         int ret;
 193
 194         priv = devm_kzalloc(dev, sizeof(struct ssphy_priv), GFP_KERNEL);
 195         if (!priv)
 196                 return -ENOMEM;
 197
 198         priv->dev = dev;
 199         priv->mode = PHY_MODE_INVALID;
 200
 201         priv->base = devm_platform_ioremap_resource(pdev, 0);
 202         if (IS_ERR(priv->base))
 203                 return PTR_ERR(priv->base);
 204
 205         ret = qcom_ssphy_init_clock(priv);
 206         if (ret)
 207                 return ret;
 208
 209         ret = qcom_ssphy_init_reset(priv);
 210         if (ret)
 211                 return ret;
 212
 213         ret = qcom_ssphy_init_regulator(priv);
 214         if (ret)
 215                 return ret;
 216
 217         phy = devm_phy_create(dev, dev->of_node, &qcom_ssphy_ops);
 218         if (IS_ERR(phy)) {
 219                 dev_err(dev, "Failed to create the SS phy\n");
 220                 return PTR_ERR(phy);
 221         }
 222
 223         phy_set_drvdata(phy, priv);
 224
 225         provider = devm_of_phy_provider_register(dev, of_phy_simple_xlate);
 226
 227         return PTR_ERR_OR_ZERO(provider);
 228 }
 229
 230 static const struct of_device_id qcom_ssphy_match[] = {
 231         { .compatible = "qcom,usb-ss-28nm-phy", },
 232         { },
 233 };
 234 MODULE_DEVICE_TABLE(of, qcom_ssphy_match);
 235
 236 static struct platform_driver qcom_ssphy_driver = {
 237         .probe          = qcom_ssphy_probe,
 238         .driver = {
 239                 .name   = "qcom-usb-ssphy",
 240                 .of_match_table = qcom_ssphy_match,
 241         },
 242 };
 243 module_platform_driver(qcom_ssphy_driver);
 244
 245 MODULE_DESCRIPTION("Qualcomm SuperSpeed USB PHY driver");
 246 MODULE_LICENSE("GPL v2");