drivers/phy/rockchip/phy-rockchip-dp.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Rockchip DP PHY driver
   4  *
   5  * Copyright (C) 2016 FuZhou Rockchip Co., Ltd.
   6  * Author: Yakir Yang <ykk@@rock-chips.com>
   7  */
   8
   9 #include <linux/clk.h>
  10 #include <linux/mfd/syscon.h>
  11 #include <linux/module.h>
  12 #include <linux/of.h>
  13 #include <linux/phy/phy.h>
  14 #include <linux/platform_device.h>
  15 #include <linux/regmap.h>
  16
  17 #define GRF_SOC_CON12                           0x0274
  18
  19 #define GRF_EDP_REF_CLK_SEL_INTER_HIWORD_MASK   BIT(20)
  20 #define GRF_EDP_REF_CLK_SEL_INTER               BIT(4)
  21
  22 #define GRF_EDP_PHY_SIDDQ_HIWORD_MASK           BIT(21)
  23 #define GRF_EDP_PHY_SIDDQ_ON                    0
  24 #define GRF_EDP_PHY_SIDDQ_OFF                   BIT(5)
  25
  26 struct rockchip_dp_phy {
  27         struct device  *dev;
  28         struct regmap  *grf;
  29         struct clk     *phy_24m;
  30 };
  31
  32 static int rockchip_set_phy_state(struct phy *phy, bool enable)
  33 {
  34         struct rockchip_dp_phy *dp = phy_get_drvdata(phy);
  35         int ret;
  36
  37         if (enable) {
  38                 ret = regmap_write(dp->grf, GRF_SOC_CON12,
  39                                    GRF_EDP_PHY_SIDDQ_HIWORD_MASK |
  40                                    GRF_EDP_PHY_SIDDQ_ON);
  41                 if (ret < 0) {
  42                         dev_err(dp->dev, "Can't enable PHY power %d\n", ret);
  43                         return ret;
  44                 }
  45
  46                 ret = clk_prepare_enable(dp->phy_24m);
  47         } else {
  48                 clk_disable_unprepare(dp->phy_24m);
  49
  50                 ret = regmap_write(dp->grf, GRF_SOC_CON12,
  51                                    GRF_EDP_PHY_SIDDQ_HIWORD_MASK |
  52                                    GRF_EDP_PHY_SIDDQ_OFF);
  53         }
  54
  55         return ret;
  56 }
  57
  58 static int rockchip_dp_phy_power_on(struct phy *phy)
  59 {
  60         return rockchip_set_phy_state(phy, true);
  61 }
  62
  63 static int rockchip_dp_phy_power_off(struct phy *phy)
  64 {
  65         return rockchip_set_phy_state(phy, false);
  66 }
  67
  68 static const struct phy_ops rockchip_dp_phy_ops = {
  69         .power_on       = rockchip_dp_phy_power_on,
  70         .power_off      = rockchip_dp_phy_power_off,
  71         .owner          = THIS_MODULE,
  72 };
  73
  74 static int rockchip_dp_phy_probe(struct platform_device *pdev)
  75 {
  76         struct device *dev = &pdev->dev;
  77         struct device_node *np = dev->of_node;
  78         struct phy_provider *phy_provider;
  79         struct rockchip_dp_phy *dp;
  80         struct phy *phy;
  81         int ret;
  82
  83         if (!np)
  84                 return -ENODEV;
  85
  86         if (!dev->parent || !dev->parent->of_node)
  87                 return -ENODEV;
  88
  89         dp = devm_kzalloc(dev, sizeof(*dp), GFP_KERNEL);
  90         if (!dp)
  91                 return -ENOMEM;
  92
  93         dp->dev = dev;
  94
  95         dp->phy_24m = devm_clk_get(dev, "24m");
  96         if (IS_ERR(dp->phy_24m)) {
  97                 dev_err(dev, "cannot get clock 24m\n");
  98                 return PTR_ERR(dp->phy_24m);
  99         }
 100
 101         ret = clk_set_rate(dp->phy_24m, 24000000);
 102         if (ret < 0) {
 103                 dev_err(dp->dev, "cannot set clock phy_24m %d\n", ret);
 104                 return ret;
 105         }
 106
 107         dp->grf = syscon_node_to_regmap(dev->parent->of_node);
 108         if (IS_ERR(dp->grf)) {
 109                 dev_err(dev, "rk3288-dp needs the General Register Files syscon\n");
 110                 return PTR_ERR(dp->grf);
 111         }
 112
 113         ret = regmap_write(dp->grf, GRF_SOC_CON12, GRF_EDP_REF_CLK_SEL_INTER |
 114                            GRF_EDP_REF_CLK_SEL_INTER_HIWORD_MASK);
 115         if (ret != 0) {
 116                 dev_err(dp->dev, "Could not config GRF edp ref clk: %d\n", ret);
 117                 return ret;
 118         }
 119
 120         phy = devm_phy_create(dev, np, &rockchip_dp_phy_ops);
 121         if (IS_ERR(phy)) {
 122                 dev_err(dev, "failed to create phy\n");
 123                 return PTR_ERR(phy);
 124         }
 125         phy_set_drvdata(phy, dp);
 126
 127         phy_provider = devm_of_phy_provider_register(dev, of_phy_simple_xlate);
 128
 129         return PTR_ERR_OR_ZERO(phy_provider);
 130 }
 131
 132 static const struct of_device_id rockchip_dp_phy_dt_ids[] = {
 133         { .compatible = "rockchip,rk3288-dp-phy" },
 134         {}
 135 };
 136
 137 MODULE_DEVICE_TABLE(of, rockchip_dp_phy_dt_ids);
 138
 139 static struct platform_driver rockchip_dp_phy_driver = {
 140         .probe          = rockchip_dp_phy_probe,
 141         .driver         = {
 142                 .name   = "rockchip-dp-phy",
 143                 .of_match_table = rockchip_dp_phy_dt_ids,
 144         },
 145 };
 146
 147 module_platform_driver(rockchip_dp_phy_driver);
 148
 149 MODULE_AUTHOR("Yakir Yang <ykk@rock-chips.com>");
 150 MODULE_DESCRIPTION("Rockchip DP PHY driver");
 151 MODULE_LICENSE("GPL v2");