drivers/phy/mediatek/phy-mtk-dp.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * MediaTek DisplayPort PHY driver
   4  *
   5  * Copyright (c) 2022, BayLibre Inc.
   6  * Copyright (c) 2022, MediaTek Inc.
   7  */
   8
   9 #include <linux/delay.h>
  10 #include <linux/io.h>
  11 #include <linux/mfd/syscon.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 PHY_OFFSET                      0x1000
  18
  19 #define MTK_DP_PHY_DIG_PLL_CTL_1        (PHY_OFFSET + 0x14)
  20 #define TPLL_SSC_EN                     BIT(3)
  21
  22 #define MTK_DP_PHY_DIG_BIT_RATE         (PHY_OFFSET + 0x3C)
  23 #define BIT_RATE_RBR                    0
  24 #define BIT_RATE_HBR                    1
  25 #define BIT_RATE_HBR2                   2
  26 #define BIT_RATE_HBR3                   3
  27
  28 #define MTK_DP_PHY_DIG_SW_RST           (PHY_OFFSET + 0x38)
  29 #define DP_GLB_SW_RST_PHYD              BIT(0)
  30
  31 #define MTK_DP_LANE0_DRIVING_PARAM_3            (PHY_OFFSET + 0x138)
  32 #define MTK_DP_LANE1_DRIVING_PARAM_3            (PHY_OFFSET + 0x238)
  33 #define MTK_DP_LANE2_DRIVING_PARAM_3            (PHY_OFFSET + 0x338)
  34 #define MTK_DP_LANE3_DRIVING_PARAM_3            (PHY_OFFSET + 0x438)
  35 #define XTP_LN_TX_LCTXC0_SW0_PRE0_DEFAULT       BIT(4)
  36 #define XTP_LN_TX_LCTXC0_SW0_PRE1_DEFAULT       (BIT(10) | BIT(12))
  37 #define XTP_LN_TX_LCTXC0_SW0_PRE2_DEFAULT       GENMASK(20, 19)
  38 #define XTP_LN_TX_LCTXC0_SW0_PRE3_DEFAULT       GENMASK(29, 29)
  39 #define DRIVING_PARAM_3_DEFAULT (XTP_LN_TX_LCTXC0_SW0_PRE0_DEFAULT | \
  40                                  XTP_LN_TX_LCTXC0_SW0_PRE1_DEFAULT | \
  41                                  XTP_LN_TX_LCTXC0_SW0_PRE2_DEFAULT | \
  42                                  XTP_LN_TX_LCTXC0_SW0_PRE3_DEFAULT)
  43
  44 #define XTP_LN_TX_LCTXC0_SW1_PRE0_DEFAULT       GENMASK(4, 3)
  45 #define XTP_LN_TX_LCTXC0_SW1_PRE1_DEFAULT       GENMASK(12, 9)
  46 #define XTP_LN_TX_LCTXC0_SW1_PRE2_DEFAULT       (BIT(18) | BIT(21))
  47 #define XTP_LN_TX_LCTXC0_SW2_PRE0_DEFAULT       GENMASK(29, 29)
  48 #define DRIVING_PARAM_4_DEFAULT (XTP_LN_TX_LCTXC0_SW1_PRE0_DEFAULT | \
  49                                  XTP_LN_TX_LCTXC0_SW1_PRE1_DEFAULT | \
  50                                  XTP_LN_TX_LCTXC0_SW1_PRE2_DEFAULT | \
  51                                  XTP_LN_TX_LCTXC0_SW2_PRE0_DEFAULT)
  52
  53 #define XTP_LN_TX_LCTXC0_SW2_PRE1_DEFAULT       (BIT(3) | BIT(5))
  54 #define XTP_LN_TX_LCTXC0_SW3_PRE0_DEFAULT       GENMASK(13, 12)
  55 #define DRIVING_PARAM_5_DEFAULT (XTP_LN_TX_LCTXC0_SW2_PRE1_DEFAULT | \
  56                                  XTP_LN_TX_LCTXC0_SW3_PRE0_DEFAULT)
  57
  58 #define XTP_LN_TX_LCTXCP1_SW0_PRE0_DEFAULT      0
  59 #define XTP_LN_TX_LCTXCP1_SW0_PRE1_DEFAULT      GENMASK(10, 10)
  60 #define XTP_LN_TX_LCTXCP1_SW0_PRE2_DEFAULT      GENMASK(19, 19)
  61 #define XTP_LN_TX_LCTXCP1_SW0_PRE3_DEFAULT      GENMASK(28, 28)
  62 #define DRIVING_PARAM_6_DEFAULT (XTP_LN_TX_LCTXCP1_SW0_PRE0_DEFAULT | \
  63                                  XTP_LN_TX_LCTXCP1_SW0_PRE1_DEFAULT | \
  64                                  XTP_LN_TX_LCTXCP1_SW0_PRE2_DEFAULT | \
  65                                  XTP_LN_TX_LCTXCP1_SW0_PRE3_DEFAULT)
  66
  67 #define XTP_LN_TX_LCTXCP1_SW1_PRE0_DEFAULT      0
  68 #define XTP_LN_TX_LCTXCP1_SW1_PRE1_DEFAULT      GENMASK(10, 9)
  69 #define XTP_LN_TX_LCTXCP1_SW1_PRE2_DEFAULT      GENMASK(19, 18)
  70 #define XTP_LN_TX_LCTXCP1_SW2_PRE0_DEFAULT      0
  71 #define DRIVING_PARAM_7_DEFAULT (XTP_LN_TX_LCTXCP1_SW1_PRE0_DEFAULT | \
  72                                  XTP_LN_TX_LCTXCP1_SW1_PRE1_DEFAULT | \
  73                                  XTP_LN_TX_LCTXCP1_SW1_PRE2_DEFAULT | \
  74                                  XTP_LN_TX_LCTXCP1_SW2_PRE0_DEFAULT)
  75
  76 #define XTP_LN_TX_LCTXCP1_SW2_PRE1_DEFAULT      GENMASK(3, 3)
  77 #define XTP_LN_TX_LCTXCP1_SW3_PRE0_DEFAULT      0
  78 #define DRIVING_PARAM_8_DEFAULT (XTP_LN_TX_LCTXCP1_SW2_PRE1_DEFAULT | \
  79                                  XTP_LN_TX_LCTXCP1_SW3_PRE0_DEFAULT)
  80
  81 struct mtk_dp_phy {
  82         struct regmap *regs;
  83 };
  84
  85 static int mtk_dp_phy_init(struct phy *phy)
  86 {
  87         struct mtk_dp_phy *dp_phy = phy_get_drvdata(phy);
  88         static const u32 driving_params[] = {
  89                 DRIVING_PARAM_3_DEFAULT,
  90                 DRIVING_PARAM_4_DEFAULT,
  91                 DRIVING_PARAM_5_DEFAULT,
  92                 DRIVING_PARAM_6_DEFAULT,
  93                 DRIVING_PARAM_7_DEFAULT,
  94                 DRIVING_PARAM_8_DEFAULT
  95         };
  96
  97         regmap_bulk_write(dp_phy->regs, MTK_DP_LANE0_DRIVING_PARAM_3,
  98                           driving_params, ARRAY_SIZE(driving_params));
  99         regmap_bulk_write(dp_phy->regs, MTK_DP_LANE1_DRIVING_PARAM_3,
 100                           driving_params, ARRAY_SIZE(driving_params));
 101         regmap_bulk_write(dp_phy->regs, MTK_DP_LANE2_DRIVING_PARAM_3,
 102                           driving_params, ARRAY_SIZE(driving_params));
 103         regmap_bulk_write(dp_phy->regs, MTK_DP_LANE3_DRIVING_PARAM_3,
 104                           driving_params, ARRAY_SIZE(driving_params));
 105
 106         return 0;
 107 }
 108
 109 static int mtk_dp_phy_configure(struct phy *phy, union phy_configure_opts *opts)
 110 {
 111         struct mtk_dp_phy *dp_phy = phy_get_drvdata(phy);
 112         u32 val;
 113
 114         if (opts->dp.set_rate) {
 115                 switch (opts->dp.link_rate) {
 116                 default:
 117                         dev_err(&phy->dev,
 118                                 "Implementation error, unknown linkrate %x\n",
 119                                 opts->dp.link_rate);
 120                         return -EINVAL;
 121                 case 1620:
 122                         val = BIT_RATE_RBR;
 123                         break;
 124                 case 2700:
 125                         val = BIT_RATE_HBR;
 126                         break;
 127                 case 5400:
 128                         val = BIT_RATE_HBR2;
 129                         break;
 130                 case 8100:
 131                         val = BIT_RATE_HBR3;
 132                         break;
 133                 }
 134                 regmap_write(dp_phy->regs, MTK_DP_PHY_DIG_BIT_RATE, val);
 135         }
 136
 137         regmap_update_bits(dp_phy->regs, MTK_DP_PHY_DIG_PLL_CTL_1,
 138                            TPLL_SSC_EN, opts->dp.ssc ? TPLL_SSC_EN : 0);
 139
 140         return 0;
 141 }
 142
 143 static int mtk_dp_phy_reset(struct phy *phy)
 144 {
 145         struct mtk_dp_phy *dp_phy = phy_get_drvdata(phy);
 146
 147         regmap_update_bits(dp_phy->regs, MTK_DP_PHY_DIG_SW_RST,
 148                            DP_GLB_SW_RST_PHYD, 0);
 149         usleep_range(50, 200);
 150         regmap_update_bits(dp_phy->regs, MTK_DP_PHY_DIG_SW_RST,
 151                            DP_GLB_SW_RST_PHYD, 1);
 152
 153         return 0;
 154 }
 155
 156 static const struct phy_ops mtk_dp_phy_dev_ops = {
 157         .init = mtk_dp_phy_init,
 158         .configure = mtk_dp_phy_configure,
 159         .reset = mtk_dp_phy_reset,
 160         .owner = THIS_MODULE,
 161 };
 162
 163 static int mtk_dp_phy_probe(struct platform_device *pdev)
 164 {
 165         struct device *dev = &pdev->dev;
 166         struct mtk_dp_phy *dp_phy;
 167         struct phy *phy;
 168         struct regmap *regs;
 169
 170         regs = *(struct regmap **)dev->platform_data;
 171         if (!regs)
 172                 return dev_err_probe(dev, EINVAL,
 173                                      "No data passed, requires struct regmap**\n");
 174
 175         dp_phy = devm_kzalloc(dev, sizeof(*dp_phy), GFP_KERNEL);
 176         if (!dp_phy)
 177                 return -ENOMEM;
 178
 179         dp_phy->regs = regs;
 180         phy = devm_phy_create(dev, NULL, &mtk_dp_phy_dev_ops);
 181         if (IS_ERR(phy))
 182                 return dev_err_probe(dev, PTR_ERR(phy),
 183                                      "Failed to create DP PHY\n");
 184
 185         phy_set_drvdata(phy, dp_phy);
 186         if (!dev->of_node)
 187                 phy_create_lookup(phy, "dp", dev_name(dev));
 188
 189         return 0;
 190 }
 191
 192 static struct platform_driver mtk_dp_phy_driver = {
 193         .probe = mtk_dp_phy_probe,
 194         .driver = {
 195                 .name = "mediatek-dp-phy",
 196         },
 197 };
 198 module_platform_driver(mtk_dp_phy_driver);
 199
 200 MODULE_AUTHOR("Markus Schneider-Pargmann <msp@baylibre.com>");
 201 MODULE_DESCRIPTION("MediaTek DP PHY Driver");
 202 MODULE_LICENSE("GPL");