kernel/drivers/phy/phy-exynos-mipi-video.c

   1 /*
   2  * Samsung S5P/EXYNOS SoC series MIPI CSIS/DSIM DPHY driver
   3  *
   4  * Copyright (C) 2013 Samsung Electronics Co., Ltd.
   5  * Author: Sylwester Nawrocki <s.nawrocki@samsung.com>
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License version 2 as
   9  * published by the Free Software Foundation.
  10  */
  11
  12 #include <linux/err.h>
  13 #include <linux/io.h>
  14 #include <linux/kernel.h>
  15 #include <linux/mfd/syscon/exynos4-pmu.h>
  16 #include <linux/module.h>
  17 #include <linux/of.h>
  18 #include <linux/of_address.h>
  19 #include <linux/phy/phy.h>
  20 #include <linux/platform_device.h>
  21 #include <linux/regmap.h>
  22 #include <linux/spinlock.h>
  23 #include <linux/mfd/syscon.h>
  24
  25 /* MIPI_PHYn_CONTROL reg. offset (for base address from ioremap): n = 0..1 */
  26 #define EXYNOS_MIPI_PHY_CONTROL(n)      ((n) * 4)
  27
  28 enum exynos_mipi_phy_id {
  29         EXYNOS_MIPI_PHY_ID_CSIS0,
  30         EXYNOS_MIPI_PHY_ID_DSIM0,
  31         EXYNOS_MIPI_PHY_ID_CSIS1,
  32         EXYNOS_MIPI_PHY_ID_DSIM1,
  33         EXYNOS_MIPI_PHYS_NUM
  34 };
  35
  36 #define is_mipi_dsim_phy_id(id) \
  37         ((id) == EXYNOS_MIPI_PHY_ID_DSIM0 || (id) == EXYNOS_MIPI_PHY_ID_DSIM1)
  38
  39 struct exynos_mipi_video_phy {
  40         struct video_phy_desc {
  41                 struct phy *phy;
  42                 unsigned int index;
  43         } phys[EXYNOS_MIPI_PHYS_NUM];
  44         spinlock_t slock;
  45         void __iomem *regs;
  46         struct regmap *regmap;
  47 };
  48
  49 static int __set_phy_state(struct exynos_mipi_video_phy *state,
  50                         enum exynos_mipi_phy_id id, unsigned int on)
  51 {
  52         const unsigned int offset = EXYNOS4_MIPI_PHY_CONTROL(id / 2);
  53         void __iomem *addr;
  54         u32 val, reset;
  55
  56         if (is_mipi_dsim_phy_id(id))
  57                 reset = EXYNOS4_MIPI_PHY_MRESETN;
  58         else
  59                 reset = EXYNOS4_MIPI_PHY_SRESETN;
  60
  61         spin_lock(&state->slock);
  62
  63         if (!IS_ERR(state->regmap)) {
  64                 regmap_read(state->regmap, offset, &val);
  65                 if (on)
  66                         val |= reset;
  67                 else
  68                         val &= ~reset;
  69                 regmap_write(state->regmap, offset, val);
  70                 if (on)
  71                         val |= EXYNOS4_MIPI_PHY_ENABLE;
  72                 else if (!(val & EXYNOS4_MIPI_PHY_RESET_MASK))
  73                         val &= ~EXYNOS4_MIPI_PHY_ENABLE;
  74                 regmap_write(state->regmap, offset, val);
  75         } else {
  76                 addr = state->regs + EXYNOS_MIPI_PHY_CONTROL(id / 2);
  77
  78                 val = readl(addr);
  79                 if (on)
  80                         val |= reset;
  81                 else
  82                         val &= ~reset;
  83                 writel(val, addr);
  84                 /* Clear ENABLE bit only if MRESETN, SRESETN bits are not set */
  85                 if (on)
  86                         val |= EXYNOS4_MIPI_PHY_ENABLE;
  87                 else if (!(val & EXYNOS4_MIPI_PHY_RESET_MASK))
  88                         val &= ~EXYNOS4_MIPI_PHY_ENABLE;
  89
  90                 writel(val, addr);
  91         }
  92
  93         spin_unlock(&state->slock);
  94         return 0;
  95 }
  96
  97 #define to_mipi_video_phy(desc) \
  98         container_of((desc), struct exynos_mipi_video_phy, phys[(desc)->index]);
  99
 100 static int exynos_mipi_video_phy_power_on(struct phy *phy)
 101 {
 102         struct video_phy_desc *phy_desc = phy_get_drvdata(phy);
 103         struct exynos_mipi_video_phy *state = to_mipi_video_phy(phy_desc);
 104
 105         return __set_phy_state(state, phy_desc->index, 1);
 106 }
 107
 108 static int exynos_mipi_video_phy_power_off(struct phy *phy)
 109 {
 110         struct video_phy_desc *phy_desc = phy_get_drvdata(phy);
 111         struct exynos_mipi_video_phy *state = to_mipi_video_phy(phy_desc);
 112
 113         return __set_phy_state(state, phy_desc->index, 0);
 114 }
 115
 116 static struct phy *exynos_mipi_video_phy_xlate(struct device *dev,
 117                                         struct of_phandle_args *args)
 118 {
 119         struct exynos_mipi_video_phy *state = dev_get_drvdata(dev);
 120
 121         if (WARN_ON(args->args[0] >= EXYNOS_MIPI_PHYS_NUM))
 122                 return ERR_PTR(-ENODEV);
 123
 124         return state->phys[args->args[0]].phy;
 125 }
 126
 127 static struct phy_ops exynos_mipi_video_phy_ops = {
 128         .power_on       = exynos_mipi_video_phy_power_on,
 129         .power_off      = exynos_mipi_video_phy_power_off,
 130         .owner          = THIS_MODULE,
 131 };
 132
 133 static int exynos_mipi_video_phy_probe(struct platform_device *pdev)
 134 {
 135         struct exynos_mipi_video_phy *state;
 136         struct device *dev = &pdev->dev;
 137         struct phy_provider *phy_provider;
 138         unsigned int i;
 139
 140         state = devm_kzalloc(dev, sizeof(*state), GFP_KERNEL);
 141         if (!state)
 142                 return -ENOMEM;
 143
 144         state->regmap = syscon_regmap_lookup_by_phandle(dev->of_node, "syscon");
 145         if (IS_ERR(state->regmap)) {
 146                 struct resource *res;
 147
 148                 dev_info(dev, "regmap lookup failed: %ld\n",
 149                          PTR_ERR(state->regmap));
 150
 151                 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 152                 state->regs = devm_ioremap_resource(dev, res);
 153                 if (IS_ERR(state->regs))
 154                         return PTR_ERR(state->regs);
 155         }
 156
 157         dev_set_drvdata(dev, state);
 158         spin_lock_init(&state->slock);
 159
 160         for (i = 0; i < EXYNOS_MIPI_PHYS_NUM; i++) {
 161                 struct phy *phy = devm_phy_create(dev, NULL,
 162                                                   &exynos_mipi_video_phy_ops);
 163                 if (IS_ERR(phy)) {
 164                         dev_err(dev, "failed to create PHY %d\n", i);
 165                         return PTR_ERR(phy);
 166                 }
 167
 168                 state->phys[i].phy = phy;
 169                 state->phys[i].index = i;
 170                 phy_set_drvdata(phy, &state->phys[i]);
 171         }
 172
 173         phy_provider = devm_of_phy_provider_register(dev,
 174                                         exynos_mipi_video_phy_xlate);
 175
 176         return PTR_ERR_OR_ZERO(phy_provider);
 177 }
 178
 179 static const struct of_device_id exynos_mipi_video_phy_of_match[] = {
 180         { .compatible = "samsung,s5pv210-mipi-video-phy" },
 181         { },
 182 };
 183 MODULE_DEVICE_TABLE(of, exynos_mipi_video_phy_of_match);
 184
 185 static struct platform_driver exynos_mipi_video_phy_driver = {
 186         .probe  = exynos_mipi_video_phy_probe,
 187         .driver = {
 188                 .of_match_table = exynos_mipi_video_phy_of_match,
 189                 .name  = "exynos-mipi-video-phy",
 190         }
 191 };
 192 module_platform_driver(exynos_mipi_video_phy_driver);
 193
 194 MODULE_DESCRIPTION("Samsung S5P/EXYNOS SoC MIPI CSI-2/DSI PHY driver");
 195 MODULE_AUTHOR("Sylwester Nawrocki <s.nawrocki@samsung.com>");
 196 MODULE_LICENSE("GPL v2");