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/io.h>
  13 #include <linux/kernel.h>
  14 #include <linux/module.h>
  15 #include <linux/of.h>
  16 #include <linux/of_address.h>
  17 #include <linux/phy/phy.h>
  18 #include <linux/platform_device.h>
  19 #include <linux/spinlock.h>
  20
  21 /* MIPI_PHYn_CONTROL register offset: n = 0..1 */
  22 #define EXYNOS_MIPI_PHY_CONTROL(n)      ((n) * 4)
  23 #define EXYNOS_MIPI_PHY_ENABLE          (1 << 0)
  24 #define EXYNOS_MIPI_PHY_SRESETN         (1 << 1)
  25 #define EXYNOS_MIPI_PHY_MRESETN         (1 << 2)
  26 #define EXYNOS_MIPI_PHY_RESET_MASK      (3 << 1)
  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         spinlock_t slock;
  41         struct video_phy_desc {
  42                 struct phy *phy;
  43                 unsigned int index;
  44         } phys[EXYNOS_MIPI_PHYS_NUM];
  45         void __iomem *regs;
  46 };
  47
  48 static int __set_phy_state(struct exynos_mipi_video_phy *state,
  49                         enum exynos_mipi_phy_id id, unsigned int on)
  50 {
  51         void __iomem *addr;
  52         u32 reg, reset;
  53
  54         addr = state->regs + EXYNOS_MIPI_PHY_CONTROL(id / 2);
  55
  56         if (is_mipi_dsim_phy_id(id))
  57                 reset = EXYNOS_MIPI_PHY_MRESETN;
  58         else
  59                 reset = EXYNOS_MIPI_PHY_SRESETN;
  60
  61         spin_lock(&state->slock);
  62         reg = readl(addr);
  63         if (on)
  64                 reg |= reset;
  65         else
  66                 reg &= ~reset;
  67         writel(reg, addr);
  68
  69         /* Clear ENABLE bit only if MRESETN, SRESETN bits are not set. */
  70         if (on)
  71                 reg |= EXYNOS_MIPI_PHY_ENABLE;
  72         else if (!(reg & EXYNOS_MIPI_PHY_RESET_MASK))
  73                 reg &= ~EXYNOS_MIPI_PHY_ENABLE;
  74
  75         writel(reg, addr);
  76         spin_unlock(&state->slock);
  77         return 0;
  78 }
  79
  80 #define to_mipi_video_phy(desc) \
  81         container_of((desc), struct exynos_mipi_video_phy, phys[(desc)->index]);
  82
  83 static int exynos_mipi_video_phy_power_on(struct phy *phy)
  84 {
  85         struct video_phy_desc *phy_desc = phy_get_drvdata(phy);
  86         struct exynos_mipi_video_phy *state = to_mipi_video_phy(phy_desc);
  87
  88         return __set_phy_state(state, phy_desc->index, 1);
  89 }
  90
  91 static int exynos_mipi_video_phy_power_off(struct phy *phy)
  92 {
  93         struct video_phy_desc *phy_desc = phy_get_drvdata(phy);
  94         struct exynos_mipi_video_phy *state = to_mipi_video_phy(phy_desc);
  95
  96         return __set_phy_state(state, phy_desc->index, 0);
  97 }
  98
  99 static struct phy *exynos_mipi_video_phy_xlate(struct device *dev,
 100                                         struct of_phandle_args *args)
 101 {
 102         struct exynos_mipi_video_phy *state = dev_get_drvdata(dev);
 103
 104         if (WARN_ON(args->args[0] > EXYNOS_MIPI_PHYS_NUM))
 105                 return ERR_PTR(-ENODEV);
 106
 107         return state->phys[args->args[0]].phy;
 108 }
 109
 110 static struct phy_ops exynos_mipi_video_phy_ops = {
 111         .power_on       = exynos_mipi_video_phy_power_on,
 112         .power_off      = exynos_mipi_video_phy_power_off,
 113         .owner          = THIS_MODULE,
 114 };
 115
 116 static int exynos_mipi_video_phy_probe(struct platform_device *pdev)
 117 {
 118         struct exynos_mipi_video_phy *state;
 119         struct device *dev = &pdev->dev;
 120         struct resource *res;
 121         struct phy_provider *phy_provider;
 122         unsigned int i;
 123
 124         state = devm_kzalloc(dev, sizeof(*state), GFP_KERNEL);
 125         if (!state)
 126                 return -ENOMEM;
 127
 128         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 129
 130         state->regs = devm_ioremap_resource(dev, res);
 131         if (IS_ERR(state->regs))
 132                 return PTR_ERR(state->regs);
 133
 134         dev_set_drvdata(dev, state);
 135         spin_lock_init(&state->slock);
 136
 137         phy_provider = devm_of_phy_provider_register(dev,
 138                                         exynos_mipi_video_phy_xlate);
 139         if (IS_ERR(phy_provider))
 140                 return PTR_ERR(phy_provider);
 141
 142         for (i = 0; i < EXYNOS_MIPI_PHYS_NUM; i++) {
 143                 struct phy *phy = devm_phy_create(dev,
 144                                         &exynos_mipi_video_phy_ops, NULL);
 145                 if (IS_ERR(phy)) {
 146                         dev_err(dev, "failed to create PHY %d\n", i);
 147                         return PTR_ERR(phy);
 148                 }
 149
 150                 state->phys[i].phy = phy;
 151                 state->phys[i].index = i;
 152                 phy_set_drvdata(phy, &state->phys[i]);
 153         }
 154
 155         return 0;
 156 }
 157
 158 static const struct of_device_id exynos_mipi_video_phy_of_match[] = {
 159         { .compatible = "samsung,s5pv210-mipi-video-phy" },
 160         { },
 161 };
 162 MODULE_DEVICE_TABLE(of, exynos_mipi_video_phy_of_match);
 163
 164 static struct platform_driver exynos_mipi_video_phy_driver = {
 165         .probe  = exynos_mipi_video_phy_probe,
 166         .driver = {
 167                 .of_match_table = exynos_mipi_video_phy_of_match,
 168                 .name  = "exynos-mipi-video-phy",
 169                 .owner = THIS_MODULE,
 170         }
 171 };
 172 module_platform_driver(exynos_mipi_video_phy_driver);
 173
 174 MODULE_DESCRIPTION("Samsung S5P/EXYNOS SoC MIPI CSI-2/DSI PHY driver");
 175 MODULE_AUTHOR("Sylwester Nawrocki <s.nawrocki@samsung.com>");
 176 MODULE_LICENSE("GPL v2");