drivers/phy/phy-samsung-usb2.c

   1 /*
   2  * Samsung SoC USB 1.1/2.0 PHY driver
   3  *
   4  * Copyright (C) 2013 Samsung Electronics Co., Ltd.
   5  * Author: Kamil Debski <k.debski@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/clk.h>
  13 #include <linux/mfd/syscon.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 #include "phy-samsung-usb2.h"
  21
  22 static int samsung_usb2_phy_power_on(struct phy *phy)
  23 {
  24         struct samsung_usb2_phy_instance *inst = phy_get_drvdata(phy);
  25         struct samsung_usb2_phy_driver *drv = inst->drv;
  26         int ret;
  27
  28         dev_dbg(drv->dev, "Request to power_on \"%s\" usb phy\n",
  29                 inst->cfg->label);
  30         ret = clk_prepare_enable(drv->clk);
  31         if (ret)
  32                 goto err_main_clk;
  33         ret = clk_prepare_enable(drv->ref_clk);
  34         if (ret)
  35                 goto err_instance_clk;
  36         if (inst->cfg->power_on) {
  37                 spin_lock(&drv->lock);
  38                 ret = inst->cfg->power_on(inst);
  39                 spin_unlock(&drv->lock);
  40         }
  41
  42         return 0;
  43
  44 err_instance_clk:
  45         clk_disable_unprepare(drv->clk);
  46 err_main_clk:
  47         return ret;
  48 }
  49
  50 static int samsung_usb2_phy_power_off(struct phy *phy)
  51 {
  52         struct samsung_usb2_phy_instance *inst = phy_get_drvdata(phy);
  53         struct samsung_usb2_phy_driver *drv = inst->drv;
  54         int ret = 0;
  55
  56         dev_dbg(drv->dev, "Request to power_off \"%s\" usb phy\n",
  57                 inst->cfg->label);
  58         if (inst->cfg->power_off) {
  59                 spin_lock(&drv->lock);
  60                 ret = inst->cfg->power_off(inst);
  61                 spin_unlock(&drv->lock);
  62         }
  63         clk_disable_unprepare(drv->ref_clk);
  64         clk_disable_unprepare(drv->clk);
  65         return ret;
  66 }
  67
  68 static struct phy_ops samsung_usb2_phy_ops = {
  69         .power_on       = samsung_usb2_phy_power_on,
  70         .power_off      = samsung_usb2_phy_power_off,
  71         .owner          = THIS_MODULE,
  72 };
  73
  74 static struct phy *samsung_usb2_phy_xlate(struct device *dev,
  75                                         struct of_phandle_args *args)
  76 {
  77         struct samsung_usb2_phy_driver *drv;
  78
  79         drv = dev_get_drvdata(dev);
  80         if (!drv)
  81                 return ERR_PTR(-EINVAL);
  82
  83         if (WARN_ON(args->args[0] >= drv->cfg->num_phys))
  84                 return ERR_PTR(-ENODEV);
  85
  86         return drv->instances[args->args[0]].phy;
  87 }
  88
  89 static const struct of_device_id samsung_usb2_phy_of_match[] = {
  90 #ifdef CONFIG_PHY_EXYNOS4210_USB2
  91         {
  92                 .compatible = "samsung,exynos4210-usb2-phy",
  93                 .data = &exynos4210_usb2_phy_config,
  94         },
  95 #endif
  96 #ifdef CONFIG_PHY_EXYNOS4X12_USB2
  97         {
  98                 .compatible = "samsung,exynos4x12-usb2-phy",
  99                 .data = &exynos4x12_usb2_phy_config,
 100         },
 101 #endif
 102 #ifdef CONFIG_PHY_EXYNOS5250_USB2
 103         {
 104                 .compatible = "samsung,exynos5250-usb2-phy",
 105                 .data = &exynos5250_usb2_phy_config,
 106         },
 107 #endif
 108         { },
 109 };
 110
 111 static int samsung_usb2_phy_probe(struct platform_device *pdev)
 112 {
 113         const struct of_device_id *match;
 114         const struct samsung_usb2_phy_config *cfg;
 115         struct device *dev = &pdev->dev;
 116         struct phy_provider *phy_provider;
 117         struct resource *mem;
 118         struct samsung_usb2_phy_driver *drv;
 119         int i, ret;
 120
 121         if (!pdev->dev.of_node) {
 122                 dev_err(dev, "This driver is required to be instantiated from device tree\n");
 123                 return -EINVAL;
 124         }
 125
 126         match = of_match_node(samsung_usb2_phy_of_match, pdev->dev.of_node);
 127         if (!match) {
 128                 dev_err(dev, "of_match_node() failed\n");
 129                 return -EINVAL;
 130         }
 131         cfg = match->data;
 132
 133         drv = devm_kzalloc(dev, sizeof(struct samsung_usb2_phy_driver) +
 134                 cfg->num_phys * sizeof(struct samsung_usb2_phy_instance),
 135                                                                 GFP_KERNEL);
 136         if (!drv)
 137                 return -ENOMEM;
 138
 139         dev_set_drvdata(dev, drv);
 140         spin_lock_init(&drv->lock);
 141
 142         drv->cfg = cfg;
 143         drv->dev = dev;
 144
 145         mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 146         drv->reg_phy = devm_ioremap_resource(dev, mem);
 147         if (IS_ERR(drv->reg_phy)) {
 148                 dev_err(dev, "Failed to map register memory (phy)\n");
 149                 return PTR_ERR(drv->reg_phy);
 150         }
 151
 152         drv->reg_pmu = syscon_regmap_lookup_by_phandle(pdev->dev.of_node,
 153                 "samsung,pmureg-phandle");
 154         if (IS_ERR(drv->reg_pmu)) {
 155                 dev_err(dev, "Failed to map PMU registers (via syscon)\n");
 156                 return PTR_ERR(drv->reg_pmu);
 157         }
 158
 159         if (drv->cfg->has_mode_switch) {
 160                 drv->reg_sys = syscon_regmap_lookup_by_phandle(
 161                                 pdev->dev.of_node, "samsung,sysreg-phandle");
 162                 if (IS_ERR(drv->reg_sys)) {
 163                         dev_err(dev, "Failed to map system registers (via syscon)\n");
 164                         return PTR_ERR(drv->reg_sys);
 165                 }
 166         }
 167
 168         drv->clk = devm_clk_get(dev, "phy");
 169         if (IS_ERR(drv->clk)) {
 170                 dev_err(dev, "Failed to get clock of phy controller\n");
 171                 return PTR_ERR(drv->clk);
 172         }
 173
 174         drv->ref_clk = devm_clk_get(dev, "ref");
 175         if (IS_ERR(drv->ref_clk)) {
 176                 dev_err(dev, "Failed to get reference clock for the phy controller\n");
 177                 return PTR_ERR(drv->ref_clk);
 178         }
 179
 180         drv->ref_rate = clk_get_rate(drv->ref_clk);
 181         if (drv->cfg->rate_to_clk) {
 182                 ret = drv->cfg->rate_to_clk(drv->ref_rate, &drv->ref_reg_val);
 183                 if (ret)
 184                         return ret;
 185         }
 186
 187         for (i = 0; i < drv->cfg->num_phys; i++) {
 188                 char *label = drv->cfg->phys[i].label;
 189                 struct samsung_usb2_phy_instance *p = &drv->instances[i];
 190
 191                 dev_dbg(dev, "Creating phy \"%s\"\n", label);
 192                 p->phy = devm_phy_create(dev, &samsung_usb2_phy_ops, NULL);
 193                 if (IS_ERR(p->phy)) {
 194                         dev_err(drv->dev, "Failed to create usb2_phy \"%s\"\n",
 195                                 label);
 196                         return PTR_ERR(p->phy);
 197                 }
 198
 199                 p->cfg = &drv->cfg->phys[i];
 200                 p->drv = drv;
 201                 phy_set_bus_width(p->phy, 8);
 202                 phy_set_drvdata(p->phy, p);
 203         }
 204
 205         phy_provider = devm_of_phy_provider_register(dev,
 206                                                         samsung_usb2_phy_xlate);
 207         if (IS_ERR(phy_provider)) {
 208                 dev_err(drv->dev, "Failed to register phy provider\n");
 209                 return PTR_ERR(phy_provider);
 210         }
 211
 212         return 0;
 213 }
 214
 215 static struct platform_driver samsung_usb2_phy_driver = {
 216         .probe  = samsung_usb2_phy_probe,
 217         .driver = {
 218                 .of_match_table = samsung_usb2_phy_of_match,
 219                 .name           = "samsung-usb2-phy",
 220                 .owner          = THIS_MODULE,
 221         }
 222 };
 223
 224 module_platform_driver(samsung_usb2_phy_driver);
 225 MODULE_DESCRIPTION("Samsung S5P/EXYNOS SoC USB PHY driver");
 226 MODULE_AUTHOR("Kamil Debski <k.debski@samsung.com>");
 227 MODULE_LICENSE("GPL v2");
 228 MODULE_ALIAS("platform:samsung-usb2-phy");