drivers/usb/phy/samsung-usbphy.c

   1 /* linux/drivers/usb/phy/samsung-usbphy.c
   2  *
   3  * Copyright (c) 2012 Samsung Electronics Co., Ltd.
   4  *              http://www.samsung.com
   5  *
   6  * Author: Praveen Paneri <p.paneri@samsung.com>
   7  *
   8  * Samsung USB2.0 High-speed OTG transceiver, talks to S3C HS OTG controller
   9  *
  10  * This program is free software; you can redistribute it and/or modify
  11  * it under the terms of the GNU General Public License version 2 as
  12  * published by the Free Software Foundation.
  13  *
  14  * This program is distributed in the hope that it will be useful,
  15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17  * GNU General Public License for more details.
  18  */
  19
  20 #include <linux/module.h>
  21 #include <linux/platform_device.h>
  22 #include <linux/clk.h>
  23 #include <linux/delay.h>
  24 #include <linux/err.h>
  25 #include <linux/io.h>
  26 #include <linux/of.h>
  27 #include <linux/usb/otg.h>
  28 #include <linux/platform_data/samsung-usbphy.h>
  29
  30 /* Register definitions */
  31
  32 #define SAMSUNG_PHYPWR                          (0x00)
  33
  34 #define PHYPWR_NORMAL_MASK                      (0x19 << 0)
  35 #define PHYPWR_OTG_DISABLE                      (0x1 << 4)
  36 #define PHYPWR_ANALOG_POWERDOWN                 (0x1 << 3)
  37 #define PHYPWR_FORCE_SUSPEND                    (0x1 << 1)
  38 /* For Exynos4 */
  39 #define PHYPWR_NORMAL_MASK_PHY0                 (0x39 << 0)
  40 #define PHYPWR_SLEEP_PHY0                       (0x1 << 5)
  41
  42 #define SAMSUNG_PHYCLK                          (0x04)
  43
  44 #define PHYCLK_MODE_USB11                       (0x1 << 6)
  45 #define PHYCLK_EXT_OSC                          (0x1 << 5)
  46 #define PHYCLK_COMMON_ON_N                      (0x1 << 4)
  47 #define PHYCLK_ID_PULL                          (0x1 << 2)
  48 #define PHYCLK_CLKSEL_MASK                      (0x3 << 0)
  49 #define PHYCLK_CLKSEL_48M                       (0x0 << 0)
  50 #define PHYCLK_CLKSEL_12M                       (0x2 << 0)
  51 #define PHYCLK_CLKSEL_24M                       (0x3 << 0)
  52
  53 #define SAMSUNG_RSTCON                          (0x08)
  54
  55 #define RSTCON_PHYLINK_SWRST                    (0x1 << 2)
  56 #define RSTCON_HLINK_SWRST                      (0x1 << 1)
  57 #define RSTCON_SWRST                            (0x1 << 0)
  58
  59 #ifndef MHZ
  60 #define MHZ (1000*1000)
  61 #endif
  62
  63 enum samsung_cpu_type {
  64         TYPE_S3C64XX,
  65         TYPE_EXYNOS4210,
  66 };
  67
  68 /*
  69  * struct samsung_usbphy - transceiver driver state
  70  * @phy: transceiver structure
  71  * @plat: platform data
  72  * @dev: The parent device supplied to the probe function
  73  * @clk: usb phy clock
  74  * @regs: usb phy register memory base
  75  * @ref_clk_freq: reference clock frequency selection
  76  * @cpu_type: machine identifier
  77  */
  78 struct samsung_usbphy {
  79         struct usb_phy  phy;
  80         struct samsung_usbphy_data *plat;
  81         struct device   *dev;
  82         struct clk      *clk;
  83         void __iomem    *regs;
  84         int             ref_clk_freq;
  85         int             cpu_type;
  86 };
  87
  88 #define phy_to_sphy(x)          container_of((x), struct samsung_usbphy, phy)
  89
  90 /*
  91  * Returns reference clock frequency selection value
  92  */
  93 static int samsung_usbphy_get_refclk_freq(struct samsung_usbphy *sphy)
  94 {
  95         struct clk *ref_clk;
  96         int refclk_freq = 0;
  97
  98         ref_clk = clk_get(sphy->dev, "xusbxti");
  99         if (IS_ERR(ref_clk)) {
 100                 dev_err(sphy->dev, "Failed to get reference clock\n");
 101                 return PTR_ERR(ref_clk);
 102         }
 103
 104         switch (clk_get_rate(ref_clk)) {
 105         case 12 * MHZ:
 106                 refclk_freq = PHYCLK_CLKSEL_12M;
 107                 break;
 108         case 24 * MHZ:
 109                 refclk_freq = PHYCLK_CLKSEL_24M;
 110                 break;
 111         case 48 * MHZ:
 112                 refclk_freq = PHYCLK_CLKSEL_48M;
 113                 break;
 114         default:
 115                 if (sphy->cpu_type == TYPE_S3C64XX)
 116                         refclk_freq = PHYCLK_CLKSEL_48M;
 117                 else
 118                         refclk_freq = PHYCLK_CLKSEL_24M;
 119                 break;
 120         }
 121         clk_put(ref_clk);
 122
 123         return refclk_freq;
 124 }
 125
 126 static void samsung_usbphy_enable(struct samsung_usbphy *sphy)
 127 {
 128         void __iomem *regs = sphy->regs;
 129         u32 phypwr;
 130         u32 phyclk;
 131         u32 rstcon;
 132
 133         /* set clock frequency for PLL */
 134         phyclk = sphy->ref_clk_freq;
 135         phypwr = readl(regs + SAMSUNG_PHYPWR);
 136         rstcon = readl(regs + SAMSUNG_RSTCON);
 137
 138         switch (sphy->cpu_type) {
 139         case TYPE_S3C64XX:
 140                 phyclk &= ~PHYCLK_COMMON_ON_N;
 141                 phypwr &= ~PHYPWR_NORMAL_MASK;
 142                 rstcon |= RSTCON_SWRST;
 143                 break;
 144         case TYPE_EXYNOS4210:
 145                 phypwr &= ~PHYPWR_NORMAL_MASK_PHY0;
 146                 rstcon |= RSTCON_SWRST;
 147         default:
 148                 break;
 149         }
 150
 151         writel(phyclk, regs + SAMSUNG_PHYCLK);
 152         /* Configure PHY0 for normal operation*/
 153         writel(phypwr, regs + SAMSUNG_PHYPWR);
 154         /* reset all ports of PHY and Link */
 155         writel(rstcon, regs + SAMSUNG_RSTCON);
 156         udelay(10);
 157         rstcon &= ~RSTCON_SWRST;
 158         writel(rstcon, regs + SAMSUNG_RSTCON);
 159 }
 160
 161 static void samsung_usbphy_disable(struct samsung_usbphy *sphy)
 162 {
 163         void __iomem *regs = sphy->regs;
 164         u32 phypwr;
 165
 166         phypwr = readl(regs + SAMSUNG_PHYPWR);
 167
 168         switch (sphy->cpu_type) {
 169         case TYPE_S3C64XX:
 170                 phypwr |= PHYPWR_NORMAL_MASK;
 171                 break;
 172         case TYPE_EXYNOS4210:
 173                 phypwr |= PHYPWR_NORMAL_MASK_PHY0;
 174         default:
 175                 break;
 176         }
 177
 178         /* Disable analog and otg block power */
 179         writel(phypwr, regs + SAMSUNG_PHYPWR);
 180 }
 181
 182 /*
 183  * The function passed to the usb driver for phy initialization
 184  */
 185 static int samsung_usbphy_init(struct usb_phy *phy)
 186 {
 187         struct samsung_usbphy *sphy;
 188         int ret = 0;
 189
 190         sphy = phy_to_sphy(phy);
 191
 192         /* Enable the phy clock */
 193         ret = clk_prepare_enable(sphy->clk);
 194         if (ret) {
 195                 dev_err(sphy->dev, "%s: clk_prepare_enable failed\n", __func__);
 196                 return ret;
 197         }
 198
 199         /* Disable phy isolation */
 200         if (sphy->plat && sphy->plat->pmu_isolation)
 201                 sphy->plat->pmu_isolation(false);
 202
 203         /* Initialize usb phy registers */
 204         samsung_usbphy_enable(sphy);
 205
 206         /* Disable the phy clock */
 207         clk_disable_unprepare(sphy->clk);
 208         return ret;
 209 }
 210
 211 /*
 212  * The function passed to the usb driver for phy shutdown
 213  */
 214 static void samsung_usbphy_shutdown(struct usb_phy *phy)
 215 {
 216         struct samsung_usbphy *sphy;
 217
 218         sphy = phy_to_sphy(phy);
 219
 220         if (clk_prepare_enable(sphy->clk)) {
 221                 dev_err(sphy->dev, "%s: clk_prepare_enable failed\n", __func__);
 222                 return;
 223         }
 224
 225         /* De-initialize usb phy registers */
 226         samsung_usbphy_disable(sphy);
 227
 228         /* Enable phy isolation */
 229         if (sphy->plat && sphy->plat->pmu_isolation)
 230                 sphy->plat->pmu_isolation(true);
 231
 232         clk_disable_unprepare(sphy->clk);
 233 }
 234
 235 static const struct of_device_id samsung_usbphy_dt_match[];
 236
 237 static inline int samsung_usbphy_get_driver_data(struct platform_device *pdev)
 238 {
 239         if (pdev->dev.of_node) {
 240                 const struct of_device_id *match;
 241                 match = of_match_node(samsung_usbphy_dt_match,
 242                                                         pdev->dev.of_node);
 243                 return (int) match->data;
 244         }
 245
 246         return platform_get_device_id(pdev)->driver_data;
 247 }
 248
 249 static int __devinit samsung_usbphy_probe(struct platform_device *pdev)
 250 {
 251         struct samsung_usbphy *sphy;
 252         struct samsung_usbphy_data *pdata;
 253         struct device *dev = &pdev->dev;
 254         struct resource *phy_mem;
 255         void __iomem    *phy_base;
 256         struct clk *clk;
 257
 258         pdata = pdev->dev.platform_data;
 259         if (!pdata) {
 260                 dev_err(&pdev->dev, "%s: no platform data defined\n", __func__);
 261                 return -EINVAL;
 262         }
 263
 264         phy_mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 265         if (!phy_mem) {
 266                 dev_err(dev, "%s: missing mem resource\n", __func__);
 267                 return -ENODEV;
 268         }
 269
 270         phy_base = devm_request_and_ioremap(dev, phy_mem);
 271         if (!phy_base) {
 272                 dev_err(dev, "%s: register mapping failed\n", __func__);
 273                 return -ENXIO;
 274         }
 275
 276         sphy = devm_kzalloc(dev, sizeof(*sphy), GFP_KERNEL);
 277         if (!sphy)
 278                 return -ENOMEM;
 279
 280         clk = devm_clk_get(dev, "otg");
 281         if (IS_ERR(clk)) {
 282                 dev_err(dev, "Failed to get otg clock\n");
 283                 return PTR_ERR(clk);
 284         }
 285
 286         sphy->dev               = &pdev->dev;
 287         sphy->plat              = pdata;
 288         sphy->regs              = phy_base;
 289         sphy->clk               = clk;
 290         sphy->phy.dev           = sphy->dev;
 291         sphy->phy.label         = "samsung-usbphy";
 292         sphy->phy.init          = samsung_usbphy_init;
 293         sphy->phy.shutdown      = samsung_usbphy_shutdown;
 294         sphy->cpu_type          = samsung_usbphy_get_driver_data(pdev);
 295         sphy->ref_clk_freq      = samsung_usbphy_get_refclk_freq(sphy);
 296
 297         platform_set_drvdata(pdev, sphy);
 298
 299         return usb_add_phy(&sphy->phy, USB_PHY_TYPE_USB2);
 300 }
 301
 302 static int __exit samsung_usbphy_remove(struct platform_device *pdev)
 303 {
 304         struct samsung_usbphy *sphy = platform_get_drvdata(pdev);
 305
 306         usb_remove_phy(&sphy->phy);
 307
 308         return 0;
 309 }
 310
 311 #ifdef CONFIG_OF
 312 static const struct of_device_id samsung_usbphy_dt_match[] = {
 313         {
 314                 .compatible = "samsung,s3c64xx-usbphy",
 315                 .data = (void *)TYPE_S3C64XX,
 316         }, {
 317                 .compatible = "samsung,exynos4210-usbphy",
 318                 .data = (void *)TYPE_EXYNOS4210,
 319         },
 320         {},
 321 };
 322 MODULE_DEVICE_TABLE(of, samsung_usbphy_dt_match);
 323 #endif
 324
 325 static struct platform_device_id samsung_usbphy_driver_ids[] = {
 326         {
 327                 .name           = "s3c64xx-usbphy",
 328                 .driver_data    = TYPE_S3C64XX,
 329         }, {
 330                 .name           = "exynos4210-usbphy",
 331                 .driver_data    = TYPE_EXYNOS4210,
 332         },
 333         {},
 334 };
 335
 336 MODULE_DEVICE_TABLE(platform, samsung_usbphy_driver_ids);
 337
 338 static struct platform_driver samsung_usbphy_driver = {
 339         .probe          = samsung_usbphy_probe,
 340         .remove         = __devexit_p(samsung_usbphy_remove),
 341         .id_table       = samsung_usbphy_driver_ids,
 342         .driver         = {
 343                 .name   = "samsung-usbphy",
 344                 .owner  = THIS_MODULE,
 345                 .of_match_table = of_match_ptr(samsung_usbphy_dt_match),
 346         },
 347 };
 348
 349 module_platform_driver(samsung_usbphy_driver);
 350
 351 MODULE_DESCRIPTION("Samsung USB phy controller");
 352 MODULE_AUTHOR("Praveen Paneri <p.paneri@samsung.com>");
 353 MODULE_LICENSE("GPL");
 354 MODULE_ALIAS("platform:samsung-usbphy");