drivers/usb/phy/phy-omap-usb3.c

   1 /*
   2  * omap-usb3 - USB PHY, talking to dwc3 controller in OMAP.
   3  *
   4  * Copyright (C) 2013 Texas Instruments Incorporated - http://www.ti.com
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * Author: Kishon Vijay Abraham I <kishon@ti.com>
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU General Public License for more details.
  16  *
  17  */
  18
  19 #include <linux/module.h>
  20 #include <linux/platform_device.h>
  21 #include <linux/slab.h>
  22 #include <linux/usb/omap_usb.h>
  23 #include <linux/of.h>
  24 #include <linux/clk.h>
  25 #include <linux/err.h>
  26 #include <linux/pm_runtime.h>
  27 #include <linux/delay.h>
  28 #include <linux/usb/omap_control_usb.h>
  29
  30 #define NUM_SYS_CLKS            5
  31 #define PLL_STATUS              0x00000004
  32 #define PLL_GO                  0x00000008
  33 #define PLL_CONFIGURATION1      0x0000000C
  34 #define PLL_CONFIGURATION2      0x00000010
  35 #define PLL_CONFIGURATION3      0x00000014
  36 #define PLL_CONFIGURATION4      0x00000020
  37
  38 #define PLL_REGM_MASK           0x001FFE00
  39 #define PLL_REGM_SHIFT          0x9
  40 #define PLL_REGM_F_MASK         0x0003FFFF
  41 #define PLL_REGM_F_SHIFT        0x0
  42 #define PLL_REGN_MASK           0x000001FE
  43 #define PLL_REGN_SHIFT          0x1
  44 #define PLL_SELFREQDCO_MASK     0x0000000E
  45 #define PLL_SELFREQDCO_SHIFT    0x1
  46 #define PLL_SD_MASK             0x0003FC00
  47 #define PLL_SD_SHIFT            0x9
  48 #define SET_PLL_GO              0x1
  49 #define PLL_TICOPWDN            0x10000
  50 #define PLL_LOCK                0x2
  51 #define PLL_IDLE                0x1
  52
  53 /*
  54  * This is an Empirical value that works, need to confirm the actual
  55  * value required for the USB3PHY_PLL_CONFIGURATION2.PLL_IDLE status
  56  * to be correctly reflected in the USB3PHY_PLL_STATUS register.
  57  */
  58 # define PLL_IDLE_TIME  100;
  59
  60 enum sys_clk_rate {
  61         CLK_RATE_UNDEFINED = -1,
  62         CLK_RATE_12MHZ,
  63         CLK_RATE_16MHZ,
  64         CLK_RATE_19MHZ,
  65         CLK_RATE_26MHZ,
  66         CLK_RATE_38MHZ
  67 };
  68
  69 static struct usb_dpll_params omap_usb3_dpll_params[NUM_SYS_CLKS] = {
  70         {1250, 5, 4, 20, 0},            /* 12 MHz */
  71         {3125, 20, 4, 20, 0},           /* 16.8 MHz */
  72         {1172, 8, 4, 20, 65537},        /* 19.2 MHz */
  73         {1250, 12, 4, 20, 0},           /* 26 MHz */
  74         {3125, 47, 4, 20, 92843},       /* 38.4 MHz */
  75 };
  76
  77 static int omap_usb3_suspend(struct usb_phy *x, int suspend)
  78 {
  79         struct omap_usb *phy = phy_to_omapusb(x);
  80         int     val;
  81         int timeout = PLL_IDLE_TIME;
  82
  83         if (suspend && !phy->is_suspended) {
  84                 val = omap_usb_readl(phy->pll_ctrl_base, PLL_CONFIGURATION2);
  85                 val |= PLL_IDLE;
  86                 omap_usb_writel(phy->pll_ctrl_base, PLL_CONFIGURATION2, val);
  87
  88                 do {
  89                         val = omap_usb_readl(phy->pll_ctrl_base, PLL_STATUS);
  90                         if (val & PLL_TICOPWDN)
  91                                 break;
  92                         udelay(1);
  93                 } while (--timeout);
  94
  95                 omap_control_usb3_phy_power(phy->control_dev, 0);
  96
  97                 phy->is_suspended       = 1;
  98         } else if (!suspend && phy->is_suspended) {
  99                 phy->is_suspended       = 0;
 100
 101                 val = omap_usb_readl(phy->pll_ctrl_base, PLL_CONFIGURATION2);
 102                 val &= ~PLL_IDLE;
 103                 omap_usb_writel(phy->pll_ctrl_base, PLL_CONFIGURATION2, val);
 104
 105                 do {
 106                         val = omap_usb_readl(phy->pll_ctrl_base, PLL_STATUS);
 107                         if (!(val & PLL_TICOPWDN))
 108                                 break;
 109                         udelay(1);
 110                 } while (--timeout);
 111         }
 112
 113         return 0;
 114 }
 115
 116 static inline enum sys_clk_rate __get_sys_clk_index(unsigned long rate)
 117 {
 118         switch (rate) {
 119         case 12000000:
 120                 return CLK_RATE_12MHZ;
 121         case 16800000:
 122                 return CLK_RATE_16MHZ;
 123         case 19200000:
 124                 return CLK_RATE_19MHZ;
 125         case 26000000:
 126                 return CLK_RATE_26MHZ;
 127         case 38400000:
 128                 return CLK_RATE_38MHZ;
 129         default:
 130                 return CLK_RATE_UNDEFINED;
 131         }
 132 }
 133
 134 static void omap_usb_dpll_relock(struct omap_usb *phy)
 135 {
 136         u32             val;
 137         unsigned long   timeout;
 138
 139         omap_usb_writel(phy->pll_ctrl_base, PLL_GO, SET_PLL_GO);
 140
 141         timeout = jiffies + msecs_to_jiffies(20);
 142         do {
 143                 val = omap_usb_readl(phy->pll_ctrl_base, PLL_STATUS);
 144                 if (val & PLL_LOCK)
 145                         break;
 146         } while (!WARN_ON(time_after(jiffies, timeout)));
 147 }
 148
 149 static int omap_usb_dpll_lock(struct omap_usb *phy)
 150 {
 151         u32                     val;
 152         unsigned long           rate;
 153         enum sys_clk_rate       clk_index;
 154
 155         rate            = clk_get_rate(phy->sys_clk);
 156         clk_index       = __get_sys_clk_index(rate);
 157
 158         if (clk_index == CLK_RATE_UNDEFINED) {
 159                 pr_err("dpll cannot be locked for sys clk freq:%luHz\n", rate);
 160                 return -EINVAL;
 161         }
 162
 163         val = omap_usb_readl(phy->pll_ctrl_base, PLL_CONFIGURATION1);
 164         val &= ~PLL_REGN_MASK;
 165         val |= omap_usb3_dpll_params[clk_index].n << PLL_REGN_SHIFT;
 166         omap_usb_writel(phy->pll_ctrl_base, PLL_CONFIGURATION1, val);
 167
 168         val = omap_usb_readl(phy->pll_ctrl_base, PLL_CONFIGURATION2);
 169         val &= ~PLL_SELFREQDCO_MASK;
 170         val |= omap_usb3_dpll_params[clk_index].freq << PLL_SELFREQDCO_SHIFT;
 171         omap_usb_writel(phy->pll_ctrl_base, PLL_CONFIGURATION2, val);
 172
 173         val = omap_usb_readl(phy->pll_ctrl_base, PLL_CONFIGURATION1);
 174         val &= ~PLL_REGM_MASK;
 175         val |= omap_usb3_dpll_params[clk_index].m << PLL_REGM_SHIFT;
 176         omap_usb_writel(phy->pll_ctrl_base, PLL_CONFIGURATION1, val);
 177
 178         val = omap_usb_readl(phy->pll_ctrl_base, PLL_CONFIGURATION4);
 179         val &= ~PLL_REGM_F_MASK;
 180         val |= omap_usb3_dpll_params[clk_index].mf << PLL_REGM_F_SHIFT;
 181         omap_usb_writel(phy->pll_ctrl_base, PLL_CONFIGURATION4, val);
 182
 183         val = omap_usb_readl(phy->pll_ctrl_base, PLL_CONFIGURATION3);
 184         val &= ~PLL_SD_MASK;
 185         val |= omap_usb3_dpll_params[clk_index].sd << PLL_SD_SHIFT;
 186         omap_usb_writel(phy->pll_ctrl_base, PLL_CONFIGURATION3, val);
 187
 188         omap_usb_dpll_relock(phy);
 189
 190         return 0;
 191 }
 192
 193 static int omap_usb3_init(struct usb_phy *x)
 194 {
 195         struct omap_usb *phy = phy_to_omapusb(x);
 196
 197         omap_usb_dpll_lock(phy);
 198         omap_control_usb3_phy_power(phy->control_dev, 1);
 199
 200         return 0;
 201 }
 202
 203 static int omap_usb3_probe(struct platform_device *pdev)
 204 {
 205         struct omap_usb                 *phy;
 206         struct resource                 *res;
 207
 208         phy = devm_kzalloc(&pdev->dev, sizeof(*phy), GFP_KERNEL);
 209         if (!phy) {
 210                 dev_err(&pdev->dev, "unable to alloc mem for OMAP USB3 PHY\n");
 211                 return -ENOMEM;
 212         }
 213
 214         res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "pll_ctrl");
 215         phy->pll_ctrl_base = devm_ioremap_resource(&pdev->dev, res);
 216         if (IS_ERR(phy->pll_ctrl_base))
 217                 return PTR_ERR(phy->pll_ctrl_base);
 218
 219         phy->dev                = &pdev->dev;
 220
 221         phy->phy.dev            = phy->dev;
 222         phy->phy.label          = "omap-usb3";
 223         phy->phy.init           = omap_usb3_init;
 224         phy->phy.set_suspend    = omap_usb3_suspend;
 225         phy->phy.type           = USB_PHY_TYPE_USB3;
 226
 227         phy->is_suspended       = 1;
 228         phy->wkupclk = devm_clk_get(phy->dev, "usb_phy_cm_clk32k");
 229         if (IS_ERR(phy->wkupclk)) {
 230                 dev_err(&pdev->dev, "unable to get usb_phy_cm_clk32k\n");
 231                 return PTR_ERR(phy->wkupclk);
 232         }
 233         clk_prepare(phy->wkupclk);
 234
 235         phy->optclk = devm_clk_get(phy->dev, "usb_otg_ss_refclk960m");
 236         if (IS_ERR(phy->optclk)) {
 237                 dev_err(&pdev->dev, "unable to get usb_otg_ss_refclk960m\n");
 238                 return PTR_ERR(phy->optclk);
 239         }
 240         clk_prepare(phy->optclk);
 241
 242         phy->sys_clk = devm_clk_get(phy->dev, "sys_clkin");
 243         if (IS_ERR(phy->sys_clk)) {
 244                 pr_err("%s: unable to get sys_clkin\n", __func__);
 245                 return -EINVAL;
 246         }
 247
 248         phy->control_dev = omap_get_control_dev();
 249         if (IS_ERR(phy->control_dev)) {
 250                 dev_dbg(&pdev->dev, "Failed to get control device\n");
 251                 return -ENODEV;
 252         }
 253
 254         omap_control_usb3_phy_power(phy->control_dev, 0);
 255         usb_add_phy_dev(&phy->phy);
 256
 257         platform_set_drvdata(pdev, phy);
 258
 259         pm_runtime_enable(phy->dev);
 260         pm_runtime_get(&pdev->dev);
 261
 262         return 0;
 263 }
 264
 265 static int omap_usb3_remove(struct platform_device *pdev)
 266 {
 267         struct omap_usb *phy = platform_get_drvdata(pdev);
 268
 269         clk_unprepare(phy->wkupclk);
 270         clk_unprepare(phy->optclk);
 271         usb_remove_phy(&phy->phy);
 272         if (!pm_runtime_suspended(&pdev->dev))
 273                 pm_runtime_put(&pdev->dev);
 274         pm_runtime_disable(&pdev->dev);
 275
 276         return 0;
 277 }
 278
 279 #ifdef CONFIG_PM_RUNTIME
 280
 281 static int omap_usb3_runtime_suspend(struct device *dev)
 282 {
 283         struct platform_device  *pdev = to_platform_device(dev);
 284         struct omap_usb *phy = platform_get_drvdata(pdev);
 285
 286         clk_disable(phy->wkupclk);
 287         clk_disable(phy->optclk);
 288
 289         return 0;
 290 }
 291
 292 static int omap_usb3_runtime_resume(struct device *dev)
 293 {
 294         u32 ret = 0;
 295         struct platform_device  *pdev = to_platform_device(dev);
 296         struct omap_usb *phy = platform_get_drvdata(pdev);
 297
 298         ret = clk_enable(phy->optclk);
 299         if (ret) {
 300                 dev_err(phy->dev, "Failed to enable optclk %d\n", ret);
 301                 goto err1;
 302         }
 303
 304         ret = clk_enable(phy->wkupclk);
 305         if (ret) {
 306                 dev_err(phy->dev, "Failed to enable wkupclk %d\n", ret);
 307                 goto err2;
 308         }
 309
 310         return 0;
 311
 312 err2:
 313         clk_disable(phy->optclk);
 314
 315 err1:
 316         return ret;
 317 }
 318
 319 static const struct dev_pm_ops omap_usb3_pm_ops = {
 320         SET_RUNTIME_PM_OPS(omap_usb3_runtime_suspend, omap_usb3_runtime_resume,
 321                 NULL)
 322 };
 323
 324 #define DEV_PM_OPS     (&omap_usb3_pm_ops)
 325 #else
 326 #define DEV_PM_OPS     NULL
 327 #endif
 328
 329 #ifdef CONFIG_OF
 330 static const struct of_device_id omap_usb3_id_table[] = {
 331         { .compatible = "ti,omap-usb3" },
 332         {}
 333 };
 334 MODULE_DEVICE_TABLE(of, omap_usb3_id_table);
 335 #endif
 336
 337 static struct platform_driver omap_usb3_driver = {
 338         .probe          = omap_usb3_probe,
 339         .remove         = omap_usb3_remove,
 340         .driver         = {
 341                 .name   = "omap-usb3",
 342                 .owner  = THIS_MODULE,
 343                 .pm     = DEV_PM_OPS,
 344                 .of_match_table = of_match_ptr(omap_usb3_id_table),
 345         },
 346 };
 347
 348 module_platform_driver(omap_usb3_driver);
 349
 350 MODULE_ALIAS("platform: omap_usb3");
 351 MODULE_AUTHOR("Texas Instruments Inc.");
 352 MODULE_DESCRIPTION("OMAP USB3 phy driver");
 353 MODULE_LICENSE("GPL v2");