drivers/usb/phy/omap-usb2.c

   1 /*
   2  * omap-usb2.c - USB PHY, talking to musb controller in OMAP.
   3  *
   4  * Copyright (C) 2012 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/of.h>
  23 #include <linux/io.h>
  24 #include <linux/usb/omap_usb.h>
  25 #include <linux/usb/phy_companion.h>
  26 #include <linux/clk.h>
  27 #include <linux/err.h>
  28 #include <linux/pm_runtime.h>
  29 #include <linux/delay.h>
  30 #include <linux/usb/omap_control_usb.h>
  31
  32 /**
  33  * omap_usb2_set_comparator - links the comparator present in the sytem with
  34  *      this phy
  35  * @comparator - the companion phy(comparator) for this phy
  36  *
  37  * The phy companion driver should call this API passing the phy_companion
  38  * filled with set_vbus and start_srp to be used by usb phy.
  39  *
  40  * For use by phy companion driver
  41  */
  42 int omap_usb2_set_comparator(struct phy_companion *comparator)
  43 {
  44         struct omap_usb *phy;
  45         struct usb_phy  *x = usb_get_phy(USB_PHY_TYPE_USB2);
  46
  47         if (IS_ERR(x))
  48                 return -ENODEV;
  49
  50         phy = phy_to_omapusb(x);
  51         phy->comparator = comparator;
  52         return 0;
  53 }
  54 EXPORT_SYMBOL_GPL(omap_usb2_set_comparator);
  55
  56 static int omap_usb_set_vbus(struct usb_otg *otg, bool enabled)
  57 {
  58         struct omap_usb *phy = phy_to_omapusb(otg->phy);
  59
  60         if (!phy->comparator)
  61                 return -ENODEV;
  62
  63         return phy->comparator->set_vbus(phy->comparator, enabled);
  64 }
  65
  66 static int omap_usb_start_srp(struct usb_otg *otg)
  67 {
  68         struct omap_usb *phy = phy_to_omapusb(otg->phy);
  69
  70         if (!phy->comparator)
  71                 return -ENODEV;
  72
  73         return phy->comparator->start_srp(phy->comparator);
  74 }
  75
  76 static int omap_usb_set_host(struct usb_otg *otg, struct usb_bus *host)
  77 {
  78         struct usb_phy  *phy = otg->phy;
  79
  80         otg->host = host;
  81         if (!host)
  82                 phy->state = OTG_STATE_UNDEFINED;
  83
  84         return 0;
  85 }
  86
  87 static int omap_usb_set_peripheral(struct usb_otg *otg,
  88                 struct usb_gadget *gadget)
  89 {
  90         struct usb_phy  *phy = otg->phy;
  91
  92         otg->gadget = gadget;
  93         if (!gadget)
  94                 phy->state = OTG_STATE_UNDEFINED;
  95
  96         return 0;
  97 }
  98
  99 static int omap_usb2_suspend(struct usb_phy *x, int suspend)
 100 {
 101         u32 ret;
 102         struct omap_usb *phy = phy_to_omapusb(x);
 103
 104         if (suspend && !phy->is_suspended) {
 105                 omap_control_usb_phy_power(phy->control_dev, 0);
 106                 pm_runtime_put_sync(phy->dev);
 107                 phy->is_suspended = 1;
 108         } else if (!suspend && phy->is_suspended) {
 109                 ret = pm_runtime_get_sync(phy->dev);
 110                 if (ret < 0) {
 111                         dev_err(phy->dev, "get_sync failed with err %d\n",
 112                                                                         ret);
 113                         return ret;
 114                 }
 115                 omap_control_usb_phy_power(phy->control_dev, 1);
 116                 phy->is_suspended = 0;
 117         }
 118
 119         return 0;
 120 }
 121
 122 static int omap_usb2_probe(struct platform_device *pdev)
 123 {
 124         struct omap_usb                 *phy;
 125         struct usb_otg                  *otg;
 126
 127         phy = devm_kzalloc(&pdev->dev, sizeof(*phy), GFP_KERNEL);
 128         if (!phy) {
 129                 dev_err(&pdev->dev, "unable to allocate memory for USB2 PHY\n");
 130                 return -ENOMEM;
 131         }
 132
 133         otg = devm_kzalloc(&pdev->dev, sizeof(*otg), GFP_KERNEL);
 134         if (!otg) {
 135                 dev_err(&pdev->dev, "unable to allocate memory for USB OTG\n");
 136                 return -ENOMEM;
 137         }
 138
 139         phy->dev                = &pdev->dev;
 140
 141         phy->phy.dev            = phy->dev;
 142         phy->phy.label          = "omap-usb2";
 143         phy->phy.set_suspend    = omap_usb2_suspend;
 144         phy->phy.otg            = otg;
 145
 146         phy->control_dev = omap_get_control_dev();
 147         if (IS_ERR(phy->control_dev)) {
 148                 dev_dbg(&pdev->dev, "Failed to get control device\n");
 149                 return -ENODEV;
 150         }
 151
 152         phy->is_suspended       = 1;
 153         omap_control_usb_phy_power(phy->control_dev, 0);
 154
 155         otg->set_host           = omap_usb_set_host;
 156         otg->set_peripheral     = omap_usb_set_peripheral;
 157         otg->set_vbus           = omap_usb_set_vbus;
 158         otg->start_srp          = omap_usb_start_srp;
 159         otg->phy                = &phy->phy;
 160
 161         phy->wkupclk = devm_clk_get(phy->dev, "usb_phy_cm_clk32k");
 162         if (IS_ERR(phy->wkupclk)) {
 163                 dev_err(&pdev->dev, "unable to get usb_phy_cm_clk32k\n");
 164                 return PTR_ERR(phy->wkupclk);
 165         }
 166         clk_prepare(phy->wkupclk);
 167
 168         usb_add_phy(&phy->phy, USB_PHY_TYPE_USB2);
 169
 170         platform_set_drvdata(pdev, phy);
 171
 172         pm_runtime_enable(phy->dev);
 173
 174         return 0;
 175 }
 176
 177 static int omap_usb2_remove(struct platform_device *pdev)
 178 {
 179         struct omap_usb *phy = platform_get_drvdata(pdev);
 180
 181         clk_unprepare(phy->wkupclk);
 182         usb_remove_phy(&phy->phy);
 183
 184         return 0;
 185 }
 186
 187 #ifdef CONFIG_PM_RUNTIME
 188
 189 static int omap_usb2_runtime_suspend(struct device *dev)
 190 {
 191         struct platform_device  *pdev = to_platform_device(dev);
 192         struct omap_usb *phy = platform_get_drvdata(pdev);
 193
 194         clk_disable(phy->wkupclk);
 195
 196         return 0;
 197 }
 198
 199 static int omap_usb2_runtime_resume(struct device *dev)
 200 {
 201         u32 ret = 0;
 202         struct platform_device  *pdev = to_platform_device(dev);
 203         struct omap_usb *phy = platform_get_drvdata(pdev);
 204
 205         ret = clk_enable(phy->wkupclk);
 206         if (ret < 0)
 207                 dev_err(phy->dev, "Failed to enable wkupclk %d\n", ret);
 208
 209         return ret;
 210 }
 211
 212 static const struct dev_pm_ops omap_usb2_pm_ops = {
 213         SET_RUNTIME_PM_OPS(omap_usb2_runtime_suspend, omap_usb2_runtime_resume,
 214                 NULL)
 215 };
 216
 217 #define DEV_PM_OPS     (&omap_usb2_pm_ops)
 218 #else
 219 #define DEV_PM_OPS     NULL
 220 #endif
 221
 222 #ifdef CONFIG_OF
 223 static const struct of_device_id omap_usb2_id_table[] = {
 224         { .compatible = "ti,omap-usb2" },
 225         {}
 226 };
 227 MODULE_DEVICE_TABLE(of, omap_usb2_id_table);
 228 #endif
 229
 230 static struct platform_driver omap_usb2_driver = {
 231         .probe          = omap_usb2_probe,
 232         .remove         = omap_usb2_remove,
 233         .driver         = {
 234                 .name   = "omap-usb2",
 235                 .owner  = THIS_MODULE,
 236                 .pm     = DEV_PM_OPS,
 237                 .of_match_table = of_match_ptr(omap_usb2_id_table),
 238         },
 239 };
 240
 241 module_platform_driver(omap_usb2_driver);
 242
 243 MODULE_ALIAS("platform: omap_usb2");
 244 MODULE_AUTHOR("Texas Instruments Inc.");
 245 MODULE_DESCRIPTION("OMAP USB2 phy driver");
 246 MODULE_LICENSE("GPL v2");