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

   1 /*
   2  * OMAP OTG controller driver
   3  *
   4  * Based on code from tahvo-usb.c and isp1301_omap.c drivers.
   5  *
   6  * Copyright (C) 2005-2006 Nokia Corporation
   7  * Copyright (C) 2004 Texas Instruments
   8  * Copyright (C) 2004 David Brownell
   9  *
  10  * This file is subject to the terms and conditions of the GNU General
  11  * Public License. See the file "COPYING" in the main directory of this
  12  * archive for more details.
  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/io.h>
  21 #include <linux/err.h>
  22 #include <linux/extcon.h>
  23 #include <linux/kernel.h>
  24 #include <linux/module.h>
  25 #include <linux/interrupt.h>
  26 #include <linux/platform_device.h>
  27 #include <linux/platform_data/usb-omap1.h>
  28
  29 struct otg_device {
  30         void __iomem                    *base;
  31         bool                            id;
  32         bool                            vbus;
  33         struct extcon_dev               *extcon;
  34         struct notifier_block           vbus_nb;
  35         struct notifier_block           id_nb;
  36 };
  37
  38 #define OMAP_OTG_CTRL           0x0c
  39 #define OMAP_OTG_ASESSVLD       (1 << 20)
  40 #define OMAP_OTG_BSESSEND       (1 << 19)
  41 #define OMAP_OTG_BSESSVLD       (1 << 18)
  42 #define OMAP_OTG_VBUSVLD        (1 << 17)
  43 #define OMAP_OTG_ID             (1 << 16)
  44 #define OMAP_OTG_XCEIV_OUTPUTS \
  45         (OMAP_OTG_ASESSVLD | OMAP_OTG_BSESSEND | OMAP_OTG_BSESSVLD | \
  46          OMAP_OTG_VBUSVLD  | OMAP_OTG_ID)
  47
  48 static void omap_otg_ctrl(struct otg_device *otg_dev, u32 outputs)
  49 {
  50         u32 l;
  51
  52         l = readl(otg_dev->base + OMAP_OTG_CTRL);
  53         l &= ~OMAP_OTG_XCEIV_OUTPUTS;
  54         l |= outputs;
  55         writel(l, otg_dev->base + OMAP_OTG_CTRL);
  56 }
  57
  58 static void omap_otg_set_mode(struct otg_device *otg_dev)
  59 {
  60         if (!otg_dev->id && otg_dev->vbus)
  61                 /* Set B-session valid. */
  62                 omap_otg_ctrl(otg_dev, OMAP_OTG_ID | OMAP_OTG_BSESSVLD);
  63         else if (otg_dev->vbus)
  64                 /* Set A-session valid. */
  65                 omap_otg_ctrl(otg_dev, OMAP_OTG_ASESSVLD);
  66         else if (!otg_dev->id)
  67                 /* Set B-session end to indicate no VBUS. */
  68                 omap_otg_ctrl(otg_dev, OMAP_OTG_ID | OMAP_OTG_BSESSEND);
  69 }
  70
  71 static int omap_otg_id_notifier(struct notifier_block *nb,
  72                                 unsigned long event, void *ptr)
  73 {
  74         struct otg_device *otg_dev = container_of(nb, struct otg_device, id_nb);
  75
  76         otg_dev->id = event;
  77         omap_otg_set_mode(otg_dev);
  78
  79         return NOTIFY_DONE;
  80 }
  81
  82 static int omap_otg_vbus_notifier(struct notifier_block *nb,
  83                                   unsigned long event, void *ptr)
  84 {
  85         struct otg_device *otg_dev = container_of(nb, struct otg_device,
  86                                                   vbus_nb);
  87
  88         otg_dev->vbus = event;
  89         omap_otg_set_mode(otg_dev);
  90
  91         return NOTIFY_DONE;
  92 }
  93
  94 static int omap_otg_probe(struct platform_device *pdev)
  95 {
  96         const struct omap_usb_config *config = pdev->dev.platform_data;
  97         struct otg_device *otg_dev;
  98         struct extcon_dev *extcon;
  99         int ret;
 100         u32 rev;
 101
 102         if (!config || !config->extcon)
 103                 return -ENODEV;
 104
 105         extcon = extcon_get_extcon_dev(config->extcon);
 106         if (!extcon)
 107                 return -EPROBE_DEFER;
 108
 109         otg_dev = devm_kzalloc(&pdev->dev, sizeof(*otg_dev), GFP_KERNEL);
 110         if (!otg_dev)
 111                 return -ENOMEM;
 112
 113         otg_dev->base = devm_ioremap_resource(&pdev->dev, &pdev->resource[0]);
 114         if (IS_ERR(otg_dev->base))
 115                 return PTR_ERR(otg_dev->base);
 116
 117         otg_dev->extcon = extcon;
 118         otg_dev->id_nb.notifier_call = omap_otg_id_notifier;
 119         otg_dev->vbus_nb.notifier_call = omap_otg_vbus_notifier;
 120
 121         ret = extcon_register_notifier(extcon, EXTCON_USB_HOST, &otg_dev->id_nb);
 122         if (ret)
 123                 return ret;
 124
 125         ret = extcon_register_notifier(extcon, EXTCON_USB, &otg_dev->vbus_nb);
 126         if (ret) {
 127                 extcon_unregister_notifier(extcon, EXTCON_USB_HOST,
 128                                         &otg_dev->id_nb);
 129                 return ret;
 130         }
 131
 132         otg_dev->id = extcon_get_cable_state_(extcon, EXTCON_USB_HOST);
 133         otg_dev->vbus = extcon_get_cable_state_(extcon, EXTCON_USB);
 134         omap_otg_set_mode(otg_dev);
 135
 136         rev = readl(otg_dev->base);
 137
 138         dev_info(&pdev->dev,
 139                  "OMAP USB OTG controller rev %d.%d (%s, id=%d, vbus=%d)\n",
 140                  (rev >> 4) & 0xf, rev & 0xf, config->extcon, otg_dev->id,
 141                  otg_dev->vbus);
 142
 143         return 0;
 144 }
 145
 146 static int omap_otg_remove(struct platform_device *pdev)
 147 {
 148         struct otg_device *otg_dev = platform_get_drvdata(pdev);
 149         struct extcon_dev *edev = otg_dev->extcon;
 150
 151         extcon_unregister_notifier(edev, EXTCON_USB_HOST,&otg_dev->id_nb);
 152         extcon_unregister_notifier(edev, EXTCON_USB, &otg_dev->vbus_nb);
 153
 154         return 0;
 155 }
 156
 157 static struct platform_driver omap_otg_driver = {
 158         .probe          = omap_otg_probe,
 159         .remove         = omap_otg_remove,
 160         .driver         = {
 161                 .name   = "omap_otg",
 162         },
 163 };
 164 module_platform_driver(omap_otg_driver);
 165
 166 MODULE_DESCRIPTION("OMAP USB OTG controller driver");
 167 MODULE_LICENSE("GPL");
 168 MODULE_AUTHOR("Aaro Koskinen <aaro.koskinen@iki.fi>");