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_specific_cable_nb vbus_dev;
  34         struct extcon_specific_cable_nb id_dev;
  35         struct notifier_block           vbus_nb;
  36         struct notifier_block           id_nb;
  37 };
  38
  39 #define OMAP_OTG_CTRL           0x0c
  40 #define OMAP_OTG_ASESSVLD       (1 << 20)
  41 #define OMAP_OTG_BSESSEND       (1 << 19)
  42 #define OMAP_OTG_BSESSVLD       (1 << 18)
  43 #define OMAP_OTG_VBUSVLD        (1 << 17)
  44 #define OMAP_OTG_ID             (1 << 16)
  45 #define OMAP_OTG_XCEIV_OUTPUTS \
  46         (OMAP_OTG_ASESSVLD | OMAP_OTG_BSESSEND | OMAP_OTG_BSESSVLD | \
  47          OMAP_OTG_VBUSVLD  | OMAP_OTG_ID)
  48
  49 static void omap_otg_ctrl(struct otg_device *otg_dev, u32 outputs)
  50 {
  51         u32 l;
  52
  53         l = readl(otg_dev->base + OMAP_OTG_CTRL);
  54         l &= ~OMAP_OTG_XCEIV_OUTPUTS;
  55         l |= outputs;
  56         writel(l, otg_dev->base + OMAP_OTG_CTRL);
  57 }
  58
  59 static void omap_otg_set_mode(struct otg_device *otg_dev)
  60 {
  61         if (!otg_dev->id && otg_dev->vbus)
  62                 /* Set B-session valid. */
  63                 omap_otg_ctrl(otg_dev, OMAP_OTG_ID | OMAP_OTG_BSESSVLD);
  64         else if (otg_dev->vbus)
  65                 /* Set A-session valid. */
  66                 omap_otg_ctrl(otg_dev, OMAP_OTG_ASESSVLD);
  67         else if (!otg_dev->id)
  68                 /* Set B-session end to indicate no VBUS. */
  69                 omap_otg_ctrl(otg_dev, OMAP_OTG_ID | OMAP_OTG_BSESSEND);
  70 }
  71
  72 static int omap_otg_id_notifier(struct notifier_block *nb,
  73                                 unsigned long event, void *ptr)
  74 {
  75         struct otg_device *otg_dev = container_of(nb, struct otg_device, id_nb);
  76
  77         otg_dev->id = event;
  78         omap_otg_set_mode(otg_dev);
  79
  80         return NOTIFY_DONE;
  81 }
  82
  83 static int omap_otg_vbus_notifier(struct notifier_block *nb,
  84                                   unsigned long event, void *ptr)
  85 {
  86         struct otg_device *otg_dev = container_of(nb, struct otg_device,
  87                                                   vbus_nb);
  88
  89         otg_dev->vbus = event;
  90         omap_otg_set_mode(otg_dev);
  91
  92         return NOTIFY_DONE;
  93 }
  94
  95 static int omap_otg_probe(struct platform_device *pdev)
  96 {
  97         const struct omap_usb_config *config = pdev->dev.platform_data;
  98         struct otg_device *otg_dev;
  99         struct extcon_dev *extcon;
 100         int ret;
 101         u32 rev;
 102
 103         if (!config || !config->extcon)
 104                 return -ENODEV;
 105
 106         extcon = extcon_get_extcon_dev(config->extcon);
 107         if (!extcon)
 108                 return -EPROBE_DEFER;
 109
 110         otg_dev = devm_kzalloc(&pdev->dev, sizeof(*otg_dev), GFP_KERNEL);
 111         if (!otg_dev)
 112                 return -ENOMEM;
 113
 114         otg_dev->base = devm_ioremap_resource(&pdev->dev, &pdev->resource[0]);
 115         if (IS_ERR(otg_dev->base))
 116                 return PTR_ERR(otg_dev->base);
 117
 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_interest(&otg_dev->id_dev, config->extcon,
 122                                        "USB-HOST", &otg_dev->id_nb);
 123         if (ret)
 124                 return ret;
 125
 126         ret = extcon_register_interest(&otg_dev->vbus_dev, config->extcon,
 127                                        "USB", &otg_dev->vbus_nb);
 128         if (ret) {
 129                 extcon_unregister_interest(&otg_dev->id_dev);
 130                 return ret;
 131         }
 132
 133         otg_dev->id = extcon_get_cable_state(extcon, "USB-HOST");
 134         otg_dev->vbus = extcon_get_cable_state(extcon, "USB");
 135         omap_otg_set_mode(otg_dev);
 136
 137         rev = readl(otg_dev->base);
 138
 139         dev_info(&pdev->dev,
 140                  "OMAP USB OTG controller rev %d.%d (%s, id=%d, vbus=%d)\n",
 141                  (rev >> 4) & 0xf, rev & 0xf, config->extcon, otg_dev->id,
 142                  otg_dev->vbus);
 143
 144         return 0;
 145 }
 146
 147 static int omap_otg_remove(struct platform_device *pdev)
 148 {
 149         struct otg_device *otg_dev = platform_get_drvdata(pdev);
 150
 151         extcon_unregister_interest(&otg_dev->id_dev);
 152         extcon_unregister_interest(&otg_dev->vbus_dev);
 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>");