drivers/usb/phy/phy-isp1301.c

   1 /*
   2  * NXP ISP1301 USB transceiver driver
   3  *
   4  * Copyright (C) 2012 Roland Stigge
   5  *
   6  * Author: Roland Stigge <stigge@antcom.de>
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License version 2 as
  10  * published by the Free Software Foundation.
  11  */
  12
  13 #include <linux/module.h>
  14 #include <linux/mutex.h>
  15 #include <linux/i2c.h>
  16 #include <linux/usb/phy.h>
  17 #include <linux/usb/isp1301.h>
  18
  19 #define DRV_NAME                "isp1301"
  20
  21 struct isp1301 {
  22         struct usb_phy          phy;
  23         struct mutex            mutex;
  24
  25         struct i2c_client       *client;
  26 };
  27
  28 #define phy_to_isp(p)           (container_of((p), struct isp1301, phy))
  29
  30 static const struct i2c_device_id isp1301_id[] = {
  31         { "isp1301", 0 },
  32         { }
  33 };
  34 MODULE_DEVICE_TABLE(i2c, isp1301_id);
  35
  36 static struct i2c_client *isp1301_i2c_client;
  37
  38 static int __isp1301_write(struct isp1301 *isp, u8 reg, u8 value, u8 clear)
  39 {
  40         return i2c_smbus_write_byte_data(isp->client, reg | clear, value);
  41 }
  42
  43 static int isp1301_write(struct isp1301 *isp, u8 reg, u8 value)
  44 {
  45         return __isp1301_write(isp, reg, value, 0);
  46 }
  47
  48 static int isp1301_clear(struct isp1301 *isp, u8 reg, u8 value)
  49 {
  50         return __isp1301_write(isp, reg, value, ISP1301_I2C_REG_CLEAR_ADDR);
  51 }
  52
  53 static int isp1301_phy_init(struct usb_phy *phy)
  54 {
  55         struct isp1301 *isp = phy_to_isp(phy);
  56
  57         /* Disable transparent UART mode first */
  58         isp1301_clear(isp, ISP1301_I2C_MODE_CONTROL_1, MC1_UART_EN);
  59         isp1301_clear(isp, ISP1301_I2C_MODE_CONTROL_1, ~MC1_SPEED_REG);
  60         isp1301_write(isp, ISP1301_I2C_MODE_CONTROL_1, MC1_SPEED_REG);
  61         isp1301_clear(isp, ISP1301_I2C_MODE_CONTROL_2, ~0);
  62         isp1301_write(isp, ISP1301_I2C_MODE_CONTROL_2, (MC2_BI_DI | MC2_PSW_EN
  63                                 | MC2_SPD_SUSP_CTRL));
  64
  65         isp1301_clear(isp, ISP1301_I2C_OTG_CONTROL_1, ~0);
  66         isp1301_write(isp, ISP1301_I2C_MODE_CONTROL_1, MC1_DAT_SE0);
  67         isp1301_write(isp, ISP1301_I2C_OTG_CONTROL_1, (OTG1_DM_PULLDOWN
  68                                 | OTG1_DP_PULLDOWN));
  69         isp1301_clear(isp, ISP1301_I2C_OTG_CONTROL_1, (OTG1_DM_PULLUP
  70                                 | OTG1_DP_PULLUP));
  71
  72         /* mask all interrupts */
  73         isp1301_clear(isp, ISP1301_I2C_INTERRUPT_LATCH, ~0);
  74         isp1301_clear(isp, ISP1301_I2C_INTERRUPT_FALLING, ~0);
  75         isp1301_clear(isp, ISP1301_I2C_INTERRUPT_RISING, ~0);
  76
  77         return 0;
  78 }
  79
  80 static int isp1301_phy_set_vbus(struct usb_phy *phy, int on)
  81 {
  82         struct isp1301 *isp = phy_to_isp(phy);
  83
  84         if (on)
  85                 isp1301_write(isp, ISP1301_I2C_OTG_CONTROL_1, OTG1_VBUS_DRV);
  86         else
  87                 isp1301_clear(isp, ISP1301_I2C_OTG_CONTROL_1, OTG1_VBUS_DRV);
  88
  89         return 0;
  90 }
  91
  92 static int isp1301_probe(struct i2c_client *client,
  93                          const struct i2c_device_id *i2c_id)
  94 {
  95         struct isp1301 *isp;
  96         struct usb_phy *phy;
  97
  98         isp = devm_kzalloc(&client->dev, sizeof(*isp), GFP_KERNEL);
  99         if (!isp)
 100                 return -ENOMEM;
 101
 102         isp->client = client;
 103         mutex_init(&isp->mutex);
 104
 105         phy = &isp->phy;
 106         phy->dev = &client->dev;
 107         phy->label = DRV_NAME;
 108         phy->init = isp1301_phy_init;
 109         phy->set_vbus = isp1301_phy_set_vbus;
 110         phy->type = USB_PHY_TYPE_USB2;
 111
 112         i2c_set_clientdata(client, isp);
 113         usb_add_phy_dev(phy);
 114
 115         isp1301_i2c_client = client;
 116
 117         return 0;
 118 }
 119
 120 static int isp1301_remove(struct i2c_client *client)
 121 {
 122         struct isp1301 *isp = i2c_get_clientdata(client);
 123
 124         usb_remove_phy(&isp->phy);
 125         isp1301_i2c_client = NULL;
 126
 127         return 0;
 128 }
 129
 130 static struct i2c_driver isp1301_driver = {
 131         .driver = {
 132                 .name = DRV_NAME,
 133         },
 134         .probe = isp1301_probe,
 135         .remove = isp1301_remove,
 136         .id_table = isp1301_id,
 137 };
 138
 139 module_i2c_driver(isp1301_driver);
 140
 141 static int match(struct device *dev, void *data)
 142 {
 143         struct device_node *node = (struct device_node *)data;
 144         return (dev->of_node == node) &&
 145                 (dev->driver == &isp1301_driver.driver);
 146 }
 147
 148 struct i2c_client *isp1301_get_client(struct device_node *node)
 149 {
 150         if (node) { /* reference of ISP1301 I2C node via DT */
 151                 struct device *dev = bus_find_device(&i2c_bus_type, NULL,
 152                                                      node, match);
 153                 if (!dev)
 154                         return NULL;
 155                 return to_i2c_client(dev);
 156         } else { /* non-DT: only one ISP1301 chip supported */
 157                 return isp1301_i2c_client;
 158         }
 159 }
 160 EXPORT_SYMBOL_GPL(isp1301_get_client);
 161
 162 MODULE_AUTHOR("Roland Stigge <stigge@antcom.de>");
 163 MODULE_DESCRIPTION("NXP ISP1301 USB transceiver driver");
 164 MODULE_LICENSE("GPL");