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
  35 static struct i2c_client *isp1301_i2c_client;
  36
  37 static int __isp1301_write(struct isp1301 *isp, u8 reg, u8 value, u8 clear)
  38 {
  39         return i2c_smbus_write_byte_data(isp->client, reg | clear, value);
  40 }
  41
  42 static int isp1301_write(struct isp1301 *isp, u8 reg, u8 value)
  43 {
  44         return __isp1301_write(isp, reg, value, 0);
  45 }
  46
  47 static int isp1301_clear(struct isp1301 *isp, u8 reg, u8 value)
  48 {
  49         return __isp1301_write(isp, reg, value, ISP1301_I2C_REG_CLEAR_ADDR);
  50 }
  51
  52 static int isp1301_phy_init(struct usb_phy *phy)
  53 {
  54         struct isp1301 *isp = phy_to_isp(phy);
  55
  56         /* Disable transparent UART mode first */
  57         isp1301_clear(isp, ISP1301_I2C_MODE_CONTROL_1, MC1_UART_EN);
  58         isp1301_clear(isp, ISP1301_I2C_MODE_CONTROL_1, ~MC1_SPEED_REG);
  59         isp1301_write(isp, ISP1301_I2C_MODE_CONTROL_1, MC1_SPEED_REG);
  60         isp1301_clear(isp, ISP1301_I2C_MODE_CONTROL_2, ~0);
  61         isp1301_write(isp, ISP1301_I2C_MODE_CONTROL_2, (MC2_BI_DI | MC2_PSW_EN
  62                                 | MC2_SPD_SUSP_CTRL));
  63
  64         isp1301_clear(isp, ISP1301_I2C_OTG_CONTROL_1, ~0);
  65         isp1301_write(isp, ISP1301_I2C_MODE_CONTROL_1, MC1_DAT_SE0);
  66         isp1301_write(isp, ISP1301_I2C_OTG_CONTROL_1, (OTG1_DM_PULLDOWN
  67                                 | OTG1_DP_PULLDOWN));
  68         isp1301_clear(isp, ISP1301_I2C_OTG_CONTROL_1, (OTG1_DM_PULLUP
  69                                 | OTG1_DP_PULLUP));
  70
  71         /* mask all interrupts */
  72         isp1301_clear(isp, ISP1301_I2C_INTERRUPT_LATCH, ~0);
  73         isp1301_clear(isp, ISP1301_I2C_INTERRUPT_FALLING, ~0);
  74         isp1301_clear(isp, ISP1301_I2C_INTERRUPT_RISING, ~0);
  75
  76         return 0;
  77 }
  78
  79 static int isp1301_phy_set_vbus(struct usb_phy *phy, int on)
  80 {
  81         struct isp1301 *isp = phy_to_isp(phy);
  82
  83         if (on)
  84                 isp1301_write(isp, ISP1301_I2C_OTG_CONTROL_1, OTG1_VBUS_DRV);
  85         else
  86                 isp1301_clear(isp, ISP1301_I2C_OTG_CONTROL_1, OTG1_VBUS_DRV);
  87
  88         return 0;
  89 }
  90
  91 static int isp1301_probe(struct i2c_client *client,
  92                          const struct i2c_device_id *i2c_id)
  93 {
  94         struct isp1301 *isp;
  95         struct usb_phy *phy;
  96
  97         isp = devm_kzalloc(&client->dev, sizeof(*isp), GFP_KERNEL);
  98         if (!isp)
  99                 return -ENOMEM;
 100
 101         isp->client = client;
 102         mutex_init(&isp->mutex);
 103
 104         phy = &isp->phy;
 105         phy->dev = &client->dev;
 106         phy->label = DRV_NAME;
 107         phy->init = isp1301_phy_init;
 108         phy->set_vbus = isp1301_phy_set_vbus;
 109         phy->type = USB_PHY_TYPE_USB2;
 110
 111         i2c_set_clientdata(client, isp);
 112         usb_add_phy_dev(phy);
 113
 114         isp1301_i2c_client = client;
 115
 116         return 0;
 117 }
 118
 119 static int isp1301_remove(struct i2c_client *client)
 120 {
 121         struct isp1301 *isp = i2c_get_clientdata(client);
 122
 123         usb_remove_phy(&isp->phy);
 124         isp1301_i2c_client = NULL;
 125
 126         return 0;
 127 }
 128
 129 static struct i2c_driver isp1301_driver = {
 130         .driver = {
 131                 .name = DRV_NAME,
 132         },
 133         .probe = isp1301_probe,
 134         .remove = isp1301_remove,
 135         .id_table = isp1301_id,
 136 };
 137
 138 module_i2c_driver(isp1301_driver);
 139
 140 static int match(struct device *dev, void *data)
 141 {
 142         struct device_node *node = (struct device_node *)data;
 143         return (dev->of_node == node) &&
 144                 (dev->driver == &isp1301_driver.driver);
 145 }
 146
 147 struct i2c_client *isp1301_get_client(struct device_node *node)
 148 {
 149         if (node) { /* reference of ISP1301 I2C node via DT */
 150                 struct device *dev = bus_find_device(&i2c_bus_type, NULL,
 151                                                      node, match);
 152                 if (!dev)
 153                         return NULL;
 154                 return to_i2c_client(dev);
 155         } else { /* non-DT: only one ISP1301 chip supported */
 156                 return isp1301_i2c_client;
 157         }
 158 }
 159 EXPORT_SYMBOL_GPL(isp1301_get_client);
 160
 161 MODULE_AUTHOR("Roland Stigge <stigge@antcom.de>");
 162 MODULE_DESCRIPTION("NXP ISP1301 USB transceiver driver");
 163 MODULE_LICENSE("GPL");