/*
* Driver for SMSC USB3503 USB 2.0 hub controller driver
*
* Copyright (c) 2012-2013 Dongjin Kim (tobetter@gmail.com)
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include <linux/i2c.h>
#include <linux/gpio.h>
#include <linux/delay.h>
#include <linux/slab.h>
#include <linux/module.h>
#include <linux/of_gpio.h>
#include <linux/platform_device.h>
#include <linux/platform_data/usb3503.h>
#define USB3503_VIDL 0x00
#define USB3503_VIDM 0x01
#define USB3503_PIDL 0x02
#define USB3503_PIDM 0x03
#define USB3503_DIDL 0x04
#define USB3503_DIDM 0x05
#define USB3503_CFG1 0x06
#define USB3503_SELF_BUS_PWR (1 << 7)
#define USB3503_CFG2 0x07
#define USB3503_CFG3 0x08
#define USB3503_NRD 0x09
#define USB3503_PDS 0x0a
#define USB3503_PORT1 (1 << 1)
#define USB3503_PORT2 (1 << 2)
#define USB3503_PORT3 (1 << 3)
#define USB3503_SP_ILOCK 0xe7
#define USB3503_SPILOCK_CONNECT (1 << 1)
#define USB3503_SPILOCK_CONFIG (1 << 0)
#define USB3503_CFGP 0xee
#define USB3503_CLKSUSP (1 << 7)
struct usb3503 {
enum usb3503_mode mode;
struct i2c_client *client;
int gpio_intn;
int gpio_reset;
int gpio_connect;
};
static int usb3503_write_register(struct i2c_client *client,
char reg, char data)
{
return i2c_smbus_write_byte_data(client, reg, data);
}
static int usb3503_read_register(struct i2c_client *client, char reg)
{
return i2c_smbus_read_byte_data(client, reg);
}
static int usb3503_set_bits(struct i2c_client *client, char reg, char req)
{
int err;
err = usb3503_read_register(client, reg);
if (err < 0)
return err;
err = usb3503_write_register(client, reg, err | req);
if (err < 0)
return err;
return 0;
}
static int usb3503_clear_bits(struct i2c_client *client, char reg, char req)
{
int err;
err = usb3503_read_register(client, reg);
if (err < 0)
return err;
err = usb3503_write_register(client, reg, err & ~req);
if (err < 0)
return err;
return 0;
}
static int usb3503_reset(int gpio_reset, int state)
{
if (gpio_is_valid(gpio_reset))
gpio_set_value(gpio_reset, state);
/* Wait RefClk when RESET_N is released, otherwise Hub will
* not transition to Hub Communication Stage.
*/
if (state)
msleep(100);
return 0;
}
static int usb3503_switch_mode(struct usb3503 *hub, enum usb3503_mode mode)
{
struct i2c_client *i2c = hub->client;
int err = 0;
switch (mode) {
case USB3503_MODE_HUB:
usb3503_reset(hub->gpio_reset, 1);
/* SP_ILOCK: set connect_n, config_n for config */
err = usb3503_write_register(i2c, USB3503_SP_ILOCK,
(USB3503_SPILOCK_CONNECT
| USB3503_SPILOCK_CONFIG));
if (err < 0) {
dev_err(&i2c->dev, "SP_ILOCK failed (%d)\n", err);
goto err_hubmode;
}
/* PDS : Port2,3 Disable For Self Powered Operation */
err = usb3503_set_bits(i2c, USB3503_PDS,
(USB3503_PORT2 | USB3503_PORT3));
if (err < 0) {
dev_err(&i2c->dev, "PDS failed (%d)\n", err);
goto err_hubmode;
}
/* CFG1 : SELF_BUS_PWR -> Self-Powerd operation */
err = usb3503_set_bits(i2c, USB3503_CFG1, USB3503_SELF_BUS_PWR);
if (err < 0) {
dev_err(&i2c->dev, "CFG1 failed (%d)\n", err);
goto err_hubmode;
}
/* SP_LOCK: clear connect_n, config_n for hub connect */
err = usb3503_clear_bits(i2c, USB3503_SP_ILOCK,
(USB3503_SPILOCK_CONNECT
| USB3503_SPILOCK_CONFIG));
if (err < 0) {
dev_err(&i2c->dev, "SP_ILOCK failed (%d)\n", err);
goto err_hubmode;
}
hub->mode = mode;
dev_info(&i2c->dev, "switched to HUB mode\n");
break;
case USB3503_MODE_STANDBY:
usb3503_reset(hub->gpio_reset, 0);
hub->mode = mode;
dev_info(&i2c->dev, "switched to STANDBY mode\n");
break;
default:
dev_err(&i2c->dev, "unknown mode is request\n");
err = -EINVAL;
break;
}
err_hubmode:
return err;
}
static int usb3503_probe(struct i2c_client *i2c, const struct i2c_device_id *id)
{
struct usb3503_platform_data *pdata = i2c->dev.platform_data;
struct device_node *np = i2c->dev.of_node;
struct usb3503 *hub;
int err = -ENOMEM;
u32 mode = USB3503_MODE_UNKNOWN;
hub = kzalloc(sizeof(struct usb3503), GFP_KERNEL);
if (!hub) {
dev_err(&i2c->dev, "private data alloc fail\n");
return err;
}
i2c_set_clientdata(i2c, hub);
hub->client = i2c;
if (pdata) {
hub->gpio_intn = pdata->gpio_intn;
hub->gpio_connect = pdata->gpio_connect;
hub->gpio_reset = pdata->gpio_reset;
hub->mode = pdata->initial_mode;
} else if (np) {
hub->gpio_intn = of_get_named_gpio(np, "connect-gpios", 0);
if (hub->gpio_intn == -EPROBE_DEFER)
return -EPROBE_DEFER;
hub->gpio_connect = of_get_named_gpio(np, "intn-gpios", 0);
if (hub->gpio_connect == -EPROBE_DEFER)
return -EPROBE_DEFER;
hub->gpio_reset = of_get_named_gpio(np, "reset-gpios", 0);
if (hub->gpio_reset == -EPROBE_DEFER)
return -EPROBE_DEFER;
of_property_read_u32(np, "initial-mode", &mode);
hub->mode = mode;
}
if (gpio_is_valid(hub->gpio_intn)) {
err = gpio_request_one(hub->gpio_intn,
GPIOF_OUT_INIT_HIGH, "usb3503 intn");
if (err) {
dev_err(&i2c->dev,
"unable to request GPIO %d as connect pin (%d)\n",
hub->gpio_intn, err);
goto err_out;
}
}
if (gpio_is_valid(hub->gpio_connect)) {
err = gpio_request_one(hub->gpio_connect,
GPIOF_OUT_INIT_HIGH, "usb3503 connect");
if (err) {
dev_err(&i2c->dev,
"unable to request GPIO %d as connect pin (%d)\n",
hub->gpio_connect, err);
goto err_gpio_connect;
}
}
if (gpio_is_valid(hub->gpio_reset)) {
err = gpio_request_one(hub->gpio_reset,
GPIOF_OUT_INIT_LOW, "usb3503 reset");
if (err) {
dev_err(&i2c->dev,
"unable to request GPIO %d as reset pin (%d)\n",
hub->gpio_reset, err);
goto err_gpio_reset;
}
}
usb3503_switch_mode(hub, hub->mode);
dev_info(&i2c->dev, "%s: probed on %s mode\n", __func__,
(hub->mode == USB3503_MODE_HUB) ? "hub" : "standby");
return 0;
err_gpio_reset:
if (gpio_is_valid(hub->gpio_connect))
gpio_free(hub->gpio_connect);
err_gpio_connect:
if (gpio_is_valid(hub->gpio_intn))
gpio_free(hub->gpio_intn);
err_out:
kfree(hub);
return err;
}
static int usb3503_remove(struct i2c_client *i2c)
{
struct usb3503 *hub = i2c_get_clientdata(i2c);
if (gpio_is_valid(hub->gpio_intn))
gpio_free(hub->gpio_intn);
if (gpio_is_valid(hub->gpio_connect))
gpio_free(hub->gpio_connect);
if (gpio_is_valid(hub->gpio_reset))
gpio_free(hub->gpio_reset);
kfree(hub);
return 0;
}
static const struct i2c_device_id usb3503_id[] = {
{ USB3503_I2C_NAME, 0 },
{ }
};
MODULE_DEVICE_TABLE(i2c, usb3503_id);
#ifdef CONFIG_OF
static const struct of_device_id usb3503_of_match[] = {
{ .compatible = "smsc,usb3503", },
{},
};
MODULE_DEVICE_TABLE(of, usb3503_of_match);
#endif
static struct i2c_driver usb3503_driver = {
.driver = {
.name = USB3503_I2C_NAME,
.of_match_table = of_match_ptr(usb3503_of_match),
},
.probe = usb3503_probe,
.remove = usb3503_remove,
.id_table = usb3503_id,
};
module_i2c_driver(usb3503_driver);
MODULE_AUTHOR("Dongjin Kim <tobetter@gmail.com>");
MODULE_DESCRIPTION("USB3503 USB HUB driver");
MODULE_LICENSE("GPL");