drivers/usb/misc/usb3503.c - linux - Git at Google

 /*
  * 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");
	/*
	* 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");