drivers/usb/phy/phy-generic.c - kernel/bruno - Git at Google

 /*
  * NOP USB transceiver for all USB transceiver which are either built-in
  * into USB IP or which are mostly autonomous.
  *
  * Copyright (C) 2009 Texas Instruments Inc
  * Author: Ajay Kumar Gupta <ajay.gupta@ti.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., 675 Mass Ave, Cambridge, MA 02139, USA.
  *
  * Current status:
  *	This provides a "nop" transceiver for PHYs which are
  *	autonomous such as isp1504, isp1707, etc.
  */

 #include <linux/module.h>
 #include <linux/platform_device.h>
 #include <linux/dma-mapping.h>
 #include <linux/usb/gadget.h>
 #include <linux/usb/otg.h>
 #include <linux/usb/usb_phy_generic.h>
 #include <linux/slab.h>
 #include <linux/clk.h>
 #include <linux/regulator/consumer.h>
 #include <linux/of.h>
 #include <linux/of_gpio.h>
 #include <linux/gpio.h>
 #include <linux/delay.h>

 #include "phy-generic.h"

 #define VBUS_IRQ_FLAGS \
 	(IRQF_SHARED | IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING | \
 		IRQF_ONESHOT)

 struct platform_device *usb_phy_generic_register(void)
 {
 	return platform_device_register_simple("usb_phy_generic",
 			PLATFORM_DEVID_AUTO, NULL, 0);
 }
 EXPORT_SYMBOL_GPL(usb_phy_generic_register);

 void usb_phy_generic_unregister(struct platform_device *pdev)
 {
 	platform_device_unregister(pdev);
 }
 EXPORT_SYMBOL_GPL(usb_phy_generic_unregister);

 static int nop_set_suspend(struct usb_phy *x, int suspend)
 {
 	return 0;
 }

 static void nop_reset(struct usb_phy_generic *nop)
 {
 	if (!nop->gpiod_reset)
 		return;

 	gpiod_set_value(nop->gpiod_reset, 1);
 	usleep_range(10000, 20000);
 	gpiod_set_value(nop->gpiod_reset, 0);
 }

 /* interface to regulator framework */
 static void nop_set_vbus_draw(struct usb_phy_generic *nop, unsigned mA)
 {
 	struct regulator *vbus_draw = nop->vbus_draw;
 	int enabled;
 	int ret;

 	if (!vbus_draw)
 		return;

 	enabled = nop->vbus_draw_enabled;
 	if (mA) {
 		regulator_set_current_limit(vbus_draw, 0, 1000 * mA);
 		if (!enabled) {
 			ret = regulator_enable(vbus_draw);
 			if (ret < 0)
 				return;
 			nop->vbus_draw_enabled = 1;
 		}
 	} else {
 		if (enabled) {
 			ret = regulator_disable(vbus_draw);
 			if (ret < 0)
 				return;
 			nop->vbus_draw_enabled = 0;
 		}
 	}
 	nop->mA = mA;
 }


 static irqreturn_t nop_gpio_vbus_thread(int irq, void *data)
 {
 	struct usb_phy_generic *nop = data;
 	struct usb_otg *otg = nop->phy.otg;
 	int vbus, status;

 	vbus = gpiod_get_value(nop->gpiod_vbus);
 	if ((vbus ^ nop->vbus) == 0)
 		return IRQ_HANDLED;
 	nop->vbus = vbus;

 	if (vbus) {
 		status = USB_EVENT_VBUS;
 		otg->state = OTG_STATE_B_PERIPHERAL;
 		nop->phy.last_event = status;
 		usb_gadget_vbus_connect(otg->gadget);

 		/* drawing a "unit load" is *always* OK, except for OTG */
 		nop_set_vbus_draw(nop, 100);

 		atomic_notifier_call_chain(&nop->phy.notifier, status,
 					   otg->gadget);
 	} else {
 		nop_set_vbus_draw(nop, 0);

 		usb_gadget_vbus_disconnect(otg->gadget);
 		status = USB_EVENT_NONE;
 		otg->state = OTG_STATE_B_IDLE;
 		nop->phy.last_event = status;

 		atomic_notifier_call_chain(&nop->phy.notifier, status,
 					   otg->gadget);
 	}
 	return IRQ_HANDLED;
 }

 int usb_gen_phy_init(struct usb_phy *phy)
 {
 	struct usb_phy_generic *nop = dev_get_drvdata(phy->dev);

 	if (!IS_ERR(nop->vcc)) {
 		if (regulator_enable(nop->vcc))
 			dev_err(phy->dev, "Failed to enable power\n");
 	}

 	if (!IS_ERR(nop->clk))
 		clk_prepare_enable(nop->clk);

 	nop_reset(nop);

 	return 0;
 }
 EXPORT_SYMBOL_GPL(usb_gen_phy_init);

 void usb_gen_phy_shutdown(struct usb_phy *phy)
 {
 	struct usb_phy_generic *nop = dev_get_drvdata(phy->dev);

 	gpiod_set_value(nop->gpiod_reset, 1);

 	if (!IS_ERR(nop->clk))
 		clk_disable_unprepare(nop->clk);

 	if (!IS_ERR(nop->vcc)) {
 		if (regulator_disable(nop->vcc))
 			dev_err(phy->dev, "Failed to disable power\n");
 	}
 }
 EXPORT_SYMBOL_GPL(usb_gen_phy_shutdown);

 static int nop_set_peripheral(struct usb_otg *otg, struct usb_gadget *gadget)
 {
 	if (!otg)
 		return -ENODEV;

 	if (!gadget) {
 		otg->gadget = NULL;
 		return -ENODEV;
 	}

 	otg->gadget = gadget;
 	otg->state = OTG_STATE_B_IDLE;
 	return 0;
 }

 static int nop_set_host(struct usb_otg *otg, struct usb_bus *host)
 {
 	if (!otg)
 		return -ENODEV;

 	if (!host) {
 		otg->host = NULL;
 		return -ENODEV;
 	}

 	otg->host = host;
 	return 0;
 }

 int usb_phy_gen_create_phy(struct device *dev, struct usb_phy_generic *nop,
 		struct usb_phy_generic_platform_data *pdata)
 {
 	enum usb_phy_type type = USB_PHY_TYPE_USB2;
 	int err = 0;

 	u32 clk_rate = 0;
 	bool needs_vcc = false;

 	if (dev->of_node) {
 		struct device_node *node = dev->of_node;

 		if (of_property_read_u32(node, "clock-frequency", &clk_rate))
 			clk_rate = 0;

 		needs_vcc = of_property_read_bool(node, "vcc-supply");
 		nop->gpiod_reset = devm_gpiod_get_optional(dev, "reset",
 							   GPIOD_ASIS);
 		err = PTR_ERR_OR_ZERO(nop->gpiod_reset);
 		if (!err) {
 			nop->gpiod_vbus = devm_gpiod_get_optional(dev,
 							 "vbus-detect",
 							 GPIOD_ASIS);
 			err = PTR_ERR_OR_ZERO(nop->gpiod_vbus);
 		}
 	} else if (pdata) {
 		type = pdata->type;
 		clk_rate = pdata->clk_rate;
 		needs_vcc = pdata->needs_vcc;
 		if (gpio_is_valid(pdata->gpio_reset)) {
 			err = devm_gpio_request_one(dev, pdata->gpio_reset,
 						    GPIOF_ACTIVE_LOW,
 						    dev_name(dev));
 			if (!err)
 				nop->gpiod_reset =
 					gpio_to_desc(pdata->gpio_reset);
 		}
 		nop->gpiod_vbus = pdata->gpiod_vbus;
 	}

 	if (err == -EPROBE_DEFER)
 		return -EPROBE_DEFER;
 	if (err) {
 		dev_err(dev, "Error requesting RESET or VBUS GPIO\n");
 		return err;
 	}
 	if (nop->gpiod_reset)
 		gpiod_direction_output(nop->gpiod_reset, 1);

 	nop->phy.otg = devm_kzalloc(dev, sizeof(*nop->phy.otg),
 			GFP_KERNEL);
 	if (!nop->phy.otg)
 		return -ENOMEM;

 	nop->clk = devm_clk_get(dev, "main_clk");
 	if (IS_ERR(nop->clk)) {
 		dev_dbg(dev, "Can't get phy clock: %ld\n",
 					PTR_ERR(nop->clk));
 	}

 	if (!IS_ERR(nop->clk) && clk_rate) {
 		err = clk_set_rate(nop->clk, clk_rate);
 		if (err) {
 			dev_err(dev, "Error setting clock rate\n");
 			return err;
 		}
 	}

 	nop->vcc = devm_regulator_get(dev, "vcc");
 	if (IS_ERR(nop->vcc)) {
 		dev_dbg(dev, "Error getting vcc regulator: %ld\n",
 					PTR_ERR(nop->vcc));
 		if (needs_vcc)
 			return -EPROBE_DEFER;
 	}

 	nop->dev		= dev;
 	nop->phy.dev		= nop->dev;
 	nop->phy.label		= "nop-xceiv";
 	nop->phy.set_suspend	= nop_set_suspend;
 	nop->phy.type		= type;

 	nop->phy.otg->state		= OTG_STATE_UNDEFINED;
 	nop->phy.otg->usb_phy		= &nop->phy;
 	nop->phy.otg->set_host		= nop_set_host;
 	nop->phy.otg->set_peripheral	= nop_set_peripheral;

 	return 0;
 }
 EXPORT_SYMBOL_GPL(usb_phy_gen_create_phy);

 static int usb_phy_generic_probe(struct platform_device *pdev)
 {
 	struct device *dev = &pdev->dev;
 	struct usb_phy_generic	*nop;
 	int err;

 	nop = devm_kzalloc(dev, sizeof(*nop), GFP_KERNEL);
 	if (!nop)
 		return -ENOMEM;

 	err = usb_phy_gen_create_phy(dev, nop, dev_get_platdata(&pdev->dev));
 	if (err)
 		return err;
 	if (nop->gpiod_vbus) {
 		err = devm_request_threaded_irq(&pdev->dev,
 						gpiod_to_irq(nop->gpiod_vbus),
 						NULL, nop_gpio_vbus_thread,
 						VBUS_IRQ_FLAGS, "vbus_detect",
 						nop);
 		if (err) {
 			dev_err(&pdev->dev, "can't request irq %i, err: %d\n",
 				gpiod_to_irq(nop->gpiod_vbus), err);
 			return err;
 		}
 	}

 	nop->phy.init		= usb_gen_phy_init;
 	nop->phy.shutdown	= usb_gen_phy_shutdown;

 	err = usb_add_phy_dev(&nop->phy);
 	if (err) {
 		dev_err(&pdev->dev, "can't register transceiver, err: %d\n",
 			err);
 		return err;
 	}

 	platform_set_drvdata(pdev, nop);

 	return 0;
 }

 static int usb_phy_generic_remove(struct platform_device *pdev)
 {
 	struct usb_phy_generic *nop = platform_get_drvdata(pdev);

 	usb_remove_phy(&nop->phy);

 	return 0;
 }

 static const struct of_device_id nop_xceiv_dt_ids[] = {
 	{ .compatible = "usb-nop-xceiv" },
 	{ }
 };

 MODULE_DEVICE_TABLE(of, nop_xceiv_dt_ids);

 static struct platform_driver usb_phy_generic_driver = {
 	.probe		= usb_phy_generic_probe,
 	.remove		= usb_phy_generic_remove,
 	.driver		= {
 		.name	= "usb_phy_generic",
 		.of_match_table = nop_xceiv_dt_ids,
 	},
 };

 static int __init usb_phy_generic_init(void)
 {
 	return platform_driver_register(&usb_phy_generic_driver);
 }
 subsys_initcall(usb_phy_generic_init);

 static void __exit usb_phy_generic_exit(void)
 {
 	platform_driver_unregister(&usb_phy_generic_driver);
 }
 module_exit(usb_phy_generic_exit);

 MODULE_ALIAS("platform:usb_phy_generic");
 MODULE_AUTHOR("Texas Instruments Inc");
 MODULE_DESCRIPTION("NOP USB Transceiver driver");
 MODULE_LICENSE("GPL");
	/*
	* NOP USB transceiver for all USB transceiver which are either built-in
	* into USB IP or which are mostly autonomous.
	*
	* Copyright (C) 2009 Texas Instruments Inc
	* Author: Ajay Kumar Gupta <ajay.gupta@ti.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., 675 Mass Ave, Cambridge, MA 02139, USA.
	*
	* Current status:
	* This provides a "nop" transceiver for PHYs which are
	* autonomous such as isp1504, isp1707, etc.
	*/

	#include <linux/module.h>
	#include <linux/platform_device.h>
	#include <linux/dma-mapping.h>
	#include <linux/usb/gadget.h>
	#include <linux/usb/otg.h>
	#include <linux/usb/usb_phy_generic.h>
	#include <linux/slab.h>
	#include <linux/clk.h>
	#include <linux/regulator/consumer.h>
	#include <linux/of.h>
	#include <linux/of_gpio.h>
	#include <linux/gpio.h>
	#include <linux/delay.h>

	#include "phy-generic.h"

	#define VBUS_IRQ_FLAGS \
	(IRQF_SHARED \| IRQF_TRIGGER_RISING \| IRQF_TRIGGER_FALLING \| \
	IRQF_ONESHOT)

	struct platform_device *usb_phy_generic_register(void)
	{
	return platform_device_register_simple("usb_phy_generic",
	PLATFORM_DEVID_AUTO, NULL, 0);
	}
	EXPORT_SYMBOL_GPL(usb_phy_generic_register);

	void usb_phy_generic_unregister(struct platform_device *pdev)
	{
	platform_device_unregister(pdev);
	}
	EXPORT_SYMBOL_GPL(usb_phy_generic_unregister);

	static int nop_set_suspend(struct usb_phy *x, int suspend)
	{
	return 0;
	}

	static void nop_reset(struct usb_phy_generic *nop)
	{
	if (!nop->gpiod_reset)
	return;

	gpiod_set_value(nop->gpiod_reset, 1);
	usleep_range(10000, 20000);
	gpiod_set_value(nop->gpiod_reset, 0);
	}

	/* interface to regulator framework */
	static void nop_set_vbus_draw(struct usb_phy_generic *nop, unsigned mA)
	{
	struct regulator *vbus_draw = nop->vbus_draw;
	int enabled;
	int ret;

	if (!vbus_draw)
	return;

	enabled = nop->vbus_draw_enabled;
	if (mA) {
	regulator_set_current_limit(vbus_draw, 0, 1000 * mA);
	if (!enabled) {
	ret = regulator_enable(vbus_draw);
	if (ret < 0)
	return;
	nop->vbus_draw_enabled = 1;
	}
	} else {
	if (enabled) {
	ret = regulator_disable(vbus_draw);
	if (ret < 0)
	return;
	nop->vbus_draw_enabled = 0;
	}
	}
	nop->mA = mA;
	}


	static irqreturn_t nop_gpio_vbus_thread(int irq, void *data)
	{
	struct usb_phy_generic *nop = data;
	struct usb_otg *otg = nop->phy.otg;
	int vbus, status;

	vbus = gpiod_get_value(nop->gpiod_vbus);
	if ((vbus ^ nop->vbus) == 0)
	return IRQ_HANDLED;
	nop->vbus = vbus;

	if (vbus) {
	status = USB_EVENT_VBUS;
	otg->state = OTG_STATE_B_PERIPHERAL;
	nop->phy.last_event = status;
	usb_gadget_vbus_connect(otg->gadget);

	/* drawing a "unit load" is always OK, except for OTG */
	nop_set_vbus_draw(nop, 100);

	atomic_notifier_call_chain(&nop->phy.notifier, status,
	otg->gadget);
	} else {
	nop_set_vbus_draw(nop, 0);

	usb_gadget_vbus_disconnect(otg->gadget);
	status = USB_EVENT_NONE;
	otg->state = OTG_STATE_B_IDLE;
	nop->phy.last_event = status;

	atomic_notifier_call_chain(&nop->phy.notifier, status,
	otg->gadget);
	}
	return IRQ_HANDLED;
	}

	int usb_gen_phy_init(struct usb_phy *phy)
	{
	struct usb_phy_generic *nop = dev_get_drvdata(phy->dev);

	if (!IS_ERR(nop->vcc)) {
	if (regulator_enable(nop->vcc))
	dev_err(phy->dev, "Failed to enable power\n");
	}

	if (!IS_ERR(nop->clk))
	clk_prepare_enable(nop->clk);

	nop_reset(nop);

	return 0;
	}
	EXPORT_SYMBOL_GPL(usb_gen_phy_init);

	void usb_gen_phy_shutdown(struct usb_phy *phy)
	{
	struct usb_phy_generic *nop = dev_get_drvdata(phy->dev);

	gpiod_set_value(nop->gpiod_reset, 1);

	if (!IS_ERR(nop->clk))
	clk_disable_unprepare(nop->clk);

	if (!IS_ERR(nop->vcc)) {
	if (regulator_disable(nop->vcc))
	dev_err(phy->dev, "Failed to disable power\n");
	}
	}
	EXPORT_SYMBOL_GPL(usb_gen_phy_shutdown);

	static int nop_set_peripheral(struct usb_otg otg, struct usb_gadget gadget)
	{
	if (!otg)
	return -ENODEV;

	if (!gadget) {
	otg->gadget = NULL;
	return -ENODEV;
	}

	otg->gadget = gadget;
	otg->state = OTG_STATE_B_IDLE;
	return 0;
	}

	static int nop_set_host(struct usb_otg otg, struct usb_bus host)
	{
	if (!otg)
	return -ENODEV;

	if (!host) {
	otg->host = NULL;
	return -ENODEV;
	}

	otg->host = host;
	return 0;
	}

	int usb_phy_gen_create_phy(struct device dev, struct usb_phy_generic nop,
	struct usb_phy_generic_platform_data *pdata)
	{
	enum usb_phy_type type = USB_PHY_TYPE_USB2;
	int err = 0;

	u32 clk_rate = 0;
	bool needs_vcc = false;

	if (dev->of_node) {
	struct device_node *node = dev->of_node;

	if (of_property_read_u32(node, "clock-frequency", &clk_rate))
	clk_rate = 0;

	needs_vcc = of_property_read_bool(node, "vcc-supply");
	nop->gpiod_reset = devm_gpiod_get_optional(dev, "reset",
	GPIOD_ASIS);
	err = PTR_ERR_OR_ZERO(nop->gpiod_reset);
	if (!err) {
	nop->gpiod_vbus = devm_gpiod_get_optional(dev,
	"vbus-detect",
	GPIOD_ASIS);
	err = PTR_ERR_OR_ZERO(nop->gpiod_vbus);
	}
	} else if (pdata) {
	type = pdata->type;
	clk_rate = pdata->clk_rate;
	needs_vcc = pdata->needs_vcc;
	if (gpio_is_valid(pdata->gpio_reset)) {
	err = devm_gpio_request_one(dev, pdata->gpio_reset,
	GPIOF_ACTIVE_LOW,
	dev_name(dev));
	if (!err)
	nop->gpiod_reset =
	gpio_to_desc(pdata->gpio_reset);
	}
	nop->gpiod_vbus = pdata->gpiod_vbus;
	}

	if (err == -EPROBE_DEFER)
	return -EPROBE_DEFER;
	if (err) {
	dev_err(dev, "Error requesting RESET or VBUS GPIO\n");
	return err;
	}
	if (nop->gpiod_reset)
	gpiod_direction_output(nop->gpiod_reset, 1);

	nop->phy.otg = devm_kzalloc(dev, sizeof(*nop->phy.otg),
	GFP_KERNEL);
	if (!nop->phy.otg)
	return -ENOMEM;

	nop->clk = devm_clk_get(dev, "main_clk");
	if (IS_ERR(nop->clk)) {
	dev_dbg(dev, "Can't get phy clock: %ld\n",
	PTR_ERR(nop->clk));
	}

	if (!IS_ERR(nop->clk) && clk_rate) {
	err = clk_set_rate(nop->clk, clk_rate);
	if (err) {
	dev_err(dev, "Error setting clock rate\n");
	return err;
	}
	}

	nop->vcc = devm_regulator_get(dev, "vcc");
	if (IS_ERR(nop->vcc)) {
	dev_dbg(dev, "Error getting vcc regulator: %ld\n",
	PTR_ERR(nop->vcc));
	if (needs_vcc)
	return -EPROBE_DEFER;
	}

	nop->dev = dev;
	nop->phy.dev = nop->dev;
	nop->phy.label = "nop-xceiv";
	nop->phy.set_suspend = nop_set_suspend;
	nop->phy.type = type;

	nop->phy.otg->state = OTG_STATE_UNDEFINED;
	nop->phy.otg->usb_phy = &nop->phy;
	nop->phy.otg->set_host = nop_set_host;
	nop->phy.otg->set_peripheral = nop_set_peripheral;

	return 0;
	}
	EXPORT_SYMBOL_GPL(usb_phy_gen_create_phy);

	static int usb_phy_generic_probe(struct platform_device *pdev)
	{
	struct device *dev = &pdev->dev;
	struct usb_phy_generic *nop;
	int err;

	nop = devm_kzalloc(dev, sizeof(*nop), GFP_KERNEL);
	if (!nop)
	return -ENOMEM;

	err = usb_phy_gen_create_phy(dev, nop, dev_get_platdata(&pdev->dev));
	if (err)
	return err;
	if (nop->gpiod_vbus) {
	err = devm_request_threaded_irq(&pdev->dev,
	gpiod_to_irq(nop->gpiod_vbus),
	NULL, nop_gpio_vbus_thread,
	VBUS_IRQ_FLAGS, "vbus_detect",
	nop);
	if (err) {
	dev_err(&pdev->dev, "can't request irq %i, err: %d\n",
	gpiod_to_irq(nop->gpiod_vbus), err);
	return err;
	}
	}

	nop->phy.init = usb_gen_phy_init;
	nop->phy.shutdown = usb_gen_phy_shutdown;

	err = usb_add_phy_dev(&nop->phy);
	if (err) {
	dev_err(&pdev->dev, "can't register transceiver, err: %d\n",
	err);
	return err;
	}

	platform_set_drvdata(pdev, nop);

	return 0;
	}

	static int usb_phy_generic_remove(struct platform_device *pdev)
	{
	struct usb_phy_generic *nop = platform_get_drvdata(pdev);

	usb_remove_phy(&nop->phy);

	return 0;
	}

	static const struct of_device_id nop_xceiv_dt_ids[] = {
	{ .compatible = "usb-nop-xceiv" },
	{ }
	};

	MODULE_DEVICE_TABLE(of, nop_xceiv_dt_ids);

	static struct platform_driver usb_phy_generic_driver = {
	.probe = usb_phy_generic_probe,
	.remove = usb_phy_generic_remove,
	.driver = {
	.name = "usb_phy_generic",
	.of_match_table = nop_xceiv_dt_ids,
	},
	};

	static int __init usb_phy_generic_init(void)
	{
	return platform_driver_register(&usb_phy_generic_driver);
	}
	subsys_initcall(usb_phy_generic_init);

	static void __exit usb_phy_generic_exit(void)
	{
	platform_driver_unregister(&usb_phy_generic_driver);
	}
	module_exit(usb_phy_generic_exit);

	MODULE_ALIAS("platform:usb_phy_generic");
	MODULE_AUTHOR("Texas Instruments Inc");
	MODULE_DESCRIPTION("NOP USB Transceiver driver");
	MODULE_LICENSE("GPL");