diff options
Diffstat (limited to 'drivers/usb/phy/phy-generic.c')
| -rw-r--r-- | drivers/usb/phy/phy-generic.c | 309 | 
1 files changed, 309 insertions, 0 deletions
diff --git a/drivers/usb/phy/phy-generic.c b/drivers/usb/phy/phy-generic.c new file mode 100644 index 00000000000..7594e5069ae --- /dev/null +++ b/drivers/usb/phy/phy-generic.c @@ -0,0 +1,309 @@ +/* + * drivers/usb/otg/nop-usb-xceiv.c + * + * 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/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" + +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_set(struct usb_phy_generic *nop, int asserted) +{ +	int value; + +	if (!gpio_is_valid(nop->gpio_reset)) +		return; + +	value = asserted; +	if (nop->reset_active_low) +		value = !value; + +	gpio_set_value_cansleep(nop->gpio_reset, value); + +	if (!asserted) +		usleep_range(10000, 20000); +} + +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); + +	/* De-assert RESET */ +	nop_reset_set(nop, 0); + +	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); + +	/* Assert RESET */ +	nop_reset_set(nop, 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->phy->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; + +	u32 clk_rate = 0; +	bool needs_vcc = false; + +	nop->reset_active_low = true;	/* default behaviour */ + +	if (dev->of_node) { +		struct device_node *node = dev->of_node; +		enum of_gpio_flags flags = 0; + +		if (of_property_read_u32(node, "clock-frequency", &clk_rate)) +			clk_rate = 0; + +		needs_vcc = of_property_read_bool(node, "vcc-supply"); +		nop->gpio_reset = of_get_named_gpio_flags(node, "reset-gpios", +								0, &flags); +		if (nop->gpio_reset == -EPROBE_DEFER) +			return -EPROBE_DEFER; + +		nop->reset_active_low = flags & OF_GPIO_ACTIVE_LOW; + +	} else if (pdata) { +		type = pdata->type; +		clk_rate = pdata->clk_rate; +		needs_vcc = pdata->needs_vcc; +		nop->gpio_reset = pdata->gpio_reset; +	} else { +		nop->gpio_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; +	} + +	if (gpio_is_valid(nop->gpio_reset)) { +		unsigned long gpio_flags; + +		/* Assert RESET */ +		if (nop->reset_active_low) +			gpio_flags = GPIOF_OUT_INIT_LOW; +		else +			gpio_flags = GPIOF_OUT_INIT_HIGH; + +		err = devm_gpio_request_one(dev, nop->gpio_reset, +						gpio_flags, dev_name(dev)); +		if (err) { +			dev_err(dev, "Error requesting RESET GPIO %d\n", +					nop->gpio_reset); +			return err; +		} +	} + +	nop->dev		= dev; +	nop->phy.dev		= nop->dev; +	nop->phy.label		= "nop-xceiv"; +	nop->phy.set_suspend	= nop_set_suspend; +	nop->phy.state		= OTG_STATE_UNDEFINED; +	nop->phy.type		= type; + +	nop->phy.otg->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; + +	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", +		.owner	= THIS_MODULE, +		.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");  | 
