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"); |
