| // SPDX-License-Identifier: GPL-2.0+ |
| /* |
| * 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> |
| * |
| * 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/gpio/consumer.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) |
| { |
| struct usb_phy_generic *nop = dev_get_drvdata(x->dev); |
| |
| if (!IS_ERR(nop->clk)) { |
| if (suspend) |
| clk_disable_unprepare(nop->clk); |
| else |
| clk_prepare_enable(nop->clk); |
| } |
| |
| return 0; |
| } |
| |
| static void nop_reset(struct usb_phy_generic *nop) |
| { |
| if (!nop->gpiod_reset) |
| return; |
| |
| gpiod_set_value_cansleep(nop->gpiod_reset, 1); |
| usleep_range(10000, 20000); |
| gpiod_set_value_cansleep(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; |
| |
| /* 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); |
| |
| 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); |
| int ret; |
| |
| if (!IS_ERR(nop->vcc)) { |
| if (regulator_enable(nop->vcc)) |
| dev_err(phy->dev, "Failed to enable power\n"); |
| } |
| |
| if (!IS_ERR(nop->clk)) { |
| ret = clk_prepare_enable(nop->clk); |
| if (ret) |
| return ret; |
| } |
| |
| 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_cansleep(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; |
| if (otg->state == OTG_STATE_B_PERIPHERAL) |
| atomic_notifier_call_chain(&otg->usb_phy->notifier, |
| USB_EVENT_VBUS, otg->gadget); |
| else |
| 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) |
| { |
| enum usb_phy_type type = USB_PHY_TYPE_USB2; |
| int err = 0; |
| |
| u32 clk_rate = 0; |
| bool needs_vcc = false, needs_clk = 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"); |
| needs_clk = of_property_read_bool(node, "clocks"); |
| } |
| 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); |
| } |
| |
| 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 (needs_clk) |
| return 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); |
| 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.otg->state = gpiod_get_value(nop->gpiod_vbus) ? |
| OTG_STATE_B_PERIPHERAL : OTG_STATE_B_IDLE; |
| } |
| |
| 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"); |