1 // SPDX-License-Identifier: GPL-2.0+ 2 /* 3 * NOP USB transceiver for all USB transceiver which are either built-in 4 * into USB IP or which are mostly autonomous. 5 * 6 * Copyright (C) 2009 Texas Instruments Inc 7 * Author: Ajay Kumar Gupta <ajay.gupta@ti.com> 8 * 9 * Current status: 10 * This provides a "nop" transceiver for PHYs which are 11 * autonomous such as isp1504, isp1707, etc. 12 */ 13 14 #include <linux/module.h> 15 #include <linux/platform_device.h> 16 #include <linux/dma-mapping.h> 17 #include <linux/usb/gadget.h> 18 #include <linux/usb/otg.h> 19 #include <linux/usb/usb_phy_generic.h> 20 #include <linux/slab.h> 21 #include <linux/clk.h> 22 #include <linux/regulator/consumer.h> 23 #include <linux/property.h> 24 #include <linux/gpio/consumer.h> 25 #include <linux/delay.h> 26 27 #include "phy-generic.h" 28 29 #define VBUS_IRQ_FLAGS \ 30 (IRQF_SHARED | IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING | \ 31 IRQF_ONESHOT) 32 33 struct platform_device *usb_phy_generic_register(void) 34 { 35 return platform_device_register_simple("usb_phy_generic", 36 PLATFORM_DEVID_AUTO, NULL, 0); 37 } 38 EXPORT_SYMBOL_GPL(usb_phy_generic_register); 39 40 void usb_phy_generic_unregister(struct platform_device *pdev) 41 { 42 platform_device_unregister(pdev); 43 } 44 EXPORT_SYMBOL_GPL(usb_phy_generic_unregister); 45 46 static int nop_set_suspend(struct usb_phy *x, int suspend) 47 { 48 struct usb_phy_generic *nop = dev_get_drvdata(x->dev); 49 int ret = 0; 50 51 if (suspend) { 52 clk_disable_unprepare(nop->clk); 53 if (!IS_ERR(nop->vcc) && !device_may_wakeup(x->dev)) 54 ret = regulator_disable(nop->vcc); 55 } else { 56 if (!IS_ERR(nop->vcc) && !device_may_wakeup(x->dev)) 57 ret = regulator_enable(nop->vcc); 58 clk_prepare_enable(nop->clk); 59 } 60 61 return ret; 62 } 63 64 static void nop_reset(struct usb_phy_generic *nop) 65 { 66 if (!nop->gpiod_reset) 67 return; 68 69 gpiod_set_value_cansleep(nop->gpiod_reset, 1); 70 usleep_range(10000, 20000); 71 gpiod_set_value_cansleep(nop->gpiod_reset, 0); 72 usleep_range(10000, 30000); 73 } 74 75 /* interface to regulator framework */ 76 static int nop_set_vbus(struct usb_otg *otg, bool enable) 77 { 78 int ret = 0; 79 struct usb_phy_generic *nop = dev_get_drvdata(otg->usb_phy->dev); 80 81 if (!nop->vbus_draw) 82 return 0; 83 84 if (enable && !nop->vbus_draw_enabled) { 85 ret = regulator_enable(nop->vbus_draw); 86 if (ret) 87 nop->vbus_draw_enabled = false; 88 else 89 nop->vbus_draw_enabled = true; 90 91 } else if (!enable && nop->vbus_draw_enabled) { 92 ret = regulator_disable(nop->vbus_draw); 93 nop->vbus_draw_enabled = false; 94 } 95 return ret; 96 } 97 98 99 static irqreturn_t nop_gpio_vbus_thread(int irq, void *data) 100 { 101 struct usb_phy_generic *nop = data; 102 struct usb_otg *otg = nop->phy.otg; 103 int vbus, status; 104 105 vbus = gpiod_get_value(nop->gpiod_vbus); 106 if ((vbus ^ nop->vbus) == 0) 107 return IRQ_HANDLED; 108 nop->vbus = vbus; 109 110 if (vbus) { 111 status = USB_EVENT_VBUS; 112 otg->state = OTG_STATE_B_PERIPHERAL; 113 nop->phy.last_event = status; 114 115 atomic_notifier_call_chain(&nop->phy.notifier, status, 116 otg->gadget); 117 } else { 118 status = USB_EVENT_NONE; 119 otg->state = OTG_STATE_B_IDLE; 120 nop->phy.last_event = status; 121 122 atomic_notifier_call_chain(&nop->phy.notifier, status, 123 otg->gadget); 124 } 125 return IRQ_HANDLED; 126 } 127 128 int usb_gen_phy_init(struct usb_phy *phy) 129 { 130 struct usb_phy_generic *nop = dev_get_drvdata(phy->dev); 131 int ret; 132 133 if (!IS_ERR(nop->vcc)) { 134 if (regulator_enable(nop->vcc)) 135 dev_err(phy->dev, "Failed to enable power\n"); 136 } 137 138 ret = clk_prepare_enable(nop->clk); 139 if (ret) 140 return ret; 141 142 nop_reset(nop); 143 144 return 0; 145 } 146 EXPORT_SYMBOL_GPL(usb_gen_phy_init); 147 148 void usb_gen_phy_shutdown(struct usb_phy *phy) 149 { 150 struct usb_phy_generic *nop = dev_get_drvdata(phy->dev); 151 152 gpiod_set_value_cansleep(nop->gpiod_reset, 1); 153 154 clk_disable_unprepare(nop->clk); 155 156 if (!IS_ERR(nop->vcc)) { 157 if (regulator_disable(nop->vcc)) 158 dev_err(phy->dev, "Failed to disable power\n"); 159 } 160 } 161 EXPORT_SYMBOL_GPL(usb_gen_phy_shutdown); 162 163 static int nop_set_peripheral(struct usb_otg *otg, struct usb_gadget *gadget) 164 { 165 if (!otg) 166 return -ENODEV; 167 168 if (!gadget) { 169 otg->gadget = NULL; 170 return -ENODEV; 171 } 172 173 otg->gadget = gadget; 174 if (otg->state == OTG_STATE_B_PERIPHERAL) 175 atomic_notifier_call_chain(&otg->usb_phy->notifier, 176 USB_EVENT_VBUS, otg->gadget); 177 else 178 otg->state = OTG_STATE_B_IDLE; 179 return 0; 180 } 181 182 static int nop_set_host(struct usb_otg *otg, struct usb_bus *host) 183 { 184 if (!otg) 185 return -ENODEV; 186 187 if (!host) { 188 otg->host = NULL; 189 return -ENODEV; 190 } 191 192 otg->host = host; 193 return 0; 194 } 195 196 int usb_phy_gen_create_phy(struct device *dev, struct usb_phy_generic *nop) 197 { 198 enum usb_phy_type type = USB_PHY_TYPE_USB2; 199 int err = 0; 200 u32 clk_rate = 0; 201 202 device_property_read_u32(dev, "clock-frequency", &clk_rate); 203 nop->gpiod_reset = devm_gpiod_get_optional(dev, "reset", 204 GPIOD_ASIS); 205 err = PTR_ERR_OR_ZERO(nop->gpiod_reset); 206 if (!err) { 207 nop->gpiod_vbus = devm_gpiod_get_optional(dev, 208 "vbus-detect", 209 GPIOD_ASIS); 210 err = PTR_ERR_OR_ZERO(nop->gpiod_vbus); 211 } 212 213 if (err) 214 return dev_err_probe(dev, err, 215 "Error requesting RESET or VBUS GPIO\n"); 216 if (nop->gpiod_reset) 217 gpiod_direction_output(nop->gpiod_reset, 1); 218 219 nop->phy.otg = devm_kzalloc_obj(dev, *nop->phy.otg); 220 if (!nop->phy.otg) 221 return -ENOMEM; 222 223 nop->clk = devm_clk_get_optional(dev, "main_clk"); 224 if (IS_ERR(nop->clk)) 225 return dev_err_probe(dev, PTR_ERR(nop->clk), 226 "Can't get phy clock\n"); 227 228 if (clk_rate) { 229 err = clk_set_rate(nop->clk, clk_rate); 230 if (err) 231 return dev_err_probe(dev, err, 232 "Error setting clock rate\n"); 233 } 234 235 nop->vcc = devm_regulator_get_optional(dev, "vcc"); 236 if (IS_ERR(nop->vcc) && PTR_ERR(nop->vcc) != -ENODEV) 237 return dev_err_probe(dev, PTR_ERR(nop->vcc), 238 "could not get vcc regulator\n"); 239 240 nop->vbus_draw = devm_regulator_get_exclusive(dev, "vbus"); 241 if (PTR_ERR(nop->vbus_draw) == -ENODEV) 242 nop->vbus_draw = NULL; 243 if (IS_ERR(nop->vbus_draw)) 244 return dev_err_probe(dev, PTR_ERR(nop->vbus_draw), 245 "could not get vbus regulator\n"); 246 247 nop->dev = dev; 248 nop->phy.dev = nop->dev; 249 nop->phy.label = "nop-xceiv"; 250 nop->phy.set_suspend = nop_set_suspend; 251 nop->phy.type = type; 252 253 nop->phy.otg->state = OTG_STATE_UNDEFINED; 254 nop->phy.otg->usb_phy = &nop->phy; 255 nop->phy.otg->set_host = nop_set_host; 256 nop->phy.otg->set_peripheral = nop_set_peripheral; 257 nop->phy.otg->set_vbus = nop_set_vbus; 258 259 return 0; 260 } 261 EXPORT_SYMBOL_GPL(usb_phy_gen_create_phy); 262 263 static int usb_phy_generic_probe(struct platform_device *pdev) 264 { 265 struct device *dev = &pdev->dev; 266 struct usb_phy_generic *nop; 267 int err; 268 269 nop = devm_kzalloc_obj(dev, *nop); 270 if (!nop) 271 return -ENOMEM; 272 273 err = usb_phy_gen_create_phy(dev, nop); 274 if (err) 275 return err; 276 277 if (nop->gpiod_vbus) { 278 err = devm_request_threaded_irq(dev, 279 gpiod_to_irq(nop->gpiod_vbus), 280 NULL, nop_gpio_vbus_thread, 281 VBUS_IRQ_FLAGS, "vbus_detect", 282 nop); 283 if (err) 284 return err; 285 286 nop->phy.otg->state = gpiod_get_value(nop->gpiod_vbus) ? 287 OTG_STATE_B_PERIPHERAL : OTG_STATE_B_IDLE; 288 } 289 290 nop->phy.init = usb_gen_phy_init; 291 nop->phy.shutdown = usb_gen_phy_shutdown; 292 293 err = usb_add_phy_dev(&nop->phy); 294 if (err) 295 return dev_err_probe(dev, err, "can't register transceiver\n"); 296 297 platform_set_drvdata(pdev, nop); 298 299 device_set_wakeup_capable(dev, 300 device_property_read_bool(dev, "wakeup-source")); 301 302 return 0; 303 } 304 305 static void usb_phy_generic_remove(struct platform_device *pdev) 306 { 307 struct usb_phy_generic *nop = platform_get_drvdata(pdev); 308 309 usb_remove_phy(&nop->phy); 310 311 if (nop->vbus_draw && nop->vbus_draw_enabled) 312 regulator_disable(nop->vbus_draw); 313 } 314 315 static const struct of_device_id nop_xceiv_dt_ids[] = { 316 { .compatible = "usb-nop-xceiv" }, 317 { } 318 }; 319 320 MODULE_DEVICE_TABLE(of, nop_xceiv_dt_ids); 321 322 static struct platform_driver usb_phy_generic_driver = { 323 .probe = usb_phy_generic_probe, 324 .remove = usb_phy_generic_remove, 325 .driver = { 326 .name = "usb_phy_generic", 327 .of_match_table = nop_xceiv_dt_ids, 328 }, 329 }; 330 331 static int __init usb_phy_generic_init(void) 332 { 333 return platform_driver_register(&usb_phy_generic_driver); 334 } 335 subsys_initcall(usb_phy_generic_init); 336 337 static void __exit usb_phy_generic_exit(void) 338 { 339 platform_driver_unregister(&usb_phy_generic_driver); 340 } 341 module_exit(usb_phy_generic_exit); 342 343 MODULE_ALIAS("platform:usb_phy_generic"); 344 MODULE_AUTHOR("Texas Instruments Inc"); 345 MODULE_DESCRIPTION("NOP USB Transceiver driver"); 346 MODULE_LICENSE("GPL"); 347