2 * drivers/usb/otg/nop-usb-xceiv.c
4 * NOP USB transceiver for all USB transceiver which are either built-in
5 * into USB IP or which are mostly autonomous.
7 * Copyright (C) 2009 Texas Instruments Inc
8 * Author: Ajay Kumar Gupta <ajay.gupta@ti.com>
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License as published by
12 * the Free Software Foundation; either version 2 of the License, or
13 * (at your option) any later version.
15 * This program is distributed in the hope that it will be useful,
16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 * GNU General Public License for more details.
20 * You should have received a copy of the GNU General Public License
21 * along with this program; if not, write to the Free Software
22 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
25 * This provides a "nop" transceiver for PHYs which are
26 * autonomous such as isp1504, isp1707, etc.
29 #include <linux/module.h>
30 #include <linux/platform_device.h>
31 #include <linux/dma-mapping.h>
32 #include <linux/usb/otg.h>
33 #include <linux/usb/usb_phy_gen_xceiv.h>
34 #include <linux/slab.h>
35 #include <linux/clk.h>
36 #include <linux/regulator/consumer.h>
38 #include <linux/of_gpio.h>
39 #include <linux/gpio.h>
40 #include <linux/delay.h>
42 #include "phy-generic.h"
44 static struct platform_device *pd;
46 void usb_nop_xceiv_register(void)
50 pd = platform_device_register_simple("usb_phy_gen_xceiv", -1, NULL, 0);
52 pr_err("Unable to register generic usb transceiver\n");
56 EXPORT_SYMBOL(usb_nop_xceiv_register);
58 void usb_nop_xceiv_unregister(void)
60 platform_device_unregister(pd);
63 EXPORT_SYMBOL(usb_nop_xceiv_unregister);
65 static int nop_set_suspend(struct usb_phy *x, int suspend)
70 static void nop_reset_set(struct usb_phy_gen_xceiv *nop, int asserted)
74 if (!gpio_is_valid(nop->gpio_reset))
78 if (nop->reset_active_low)
81 gpio_set_value_cansleep(nop->gpio_reset, value);
84 usleep_range(10000, 20000);
87 int usb_gen_phy_init(struct usb_phy *phy)
89 struct usb_phy_gen_xceiv *nop = dev_get_drvdata(phy->dev);
91 if (!IS_ERR(nop->vcc)) {
92 if (regulator_enable(nop->vcc))
93 dev_err(phy->dev, "Failed to enable power\n");
96 if (!IS_ERR(nop->clk))
97 clk_prepare_enable(nop->clk);
100 nop_reset_set(nop, 0);
104 EXPORT_SYMBOL_GPL(usb_gen_phy_init);
106 void usb_gen_phy_shutdown(struct usb_phy *phy)
108 struct usb_phy_gen_xceiv *nop = dev_get_drvdata(phy->dev);
111 nop_reset_set(nop, 1);
113 if (!IS_ERR(nop->clk))
114 clk_disable_unprepare(nop->clk);
116 if (!IS_ERR(nop->vcc)) {
117 if (regulator_disable(nop->vcc))
118 dev_err(phy->dev, "Failed to disable power\n");
121 EXPORT_SYMBOL_GPL(usb_gen_phy_shutdown);
123 static int nop_set_peripheral(struct usb_otg *otg, struct usb_gadget *gadget)
133 otg->gadget = gadget;
134 otg->phy->state = OTG_STATE_B_IDLE;
138 static int nop_set_host(struct usb_otg *otg, struct usb_bus *host)
152 int usb_phy_gen_create_phy(struct device *dev, struct usb_phy_gen_xceiv *nop,
153 enum usb_phy_type type, u32 clk_rate, bool needs_vcc)
157 nop->phy.otg = devm_kzalloc(dev, sizeof(*nop->phy.otg),
162 nop->clk = devm_clk_get(dev, "main_clk");
163 if (IS_ERR(nop->clk)) {
164 dev_dbg(dev, "Can't get phy clock: %ld\n",
168 if (!IS_ERR(nop->clk) && clk_rate) {
169 err = clk_set_rate(nop->clk, clk_rate);
171 dev_err(dev, "Error setting clock rate\n");
176 nop->vcc = devm_regulator_get(dev, "vcc");
177 if (IS_ERR(nop->vcc)) {
178 dev_dbg(dev, "Error getting vcc regulator: %ld\n",
181 return -EPROBE_DEFER;
184 if (gpio_is_valid(nop->gpio_reset)) {
185 unsigned long gpio_flags;
188 if (nop->reset_active_low)
189 gpio_flags = GPIOF_OUT_INIT_LOW;
191 gpio_flags = GPIOF_OUT_INIT_HIGH;
193 err = devm_gpio_request_one(dev, nop->gpio_reset,
194 gpio_flags, dev_name(dev));
196 dev_err(dev, "Error requesting RESET GPIO %d\n",
203 nop->phy.dev = nop->dev;
204 nop->phy.label = "nop-xceiv";
205 nop->phy.set_suspend = nop_set_suspend;
206 nop->phy.state = OTG_STATE_UNDEFINED;
207 nop->phy.type = type;
209 nop->phy.otg->phy = &nop->phy;
210 nop->phy.otg->set_host = nop_set_host;
211 nop->phy.otg->set_peripheral = nop_set_peripheral;
213 ATOMIC_INIT_NOTIFIER_HEAD(&nop->phy.notifier);
216 EXPORT_SYMBOL_GPL(usb_phy_gen_create_phy);
218 static int usb_phy_gen_xceiv_probe(struct platform_device *pdev)
220 struct device *dev = &pdev->dev;
221 struct usb_phy_gen_xceiv_platform_data *pdata =
222 dev_get_platdata(&pdev->dev);
223 struct usb_phy_gen_xceiv *nop;
224 enum usb_phy_type type = USB_PHY_TYPE_USB2;
227 bool needs_vcc = false;
229 nop = devm_kzalloc(dev, sizeof(*nop), GFP_KERNEL);
233 nop->reset_active_low = true; /* default behaviour */
236 struct device_node *node = dev->of_node;
237 enum of_gpio_flags flags;
239 if (of_property_read_u32(node, "clock-frequency", &clk_rate))
242 needs_vcc = of_property_read_bool(node, "vcc-supply");
243 nop->gpio_reset = of_get_named_gpio_flags(node, "reset-gpios",
245 if (nop->gpio_reset == -EPROBE_DEFER)
246 return -EPROBE_DEFER;
248 nop->reset_active_low = flags & OF_GPIO_ACTIVE_LOW;
252 clk_rate = pdata->clk_rate;
253 needs_vcc = pdata->needs_vcc;
254 nop->gpio_reset = pdata->gpio_reset;
257 err = usb_phy_gen_create_phy(dev, nop, type, clk_rate, needs_vcc);
261 nop->phy.init = usb_gen_phy_init;
262 nop->phy.shutdown = usb_gen_phy_shutdown;
264 err = usb_add_phy_dev(&nop->phy);
266 dev_err(&pdev->dev, "can't register transceiver, err: %d\n",
271 platform_set_drvdata(pdev, nop);
278 static int usb_phy_gen_xceiv_remove(struct platform_device *pdev)
280 struct usb_phy_gen_xceiv *nop = platform_get_drvdata(pdev);
282 usb_remove_phy(&nop->phy);
287 static const struct of_device_id nop_xceiv_dt_ids[] = {
288 { .compatible = "usb-nop-xceiv" },
292 MODULE_DEVICE_TABLE(of, nop_xceiv_dt_ids);
294 static struct platform_driver usb_phy_gen_xceiv_driver = {
295 .probe = usb_phy_gen_xceiv_probe,
296 .remove = usb_phy_gen_xceiv_remove,
298 .name = "usb_phy_gen_xceiv",
299 .owner = THIS_MODULE,
300 .of_match_table = nop_xceiv_dt_ids,
304 static int __init usb_phy_gen_xceiv_init(void)
306 return platform_driver_register(&usb_phy_gen_xceiv_driver);
308 subsys_initcall(usb_phy_gen_xceiv_init);
310 static void __exit usb_phy_gen_xceiv_exit(void)
312 platform_driver_unregister(&usb_phy_gen_xceiv_driver);
314 module_exit(usb_phy_gen_xceiv_exit);
316 MODULE_ALIAS("platform:usb_phy_gen_xceiv");
317 MODULE_AUTHOR("Texas Instruments Inc");
318 MODULE_DESCRIPTION("NOP USB Transceiver driver");
319 MODULE_LICENSE("GPL");