xref: /openbmc/linux/drivers/phy/ti/phy-omap-usb2.c (revision a2818ee4)
1 /*
2  * omap-usb2.c - USB PHY, talking to musb controller in OMAP.
3  *
4  * Copyright (C) 2012 Texas Instruments Incorporated - http://www.ti.com
5  * This program is free software; you can redistribute it and/or modify
6  * it under the terms of the GNU General Public License as published by
7  * the Free Software Foundation; either version 2 of the License, or
8  * (at your option) any later version.
9  *
10  * Author: Kishon Vijay Abraham I <kishon@ti.com>
11  *
12  * This program is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15  * GNU General Public License for more details.
16  *
17  */
18 
19 #include <linux/module.h>
20 #include <linux/platform_device.h>
21 #include <linux/slab.h>
22 #include <linux/of.h>
23 #include <linux/io.h>
24 #include <linux/phy/omap_usb.h>
25 #include <linux/usb/phy_companion.h>
26 #include <linux/clk.h>
27 #include <linux/err.h>
28 #include <linux/pm_runtime.h>
29 #include <linux/delay.h>
30 #include <linux/phy/omap_control_phy.h>
31 #include <linux/phy/phy.h>
32 #include <linux/mfd/syscon.h>
33 #include <linux/regmap.h>
34 #include <linux/of_platform.h>
35 
36 #define USB2PHY_DISCON_BYP_LATCH (1 << 31)
37 #define USB2PHY_ANA_CONFIG1 0x4c
38 
39 /**
40  * omap_usb2_set_comparator - links the comparator present in the sytem with
41  *	this phy
42  * @comparator - the companion phy(comparator) for this phy
43  *
44  * The phy companion driver should call this API passing the phy_companion
45  * filled with set_vbus and start_srp to be used by usb phy.
46  *
47  * For use by phy companion driver
48  */
49 int omap_usb2_set_comparator(struct phy_companion *comparator)
50 {
51 	struct omap_usb	*phy;
52 	struct usb_phy	*x = usb_get_phy(USB_PHY_TYPE_USB2);
53 
54 	if (IS_ERR(x))
55 		return -ENODEV;
56 
57 	phy = phy_to_omapusb(x);
58 	phy->comparator = comparator;
59 	return 0;
60 }
61 EXPORT_SYMBOL_GPL(omap_usb2_set_comparator);
62 
63 static int omap_usb_set_vbus(struct usb_otg *otg, bool enabled)
64 {
65 	struct omap_usb *phy = phy_to_omapusb(otg->usb_phy);
66 
67 	if (!phy->comparator)
68 		return -ENODEV;
69 
70 	return phy->comparator->set_vbus(phy->comparator, enabled);
71 }
72 
73 static int omap_usb_start_srp(struct usb_otg *otg)
74 {
75 	struct omap_usb *phy = phy_to_omapusb(otg->usb_phy);
76 
77 	if (!phy->comparator)
78 		return -ENODEV;
79 
80 	return phy->comparator->start_srp(phy->comparator);
81 }
82 
83 static int omap_usb_set_host(struct usb_otg *otg, struct usb_bus *host)
84 {
85 	otg->host = host;
86 	if (!host)
87 		otg->state = OTG_STATE_UNDEFINED;
88 
89 	return 0;
90 }
91 
92 static int omap_usb_set_peripheral(struct usb_otg *otg,
93 		struct usb_gadget *gadget)
94 {
95 	otg->gadget = gadget;
96 	if (!gadget)
97 		otg->state = OTG_STATE_UNDEFINED;
98 
99 	return 0;
100 }
101 
102 static int omap_usb_phy_power(struct omap_usb *phy, int on)
103 {
104 	u32 val;
105 	int ret;
106 
107 	if (!phy->syscon_phy_power) {
108 		omap_control_phy_power(phy->control_dev, on);
109 		return 0;
110 	}
111 
112 	if (on)
113 		val = phy->power_on;
114 	else
115 		val = phy->power_off;
116 
117 	ret = regmap_update_bits(phy->syscon_phy_power, phy->power_reg,
118 				 phy->mask, val);
119 	return ret;
120 }
121 
122 static int omap_usb_power_off(struct phy *x)
123 {
124 	struct omap_usb *phy = phy_get_drvdata(x);
125 
126 	return omap_usb_phy_power(phy, false);
127 }
128 
129 static int omap_usb_power_on(struct phy *x)
130 {
131 	struct omap_usb *phy = phy_get_drvdata(x);
132 
133 	return omap_usb_phy_power(phy, true);
134 }
135 
136 static int omap_usb2_disable_clocks(struct omap_usb *phy)
137 {
138 	clk_disable(phy->wkupclk);
139 	if (!IS_ERR(phy->optclk))
140 		clk_disable(phy->optclk);
141 
142 	return 0;
143 }
144 
145 static int omap_usb2_enable_clocks(struct omap_usb *phy)
146 {
147 	int ret;
148 
149 	ret = clk_enable(phy->wkupclk);
150 	if (ret < 0) {
151 		dev_err(phy->dev, "Failed to enable wkupclk %d\n", ret);
152 		goto err0;
153 	}
154 
155 	if (!IS_ERR(phy->optclk)) {
156 		ret = clk_enable(phy->optclk);
157 		if (ret < 0) {
158 			dev_err(phy->dev, "Failed to enable optclk %d\n", ret);
159 			goto err1;
160 		}
161 	}
162 
163 	return 0;
164 
165 err1:
166 	clk_disable(phy->wkupclk);
167 
168 err0:
169 	return ret;
170 }
171 
172 static int omap_usb_init(struct phy *x)
173 {
174 	struct omap_usb *phy = phy_get_drvdata(x);
175 	u32 val;
176 
177 	omap_usb2_enable_clocks(phy);
178 
179 	if (phy->flags & OMAP_USB2_CALIBRATE_FALSE_DISCONNECT) {
180 		/*
181 		 *
182 		 * Reduce the sensitivity of internal PHY by enabling the
183 		 * DISCON_BYP_LATCH of the USB2PHY_ANA_CONFIG1 register. This
184 		 * resolves issues with certain devices which can otherwise
185 		 * be prone to false disconnects.
186 		 *
187 		 */
188 		val = omap_usb_readl(phy->phy_base, USB2PHY_ANA_CONFIG1);
189 		val |= USB2PHY_DISCON_BYP_LATCH;
190 		omap_usb_writel(phy->phy_base, USB2PHY_ANA_CONFIG1, val);
191 	}
192 
193 	return 0;
194 }
195 
196 static int omap_usb_exit(struct phy *x)
197 {
198 	struct omap_usb *phy = phy_get_drvdata(x);
199 
200 	return omap_usb2_disable_clocks(phy);
201 }
202 
203 static const struct phy_ops ops = {
204 	.init		= omap_usb_init,
205 	.exit		= omap_usb_exit,
206 	.power_on	= omap_usb_power_on,
207 	.power_off	= omap_usb_power_off,
208 	.owner		= THIS_MODULE,
209 };
210 
211 static const struct usb_phy_data omap_usb2_data = {
212 	.label = "omap_usb2",
213 	.flags = OMAP_USB2_HAS_START_SRP | OMAP_USB2_HAS_SET_VBUS,
214 	.mask = OMAP_DEV_PHY_PD,
215 	.power_off = OMAP_DEV_PHY_PD,
216 };
217 
218 static const struct usb_phy_data omap5_usb2_data = {
219 	.label = "omap5_usb2",
220 	.flags = 0,
221 	.mask = OMAP_DEV_PHY_PD,
222 	.power_off = OMAP_DEV_PHY_PD,
223 };
224 
225 static const struct usb_phy_data dra7x_usb2_data = {
226 	.label = "dra7x_usb2",
227 	.flags = OMAP_USB2_CALIBRATE_FALSE_DISCONNECT,
228 	.mask = OMAP_DEV_PHY_PD,
229 	.power_off = OMAP_DEV_PHY_PD,
230 };
231 
232 static const struct usb_phy_data dra7x_usb2_phy2_data = {
233 	.label = "dra7x_usb2_phy2",
234 	.flags = OMAP_USB2_CALIBRATE_FALSE_DISCONNECT,
235 	.mask = OMAP_USB2_PHY_PD,
236 	.power_off = OMAP_USB2_PHY_PD,
237 };
238 
239 static const struct usb_phy_data am437x_usb2_data = {
240 	.label = "am437x_usb2",
241 	.flags =  0,
242 	.mask = AM437X_USB2_PHY_PD | AM437X_USB2_OTG_PD |
243 		AM437X_USB2_OTGVDET_EN | AM437X_USB2_OTGSESSEND_EN,
244 	.power_on = AM437X_USB2_OTGVDET_EN | AM437X_USB2_OTGSESSEND_EN,
245 	.power_off = AM437X_USB2_PHY_PD | AM437X_USB2_OTG_PD,
246 };
247 
248 static const struct of_device_id omap_usb2_id_table[] = {
249 	{
250 		.compatible = "ti,omap-usb2",
251 		.data = &omap_usb2_data,
252 	},
253 	{
254 		.compatible = "ti,omap5-usb2",
255 		.data = &omap5_usb2_data,
256 	},
257 	{
258 		.compatible = "ti,dra7x-usb2",
259 		.data = &dra7x_usb2_data,
260 	},
261 	{
262 		.compatible = "ti,dra7x-usb2-phy2",
263 		.data = &dra7x_usb2_phy2_data,
264 	},
265 	{
266 		.compatible = "ti,am437x-usb2",
267 		.data = &am437x_usb2_data,
268 	},
269 	{},
270 };
271 MODULE_DEVICE_TABLE(of, omap_usb2_id_table);
272 
273 static int omap_usb2_probe(struct platform_device *pdev)
274 {
275 	struct omap_usb	*phy;
276 	struct phy *generic_phy;
277 	struct resource *res;
278 	struct phy_provider *phy_provider;
279 	struct usb_otg *otg;
280 	struct device_node *node = pdev->dev.of_node;
281 	struct device_node *control_node;
282 	struct platform_device *control_pdev;
283 	const struct of_device_id *of_id;
284 	struct usb_phy_data *phy_data;
285 
286 	of_id = of_match_device(omap_usb2_id_table, &pdev->dev);
287 
288 	if (!of_id)
289 		return -EINVAL;
290 
291 	phy_data = (struct usb_phy_data *)of_id->data;
292 
293 	phy = devm_kzalloc(&pdev->dev, sizeof(*phy), GFP_KERNEL);
294 	if (!phy)
295 		return -ENOMEM;
296 
297 	otg = devm_kzalloc(&pdev->dev, sizeof(*otg), GFP_KERNEL);
298 	if (!otg)
299 		return -ENOMEM;
300 
301 	phy->dev		= &pdev->dev;
302 
303 	phy->phy.dev		= phy->dev;
304 	phy->phy.label		= phy_data->label;
305 	phy->phy.otg		= otg;
306 	phy->phy.type		= USB_PHY_TYPE_USB2;
307 	phy->mask		= phy_data->mask;
308 	phy->power_on		= phy_data->power_on;
309 	phy->power_off		= phy_data->power_off;
310 
311 	if (phy_data->flags & OMAP_USB2_CALIBRATE_FALSE_DISCONNECT) {
312 		res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
313 		phy->phy_base = devm_ioremap_resource(&pdev->dev, res);
314 		if (IS_ERR(phy->phy_base))
315 			return PTR_ERR(phy->phy_base);
316 		phy->flags |= OMAP_USB2_CALIBRATE_FALSE_DISCONNECT;
317 	}
318 
319 	phy->syscon_phy_power = syscon_regmap_lookup_by_phandle(node,
320 							"syscon-phy-power");
321 	if (IS_ERR(phy->syscon_phy_power)) {
322 		dev_dbg(&pdev->dev,
323 			"can't get syscon-phy-power, using control device\n");
324 		phy->syscon_phy_power = NULL;
325 
326 		control_node = of_parse_phandle(node, "ctrl-module", 0);
327 		if (!control_node) {
328 			dev_err(&pdev->dev,
329 				"Failed to get control device phandle\n");
330 			return -EINVAL;
331 		}
332 
333 		control_pdev = of_find_device_by_node(control_node);
334 		if (!control_pdev) {
335 			dev_err(&pdev->dev, "Failed to get control device\n");
336 			return -EINVAL;
337 		}
338 		phy->control_dev = &control_pdev->dev;
339 	} else {
340 		if (of_property_read_u32_index(node,
341 					       "syscon-phy-power", 1,
342 					       &phy->power_reg)) {
343 			dev_err(&pdev->dev,
344 				"couldn't get power reg. offset\n");
345 			return -EINVAL;
346 		}
347 	}
348 
349 	otg->set_host		= omap_usb_set_host;
350 	otg->set_peripheral	= omap_usb_set_peripheral;
351 	if (phy_data->flags & OMAP_USB2_HAS_SET_VBUS)
352 		otg->set_vbus		= omap_usb_set_vbus;
353 	if (phy_data->flags & OMAP_USB2_HAS_START_SRP)
354 		otg->start_srp		= omap_usb_start_srp;
355 	otg->usb_phy		= &phy->phy;
356 
357 	platform_set_drvdata(pdev, phy);
358 	pm_runtime_enable(phy->dev);
359 
360 	generic_phy = devm_phy_create(phy->dev, NULL, &ops);
361 	if (IS_ERR(generic_phy)) {
362 		pm_runtime_disable(phy->dev);
363 		return PTR_ERR(generic_phy);
364 	}
365 
366 	phy_set_drvdata(generic_phy, phy);
367 	omap_usb_power_off(generic_phy);
368 
369 	phy_provider = devm_of_phy_provider_register(phy->dev,
370 			of_phy_simple_xlate);
371 	if (IS_ERR(phy_provider)) {
372 		pm_runtime_disable(phy->dev);
373 		return PTR_ERR(phy_provider);
374 	}
375 
376 	phy->wkupclk = devm_clk_get(phy->dev, "wkupclk");
377 	if (IS_ERR(phy->wkupclk)) {
378 		dev_warn(&pdev->dev, "unable to get wkupclk, trying old name\n");
379 		phy->wkupclk = devm_clk_get(phy->dev, "usb_phy_cm_clk32k");
380 		if (IS_ERR(phy->wkupclk)) {
381 			dev_err(&pdev->dev, "unable to get usb_phy_cm_clk32k\n");
382 			pm_runtime_disable(phy->dev);
383 			return PTR_ERR(phy->wkupclk);
384 		} else {
385 			dev_warn(&pdev->dev,
386 				 "found usb_phy_cm_clk32k, please fix DTS\n");
387 		}
388 	}
389 	clk_prepare(phy->wkupclk);
390 
391 	phy->optclk = devm_clk_get(phy->dev, "refclk");
392 	if (IS_ERR(phy->optclk)) {
393 		dev_dbg(&pdev->dev, "unable to get refclk, trying old name\n");
394 		phy->optclk = devm_clk_get(phy->dev, "usb_otg_ss_refclk960m");
395 		if (IS_ERR(phy->optclk)) {
396 			dev_dbg(&pdev->dev,
397 				"unable to get usb_otg_ss_refclk960m\n");
398 		} else {
399 			dev_warn(&pdev->dev,
400 				 "found usb_otg_ss_refclk960m, please fix DTS\n");
401 		}
402 	}
403 
404 	if (!IS_ERR(phy->optclk))
405 		clk_prepare(phy->optclk);
406 
407 	usb_add_phy_dev(&phy->phy);
408 
409 	return 0;
410 }
411 
412 static int omap_usb2_remove(struct platform_device *pdev)
413 {
414 	struct omap_usb	*phy = platform_get_drvdata(pdev);
415 
416 	clk_unprepare(phy->wkupclk);
417 	if (!IS_ERR(phy->optclk))
418 		clk_unprepare(phy->optclk);
419 	usb_remove_phy(&phy->phy);
420 	pm_runtime_disable(phy->dev);
421 
422 	return 0;
423 }
424 
425 static struct platform_driver omap_usb2_driver = {
426 	.probe		= omap_usb2_probe,
427 	.remove		= omap_usb2_remove,
428 	.driver		= {
429 		.name	= "omap-usb2",
430 		.of_match_table = omap_usb2_id_table,
431 	},
432 };
433 
434 module_platform_driver(omap_usb2_driver);
435 
436 MODULE_ALIAS("platform:omap_usb2");
437 MODULE_AUTHOR("Texas Instruments Inc.");
438 MODULE_DESCRIPTION("OMAP USB2 phy driver");
439 MODULE_LICENSE("GPL v2");
440