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/of_platform.h>
33
34#define USB2PHY_DISCON_BYP_LATCH (1 << 31)
35#define USB2PHY_ANA_CONFIG1 0x4c
36
37/**
38 * omap_usb2_set_comparator - links the comparator present in the sytem with
39 *	this phy
40 * @comparator - the companion phy(comparator) for this phy
41 *
42 * The phy companion driver should call this API passing the phy_companion
43 * filled with set_vbus and start_srp to be used by usb phy.
44 *
45 * For use by phy companion driver
46 */
47int omap_usb2_set_comparator(struct phy_companion *comparator)
48{
49	struct omap_usb	*phy;
50	struct usb_phy	*x = usb_get_phy(USB_PHY_TYPE_USB2);
51
52	if (IS_ERR(x))
53		return -ENODEV;
54
55	phy = phy_to_omapusb(x);
56	phy->comparator = comparator;
57	return 0;
58}
59EXPORT_SYMBOL_GPL(omap_usb2_set_comparator);
60
61static int omap_usb_set_vbus(struct usb_otg *otg, bool enabled)
62{
63	struct omap_usb *phy = phy_to_omapusb(otg->usb_phy);
64
65	if (!phy->comparator)
66		return -ENODEV;
67
68	return phy->comparator->set_vbus(phy->comparator, enabled);
69}
70
71static int omap_usb_start_srp(struct usb_otg *otg)
72{
73	struct omap_usb *phy = phy_to_omapusb(otg->usb_phy);
74
75	if (!phy->comparator)
76		return -ENODEV;
77
78	return phy->comparator->start_srp(phy->comparator);
79}
80
81static int omap_usb_set_host(struct usb_otg *otg, struct usb_bus *host)
82{
83	otg->host = host;
84	if (!host)
85		otg->state = OTG_STATE_UNDEFINED;
86
87	return 0;
88}
89
90static int omap_usb_set_peripheral(struct usb_otg *otg,
91		struct usb_gadget *gadget)
92{
93	otg->gadget = gadget;
94	if (!gadget)
95		otg->state = OTG_STATE_UNDEFINED;
96
97	return 0;
98}
99
100static int omap_usb_power_off(struct phy *x)
101{
102	struct omap_usb *phy = phy_get_drvdata(x);
103
104	omap_control_phy_power(phy->control_dev, 0);
105
106	return 0;
107}
108
109static int omap_usb_power_on(struct phy *x)
110{
111	struct omap_usb *phy = phy_get_drvdata(x);
112
113	omap_control_phy_power(phy->control_dev, 1);
114
115	return 0;
116}
117
118static int omap_usb_init(struct phy *x)
119{
120	struct omap_usb *phy = phy_get_drvdata(x);
121	u32 val;
122
123	if (phy->flags & OMAP_USB2_CALIBRATE_FALSE_DISCONNECT) {
124		/*
125		 *
126		 * Reduce the sensitivity of internal PHY by enabling the
127		 * DISCON_BYP_LATCH of the USB2PHY_ANA_CONFIG1 register. This
128		 * resolves issues with certain devices which can otherwise
129		 * be prone to false disconnects.
130		 *
131		 */
132		val = omap_usb_readl(phy->phy_base, USB2PHY_ANA_CONFIG1);
133		val |= USB2PHY_DISCON_BYP_LATCH;
134		omap_usb_writel(phy->phy_base, USB2PHY_ANA_CONFIG1, val);
135	}
136
137	return 0;
138}
139
140static const struct phy_ops ops = {
141	.init		= omap_usb_init,
142	.power_on	= omap_usb_power_on,
143	.power_off	= omap_usb_power_off,
144	.owner		= THIS_MODULE,
145};
146
147static const struct usb_phy_data omap_usb2_data = {
148	.label = "omap_usb2",
149	.flags = OMAP_USB2_HAS_START_SRP | OMAP_USB2_HAS_SET_VBUS,
150};
151
152static const struct usb_phy_data omap5_usb2_data = {
153	.label = "omap5_usb2",
154	.flags = 0,
155};
156
157static const struct usb_phy_data dra7x_usb2_data = {
158	.label = "dra7x_usb2",
159	.flags = OMAP_USB2_CALIBRATE_FALSE_DISCONNECT,
160};
161
162static const struct usb_phy_data am437x_usb2_data = {
163	.label = "am437x_usb2",
164	.flags =  0,
165};
166
167static const struct of_device_id omap_usb2_id_table[] = {
168	{
169		.compatible = "ti,omap-usb2",
170		.data = &omap_usb2_data,
171	},
172	{
173		.compatible = "ti,omap5-usb2",
174		.data = &omap5_usb2_data,
175	},
176	{
177		.compatible = "ti,dra7x-usb2",
178		.data = &dra7x_usb2_data,
179	},
180	{
181		.compatible = "ti,am437x-usb2",
182		.data = &am437x_usb2_data,
183	},
184	{},
185};
186MODULE_DEVICE_TABLE(of, omap_usb2_id_table);
187
188static int omap_usb2_probe(struct platform_device *pdev)
189{
190	struct omap_usb	*phy;
191	struct phy *generic_phy;
192	struct resource *res;
193	struct phy_provider *phy_provider;
194	struct usb_otg *otg;
195	struct device_node *node = pdev->dev.of_node;
196	struct device_node *control_node;
197	struct platform_device *control_pdev;
198	const struct of_device_id *of_id;
199	struct usb_phy_data *phy_data;
200
201	of_id = of_match_device(omap_usb2_id_table, &pdev->dev);
202
203	if (!of_id)
204		return -EINVAL;
205
206	phy_data = (struct usb_phy_data *)of_id->data;
207
208	phy = devm_kzalloc(&pdev->dev, sizeof(*phy), GFP_KERNEL);
209	if (!phy)
210		return -ENOMEM;
211
212	otg = devm_kzalloc(&pdev->dev, sizeof(*otg), GFP_KERNEL);
213	if (!otg)
214		return -ENOMEM;
215
216	phy->dev		= &pdev->dev;
217
218	phy->phy.dev		= phy->dev;
219	phy->phy.label		= phy_data->label;
220	phy->phy.otg		= otg;
221	phy->phy.type		= USB_PHY_TYPE_USB2;
222
223	if (phy_data->flags & OMAP_USB2_CALIBRATE_FALSE_DISCONNECT) {
224		res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
225		phy->phy_base = devm_ioremap_resource(&pdev->dev, res);
226		if (IS_ERR(phy->phy_base))
227			return PTR_ERR(phy->phy_base);
228		phy->flags |= OMAP_USB2_CALIBRATE_FALSE_DISCONNECT;
229	}
230
231	control_node = of_parse_phandle(node, "ctrl-module", 0);
232	if (!control_node) {
233		dev_err(&pdev->dev, "Failed to get control device phandle\n");
234		return -EINVAL;
235	}
236
237	control_pdev = of_find_device_by_node(control_node);
238	if (!control_pdev) {
239		dev_err(&pdev->dev, "Failed to get control device\n");
240		return -EINVAL;
241	}
242
243	phy->control_dev = &control_pdev->dev;
244	omap_control_phy_power(phy->control_dev, 0);
245
246	otg->set_host		= omap_usb_set_host;
247	otg->set_peripheral	= omap_usb_set_peripheral;
248	if (phy_data->flags & OMAP_USB2_HAS_SET_VBUS)
249		otg->set_vbus		= omap_usb_set_vbus;
250	if (phy_data->flags & OMAP_USB2_HAS_START_SRP)
251		otg->start_srp		= omap_usb_start_srp;
252	otg->usb_phy		= &phy->phy;
253
254	platform_set_drvdata(pdev, phy);
255	pm_runtime_enable(phy->dev);
256
257	generic_phy = devm_phy_create(phy->dev, NULL, &ops);
258	if (IS_ERR(generic_phy)) {
259		pm_runtime_disable(phy->dev);
260		return PTR_ERR(generic_phy);
261	}
262
263	phy_set_drvdata(generic_phy, phy);
264
265	phy_provider = devm_of_phy_provider_register(phy->dev,
266			of_phy_simple_xlate);
267	if (IS_ERR(phy_provider)) {
268		pm_runtime_disable(phy->dev);
269		return PTR_ERR(phy_provider);
270	}
271
272	phy->wkupclk = devm_clk_get(phy->dev, "wkupclk");
273	if (IS_ERR(phy->wkupclk)) {
274		dev_warn(&pdev->dev, "unable to get wkupclk, trying old name\n");
275		phy->wkupclk = devm_clk_get(phy->dev, "usb_phy_cm_clk32k");
276		if (IS_ERR(phy->wkupclk)) {
277			dev_err(&pdev->dev, "unable to get usb_phy_cm_clk32k\n");
278			pm_runtime_disable(phy->dev);
279			return PTR_ERR(phy->wkupclk);
280		} else {
281			dev_warn(&pdev->dev,
282				 "found usb_phy_cm_clk32k, please fix DTS\n");
283		}
284	}
285	clk_prepare(phy->wkupclk);
286
287	phy->optclk = devm_clk_get(phy->dev, "refclk");
288	if (IS_ERR(phy->optclk)) {
289		dev_dbg(&pdev->dev, "unable to get refclk, trying old name\n");
290		phy->optclk = devm_clk_get(phy->dev, "usb_otg_ss_refclk960m");
291		if (IS_ERR(phy->optclk)) {
292			dev_dbg(&pdev->dev,
293				"unable to get usb_otg_ss_refclk960m\n");
294		} else {
295			dev_warn(&pdev->dev,
296				 "found usb_otg_ss_refclk960m, please fix DTS\n");
297		}
298	}
299
300	if (!IS_ERR(phy->optclk))
301		clk_prepare(phy->optclk);
302
303	usb_add_phy_dev(&phy->phy);
304
305	return 0;
306}
307
308static int omap_usb2_remove(struct platform_device *pdev)
309{
310	struct omap_usb	*phy = platform_get_drvdata(pdev);
311
312	clk_unprepare(phy->wkupclk);
313	if (!IS_ERR(phy->optclk))
314		clk_unprepare(phy->optclk);
315	usb_remove_phy(&phy->phy);
316	pm_runtime_disable(phy->dev);
317
318	return 0;
319}
320
321#ifdef CONFIG_PM
322
323static int omap_usb2_runtime_suspend(struct device *dev)
324{
325	struct platform_device	*pdev = to_platform_device(dev);
326	struct omap_usb	*phy = platform_get_drvdata(pdev);
327
328	clk_disable(phy->wkupclk);
329	if (!IS_ERR(phy->optclk))
330		clk_disable(phy->optclk);
331
332	return 0;
333}
334
335static int omap_usb2_runtime_resume(struct device *dev)
336{
337	struct platform_device	*pdev = to_platform_device(dev);
338	struct omap_usb	*phy = platform_get_drvdata(pdev);
339	int ret;
340
341	ret = clk_enable(phy->wkupclk);
342	if (ret < 0) {
343		dev_err(phy->dev, "Failed to enable wkupclk %d\n", ret);
344		goto err0;
345	}
346
347	if (!IS_ERR(phy->optclk)) {
348		ret = clk_enable(phy->optclk);
349		if (ret < 0) {
350			dev_err(phy->dev, "Failed to enable optclk %d\n", ret);
351			goto err1;
352		}
353	}
354
355	return 0;
356
357err1:
358	clk_disable(phy->wkupclk);
359
360err0:
361	return ret;
362}
363
364static const struct dev_pm_ops omap_usb2_pm_ops = {
365	SET_RUNTIME_PM_OPS(omap_usb2_runtime_suspend, omap_usb2_runtime_resume,
366		NULL)
367};
368
369#define DEV_PM_OPS     (&omap_usb2_pm_ops)
370#else
371#define DEV_PM_OPS     NULL
372#endif
373
374static struct platform_driver omap_usb2_driver = {
375	.probe		= omap_usb2_probe,
376	.remove		= omap_usb2_remove,
377	.driver		= {
378		.name	= "omap-usb2",
379		.pm	= DEV_PM_OPS,
380		.of_match_table = omap_usb2_id_table,
381	},
382};
383
384module_platform_driver(omap_usb2_driver);
385
386MODULE_ALIAS("platform:omap_usb2");
387MODULE_AUTHOR("Texas Instruments Inc.");
388MODULE_DESCRIPTION("OMAP USB2 phy driver");
389MODULE_LICENSE("GPL v2");
390