xref: /openbmc/linux/drivers/usb/musb/ux500.c (revision 275876e2)
1 /*
2  * Copyright (C) 2010 ST-Ericsson AB
3  * Mian Yousaf Kaukab <mian.yousaf.kaukab@stericsson.com>
4  *
5  * Based on omap2430.c
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License as published by
9  * the Free Software Foundation; either version 2 of the License, or
10  * (at your option) any later version.
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  * You should have received a copy of the GNU General Public License
18  * along with this program; if not, write to the Free Software
19  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
20  */
21 
22 #include <linux/module.h>
23 #include <linux/kernel.h>
24 #include <linux/clk.h>
25 #include <linux/err.h>
26 #include <linux/io.h>
27 #include <linux/of.h>
28 #include <linux/platform_device.h>
29 #include <linux/usb/musb-ux500.h>
30 
31 #include "musb_core.h"
32 
33 static struct musb_hdrc_config ux500_musb_hdrc_config = {
34 	.multipoint	= true,
35 	.dyn_fifo	= true,
36 	.num_eps	= 16,
37 	.ram_bits	= 16,
38 };
39 
40 struct ux500_glue {
41 	struct device		*dev;
42 	struct platform_device	*musb;
43 	struct clk		*clk;
44 };
45 #define glue_to_musb(g)	platform_get_drvdata(g->musb)
46 
47 static void ux500_musb_set_vbus(struct musb *musb, int is_on)
48 {
49 	u8            devctl;
50 	unsigned long timeout = jiffies + msecs_to_jiffies(1000);
51 	/* HDRC controls CPEN, but beware current surges during device
52 	 * connect.  They can trigger transient overcurrent conditions
53 	 * that must be ignored.
54 	 */
55 
56 	devctl = musb_readb(musb->mregs, MUSB_DEVCTL);
57 
58 	if (is_on) {
59 		if (musb->xceiv->state == OTG_STATE_A_IDLE) {
60 			/* start the session */
61 			devctl |= MUSB_DEVCTL_SESSION;
62 			musb_writeb(musb->mregs, MUSB_DEVCTL, devctl);
63 			/*
64 			 * Wait for the musb to set as A device to enable the
65 			 * VBUS
66 			 */
67 			while (musb_readb(musb->mregs, MUSB_DEVCTL) & 0x80) {
68 
69 				if (time_after(jiffies, timeout)) {
70 					dev_err(musb->controller,
71 					"configured as A device timeout");
72 					break;
73 				}
74 			}
75 
76 		} else {
77 			musb->is_active = 1;
78 			musb->xceiv->otg->default_a = 1;
79 			musb->xceiv->state = OTG_STATE_A_WAIT_VRISE;
80 			devctl |= MUSB_DEVCTL_SESSION;
81 			MUSB_HST_MODE(musb);
82 		}
83 	} else {
84 		musb->is_active = 0;
85 
86 		/* NOTE: we're skipping A_WAIT_VFALL -> A_IDLE and jumping
87 		 * right to B_IDLE...
88 		 */
89 		musb->xceiv->otg->default_a = 0;
90 		devctl &= ~MUSB_DEVCTL_SESSION;
91 		MUSB_DEV_MODE(musb);
92 	}
93 	musb_writeb(musb->mregs, MUSB_DEVCTL, devctl);
94 
95 	/*
96 	 * Devctl values will be updated after vbus goes below
97 	 * session_valid. The time taken depends on the capacitance
98 	 * on VBUS line. The max discharge time can be upto 1 sec
99 	 * as per the spec. Typically on our platform, it is 200ms
100 	 */
101 	if (!is_on)
102 		mdelay(200);
103 
104 	dev_dbg(musb->controller, "VBUS %s, devctl %02x\n",
105 		usb_otg_state_string(musb->xceiv->state),
106 		musb_readb(musb->mregs, MUSB_DEVCTL));
107 }
108 
109 static int musb_otg_notifications(struct notifier_block *nb,
110 		unsigned long event, void *unused)
111 {
112 	struct musb *musb = container_of(nb, struct musb, nb);
113 
114 	dev_dbg(musb->controller, "musb_otg_notifications %ld %s\n",
115 			event, usb_otg_state_string(musb->xceiv->state));
116 
117 	switch (event) {
118 	case UX500_MUSB_ID:
119 		dev_dbg(musb->controller, "ID GND\n");
120 		ux500_musb_set_vbus(musb, 1);
121 		break;
122 	case UX500_MUSB_VBUS:
123 		dev_dbg(musb->controller, "VBUS Connect\n");
124 		break;
125 	case UX500_MUSB_NONE:
126 		dev_dbg(musb->controller, "VBUS Disconnect\n");
127 		if (is_host_active(musb))
128 			ux500_musb_set_vbus(musb, 0);
129 		else
130 			musb->xceiv->state = OTG_STATE_B_IDLE;
131 		break;
132 	default:
133 		dev_dbg(musb->controller, "ID float\n");
134 		return NOTIFY_DONE;
135 	}
136 	return NOTIFY_OK;
137 }
138 
139 static irqreturn_t ux500_musb_interrupt(int irq, void *__hci)
140 {
141 	unsigned long   flags;
142 	irqreturn_t     retval = IRQ_NONE;
143 	struct musb     *musb = __hci;
144 
145 	spin_lock_irqsave(&musb->lock, flags);
146 
147 	musb->int_usb = musb_readb(musb->mregs, MUSB_INTRUSB);
148 	musb->int_tx = musb_readw(musb->mregs, MUSB_INTRTX);
149 	musb->int_rx = musb_readw(musb->mregs, MUSB_INTRRX);
150 
151 	if (musb->int_usb || musb->int_tx || musb->int_rx)
152 		retval = musb_interrupt(musb);
153 
154 	spin_unlock_irqrestore(&musb->lock, flags);
155 
156 	return retval;
157 }
158 
159 static int ux500_musb_init(struct musb *musb)
160 {
161 	int status;
162 
163 	musb->xceiv = usb_get_phy(USB_PHY_TYPE_USB2);
164 	if (IS_ERR_OR_NULL(musb->xceiv)) {
165 		pr_err("HS USB OTG: no transceiver configured\n");
166 		return -EPROBE_DEFER;
167 	}
168 
169 	musb->nb.notifier_call = musb_otg_notifications;
170 	status = usb_register_notifier(musb->xceiv, &musb->nb);
171 	if (status < 0) {
172 		dev_dbg(musb->controller, "notification register failed\n");
173 		return status;
174 	}
175 
176 	musb->isr = ux500_musb_interrupt;
177 
178 	return 0;
179 }
180 
181 static int ux500_musb_exit(struct musb *musb)
182 {
183 	usb_unregister_notifier(musb->xceiv, &musb->nb);
184 
185 	usb_put_phy(musb->xceiv);
186 
187 	return 0;
188 }
189 
190 static const struct musb_platform_ops ux500_ops = {
191 	.init		= ux500_musb_init,
192 	.exit		= ux500_musb_exit,
193 
194 	.set_vbus	= ux500_musb_set_vbus,
195 };
196 
197 static struct musb_hdrc_platform_data *
198 ux500_of_probe(struct platform_device *pdev, struct device_node *np)
199 {
200 	struct musb_hdrc_platform_data *pdata;
201 	const char *mode;
202 	int strlen;
203 
204 	pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
205 	if (!pdata)
206 		return NULL;
207 
208 	mode = of_get_property(np, "dr_mode", &strlen);
209 	if (!mode) {
210 		dev_err(&pdev->dev, "No 'dr_mode' property found\n");
211 		return NULL;
212 	}
213 
214 	if (strlen > 0) {
215 		if (!strcmp(mode, "host"))
216 			pdata->mode = MUSB_HOST;
217 		if (!strcmp(mode, "otg"))
218 			pdata->mode = MUSB_OTG;
219 		if (!strcmp(mode, "peripheral"))
220 			pdata->mode = MUSB_PERIPHERAL;
221 	}
222 
223 	return pdata;
224 }
225 
226 static int ux500_probe(struct platform_device *pdev)
227 {
228 	struct resource musb_resources[2];
229 	struct musb_hdrc_platform_data	*pdata = dev_get_platdata(&pdev->dev);
230 	struct device_node		*np = pdev->dev.of_node;
231 	struct platform_device		*musb;
232 	struct ux500_glue		*glue;
233 	struct clk			*clk;
234 	int				ret = -ENOMEM;
235 
236 	if (!pdata) {
237 		if (np) {
238 			pdata = ux500_of_probe(pdev, np);
239 			if (!pdata)
240 				goto err0;
241 
242 			pdev->dev.platform_data = pdata;
243 		} else {
244 			dev_err(&pdev->dev, "no pdata or device tree found\n");
245 			goto err0;
246 		}
247 	}
248 
249 	glue = devm_kzalloc(&pdev->dev, sizeof(*glue), GFP_KERNEL);
250 	if (!glue) {
251 		dev_err(&pdev->dev, "failed to allocate glue context\n");
252 		goto err0;
253 	}
254 
255 	musb = platform_device_alloc("musb-hdrc", PLATFORM_DEVID_AUTO);
256 	if (!musb) {
257 		dev_err(&pdev->dev, "failed to allocate musb device\n");
258 		goto err0;
259 	}
260 
261 	clk = devm_clk_get(&pdev->dev, NULL);
262 	if (IS_ERR(clk)) {
263 		dev_err(&pdev->dev, "failed to get clock\n");
264 		ret = PTR_ERR(clk);
265 		goto err1;
266 	}
267 
268 	ret = clk_prepare_enable(clk);
269 	if (ret) {
270 		dev_err(&pdev->dev, "failed to enable clock\n");
271 		goto err1;
272 	}
273 
274 	musb->dev.parent		= &pdev->dev;
275 	musb->dev.dma_mask		= &pdev->dev.coherent_dma_mask;
276 	musb->dev.coherent_dma_mask	= pdev->dev.coherent_dma_mask;
277 
278 	glue->dev			= &pdev->dev;
279 	glue->musb			= musb;
280 	glue->clk			= clk;
281 
282 	pdata->platform_ops		= &ux500_ops;
283 	pdata->config 			= &ux500_musb_hdrc_config;
284 
285 	platform_set_drvdata(pdev, glue);
286 
287 	memset(musb_resources, 0x00, sizeof(*musb_resources) *
288 			ARRAY_SIZE(musb_resources));
289 
290 	musb_resources[0].name = pdev->resource[0].name;
291 	musb_resources[0].start = pdev->resource[0].start;
292 	musb_resources[0].end = pdev->resource[0].end;
293 	musb_resources[0].flags = pdev->resource[0].flags;
294 
295 	musb_resources[1].name = pdev->resource[1].name;
296 	musb_resources[1].start = pdev->resource[1].start;
297 	musb_resources[1].end = pdev->resource[1].end;
298 	musb_resources[1].flags = pdev->resource[1].flags;
299 
300 	ret = platform_device_add_resources(musb, musb_resources,
301 			ARRAY_SIZE(musb_resources));
302 	if (ret) {
303 		dev_err(&pdev->dev, "failed to add resources\n");
304 		goto err2;
305 	}
306 
307 	ret = platform_device_add_data(musb, pdata, sizeof(*pdata));
308 	if (ret) {
309 		dev_err(&pdev->dev, "failed to add platform_data\n");
310 		goto err2;
311 	}
312 
313 	ret = platform_device_add(musb);
314 	if (ret) {
315 		dev_err(&pdev->dev, "failed to register musb device\n");
316 		goto err2;
317 	}
318 
319 	return 0;
320 
321 err2:
322 	clk_disable_unprepare(clk);
323 
324 err1:
325 	platform_device_put(musb);
326 
327 err0:
328 	return ret;
329 }
330 
331 static int ux500_remove(struct platform_device *pdev)
332 {
333 	struct ux500_glue	*glue = platform_get_drvdata(pdev);
334 
335 	platform_device_unregister(glue->musb);
336 	clk_disable_unprepare(glue->clk);
337 
338 	return 0;
339 }
340 
341 #ifdef CONFIG_PM
342 static int ux500_suspend(struct device *dev)
343 {
344 	struct ux500_glue	*glue = dev_get_drvdata(dev);
345 	struct musb		*musb = glue_to_musb(glue);
346 
347 	usb_phy_set_suspend(musb->xceiv, 1);
348 	clk_disable_unprepare(glue->clk);
349 
350 	return 0;
351 }
352 
353 static int ux500_resume(struct device *dev)
354 {
355 	struct ux500_glue	*glue = dev_get_drvdata(dev);
356 	struct musb		*musb = glue_to_musb(glue);
357 	int			ret;
358 
359 	ret = clk_prepare_enable(glue->clk);
360 	if (ret) {
361 		dev_err(dev, "failed to enable clock\n");
362 		return ret;
363 	}
364 
365 	usb_phy_set_suspend(musb->xceiv, 0);
366 
367 	return 0;
368 }
369 #endif
370 
371 static SIMPLE_DEV_PM_OPS(ux500_pm_ops, ux500_suspend, ux500_resume);
372 
373 static const struct of_device_id ux500_match[] = {
374         { .compatible = "stericsson,db8500-musb", },
375         {}
376 };
377 
378 static struct platform_driver ux500_driver = {
379 	.probe		= ux500_probe,
380 	.remove		= ux500_remove,
381 	.driver		= {
382 		.name	= "musb-ux500",
383 		.pm	= &ux500_pm_ops,
384 		.of_match_table = ux500_match,
385 	},
386 };
387 
388 MODULE_DESCRIPTION("UX500 MUSB Glue Layer");
389 MODULE_AUTHOR("Mian Yousaf Kaukab <mian.yousaf.kaukab@stericsson.com>");
390 MODULE_LICENSE("GPL v2");
391 module_platform_driver(ux500_driver);
392