xref: /openbmc/linux/drivers/usb/musb/ux500.c (revision c4c11dd1) 
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/init.h>
25 #include <linux/clk.h>
26 #include <linux/err.h>
27 #include <linux/io.h>
28 #include <linux/of.h>
29 #include <linux/platform_device.h>
30 #include <linux/usb/musb-ux500.h>
31 
32 #include "musb_core.h"
33 
34 static struct musb_hdrc_config ux500_musb_hdrc_config = {
35 	.multipoint	= true,
36 	.dyn_fifo	= true,
37 	.num_eps	= 16,
38 	.ram_bits	= 16,
39 };
40 
41 struct ux500_glue {
42 	struct device		*dev;
43 	struct platform_device	*musb;
44 	struct clk		*clk;
45 };
46 #define glue_to_musb(g)	platform_get_drvdata(g->musb)
47 
48 static void ux500_musb_set_vbus(struct musb *musb, int is_on)
49 {
50 	u8            devctl;
51 	unsigned long timeout = jiffies + msecs_to_jiffies(1000);
52 	/* HDRC controls CPEN, but beware current surges during device
53 	 * connect.  They can trigger transient overcurrent conditions
54 	 * that must be ignored.
55 	 */
56 
57 	devctl = musb_readb(musb->mregs, MUSB_DEVCTL);
58 
59 	if (is_on) {
60 		if (musb->xceiv->state == OTG_STATE_A_IDLE) {
61 			/* start the session */
62 			devctl |= MUSB_DEVCTL_SESSION;
63 			musb_writeb(musb->mregs, MUSB_DEVCTL, devctl);
64 			/*
65 			 * Wait for the musb to set as A device to enable the
66 			 * VBUS
67 			 */
68 			while (musb_readb(musb->mregs, MUSB_DEVCTL) & 0x80) {
69 
70 				if (time_after(jiffies, timeout)) {
71 					dev_err(musb->controller,
72 					"configured as A device timeout");
73 					break;
74 				}
75 			}
76 
77 		} else {
78 			musb->is_active = 1;
79 			musb->xceiv->otg->default_a = 1;
80 			musb->xceiv->state = OTG_STATE_A_WAIT_VRISE;
81 			devctl |= MUSB_DEVCTL_SESSION;
82 			MUSB_HST_MODE(musb);
83 		}
84 	} else {
85 		musb->is_active = 0;
86 
87 		/* NOTE: we're skipping A_WAIT_VFALL -> A_IDLE and jumping
88 		 * right to B_IDLE...
89 		 */
90 		musb->xceiv->otg->default_a = 0;
91 		devctl &= ~MUSB_DEVCTL_SESSION;
92 		MUSB_DEV_MODE(musb);
93 	}
94 	musb_writeb(musb->mregs, MUSB_DEVCTL, devctl);
95 
96 	/*
97 	 * Devctl values will be updated after vbus goes below
98 	 * session_valid. The time taken depends on the capacitance
99 	 * on VBUS line. The max discharge time can be upto 1 sec
100 	 * as per the spec. Typically on our platform, it is 200ms
101 	 */
102 	if (!is_on)
103 		mdelay(200);
104 
105 	dev_dbg(musb->controller, "VBUS %s, devctl %02x\n",
106 		usb_otg_state_string(musb->xceiv->state),
107 		musb_readb(musb->mregs, MUSB_DEVCTL));
108 }
109 
110 static int musb_otg_notifications(struct notifier_block *nb,
111 		unsigned long event, void *unused)
112 {
113 	struct musb *musb = container_of(nb, struct musb, nb);
114 
115 	dev_dbg(musb->controller, "musb_otg_notifications %ld %s\n",
116 			event, usb_otg_state_string(musb->xceiv->state));
117 
118 	switch (event) {
119 	case UX500_MUSB_ID:
120 		dev_dbg(musb->controller, "ID GND\n");
121 		ux500_musb_set_vbus(musb, 1);
122 		break;
123 	case UX500_MUSB_VBUS:
124 		dev_dbg(musb->controller, "VBUS Connect\n");
125 		break;
126 	case UX500_MUSB_NONE:
127 		dev_dbg(musb->controller, "VBUS Disconnect\n");
128 		if (is_host_active(musb))
129 			ux500_musb_set_vbus(musb, 0);
130 		else
131 			musb->xceiv->state = OTG_STATE_B_IDLE;
132 		break;
133 	default:
134 		dev_dbg(musb->controller, "ID float\n");
135 		return NOTIFY_DONE;
136 	}
137 	return NOTIFY_OK;
138 }
139 
140 static irqreturn_t ux500_musb_interrupt(int irq, void *__hci)
141 {
142 	unsigned long   flags;
143 	irqreturn_t     retval = IRQ_NONE;
144 	struct musb     *musb = __hci;
145 
146 	spin_lock_irqsave(&musb->lock, flags);
147 
148 	musb->int_usb = musb_readb(musb->mregs, MUSB_INTRUSB);
149 	musb->int_tx = musb_readw(musb->mregs, MUSB_INTRTX);
150 	musb->int_rx = musb_readw(musb->mregs, MUSB_INTRRX);
151 
152 	if (musb->int_usb || musb->int_tx || musb->int_rx)
153 		retval = musb_interrupt(musb);
154 
155 	spin_unlock_irqrestore(&musb->lock, flags);
156 
157 	return retval;
158 }
159 
160 static int ux500_musb_init(struct musb *musb)
161 {
162 	int status;
163 
164 	musb->xceiv = usb_get_phy(USB_PHY_TYPE_USB2);
165 	if (IS_ERR_OR_NULL(musb->xceiv)) {
166 		pr_err("HS USB OTG: no transceiver configured\n");
167 		return -EPROBE_DEFER;
168 	}
169 
170 	musb->nb.notifier_call = musb_otg_notifications;
171 	status = usb_register_notifier(musb->xceiv, &musb->nb);
172 	if (status < 0) {
173 		dev_dbg(musb->controller, "notification register failed\n");
174 		return status;
175 	}
176 
177 	musb->isr = ux500_musb_interrupt;
178 
179 	return 0;
180 }
181 
182 static int ux500_musb_exit(struct musb *musb)
183 {
184 	usb_unregister_notifier(musb->xceiv, &musb->nb);
185 
186 	usb_put_phy(musb->xceiv);
187 
188 	return 0;
189 }
190 
191 static const struct musb_platform_ops ux500_ops = {
192 	.init		= ux500_musb_init,
193 	.exit		= ux500_musb_exit,
194 
195 	.set_vbus	= ux500_musb_set_vbus,
196 };
197 
198 static struct musb_hdrc_platform_data *
199 ux500_of_probe(struct platform_device *pdev, struct device_node *np)
200 {
201 	struct musb_hdrc_platform_data *pdata;
202 	const char *mode;
203 	int strlen;
204 
205 	pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
206 	if (!pdata)
207 		return NULL;
208 
209 	mode = of_get_property(np, "dr_mode", &strlen);
210 	if (!mode) {
211 		dev_err(&pdev->dev, "No 'dr_mode' property found\n");
212 		return NULL;
213 	}
214 
215 	if (strlen > 0) {
216 		if (!strcmp(mode, "host"))
217 			pdata->mode = MUSB_HOST;
218 		if (!strcmp(mode, "otg"))
219 			pdata->mode = MUSB_OTG;
220 		if (!strcmp(mode, "peripheral"))
221 			pdata->mode = MUSB_PERIPHERAL;
222 	}
223 
224 	return pdata;
225 }
226 
227 static int ux500_probe(struct platform_device *pdev)
228 {
229 	struct resource musb_resources[2];
230 	struct musb_hdrc_platform_data	*pdata = pdev->dev.platform_data;
231 	struct device_node		*np = pdev->dev.of_node;
232 	struct platform_device		*musb;
233 	struct ux500_glue		*glue;
234 	struct clk			*clk;
235 	int				ret = -ENOMEM;
236 
237 	if (!pdata) {
238 		if (np) {
239 			pdata = ux500_of_probe(pdev, np);
240 			if (!pdata)
241 				goto err0;
242 
243 			pdev->dev.platform_data = pdata;
244 		} else {
245 			dev_err(&pdev->dev, "no pdata or device tree found\n");
246 			goto err0;
247 		}
248 	}
249 
250 	glue = kzalloc(sizeof(*glue), GFP_KERNEL);
251 	if (!glue) {
252 		dev_err(&pdev->dev, "failed to allocate glue context\n");
253 		goto err0;
254 	}
255 
256 	musb = platform_device_alloc("musb-hdrc", PLATFORM_DEVID_AUTO);
257 	if (!musb) {
258 		dev_err(&pdev->dev, "failed to allocate musb device\n");
259 		goto err1;
260 	}
261 
262 	clk = clk_get(&pdev->dev, "usb");
263 	if (IS_ERR(clk)) {
264 		dev_err(&pdev->dev, "failed to get clock\n");
265 		ret = PTR_ERR(clk);
266 		goto err3;
267 	}
268 
269 	ret = clk_prepare_enable(clk);
270 	if (ret) {
271 		dev_err(&pdev->dev, "failed to enable clock\n");
272 		goto err4;
273 	}
274 
275 	musb->dev.parent		= &pdev->dev;
276 	musb->dev.dma_mask		= &pdev->dev.coherent_dma_mask;
277 	musb->dev.coherent_dma_mask	= pdev->dev.coherent_dma_mask;
278 	musb->dev.of_node		= pdev->dev.of_node;
279 
280 	glue->dev			= &pdev->dev;
281 	glue->musb			= musb;
282 	glue->clk			= clk;
283 
284 	pdata->platform_ops		= &ux500_ops;
285 	pdata->config 			= &ux500_musb_hdrc_config;
286 
287 	platform_set_drvdata(pdev, glue);
288 
289 	memset(musb_resources, 0x00, sizeof(*musb_resources) *
290 			ARRAY_SIZE(musb_resources));
291 
292 	musb_resources[0].name = pdev->resource[0].name;
293 	musb_resources[0].start = pdev->resource[0].start;
294 	musb_resources[0].end = pdev->resource[0].end;
295 	musb_resources[0].flags = pdev->resource[0].flags;
296 
297 	musb_resources[1].name = pdev->resource[1].name;
298 	musb_resources[1].start = pdev->resource[1].start;
299 	musb_resources[1].end = pdev->resource[1].end;
300 	musb_resources[1].flags = pdev->resource[1].flags;
301 
302 	ret = platform_device_add_resources(musb, musb_resources,
303 			ARRAY_SIZE(musb_resources));
304 	if (ret) {
305 		dev_err(&pdev->dev, "failed to add resources\n");
306 		goto err5;
307 	}
308 
309 	ret = platform_device_add_data(musb, pdata, sizeof(*pdata));
310 	if (ret) {
311 		dev_err(&pdev->dev, "failed to add platform_data\n");
312 		goto err5;
313 	}
314 
315 	ret = platform_device_add(musb);
316 	if (ret) {
317 		dev_err(&pdev->dev, "failed to register musb device\n");
318 		goto err5;
319 	}
320 
321 	return 0;
322 
323 err5:
324 	clk_disable_unprepare(clk);
325 
326 err4:
327 	clk_put(clk);
328 
329 err3:
330 	platform_device_put(musb);
331 
332 err1:
333 	kfree(glue);
334 
335 err0:
336 	return ret;
337 }
338 
339 static int ux500_remove(struct platform_device *pdev)
340 {
341 	struct ux500_glue	*glue = platform_get_drvdata(pdev);
342 
343 	platform_device_unregister(glue->musb);
344 	clk_disable_unprepare(glue->clk);
345 	clk_put(glue->clk);
346 	kfree(glue);
347 
348 	return 0;
349 }
350 
351 #ifdef CONFIG_PM
352 static int ux500_suspend(struct device *dev)
353 {
354 	struct ux500_glue	*glue = dev_get_drvdata(dev);
355 	struct musb		*musb = glue_to_musb(glue);
356 
357 	usb_phy_set_suspend(musb->xceiv, 1);
358 	clk_disable_unprepare(glue->clk);
359 
360 	return 0;
361 }
362 
363 static int ux500_resume(struct device *dev)
364 {
365 	struct ux500_glue	*glue = dev_get_drvdata(dev);
366 	struct musb		*musb = glue_to_musb(glue);
367 	int			ret;
368 
369 	ret = clk_prepare_enable(glue->clk);
370 	if (ret) {
371 		dev_err(dev, "failed to enable clock\n");
372 		return ret;
373 	}
374 
375 	usb_phy_set_suspend(musb->xceiv, 0);
376 
377 	return 0;
378 }
379 
380 static const struct dev_pm_ops ux500_pm_ops = {
381 	.suspend	= ux500_suspend,
382 	.resume		= ux500_resume,
383 };
384 
385 #define DEV_PM_OPS	(&ux500_pm_ops)
386 #else
387 #define DEV_PM_OPS	NULL
388 #endif
389 
390 static const struct of_device_id ux500_match[] = {
391         { .compatible = "stericsson,db8500-musb", },
392         {}
393 };
394 
395 static struct platform_driver ux500_driver = {
396 	.probe		= ux500_probe,
397 	.remove		= ux500_remove,
398 	.driver		= {
399 		.name	= "musb-ux500",
400 		.pm	= DEV_PM_OPS,
401 		.of_match_table = ux500_match,
402 	},
403 };
404 
405 MODULE_DESCRIPTION("UX500 MUSB Glue Layer");
406 MODULE_AUTHOR("Mian Yousaf Kaukab <mian.yousaf.kaukab@stericsson.com>");
407 MODULE_LICENSE("GPL v2");
408 module_platform_driver(ux500_driver);
409