xref: /openbmc/linux/drivers/usb/musb/ux500.c (revision 5fd54ace) 
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Copyright (C) 2010 ST-Ericsson AB
4  * Mian Yousaf Kaukab <mian.yousaf.kaukab@stericsson.com>
5  *
6  * Based on omap2430.c
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License as published by
10  * the Free Software Foundation; either version 2 of the License, or
11  * (at your option) any later version.
12  *
13  * This program is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16  * GNU General Public License for more details.
17  *
18  * You should have received a copy of the GNU General Public License
19  * along with this program; if not, write to the Free Software
20  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
21  */
22 
23 #include <linux/module.h>
24 #include <linux/kernel.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 const 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->otg->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->otg->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->otg->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->otg->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->otg->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 	.quirks		= MUSB_DMA_UX500 | MUSB_INDEXED_EP,
193 #ifdef CONFIG_USB_UX500_DMA
194 	.dma_init	= ux500_dma_controller_create,
195 	.dma_exit	= ux500_dma_controller_destroy,
196 #endif
197 	.init		= ux500_musb_init,
198 	.exit		= ux500_musb_exit,
199 	.fifo_mode	= 5,
200 
201 	.set_vbus	= ux500_musb_set_vbus,
202 };
203 
204 static struct musb_hdrc_platform_data *
205 ux500_of_probe(struct platform_device *pdev, struct device_node *np)
206 {
207 	struct musb_hdrc_platform_data *pdata;
208 	const char *mode;
209 	int strlen;
210 
211 	pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
212 	if (!pdata)
213 		return NULL;
214 
215 	mode = of_get_property(np, "dr_mode", &strlen);
216 	if (!mode) {
217 		dev_err(&pdev->dev, "No 'dr_mode' property found\n");
218 		return NULL;
219 	}
220 
221 	if (strlen > 0) {
222 		if (!strcmp(mode, "host"))
223 			pdata->mode = MUSB_HOST;
224 		if (!strcmp(mode, "otg"))
225 			pdata->mode = MUSB_OTG;
226 		if (!strcmp(mode, "peripheral"))
227 			pdata->mode = MUSB_PERIPHERAL;
228 	}
229 
230 	return pdata;
231 }
232 
233 static int ux500_probe(struct platform_device *pdev)
234 {
235 	struct resource musb_resources[2];
236 	struct musb_hdrc_platform_data	*pdata = dev_get_platdata(&pdev->dev);
237 	struct device_node		*np = pdev->dev.of_node;
238 	struct platform_device		*musb;
239 	struct ux500_glue		*glue;
240 	struct clk			*clk;
241 	int				ret = -ENOMEM;
242 
243 	if (!pdata) {
244 		if (np) {
245 			pdata = ux500_of_probe(pdev, np);
246 			if (!pdata)
247 				goto err0;
248 
249 			pdev->dev.platform_data = pdata;
250 		} else {
251 			dev_err(&pdev->dev, "no pdata or device tree found\n");
252 			goto err0;
253 		}
254 	}
255 
256 	glue = devm_kzalloc(&pdev->dev, sizeof(*glue), GFP_KERNEL);
257 	if (!glue)
258 		goto err0;
259 
260 	musb = platform_device_alloc("musb-hdrc", PLATFORM_DEVID_AUTO);
261 	if (!musb) {
262 		dev_err(&pdev->dev, "failed to allocate musb device\n");
263 		goto err0;
264 	}
265 
266 	clk = devm_clk_get(&pdev->dev, NULL);
267 	if (IS_ERR(clk)) {
268 		dev_err(&pdev->dev, "failed to get clock\n");
269 		ret = PTR_ERR(clk);
270 		goto err1;
271 	}
272 
273 	ret = clk_prepare_enable(clk);
274 	if (ret) {
275 		dev_err(&pdev->dev, "failed to enable clock\n");
276 		goto err1;
277 	}
278 
279 	musb->dev.parent		= &pdev->dev;
280 	musb->dev.dma_mask		= &pdev->dev.coherent_dma_mask;
281 	musb->dev.coherent_dma_mask	= pdev->dev.coherent_dma_mask;
282 
283 	glue->dev			= &pdev->dev;
284 	glue->musb			= musb;
285 	glue->clk			= clk;
286 
287 	pdata->platform_ops		= &ux500_ops;
288 	pdata->config 			= &ux500_musb_hdrc_config;
289 
290 	platform_set_drvdata(pdev, glue);
291 
292 	memset(musb_resources, 0x00, sizeof(*musb_resources) *
293 			ARRAY_SIZE(musb_resources));
294 
295 	musb_resources[0].name = pdev->resource[0].name;
296 	musb_resources[0].start = pdev->resource[0].start;
297 	musb_resources[0].end = pdev->resource[0].end;
298 	musb_resources[0].flags = pdev->resource[0].flags;
299 
300 	musb_resources[1].name = pdev->resource[1].name;
301 	musb_resources[1].start = pdev->resource[1].start;
302 	musb_resources[1].end = pdev->resource[1].end;
303 	musb_resources[1].flags = pdev->resource[1].flags;
304 
305 	ret = platform_device_add_resources(musb, musb_resources,
306 			ARRAY_SIZE(musb_resources));
307 	if (ret) {
308 		dev_err(&pdev->dev, "failed to add resources\n");
309 		goto err2;
310 	}
311 
312 	ret = platform_device_add_data(musb, pdata, sizeof(*pdata));
313 	if (ret) {
314 		dev_err(&pdev->dev, "failed to add platform_data\n");
315 		goto err2;
316 	}
317 
318 	ret = platform_device_add(musb);
319 	if (ret) {
320 		dev_err(&pdev->dev, "failed to register musb device\n");
321 		goto err2;
322 	}
323 
324 	return 0;
325 
326 err2:
327 	clk_disable_unprepare(clk);
328 
329 err1:
330 	platform_device_put(musb);
331 
332 err0:
333 	return ret;
334 }
335 
336 static int ux500_remove(struct platform_device *pdev)
337 {
338 	struct ux500_glue	*glue = platform_get_drvdata(pdev);
339 
340 	platform_device_unregister(glue->musb);
341 	clk_disable_unprepare(glue->clk);
342 
343 	return 0;
344 }
345 
346 #ifdef CONFIG_PM_SLEEP
347 static int ux500_suspend(struct device *dev)
348 {
349 	struct ux500_glue	*glue = dev_get_drvdata(dev);
350 	struct musb		*musb = glue_to_musb(glue);
351 
352 	if (musb)
353 		usb_phy_set_suspend(musb->xceiv, 1);
354 
355 	clk_disable_unprepare(glue->clk);
356 
357 	return 0;
358 }
359 
360 static int ux500_resume(struct device *dev)
361 {
362 	struct ux500_glue	*glue = dev_get_drvdata(dev);
363 	struct musb		*musb = glue_to_musb(glue);
364 	int			ret;
365 
366 	ret = clk_prepare_enable(glue->clk);
367 	if (ret) {
368 		dev_err(dev, "failed to enable clock\n");
369 		return ret;
370 	}
371 
372 	if (musb)
373 		usb_phy_set_suspend(musb->xceiv, 0);
374 
375 	return 0;
376 }
377 #endif
378 
379 static SIMPLE_DEV_PM_OPS(ux500_pm_ops, ux500_suspend, ux500_resume);
380 
381 static const struct of_device_id ux500_match[] = {
382         { .compatible = "stericsson,db8500-musb", },
383         {}
384 };
385 
386 MODULE_DEVICE_TABLE(of, ux500_match);
387 
388 static struct platform_driver ux500_driver = {
389 	.probe		= ux500_probe,
390 	.remove		= ux500_remove,
391 	.driver		= {
392 		.name	= "musb-ux500",
393 		.pm	= &ux500_pm_ops,
394 		.of_match_table = ux500_match,
395 	},
396 };
397 
398 MODULE_DESCRIPTION("UX500 MUSB Glue Layer");
399 MODULE_AUTHOR("Mian Yousaf Kaukab <mian.yousaf.kaukab@stericsson.com>");
400 MODULE_LICENSE("GPL v2");
401 module_platform_driver(ux500_driver);
402