xref: /openbmc/linux/drivers/usb/musb/ux500.c (revision 82e6fdd6)
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 
9 #include <linux/module.h>
10 #include <linux/kernel.h>
11 #include <linux/clk.h>
12 #include <linux/err.h>
13 #include <linux/io.h>
14 #include <linux/of.h>
15 #include <linux/platform_device.h>
16 #include <linux/usb/musb-ux500.h>
17 
18 #include "musb_core.h"
19 
20 static const struct musb_hdrc_config ux500_musb_hdrc_config = {
21 	.multipoint	= true,
22 	.dyn_fifo	= true,
23 	.num_eps	= 16,
24 	.ram_bits	= 16,
25 };
26 
27 struct ux500_glue {
28 	struct device		*dev;
29 	struct platform_device	*musb;
30 	struct clk		*clk;
31 };
32 #define glue_to_musb(g)	platform_get_drvdata(g->musb)
33 
34 static void ux500_musb_set_vbus(struct musb *musb, int is_on)
35 {
36 	u8            devctl;
37 	unsigned long timeout = jiffies + msecs_to_jiffies(1000);
38 	/* HDRC controls CPEN, but beware current surges during device
39 	 * connect.  They can trigger transient overcurrent conditions
40 	 * that must be ignored.
41 	 */
42 
43 	devctl = musb_readb(musb->mregs, MUSB_DEVCTL);
44 
45 	if (is_on) {
46 		if (musb->xceiv->otg->state == OTG_STATE_A_IDLE) {
47 			/* start the session */
48 			devctl |= MUSB_DEVCTL_SESSION;
49 			musb_writeb(musb->mregs, MUSB_DEVCTL, devctl);
50 			/*
51 			 * Wait for the musb to set as A device to enable the
52 			 * VBUS
53 			 */
54 			while (musb_readb(musb->mregs, MUSB_DEVCTL) & 0x80) {
55 
56 				if (time_after(jiffies, timeout)) {
57 					dev_err(musb->controller,
58 					"configured as A device timeout");
59 					break;
60 				}
61 			}
62 
63 		} else {
64 			musb->is_active = 1;
65 			musb->xceiv->otg->default_a = 1;
66 			musb->xceiv->otg->state = OTG_STATE_A_WAIT_VRISE;
67 			devctl |= MUSB_DEVCTL_SESSION;
68 			MUSB_HST_MODE(musb);
69 		}
70 	} else {
71 		musb->is_active = 0;
72 
73 		/* NOTE: we're skipping A_WAIT_VFALL -> A_IDLE and jumping
74 		 * right to B_IDLE...
75 		 */
76 		musb->xceiv->otg->default_a = 0;
77 		devctl &= ~MUSB_DEVCTL_SESSION;
78 		MUSB_DEV_MODE(musb);
79 	}
80 	musb_writeb(musb->mregs, MUSB_DEVCTL, devctl);
81 
82 	/*
83 	 * Devctl values will be updated after vbus goes below
84 	 * session_valid. The time taken depends on the capacitance
85 	 * on VBUS line. The max discharge time can be upto 1 sec
86 	 * as per the spec. Typically on our platform, it is 200ms
87 	 */
88 	if (!is_on)
89 		mdelay(200);
90 
91 	dev_dbg(musb->controller, "VBUS %s, devctl %02x\n",
92 		usb_otg_state_string(musb->xceiv->otg->state),
93 		musb_readb(musb->mregs, MUSB_DEVCTL));
94 }
95 
96 static int musb_otg_notifications(struct notifier_block *nb,
97 		unsigned long event, void *unused)
98 {
99 	struct musb *musb = container_of(nb, struct musb, nb);
100 
101 	dev_dbg(musb->controller, "musb_otg_notifications %ld %s\n",
102 			event, usb_otg_state_string(musb->xceiv->otg->state));
103 
104 	switch (event) {
105 	case UX500_MUSB_ID:
106 		dev_dbg(musb->controller, "ID GND\n");
107 		ux500_musb_set_vbus(musb, 1);
108 		break;
109 	case UX500_MUSB_VBUS:
110 		dev_dbg(musb->controller, "VBUS Connect\n");
111 		break;
112 	case UX500_MUSB_NONE:
113 		dev_dbg(musb->controller, "VBUS Disconnect\n");
114 		if (is_host_active(musb))
115 			ux500_musb_set_vbus(musb, 0);
116 		else
117 			musb->xceiv->otg->state = OTG_STATE_B_IDLE;
118 		break;
119 	default:
120 		dev_dbg(musb->controller, "ID float\n");
121 		return NOTIFY_DONE;
122 	}
123 	return NOTIFY_OK;
124 }
125 
126 static irqreturn_t ux500_musb_interrupt(int irq, void *__hci)
127 {
128 	unsigned long   flags;
129 	irqreturn_t     retval = IRQ_NONE;
130 	struct musb     *musb = __hci;
131 
132 	spin_lock_irqsave(&musb->lock, flags);
133 
134 	musb->int_usb = musb_readb(musb->mregs, MUSB_INTRUSB);
135 	musb->int_tx = musb_readw(musb->mregs, MUSB_INTRTX);
136 	musb->int_rx = musb_readw(musb->mregs, MUSB_INTRRX);
137 
138 	if (musb->int_usb || musb->int_tx || musb->int_rx)
139 		retval = musb_interrupt(musb);
140 
141 	spin_unlock_irqrestore(&musb->lock, flags);
142 
143 	return retval;
144 }
145 
146 static int ux500_musb_init(struct musb *musb)
147 {
148 	int status;
149 
150 	musb->xceiv = usb_get_phy(USB_PHY_TYPE_USB2);
151 	if (IS_ERR_OR_NULL(musb->xceiv)) {
152 		pr_err("HS USB OTG: no transceiver configured\n");
153 		return -EPROBE_DEFER;
154 	}
155 
156 	musb->nb.notifier_call = musb_otg_notifications;
157 	status = usb_register_notifier(musb->xceiv, &musb->nb);
158 	if (status < 0) {
159 		dev_dbg(musb->controller, "notification register failed\n");
160 		return status;
161 	}
162 
163 	musb->isr = ux500_musb_interrupt;
164 
165 	return 0;
166 }
167 
168 static int ux500_musb_exit(struct musb *musb)
169 {
170 	usb_unregister_notifier(musb->xceiv, &musb->nb);
171 
172 	usb_put_phy(musb->xceiv);
173 
174 	return 0;
175 }
176 
177 static const struct musb_platform_ops ux500_ops = {
178 	.quirks		= MUSB_DMA_UX500 | MUSB_INDEXED_EP,
179 #ifdef CONFIG_USB_UX500_DMA
180 	.dma_init	= ux500_dma_controller_create,
181 	.dma_exit	= ux500_dma_controller_destroy,
182 #endif
183 	.init		= ux500_musb_init,
184 	.exit		= ux500_musb_exit,
185 	.fifo_mode	= 5,
186 
187 	.set_vbus	= ux500_musb_set_vbus,
188 };
189 
190 static struct musb_hdrc_platform_data *
191 ux500_of_probe(struct platform_device *pdev, struct device_node *np)
192 {
193 	struct musb_hdrc_platform_data *pdata;
194 	const char *mode;
195 	int strlen;
196 
197 	pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
198 	if (!pdata)
199 		return NULL;
200 
201 	mode = of_get_property(np, "dr_mode", &strlen);
202 	if (!mode) {
203 		dev_err(&pdev->dev, "No 'dr_mode' property found\n");
204 		return NULL;
205 	}
206 
207 	if (strlen > 0) {
208 		if (!strcmp(mode, "host"))
209 			pdata->mode = MUSB_HOST;
210 		if (!strcmp(mode, "otg"))
211 			pdata->mode = MUSB_OTG;
212 		if (!strcmp(mode, "peripheral"))
213 			pdata->mode = MUSB_PERIPHERAL;
214 	}
215 
216 	return pdata;
217 }
218 
219 static int ux500_probe(struct platform_device *pdev)
220 {
221 	struct resource musb_resources[2];
222 	struct musb_hdrc_platform_data	*pdata = dev_get_platdata(&pdev->dev);
223 	struct device_node		*np = pdev->dev.of_node;
224 	struct platform_device		*musb;
225 	struct ux500_glue		*glue;
226 	struct clk			*clk;
227 	int				ret = -ENOMEM;
228 
229 	if (!pdata) {
230 		if (np) {
231 			pdata = ux500_of_probe(pdev, np);
232 			if (!pdata)
233 				goto err0;
234 
235 			pdev->dev.platform_data = pdata;
236 		} else {
237 			dev_err(&pdev->dev, "no pdata or device tree found\n");
238 			goto err0;
239 		}
240 	}
241 
242 	glue = devm_kzalloc(&pdev->dev, sizeof(*glue), GFP_KERNEL);
243 	if (!glue)
244 		goto err0;
245 
246 	musb = platform_device_alloc("musb-hdrc", PLATFORM_DEVID_AUTO);
247 	if (!musb) {
248 		dev_err(&pdev->dev, "failed to allocate musb device\n");
249 		goto err0;
250 	}
251 
252 	clk = devm_clk_get(&pdev->dev, NULL);
253 	if (IS_ERR(clk)) {
254 		dev_err(&pdev->dev, "failed to get clock\n");
255 		ret = PTR_ERR(clk);
256 		goto err1;
257 	}
258 
259 	ret = clk_prepare_enable(clk);
260 	if (ret) {
261 		dev_err(&pdev->dev, "failed to enable clock\n");
262 		goto err1;
263 	}
264 
265 	musb->dev.parent		= &pdev->dev;
266 	musb->dev.dma_mask		= &pdev->dev.coherent_dma_mask;
267 	musb->dev.coherent_dma_mask	= pdev->dev.coherent_dma_mask;
268 
269 	glue->dev			= &pdev->dev;
270 	glue->musb			= musb;
271 	glue->clk			= clk;
272 
273 	pdata->platform_ops		= &ux500_ops;
274 	pdata->config 			= &ux500_musb_hdrc_config;
275 
276 	platform_set_drvdata(pdev, glue);
277 
278 	memset(musb_resources, 0x00, sizeof(*musb_resources) *
279 			ARRAY_SIZE(musb_resources));
280 
281 	musb_resources[0].name = pdev->resource[0].name;
282 	musb_resources[0].start = pdev->resource[0].start;
283 	musb_resources[0].end = pdev->resource[0].end;
284 	musb_resources[0].flags = pdev->resource[0].flags;
285 
286 	musb_resources[1].name = pdev->resource[1].name;
287 	musb_resources[1].start = pdev->resource[1].start;
288 	musb_resources[1].end = pdev->resource[1].end;
289 	musb_resources[1].flags = pdev->resource[1].flags;
290 
291 	ret = platform_device_add_resources(musb, musb_resources,
292 			ARRAY_SIZE(musb_resources));
293 	if (ret) {
294 		dev_err(&pdev->dev, "failed to add resources\n");
295 		goto err2;
296 	}
297 
298 	ret = platform_device_add_data(musb, pdata, sizeof(*pdata));
299 	if (ret) {
300 		dev_err(&pdev->dev, "failed to add platform_data\n");
301 		goto err2;
302 	}
303 
304 	ret = platform_device_add(musb);
305 	if (ret) {
306 		dev_err(&pdev->dev, "failed to register musb device\n");
307 		goto err2;
308 	}
309 
310 	return 0;
311 
312 err2:
313 	clk_disable_unprepare(clk);
314 
315 err1:
316 	platform_device_put(musb);
317 
318 err0:
319 	return ret;
320 }
321 
322 static int ux500_remove(struct platform_device *pdev)
323 {
324 	struct ux500_glue	*glue = platform_get_drvdata(pdev);
325 
326 	platform_device_unregister(glue->musb);
327 	clk_disable_unprepare(glue->clk);
328 
329 	return 0;
330 }
331 
332 #ifdef CONFIG_PM_SLEEP
333 static int ux500_suspend(struct device *dev)
334 {
335 	struct ux500_glue	*glue = dev_get_drvdata(dev);
336 	struct musb		*musb = glue_to_musb(glue);
337 
338 	if (musb)
339 		usb_phy_set_suspend(musb->xceiv, 1);
340 
341 	clk_disable_unprepare(glue->clk);
342 
343 	return 0;
344 }
345 
346 static int ux500_resume(struct device *dev)
347 {
348 	struct ux500_glue	*glue = dev_get_drvdata(dev);
349 	struct musb		*musb = glue_to_musb(glue);
350 	int			ret;
351 
352 	ret = clk_prepare_enable(glue->clk);
353 	if (ret) {
354 		dev_err(dev, "failed to enable clock\n");
355 		return ret;
356 	}
357 
358 	if (musb)
359 		usb_phy_set_suspend(musb->xceiv, 0);
360 
361 	return 0;
362 }
363 #endif
364 
365 static SIMPLE_DEV_PM_OPS(ux500_pm_ops, ux500_suspend, ux500_resume);
366 
367 static const struct of_device_id ux500_match[] = {
368         { .compatible = "stericsson,db8500-musb", },
369         {}
370 };
371 
372 MODULE_DEVICE_TABLE(of, ux500_match);
373 
374 static struct platform_driver ux500_driver = {
375 	.probe		= ux500_probe,
376 	.remove		= ux500_remove,
377 	.driver		= {
378 		.name	= "musb-ux500",
379 		.pm	= &ux500_pm_ops,
380 		.of_match_table = ux500_match,
381 	},
382 };
383 
384 MODULE_DESCRIPTION("UX500 MUSB Glue Layer");
385 MODULE_AUTHOR("Mian Yousaf Kaukab <mian.yousaf.kaukab@stericsson.com>");
386 MODULE_LICENSE("GPL v2");
387 module_platform_driver(ux500_driver);
388