xref: /openbmc/linux/drivers/usb/musb/ux500.c (revision 9a29f5fc)
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->state = OTG_STATE_A_WAIT_VRISE;
66 			devctl |= MUSB_DEVCTL_SESSION;
67 			MUSB_HST_MODE(musb);
68 		}
69 	} else {
70 		musb->is_active = 0;
71 
72 		/* NOTE: we're skipping A_WAIT_VFALL -> A_IDLE and jumping
73 		 * right to B_IDLE...
74 		 */
75 		devctl &= ~MUSB_DEVCTL_SESSION;
76 		MUSB_DEV_MODE(musb);
77 	}
78 	musb_writeb(musb->mregs, MUSB_DEVCTL, devctl);
79 
80 	/*
81 	 * Devctl values will be updated after vbus goes below
82 	 * session_valid. The time taken depends on the capacitance
83 	 * on VBUS line. The max discharge time can be upto 1 sec
84 	 * as per the spec. Typically on our platform, it is 200ms
85 	 */
86 	if (!is_on)
87 		mdelay(200);
88 
89 	dev_dbg(musb->controller, "VBUS %s, devctl %02x\n",
90 		usb_otg_state_string(musb->xceiv->otg->state),
91 		musb_readb(musb->mregs, MUSB_DEVCTL));
92 }
93 
94 static int musb_otg_notifications(struct notifier_block *nb,
95 		unsigned long event, void *unused)
96 {
97 	struct musb *musb = container_of(nb, struct musb, nb);
98 
99 	dev_dbg(musb->controller, "musb_otg_notifications %ld %s\n",
100 			event, usb_otg_state_string(musb->xceiv->otg->state));
101 
102 	switch (event) {
103 	case UX500_MUSB_ID:
104 		dev_dbg(musb->controller, "ID GND\n");
105 		ux500_musb_set_vbus(musb, 1);
106 		break;
107 	case UX500_MUSB_VBUS:
108 		dev_dbg(musb->controller, "VBUS Connect\n");
109 		break;
110 	case UX500_MUSB_NONE:
111 		dev_dbg(musb->controller, "VBUS Disconnect\n");
112 		if (is_host_active(musb))
113 			ux500_musb_set_vbus(musb, 0);
114 		else
115 			musb->xceiv->otg->state = OTG_STATE_B_IDLE;
116 		break;
117 	default:
118 		dev_dbg(musb->controller, "ID float\n");
119 		return NOTIFY_DONE;
120 	}
121 	return NOTIFY_OK;
122 }
123 
124 static irqreturn_t ux500_musb_interrupt(int irq, void *__hci)
125 {
126 	unsigned long   flags;
127 	irqreturn_t     retval = IRQ_NONE;
128 	struct musb     *musb = __hci;
129 
130 	spin_lock_irqsave(&musb->lock, flags);
131 
132 	musb->int_usb = musb_readb(musb->mregs, MUSB_INTRUSB);
133 	musb->int_tx = musb_readw(musb->mregs, MUSB_INTRTX);
134 	musb->int_rx = musb_readw(musb->mregs, MUSB_INTRRX);
135 
136 	if (musb->int_usb || musb->int_tx || musb->int_rx)
137 		retval = musb_interrupt(musb);
138 
139 	spin_unlock_irqrestore(&musb->lock, flags);
140 
141 	return retval;
142 }
143 
144 static int ux500_musb_init(struct musb *musb)
145 {
146 	int status;
147 
148 	musb->xceiv = usb_get_phy(USB_PHY_TYPE_USB2);
149 	if (IS_ERR_OR_NULL(musb->xceiv)) {
150 		pr_err("HS USB OTG: no transceiver configured\n");
151 		return -EPROBE_DEFER;
152 	}
153 
154 	musb->nb.notifier_call = musb_otg_notifications;
155 	status = usb_register_notifier(musb->xceiv, &musb->nb);
156 	if (status < 0) {
157 		dev_dbg(musb->controller, "notification register failed\n");
158 		return status;
159 	}
160 
161 	musb->isr = ux500_musb_interrupt;
162 
163 	return 0;
164 }
165 
166 static int ux500_musb_exit(struct musb *musb)
167 {
168 	usb_unregister_notifier(musb->xceiv, &musb->nb);
169 
170 	usb_put_phy(musb->xceiv);
171 
172 	return 0;
173 }
174 
175 static const struct musb_platform_ops ux500_ops = {
176 	.quirks		= MUSB_DMA_UX500 | MUSB_INDEXED_EP,
177 #ifdef CONFIG_USB_UX500_DMA
178 	.dma_init	= ux500_dma_controller_create,
179 	.dma_exit	= ux500_dma_controller_destroy,
180 #endif
181 	.init		= ux500_musb_init,
182 	.exit		= ux500_musb_exit,
183 	.fifo_mode	= 5,
184 
185 	.set_vbus	= ux500_musb_set_vbus,
186 };
187 
188 static struct musb_hdrc_platform_data *
189 ux500_of_probe(struct platform_device *pdev, struct device_node *np)
190 {
191 	struct musb_hdrc_platform_data *pdata;
192 	const char *mode;
193 	int strlen;
194 
195 	pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
196 	if (!pdata)
197 		return NULL;
198 
199 	mode = of_get_property(np, "dr_mode", &strlen);
200 	if (!mode) {
201 		dev_err(&pdev->dev, "No 'dr_mode' property found\n");
202 		return NULL;
203 	}
204 
205 	if (strlen > 0) {
206 		if (!strcmp(mode, "host"))
207 			pdata->mode = MUSB_HOST;
208 		if (!strcmp(mode, "otg"))
209 			pdata->mode = MUSB_OTG;
210 		if (!strcmp(mode, "peripheral"))
211 			pdata->mode = MUSB_PERIPHERAL;
212 	}
213 
214 	return pdata;
215 }
216 
217 static int ux500_probe(struct platform_device *pdev)
218 {
219 	struct musb_hdrc_platform_data	*pdata = dev_get_platdata(&pdev->dev);
220 	struct device_node		*np = pdev->dev.of_node;
221 	struct platform_device		*musb;
222 	struct ux500_glue		*glue;
223 	struct clk			*clk;
224 	int				ret = -ENOMEM;
225 
226 	if (!pdata) {
227 		if (np) {
228 			pdata = ux500_of_probe(pdev, np);
229 			if (!pdata)
230 				goto err0;
231 
232 			pdev->dev.platform_data = pdata;
233 		} else {
234 			dev_err(&pdev->dev, "no pdata or device tree found\n");
235 			goto err0;
236 		}
237 	}
238 
239 	glue = devm_kzalloc(&pdev->dev, sizeof(*glue), GFP_KERNEL);
240 	if (!glue)
241 		goto err0;
242 
243 	musb = platform_device_alloc("musb-hdrc", PLATFORM_DEVID_AUTO);
244 	if (!musb) {
245 		dev_err(&pdev->dev, "failed to allocate musb device\n");
246 		goto err0;
247 	}
248 
249 	clk = devm_clk_get(&pdev->dev, NULL);
250 	if (IS_ERR(clk)) {
251 		dev_err(&pdev->dev, "failed to get clock\n");
252 		ret = PTR_ERR(clk);
253 		goto err1;
254 	}
255 
256 	ret = clk_prepare_enable(clk);
257 	if (ret) {
258 		dev_err(&pdev->dev, "failed to enable clock\n");
259 		goto err1;
260 	}
261 
262 	musb->dev.parent		= &pdev->dev;
263 	musb->dev.dma_mask		= &pdev->dev.coherent_dma_mask;
264 	musb->dev.coherent_dma_mask	= pdev->dev.coherent_dma_mask;
265 	device_set_of_node_from_dev(&musb->dev, &pdev->dev);
266 
267 	glue->dev			= &pdev->dev;
268 	glue->musb			= musb;
269 	glue->clk			= clk;
270 
271 	pdata->platform_ops		= &ux500_ops;
272 	pdata->config 			= &ux500_musb_hdrc_config;
273 
274 	platform_set_drvdata(pdev, glue);
275 
276 	ret = platform_device_add_resources(musb, pdev->resource, pdev->num_resources);
277 	if (ret) {
278 		dev_err(&pdev->dev, "failed to add resources\n");
279 		goto err2;
280 	}
281 
282 	ret = platform_device_add_data(musb, pdata, sizeof(*pdata));
283 	if (ret) {
284 		dev_err(&pdev->dev, "failed to add platform_data\n");
285 		goto err2;
286 	}
287 
288 	ret = platform_device_add(musb);
289 	if (ret) {
290 		dev_err(&pdev->dev, "failed to register musb device\n");
291 		goto err2;
292 	}
293 
294 	return 0;
295 
296 err2:
297 	clk_disable_unprepare(clk);
298 
299 err1:
300 	platform_device_put(musb);
301 
302 err0:
303 	return ret;
304 }
305 
306 static int ux500_remove(struct platform_device *pdev)
307 {
308 	struct ux500_glue	*glue = platform_get_drvdata(pdev);
309 
310 	platform_device_unregister(glue->musb);
311 	clk_disable_unprepare(glue->clk);
312 
313 	return 0;
314 }
315 
316 #ifdef CONFIG_PM_SLEEP
317 static int ux500_suspend(struct device *dev)
318 {
319 	struct ux500_glue	*glue = dev_get_drvdata(dev);
320 	struct musb		*musb = glue_to_musb(glue);
321 
322 	if (musb)
323 		usb_phy_set_suspend(musb->xceiv, 1);
324 
325 	clk_disable_unprepare(glue->clk);
326 
327 	return 0;
328 }
329 
330 static int ux500_resume(struct device *dev)
331 {
332 	struct ux500_glue	*glue = dev_get_drvdata(dev);
333 	struct musb		*musb = glue_to_musb(glue);
334 	int			ret;
335 
336 	ret = clk_prepare_enable(glue->clk);
337 	if (ret) {
338 		dev_err(dev, "failed to enable clock\n");
339 		return ret;
340 	}
341 
342 	if (musb)
343 		usb_phy_set_suspend(musb->xceiv, 0);
344 
345 	return 0;
346 }
347 #endif
348 
349 static SIMPLE_DEV_PM_OPS(ux500_pm_ops, ux500_suspend, ux500_resume);
350 
351 static const struct of_device_id ux500_match[] = {
352         { .compatible = "stericsson,db8500-musb", },
353         {}
354 };
355 
356 MODULE_DEVICE_TABLE(of, ux500_match);
357 
358 static struct platform_driver ux500_driver = {
359 	.probe		= ux500_probe,
360 	.remove		= ux500_remove,
361 	.driver		= {
362 		.name	= "musb-ux500",
363 		.pm	= &ux500_pm_ops,
364 		.of_match_table = ux500_match,
365 	},
366 };
367 
368 MODULE_DESCRIPTION("UX500 MUSB Glue Layer");
369 MODULE_AUTHOR("Mian Yousaf Kaukab <mian.yousaf.kaukab@stericsson.com>");
370 MODULE_LICENSE("GPL v2");
371 module_platform_driver(ux500_driver);
372