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
20static 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
27struct 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
34static 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
94static 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
124static 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
144static 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
166static 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
175static 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
188static struct musb_hdrc_platform_data *
189ux500_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
217static 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
296err2:
297	clk_disable_unprepare(clk);
298
299err1:
300	platform_device_put(musb);
301
302err0:
303	return ret;
304}
305
306static void 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
314#ifdef CONFIG_PM_SLEEP
315static int ux500_suspend(struct device *dev)
316{
317	struct ux500_glue	*glue = dev_get_drvdata(dev);
318	struct musb		*musb = glue_to_musb(glue);
319
320	if (musb)
321		usb_phy_set_suspend(musb->xceiv, 1);
322
323	clk_disable_unprepare(glue->clk);
324
325	return 0;
326}
327
328static int ux500_resume(struct device *dev)
329{
330	struct ux500_glue	*glue = dev_get_drvdata(dev);
331	struct musb		*musb = glue_to_musb(glue);
332	int			ret;
333
334	ret = clk_prepare_enable(glue->clk);
335	if (ret) {
336		dev_err(dev, "failed to enable clock\n");
337		return ret;
338	}
339
340	if (musb)
341		usb_phy_set_suspend(musb->xceiv, 0);
342
343	return 0;
344}
345#endif
346
347static SIMPLE_DEV_PM_OPS(ux500_pm_ops, ux500_suspend, ux500_resume);
348
349static const struct of_device_id ux500_match[] = {
350        { .compatible = "stericsson,db8500-musb", },
351        {}
352};
353
354MODULE_DEVICE_TABLE(of, ux500_match);
355
356static struct platform_driver ux500_driver = {
357	.probe		= ux500_probe,
358	.remove_new	= ux500_remove,
359	.driver		= {
360		.name	= "musb-ux500",
361		.pm	= &ux500_pm_ops,
362		.of_match_table = ux500_match,
363	},
364};
365
366MODULE_DESCRIPTION("UX500 MUSB Glue Layer");
367MODULE_AUTHOR("Mian Yousaf Kaukab <mian.yousaf.kaukab@stericsson.com>");
368MODULE_LICENSE("GPL v2");
369module_platform_driver(ux500_driver);
370