xref: /openbmc/linux/drivers/usb/host/ohci-at91.c (revision b627b4ed)
1 /*
2  * OHCI HCD (Host Controller Driver) for USB.
3  *
4  *  Copyright (C) 2004 SAN People (Pty) Ltd.
5  *  Copyright (C) 2005 Thibaut VARENE <varenet@parisc-linux.org>
6  *
7  * AT91 Bus Glue
8  *
9  * Based on fragments of 2.4 driver by Rick Bronson.
10  * Based on ohci-omap.c
11  *
12  * This file is licenced under the GPL.
13  */
14 
15 #include <linux/clk.h>
16 #include <linux/platform_device.h>
17 
18 #include <mach/hardware.h>
19 #include <asm/gpio.h>
20 
21 #include <mach/board.h>
22 #include <mach/cpu.h>
23 
24 #ifndef CONFIG_ARCH_AT91
25 #error "CONFIG_ARCH_AT91 must be defined."
26 #endif
27 
28 /* interface and function clocks; sometimes also an AHB clock */
29 static struct clk *iclk, *fclk, *hclk;
30 static int clocked;
31 
32 extern int usb_disabled(void);
33 
34 /*-------------------------------------------------------------------------*/
35 
36 static void at91_start_clock(void)
37 {
38 	if (cpu_is_at91sam9261())
39 		clk_enable(hclk);
40 	clk_enable(iclk);
41 	clk_enable(fclk);
42 	clocked = 1;
43 }
44 
45 static void at91_stop_clock(void)
46 {
47 	clk_disable(fclk);
48 	clk_disable(iclk);
49 	if (cpu_is_at91sam9261())
50 		clk_disable(hclk);
51 	clocked = 0;
52 }
53 
54 static void at91_start_hc(struct platform_device *pdev)
55 {
56 	struct usb_hcd *hcd = platform_get_drvdata(pdev);
57 	struct ohci_regs __iomem *regs = hcd->regs;
58 
59 	dev_dbg(&pdev->dev, "start\n");
60 
61 	/*
62 	 * Start the USB clocks.
63 	 */
64 	at91_start_clock();
65 
66 	/*
67 	 * The USB host controller must remain in reset.
68 	 */
69 	writel(0, &regs->control);
70 }
71 
72 static void at91_stop_hc(struct platform_device *pdev)
73 {
74 	struct usb_hcd *hcd = platform_get_drvdata(pdev);
75 	struct ohci_regs __iomem *regs = hcd->regs;
76 
77 	dev_dbg(&pdev->dev, "stop\n");
78 
79 	/*
80 	 * Put the USB host controller into reset.
81 	 */
82 	writel(0, &regs->control);
83 
84 	/*
85 	 * Stop the USB clocks.
86 	 */
87 	at91_stop_clock();
88 }
89 
90 
91 /*-------------------------------------------------------------------------*/
92 
93 static void usb_hcd_at91_remove (struct usb_hcd *, struct platform_device *);
94 
95 /* configure so an HC device and id are always provided */
96 /* always called with process context; sleeping is OK */
97 
98 
99 /**
100  * usb_hcd_at91_probe - initialize AT91-based HCDs
101  * Context: !in_interrupt()
102  *
103  * Allocates basic resources for this USB host controller, and
104  * then invokes the start() method for the HCD associated with it
105  * through the hotplug entry's driver_data.
106  */
107 static int usb_hcd_at91_probe(const struct hc_driver *driver,
108 			struct platform_device *pdev)
109 {
110 	int retval;
111 	struct usb_hcd *hcd = NULL;
112 
113 	if (pdev->num_resources != 2) {
114 		pr_debug("hcd probe: invalid num_resources");
115 		return -ENODEV;
116 	}
117 
118 	if ((pdev->resource[0].flags != IORESOURCE_MEM)
119 			|| (pdev->resource[1].flags != IORESOURCE_IRQ)) {
120 		pr_debug("hcd probe: invalid resource type\n");
121 		return -ENODEV;
122 	}
123 
124 	hcd = usb_create_hcd(driver, &pdev->dev, "at91");
125 	if (!hcd)
126 		return -ENOMEM;
127 	hcd->rsrc_start = pdev->resource[0].start;
128 	hcd->rsrc_len = pdev->resource[0].end - pdev->resource[0].start + 1;
129 
130 	if (!request_mem_region(hcd->rsrc_start, hcd->rsrc_len, hcd_name)) {
131 		pr_debug("request_mem_region failed\n");
132 		retval = -EBUSY;
133 		goto err1;
134 	}
135 
136 	hcd->regs = ioremap(hcd->rsrc_start, hcd->rsrc_len);
137 	if (!hcd->regs) {
138 		pr_debug("ioremap failed\n");
139 		retval = -EIO;
140 		goto err2;
141 	}
142 
143 	iclk = clk_get(&pdev->dev, "ohci_clk");
144 	fclk = clk_get(&pdev->dev, "uhpck");
145 	if (cpu_is_at91sam9261())
146 		hclk = clk_get(&pdev->dev, "hck0");
147 
148 	at91_start_hc(pdev);
149 	ohci_hcd_init(hcd_to_ohci(hcd));
150 
151 	retval = usb_add_hcd(hcd, pdev->resource[1].start, IRQF_DISABLED);
152 	if (retval == 0)
153 		return retval;
154 
155 	/* Error handling */
156 	at91_stop_hc(pdev);
157 
158 	if (cpu_is_at91sam9261())
159 		clk_put(hclk);
160 	clk_put(fclk);
161 	clk_put(iclk);
162 
163 	iounmap(hcd->regs);
164 
165  err2:
166 	release_mem_region(hcd->rsrc_start, hcd->rsrc_len);
167 
168  err1:
169 	usb_put_hcd(hcd);
170 	return retval;
171 }
172 
173 
174 /* may be called with controller, bus, and devices active */
175 
176 /**
177  * usb_hcd_at91_remove - shutdown processing for AT91-based HCDs
178  * @dev: USB Host Controller being removed
179  * Context: !in_interrupt()
180  *
181  * Reverses the effect of usb_hcd_at91_probe(), first invoking
182  * the HCD's stop() method.  It is always called from a thread
183  * context, "rmmod" or something similar.
184  *
185  */
186 static void usb_hcd_at91_remove(struct usb_hcd *hcd,
187 				struct platform_device *pdev)
188 {
189 	usb_remove_hcd(hcd);
190 	at91_stop_hc(pdev);
191 	iounmap(hcd->regs);
192 	release_mem_region(hcd->rsrc_start, hcd->rsrc_len);
193 	usb_put_hcd(hcd);
194 
195 	if (cpu_is_at91sam9261())
196 		clk_put(hclk);
197 	clk_put(fclk);
198 	clk_put(iclk);
199 	fclk = iclk = hclk = NULL;
200 
201 	dev_set_drvdata(&pdev->dev, NULL);
202 }
203 
204 /*-------------------------------------------------------------------------*/
205 
206 static int __devinit
207 ohci_at91_start (struct usb_hcd *hcd)
208 {
209 	struct at91_usbh_data	*board = hcd->self.controller->platform_data;
210 	struct ohci_hcd		*ohci = hcd_to_ohci (hcd);
211 	int			ret;
212 
213 	if ((ret = ohci_init(ohci)) < 0)
214 		return ret;
215 
216 	ohci->num_ports = board->ports;
217 
218 	if ((ret = ohci_run(ohci)) < 0) {
219 		err("can't start %s", hcd->self.bus_name);
220 		ohci_stop(hcd);
221 		return ret;
222 	}
223 	return 0;
224 }
225 
226 /*-------------------------------------------------------------------------*/
227 
228 static const struct hc_driver ohci_at91_hc_driver = {
229 	.description =		hcd_name,
230 	.product_desc =		"AT91 OHCI",
231 	.hcd_priv_size =	sizeof(struct ohci_hcd),
232 
233 	/*
234 	 * generic hardware linkage
235 	 */
236 	.irq =			ohci_irq,
237 	.flags =		HCD_USB11 | HCD_MEMORY,
238 
239 	/*
240 	 * basic lifecycle operations
241 	 */
242 	.start =		ohci_at91_start,
243 	.stop =			ohci_stop,
244 	.shutdown =		ohci_shutdown,
245 
246 	/*
247 	 * managing i/o requests and associated device resources
248 	 */
249 	.urb_enqueue =		ohci_urb_enqueue,
250 	.urb_dequeue =		ohci_urb_dequeue,
251 	.endpoint_disable =	ohci_endpoint_disable,
252 
253 	/*
254 	 * scheduling support
255 	 */
256 	.get_frame_number =	ohci_get_frame,
257 
258 	/*
259 	 * root hub support
260 	 */
261 	.hub_status_data =	ohci_hub_status_data,
262 	.hub_control =		ohci_hub_control,
263 #ifdef CONFIG_PM
264 	.bus_suspend =		ohci_bus_suspend,
265 	.bus_resume =		ohci_bus_resume,
266 #endif
267 	.start_port_reset =	ohci_start_port_reset,
268 };
269 
270 /*-------------------------------------------------------------------------*/
271 
272 static int ohci_hcd_at91_drv_probe(struct platform_device *pdev)
273 {
274 	struct at91_usbh_data	*pdata = pdev->dev.platform_data;
275 	int			i;
276 
277 	if (pdata) {
278 		/* REVISIT make the driver support per-port power switching,
279 		 * and also overcurrent detection.  Here we assume the ports
280 		 * are always powered while this driver is active, and use
281 		 * active-low power switches.
282 		 */
283 		for (i = 0; i < ARRAY_SIZE(pdata->vbus_pin); i++) {
284 			if (pdata->vbus_pin[i] <= 0)
285 				continue;
286 			gpio_request(pdata->vbus_pin[i], "ohci_vbus");
287 			gpio_direction_output(pdata->vbus_pin[i], 0);
288 		}
289 	}
290 
291 	device_init_wakeup(&pdev->dev, 1);
292 	return usb_hcd_at91_probe(&ohci_at91_hc_driver, pdev);
293 }
294 
295 static int ohci_hcd_at91_drv_remove(struct platform_device *pdev)
296 {
297 	struct at91_usbh_data	*pdata = pdev->dev.platform_data;
298 	int			i;
299 
300 	if (pdata) {
301 		for (i = 0; i < ARRAY_SIZE(pdata->vbus_pin); i++) {
302 			if (pdata->vbus_pin[i] <= 0)
303 				continue;
304 			gpio_direction_output(pdata->vbus_pin[i], 1);
305 			gpio_free(pdata->vbus_pin[i]);
306 		}
307 	}
308 
309 	device_init_wakeup(&pdev->dev, 0);
310 	usb_hcd_at91_remove(platform_get_drvdata(pdev), pdev);
311 	return 0;
312 }
313 
314 #ifdef CONFIG_PM
315 
316 static int
317 ohci_hcd_at91_drv_suspend(struct platform_device *pdev, pm_message_t mesg)
318 {
319 	struct usb_hcd	*hcd = platform_get_drvdata(pdev);
320 	struct ohci_hcd	*ohci = hcd_to_ohci(hcd);
321 
322 	if (device_may_wakeup(&pdev->dev))
323 		enable_irq_wake(hcd->irq);
324 
325 	/*
326 	 * The integrated transceivers seem unable to notice disconnect,
327 	 * reconnect, or wakeup without the 48 MHz clock active.  so for
328 	 * correctness, always discard connection state (using reset).
329 	 *
330 	 * REVISIT: some boards will be able to turn VBUS off...
331 	 */
332 	if (at91_suspend_entering_slow_clock()) {
333 		ohci_usb_reset (ohci);
334 		at91_stop_clock();
335 	}
336 
337 	return 0;
338 }
339 
340 static int ohci_hcd_at91_drv_resume(struct platform_device *pdev)
341 {
342 	struct usb_hcd	*hcd = platform_get_drvdata(pdev);
343 
344 	if (device_may_wakeup(&pdev->dev))
345 		disable_irq_wake(hcd->irq);
346 
347 	if (!clocked)
348 		at91_start_clock();
349 
350 	ohci_finish_controller_resume(hcd);
351 	return 0;
352 }
353 #else
354 #define ohci_hcd_at91_drv_suspend NULL
355 #define ohci_hcd_at91_drv_resume  NULL
356 #endif
357 
358 MODULE_ALIAS("platform:at91_ohci");
359 
360 static struct platform_driver ohci_hcd_at91_driver = {
361 	.probe		= ohci_hcd_at91_drv_probe,
362 	.remove		= ohci_hcd_at91_drv_remove,
363 	.shutdown	= usb_hcd_platform_shutdown,
364 	.suspend	= ohci_hcd_at91_drv_suspend,
365 	.resume		= ohci_hcd_at91_drv_resume,
366 	.driver		= {
367 		.name	= "at91_ohci",
368 		.owner	= THIS_MODULE,
369 	},
370 };
371