xref: /openbmc/linux/drivers/usb/host/ohci-at91.c (revision 22246614)
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 <asm/mach-types.h>
19 #include <asm/hardware.h>
20 #include <asm/gpio.h>
21 
22 #include <asm/arch/board.h>
23 #include <asm/arch/cpu.h>
24 
25 #ifndef CONFIG_ARCH_AT91
26 #error "CONFIG_ARCH_AT91 must be defined."
27 #endif
28 
29 /* interface and function clocks; sometimes also an AHB clock */
30 static struct clk *iclk, *fclk, *hclk;
31 static int clocked;
32 
33 extern int usb_disabled(void);
34 
35 /*-------------------------------------------------------------------------*/
36 
37 static void at91_start_clock(void)
38 {
39 	if (cpu_is_at91sam9261())
40 		clk_enable(hclk);
41 	clk_enable(iclk);
42 	clk_enable(fclk);
43 	clocked = 1;
44 }
45 
46 static void at91_stop_clock(void)
47 {
48 	clk_disable(fclk);
49 	clk_disable(iclk);
50 	if (cpu_is_at91sam9261())
51 		clk_disable(hclk);
52 	clocked = 0;
53 }
54 
55 static void at91_start_hc(struct platform_device *pdev)
56 {
57 	struct usb_hcd *hcd = platform_get_drvdata(pdev);
58 	struct ohci_regs __iomem *regs = hcd->regs;
59 
60 	dev_dbg(&pdev->dev, "start\n");
61 
62 	/*
63 	 * Start the USB clocks.
64 	 */
65 	at91_start_clock();
66 
67 	/*
68 	 * The USB host controller must remain in reset.
69 	 */
70 	writel(0, &regs->control);
71 }
72 
73 static void at91_stop_hc(struct platform_device *pdev)
74 {
75 	struct usb_hcd *hcd = platform_get_drvdata(pdev);
76 	struct ohci_regs __iomem *regs = hcd->regs;
77 
78 	dev_dbg(&pdev->dev, "stop\n");
79 
80 	/*
81 	 * Put the USB host controller into reset.
82 	 */
83 	writel(0, &regs->control);
84 
85 	/*
86 	 * Stop the USB clocks.
87 	 */
88 	at91_stop_clock();
89 }
90 
91 
92 /*-------------------------------------------------------------------------*/
93 
94 static int usb_hcd_at91_remove (struct usb_hcd *, struct platform_device *);
95 
96 /* configure so an HC device and id are always provided */
97 /* always called with process context; sleeping is OK */
98 
99 
100 /**
101  * usb_hcd_at91_probe - initialize AT91-based HCDs
102  * Context: !in_interrupt()
103  *
104  * Allocates basic resources for this USB host controller, and
105  * then invokes the start() method for the HCD associated with it
106  * through the hotplug entry's driver_data.
107  */
108 static int usb_hcd_at91_probe(const struct hc_driver *driver,
109 			struct platform_device *pdev)
110 {
111 	int retval;
112 	struct usb_hcd *hcd = NULL;
113 
114 	if (pdev->num_resources != 2) {
115 		pr_debug("hcd probe: invalid num_resources");
116 		return -ENODEV;
117 	}
118 
119 	if ((pdev->resource[0].flags != IORESOURCE_MEM)
120 			|| (pdev->resource[1].flags != IORESOURCE_IRQ)) {
121 		pr_debug("hcd probe: invalid resource type\n");
122 		return -ENODEV;
123 	}
124 
125 	hcd = usb_create_hcd(driver, &pdev->dev, "at91");
126 	if (!hcd)
127 		return -ENOMEM;
128 	hcd->rsrc_start = pdev->resource[0].start;
129 	hcd->rsrc_len = pdev->resource[0].end - pdev->resource[0].start + 1;
130 
131 	if (!request_mem_region(hcd->rsrc_start, hcd->rsrc_len, hcd_name)) {
132 		pr_debug("request_mem_region failed\n");
133 		retval = -EBUSY;
134 		goto err1;
135 	}
136 
137 	hcd->regs = ioremap(hcd->rsrc_start, hcd->rsrc_len);
138 	if (!hcd->regs) {
139 		pr_debug("ioremap failed\n");
140 		retval = -EIO;
141 		goto err2;
142 	}
143 
144 	iclk = clk_get(&pdev->dev, "ohci_clk");
145 	fclk = clk_get(&pdev->dev, "uhpck");
146 	if (cpu_is_at91sam9261())
147 		hclk = clk_get(&pdev->dev, "hck0");
148 
149 	at91_start_hc(pdev);
150 	ohci_hcd_init(hcd_to_ohci(hcd));
151 
152 	retval = usb_add_hcd(hcd, pdev->resource[1].start, IRQF_DISABLED);
153 	if (retval == 0)
154 		return retval;
155 
156 	/* Error handling */
157 	at91_stop_hc(pdev);
158 
159 	if (cpu_is_at91sam9261())
160 		clk_put(hclk);
161 	clk_put(fclk);
162 	clk_put(iclk);
163 
164 	iounmap(hcd->regs);
165 
166  err2:
167 	release_mem_region(hcd->rsrc_start, hcd->rsrc_len);
168 
169  err1:
170 	usb_put_hcd(hcd);
171 	return retval;
172 }
173 
174 
175 /* may be called with controller, bus, and devices active */
176 
177 /**
178  * usb_hcd_at91_remove - shutdown processing for AT91-based HCDs
179  * @dev: USB Host Controller being removed
180  * Context: !in_interrupt()
181  *
182  * Reverses the effect of usb_hcd_at91_probe(), first invoking
183  * the HCD's stop() method.  It is always called from a thread
184  * context, "rmmod" or something similar.
185  *
186  */
187 static int usb_hcd_at91_remove(struct usb_hcd *hcd,
188 				struct platform_device *pdev)
189 {
190 	usb_remove_hcd(hcd);
191 	at91_stop_hc(pdev);
192 	iounmap(hcd->regs);
193 	release_mem_region(hcd->rsrc_start, hcd->rsrc_len);
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 	return 0;
203 }
204 
205 /*-------------------------------------------------------------------------*/
206 
207 static int __devinit
208 ohci_at91_start (struct usb_hcd *hcd)
209 {
210 	struct at91_usbh_data	*board = hcd->self.controller->platform_data;
211 	struct ohci_hcd		*ohci = hcd_to_ohci (hcd);
212 	int			ret;
213 
214 	if ((ret = ohci_init(ohci)) < 0)
215 		return ret;
216 
217 	ohci->num_ports = board->ports;
218 
219 	if ((ret = ohci_run(ohci)) < 0) {
220 		err("can't start %s", hcd->self.bus_name);
221 		ohci_stop(hcd);
222 		return ret;
223 	}
224 	return 0;
225 }
226 
227 /*-------------------------------------------------------------------------*/
228 
229 static const struct hc_driver ohci_at91_hc_driver = {
230 	.description =		hcd_name,
231 	.product_desc =		"AT91 OHCI",
232 	.hcd_priv_size =	sizeof(struct ohci_hcd),
233 
234 	/*
235 	 * generic hardware linkage
236 	 */
237 	.irq =			ohci_irq,
238 	.flags =		HCD_USB11 | HCD_MEMORY,
239 
240 	/*
241 	 * basic lifecycle operations
242 	 */
243 	.start =		ohci_at91_start,
244 	.stop =			ohci_stop,
245 	.shutdown =		ohci_shutdown,
246 
247 	/*
248 	 * managing i/o requests and associated device resources
249 	 */
250 	.urb_enqueue =		ohci_urb_enqueue,
251 	.urb_dequeue =		ohci_urb_dequeue,
252 	.endpoint_disable =	ohci_endpoint_disable,
253 
254 	/*
255 	 * scheduling support
256 	 */
257 	.get_frame_number =	ohci_get_frame,
258 
259 	/*
260 	 * root hub support
261 	 */
262 	.hub_status_data =	ohci_hub_status_data,
263 	.hub_control =		ohci_hub_control,
264 #ifdef CONFIG_PM
265 	.bus_suspend =		ohci_bus_suspend,
266 	.bus_resume =		ohci_bus_resume,
267 #endif
268 	.start_port_reset =	ohci_start_port_reset,
269 };
270 
271 /*-------------------------------------------------------------------------*/
272 
273 static int ohci_hcd_at91_drv_probe(struct platform_device *pdev)
274 {
275 	struct at91_usbh_data	*pdata = pdev->dev.platform_data;
276 	int			i;
277 
278 	if (pdata) {
279 		/* REVISIT make the driver support per-port power switching,
280 		 * and also overcurrent detection.  Here we assume the ports
281 		 * are always powered while this driver is active, and use
282 		 * active-low power switches.
283 		 */
284 		for (i = 0; i < pdata->ports; i++) {
285 			if (pdata->vbus_pin[i] <= 0)
286 				continue;
287 			gpio_request(pdata->vbus_pin[i], "ohci_vbus");
288 			gpio_direction_output(pdata->vbus_pin[i], 0);
289 		}
290 	}
291 
292 	device_init_wakeup(&pdev->dev, 1);
293 	return usb_hcd_at91_probe(&ohci_at91_hc_driver, pdev);
294 }
295 
296 static int ohci_hcd_at91_drv_remove(struct platform_device *pdev)
297 {
298 	struct at91_usbh_data	*pdata = pdev->dev.platform_data;
299 	int			i;
300 
301 	if (pdata) {
302 		for (i = 0; i < pdata->ports; i++) {
303 			if (pdata->vbus_pin[i] <= 0)
304 				continue;
305 			gpio_direction_output(pdata->vbus_pin[i], 1);
306 			gpio_free(pdata->vbus_pin[i]);
307 		}
308 	}
309 
310 	device_init_wakeup(&pdev->dev, 0);
311 	return usb_hcd_at91_remove(platform_get_drvdata(pdev), pdev);
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