USB: serial: visor: fix crash on detecting device without write_urbs
[pandora-kernel.git] / drivers / usb / host / ehci-mxc.c
1 /*
2  * Copyright (c) 2008 Sascha Hauer <s.hauer@pengutronix.de>, Pengutronix
3  * Copyright (c) 2009 Daniel Mack <daniel@caiaq.de>
4  *
5  * This program is free software; you can redistribute it and/or modify it
6  * under the terms of the GNU General Public License as published by the
7  * Free Software Foundation; either version 2 of the License, or (at your
8  * option) any later version.
9  *
10  * This program is distributed in the hope that it will be useful, but
11  * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
12  * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
13  * for more details.
14  *
15  * You should have received a copy of the GNU General Public License
16  * along with this program; if not, write to the Free Software Foundation,
17  * Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
18  */
19
20 #include <linux/platform_device.h>
21 #include <linux/clk.h>
22 #include <linux/delay.h>
23 #include <linux/usb/otg.h>
24 #include <linux/usb/ulpi.h>
25 #include <linux/slab.h>
26
27 #include <mach/hardware.h>
28 #include <mach/mxc_ehci.h>
29
30 #include <asm/mach-types.h>
31
32 #define ULPI_VIEWPORT_OFFSET    0x170
33
34 struct ehci_mxc_priv {
35         struct clk *usbclk, *ahbclk, *phy1clk;
36         struct usb_hcd *hcd;
37 };
38
39 /* called during probe() after chip reset completes */
40 static int ehci_mxc_setup(struct usb_hcd *hcd)
41 {
42         struct ehci_hcd *ehci = hcd_to_ehci(hcd);
43         int retval;
44
45         dbg_hcs_params(ehci, "reset");
46         dbg_hcc_params(ehci, "reset");
47
48         /* cache this readonly data; minimize chip reads */
49         ehci->hcs_params = ehci_readl(ehci, &ehci->caps->hcs_params);
50
51         hcd->has_tt = 1;
52
53         retval = ehci_halt(ehci);
54         if (retval)
55                 return retval;
56
57         /* data structure init */
58         retval = ehci_init(hcd);
59         if (retval)
60                 return retval;
61
62         ehci->sbrn = 0x20;
63
64         ehci_reset(ehci);
65
66         ehci_port_power(ehci, 0);
67         return 0;
68 }
69
70 static const struct hc_driver ehci_mxc_hc_driver = {
71         .description = hcd_name,
72         .product_desc = "Freescale On-Chip EHCI Host Controller",
73         .hcd_priv_size = sizeof(struct ehci_hcd),
74
75         /*
76          * generic hardware linkage
77          */
78         .irq = ehci_irq,
79         .flags = HCD_USB2 | HCD_MEMORY,
80
81         /*
82          * basic lifecycle operations
83          */
84         .reset = ehci_mxc_setup,
85         .start = ehci_run,
86         .stop = ehci_stop,
87         .shutdown = ehci_shutdown,
88
89         /*
90          * managing i/o requests and associated device resources
91          */
92         .urb_enqueue = ehci_urb_enqueue,
93         .urb_dequeue = ehci_urb_dequeue,
94         .endpoint_disable = ehci_endpoint_disable,
95         .endpoint_reset = ehci_endpoint_reset,
96
97         /*
98          * scheduling support
99          */
100         .get_frame_number = ehci_get_frame,
101
102         /*
103          * root hub support
104          */
105         .hub_status_data = ehci_hub_status_data,
106         .hub_control = ehci_hub_control,
107         .bus_suspend = ehci_bus_suspend,
108         .bus_resume = ehci_bus_resume,
109         .relinquish_port = ehci_relinquish_port,
110         .port_handed_over = ehci_port_handed_over,
111
112         .clear_tt_buffer_complete = ehci_clear_tt_buffer_complete,
113 };
114
115 static int ehci_mxc_drv_probe(struct platform_device *pdev)
116 {
117         struct mxc_usbh_platform_data *pdata = pdev->dev.platform_data;
118         struct usb_hcd *hcd;
119         struct resource *res;
120         int irq, ret;
121         unsigned int flags;
122         struct ehci_mxc_priv *priv;
123         struct device *dev = &pdev->dev;
124         struct ehci_hcd *ehci;
125
126         dev_info(&pdev->dev, "initializing i.MX USB Controller\n");
127
128         if (!pdata) {
129                 dev_err(dev, "No platform data given, bailing out.\n");
130                 return -EINVAL;
131         }
132
133         irq = platform_get_irq(pdev, 0);
134
135         hcd = usb_create_hcd(&ehci_mxc_hc_driver, dev, dev_name(dev));
136         if (!hcd)
137                 return -ENOMEM;
138
139         priv = kzalloc(sizeof(*priv), GFP_KERNEL);
140         if (!priv) {
141                 ret = -ENOMEM;
142                 goto err_alloc;
143         }
144
145         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
146         if (!res) {
147                 dev_err(dev, "Found HC with no register addr. Check setup!\n");
148                 ret = -ENODEV;
149                 goto err_get_resource;
150         }
151
152         hcd->rsrc_start = res->start;
153         hcd->rsrc_len = resource_size(res);
154
155         if (!request_mem_region(hcd->rsrc_start, hcd->rsrc_len, hcd_name)) {
156                 dev_dbg(dev, "controller already in use\n");
157                 ret = -EBUSY;
158                 goto err_request_mem;
159         }
160
161         hcd->regs = ioremap(hcd->rsrc_start, hcd->rsrc_len);
162         if (!hcd->regs) {
163                 dev_err(dev, "error mapping memory\n");
164                 ret = -EFAULT;
165                 goto err_ioremap;
166         }
167
168         /* enable clocks */
169         priv->usbclk = clk_get(dev, "usb");
170         if (IS_ERR(priv->usbclk)) {
171                 ret = PTR_ERR(priv->usbclk);
172                 goto err_clk;
173         }
174         clk_enable(priv->usbclk);
175
176         if (!cpu_is_mx35() && !cpu_is_mx25()) {
177                 priv->ahbclk = clk_get(dev, "usb_ahb");
178                 if (IS_ERR(priv->ahbclk)) {
179                         ret = PTR_ERR(priv->ahbclk);
180                         goto err_clk_ahb;
181                 }
182                 clk_enable(priv->ahbclk);
183         }
184
185         /* "dr" device has its own clock on i.MX51 */
186         if (cpu_is_mx51() && (pdev->id == 0)) {
187                 priv->phy1clk = clk_get(dev, "usb_phy1");
188                 if (IS_ERR(priv->phy1clk)) {
189                         ret = PTR_ERR(priv->phy1clk);
190                         goto err_clk_phy;
191                 }
192                 clk_enable(priv->phy1clk);
193         }
194
195
196         /* call platform specific init function */
197         if (pdata->init) {
198                 ret = pdata->init(pdev);
199                 if (ret) {
200                         dev_err(dev, "platform init failed\n");
201                         goto err_init;
202                 }
203                 /* platforms need some time to settle changed IO settings */
204                 mdelay(10);
205         }
206
207         ehci = hcd_to_ehci(hcd);
208
209         /* EHCI registers start at offset 0x100 */
210         ehci->caps = hcd->regs + 0x100;
211         ehci->regs = hcd->regs + 0x100 +
212                 HC_LENGTH(ehci, ehci_readl(ehci, &ehci->caps->hc_capbase));
213
214         /* set up the PORTSCx register */
215         ehci_writel(ehci, pdata->portsc, &ehci->regs->port_status[0]);
216
217         /* is this really needed? */
218         msleep(10);
219
220         /* Initialize the transceiver */
221         if (pdata->otg) {
222                 pdata->otg->io_priv = hcd->regs + ULPI_VIEWPORT_OFFSET;
223                 ret = otg_init(pdata->otg);
224                 if (ret) {
225                         dev_err(dev, "unable to init transceiver, probably missing\n");
226                         ret = -ENODEV;
227                         goto err_add;
228                 }
229                 ret = otg_set_vbus(pdata->otg, 1);
230                 if (ret) {
231                         dev_err(dev, "unable to enable vbus on transceiver\n");
232                         goto err_add;
233                 }
234         }
235
236         priv->hcd = hcd;
237         platform_set_drvdata(pdev, priv);
238
239         ret = usb_add_hcd(hcd, irq, IRQF_SHARED);
240         if (ret)
241                 goto err_add;
242
243         if (pdata->otg) {
244                 /*
245                  * efikamx and efikasb have some hardware bug which is
246                  * preventing usb to work unless CHRGVBUS is set.
247                  * It's in violation of USB specs
248                  */
249                 if (machine_is_mx51_efikamx() || machine_is_mx51_efikasb()) {
250                         flags = otg_io_read(pdata->otg, ULPI_OTG_CTRL);
251                         flags |= ULPI_OTG_CTRL_CHRGVBUS;
252                         ret = otg_io_write(pdata->otg, flags, ULPI_OTG_CTRL);
253                         if (ret) {
254                                 dev_err(dev, "unable to set CHRVBUS\n");
255                                 goto err_add;
256                         }
257                 }
258         }
259
260         return 0;
261
262 err_add:
263         if (pdata && pdata->exit)
264                 pdata->exit(pdev);
265 err_init:
266         if (priv->phy1clk) {
267                 clk_disable(priv->phy1clk);
268                 clk_put(priv->phy1clk);
269         }
270 err_clk_phy:
271         if (priv->ahbclk) {
272                 clk_disable(priv->ahbclk);
273                 clk_put(priv->ahbclk);
274         }
275 err_clk_ahb:
276         clk_disable(priv->usbclk);
277         clk_put(priv->usbclk);
278 err_clk:
279         iounmap(hcd->regs);
280 err_ioremap:
281         release_mem_region(hcd->rsrc_start, hcd->rsrc_len);
282 err_request_mem:
283 err_get_resource:
284         kfree(priv);
285 err_alloc:
286         usb_put_hcd(hcd);
287         return ret;
288 }
289
290 static int __exit ehci_mxc_drv_remove(struct platform_device *pdev)
291 {
292         struct mxc_usbh_platform_data *pdata = pdev->dev.platform_data;
293         struct ehci_mxc_priv *priv = platform_get_drvdata(pdev);
294         struct usb_hcd *hcd = priv->hcd;
295
296         if (pdata && pdata->exit)
297                 pdata->exit(pdev);
298
299         if (pdata && pdata->otg)
300                 otg_shutdown(pdata->otg);
301
302         usb_remove_hcd(hcd);
303         iounmap(hcd->regs);
304         release_mem_region(hcd->rsrc_start, hcd->rsrc_len);
305         usb_put_hcd(hcd);
306         platform_set_drvdata(pdev, NULL);
307
308         clk_disable(priv->usbclk);
309         clk_put(priv->usbclk);
310         if (priv->ahbclk) {
311                 clk_disable(priv->ahbclk);
312                 clk_put(priv->ahbclk);
313         }
314         if (priv->phy1clk) {
315                 clk_disable(priv->phy1clk);
316                 clk_put(priv->phy1clk);
317         }
318
319         kfree(priv);
320
321         return 0;
322 }
323
324 static void ehci_mxc_drv_shutdown(struct platform_device *pdev)
325 {
326         struct ehci_mxc_priv *priv = platform_get_drvdata(pdev);
327         struct usb_hcd *hcd = priv->hcd;
328
329         if (hcd->driver->shutdown)
330                 hcd->driver->shutdown(hcd);
331 }
332
333 MODULE_ALIAS("platform:mxc-ehci");
334
335 static struct platform_driver ehci_mxc_driver = {
336         .probe = ehci_mxc_drv_probe,
337         .remove = __exit_p(ehci_mxc_drv_remove),
338         .shutdown = ehci_mxc_drv_shutdown,
339         .driver = {
340                    .name = "mxc-ehci",
341         },
342 };