tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1/*
2 * Driver for EHCI UHP on Atmel chips
3 *
4 * Copyright (C) 2009 Atmel Corporation,
5 * Nicolas Ferre <nicolas.ferre@atmel.com>
6 *
7 * Based on various ehci-*.c drivers
8 *
9 * This file is subject to the terms and conditions of the GNU General Public
10 * License. See the file COPYING in the main directory of this archive for
11 * more details.
12 */
13
14#include <linux/clk.h>
15#include <linux/dma-mapping.h>
16#include <linux/io.h>
17#include <linux/kernel.h>
18#include <linux/module.h>
19#include <linux/of.h>
20#include <linux/of_platform.h>
21#include <linux/platform_device.h>
22#include <linux/usb.h>
23#include <linux/usb/hcd.h>
24
25#include "ehci.h"
26
27#define DRIVER_DESC "EHCI Atmel driver"
28
29static const char hcd_name[] = "ehci-atmel";
30
31/* interface and function clocks */
32#define hcd_to_atmel_ehci_priv(h) \
33 ((struct atmel_ehci_priv *)hcd_to_ehci(h)->priv)
34
35struct atmel_ehci_priv {
36 struct clk *iclk;
37 struct clk *uclk;
38 bool clocked;
39};
40
41static struct hc_driver __read_mostly ehci_atmel_hc_driver;
42
43static const struct ehci_driver_overrides ehci_atmel_drv_overrides __initconst = {
44 .extra_priv_size = sizeof(struct atmel_ehci_priv),
45};
46
47/*-------------------------------------------------------------------------*/
48
49static void atmel_start_clock(struct atmel_ehci_priv *atmel_ehci)
50{
51 if (atmel_ehci->clocked)
52 return;
53
54 clk_prepare_enable(atmel_ehci->uclk);
55 clk_prepare_enable(atmel_ehci->iclk);
56 atmel_ehci->clocked = true;
57}
58
59static void atmel_stop_clock(struct atmel_ehci_priv *atmel_ehci)
60{
61 if (!atmel_ehci->clocked)
62 return;
63
64 clk_disable_unprepare(atmel_ehci->iclk);
65 clk_disable_unprepare(atmel_ehci->uclk);
66 atmel_ehci->clocked = false;
67}
68
69static void atmel_start_ehci(struct platform_device *pdev)
70{
71 struct usb_hcd *hcd = platform_get_drvdata(pdev);
72 struct atmel_ehci_priv *atmel_ehci = hcd_to_atmel_ehci_priv(hcd);
73
74 dev_dbg(&pdev->dev, "start\n");
75 atmel_start_clock(atmel_ehci);
76}
77
78static void atmel_stop_ehci(struct platform_device *pdev)
79{
80 struct usb_hcd *hcd = platform_get_drvdata(pdev);
81 struct atmel_ehci_priv *atmel_ehci = hcd_to_atmel_ehci_priv(hcd);
82
83 dev_dbg(&pdev->dev, "stop\n");
84 atmel_stop_clock(atmel_ehci);
85}
86
87/*-------------------------------------------------------------------------*/
88
89static int ehci_atmel_drv_probe(struct platform_device *pdev)
90{
91 struct usb_hcd *hcd;
92 const struct hc_driver *driver = &ehci_atmel_hc_driver;
93 struct resource *res;
94 struct ehci_hcd *ehci;
95 struct atmel_ehci_priv *atmel_ehci;
96 int irq;
97 int retval;
98
99 if (usb_disabled())
100 return -ENODEV;
101
102 pr_debug("Initializing Atmel-SoC USB Host Controller\n");
103
104 irq = platform_get_irq(pdev, 0);
105 if (irq <= 0) {
106 dev_err(&pdev->dev,
107 "Found HC with no IRQ. Check %s setup!\n",
108 dev_name(&pdev->dev));
109 retval = -ENODEV;
110 goto fail_create_hcd;
111 }
112
113 /* Right now device-tree probed devices don't get dma_mask set.
114 * Since shared usb code relies on it, set it here for now.
115 * Once we have dma capability bindings this can go away.
116 */
117 retval = dma_coerce_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));
118 if (retval)
119 goto fail_create_hcd;
120
121 hcd = usb_create_hcd(driver, &pdev->dev, dev_name(&pdev->dev));
122 if (!hcd) {
123 retval = -ENOMEM;
124 goto fail_create_hcd;
125 }
126 atmel_ehci = hcd_to_atmel_ehci_priv(hcd);
127
128 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
129 hcd->regs = devm_ioremap_resource(&pdev->dev, res);
130 if (IS_ERR(hcd->regs)) {
131 retval = PTR_ERR(hcd->regs);
132 goto fail_request_resource;
133 }
134
135 hcd->rsrc_start = res->start;
136 hcd->rsrc_len = resource_size(res);
137
138 atmel_ehci->iclk = devm_clk_get(&pdev->dev, "ehci_clk");
139 if (IS_ERR(atmel_ehci->iclk)) {
140 dev_err(&pdev->dev, "Error getting interface clock\n");
141 retval = -ENOENT;
142 goto fail_request_resource;
143 }
144
145 atmel_ehci->uclk = devm_clk_get(&pdev->dev, "usb_clk");
146 if (IS_ERR(atmel_ehci->uclk)) {
147 dev_err(&pdev->dev, "failed to get uclk\n");
148 retval = PTR_ERR(atmel_ehci->uclk);
149 goto fail_request_resource;
150 }
151
152 ehci = hcd_to_ehci(hcd);
153 /* registers start at offset 0x0 */
154 ehci->caps = hcd->regs;
155
156 atmel_start_ehci(pdev);
157
158 retval = usb_add_hcd(hcd, irq, IRQF_SHARED);
159 if (retval)
160 goto fail_add_hcd;
161 device_wakeup_enable(hcd->self.controller);
162
163 return retval;
164
165fail_add_hcd:
166 atmel_stop_ehci(pdev);
167fail_request_resource:
168 usb_put_hcd(hcd);
169fail_create_hcd:
170 dev_err(&pdev->dev, "init %s fail, %d\n",
171 dev_name(&pdev->dev), retval);
172
173 return retval;
174}
175
176static int ehci_atmel_drv_remove(struct platform_device *pdev)
177{
178 struct usb_hcd *hcd = platform_get_drvdata(pdev);
179
180 usb_remove_hcd(hcd);
181 usb_put_hcd(hcd);
182
183 atmel_stop_ehci(pdev);
184
185 return 0;
186}
187
188static int __maybe_unused ehci_atmel_drv_suspend(struct device *dev)
189{
190 struct usb_hcd *hcd = dev_get_drvdata(dev);
191 struct atmel_ehci_priv *atmel_ehci = hcd_to_atmel_ehci_priv(hcd);
192 int ret;
193
194 ret = ehci_suspend(hcd, false);
195 if (ret)
196 return ret;
197
198 atmel_stop_clock(atmel_ehci);
199 return 0;
200}
201
202static int __maybe_unused ehci_atmel_drv_resume(struct device *dev)
203{
204 struct usb_hcd *hcd = dev_get_drvdata(dev);
205 struct atmel_ehci_priv *atmel_ehci = hcd_to_atmel_ehci_priv(hcd);
206
207 atmel_start_clock(atmel_ehci);
208 return ehci_resume(hcd, false);
209}
210
211#ifdef CONFIG_OF
212static const struct of_device_id atmel_ehci_dt_ids[] = {
213 { .compatible = "atmel,at91sam9g45-ehci" },
214 { /* sentinel */ }
215};
216
217MODULE_DEVICE_TABLE(of, atmel_ehci_dt_ids);
218#endif
219
220static SIMPLE_DEV_PM_OPS(ehci_atmel_pm_ops, ehci_atmel_drv_suspend,
221 ehci_atmel_drv_resume);
222
223static struct platform_driver ehci_atmel_driver = {
224 .probe = ehci_atmel_drv_probe,
225 .remove = ehci_atmel_drv_remove,
226 .shutdown = usb_hcd_platform_shutdown,
227 .driver = {
228 .name = "atmel-ehci",
229 .pm = &ehci_atmel_pm_ops,
230 .of_match_table = of_match_ptr(atmel_ehci_dt_ids),
231 },
232};
233
234static int __init ehci_atmel_init(void)
235{
236 if (usb_disabled())
237 return -ENODEV;
238
239 pr_info("%s: " DRIVER_DESC "\n", hcd_name);
240 ehci_init_driver(&ehci_atmel_hc_driver, &ehci_atmel_drv_overrides);
241 return platform_driver_register(&ehci_atmel_driver);
242}
243module_init(ehci_atmel_init);
244
245static void __exit ehci_atmel_cleanup(void)
246{
247 platform_driver_unregister(&ehci_atmel_driver);
248}
249module_exit(ehci_atmel_cleanup);
250
251MODULE_DESCRIPTION(DRIVER_DESC);
252MODULE_ALIAS("platform:atmel-ehci");
253MODULE_AUTHOR("Nicolas Ferre");
254MODULE_LICENSE("GPL");