1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Driver for EHCI UHP on Atmel chips
4 *
5 * Copyright (C) 2009 Atmel Corporation,
6 * Nicolas Ferre <nicolas.ferre@atmel.com>
7 *
8 * Based on various ehci-*.c drivers
9 */
10
11 #include <linux/clk.h>
12 #include <linux/dma-mapping.h>
13 #include <linux/io.h>
14 #include <linux/kernel.h>
15 #include <linux/module.h>
16 #include <linux/of.h>
17 #include <linux/of_platform.h>
18 #include <linux/platform_device.h>
19 #include <linux/usb.h>
20 #include <linux/usb/hcd.h>
21 #include <linux/usb/phy.h>
22 #include <linux/usb/of.h>
23
24 #include "ehci.h"
25
26 #define DRIVER_DESC "EHCI Atmel driver"
27
28 static const char hcd_name[] = "ehci-atmel";
29
30 #define EHCI_INSNREG(index) ((index) * 4 + 0x90)
31 #define EHCI_INSNREG08_HSIC_EN BIT(2)
32
33 /* interface and function clocks */
34 #define hcd_to_atmel_ehci_priv(h) \
35 ((struct atmel_ehci_priv *)hcd_to_ehci(h)->priv)
36
37 struct atmel_ehci_priv {
38 struct clk *iclk;
39 struct clk *uclk;
40 bool clocked;
41 };
42
43 static struct hc_driver __read_mostly ehci_atmel_hc_driver;
44
45 static const struct ehci_driver_overrides ehci_atmel_drv_overrides __initconst = {
46 .extra_priv_size = sizeof(struct atmel_ehci_priv),
47 };
48
49 /*-------------------------------------------------------------------------*/
50
atmel_start_clock(struct atmel_ehci_priv * atmel_ehci)51 static void atmel_start_clock(struct atmel_ehci_priv *atmel_ehci)
52 {
53 if (atmel_ehci->clocked)
54 return;
55
56 clk_prepare_enable(atmel_ehci->uclk);
57 clk_prepare_enable(atmel_ehci->iclk);
58 atmel_ehci->clocked = true;
59 }
60
atmel_stop_clock(struct atmel_ehci_priv * atmel_ehci)61 static void atmel_stop_clock(struct atmel_ehci_priv *atmel_ehci)
62 {
63 if (!atmel_ehci->clocked)
64 return;
65
66 clk_disable_unprepare(atmel_ehci->iclk);
67 clk_disable_unprepare(atmel_ehci->uclk);
68 atmel_ehci->clocked = false;
69 }
70
atmel_start_ehci(struct platform_device * pdev)71 static void atmel_start_ehci(struct platform_device *pdev)
72 {
73 struct usb_hcd *hcd = platform_get_drvdata(pdev);
74 struct atmel_ehci_priv *atmel_ehci = hcd_to_atmel_ehci_priv(hcd);
75
76 dev_dbg(&pdev->dev, "start\n");
77 atmel_start_clock(atmel_ehci);
78 }
79
atmel_stop_ehci(struct platform_device * pdev)80 static void atmel_stop_ehci(struct platform_device *pdev)
81 {
82 struct usb_hcd *hcd = platform_get_drvdata(pdev);
83 struct atmel_ehci_priv *atmel_ehci = hcd_to_atmel_ehci_priv(hcd);
84
85 dev_dbg(&pdev->dev, "stop\n");
86 atmel_stop_clock(atmel_ehci);
87 }
88
89 /*-------------------------------------------------------------------------*/
90
ehci_atmel_drv_probe(struct platform_device * pdev)91 static int ehci_atmel_drv_probe(struct platform_device *pdev)
92 {
93 struct usb_hcd *hcd;
94 const struct hc_driver *driver = &ehci_atmel_hc_driver;
95 struct resource *res;
96 struct ehci_hcd *ehci;
97 struct atmel_ehci_priv *atmel_ehci;
98 int irq;
99 int retval;
100
101 if (usb_disabled())
102 return -ENODEV;
103
104 pr_debug("Initializing Atmel-SoC USB Host Controller\n");
105
106 irq = platform_get_irq(pdev, 0);
107 if (irq <= 0) {
108 retval = -ENODEV;
109 goto fail_create_hcd;
110 }
111
112 /* Right now device-tree probed devices don't get dma_mask set.
113 * Since shared usb code relies on it, set it here for now.
114 * Once we have dma capability bindings this can go away.
115 */
116 retval = dma_coerce_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));
117 if (retval)
118 goto fail_create_hcd;
119
120 hcd = usb_create_hcd(driver, &pdev->dev, dev_name(&pdev->dev));
121 if (!hcd) {
122 retval = -ENOMEM;
123 goto fail_create_hcd;
124 }
125 atmel_ehci = hcd_to_atmel_ehci_priv(hcd);
126
127 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
128 hcd->regs = devm_ioremap_resource(&pdev->dev, res);
129 if (IS_ERR(hcd->regs)) {
130 retval = PTR_ERR(hcd->regs);
131 goto fail_request_resource;
132 }
133
134 hcd->rsrc_start = res->start;
135 hcd->rsrc_len = resource_size(res);
136
137 atmel_ehci->iclk = devm_clk_get(&pdev->dev, "ehci_clk");
138 if (IS_ERR(atmel_ehci->iclk)) {
139 dev_err(&pdev->dev, "Error getting interface clock\n");
140 retval = -ENOENT;
141 goto fail_request_resource;
142 }
143
144 atmel_ehci->uclk = devm_clk_get(&pdev->dev, "usb_clk");
145 if (IS_ERR(atmel_ehci->uclk)) {
146 dev_err(&pdev->dev, "failed to get uclk\n");
147 retval = PTR_ERR(atmel_ehci->uclk);
148 goto fail_request_resource;
149 }
150
151 ehci = hcd_to_ehci(hcd);
152 /* registers start at offset 0x0 */
153 ehci->caps = hcd->regs;
154
155 atmel_start_ehci(pdev);
156
157 retval = usb_add_hcd(hcd, irq, IRQF_SHARED);
158 if (retval)
159 goto fail_add_hcd;
160 device_wakeup_enable(hcd->self.controller);
161
162 if (of_usb_get_phy_mode(pdev->dev.of_node) == USBPHY_INTERFACE_MODE_HSIC)
163 writel(EHCI_INSNREG08_HSIC_EN, hcd->regs + EHCI_INSNREG(8));
164
165 return retval;
166
167 fail_add_hcd:
168 atmel_stop_ehci(pdev);
169 fail_request_resource:
170 usb_put_hcd(hcd);
171 fail_create_hcd:
172 dev_err(&pdev->dev, "init %s fail, %d\n",
173 dev_name(&pdev->dev), retval);
174
175 return retval;
176 }
177
ehci_atmel_drv_remove(struct platform_device * pdev)178 static int ehci_atmel_drv_remove(struct platform_device *pdev)
179 {
180 struct usb_hcd *hcd = platform_get_drvdata(pdev);
181
182 usb_remove_hcd(hcd);
183 usb_put_hcd(hcd);
184
185 atmel_stop_ehci(pdev);
186
187 return 0;
188 }
189
ehci_atmel_drv_suspend(struct device * dev)190 static int __maybe_unused ehci_atmel_drv_suspend(struct device *dev)
191 {
192 struct usb_hcd *hcd = dev_get_drvdata(dev);
193 struct atmel_ehci_priv *atmel_ehci = hcd_to_atmel_ehci_priv(hcd);
194 int ret;
195
196 ret = ehci_suspend(hcd, false);
197 if (ret)
198 return ret;
199
200 atmel_stop_clock(atmel_ehci);
201 return 0;
202 }
203
ehci_atmel_drv_resume(struct device * dev)204 static int __maybe_unused ehci_atmel_drv_resume(struct device *dev)
205 {
206 struct usb_hcd *hcd = dev_get_drvdata(dev);
207 struct atmel_ehci_priv *atmel_ehci = hcd_to_atmel_ehci_priv(hcd);
208
209 atmel_start_clock(atmel_ehci);
210 ehci_resume(hcd, false);
211 return 0;
212 }
213
214 #ifdef CONFIG_OF
215 static const struct of_device_id atmel_ehci_dt_ids[] = {
216 { .compatible = "atmel,at91sam9g45-ehci" },
217 { /* sentinel */ }
218 };
219
220 MODULE_DEVICE_TABLE(of, atmel_ehci_dt_ids);
221 #endif
222
223 static SIMPLE_DEV_PM_OPS(ehci_atmel_pm_ops, ehci_atmel_drv_suspend,
224 ehci_atmel_drv_resume);
225
226 static struct platform_driver ehci_atmel_driver = {
227 .probe = ehci_atmel_drv_probe,
228 .remove = ehci_atmel_drv_remove,
229 .shutdown = usb_hcd_platform_shutdown,
230 .driver = {
231 .name = "atmel-ehci",
232 .pm = &ehci_atmel_pm_ops,
233 .of_match_table = of_match_ptr(atmel_ehci_dt_ids),
234 },
235 };
236
ehci_atmel_init(void)237 static int __init ehci_atmel_init(void)
238 {
239 if (usb_disabled())
240 return -ENODEV;
241
242 pr_info("%s: " DRIVER_DESC "\n", hcd_name);
243 ehci_init_driver(&ehci_atmel_hc_driver, &ehci_atmel_drv_overrides);
244 return platform_driver_register(&ehci_atmel_driver);
245 }
246 module_init(ehci_atmel_init);
247
ehci_atmel_cleanup(void)248 static void __exit ehci_atmel_cleanup(void)
249 {
250 platform_driver_unregister(&ehci_atmel_driver);
251 }
252 module_exit(ehci_atmel_cleanup);
253
254 MODULE_DESCRIPTION(DRIVER_DESC);
255 MODULE_ALIAS("platform:atmel-ehci");
256 MODULE_AUTHOR("Nicolas Ferre");
257 MODULE_LICENSE("GPL");
258