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 #define EHCI_INSNREG(index) ((index) * 4 + 0x90)
29 #define EHCI_INSNREG08_HSIC_EN BIT(2)
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
35 struct atmel_ehci_priv {
36 struct clk *iclk;
37 struct clk *uclk;
38 bool clocked;
39 };
40
41 static struct hc_driver __read_mostly ehci_atmel_hc_driver;
42
43 static const struct ehci_driver_overrides ehci_atmel_drv_overrides __initconst = {
44 .extra_priv_size = sizeof(struct atmel_ehci_priv),
45 };
46
47 /*-------------------------------------------------------------------------*/
48
atmel_start_clock(struct atmel_ehci_priv * atmel_ehci)49 static 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
atmel_stop_clock(struct atmel_ehci_priv * atmel_ehci)59 static 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
atmel_start_ehci(struct platform_device * pdev)69 static 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
atmel_stop_ehci(struct platform_device * pdev)78 static 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
ehci_atmel_drv_probe(struct platform_device * pdev)89 static 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 retval = irq;
107 goto fail_create_hcd;
108 }
109
110 /* Right now device-tree probed devices don't get dma_mask set.
111 * Since shared usb code relies on it, set it here for now.
112 * Once we have dma capability bindings this can go away.
113 */
114 retval = dma_coerce_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));
115 if (retval)
116 goto fail_create_hcd;
117
118 hcd = usb_create_hcd(driver, &pdev->dev, dev_name(&pdev->dev));
119 if (!hcd) {
120 retval = -ENOMEM;
121 goto fail_create_hcd;
122 }
123 atmel_ehci = hcd_to_atmel_ehci_priv(hcd);
124
125 hcd->regs = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
126 if (IS_ERR(hcd->regs)) {
127 retval = PTR_ERR(hcd->regs);
128 goto fail_request_resource;
129 }
130
131 hcd->rsrc_start = res->start;
132 hcd->rsrc_len = resource_size(res);
133
134 atmel_ehci->iclk = devm_clk_get(&pdev->dev, "ehci_clk");
135 if (IS_ERR(atmel_ehci->iclk)) {
136 dev_err(&pdev->dev, "Error getting interface clock\n");
137 retval = -ENOENT;
138 goto fail_request_resource;
139 }
140
141 atmel_ehci->uclk = devm_clk_get(&pdev->dev, "usb_clk");
142 if (IS_ERR(atmel_ehci->uclk)) {
143 dev_err(&pdev->dev, "failed to get uclk\n");
144 retval = PTR_ERR(atmel_ehci->uclk);
145 goto fail_request_resource;
146 }
147
148 ehci = hcd_to_ehci(hcd);
149 /* registers start at offset 0x0 */
150 ehci->caps = hcd->regs;
151
152 atmel_start_ehci(pdev);
153
154 retval = usb_add_hcd(hcd, irq, IRQF_SHARED);
155 if (retval)
156 goto fail_add_hcd;
157 device_wakeup_enable(hcd->self.controller);
158
159 if (of_usb_get_phy_mode(pdev->dev.of_node) == USBPHY_INTERFACE_MODE_HSIC)
160 writel(EHCI_INSNREG08_HSIC_EN, hcd->regs + EHCI_INSNREG(8));
161
162 return retval;
163
164 fail_add_hcd:
165 atmel_stop_ehci(pdev);
166 fail_request_resource:
167 usb_put_hcd(hcd);
168 fail_create_hcd:
169 dev_err(&pdev->dev, "init %s fail, %d\n",
170 dev_name(&pdev->dev), retval);
171
172 return retval;
173 }
174
ehci_atmel_drv_remove(struct platform_device * pdev)175 static void ehci_atmel_drv_remove(struct platform_device *pdev)
176 {
177 struct usb_hcd *hcd = platform_get_drvdata(pdev);
178
179 usb_remove_hcd(hcd);
180 usb_put_hcd(hcd);
181
182 atmel_stop_ehci(pdev);
183 }
184
ehci_atmel_drv_suspend(struct device * dev)185 static int __maybe_unused ehci_atmel_drv_suspend(struct device *dev)
186 {
187 struct usb_hcd *hcd = dev_get_drvdata(dev);
188 struct atmel_ehci_priv *atmel_ehci = hcd_to_atmel_ehci_priv(hcd);
189 int ret;
190
191 ret = ehci_suspend(hcd, false);
192 if (ret)
193 return ret;
194
195 atmel_stop_clock(atmel_ehci);
196 return 0;
197 }
198
ehci_atmel_drv_resume(struct device * dev)199 static int __maybe_unused ehci_atmel_drv_resume(struct device *dev)
200 {
201 struct usb_hcd *hcd = dev_get_drvdata(dev);
202 struct atmel_ehci_priv *atmel_ehci = hcd_to_atmel_ehci_priv(hcd);
203
204 atmel_start_clock(atmel_ehci);
205 ehci_resume(hcd, false);
206 return 0;
207 }
208
209 #ifdef CONFIG_OF
210 static const struct of_device_id atmel_ehci_dt_ids[] = {
211 { .compatible = "atmel,at91sam9g45-ehci" },
212 { /* sentinel */ }
213 };
214
215 MODULE_DEVICE_TABLE(of, atmel_ehci_dt_ids);
216 #endif
217
218 static SIMPLE_DEV_PM_OPS(ehci_atmel_pm_ops, ehci_atmel_drv_suspend,
219 ehci_atmel_drv_resume);
220
221 static struct platform_driver ehci_atmel_driver = {
222 .probe = ehci_atmel_drv_probe,
223 .remove_new = ehci_atmel_drv_remove,
224 .shutdown = usb_hcd_platform_shutdown,
225 .driver = {
226 .name = "atmel-ehci",
227 .pm = &ehci_atmel_pm_ops,
228 .of_match_table = of_match_ptr(atmel_ehci_dt_ids),
229 },
230 };
231
ehci_atmel_init(void)232 static int __init ehci_atmel_init(void)
233 {
234 if (usb_disabled())
235 return -ENODEV;
236
237 ehci_init_driver(&ehci_atmel_hc_driver, &ehci_atmel_drv_overrides);
238 return platform_driver_register(&ehci_atmel_driver);
239 }
240 module_init(ehci_atmel_init);
241
ehci_atmel_cleanup(void)242 static void __exit ehci_atmel_cleanup(void)
243 {
244 platform_driver_unregister(&ehci_atmel_driver);
245 }
246 module_exit(ehci_atmel_cleanup);
247
248 MODULE_DESCRIPTION(DRIVER_DESC);
249 MODULE_ALIAS("platform:atmel-ehci");
250 MODULE_AUTHOR("Nicolas Ferre");
251 MODULE_LICENSE("GPL");
252