2 * Driver for EHCI UHP on Atmel chips
4 * Copyright (C) 2009 Atmel Corporation,
5 * Nicolas Ferre <nicolas.ferre@atmel.com>
7 * Based on various ehci-*.c drivers
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
14 #include <linux/clk.h>
15 #include <linux/dma-mapping.h>
17 #include <linux/kernel.h>
18 #include <linux/module.h>
20 #include <linux/of_platform.h>
21 #include <linux/platform_device.h>
22 #include <linux/usb.h>
23 #include <linux/usb/hcd.h>
27 #define DRIVER_DESC "EHCI Atmel driver"
29 static const char hcd_name[] = "ehci-atmel";
30 static struct hc_driver __read_mostly ehci_atmel_hc_driver;
32 /* interface and function clocks */
33 static struct clk *iclk, *fclk, *uclk;
36 /*-------------------------------------------------------------------------*/
38 static void atmel_start_clock(void)
40 if (IS_ENABLED(CONFIG_COMMON_CLK)) {
41 clk_set_rate(uclk, 48000000);
42 clk_prepare_enable(uclk);
44 clk_prepare_enable(iclk);
45 clk_prepare_enable(fclk);
49 static void atmel_stop_clock(void)
51 clk_disable_unprepare(fclk);
52 clk_disable_unprepare(iclk);
53 if (IS_ENABLED(CONFIG_COMMON_CLK))
54 clk_disable_unprepare(uclk);
58 static void atmel_start_ehci(struct platform_device *pdev)
60 dev_dbg(&pdev->dev, "start\n");
64 static void atmel_stop_ehci(struct platform_device *pdev)
66 dev_dbg(&pdev->dev, "stop\n");
70 /*-------------------------------------------------------------------------*/
72 static int ehci_atmel_drv_probe(struct platform_device *pdev)
75 const struct hc_driver *driver = &ehci_atmel_hc_driver;
77 struct ehci_hcd *ehci;
84 pr_debug("Initializing Atmel-SoC USB Host Controller\n");
86 irq = platform_get_irq(pdev, 0);
89 "Found HC with no IRQ. Check %s setup!\n",
90 dev_name(&pdev->dev));
95 /* Right now device-tree probed devices don't get dma_mask set.
96 * Since shared usb code relies on it, set it here for now.
97 * Once we have dma capability bindings this can go away.
99 if (!pdev->dev.dma_mask)
100 pdev->dev.dma_mask = &pdev->dev.coherent_dma_mask;
101 if (!pdev->dev.coherent_dma_mask)
102 pdev->dev.coherent_dma_mask = DMA_BIT_MASK(32);
104 hcd = usb_create_hcd(driver, &pdev->dev, dev_name(&pdev->dev));
107 goto fail_create_hcd;
110 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
113 "Found HC with no register addr. Check %s setup!\n",
114 dev_name(&pdev->dev));
116 goto fail_request_resource;
118 hcd->rsrc_start = res->start;
119 hcd->rsrc_len = resource_size(res);
121 hcd->regs = devm_ioremap_resource(&pdev->dev, res);
122 if (IS_ERR(hcd->regs)) {
123 retval = PTR_ERR(hcd->regs);
124 goto fail_request_resource;
127 iclk = devm_clk_get(&pdev->dev, "ehci_clk");
129 dev_err(&pdev->dev, "Error getting interface clock\n");
131 goto fail_request_resource;
133 fclk = devm_clk_get(&pdev->dev, "uhpck");
135 dev_err(&pdev->dev, "Error getting function clock\n");
137 goto fail_request_resource;
139 if (IS_ENABLED(CONFIG_COMMON_CLK)) {
140 uclk = devm_clk_get(&pdev->dev, "usb_clk");
142 dev_err(&pdev->dev, "failed to get uclk\n");
143 retval = PTR_ERR(uclk);
144 goto fail_request_resource;
148 ehci = hcd_to_ehci(hcd);
149 /* registers start at offset 0x0 */
150 ehci->caps = hcd->regs;
152 atmel_start_ehci(pdev);
154 retval = usb_add_hcd(hcd, irq, IRQF_SHARED);
161 atmel_stop_ehci(pdev);
162 fail_request_resource:
165 dev_err(&pdev->dev, "init %s fail, %d\n",
166 dev_name(&pdev->dev), retval);
171 static int ehci_atmel_drv_remove(struct platform_device *pdev)
173 struct usb_hcd *hcd = platform_get_drvdata(pdev);
178 atmel_stop_ehci(pdev);
185 static const struct of_device_id atmel_ehci_dt_ids[] = {
186 { .compatible = "atmel,at91sam9g45-ehci" },
190 MODULE_DEVICE_TABLE(of, atmel_ehci_dt_ids);
193 static struct platform_driver ehci_atmel_driver = {
194 .probe = ehci_atmel_drv_probe,
195 .remove = ehci_atmel_drv_remove,
196 .shutdown = usb_hcd_platform_shutdown,
198 .name = "atmel-ehci",
199 .of_match_table = of_match_ptr(atmel_ehci_dt_ids),
203 static int __init ehci_atmel_init(void)
208 pr_info("%s: " DRIVER_DESC "\n", hcd_name);
209 ehci_init_driver(&ehci_atmel_hc_driver, NULL);
210 return platform_driver_register(&ehci_atmel_driver);
212 module_init(ehci_atmel_init);
214 static void __exit ehci_atmel_cleanup(void)
216 platform_driver_unregister(&ehci_atmel_driver);
218 module_exit(ehci_atmel_cleanup);
220 MODULE_DESCRIPTION(DRIVER_DESC);
221 MODULE_ALIAS("platform:atmel-ehci");
222 MODULE_AUTHOR("Nicolas Ferre");
223 MODULE_LICENSE("GPL");