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;
36 /*-------------------------------------------------------------------------*/
38 static void atmel_start_clock(void)
40 clk_prepare_enable(iclk);
41 clk_prepare_enable(fclk);
45 static void atmel_stop_clock(void)
47 clk_disable_unprepare(fclk);
48 clk_disable_unprepare(iclk);
52 static void atmel_start_ehci(struct platform_device *pdev)
54 dev_dbg(&pdev->dev, "start\n");
58 static void atmel_stop_ehci(struct platform_device *pdev)
60 dev_dbg(&pdev->dev, "stop\n");
64 /*-------------------------------------------------------------------------*/
66 static int ehci_atmel_drv_probe(struct platform_device *pdev)
69 const struct hc_driver *driver = &ehci_atmel_hc_driver;
71 struct ehci_hcd *ehci;
78 pr_debug("Initializing Atmel-SoC USB Host Controller\n");
80 irq = platform_get_irq(pdev, 0);
83 "Found HC with no IRQ. Check %s setup!\n",
84 dev_name(&pdev->dev));
89 /* Right now device-tree probed devices don't get dma_mask set.
90 * Since shared usb code relies on it, set it here for now.
91 * Once we have dma capability bindings this can go away.
93 retval = dma_coerce_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));
97 hcd = usb_create_hcd(driver, &pdev->dev, dev_name(&pdev->dev));
100 goto fail_create_hcd;
103 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
106 "Found HC with no register addr. Check %s setup!\n",
107 dev_name(&pdev->dev));
109 goto fail_request_resource;
111 hcd->rsrc_start = res->start;
112 hcd->rsrc_len = resource_size(res);
114 hcd->regs = devm_ioremap_resource(&pdev->dev, res);
115 if (IS_ERR(hcd->regs)) {
116 retval = PTR_ERR(hcd->regs);
117 goto fail_request_resource;
120 iclk = devm_clk_get(&pdev->dev, "ehci_clk");
122 dev_err(&pdev->dev, "Error getting interface clock\n");
124 goto fail_request_resource;
126 fclk = devm_clk_get(&pdev->dev, "uhpck");
128 dev_err(&pdev->dev, "Error getting function clock\n");
130 goto fail_request_resource;
133 ehci = hcd_to_ehci(hcd);
134 /* registers start at offset 0x0 */
135 ehci->caps = hcd->regs;
137 atmel_start_ehci(pdev);
139 retval = usb_add_hcd(hcd, irq, IRQF_SHARED);
146 atmel_stop_ehci(pdev);
147 fail_request_resource:
150 dev_err(&pdev->dev, "init %s fail, %d\n",
151 dev_name(&pdev->dev), retval);
156 static int ehci_atmel_drv_remove(struct platform_device *pdev)
158 struct usb_hcd *hcd = platform_get_drvdata(pdev);
163 atmel_stop_ehci(pdev);
170 static const struct of_device_id atmel_ehci_dt_ids[] = {
171 { .compatible = "atmel,at91sam9g45-ehci" },
175 MODULE_DEVICE_TABLE(of, atmel_ehci_dt_ids);
178 static struct platform_driver ehci_atmel_driver = {
179 .probe = ehci_atmel_drv_probe,
180 .remove = ehci_atmel_drv_remove,
181 .shutdown = usb_hcd_platform_shutdown,
183 .name = "atmel-ehci",
184 .of_match_table = of_match_ptr(atmel_ehci_dt_ids),
188 static int __init ehci_atmel_init(void)
193 pr_info("%s: " DRIVER_DESC "\n", hcd_name);
194 ehci_init_driver(&ehci_atmel_hc_driver, NULL);
195 return platform_driver_register(&ehci_atmel_driver);
197 module_init(ehci_atmel_init);
199 static void __exit ehci_atmel_cleanup(void)
201 platform_driver_unregister(&ehci_atmel_driver);
203 module_exit(ehci_atmel_cleanup);
205 MODULE_DESCRIPTION(DRIVER_DESC);
206 MODULE_ALIAS("platform:atmel-ehci");
207 MODULE_AUTHOR("Nicolas Ferre");
208 MODULE_LICENSE("GPL");