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 29 static 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 35 struct atmel_ehci_priv { 36 struct clk *iclk; 37 struct clk *fclk; 38 struct clk *uclk; 39 bool clocked; 40 }; 41 42 static struct hc_driver __read_mostly ehci_atmel_hc_driver; 43 44 static const struct ehci_driver_overrides ehci_atmel_drv_overrides __initconst = { 45 .extra_priv_size = sizeof(struct atmel_ehci_priv), 46 }; 47 48 /*-------------------------------------------------------------------------*/ 49 50 static void atmel_start_clock(struct atmel_ehci_priv *atmel_ehci) 51 { 52 if (atmel_ehci->clocked) 53 return; 54 if (IS_ENABLED(CONFIG_COMMON_CLK)) { 55 clk_set_rate(atmel_ehci->uclk, 48000000); 56 clk_prepare_enable(atmel_ehci->uclk); 57 } 58 clk_prepare_enable(atmel_ehci->iclk); 59 clk_prepare_enable(atmel_ehci->fclk); 60 atmel_ehci->clocked = true; 61 } 62 63 static void atmel_stop_clock(struct atmel_ehci_priv *atmel_ehci) 64 { 65 if (!atmel_ehci->clocked) 66 return; 67 clk_disable_unprepare(atmel_ehci->fclk); 68 clk_disable_unprepare(atmel_ehci->iclk); 69 if (IS_ENABLED(CONFIG_COMMON_CLK)) 70 clk_disable_unprepare(atmel_ehci->uclk); 71 atmel_ehci->clocked = false; 72 } 73 74 static void atmel_start_ehci(struct platform_device *pdev) 75 { 76 struct usb_hcd *hcd = platform_get_drvdata(pdev); 77 struct atmel_ehci_priv *atmel_ehci = hcd_to_atmel_ehci_priv(hcd); 78 79 dev_dbg(&pdev->dev, "start\n"); 80 atmel_start_clock(atmel_ehci); 81 } 82 83 static void atmel_stop_ehci(struct platform_device *pdev) 84 { 85 struct usb_hcd *hcd = platform_get_drvdata(pdev); 86 struct atmel_ehci_priv *atmel_ehci = hcd_to_atmel_ehci_priv(hcd); 87 88 dev_dbg(&pdev->dev, "stop\n"); 89 atmel_stop_clock(atmel_ehci); 90 } 91 92 /*-------------------------------------------------------------------------*/ 93 94 static int ehci_atmel_drv_probe(struct platform_device *pdev) 95 { 96 struct usb_hcd *hcd; 97 const struct hc_driver *driver = &ehci_atmel_hc_driver; 98 struct resource *res; 99 struct ehci_hcd *ehci; 100 struct atmel_ehci_priv *atmel_ehci; 101 int irq; 102 int retval; 103 104 if (usb_disabled()) 105 return -ENODEV; 106 107 pr_debug("Initializing Atmel-SoC USB Host Controller\n"); 108 109 irq = platform_get_irq(pdev, 0); 110 if (irq <= 0) { 111 dev_err(&pdev->dev, 112 "Found HC with no IRQ. Check %s setup!\n", 113 dev_name(&pdev->dev)); 114 retval = -ENODEV; 115 goto fail_create_hcd; 116 } 117 118 /* Right now device-tree probed devices don't get dma_mask set. 119 * Since shared usb code relies on it, set it here for now. 120 * Once we have dma capability bindings this can go away. 121 */ 122 retval = dma_coerce_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32)); 123 if (retval) 124 goto fail_create_hcd; 125 126 hcd = usb_create_hcd(driver, &pdev->dev, dev_name(&pdev->dev)); 127 if (!hcd) { 128 retval = -ENOMEM; 129 goto fail_create_hcd; 130 } 131 atmel_ehci = hcd_to_atmel_ehci_priv(hcd); 132 133 res = platform_get_resource(pdev, IORESOURCE_MEM, 0); 134 hcd->regs = devm_ioremap_resource(&pdev->dev, res); 135 if (IS_ERR(hcd->regs)) { 136 retval = PTR_ERR(hcd->regs); 137 goto fail_request_resource; 138 } 139 140 hcd->rsrc_start = res->start; 141 hcd->rsrc_len = resource_size(res); 142 143 atmel_ehci->iclk = devm_clk_get(&pdev->dev, "ehci_clk"); 144 if (IS_ERR(atmel_ehci->iclk)) { 145 dev_err(&pdev->dev, "Error getting interface clock\n"); 146 retval = -ENOENT; 147 goto fail_request_resource; 148 } 149 atmel_ehci->fclk = devm_clk_get(&pdev->dev, "uhpck"); 150 if (IS_ERR(atmel_ehci->fclk)) { 151 dev_err(&pdev->dev, "Error getting function clock\n"); 152 retval = -ENOENT; 153 goto fail_request_resource; 154 } 155 if (IS_ENABLED(CONFIG_COMMON_CLK)) { 156 atmel_ehci->uclk = devm_clk_get(&pdev->dev, "usb_clk"); 157 if (IS_ERR(atmel_ehci->uclk)) { 158 dev_err(&pdev->dev, "failed to get uclk\n"); 159 retval = PTR_ERR(atmel_ehci->uclk); 160 goto fail_request_resource; 161 } 162 } 163 164 ehci = hcd_to_ehci(hcd); 165 /* registers start at offset 0x0 */ 166 ehci->caps = hcd->regs; 167 168 atmel_start_ehci(pdev); 169 170 retval = usb_add_hcd(hcd, irq, IRQF_SHARED); 171 if (retval) 172 goto fail_add_hcd; 173 device_wakeup_enable(hcd->self.controller); 174 175 return retval; 176 177 fail_add_hcd: 178 atmel_stop_ehci(pdev); 179 fail_request_resource: 180 usb_put_hcd(hcd); 181 fail_create_hcd: 182 dev_err(&pdev->dev, "init %s fail, %d\n", 183 dev_name(&pdev->dev), retval); 184 185 return retval; 186 } 187 188 static int ehci_atmel_drv_remove(struct platform_device *pdev) 189 { 190 struct usb_hcd *hcd = platform_get_drvdata(pdev); 191 192 usb_remove_hcd(hcd); 193 usb_put_hcd(hcd); 194 195 atmel_stop_ehci(pdev); 196 197 return 0; 198 } 199 200 #ifdef CONFIG_PM 201 static int ehci_atmel_drv_suspend(struct device *dev) 202 { 203 struct usb_hcd *hcd = dev_get_drvdata(dev); 204 struct atmel_ehci_priv *atmel_ehci = hcd_to_atmel_ehci_priv(hcd); 205 int ret; 206 207 ret = ehci_suspend(hcd, false); 208 if (ret) 209 return ret; 210 211 atmel_stop_clock(atmel_ehci); 212 return 0; 213 } 214 215 static int ehci_atmel_drv_resume(struct device *dev) 216 { 217 struct usb_hcd *hcd = dev_get_drvdata(dev); 218 struct atmel_ehci_priv *atmel_ehci = hcd_to_atmel_ehci_priv(hcd); 219 220 atmel_start_clock(atmel_ehci); 221 return ehci_resume(hcd, false); 222 } 223 #endif 224 225 #ifdef CONFIG_OF 226 static const struct of_device_id atmel_ehci_dt_ids[] = { 227 { .compatible = "atmel,at91sam9g45-ehci" }, 228 { /* sentinel */ } 229 }; 230 231 MODULE_DEVICE_TABLE(of, atmel_ehci_dt_ids); 232 #endif 233 234 static SIMPLE_DEV_PM_OPS(ehci_atmel_pm_ops, ehci_atmel_drv_suspend, 235 ehci_atmel_drv_resume); 236 237 static struct platform_driver ehci_atmel_driver = { 238 .probe = ehci_atmel_drv_probe, 239 .remove = ehci_atmel_drv_remove, 240 .shutdown = usb_hcd_platform_shutdown, 241 .driver = { 242 .name = "atmel-ehci", 243 .pm = &ehci_atmel_pm_ops, 244 .of_match_table = of_match_ptr(atmel_ehci_dt_ids), 245 }, 246 }; 247 248 static int __init ehci_atmel_init(void) 249 { 250 if (usb_disabled()) 251 return -ENODEV; 252 253 pr_info("%s: " DRIVER_DESC "\n", hcd_name); 254 ehci_init_driver(&ehci_atmel_hc_driver, &ehci_atmel_drv_overrides); 255 return platform_driver_register(&ehci_atmel_driver); 256 } 257 module_init(ehci_atmel_init); 258 259 static void __exit ehci_atmel_cleanup(void) 260 { 261 platform_driver_unregister(&ehci_atmel_driver); 262 } 263 module_exit(ehci_atmel_cleanup); 264 265 MODULE_DESCRIPTION(DRIVER_DESC); 266 MODULE_ALIAS("platform:atmel-ehci"); 267 MODULE_AUTHOR("Nicolas Ferre"); 268 MODULE_LICENSE("GPL"); 269