| 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 *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 | |
| 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 | |
| 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 | |
| 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 | |
| 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 | |
| 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 | dev_err(&pdev->dev, |
| 107 | "Found HC with no IRQ. Check %s setup!\n", |
| 108 | dev_name(&pdev->dev)); |
| 109 | retval = -ENODEV; |
| 110 | goto fail_create_hcd; |
| 111 | } |
| 112 | |
| 113 | /* Right now device-tree probed devices don't get dma_mask set. |
| 114 | * Since shared usb code relies on it, set it here for now. |
| 115 | * Once we have dma capability bindings this can go away. |
| 116 | */ |
| 117 | retval = dma_coerce_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32)); |
| 118 | if (retval) |
| 119 | goto fail_create_hcd; |
| 120 | |
| 121 | hcd = usb_create_hcd(driver, &pdev->dev, dev_name(&pdev->dev)); |
| 122 | if (!hcd) { |
| 123 | retval = -ENOMEM; |
| 124 | goto fail_create_hcd; |
| 125 | } |
| 126 | atmel_ehci = hcd_to_atmel_ehci_priv(hcd); |
| 127 | |
| 128 | res = platform_get_resource(pdev, IORESOURCE_MEM, 0); |
| 129 | hcd->regs = devm_ioremap_resource(&pdev->dev, res); |
| 130 | if (IS_ERR(hcd->regs)) { |
| 131 | retval = PTR_ERR(hcd->regs); |
| 132 | goto fail_request_resource; |
| 133 | } |
| 134 | |
| 135 | hcd->rsrc_start = res->start; |
| 136 | hcd->rsrc_len = resource_size(res); |
| 137 | |
| 138 | atmel_ehci->iclk = devm_clk_get(&pdev->dev, "ehci_clk"); |
| 139 | if (IS_ERR(atmel_ehci->iclk)) { |
| 140 | dev_err(&pdev->dev, "Error getting interface clock\n"); |
| 141 | retval = -ENOENT; |
| 142 | goto fail_request_resource; |
| 143 | } |
| 144 | |
| 145 | atmel_ehci->uclk = devm_clk_get(&pdev->dev, "usb_clk"); |
| 146 | if (IS_ERR(atmel_ehci->uclk)) { |
| 147 | dev_err(&pdev->dev, "failed to get uclk\n"); |
| 148 | retval = PTR_ERR(atmel_ehci->uclk); |
| 149 | goto fail_request_resource; |
| 150 | } |
| 151 | |
| 152 | ehci = hcd_to_ehci(hcd); |
| 153 | /* registers start at offset 0x0 */ |
| 154 | ehci->caps = hcd->regs; |
| 155 | |
| 156 | atmel_start_ehci(pdev); |
| 157 | |
| 158 | retval = usb_add_hcd(hcd, irq, IRQF_SHARED); |
| 159 | if (retval) |
| 160 | goto fail_add_hcd; |
| 161 | device_wakeup_enable(hcd->self.controller); |
| 162 | |
| 163 | return retval; |
| 164 | |
| 165 | fail_add_hcd: |
| 166 | atmel_stop_ehci(pdev); |
| 167 | fail_request_resource: |
| 168 | usb_put_hcd(hcd); |
| 169 | fail_create_hcd: |
| 170 | dev_err(&pdev->dev, "init %s fail, %d\n", |
| 171 | dev_name(&pdev->dev), retval); |
| 172 | |
| 173 | return retval; |
| 174 | } |
| 175 | |
| 176 | static int ehci_atmel_drv_remove(struct platform_device *pdev) |
| 177 | { |
| 178 | struct usb_hcd *hcd = platform_get_drvdata(pdev); |
| 179 | |
| 180 | usb_remove_hcd(hcd); |
| 181 | usb_put_hcd(hcd); |
| 182 | |
| 183 | atmel_stop_ehci(pdev); |
| 184 | |
| 185 | return 0; |
| 186 | } |
| 187 | |
| 188 | static int __maybe_unused ehci_atmel_drv_suspend(struct device *dev) |
| 189 | { |
| 190 | struct usb_hcd *hcd = dev_get_drvdata(dev); |
| 191 | struct atmel_ehci_priv *atmel_ehci = hcd_to_atmel_ehci_priv(hcd); |
| 192 | int ret; |
| 193 | |
| 194 | ret = ehci_suspend(hcd, false); |
| 195 | if (ret) |
| 196 | return ret; |
| 197 | |
| 198 | atmel_stop_clock(atmel_ehci); |
| 199 | return 0; |
| 200 | } |
| 201 | |
| 202 | static int __maybe_unused ehci_atmel_drv_resume(struct device *dev) |
| 203 | { |
| 204 | struct usb_hcd *hcd = dev_get_drvdata(dev); |
| 205 | struct atmel_ehci_priv *atmel_ehci = hcd_to_atmel_ehci_priv(hcd); |
| 206 | |
| 207 | atmel_start_clock(atmel_ehci); |
| 208 | return ehci_resume(hcd, false); |
| 209 | } |
| 210 | |
| 211 | #ifdef CONFIG_OF |
| 212 | static const struct of_device_id atmel_ehci_dt_ids[] = { |
| 213 | { .compatible = "atmel,at91sam9g45-ehci" }, |
| 214 | { /* sentinel */ } |
| 215 | }; |
| 216 | |
| 217 | MODULE_DEVICE_TABLE(of, atmel_ehci_dt_ids); |
| 218 | #endif |
| 219 | |
| 220 | static SIMPLE_DEV_PM_OPS(ehci_atmel_pm_ops, ehci_atmel_drv_suspend, |
| 221 | ehci_atmel_drv_resume); |
| 222 | |
| 223 | static struct platform_driver ehci_atmel_driver = { |
| 224 | .probe = ehci_atmel_drv_probe, |
| 225 | .remove = ehci_atmel_drv_remove, |
| 226 | .shutdown = usb_hcd_platform_shutdown, |
| 227 | .driver = { |
| 228 | .name = "atmel-ehci", |
| 229 | .pm = &ehci_atmel_pm_ops, |
| 230 | .of_match_table = of_match_ptr(atmel_ehci_dt_ids), |
| 231 | }, |
| 232 | }; |
| 233 | |
| 234 | static int __init ehci_atmel_init(void) |
| 235 | { |
| 236 | if (usb_disabled()) |
| 237 | return -ENODEV; |
| 238 | |
| 239 | pr_info("%s: " DRIVER_DESC "\n", hcd_name); |
| 240 | ehci_init_driver(&ehci_atmel_hc_driver, &ehci_atmel_drv_overrides); |
| 241 | return platform_driver_register(&ehci_atmel_driver); |
| 242 | } |
| 243 | module_init(ehci_atmel_init); |
| 244 | |
| 245 | static void __exit ehci_atmel_cleanup(void) |
| 246 | { |
| 247 | platform_driver_unregister(&ehci_atmel_driver); |
| 248 | } |
| 249 | module_exit(ehci_atmel_cleanup); |
| 250 | |
| 251 | MODULE_DESCRIPTION(DRIVER_DESC); |
| 252 | MODULE_ALIAS("platform:atmel-ehci"); |
| 253 | MODULE_AUTHOR("Nicolas Ferre"); |
| 254 | MODULE_LICENSE("GPL"); |