drivers/usb/host/ehci-atmel.c

   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/platform_device.h>
  16 #include <linux/of.h>
  17 #include <linux/of_platform.h>
  18
  19 /* interface and function clocks */
  20 static struct clk *iclk, *fclk;
  21 static int clocked;
  22
  23 /*-------------------------------------------------------------------------*/
  24
  25 static void atmel_start_clock(void)
  26 {
  27         clk_enable(iclk);
  28         clk_enable(fclk);
  29         clocked = 1;
  30 }
  31
  32 static void atmel_stop_clock(void)
  33 {
  34         clk_disable(fclk);
  35         clk_disable(iclk);
  36         clocked = 0;
  37 }
  38
  39 static void atmel_start_ehci(struct platform_device *pdev)
  40 {
  41         dev_dbg(&pdev->dev, "start\n");
  42         atmel_start_clock();
  43 }
  44
  45 static void atmel_stop_ehci(struct platform_device *pdev)
  46 {
  47         dev_dbg(&pdev->dev, "stop\n");
  48         atmel_stop_clock();
  49 }
  50
  51 /*-------------------------------------------------------------------------*/
  52
  53 static int ehci_atmel_setup(struct usb_hcd *hcd)
  54 {
  55         struct ehci_hcd *ehci = hcd_to_ehci(hcd);
  56
  57         /* registers start at offset 0x0 */
  58         ehci->caps = hcd->regs;
  59
  60         return ehci_setup(hcd);
  61 }
  62
  63 static const struct hc_driver ehci_atmel_hc_driver = {
  64         .description            = hcd_name,
  65         .product_desc           = "Atmel EHCI UHP HS",
  66         .hcd_priv_size          = sizeof(struct ehci_hcd),
  67
  68         /* generic hardware linkage */
  69         .irq                    = ehci_irq,
  70         .flags                  = HCD_MEMORY | HCD_USB2,
  71
  72         /* basic lifecycle operations */
  73         .reset                  = ehci_atmel_setup,
  74         .start                  = ehci_run,
  75         .stop                   = ehci_stop,
  76         .shutdown               = ehci_shutdown,
  77
  78         /* managing i/o requests and associated device resources */
  79         .urb_enqueue            = ehci_urb_enqueue,
  80         .urb_dequeue            = ehci_urb_dequeue,
  81         .endpoint_disable       = ehci_endpoint_disable,
  82         .endpoint_reset         = ehci_endpoint_reset,
  83
  84         /* scheduling support */
  85         .get_frame_number       = ehci_get_frame,
  86
  87         /* root hub support */
  88         .hub_status_data        = ehci_hub_status_data,
  89         .hub_control            = ehci_hub_control,
  90         .bus_suspend            = ehci_bus_suspend,
  91         .bus_resume             = ehci_bus_resume,
  92         .relinquish_port        = ehci_relinquish_port,
  93         .port_handed_over       = ehci_port_handed_over,
  94
  95         .clear_tt_buffer_complete       = ehci_clear_tt_buffer_complete,
  96 };
  97
  98 static u64 at91_ehci_dma_mask = DMA_BIT_MASK(32);
  99
 100 static int ehci_atmel_drv_probe(struct platform_device *pdev)
 101 {
 102         struct usb_hcd *hcd;
 103         const struct hc_driver *driver = &ehci_atmel_hc_driver;
 104         struct resource *res;
 105         int irq;
 106         int retval;
 107
 108         if (usb_disabled())
 109                 return -ENODEV;
 110
 111         pr_debug("Initializing Atmel-SoC USB Host Controller\n");
 112
 113         irq = platform_get_irq(pdev, 0);
 114         if (irq <= 0) {
 115                 dev_err(&pdev->dev,
 116                         "Found HC with no IRQ. Check %s setup!\n",
 117                         dev_name(&pdev->dev));
 118                 retval = -ENODEV;
 119                 goto fail_create_hcd;
 120         }
 121
 122         /* Right now device-tree probed devices don't get dma_mask set.
 123          * Since shared usb code relies on it, set it here for now.
 124          * Once we have dma capability bindings this can go away.
 125          */
 126         if (!pdev->dev.dma_mask)
 127                 pdev->dev.dma_mask = &at91_ehci_dma_mask;
 128
 129         hcd = usb_create_hcd(driver, &pdev->dev, dev_name(&pdev->dev));
 130         if (!hcd) {
 131                 retval = -ENOMEM;
 132                 goto fail_create_hcd;
 133         }
 134
 135         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 136         if (!res) {
 137                 dev_err(&pdev->dev,
 138                         "Found HC with no register addr. Check %s setup!\n",
 139                         dev_name(&pdev->dev));
 140                 retval = -ENODEV;
 141                 goto fail_request_resource;
 142         }
 143         hcd->rsrc_start = res->start;
 144         hcd->rsrc_len = resource_size(res);
 145
 146         hcd->regs = devm_ioremap_resource(&pdev->dev, res);
 147         if (IS_ERR(hcd->regs)) {
 148                 retval = PTR_ERR(hcd->regs);
 149                 goto fail_request_resource;
 150         }
 151
 152         iclk = devm_clk_get(&pdev->dev, "ehci_clk");
 153         if (IS_ERR(iclk)) {
 154                 dev_err(&pdev->dev, "Error getting interface clock\n");
 155                 retval = -ENOENT;
 156                 goto fail_request_resource;
 157         }
 158         fclk = devm_clk_get(&pdev->dev, "uhpck");
 159         if (IS_ERR(fclk)) {
 160                 dev_err(&pdev->dev, "Error getting function clock\n");
 161                 retval = -ENOENT;
 162                 goto fail_request_resource;
 163         }
 164
 165         atmel_start_ehci(pdev);
 166
 167         retval = usb_add_hcd(hcd, irq, IRQF_SHARED);
 168         if (retval)
 169                 goto fail_add_hcd;
 170
 171         return retval;
 172
 173 fail_add_hcd:
 174         atmel_stop_ehci(pdev);
 175 fail_request_resource:
 176         usb_put_hcd(hcd);
 177 fail_create_hcd:
 178         dev_err(&pdev->dev, "init %s fail, %d\n",
 179                 dev_name(&pdev->dev), retval);
 180
 181         return retval;
 182 }
 183
 184 static int ehci_atmel_drv_remove(struct platform_device *pdev)
 185 {
 186         struct usb_hcd *hcd = platform_get_drvdata(pdev);
 187
 188         ehci_shutdown(hcd);
 189         usb_remove_hcd(hcd);
 190         usb_put_hcd(hcd);
 191
 192         atmel_stop_ehci(pdev);
 193         fclk = iclk = NULL;
 194
 195         return 0;
 196 }
 197
 198 #ifdef CONFIG_OF
 199 static const struct of_device_id atmel_ehci_dt_ids[] = {
 200         { .compatible = "atmel,at91sam9g45-ehci" },
 201         { /* sentinel */ }
 202 };
 203
 204 MODULE_DEVICE_TABLE(of, atmel_ehci_dt_ids);
 205 #endif
 206
 207 static struct platform_driver ehci_atmel_driver = {
 208         .probe          = ehci_atmel_drv_probe,
 209         .remove         = ehci_atmel_drv_remove,
 210         .shutdown       = usb_hcd_platform_shutdown,
 211         .driver         = {
 212                 .name   = "atmel-ehci",
 213                 .of_match_table = of_match_ptr(atmel_ehci_dt_ids),
 214         },
 215 };