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
  17 /* interface and function clocks */
  18 static struct clk *iclk, *fclk;
  19 static int clocked;
  20
  21 /*-------------------------------------------------------------------------*/
  22
  23 static void atmel_start_clock(void)
  24 {
  25         clk_enable(iclk);
  26         clk_enable(fclk);
  27         clocked = 1;
  28 }
  29
  30 static void atmel_stop_clock(void)
  31 {
  32         clk_disable(fclk);
  33         clk_disable(iclk);
  34         clocked = 0;
  35 }
  36
  37 static void atmel_start_ehci(struct platform_device *pdev)
  38 {
  39         dev_dbg(&pdev->dev, "start\n");
  40         atmel_start_clock();
  41 }
  42
  43 static void atmel_stop_ehci(struct platform_device *pdev)
  44 {
  45         dev_dbg(&pdev->dev, "stop\n");
  46         atmel_stop_clock();
  47 }
  48
  49 /*-------------------------------------------------------------------------*/
  50
  51 static int ehci_atmel_setup(struct usb_hcd *hcd)
  52 {
  53         struct ehci_hcd *ehci = hcd_to_ehci(hcd);
  54         int retval = 0;
  55
  56         /* registers start at offset 0x0 */
  57         ehci->caps = hcd->regs;
  58         ehci->regs = hcd->regs +
  59                 HC_LENGTH(ehci_readl(ehci, &ehci->caps->hc_capbase));
  60         dbg_hcs_params(ehci, "reset");
  61         dbg_hcc_params(ehci, "reset");
  62
  63         /* cache this readonly data; minimize chip reads */
  64         ehci->hcs_params = ehci_readl(ehci, &ehci->caps->hcs_params);
  65
  66         retval = ehci_halt(ehci);
  67         if (retval)
  68                 return retval;
  69
  70         /* data structure init */
  71         retval = ehci_init(hcd);
  72         if (retval)
  73                 return retval;
  74
  75         ehci->sbrn = 0x20;
  76
  77         ehci_reset(ehci);
  78         ehci_port_power(ehci, 0);
  79
  80         return retval;
  81 }
  82
  83 static const struct hc_driver ehci_atmel_hc_driver = {
  84         .description            = hcd_name,
  85         .product_desc           = "Atmel EHCI UHP HS",
  86         .hcd_priv_size          = sizeof(struct ehci_hcd),
  87
  88         /* generic hardware linkage */
  89         .irq                    = ehci_irq,
  90         .flags                  = HCD_MEMORY | HCD_USB2,
  91
  92         /* basic lifecycle operations */
  93         .reset                  = ehci_atmel_setup,
  94         .start                  = ehci_run,
  95         .stop                   = ehci_stop,
  96         .shutdown               = ehci_shutdown,
  97
  98         /* managing i/o requests and associated device resources */
  99         .urb_enqueue            = ehci_urb_enqueue,
 100         .urb_dequeue            = ehci_urb_dequeue,
 101         .endpoint_disable       = ehci_endpoint_disable,
 102
 103         /* scheduling support */
 104         .get_frame_number       = ehci_get_frame,
 105
 106         /* root hub support */
 107         .hub_status_data        = ehci_hub_status_data,
 108         .hub_control            = ehci_hub_control,
 109         .bus_suspend            = ehci_bus_suspend,
 110         .bus_resume             = ehci_bus_resume,
 111         .relinquish_port        = ehci_relinquish_port,
 112         .port_handed_over       = ehci_port_handed_over,
 113 };
 114
 115 static int __init ehci_atmel_drv_probe(struct platform_device *pdev)
 116 {
 117         struct usb_hcd *hcd;
 118         const struct hc_driver *driver = &ehci_atmel_hc_driver;
 119         struct resource *res;
 120         int irq;
 121         int retval;
 122
 123         if (usb_disabled())
 124                 return -ENODEV;
 125
 126         pr_debug("Initializing Atmel-SoC USB Host Controller\n");
 127
 128         irq = platform_get_irq(pdev, 0);
 129         if (irq <= 0) {
 130                 dev_err(&pdev->dev,
 131                         "Found HC with no IRQ. Check %s setup!\n",
 132                         dev_name(&pdev->dev));
 133                 retval = -ENODEV;
 134                 goto fail_create_hcd;
 135         }
 136
 137         hcd = usb_create_hcd(driver, &pdev->dev, dev_name(&pdev->dev));
 138         if (!hcd) {
 139                 retval = -ENOMEM;
 140                 goto fail_create_hcd;
 141         }
 142
 143         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 144         if (!res) {
 145                 dev_err(&pdev->dev,
 146                         "Found HC with no register addr. Check %s setup!\n",
 147                         dev_name(&pdev->dev));
 148                 retval = -ENODEV;
 149                 goto fail_request_resource;
 150         }
 151         hcd->rsrc_start = res->start;
 152         hcd->rsrc_len = res->end - res->start + 1;
 153
 154         if (!request_mem_region(hcd->rsrc_start, hcd->rsrc_len,
 155                                 driver->description)) {
 156                 dev_dbg(&pdev->dev, "controller already in use\n");
 157                 retval = -EBUSY;
 158                 goto fail_request_resource;
 159         }
 160
 161         hcd->regs = ioremap_nocache(hcd->rsrc_start, hcd->rsrc_len);
 162         if (hcd->regs == NULL) {
 163                 dev_dbg(&pdev->dev, "error mapping memory\n");
 164                 retval = -EFAULT;
 165                 goto fail_ioremap;
 166         }
 167
 168         iclk = clk_get(&pdev->dev, "ehci_clk");
 169         if (IS_ERR(iclk)) {
 170                 dev_err(&pdev->dev, "Error getting interface clock\n");
 171                 retval = -ENOENT;
 172                 goto fail_get_iclk;
 173         }
 174         fclk = clk_get(&pdev->dev, "uhpck");
 175         if (IS_ERR(fclk)) {
 176                 dev_err(&pdev->dev, "Error getting function clock\n");
 177                 retval = -ENOENT;
 178                 goto fail_get_fclk;
 179         }
 180
 181         atmel_start_ehci(pdev);
 182
 183         retval = usb_add_hcd(hcd, irq, IRQF_SHARED);
 184         if (retval)
 185                 goto fail_add_hcd;
 186
 187         return retval;
 188
 189 fail_add_hcd:
 190         atmel_stop_ehci(pdev);
 191         clk_put(fclk);
 192 fail_get_fclk:
 193         clk_put(iclk);
 194 fail_get_iclk:
 195         iounmap(hcd->regs);
 196 fail_ioremap:
 197         release_mem_region(hcd->rsrc_start, hcd->rsrc_len);
 198 fail_request_resource:
 199         usb_put_hcd(hcd);
 200 fail_create_hcd:
 201         dev_err(&pdev->dev, "init %s fail, %d\n",
 202                 dev_name(&pdev->dev), retval);
 203
 204         return retval;
 205 }
 206
 207 static int __exit ehci_atmel_drv_remove(struct platform_device *pdev)
 208 {
 209         struct usb_hcd *hcd = platform_get_drvdata(pdev);
 210
 211         ehci_shutdown(hcd);
 212         usb_remove_hcd(hcd);
 213         iounmap(hcd->regs);
 214         release_mem_region(hcd->rsrc_start, hcd->rsrc_len);
 215         usb_put_hcd(hcd);
 216
 217         atmel_stop_ehci(pdev);
 218         clk_put(fclk);
 219         clk_put(iclk);
 220         fclk = iclk = NULL;
 221
 222         return 0;
 223 }
 224
 225 static struct platform_driver ehci_atmel_driver = {
 226         .probe          = ehci_atmel_drv_probe,
 227         .remove         = __exit_p(ehci_atmel_drv_remove),
 228         .shutdown       = usb_hcd_platform_shutdown,
 229         .driver.name    = "atmel-ehci",
 230 };