ohci-at91.c

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/*
 * OHCI HCD (Host Controller Driver) for USB.
 *
 *  Copyright (C) 2004 SAN People (Pty) Ltd.
 *  Copyright (C) 2005 Thibaut VARENE <[email protected]>
 *
 * AT91 Bus Glue
 *
 * Based on fragments of 2.4 driver by Rick Bronson.
 * Based on ohci-omap.c
 *
 * This file is licenced under the GPL.
 */

#include <linux/clk.h>
#include <linux/platform_device.h>
#include <linux/of_platform.h>
#include <linux/of_gpio.h>

#include <mach/hardware.h>
#include <asm/gpio.h>

#include <mach/board.h>
#include <mach/cpu.h>

#ifndef CONFIG_ARCH_AT91
#error "CONFIG_ARCH_AT91 must be defined."
#endif

#define valid_port(index)   ((index) >= 0 && (index) < AT91_MAX_USBH_PORTS)
#define at91_for_each_port(index)   \
        for ((index) = 0; (index) < AT91_MAX_USBH_PORTS; (index)++)

/* interface and function clocks; sometimes also an AHB clock */
static struct clk *iclk, *fclk, *hclk;
static int clocked;

extern int usb_disabled(void);

/*-------------------------------------------------------------------------*/

static void at91_start_clock(void)
{
    clk_enable(hclk);
    clk_enable(iclk);
    clk_enable(fclk);
    clocked = 1;
}

static void at91_stop_clock(void)
{
    clk_disable(fclk);
    clk_disable(iclk);
    clk_disable(hclk);
    clocked = 0;
}

static void at91_start_hc(struct platform_device *pdev)
{
    struct usb_hcd *hcd = platform_get_drvdata(pdev);
    struct ohci_regs __iomem *regs = hcd->regs;

    dev_dbg(&pdev->dev, "start\n");

    /*
     * Start the USB clocks.
     */
    at91_start_clock();

    /*
     * The USB host controller must remain in reset.
     */
    writel(0, &regs->control);
}

static void at91_stop_hc(struct platform_device *pdev)
{
    struct usb_hcd *hcd = platform_get_drvdata(pdev);
    struct ohci_regs __iomem *regs = hcd->regs;

    dev_dbg(&pdev->dev, "stop\n");

    /*
     * Put the USB host controller into reset.
     */
    writel(0, &regs->control);

    /*
     * Stop the USB clocks.
     */
    at91_stop_clock();
}


/*-------------------------------------------------------------------------*/

static void __devexit usb_hcd_at91_remove (struct usb_hcd *, struct platform_device *);

/* configure so an HC device and id are always provided */
/* always called with process context; sleeping is OK */


static int __devinit usb_hcd_at91_probe(const struct hc_driver *driver,
            struct platform_device *pdev)
{
    int retval;
    struct usb_hcd *hcd = NULL;

    if (pdev->num_resources != 2) {
        pr_debug("hcd probe: invalid num_resources");
        return -ENODEV;
    }

    if ((pdev->resource[0].flags != IORESOURCE_MEM)
            || (pdev->resource[1].flags != IORESOURCE_IRQ)) {
        pr_debug("hcd probe: invalid resource type\n");
        return -ENODEV;
    }

    hcd = usb_create_hcd(driver, &pdev->dev, "at91");
    if (!hcd)
        return -ENOMEM;
    hcd->rsrc_start = pdev->resource[0].start;
    hcd->rsrc_len = resource_size(&pdev->resource[0]);

    if (!request_mem_region(hcd->rsrc_start, hcd->rsrc_len, hcd_name)) {
        pr_debug("request_mem_region failed\n");
        retval = -EBUSY;
        goto err1;
    }

    hcd->regs = ioremap(hcd->rsrc_start, hcd->rsrc_len);
    if (!hcd->regs) {
        pr_debug("ioremap failed\n");
        retval = -EIO;
        goto err2;
    }

    iclk = clk_get(&pdev->dev, "ohci_clk");
    if (IS_ERR(iclk)) {
        dev_err(&pdev->dev, "failed to get ohci_clk\n");
        retval = PTR_ERR(iclk);
        goto err3;
    }
    fclk = clk_get(&pdev->dev, "uhpck");
    if (IS_ERR(fclk)) {
        dev_err(&pdev->dev, "failed to get uhpck\n");
        retval = PTR_ERR(fclk);
        goto err4;
    }
    hclk = clk_get(&pdev->dev, "hclk");
    if (IS_ERR(hclk)) {
        dev_err(&pdev->dev, "failed to get hclk\n");
        retval = PTR_ERR(hclk);
        goto err5;
    }

    at91_start_hc(pdev);
    ohci_hcd_init(hcd_to_ohci(hcd));

    retval = usb_add_hcd(hcd, pdev->resource[1].start, IRQF_SHARED);
    if (retval == 0)
        return retval;

    /* Error handling */
    at91_stop_hc(pdev);

    clk_put(hclk);
 err5:
    clk_put(fclk);
 err4:
    clk_put(iclk);

 err3:
    iounmap(hcd->regs);

 err2:
    release_mem_region(hcd->rsrc_start, hcd->rsrc_len);

 err1:
    usb_put_hcd(hcd);
    return retval;
}


/* may be called with controller, bus, and devices active */

static void __devexit usb_hcd_at91_remove(struct usb_hcd *hcd,
                struct platform_device *pdev)
{
    usb_remove_hcd(hcd);
    at91_stop_hc(pdev);
    iounmap(hcd->regs);
    release_mem_region(hcd->rsrc_start, hcd->rsrc_len);
    usb_put_hcd(hcd);

    clk_put(hclk);
    clk_put(fclk);
    clk_put(iclk);
    fclk = iclk = hclk = NULL;

    dev_set_drvdata(&pdev->dev, NULL);
}

/*-------------------------------------------------------------------------*/

static int __devinit
ohci_at91_reset (struct usb_hcd *hcd)
{
    struct at91_usbh_data   *board = hcd->self.controller->platform_data;
    struct ohci_hcd     *ohci = hcd_to_ohci (hcd);
    int         ret;

    if ((ret = ohci_init(ohci)) < 0)
        return ret;

    ohci->num_ports = board->ports;
    return 0;
}

static int __devinit
ohci_at91_start (struct usb_hcd *hcd)
{
    struct ohci_hcd     *ohci = hcd_to_ohci (hcd);
    int         ret;

    if ((ret = ohci_run(ohci)) < 0) {
        dev_err(hcd->self.controller, "can't start %s\n",
            hcd->self.bus_name);
        ohci_stop(hcd);
        return ret;
    }
    return 0;
}

static void ohci_at91_usb_set_power(struct at91_usbh_data *pdata, int port, int enable)
{
    if (!valid_port(port))
        return;

    if (!gpio_is_valid(pdata->vbus_pin[port]))
        return;

    gpio_set_value(pdata->vbus_pin[port],
               pdata->vbus_pin_active_low[port] ^ enable);
}

static int ohci_at91_usb_get_power(struct at91_usbh_data *pdata, int port)
{
    if (!valid_port(port))
        return -EINVAL;

    if (!gpio_is_valid(pdata->vbus_pin[port]))
        return -EINVAL;

    return gpio_get_value(pdata->vbus_pin[port]) ^
        pdata->vbus_pin_active_low[port];
}

/*
 * Update the status data from the hub with the over-current indicator change.
 */
static int ohci_at91_hub_status_data(struct usb_hcd *hcd, char *buf)
{
    struct at91_usbh_data *pdata = hcd->self.controller->platform_data;
    int length = ohci_hub_status_data(hcd, buf);
    int port;

    at91_for_each_port(port) {
        if (pdata->overcurrent_changed[port]) {
            if (!length)
                length = 1;
            buf[0] |= 1 << (port + 1);
        }
    }

    return length;
}

/*
 * Look at the control requests to the root hub and see if we need to override.
 */
static int ohci_at91_hub_control(struct usb_hcd *hcd, u16 typeReq, u16 wValue,
                 u16 wIndex, char *buf, u16 wLength)
{
    struct at91_usbh_data *pdata = hcd->self.controller->platform_data;
    struct usb_hub_descriptor *desc;
    int ret = -EINVAL;
    u32 *data = (u32 *)buf;

    dev_dbg(hcd->self.controller,
        "ohci_at91_hub_control(%p,0x%04x,0x%04x,0x%04x,%p,%04x)\n",
        hcd, typeReq, wValue, wIndex, buf, wLength);

    wIndex--;

    switch (typeReq) {
    case SetPortFeature:
        if (wValue == USB_PORT_FEAT_POWER) {
            dev_dbg(hcd->self.controller, "SetPortFeat: POWER\n");
            if (valid_port(wIndex)) {
                ohci_at91_usb_set_power(pdata, wIndex, 1);
                ret = 0;
            }

            goto out;
        }
        break;

    case ClearPortFeature:
        switch (wValue) {
        case USB_PORT_FEAT_C_OVER_CURRENT:
            dev_dbg(hcd->self.controller,
                "ClearPortFeature: C_OVER_CURRENT\n");

            if (valid_port(wIndex)) {
                pdata->overcurrent_changed[wIndex] = 0;
                pdata->overcurrent_status[wIndex] = 0;
            }

            goto out;

        case USB_PORT_FEAT_OVER_CURRENT:
            dev_dbg(hcd->self.controller,
                "ClearPortFeature: OVER_CURRENT\n");

            if (valid_port(wIndex))
                pdata->overcurrent_status[wIndex] = 0;

            goto out;

        case USB_PORT_FEAT_POWER:
            dev_dbg(hcd->self.controller,
                "ClearPortFeature: POWER\n");

            if (valid_port(wIndex)) {
                ohci_at91_usb_set_power(pdata, wIndex, 0);
                return 0;
            }
        }
        break;
    }

    ret = ohci_hub_control(hcd, typeReq, wValue, wIndex + 1, buf, wLength);
    if (ret)
        goto out;

    switch (typeReq) {
    case GetHubDescriptor:

        /* update the hub's descriptor */

        desc = (struct usb_hub_descriptor *)buf;

        dev_dbg(hcd->self.controller, "wHubCharacteristics 0x%04x\n",
            desc->wHubCharacteristics);

        /* remove the old configurations for power-switching, and
         * over-current protection, and insert our new configuration
         */

        desc->wHubCharacteristics &= ~cpu_to_le16(HUB_CHAR_LPSM);
        desc->wHubCharacteristics |= cpu_to_le16(0x0001);

        if (pdata->overcurrent_supported) {
            desc->wHubCharacteristics &= ~cpu_to_le16(HUB_CHAR_OCPM);
            desc->wHubCharacteristics |=  cpu_to_le16(0x0008|0x0001);
        }

        dev_dbg(hcd->self.controller, "wHubCharacteristics after 0x%04x\n",
            desc->wHubCharacteristics);

        return ret;

    case GetPortStatus:
        /* check port status */

        dev_dbg(hcd->self.controller, "GetPortStatus(%d)\n", wIndex);

        if (valid_port(wIndex)) {
            if (!ohci_at91_usb_get_power(pdata, wIndex))
                *data &= ~cpu_to_le32(RH_PS_PPS);

            if (pdata->overcurrent_changed[wIndex])
                *data |= cpu_to_le32(RH_PS_OCIC);

            if (pdata->overcurrent_status[wIndex])
                *data |= cpu_to_le32(RH_PS_POCI);
        }
    }

 out:
    return ret;
}

/*-------------------------------------------------------------------------*/

static const struct hc_driver ohci_at91_hc_driver = {
    .description =      hcd_name,
    .product_desc =     "AT91 OHCI",
    .hcd_priv_size =    sizeof(struct ohci_hcd),

    /*
     * generic hardware linkage
     */
    .irq =          ohci_irq,
    .flags =        HCD_USB11 | HCD_MEMORY,

    /*
     * basic lifecycle operations
     */
    .reset =        ohci_at91_reset,
    .start =        ohci_at91_start,
    .stop =         ohci_stop,
    .shutdown =     ohci_shutdown,

    /*
     * managing i/o requests and associated device resources
     */
    .urb_enqueue =      ohci_urb_enqueue,
    .urb_dequeue =      ohci_urb_dequeue,
    .endpoint_disable = ohci_endpoint_disable,

    /*
     * scheduling support
     */
    .get_frame_number = ohci_get_frame,

    /*
     * root hub support
     */
    .hub_status_data =  ohci_at91_hub_status_data,
    .hub_control =      ohci_at91_hub_control,
#ifdef CONFIG_PM
    .bus_suspend =      ohci_bus_suspend,
    .bus_resume =       ohci_bus_resume,
#endif
    .start_port_reset = ohci_start_port_reset,
};

/*-------------------------------------------------------------------------*/

static irqreturn_t ohci_hcd_at91_overcurrent_irq(int irq, void *data)
{
    struct platform_device *pdev = data;
    struct at91_usbh_data *pdata = pdev->dev.platform_data;
    int val, gpio, port;

    /* From the GPIO notifying the over-current situation, find
     * out the corresponding port */
    at91_for_each_port(port) {
        if (gpio_is_valid(pdata->overcurrent_pin[port]) &&
                gpio_to_irq(pdata->overcurrent_pin[port]) == irq) {
            gpio = pdata->overcurrent_pin[port];
            break;
        }
    }

    if (port == AT91_MAX_USBH_PORTS) {
        dev_err(& pdev->dev, "overcurrent interrupt from unknown GPIO\n");
        return IRQ_HANDLED;
    }

    val = gpio_get_value(gpio);

    /* When notified of an over-current situation, disable power
       on the corresponding port, and mark this port in
       over-current. */
    if (!val) {
        ohci_at91_usb_set_power(pdata, port, 0);
        pdata->overcurrent_status[port]  = 1;
        pdata->overcurrent_changed[port] = 1;
    }

    dev_dbg(& pdev->dev, "overcurrent situation %s\n",
        val ? "exited" : "notified");

    return IRQ_HANDLED;
}

#ifdef CONFIG_OF
static const struct of_device_id at91_ohci_dt_ids[] = {
    { .compatible = "atmel,at91rm9200-ohci" },
    { /* sentinel */ }
};

MODULE_DEVICE_TABLE(of, at91_ohci_dt_ids);

static u64 at91_ohci_dma_mask = DMA_BIT_MASK(32);

static int __devinit ohci_at91_of_init(struct platform_device *pdev)
{
    struct device_node *np = pdev->dev.of_node;
    int i, gpio;
    enum of_gpio_flags flags;
    struct at91_usbh_data   *pdata;
    u32 ports;

    if (!np)
        return 0;

    /* Right now device-tree probed devices don't get dma_mask set.
     * Since shared usb code relies on it, set it here for now.
     * Once we have dma capability bindings this can go away.
     */
    if (!pdev->dev.dma_mask)
        pdev->dev.dma_mask = &at91_ohci_dma_mask;

    pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
    if (!pdata)
        return -ENOMEM;

    if (!of_property_read_u32(np, "num-ports", &ports))
        pdata->ports = ports;

    at91_for_each_port(i) {
        gpio = of_get_named_gpio_flags(np, "atmel,vbus-gpio", i, &flags);
        pdata->vbus_pin[i] = gpio;
        if (!gpio_is_valid(gpio))
            continue;
        pdata->vbus_pin_active_low[i] = flags & OF_GPIO_ACTIVE_LOW;
    }

    at91_for_each_port(i)
        pdata->overcurrent_pin[i] =
            of_get_named_gpio_flags(np, "atmel,oc-gpio", i, &flags);

    pdev->dev.platform_data = pdata;

    return 0;
}
#else
static int __devinit ohci_at91_of_init(struct platform_device *pdev)
{
    return 0;
}
#endif

/*-------------------------------------------------------------------------*/

static int __devinit ohci_hcd_at91_drv_probe(struct platform_device *pdev)
{
    struct at91_usbh_data   *pdata;
    int         i;
    int         gpio;
    int         ret;

    ret = ohci_at91_of_init(pdev);
    if (ret)
        return ret;

    pdata = pdev->dev.platform_data;

    if (pdata) {
        at91_for_each_port(i) {
            /*
             * do not configure PIO if not in relation with
             * real USB port on board
             */
            if (i >= pdata->ports) {
                pdata->vbus_pin[i] = -EINVAL;
                pdata->overcurrent_pin[i] = -EINVAL;
                break;
            }

            if (!gpio_is_valid(pdata->vbus_pin[i]))
                continue;
            gpio = pdata->vbus_pin[i];

            ret = gpio_request(gpio, "ohci_vbus");
            if (ret) {
                dev_err(&pdev->dev,
                    "can't request vbus gpio %d\n", gpio);
                continue;
            }
            ret = gpio_direction_output(gpio,
                        !pdata->vbus_pin_active_low[i]);
            if (ret) {
                dev_err(&pdev->dev,
                    "can't put vbus gpio %d as output %d\n",
                    gpio, !pdata->vbus_pin_active_low[i]);
                gpio_free(gpio);
                continue;
            }

            ohci_at91_usb_set_power(pdata, i, 1);
        }

        at91_for_each_port(i) {
            if (!gpio_is_valid(pdata->overcurrent_pin[i]))
                continue;
            gpio = pdata->overcurrent_pin[i];

            ret = gpio_request(gpio, "ohci_overcurrent");
            if (ret) {
                dev_err(&pdev->dev,
                    "can't request overcurrent gpio %d\n",
                    gpio);
                continue;
            }

            ret = gpio_direction_input(gpio);
            if (ret) {
                dev_err(&pdev->dev,
                    "can't configure overcurrent gpio %d as input\n",
                    gpio);
                gpio_free(gpio);
                continue;
            }

            ret = request_irq(gpio_to_irq(gpio),
                      ohci_hcd_at91_overcurrent_irq,
                      IRQF_SHARED, "ohci_overcurrent", pdev);
            if (ret) {
                gpio_free(gpio);
                dev_err(&pdev->dev,
                    "can't get gpio IRQ for overcurrent\n");
            }
        }
    }

    device_init_wakeup(&pdev->dev, 1);
    return usb_hcd_at91_probe(&ohci_at91_hc_driver, pdev);
}

static int __devexit ohci_hcd_at91_drv_remove(struct platform_device *pdev)
{
    struct at91_usbh_data   *pdata = pdev->dev.platform_data;
    int         i;

    if (pdata) {
        at91_for_each_port(i) {
            if (!gpio_is_valid(pdata->vbus_pin[i]))
                continue;
            ohci_at91_usb_set_power(pdata, i, 0);
            gpio_free(pdata->vbus_pin[i]);
        }

        at91_for_each_port(i) {
            if (!gpio_is_valid(pdata->overcurrent_pin[i]))
                continue;
            free_irq(gpio_to_irq(pdata->overcurrent_pin[i]), pdev);
            gpio_free(pdata->overcurrent_pin[i]);
        }
    }

    device_init_wakeup(&pdev->dev, 0);
    usb_hcd_at91_remove(platform_get_drvdata(pdev), pdev);
    return 0;
}

#ifdef CONFIG_PM

static int
ohci_hcd_at91_drv_suspend(struct platform_device *pdev, pm_message_t mesg)
{
    struct usb_hcd  *hcd = platform_get_drvdata(pdev);
    struct ohci_hcd *ohci = hcd_to_ohci(hcd);

    if (device_may_wakeup(&pdev->dev))
        enable_irq_wake(hcd->irq);

    /*
     * The integrated transceivers seem unable to notice disconnect,
     * reconnect, or wakeup without the 48 MHz clock active.  so for
     * correctness, always discard connection state (using reset).
     *
     * REVISIT: some boards will be able to turn VBUS off...
     */
    if (at91_suspend_entering_slow_clock()) {
        ohci_usb_reset (ohci);
        /* flush the writes */
        (void) ohci_readl (ohci, &ohci->regs->control);
        at91_stop_clock();
    }

    return 0;
}

static int ohci_hcd_at91_drv_resume(struct platform_device *pdev)
{
    struct usb_hcd  *hcd = platform_get_drvdata(pdev);

    if (device_may_wakeup(&pdev->dev))
        disable_irq_wake(hcd->irq);

    if (!clocked)
        at91_start_clock();

    ohci_finish_controller_resume(hcd);
    return 0;
}
#else
#define ohci_hcd_at91_drv_suspend NULL
#define ohci_hcd_at91_drv_resume  NULL
#endif

MODULE_ALIAS("platform:at91_ohci");

static struct platform_driver ohci_hcd_at91_driver = {
    .probe      = ohci_hcd_at91_drv_probe,
    .remove     = __devexit_p(ohci_hcd_at91_drv_remove),
    .shutdown   = usb_hcd_platform_shutdown,
    .suspend    = ohci_hcd_at91_drv_suspend,
    .resume     = ohci_hcd_at91_drv_resume,
    .driver     = {
        .name   = "at91_ohci",
        .owner  = THIS_MODULE,
        .of_match_table = of_match_ptr(at91_ohci_dt_ids),
    },
};