pxa3xx-ulpi.c

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/*
 * linux/arch/arm/mach-pxa/pxa3xx-ulpi.c
 *
 * code specific to pxa3xx aka Monahans
 *
 * Copyright (C) 2010 CompuLab Ltd.
 *
 * 2010-13-07: Igor Grinberg <[email protected]>
 *             initial version: pxa310 USB Host mode support
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 */

#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/device.h>
#include <linux/platform_device.h>
#include <linux/err.h>
#include <linux/io.h>
#include <linux/delay.h>
#include <linux/clk.h>
#include <linux/usb.h>
#include <linux/usb/otg.h>

#include <mach/hardware.h>
#include <mach/regs-u2d.h>
#include <linux/platform_data/usb-pxa3xx-ulpi.h>

struct pxa3xx_u2d_ulpi {
    struct clk      *clk;
    void __iomem        *mmio_base;

    struct usb_phy      *otg;
    unsigned int        ulpi_mode;
};

static struct pxa3xx_u2d_ulpi *u2d;

static inline u32 u2d_readl(u32 reg)
{
    return __raw_readl(u2d->mmio_base + reg);
}

static inline void u2d_writel(u32 reg, u32 val)
{
    __raw_writel(val, u2d->mmio_base + reg);
}

#if defined(CONFIG_PXA310_ULPI)
enum u2d_ulpi_phy_mode {
    SYNCH       = 0,
    CARKIT      = (1 << 0),
    SER_3PIN    = (1 << 1),
    SER_6PIN    = (1 << 2),
    LOWPOWER    = (1 << 3),
};

static inline enum u2d_ulpi_phy_mode pxa310_ulpi_get_phymode(void)
{
    return (u2d_readl(U2DOTGUSR) >> 28) & 0xF;
}

static int pxa310_ulpi_poll(void)
{
    int timeout = 50000;

    while (timeout--) {
        if (!(u2d_readl(U2DOTGUCR) & U2DOTGUCR_RUN))
            return 0;

        cpu_relax();
    }

    pr_warning("%s: ULPI access timed out!\n", __func__);

    return -ETIMEDOUT;
}

static int pxa310_ulpi_read(struct usb_phy *otg, u32 reg)
{
    int err;

    if (pxa310_ulpi_get_phymode() != SYNCH) {
        pr_warning("%s: PHY is not in SYNCH mode!\n", __func__);
        return -EBUSY;
    }

    u2d_writel(U2DOTGUCR, U2DOTGUCR_RUN | U2DOTGUCR_RNW | (reg << 16));
    msleep(5);

    err = pxa310_ulpi_poll();
    if (err)
        return err;

    return u2d_readl(U2DOTGUCR) & U2DOTGUCR_RDATA;
}

static int pxa310_ulpi_write(struct usb_phy *otg, u32 val, u32 reg)
{
    if (pxa310_ulpi_get_phymode() != SYNCH) {
        pr_warning("%s: PHY is not in SYNCH mode!\n", __func__);
        return -EBUSY;
    }

    u2d_writel(U2DOTGUCR, U2DOTGUCR_RUN | (reg << 16) | (val << 8));
    msleep(5);

    return pxa310_ulpi_poll();
}

struct usb_phy_io_ops pxa310_ulpi_access_ops = {
    .read   = pxa310_ulpi_read,
    .write  = pxa310_ulpi_write,
};

static void pxa310_otg_transceiver_rtsm(void)
{
    u32 u2dotgcr;

    /* put PHY to sync mode */
    u2dotgcr = u2d_readl(U2DOTGCR);
    u2dotgcr |=  U2DOTGCR_RTSM | U2DOTGCR_UTMID;
    u2d_writel(U2DOTGCR, u2dotgcr);
    msleep(10);

    /* setup OTG sync mode */
    u2dotgcr = u2d_readl(U2DOTGCR);
    u2dotgcr |= U2DOTGCR_ULAF;
    u2dotgcr &= ~(U2DOTGCR_SMAF | U2DOTGCR_CKAF);
    u2d_writel(U2DOTGCR, u2dotgcr);
}

static int pxa310_start_otg_host_transcvr(struct usb_bus *host)
{
    int err;

    pxa310_otg_transceiver_rtsm();

    err = usb_phy_init(u2d->otg);
    if (err) {
        pr_err("OTG transceiver init failed");
        return err;
    }

    err = otg_set_vbus(u2d->otg->otg, 1);
    if (err) {
        pr_err("OTG transceiver VBUS set failed");
        return err;
    }

    err = otg_set_host(u2d->otg->otg, host);
    if (err)
        pr_err("OTG transceiver Host mode set failed");

    return err;
}

static int pxa310_start_otg_hc(struct usb_bus *host)
{
    u32 u2dotgcr;
    int err;

    /* disable USB device controller */
    u2d_writel(U2DCR, u2d_readl(U2DCR) & ~U2DCR_UDE);
    u2d_writel(U2DOTGCR, u2d_readl(U2DOTGCR) | U2DOTGCR_UTMID);
    u2d_writel(U2DOTGICR, u2d_readl(U2DOTGICR) & ~0x37F7F);

    err = pxa310_start_otg_host_transcvr(host);
    if (err)
        return err;

    /* set xceiver mode */
    if (u2d->ulpi_mode & ULPI_IC_6PIN_SERIAL)
        u2d_writel(U2DP3CR, u2d_readl(U2DP3CR) & ~U2DP3CR_P2SS);
    else if (u2d->ulpi_mode & ULPI_IC_3PIN_SERIAL)
        u2d_writel(U2DP3CR, u2d_readl(U2DP3CR) | U2DP3CR_P2SS);

    /* start OTG host controller */
    u2dotgcr = u2d_readl(U2DOTGCR) | U2DOTGCR_SMAF;
    u2d_writel(U2DOTGCR, u2dotgcr & ~(U2DOTGCR_ULAF | U2DOTGCR_CKAF));

    return 0;
}

static void pxa310_stop_otg_hc(void)
{
    pxa310_otg_transceiver_rtsm();

    otg_set_host(u2d->otg->otg, NULL);
    otg_set_vbus(u2d->otg->otg, 0);
    usb_phy_shutdown(u2d->otg);
}

static void pxa310_u2d_setup_otg_hc(void)
{
    u32 u2dotgcr;

    u2dotgcr = u2d_readl(U2DOTGCR);
    u2dotgcr |= U2DOTGCR_ULAF | U2DOTGCR_UTMID;
    u2dotgcr &= ~(U2DOTGCR_SMAF | U2DOTGCR_CKAF);
    u2d_writel(U2DOTGCR, u2dotgcr);
    msleep(5);
    u2d_writel(U2DOTGCR, u2dotgcr | U2DOTGCR_ULE);
    msleep(5);
    u2d_writel(U2DOTGICR, u2d_readl(U2DOTGICR) & ~0x37F7F);
}

static int pxa310_otg_init(struct pxa3xx_u2d_platform_data *pdata)
{
    unsigned int ulpi_mode = ULPI_OTG_DRVVBUS;

    if (pdata) {
        if (pdata->ulpi_mode & ULPI_SER_6PIN)
            ulpi_mode |= ULPI_IC_6PIN_SERIAL;
        else if (pdata->ulpi_mode & ULPI_SER_3PIN)
            ulpi_mode |= ULPI_IC_3PIN_SERIAL;
    }

    u2d->ulpi_mode = ulpi_mode;

    u2d->otg = otg_ulpi_create(&pxa310_ulpi_access_ops, ulpi_mode);
    if (!u2d->otg)
        return -ENOMEM;

    u2d->otg->io_priv = u2d->mmio_base;

    return 0;
}

static void pxa310_otg_exit(void)
{
    kfree(u2d->otg);
}
#else
static inline void pxa310_u2d_setup_otg_hc(void) {}
static inline int pxa310_start_otg_hc(struct usb_bus *host)
{
    return 0;
}
static inline void pxa310_stop_otg_hc(void) {}
static inline int pxa310_otg_init(struct pxa3xx_u2d_platform_data *pdata)
{
    return 0;
}
static inline void pxa310_otg_exit(void) {}
#endif /* CONFIG_PXA310_ULPI */

int pxa3xx_u2d_start_hc(struct usb_bus *host)
{
    int err = 0;

    /* In case the PXA3xx ULPI isn't used, do nothing. */
    if (!u2d)
        return 0;

    clk_enable(u2d->clk);

    if (cpu_is_pxa310()) {
        pxa310_u2d_setup_otg_hc();
        err = pxa310_start_otg_hc(host);
    }

    return err;
}
EXPORT_SYMBOL_GPL(pxa3xx_u2d_start_hc);

void pxa3xx_u2d_stop_hc(struct usb_bus *host)
{
    /* In case the PXA3xx ULPI isn't used, do nothing. */
    if (!u2d)
        return;

    if (cpu_is_pxa310())
        pxa310_stop_otg_hc();

    clk_disable(u2d->clk);
}
EXPORT_SYMBOL_GPL(pxa3xx_u2d_stop_hc);

static int pxa3xx_u2d_probe(struct platform_device *pdev)
{
    struct pxa3xx_u2d_platform_data *pdata = pdev->dev.platform_data;
    struct resource *r;
    int err;

    u2d = kzalloc(sizeof(struct pxa3xx_u2d_ulpi), GFP_KERNEL);
    if (!u2d) {
        dev_err(&pdev->dev, "failed to allocate memory\n");
        return -ENOMEM;
    }

    u2d->clk = clk_get(&pdev->dev, NULL);
    if (IS_ERR(u2d->clk)) {
        dev_err(&pdev->dev, "failed to get u2d clock\n");
        err = PTR_ERR(u2d->clk);
        goto err_free_mem;
    }

    r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
    if (!r) {
        dev_err(&pdev->dev, "no IO memory resource defined\n");
        err = -ENODEV;
        goto err_put_clk;
    }

        r = request_mem_region(r->start, resource_size(r), pdev->name);
        if (!r) {
                dev_err(&pdev->dev, "failed to request memory resource\n");
                err = -EBUSY;
                goto err_put_clk;
        }

    u2d->mmio_base = ioremap(r->start, resource_size(r));
    if (!u2d->mmio_base) {
        dev_err(&pdev->dev, "ioremap() failed\n");
        err = -ENODEV;
        goto err_free_res;
    }

    if (pdata->init) {
        err = pdata->init(&pdev->dev);
        if (err)
            goto err_free_io;
    }

    /* Only PXA310 U2D has OTG functionality */
    if (cpu_is_pxa310()) {
        err = pxa310_otg_init(pdata);
        if (err)
            goto err_free_plat;
    }

    platform_set_drvdata(pdev, &u2d);

    return 0;

err_free_plat:
    if (pdata->exit)
        pdata->exit(&pdev->dev);
err_free_io:
    iounmap(u2d->mmio_base);
err_free_res:
    release_mem_region(r->start, resource_size(r));
err_put_clk:
    clk_put(u2d->clk);
err_free_mem:
    kfree(u2d);
    return err;
}

static int pxa3xx_u2d_remove(struct platform_device *pdev)
{
    struct pxa3xx_u2d_platform_data *pdata = pdev->dev.platform_data;
    struct resource *r;

    if (cpu_is_pxa310()) {
        pxa310_stop_otg_hc();
        pxa310_otg_exit();
    }

    if (pdata->exit)
        pdata->exit(&pdev->dev);

    platform_set_drvdata(pdev, NULL);
    iounmap(u2d->mmio_base);
    r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
    release_mem_region(r->start, resource_size(r));

    clk_put(u2d->clk);

    kfree(u2d);

    return 0;
}

static struct platform_driver pxa3xx_u2d_ulpi_driver = {
        .driver     = {
                .name   = "pxa3xx-u2d",
        .owner  = THIS_MODULE,
        },
        .probe          = pxa3xx_u2d_probe,
        .remove         = pxa3xx_u2d_remove,
};

static int pxa3xx_u2d_ulpi_init(void)
{
    return platform_driver_register(&pxa3xx_u2d_ulpi_driver);
}
module_init(pxa3xx_u2d_ulpi_init);

static void __exit pxa3xx_u2d_ulpi_exit(void)
{
    platform_driver_unregister(&pxa3xx_u2d_ulpi_driver);
}
module_exit(pxa3xx_u2d_ulpi_exit);

MODULE_DESCRIPTION("PXA3xx U2D ULPI driver");
MODULE_AUTHOR("Igor Grinberg");
MODULE_LICENSE("GPL v2");