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[pohmelfs.git] / drivers / usb / dwc3 / core.c

/**
 * core.c - DesignWare USB3 DRD Controller Core file
 *
 * Copyright (C) 2010-2011 Texas Instruments Incorporated - http://www.ti.com
 *
 * Authors: Felipe Balbi <balbi@ti.com>,
 *          Sebastian Andrzej Siewior <bigeasy@linutronix.de>
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions, and the following disclaimer,
 *    without modification.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. The names of the above-listed copyright holders may not be used
 *    to endorse or promote products derived from this software without
 *    specific prior written permission.
 *
 * ALTERNATIVELY, this software may be distributed under the terms of the
 * GNU General Public License ("GPL") version 2, as published by the Free
 * Software Foundation.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
 * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
#include <linux/platform_device.h>
#include <linux/pm_runtime.h>
#include <linux/interrupt.h>
#include <linux/ioport.h>
#include <linux/io.h>
#include <linux/list.h>
#include <linux/delay.h>
#include <linux/dma-mapping.h>

#include <linux/usb/ch9.h>
#include <linux/usb/gadget.h>
#include <linux/module.h>

#include "core.h"
#include "gadget.h"
#include "io.h"

#include "debug.h"

static char *maximum_speed = "super";
module_param(maximum_speed, charp, 0);
MODULE_PARM_DESC(maximum_speed, "Maximum supported speed.");

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

#define DWC3_DEVS_POSSIBLE      32

static DECLARE_BITMAP(dwc3_devs, DWC3_DEVS_POSSIBLE);

int dwc3_get_device_id(void)
{
        int             id;

again:
        id = find_first_zero_bit(dwc3_devs, DWC3_DEVS_POSSIBLE);
        if (id < DWC3_DEVS_POSSIBLE) {
                int old;

                old = test_and_set_bit(id, dwc3_devs);
                if (old)
                        goto again;
        } else {
                pr_err("dwc3: no space for new device\n");
                id = -ENOMEM;
        }

        return 0;
}
EXPORT_SYMBOL_GPL(dwc3_get_device_id);

void dwc3_put_device_id(int id)
{
        int                     ret;

        if (id < 0)
                return;

        ret = test_bit(id, dwc3_devs);
        WARN(!ret, "dwc3: ID %d not in use\n", id);
        clear_bit(id, dwc3_devs);
}
EXPORT_SYMBOL_GPL(dwc3_put_device_id);

void dwc3_set_mode(struct dwc3 *dwc, u32 mode)
{
        u32 reg;

        reg = dwc3_readl(dwc->regs, DWC3_GCTL);
        reg &= ~(DWC3_GCTL_PRTCAPDIR(DWC3_GCTL_PRTCAP_OTG));
        reg |= DWC3_GCTL_PRTCAPDIR(mode);
        dwc3_writel(dwc->regs, DWC3_GCTL, reg);
}

/**
 * dwc3_core_soft_reset - Issues core soft reset and PHY reset
 * @dwc: pointer to our context structure
 */
static void dwc3_core_soft_reset(struct dwc3 *dwc)
{
        u32             reg;

        /* Before Resetting PHY, put Core in Reset */
        reg = dwc3_readl(dwc->regs, DWC3_GCTL);
        reg |= DWC3_GCTL_CORESOFTRESET;
        dwc3_writel(dwc->regs, DWC3_GCTL, reg);

        /* Assert USB3 PHY reset */
        reg = dwc3_readl(dwc->regs, DWC3_GUSB3PIPECTL(0));
        reg |= DWC3_GUSB3PIPECTL_PHYSOFTRST;
        dwc3_writel(dwc->regs, DWC3_GUSB3PIPECTL(0), reg);

        /* Assert USB2 PHY reset */
        reg = dwc3_readl(dwc->regs, DWC3_GUSB2PHYCFG(0));
        reg |= DWC3_GUSB2PHYCFG_PHYSOFTRST;
        dwc3_writel(dwc->regs, DWC3_GUSB2PHYCFG(0), reg);

        mdelay(100);

        /* Clear USB3 PHY reset */
        reg = dwc3_readl(dwc->regs, DWC3_GUSB3PIPECTL(0));
        reg &= ~DWC3_GUSB3PIPECTL_PHYSOFTRST;
        dwc3_writel(dwc->regs, DWC3_GUSB3PIPECTL(0), reg);

        /* Clear USB2 PHY reset */
        reg = dwc3_readl(dwc->regs, DWC3_GUSB2PHYCFG(0));
        reg &= ~DWC3_GUSB2PHYCFG_PHYSOFTRST;
        dwc3_writel(dwc->regs, DWC3_GUSB2PHYCFG(0), reg);

        /* After PHYs are stable we can take Core out of reset state */
        reg = dwc3_readl(dwc->regs, DWC3_GCTL);
        reg &= ~DWC3_GCTL_CORESOFTRESET;
        dwc3_writel(dwc->regs, DWC3_GCTL, reg);
}

/**
 * dwc3_free_one_event_buffer - Frees one event buffer
 * @dwc: Pointer to our controller context structure
 * @evt: Pointer to event buffer to be freed
 */
static void dwc3_free_one_event_buffer(struct dwc3 *dwc,
                struct dwc3_event_buffer *evt)
{
        dma_free_coherent(dwc->dev, evt->length, evt->buf, evt->dma);
        kfree(evt);
}

/**
 * dwc3_alloc_one_event_buffer - Allocated one event buffer structure
 * @dwc: Pointer to our controller context structure
 * @length: size of the event buffer
 *
 * Returns a pointer to the allocated event buffer structure on succes
 * otherwise ERR_PTR(errno).
 */
static struct dwc3_event_buffer *__devinit
dwc3_alloc_one_event_buffer(struct dwc3 *dwc, unsigned length)
{
        struct dwc3_event_buffer        *evt;

        evt = kzalloc(sizeof(*evt), GFP_KERNEL);
        if (!evt)
                return ERR_PTR(-ENOMEM);

        evt->dwc        = dwc;
        evt->length     = length;
        evt->buf        = dma_alloc_coherent(dwc->dev, length,
                        &evt->dma, GFP_KERNEL);
        if (!evt->buf) {
                kfree(evt);
                return ERR_PTR(-ENOMEM);
        }

        return evt;
}

/**
 * dwc3_free_event_buffers - frees all allocated event buffers
 * @dwc: Pointer to our controller context structure
 */
static void dwc3_free_event_buffers(struct dwc3 *dwc)
{
        struct dwc3_event_buffer        *evt;
        int i;

        for (i = 0; i < dwc->num_event_buffers; i++) {
                evt = dwc->ev_buffs[i];
                if (evt) {
                        dwc3_free_one_event_buffer(dwc, evt);
                        dwc->ev_buffs[i] = NULL;
                }
        }
}

/**
 * dwc3_alloc_event_buffers - Allocates @num event buffers of size @length
 * @dwc: Pointer to out controller context structure
 * @length: size of event buffer
 *
 * Returns 0 on success otherwise negative errno. In error the case, dwc
 * may contain some buffers allocated but not all which were requested.
 */
static int __devinit dwc3_alloc_event_buffers(struct dwc3 *dwc, unsigned length)
{
        int                     num;
        int                     i;

        num = DWC3_NUM_INT(dwc->hwparams.hwparams1);
        dwc->num_event_buffers = num;

        dwc->ev_buffs = kzalloc(sizeof(*dwc->ev_buffs) * num, GFP_KERNEL);
        if (!dwc->ev_buffs) {
                dev_err(dwc->dev, "can't allocate event buffers array\n");
                return -ENOMEM;
        }

        for (i = 0; i < num; i++) {
                struct dwc3_event_buffer        *evt;

                evt = dwc3_alloc_one_event_buffer(dwc, length);
                if (IS_ERR(evt)) {
                        dev_err(dwc->dev, "can't allocate event buffer\n");
                        return PTR_ERR(evt);
                }
                dwc->ev_buffs[i] = evt;
        }

        return 0;
}

/**
 * dwc3_event_buffers_setup - setup our allocated event buffers
 * @dwc: Pointer to out controller context structure
 *
 * Returns 0 on success otherwise negative errno.
 */
static int __devinit dwc3_event_buffers_setup(struct dwc3 *dwc)
{
        struct dwc3_event_buffer        *evt;
        int                             n;

        for (n = 0; n < dwc->num_event_buffers; n++) {
                evt = dwc->ev_buffs[n];
                dev_dbg(dwc->dev, "Event buf %p dma %08llx length %d\n",
                                evt->buf, (unsigned long long) evt->dma,
                                evt->length);

                dwc3_writel(dwc->regs, DWC3_GEVNTADRLO(n),
                                lower_32_bits(evt->dma));
                dwc3_writel(dwc->regs, DWC3_GEVNTADRHI(n),
                                upper_32_bits(evt->dma));
                dwc3_writel(dwc->regs, DWC3_GEVNTSIZ(n),
                                evt->length & 0xffff);
                dwc3_writel(dwc->regs, DWC3_GEVNTCOUNT(n), 0);
        }

        return 0;
}

static void dwc3_event_buffers_cleanup(struct dwc3 *dwc)
{
        struct dwc3_event_buffer        *evt;
        int                             n;

        for (n = 0; n < dwc->num_event_buffers; n++) {
                evt = dwc->ev_buffs[n];
                dwc3_writel(dwc->regs, DWC3_GEVNTADRLO(n), 0);
                dwc3_writel(dwc->regs, DWC3_GEVNTADRHI(n), 0);
                dwc3_writel(dwc->regs, DWC3_GEVNTSIZ(n), 0);
                dwc3_writel(dwc->regs, DWC3_GEVNTCOUNT(n), 0);
        }
}

static void __devinit dwc3_cache_hwparams(struct dwc3 *dwc)
{
        struct dwc3_hwparams    *parms = &dwc->hwparams;

        parms->hwparams0 = dwc3_readl(dwc->regs, DWC3_GHWPARAMS0);
        parms->hwparams1 = dwc3_readl(dwc->regs, DWC3_GHWPARAMS1);
        parms->hwparams2 = dwc3_readl(dwc->regs, DWC3_GHWPARAMS2);
        parms->hwparams3 = dwc3_readl(dwc->regs, DWC3_GHWPARAMS3);
        parms->hwparams4 = dwc3_readl(dwc->regs, DWC3_GHWPARAMS4);
        parms->hwparams5 = dwc3_readl(dwc->regs, DWC3_GHWPARAMS5);
        parms->hwparams6 = dwc3_readl(dwc->regs, DWC3_GHWPARAMS6);
        parms->hwparams7 = dwc3_readl(dwc->regs, DWC3_GHWPARAMS7);
        parms->hwparams8 = dwc3_readl(dwc->regs, DWC3_GHWPARAMS8);
}

/**
 * dwc3_core_init - Low-level initialization of DWC3 Core
 * @dwc: Pointer to our controller context structure
 *
 * Returns 0 on success otherwise negative errno.
 */
static int __devinit dwc3_core_init(struct dwc3 *dwc)
{
        unsigned long           timeout;
        u32                     reg;
        int                     ret;

        reg = dwc3_readl(dwc->regs, DWC3_GSNPSID);
        /* This should read as U3 followed by revision number */
        if ((reg & DWC3_GSNPSID_MASK) != 0x55330000) {
                dev_err(dwc->dev, "this is not a DesignWare USB3 DRD Core\n");
                ret = -ENODEV;
                goto err0;
        }
        dwc->revision = reg;

        dwc3_core_soft_reset(dwc);

        /* issue device SoftReset too */
        timeout = jiffies + msecs_to_jiffies(500);
        dwc3_writel(dwc->regs, DWC3_DCTL, DWC3_DCTL_CSFTRST);
        do {
                reg = dwc3_readl(dwc->regs, DWC3_DCTL);
                if (!(reg & DWC3_DCTL_CSFTRST))
                        break;

                if (time_after(jiffies, timeout)) {
                        dev_err(dwc->dev, "Reset Timed Out\n");
                        ret = -ETIMEDOUT;
                        goto err0;
                }

                cpu_relax();
        } while (true);

        dwc3_cache_hwparams(dwc);

        reg = dwc3_readl(dwc->regs, DWC3_GCTL);
        reg &= ~DWC3_GCTL_SCALEDOWN(3);
        reg &= ~DWC3_GCTL_DISSCRAMBLE;

        switch (DWC3_GHWPARAMS1_EN_PWROPT(dwc->hwparams.hwparams1)) {
        case DWC3_GHWPARAMS1_EN_PWROPT_CLK:
                reg &= ~DWC3_GCTL_DSBLCLKGTNG;
                break;
        default:
                dev_dbg(dwc->dev, "No power optimization available\n");
        }

        /*
         * WORKAROUND: DWC3 revisions <1.90a have a bug
         * when The device fails to connect at SuperSpeed
         * and falls back to high-speed mode which causes
         * the device to enter in a Connect/Disconnect loop
         */
        if (dwc->revision < DWC3_REVISION_190A)
                reg |= DWC3_GCTL_U2RSTECN;

        dwc3_writel(dwc->regs, DWC3_GCTL, reg);

        ret = dwc3_alloc_event_buffers(dwc, DWC3_EVENT_BUFFERS_SIZE);
        if (ret) {
                dev_err(dwc->dev, "failed to allocate event buffers\n");
                ret = -ENOMEM;
                goto err1;
        }

        ret = dwc3_event_buffers_setup(dwc);
        if (ret) {
                dev_err(dwc->dev, "failed to setup event buffers\n");
                goto err1;
        }

        return 0;

err1:
        dwc3_free_event_buffers(dwc);

err0:
        return ret;
}

static void dwc3_core_exit(struct dwc3 *dwc)
{
        dwc3_event_buffers_cleanup(dwc);
        dwc3_free_event_buffers(dwc);
}

#define DWC3_ALIGN_MASK         (16 - 1)

static int __devinit dwc3_probe(struct platform_device *pdev)
{
        struct resource         *res;
        struct dwc3             *dwc;

        int                     ret = -ENOMEM;
        int                     irq;

        void __iomem            *regs;
        void                    *mem;

        u8                      mode;

        mem = kzalloc(sizeof(*dwc) + DWC3_ALIGN_MASK, GFP_KERNEL);
        if (!mem) {
                dev_err(&pdev->dev, "not enough memory\n");
                goto err0;
        }
        dwc = PTR_ALIGN(mem, DWC3_ALIGN_MASK + 1);
        dwc->mem = mem;

        res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
        if (!res) {
                dev_err(&pdev->dev, "missing resource\n");
                goto err1;
        }

        dwc->res = res;

        res = request_mem_region(res->start, resource_size(res),
                        dev_name(&pdev->dev));
        if (!res) {
                dev_err(&pdev->dev, "can't request mem region\n");
                goto err1;
        }

        regs = ioremap(res->start, resource_size(res));
        if (!regs) {
                dev_err(&pdev->dev, "ioremap failed\n");
                goto err2;
        }

        irq = platform_get_irq(pdev, 0);
        if (irq < 0) {
                dev_err(&pdev->dev, "missing IRQ\n");
                goto err3;
        }

        spin_lock_init(&dwc->lock);
        platform_set_drvdata(pdev, dwc);

        dwc->regs       = regs;
        dwc->regs_size  = resource_size(res);
        dwc->dev        = &pdev->dev;
        dwc->irq        = irq;

        if (!strncmp("super", maximum_speed, 5))
                dwc->maximum_speed = DWC3_DCFG_SUPERSPEED;
        else if (!strncmp("high", maximum_speed, 4))
                dwc->maximum_speed = DWC3_DCFG_HIGHSPEED;
        else if (!strncmp("full", maximum_speed, 4))
                dwc->maximum_speed = DWC3_DCFG_FULLSPEED1;
        else if (!strncmp("low", maximum_speed, 3))
                dwc->maximum_speed = DWC3_DCFG_LOWSPEED;
        else
                dwc->maximum_speed = DWC3_DCFG_SUPERSPEED;

        pm_runtime_enable(&pdev->dev);
        pm_runtime_get_sync(&pdev->dev);
        pm_runtime_forbid(&pdev->dev);

        ret = dwc3_core_init(dwc);
        if (ret) {
                dev_err(&pdev->dev, "failed to initialize core\n");
                goto err3;
        }

        mode = DWC3_MODE(dwc->hwparams.hwparams0);

        switch (mode) {
        case DWC3_MODE_DEVICE:
                dwc3_set_mode(dwc, DWC3_GCTL_PRTCAP_DEVICE);
                ret = dwc3_gadget_init(dwc);
                if (ret) {
                        dev_err(&pdev->dev, "failed to initialize gadget\n");
                        goto err4;
                }
                break;
        case DWC3_MODE_HOST:
                dwc3_set_mode(dwc, DWC3_GCTL_PRTCAP_HOST);
                ret = dwc3_host_init(dwc);
                if (ret) {
                        dev_err(&pdev->dev, "failed to initialize host\n");
                        goto err4;
                }
                break;
        case DWC3_MODE_DRD:
                dwc3_set_mode(dwc, DWC3_GCTL_PRTCAP_OTG);
                ret = dwc3_host_init(dwc);
                if (ret) {
                        dev_err(&pdev->dev, "failed to initialize host\n");
                        goto err4;
                }

                ret = dwc3_gadget_init(dwc);
                if (ret) {
                        dev_err(&pdev->dev, "failed to initialize gadget\n");
                        goto err4;
                }
                break;
        default:
                dev_err(&pdev->dev, "Unsupported mode of operation %d\n", mode);
                goto err4;
        }
        dwc->mode = mode;

        ret = dwc3_debugfs_init(dwc);
        if (ret) {
                dev_err(&pdev->dev, "failed to initialize debugfs\n");
                goto err5;
        }

        pm_runtime_allow(&pdev->dev);

        return 0;

err5:
        switch (mode) {
        case DWC3_MODE_DEVICE:
                dwc3_gadget_exit(dwc);
                break;
        case DWC3_MODE_HOST:
                dwc3_host_exit(dwc);
                break;
        case DWC3_MODE_DRD:
                dwc3_host_exit(dwc);
                dwc3_gadget_exit(dwc);
                break;
        default:
                /* do nothing */
                break;
        }

err4:
        dwc3_core_exit(dwc);

err3:
        iounmap(regs);

err2:
        release_mem_region(res->start, resource_size(res));

err1:
        kfree(dwc->mem);

err0:
        return ret;
}

static int __devexit dwc3_remove(struct platform_device *pdev)
{
        struct dwc3     *dwc = platform_get_drvdata(pdev);
        struct resource *res;

        res = platform_get_resource(pdev, IORESOURCE_MEM, 0);

        pm_runtime_put(&pdev->dev);
        pm_runtime_disable(&pdev->dev);

        dwc3_debugfs_exit(dwc);

        switch (dwc->mode) {
        case DWC3_MODE_DEVICE:
                dwc3_gadget_exit(dwc);
                break;
        case DWC3_MODE_HOST:
                dwc3_host_exit(dwc);
                break;
        case DWC3_MODE_DRD:
                dwc3_host_exit(dwc);
                dwc3_gadget_exit(dwc);
                break;
        default:
                /* do nothing */
                break;
        }

        dwc3_core_exit(dwc);
        release_mem_region(res->start, resource_size(res));
        iounmap(dwc->regs);
        kfree(dwc->mem);

        return 0;
}

static struct platform_driver dwc3_driver = {
        .probe          = dwc3_probe,
        .remove         = __devexit_p(dwc3_remove),
        .driver         = {
                .name   = "dwc3",
        },
};

MODULE_ALIAS("platform:dwc3");
MODULE_AUTHOR("Felipe Balbi <balbi@ti.com>");
MODULE_LICENSE("Dual BSD/GPL");
MODULE_DESCRIPTION("DesignWare USB3 DRD Controller Driver");

static int __devinit dwc3_init(void)
{
        return platform_driver_register(&dwc3_driver);
}
module_init(dwc3_init);

static void __exit dwc3_exit(void)
{
        platform_driver_unregister(&dwc3_driver);
}
module_exit(dwc3_exit);