mcp-sa11x0.c

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/*
 *  linux/drivers/mfd/mcp-sa11x0.c
 *
 *  Copyright (C) 2001-2005 Russell King
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License.
 *
 *  SA11x0 MCP (Multimedia Communications Port) driver.
 *
 *  MCP read/write timeouts from Jordi Colomer, rehacked by rmk.
 */
#include <linux/module.h>
#include <linux/init.h>
#include <linux/io.h>
#include <linux/errno.h>
#include <linux/kernel.h>
#include <linux/delay.h>
#include <linux/spinlock.h>
#include <linux/platform_device.h>
#include <linux/pm.h>
#include <linux/mfd/mcp.h>

#include <mach/hardware.h>
#include <asm/mach-types.h>
#include <linux/platform_data/mfd-mcp-sa11x0.h>

#define DRIVER_NAME "sa11x0-mcp"

struct mcp_sa11x0 {
    void __iomem    *base0;
    void __iomem    *base1;
    u32     mccr0;
    u32     mccr1;
};

/* Register offsets */
#define MCCR0(m)    ((m)->base0 + 0x00)
#define MCDR0(m)    ((m)->base0 + 0x08)
#define MCDR1(m)    ((m)->base0 + 0x0c)
#define MCDR2(m)    ((m)->base0 + 0x10)
#define MCSR(m)     ((m)->base0 + 0x18)
#define MCCR1(m)    ((m)->base1 + 0x00)

#define priv(mcp)   ((struct mcp_sa11x0 *)mcp_priv(mcp))

static void
mcp_sa11x0_set_telecom_divisor(struct mcp *mcp, unsigned int divisor)
{
    struct mcp_sa11x0 *m = priv(mcp);

    divisor /= 32;

    m->mccr0 &= ~0x00007f00;
    m->mccr0 |= divisor << 8;
    writel_relaxed(m->mccr0, MCCR0(m));
}

static void
mcp_sa11x0_set_audio_divisor(struct mcp *mcp, unsigned int divisor)
{
    struct mcp_sa11x0 *m = priv(mcp);

    divisor /= 32;

    m->mccr0 &= ~0x0000007f;
    m->mccr0 |= divisor;
    writel_relaxed(m->mccr0, MCCR0(m));
}

/*
 * Write data to the device.  The bit should be set after 3 subframe
 * times (each frame is 64 clocks).  We wait a maximum of 6 subframes.
 * We really should try doing something more productive while we
 * wait.
 */
static void
mcp_sa11x0_write(struct mcp *mcp, unsigned int reg, unsigned int val)
{
    struct mcp_sa11x0 *m = priv(mcp);
    int ret = -ETIME;
    int i;

    writel_relaxed(reg << 17 | MCDR2_Wr | (val & 0xffff), MCDR2(m));

    for (i = 0; i < 2; i++) {
        udelay(mcp->rw_timeout);
        if (readl_relaxed(MCSR(m)) & MCSR_CWC) {
            ret = 0;
            break;
        }
    }

    if (ret < 0)
        printk(KERN_WARNING "mcp: write timed out\n");
}

/*
 * Read data from the device.  The bit should be set after 3 subframe
 * times (each frame is 64 clocks).  We wait a maximum of 6 subframes.
 * We really should try doing something more productive while we
 * wait.
 */
static unsigned int
mcp_sa11x0_read(struct mcp *mcp, unsigned int reg)
{
    struct mcp_sa11x0 *m = priv(mcp);
    int ret = -ETIME;
    int i;

    writel_relaxed(reg << 17 | MCDR2_Rd, MCDR2(m));

    for (i = 0; i < 2; i++) {
        udelay(mcp->rw_timeout);
        if (readl_relaxed(MCSR(m)) & MCSR_CRC) {
            ret = readl_relaxed(MCDR2(m)) & 0xffff;
            break;
        }
    }

    if (ret < 0)
        printk(KERN_WARNING "mcp: read timed out\n");

    return ret;
}

static void mcp_sa11x0_enable(struct mcp *mcp)
{
    struct mcp_sa11x0 *m = priv(mcp);

    writel(-1, MCSR(m));
    m->mccr0 |= MCCR0_MCE;
    writel_relaxed(m->mccr0, MCCR0(m));
}

static void mcp_sa11x0_disable(struct mcp *mcp)
{
    struct mcp_sa11x0 *m = priv(mcp);

    m->mccr0 &= ~MCCR0_MCE;
    writel_relaxed(m->mccr0, MCCR0(m));
}

/*
 * Our methods.
 */
static struct mcp_ops mcp_sa11x0 = {
    .set_telecom_divisor    = mcp_sa11x0_set_telecom_divisor,
    .set_audio_divisor  = mcp_sa11x0_set_audio_divisor,
    .reg_write      = mcp_sa11x0_write,
    .reg_read       = mcp_sa11x0_read,
    .enable         = mcp_sa11x0_enable,
    .disable        = mcp_sa11x0_disable,
};

static int mcp_sa11x0_probe(struct platform_device *dev)
{
    struct mcp_plat_data *data = dev->dev.platform_data;
    struct resource *mem0, *mem1;
    struct mcp_sa11x0 *m;
    struct mcp *mcp;
    int ret;

    if (!data)
        return -ENODEV;

    mem0 = platform_get_resource(dev, IORESOURCE_MEM, 0);
    mem1 = platform_get_resource(dev, IORESOURCE_MEM, 1);
    if (!mem0 || !mem1)
        return -ENXIO;

    if (!request_mem_region(mem0->start, resource_size(mem0),
                DRIVER_NAME)) {
        ret = -EBUSY;
        goto err_mem0;
    }

    if (!request_mem_region(mem1->start, resource_size(mem1),
                DRIVER_NAME)) {
        ret = -EBUSY;
        goto err_mem1;
    }

    mcp = mcp_host_alloc(&dev->dev, sizeof(struct mcp_sa11x0));
    if (!mcp) {
        ret = -ENOMEM;
        goto err_alloc;
    }

    mcp->owner      = THIS_MODULE;
    mcp->ops        = &mcp_sa11x0;
    mcp->sclk_rate      = data->sclk_rate;

    m = priv(mcp);
    m->mccr0 = data->mccr0 | 0x7f7f;
    m->mccr1 = data->mccr1;

    m->base0 = ioremap(mem0->start, resource_size(mem0));
    m->base1 = ioremap(mem1->start, resource_size(mem1));
    if (!m->base0 || !m->base1) {
        ret = -ENOMEM;
        goto err_ioremap;
    }

    platform_set_drvdata(dev, mcp);

    /*
     * Initialise device.  Note that we initially
     * set the sampling rate to minimum.
     */
    writel_relaxed(-1, MCSR(m));
    writel_relaxed(m->mccr1, MCCR1(m));
    writel_relaxed(m->mccr0, MCCR0(m));

    /*
     * Calculate the read/write timeout (us) from the bit clock
     * rate.  This is the period for 3 64-bit frames.  Always
     * round this time up.
     */
    mcp->rw_timeout = (64 * 3 * 1000000 + mcp->sclk_rate - 1) /
              mcp->sclk_rate;

    ret = mcp_host_add(mcp, data->codec_pdata);
    if (ret == 0)
        return 0;

    platform_set_drvdata(dev, NULL);

 err_ioremap:
    iounmap(m->base1);
    iounmap(m->base0);
    mcp_host_free(mcp);
 err_alloc:
    release_mem_region(mem1->start, resource_size(mem1));
 err_mem1:
    release_mem_region(mem0->start, resource_size(mem0));
 err_mem0:
    return ret;
}

static int mcp_sa11x0_remove(struct platform_device *dev)
{
    struct mcp *mcp = platform_get_drvdata(dev);
    struct mcp_sa11x0 *m = priv(mcp);
    struct resource *mem0, *mem1;

    if (m->mccr0 & MCCR0_MCE)
        dev_warn(&dev->dev,
             "device left active (missing disable call?)\n");

    mem0 = platform_get_resource(dev, IORESOURCE_MEM, 0);
    mem1 = platform_get_resource(dev, IORESOURCE_MEM, 1);

    platform_set_drvdata(dev, NULL);
    mcp_host_del(mcp);
    iounmap(m->base1);
    iounmap(m->base0);
    mcp_host_free(mcp);
    release_mem_region(mem1->start, resource_size(mem1));
    release_mem_region(mem0->start, resource_size(mem0));

    return 0;
}

#ifdef CONFIG_PM_SLEEP
static int mcp_sa11x0_suspend(struct device *dev)
{
    struct mcp_sa11x0 *m = priv(dev_get_drvdata(dev));

    if (m->mccr0 & MCCR0_MCE)
        dev_warn(dev, "device left active (missing disable call?)\n");

    writel(m->mccr0 & ~MCCR0_MCE, MCCR0(m));

    return 0;
}

static int mcp_sa11x0_resume(struct device *dev)
{
    struct mcp_sa11x0 *m = priv(dev_get_drvdata(dev));

    writel_relaxed(m->mccr1, MCCR1(m));
    writel_relaxed(m->mccr0, MCCR0(m));

    return 0;
}
#endif

static const struct dev_pm_ops mcp_sa11x0_pm_ops = {
#ifdef CONFIG_PM_SLEEP
    .suspend = mcp_sa11x0_suspend,
    .freeze = mcp_sa11x0_suspend,
    .poweroff = mcp_sa11x0_suspend,
    .resume_noirq = mcp_sa11x0_resume,
    .thaw_noirq = mcp_sa11x0_resume,
    .restore_noirq = mcp_sa11x0_resume,
#endif
};

static struct platform_driver mcp_sa11x0_driver = {
    .probe      = mcp_sa11x0_probe,
    .remove     = mcp_sa11x0_remove,
    .driver     = {
        .name   = DRIVER_NAME,
        .owner  = THIS_MODULE,
        .pm = &mcp_sa11x0_pm_ops,
    },
};

/*
 * This needs re-working
 */
module_platform_driver(mcp_sa11x0_driver);

MODULE_ALIAS("platform:" DRIVER_NAME);
MODULE_AUTHOR("Russell King <[email protected]>");
MODULE_DESCRIPTION("SA11x0 multimedia communications port driver");
MODULE_LICENSE("GPL");