msdi.c

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/*
 * MSDI IP block reset
 *
 * Copyright (C) 2012 Texas Instruments, Inc.
 * Paul Walmsley
 *
 * 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.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
 * 02110-1301 USA
 *
 * XXX What about pad muxing?
 */

#include <linux/kernel.h>
#include <linux/err.h>
#include <linux/platform_data/gpio-omap.h>

#include <plat/omap_hwmod.h>
#include <plat/omap_device.h>
#include <plat/mmc.h>

#include "common.h"
#include "control.h"
#include "mux.h"

/*
 * MSDI_CON_OFFSET: offset in bytes of the MSDI IP block's CON register
 *     from the IP block's base address
 */
#define MSDI_CON_OFFSET             0x0c

/* Register bitfields in the CON register */
#define MSDI_CON_POW_MASK           BIT(11)
#define MSDI_CON_CLKD_MASK          (0x3f << 0)
#define MSDI_CON_CLKD_SHIFT         0

/* Maximum microseconds to wait for OMAP module to softreset */
#define MAX_MODULE_SOFTRESET_WAIT   10000

/* MSDI_TARGET_RESET_CLKD: clock divisor to use throughout the reset */
#define MSDI_TARGET_RESET_CLKD      0x3ff

int omap_msdi_reset(struct omap_hwmod *oh)
{
    u16 v = 0;
    int c = 0;

    /* Write to the SOFTRESET bit */
    omap_hwmod_softreset(oh);

    /* Enable the MSDI core and internal clock */
    v |= MSDI_CON_POW_MASK;
    v |= MSDI_TARGET_RESET_CLKD << MSDI_CON_CLKD_SHIFT;
    omap_hwmod_write(v, oh, MSDI_CON_OFFSET);

    /* Poll on RESETDONE bit */
    omap_test_timeout((omap_hwmod_read(oh, oh->class->sysc->syss_offs)
               & SYSS_RESETDONE_MASK),
              MAX_MODULE_SOFTRESET_WAIT, c);

    if (c == MAX_MODULE_SOFTRESET_WAIT)
        pr_warning("%s: %s: softreset failed (waited %d usec)\n",
               __func__, oh->name, MAX_MODULE_SOFTRESET_WAIT);
    else
        pr_debug("%s: %s: softreset in %d usec\n", __func__,
             oh->name, c);

    /* Disable the MSDI internal clock */
    v &= ~MSDI_CON_CLKD_MASK;
    omap_hwmod_write(v, oh, MSDI_CON_OFFSET);

    return 0;
}

#if defined(CONFIG_MMC_OMAP) || defined(CONFIG_MMC_OMAP_MODULE)

static inline void omap242x_mmc_mux(struct omap_mmc_platform_data
                    *mmc_controller)
{
    if ((mmc_controller->slots[0].switch_pin > 0) && \
        (mmc_controller->slots[0].switch_pin < OMAP_MAX_GPIO_LINES))
        omap_mux_init_gpio(mmc_controller->slots[0].switch_pin,
                    OMAP_PIN_INPUT_PULLUP);
    if ((mmc_controller->slots[0].gpio_wp > 0) && \
        (mmc_controller->slots[0].gpio_wp < OMAP_MAX_GPIO_LINES))
        omap_mux_init_gpio(mmc_controller->slots[0].gpio_wp,
                    OMAP_PIN_INPUT_PULLUP);

    omap_mux_init_signal("sdmmc_cmd", 0);
    omap_mux_init_signal("sdmmc_clki", 0);
    omap_mux_init_signal("sdmmc_clko", 0);
    omap_mux_init_signal("sdmmc_dat0", 0);
    omap_mux_init_signal("sdmmc_dat_dir0", 0);
    omap_mux_init_signal("sdmmc_cmd_dir", 0);
    if (mmc_controller->slots[0].caps & MMC_CAP_4_BIT_DATA) {
        omap_mux_init_signal("sdmmc_dat1", 0);
        omap_mux_init_signal("sdmmc_dat2", 0);
        omap_mux_init_signal("sdmmc_dat3", 0);
        omap_mux_init_signal("sdmmc_dat_dir1", 0);
        omap_mux_init_signal("sdmmc_dat_dir2", 0);
        omap_mux_init_signal("sdmmc_dat_dir3", 0);
    }

    /*
     * Use internal loop-back in MMC/SDIO Module Input Clock
     * selection
     */
    if (mmc_controller->slots[0].internal_clock) {
        u32 v = omap_ctrl_readl(OMAP2_CONTROL_DEVCONF0);
        v |= (1 << 24);
        omap_ctrl_writel(v, OMAP2_CONTROL_DEVCONF0);
    }
}

void __init omap242x_init_mmc(struct omap_mmc_platform_data **mmc_data)
{
    struct platform_device *pdev;
    struct omap_hwmod *oh;
    int id = 0;
    char *oh_name = "msdi1";
    char *dev_name = "mmci-omap";

    if (!mmc_data[0]) {
        pr_err("%s fails: Incomplete platform data\n", __func__);
        return;
    }

    omap242x_mmc_mux(mmc_data[0]);

    oh = omap_hwmod_lookup(oh_name);
    if (!oh) {
        pr_err("Could not look up %s\n", oh_name);
        return;
    }
    pdev = omap_device_build(dev_name, id, oh, mmc_data[0],
                 sizeof(struct omap_mmc_platform_data), NULL, 0, 0);
    if (IS_ERR(pdev))
        WARN(1, "Can'd build omap_device for %s:%s.\n",
                    dev_name, oh->name);
}

#endif