/*
* 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 <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
/**
* omap_msdi_reset - reset the MSDI IP block
* @oh: struct omap_hwmod *
*
* The MSDI IP block on OMAP2420 has to have both the POW and CLKD
* fields set inside its CON register for a reset to complete
* successfully. This is not documented in the TRM. For CLKD, we use
* the value that results in the lowest possible clock rate, to attempt
* to avoid disturbing any cards.
*/
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
