/*
* Exynos Specific Extensions for Synopsys DW Multimedia Card Interface driver
*
* Copyright (C) 2012, Samsung Electronics Co., Ltd.
*
* 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, or
* (at your option) any later version.
*/
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/clk.h>
#include <linux/mmc/host.h>
#include <linux/mmc/dw_mmc.h>
#include <linux/of.h>
#include <linux/of_gpio.h>
#include "dw_mmc.h"
#include "dw_mmc-pltfm.h"
#define NUM_PINS(x) (x + 2)
#define SDMMC_CLKSEL 0x09C
#define SDMMC_CLKSEL_CCLK_SAMPLE(x) (((x) & 7) << 0)
#define SDMMC_CLKSEL_CCLK_DRIVE(x) (((x) & 7) << 16)
#define SDMMC_CLKSEL_CCLK_DIVIDER(x) (((x) & 7) << 24)
#define SDMMC_CLKSEL_GET_DRV_WD3(x) (((x) >> 16) & 0x7)
#define SDMMC_CLKSEL_TIMING(x, y, z) (SDMMC_CLKSEL_CCLK_SAMPLE(x) | \
SDMMC_CLKSEL_CCLK_DRIVE(y) | \
SDMMC_CLKSEL_CCLK_DIVIDER(z))
#define SDMMC_CMD_USE_HOLD_REG BIT(29)
#define EXYNOS4210_FIXED_CIU_CLK_DIV 2
#define EXYNOS4412_FIXED_CIU_CLK_DIV 4
/* Variations in Exynos specific dw-mshc controller */
enum dw_mci_exynos_type {
DW_MCI_TYPE_EXYNOS4210,
DW_MCI_TYPE_EXYNOS4412,
DW_MCI_TYPE_EXYNOS5250,
};
/* Exynos implementation specific driver private data */
struct dw_mci_exynos_priv_data {
enum dw_mci_exynos_type ctrl_type;
u8 ciu_div;
u32 sdr_timing;
u32 ddr_timing;
};
static struct dw_mci_exynos_compatible {
char *compatible;
enum dw_mci_exynos_type ctrl_type;
} exynos_compat[] = {
{
.compatible = "samsung,exynos4210-dw-mshc",
.ctrl_type = DW_MCI_TYPE_EXYNOS4210,
}, {
.compatible = "samsung,exynos4412-dw-mshc",
.ctrl_type = DW_MCI_TYPE_EXYNOS4412,
}, {
.compatible = "samsung,exynos5250-dw-mshc",
.ctrl_type = DW_MCI_TYPE_EXYNOS5250,
},
};
static int dw_mci_exynos_priv_init(struct dw_mci *host)
{
struct dw_mci_exynos_priv_data *priv;
int idx;
priv = devm_kzalloc(host->dev, sizeof(*priv), GFP_KERNEL);
if (!priv) {
dev_err(host->dev, "mem alloc failed for private data\n");
return -ENOMEM;
}
for (idx = 0; idx < ARRAY_SIZE(exynos_compat); idx++) {
if (of_device_is_compatible(host->dev->of_node,
exynos_compat[idx].compatible))
priv->ctrl_type = exynos_compat[idx].ctrl_type;
}
host->priv = priv;
return 0;
}
static int dw_mci_exynos_setup_clock(struct dw_mci *host)
{
struct dw_mci_exynos_priv_data *priv = host->priv;
if (priv->ctrl_type == DW_MCI_TYPE_EXYNOS5250)
host->bus_hz /= (priv->ciu_div + 1);
else if (priv->ctrl_type == DW_MCI_TYPE_EXYNOS4412)
host->bus_hz /= EXYNOS4412_FIXED_CIU_CLK_DIV;
else if (priv->ctrl_type == DW_MCI_TYPE_EXYNOS4210)
host->bus_hz /= EXYNOS4210_FIXED_CIU_CLK_DIV;
return 0;
}
static void dw_mci_exynos_prepare_command(struct dw_mci *host, u32 *cmdr)
{
/*
* Exynos4412 and Exynos5250 extends the use of CMD register with the
* use of bit 29 (which is reserved on standard MSHC controllers) for
* optionally bypassing the HOLD register for command and data. The
* HOLD register should be bypassed in case there is no phase shift
* applied on CMD/DATA that is sent to the card.
*/
if (SDMMC_CLKSEL_GET_DRV_WD3(mci_readl(host, CLKSEL)))
*cmdr |= SDMMC_CMD_USE_HOLD_REG;
}
static void dw_mci_exynos_set_ios(struct dw_mci *host, struct mmc_ios *ios)
{
struct dw_mci_exynos_priv_data *priv = host->priv;
if (ios->timing == MMC_TIMING_UHS_DDR50)
mci_writel(host, CLKSEL, priv->ddr_timing);
else
mci_writel(host, CLKSEL, priv->sdr_timing);
}
static int dw_mci_exynos_parse_dt(struct dw_mci *host)
{
struct dw_mci_exynos_priv_data *priv = host->priv;
struct device_node *np = host->dev->of_node;
u32 timing[2];
u32 div = 0;
int ret;
of_property_read_u32(np, "samsung,dw-mshc-ciu-div", &div);
priv->ciu_div = div;
ret = of_property_read_u32_array(np,
"samsung,dw-mshc-sdr-timing", timing, 2);
if (ret)
return ret;
priv->sdr_timing = SDMMC_CLKSEL_TIMING(timing[0], timing[1], div);
ret = of_property_read_u32_array(np,
"samsung,dw-mshc-ddr-timing", timing, 2);
if (ret)
return ret;
priv->ddr_timing = SDMMC_CLKSEL_TIMING(timing[0], timing[1], div);
return 0;
}
static int dw_mci_exynos_setup_bus(struct dw_mci *host,
struct device_node *slot_np, u8 bus_width)
{
int idx, gpio, ret;
if (!slot_np)
return -EINVAL;
/* cmd + clock + bus-width pins */
for (idx = 0; idx < NUM_PINS(bus_width); idx++) {
gpio = of_get_gpio(slot_np, idx);
if (!gpio_is_valid(gpio)) {
dev_err(host->dev, "invalid gpio: %d\n", gpio);
return -EINVAL;
}
ret = devm_gpio_request(host->dev, gpio, "dw-mci-bus");
if (ret) {
dev_err(host->dev, "gpio [%d] request failed\n", gpio);
return -EBUSY;
}
}
gpio = of_get_named_gpio(slot_np, "wp-gpios", 0);
if (gpio_is_valid(gpio)) {
if (devm_gpio_request(host->dev, gpio, "dw-mci-wp"))
dev_info(host->dev, "gpio [%d] request failed\n",
gpio);
} else {
dev_info(host->dev, "wp gpio not available");
host->pdata->quirks |= DW_MCI_QUIRK_NO_WRITE_PROTECT;
}
if (host->pdata->quirks & DW_MCI_QUIRK_BROKEN_CARD_DETECTION)
return 0;
gpio = of_get_named_gpio(slot_np, "samsung,cd-pinmux-gpio", 0);
if (gpio_is_valid(gpio)) {
if (devm_gpio_request(host->dev, gpio, "dw-mci-cd"))
dev_err(host->dev, "gpio [%d] request failed\n", gpio);
} else {
dev_info(host->dev, "cd gpio not available");
}
return 0;
}
/* Exynos5250 controller specific capabilities */
static unsigned long exynos5250_dwmmc_caps[4] = {
MMC_CAP_UHS_DDR50 | MMC_CAP_1_8V_DDR |
MMC_CAP_8_BIT_DATA | MMC_CAP_CMD23,
MMC_CAP_CMD23,
MMC_CAP_CMD23,
MMC_CAP_CMD23,
};
static const struct dw_mci_drv_data exynos5250_drv_data = {
.caps = exynos5250_dwmmc_caps,
.init = dw_mci_exynos_priv_init,
.setup_clock = dw_mci_exynos_setup_clock,
.prepare_command = dw_mci_exynos_prepare_command,
.set_ios = dw_mci_exynos_set_ios,
.parse_dt = dw_mci_exynos_parse_dt,
.setup_bus = dw_mci_exynos_setup_bus,
};
static const struct of_device_id dw_mci_exynos_match[] = {
{ .compatible = "samsung,exynos5250-dw-mshc",
.data = &exynos5250_drv_data, },
{},
};
MODULE_DEVICE_TABLE(of, dw_mci_exynos_match);
int dw_mci_exynos_probe(struct platform_device *pdev)
{
const struct dw_mci_drv_data *drv_data;
const struct of_device_id *match;
match = of_match_node(dw_mci_exynos_match, pdev->dev.of_node);
drv_data = match->data;
return dw_mci_pltfm_register(pdev, drv_data);
}
static struct platform_driver dw_mci_exynos_pltfm_driver = {
.probe = dw_mci_exynos_probe,
.remove = __exit_p(dw_mci_pltfm_remove),
.driver = {
.name = "dwmmc_exynos",
.of_match_table = of_match_ptr(dw_mci_exynos_match),
.pm = &dw_mci_pltfm_pmops,
},
};
module_platform_driver(dw_mci_exynos_pltfm_driver);
MODULE_DESCRIPTION("Samsung Specific DW-MSHC Driver Extension");
MODULE_AUTHOR("Thomas Abraham <thomas.ab@samsung.com");
MODULE_LICENSE("GPL v2");
MODULE_ALIAS("platform:dwmmc-exynos");
