diff options
Diffstat (limited to 'drivers/mmc/host/dw_mmc-exynos.c')
| -rw-r--r-- | drivers/mmc/host/dw_mmc-exynos.c | 253 |
1 files changed, 253 insertions, 0 deletions
diff --git a/drivers/mmc/host/dw_mmc-exynos.c b/drivers/mmc/host/dw_mmc-exynos.c new file mode 100644 index 000000000000..660bbc528862 --- /dev/null +++ b/drivers/mmc/host/dw_mmc-exynos.c @@ -0,0 +1,253 @@ +/* + * 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 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 = (void *)&exynos5250_drv_data, }, + {}, +}; +MODULE_DEVICE_TABLE(of, dw_mci_pltfm_match); + +int dw_mci_exynos_probe(struct platform_device *pdev) +{ + 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"); |