diff options
Diffstat (limited to 'drivers/mmc/host/of_mmc_spi.c')
| -rw-r--r-- | drivers/mmc/host/of_mmc_spi.c | 149 |
1 files changed, 149 insertions, 0 deletions
diff --git a/drivers/mmc/host/of_mmc_spi.c b/drivers/mmc/host/of_mmc_spi.c new file mode 100644 index 0000000..fb2921f --- /dev/null +++ b/drivers/mmc/host/of_mmc_spi.c @@ -0,0 +1,149 @@ +/* + * OpenFirmware bindings for the MMC-over-SPI driver + * + * Copyright (c) MontaVista Software, Inc. 2008. + * + * Author: Anton Vorontsov <avorontsov@ru.mvista.com> + * + * 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/kernel.h> +#include <linux/module.h> +#include <linux/device.h> +#include <linux/gpio.h> +#include <linux/of.h> +#include <linux/of_gpio.h> +#include <linux/spi/spi.h> +#include <linux/spi/mmc_spi.h> +#include <linux/mmc/core.h> +#include <linux/mmc/host.h> + +enum { + CD_GPIO = 0, + WP_GPIO, + NUM_GPIOS, +}; + +struct of_mmc_spi { + int gpios[NUM_GPIOS]; + bool alow_gpios[NUM_GPIOS]; + struct mmc_spi_platform_data pdata; +}; + +static struct of_mmc_spi *to_of_mmc_spi(struct device *dev) +{ + return container_of(dev->platform_data, struct of_mmc_spi, pdata); +} + +static int of_mmc_spi_read_gpio(struct device *dev, int gpio_num) +{ + struct of_mmc_spi *oms = to_of_mmc_spi(dev); + bool active_low = oms->alow_gpios[gpio_num]; + bool value = gpio_get_value(oms->gpios[gpio_num]); + + return active_low ^ value; +} + +static int of_mmc_spi_get_cd(struct device *dev) +{ + return of_mmc_spi_read_gpio(dev, CD_GPIO); +} + +static int of_mmc_spi_get_ro(struct device *dev) +{ + return of_mmc_spi_read_gpio(dev, WP_GPIO); +} + +struct mmc_spi_platform_data *mmc_spi_get_pdata(struct spi_device *spi) +{ + struct device *dev = &spi->dev; + struct device_node *np = dev_archdata_get_node(&dev->archdata); + struct of_mmc_spi *oms; + const u32 *voltage_ranges; + int num_ranges; + int i; + int ret = -EINVAL; + + if (dev->platform_data || !np) + return dev->platform_data; + + oms = kzalloc(sizeof(*oms), GFP_KERNEL); + if (!oms) + return NULL; + + voltage_ranges = of_get_property(np, "voltage-ranges", &num_ranges); + num_ranges = num_ranges / sizeof(*voltage_ranges) / 2; + if (!voltage_ranges || !num_ranges) { + dev_err(dev, "OF: voltage-ranges unspecified\n"); + goto err_ocr; + } + + for (i = 0; i < num_ranges; i++) { + const int j = i * 2; + u32 mask; + + mask = mmc_vddrange_to_ocrmask(voltage_ranges[j], + voltage_ranges[j + 1]); + if (!mask) { + ret = -EINVAL; + dev_err(dev, "OF: voltage-range #%d is invalid\n", i); + goto err_ocr; + } + oms->pdata.ocr_mask |= mask; + } + + for (i = 0; i < ARRAY_SIZE(oms->gpios); i++) { + enum of_gpio_flags gpio_flags; + + oms->gpios[i] = of_get_gpio_flags(np, i, &gpio_flags); + if (!gpio_is_valid(oms->gpios[i])) + continue; + + ret = gpio_request(oms->gpios[i], dev->bus_id); + if (ret < 0) { + oms->gpios[i] = -EINVAL; + continue; + } + + if (gpio_flags & OF_GPIO_ACTIVE_LOW) + oms->alow_gpios[i] = true; + } + + if (gpio_is_valid(oms->gpios[CD_GPIO])) + oms->pdata.get_cd = of_mmc_spi_get_cd; + if (gpio_is_valid(oms->gpios[WP_GPIO])) + oms->pdata.get_ro = of_mmc_spi_get_ro; + + /* We don't support interrupts yet, let's poll. */ + oms->pdata.caps |= MMC_CAP_NEEDS_POLL; + + dev->platform_data = &oms->pdata; + return dev->platform_data; +err_ocr: + kfree(oms); + return NULL; +} +EXPORT_SYMBOL(mmc_spi_get_pdata); + +void mmc_spi_put_pdata(struct spi_device *spi) +{ + struct device *dev = &spi->dev; + struct device_node *np = dev_archdata_get_node(&dev->archdata); + struct of_mmc_spi *oms = to_of_mmc_spi(dev); + int i; + + if (!dev->platform_data || !np) + return; + + for (i = 0; i < ARRAY_SIZE(oms->gpios); i++) { + if (gpio_is_valid(oms->gpios[i])) + gpio_free(oms->gpios[i]); + } + kfree(oms); + dev->platform_data = NULL; +} +EXPORT_SYMBOL(mmc_spi_put_pdata); |