Anton Vorontsov | 9c43df5 | 2008-12-30 18:15:28 +0300 | [diff] [blame] | 1 | /* |
| 2 | * OpenFirmware bindings for the MMC-over-SPI driver |
| 3 | * |
| 4 | * Copyright (c) MontaVista Software, Inc. 2008. |
| 5 | * |
| 6 | * Author: Anton Vorontsov <avorontsov@ru.mvista.com> |
| 7 | * |
| 8 | * This program is free software; you can redistribute it and/or modify it |
| 9 | * under the terms of the GNU General Public License as published by the |
| 10 | * Free Software Foundation; either version 2 of the License, or (at your |
| 11 | * option) any later version. |
| 12 | */ |
| 13 | |
| 14 | #include <linux/kernel.h> |
| 15 | #include <linux/module.h> |
| 16 | #include <linux/device.h> |
| 17 | #include <linux/gpio.h> |
| 18 | #include <linux/of.h> |
| 19 | #include <linux/of_gpio.h> |
| 20 | #include <linux/spi/spi.h> |
| 21 | #include <linux/spi/mmc_spi.h> |
| 22 | #include <linux/mmc/core.h> |
| 23 | #include <linux/mmc/host.h> |
| 24 | |
| 25 | enum { |
| 26 | CD_GPIO = 0, |
| 27 | WP_GPIO, |
| 28 | NUM_GPIOS, |
| 29 | }; |
| 30 | |
| 31 | struct of_mmc_spi { |
| 32 | int gpios[NUM_GPIOS]; |
| 33 | bool alow_gpios[NUM_GPIOS]; |
| 34 | struct mmc_spi_platform_data pdata; |
| 35 | }; |
| 36 | |
| 37 | static struct of_mmc_spi *to_of_mmc_spi(struct device *dev) |
| 38 | { |
| 39 | return container_of(dev->platform_data, struct of_mmc_spi, pdata); |
| 40 | } |
| 41 | |
| 42 | static int of_mmc_spi_read_gpio(struct device *dev, int gpio_num) |
| 43 | { |
| 44 | struct of_mmc_spi *oms = to_of_mmc_spi(dev); |
| 45 | bool active_low = oms->alow_gpios[gpio_num]; |
| 46 | bool value = gpio_get_value(oms->gpios[gpio_num]); |
| 47 | |
| 48 | return active_low ^ value; |
| 49 | } |
| 50 | |
| 51 | static int of_mmc_spi_get_cd(struct device *dev) |
| 52 | { |
| 53 | return of_mmc_spi_read_gpio(dev, CD_GPIO); |
| 54 | } |
| 55 | |
| 56 | static int of_mmc_spi_get_ro(struct device *dev) |
| 57 | { |
| 58 | return of_mmc_spi_read_gpio(dev, WP_GPIO); |
| 59 | } |
| 60 | |
| 61 | struct mmc_spi_platform_data *mmc_spi_get_pdata(struct spi_device *spi) |
| 62 | { |
| 63 | struct device *dev = &spi->dev; |
| 64 | struct device_node *np = dev_archdata_get_node(&dev->archdata); |
| 65 | struct of_mmc_spi *oms; |
| 66 | const u32 *voltage_ranges; |
| 67 | int num_ranges; |
| 68 | int i; |
| 69 | int ret = -EINVAL; |
| 70 | |
| 71 | if (dev->platform_data || !np) |
| 72 | return dev->platform_data; |
| 73 | |
| 74 | oms = kzalloc(sizeof(*oms), GFP_KERNEL); |
| 75 | if (!oms) |
| 76 | return NULL; |
| 77 | |
| 78 | voltage_ranges = of_get_property(np, "voltage-ranges", &num_ranges); |
| 79 | num_ranges = num_ranges / sizeof(*voltage_ranges) / 2; |
| 80 | if (!voltage_ranges || !num_ranges) { |
| 81 | dev_err(dev, "OF: voltage-ranges unspecified\n"); |
| 82 | goto err_ocr; |
| 83 | } |
| 84 | |
| 85 | for (i = 0; i < num_ranges; i++) { |
| 86 | const int j = i * 2; |
| 87 | u32 mask; |
| 88 | |
| 89 | mask = mmc_vddrange_to_ocrmask(voltage_ranges[j], |
| 90 | voltage_ranges[j + 1]); |
| 91 | if (!mask) { |
| 92 | ret = -EINVAL; |
| 93 | dev_err(dev, "OF: voltage-range #%d is invalid\n", i); |
| 94 | goto err_ocr; |
| 95 | } |
| 96 | oms->pdata.ocr_mask |= mask; |
| 97 | } |
| 98 | |
| 99 | for (i = 0; i < ARRAY_SIZE(oms->gpios); i++) { |
| 100 | enum of_gpio_flags gpio_flags; |
| 101 | |
| 102 | oms->gpios[i] = of_get_gpio_flags(np, i, &gpio_flags); |
| 103 | if (!gpio_is_valid(oms->gpios[i])) |
| 104 | continue; |
| 105 | |
| 106 | ret = gpio_request(oms->gpios[i], dev->bus_id); |
| 107 | if (ret < 0) { |
| 108 | oms->gpios[i] = -EINVAL; |
| 109 | continue; |
| 110 | } |
| 111 | |
| 112 | if (gpio_flags & OF_GPIO_ACTIVE_LOW) |
| 113 | oms->alow_gpios[i] = true; |
| 114 | } |
| 115 | |
| 116 | if (gpio_is_valid(oms->gpios[CD_GPIO])) |
| 117 | oms->pdata.get_cd = of_mmc_spi_get_cd; |
| 118 | if (gpio_is_valid(oms->gpios[WP_GPIO])) |
| 119 | oms->pdata.get_ro = of_mmc_spi_get_ro; |
| 120 | |
| 121 | /* We don't support interrupts yet, let's poll. */ |
| 122 | oms->pdata.caps |= MMC_CAP_NEEDS_POLL; |
| 123 | |
| 124 | dev->platform_data = &oms->pdata; |
| 125 | return dev->platform_data; |
| 126 | err_ocr: |
| 127 | kfree(oms); |
| 128 | return NULL; |
| 129 | } |
| 130 | EXPORT_SYMBOL(mmc_spi_get_pdata); |
| 131 | |
| 132 | void mmc_spi_put_pdata(struct spi_device *spi) |
| 133 | { |
| 134 | struct device *dev = &spi->dev; |
| 135 | struct device_node *np = dev_archdata_get_node(&dev->archdata); |
| 136 | struct of_mmc_spi *oms = to_of_mmc_spi(dev); |
| 137 | int i; |
| 138 | |
| 139 | if (!dev->platform_data || !np) |
| 140 | return; |
| 141 | |
| 142 | for (i = 0; i < ARRAY_SIZE(oms->gpios); i++) { |
| 143 | if (gpio_is_valid(oms->gpios[i])) |
| 144 | gpio_free(oms->gpios[i]); |
| 145 | } |
| 146 | kfree(oms); |
| 147 | dev->platform_data = NULL; |
| 148 | } |
| 149 | EXPORT_SYMBOL(mmc_spi_put_pdata); |