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_name(dev)); 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); 150