Pierre Ossman | 46f555f | 2007-05-27 12:57:15 +0200 | [diff] [blame^] | 1 | /* |
| 2 | * linux/drivers/mmc/core/sdio_io.c |
| 3 | * |
| 4 | * Copyright 2007 Pierre Ossman |
| 5 | * |
| 6 | * This program is free software; you can redistribute it and/or modify |
| 7 | * it under the terms of the GNU General Public License as published by |
| 8 | * the Free Software Foundation; either version 2 of the License, or (at |
| 9 | * your option) any later version. |
| 10 | */ |
| 11 | |
| 12 | #include <linux/mmc/host.h> |
| 13 | #include <linux/mmc/card.h> |
| 14 | #include <linux/mmc/sdio_func.h> |
| 15 | |
| 16 | #include "sdio_ops.h" |
| 17 | |
| 18 | /** |
| 19 | * sdio_claim_host - exclusively claim a bus for a certain SDIO function |
| 20 | * @func: SDIO function that will be accessed |
| 21 | * |
| 22 | * Claim a bus for a set of operations. The SDIO function given |
| 23 | * is used to figure out which bus is relevant. |
| 24 | */ |
| 25 | void sdio_claim_host(struct sdio_func *func) |
| 26 | { |
| 27 | BUG_ON(!func); |
| 28 | BUG_ON(!func->card); |
| 29 | |
| 30 | mmc_claim_host(func->card->host); |
| 31 | } |
| 32 | EXPORT_SYMBOL_GPL(sdio_claim_host); |
| 33 | |
| 34 | /** |
| 35 | * sdio_release_host - release a bus for a certain SDIO function |
| 36 | * @func: SDIO function that was accessed |
| 37 | * |
| 38 | * Release a bus, allowing others to claim the bus for their |
| 39 | * operations. |
| 40 | */ |
| 41 | void sdio_release_host(struct sdio_func *func) |
| 42 | { |
| 43 | BUG_ON(!func); |
| 44 | BUG_ON(!func->card); |
| 45 | |
| 46 | mmc_release_host(func->card->host); |
| 47 | } |
| 48 | EXPORT_SYMBOL_GPL(sdio_release_host); |
| 49 | |
| 50 | /** |
| 51 | * sdio_readb - read a single byte from a SDIO function |
| 52 | * @func: SDIO function to access |
| 53 | * @addr: address to read |
| 54 | * @err_ret: optional status value from transfer |
| 55 | * |
| 56 | * Reads a single byte from the address space of a given SDIO |
| 57 | * function. If there is a problem reading the address, 0xff |
| 58 | * is returned and @err_ret will contain the error code. |
| 59 | */ |
| 60 | unsigned char sdio_readb(struct sdio_func *func, unsigned int addr, |
| 61 | int *err_ret) |
| 62 | { |
| 63 | int ret; |
| 64 | unsigned char val; |
| 65 | |
| 66 | BUG_ON(!func); |
| 67 | |
| 68 | if (err_ret) |
| 69 | *err_ret = 0; |
| 70 | |
| 71 | ret = mmc_io_rw_direct(func->card, 0, func->num, addr, 0, &val); |
| 72 | if (ret) { |
| 73 | if (err_ret) |
| 74 | *err_ret = ret; |
| 75 | return 0xFF; |
| 76 | } |
| 77 | |
| 78 | return val; |
| 79 | } |
| 80 | EXPORT_SYMBOL_GPL(sdio_readb); |
| 81 | |
| 82 | /** |
| 83 | * sdio_writeb - write a single byte to a SDIO function |
| 84 | * @func: SDIO function to access |
| 85 | * @b: byte to write |
| 86 | * @addr: address to write to |
| 87 | * @err_ret: optional status value from transfer |
| 88 | * |
| 89 | * Writes a single byte to the address space of a given SDIO |
| 90 | * function. @err_ret will contain the status of the actual |
| 91 | * transfer. |
| 92 | */ |
| 93 | void sdio_writeb(struct sdio_func *func, unsigned char b, unsigned int addr, |
| 94 | int *err_ret) |
| 95 | { |
| 96 | int ret; |
| 97 | |
| 98 | BUG_ON(!func); |
| 99 | |
| 100 | ret = mmc_io_rw_direct(func->card, 1, func->num, addr, b, NULL); |
| 101 | if (err_ret) |
| 102 | *err_ret = ret; |
| 103 | } |
| 104 | EXPORT_SYMBOL_GPL(sdio_writeb); |
| 105 | |