diff options
| -rw-r--r-- | drivers/mmc/core/sdio_io.c | 64 | ||||
| -rw-r--r-- | include/linux/mmc/sdio_func.h | 5 |
2 files changed, 69 insertions, 0 deletions
diff --git a/drivers/mmc/core/sdio_io.c b/drivers/mmc/core/sdio_io.c index 34b085d4024a..625b92ce9cef 100644 --- a/drivers/mmc/core/sdio_io.c +++ b/drivers/mmc/core/sdio_io.c @@ -482,3 +482,67 @@ void sdio_writel(struct sdio_func *func, unsigned long b, unsigned int addr, } EXPORT_SYMBOL_GPL(sdio_writel); +/** + * sdio_f0_readb - read a single byte from SDIO function 0 + * @func: an SDIO function of the card + * @addr: address to read + * @err_ret: optional status value from transfer + * + * Reads a single byte from the address space of SDIO function 0. + * If there is a problem reading the address, 0xff is returned + * and @err_ret will contain the error code. + */ +unsigned char sdio_f0_readb(struct sdio_func *func, unsigned int addr, + int *err_ret) +{ + int ret; + unsigned char val; + + BUG_ON(!func); + + if (err_ret) + *err_ret = 0; + + ret = mmc_io_rw_direct(func->card, 0, 0, addr, 0, &val); + if (ret) { + if (err_ret) + *err_ret = ret; + return 0xFF; + } + + return val; +} +EXPORT_SYMBOL_GPL(sdio_f0_readb); + +/** + * sdio_f0_writeb - write a single byte to SDIO function 0 + * @func: an SDIO function of the card + * @b: byte to write + * @addr: address to write to + * @err_ret: optional status value from transfer + * + * Writes a single byte to the address space of SDIO function 0. + * @err_ret will contain the status of the actual transfer. + * + * Only writes to the vendor specific CCCR registers (0xF0 - + * 0xFF) are permiited; @err_ret will be set to -EINVAL for * + * writes outside this range. + */ +void sdio_f0_writeb(struct sdio_func *func, unsigned char b, unsigned int addr, + int *err_ret) +{ + int ret; + + BUG_ON(!func); + + if (addr < 0xF0 || addr > 0xFF) { + if (err_ret) + *err_ret = -EINVAL; + return; + } + + ret = mmc_io_rw_direct(func->card, 1, 0, addr, b, NULL); + if (err_ret) + *err_ret = ret; +} +EXPORT_SYMBOL_GPL(sdio_f0_writeb); diff --git a/include/linux/mmc/sdio_func.h b/include/linux/mmc/sdio_func.h index f05757984e8d..da6a96c39776 100644 --- a/include/linux/mmc/sdio_func.h +++ b/include/linux/mmc/sdio_func.h @@ -141,5 +141,10 @@ extern int sdio_memcpy_toio(struct sdio_func *func, unsigned int addr, extern int sdio_writesb(struct sdio_func *func, unsigned int addr, void *src, int count); +extern unsigned char sdio_f0_readb(struct sdio_func *func, + unsigned int addr, int *err_ret); +extern void sdio_f0_writeb(struct sdio_func *func, unsigned char b, + unsigned int addr, int *err_ret); + #endif |