[PATCH 3/3] mmc: mmc_spi: Document the 3 local functions

Jaehoon Chung
2021-02-01T04:53:15Z

> mmc_spi_sendcmd(), mmc_spi_readdata() and mmc_spi_writedata() are
> currently undocumented. Add comment blocks to explain the arguments
> and the return value.
>
> Signed-off-by: Bin Meng <bin.meng@windriver.com>

Reviewed-by: Jaehoon Chung <jh80.chung@samsung.com>

Best Regards,
Jaehoon Chung

> ---
>
> drivers/mmc/mmc_spi.c | 36 +++++++++++++++++++++++++++++++++++-
> 1 file changed, 35 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/mmc/mmc_spi.c b/drivers/mmc/mmc_spi.c
> index 5ec6b0f..6d4f205 100644
> --- a/drivers/mmc/mmc_spi.c
> +++ b/drivers/mmc/mmc_spi.c
> @@ -37,7 +37,8 @@
> #define SPI_RESPONSE_CRC_ERR ((5 << 1)|1)
> #define SPI_RESPONSE_WRITE_ERR ((6 << 1)|1)
>
> -/* Read and write blocks start with these tokens and end with crc;
> +/*
> + * Read and write blocks start with these tokens and end with crc;
> * on error, read tokens act like a subset of R2_SPI_* values.
> */
> /* single block write multiblock read */
> @@ -70,6 +71,20 @@ struct mmc_spi_priv {
> struct spi_slave *spi;
> };
>
> +/**
> + * mmc_spi_sendcmd() - send a command to the SD card
> + *
> + * @dev: mmc_spi device
> + * @cmdidx: command index
> + * @cmdarg: command argument
> + * @resp_type: card response type
> + * @resp: buffer to store the card response
> + * @resp_size: size of the card response
> + * @resp_match: if true, compare each of received bytes with @resp_match_value
> + * @resp_match_value: a value to be compared with each of received bytes
> + * @r1b: if true, receive additional bytes for busy signal token
> + * @return 0 if OK, -ETIMEDOUT if no card response is received, -ve on error
> + */
> static int mmc_spi_sendcmd(struct udevice *dev,
> ushort cmdidx, u32 cmdarg, u32 resp_type,
> u8 *resp, u32 resp_size,
> @@ -159,6 +174,15 @@ static int mmc_spi_sendcmd(struct udevice *dev,
> return 0;
> }
>
> +/**
> + * mmc_spi_readdata() - read data block(s) from the SD card
> + *
> + * @dev: mmc_spi device
> + * @xbuf: buffer of the actual data (excluding token and crc) to read
> + * @bcnt: number of data blocks to transfer
> + * @bsize: size of the actual data (excluding token and crc) in bytes
> + * @return 0 if OK, -ECOMM if crc error, -ETIMEDOUT on other errors
> + */
> static int mmc_spi_readdata(struct udevice *dev,
> void *xbuf, u32 bcnt, u32 bsize)
> {
> @@ -207,6 +231,16 @@ static int mmc_spi_readdata(struct udevice *dev,
> return ret;
> }
>
> +/**
> + * mmc_spi_writedata() - write data block(s) to the SD card
> + *
> + * @dev: mmc_spi device
> + * @xbuf: buffer of the actual data (excluding token and crc) to write
> + * @bcnt: number of data blocks to transfer
> + * @bsize: size of actual data (excluding token and crc) in bytes
> + * @multi: indicate a transfer by multiple block write command (CMD25)
> + * @return 0 if OK, -ECOMM if crc error, -ETIMEDOUT on other errors
> + */
> static int mmc_spi_writedata(struct udevice *dev, const void *xbuf,
> u32 bcnt, u32 bsize, int multi)
> {
>