Re: [PATCH v6 1/2] media: imx274: use regmap_bulk_write to write multybyte registers

From: Philippe De Muyter
Date: Tue Aug 28 2018 - 05:03:06 EST


On Wed, Jul 25, 2018 at 06:24:54PM +0200, Luca Ceresoli wrote:
> Currently 2-bytes and 3-bytes registers are set by very similar
> functions doing the needed shift & mask manipulation, followed by very
> similar for loops setting one byte at a time over I2C.
>
> Replace all of this code by a unique helper function that calls
> regmap_bulk_write(), which has two advantages:
> - sets all the bytes in a unique I2C transaction
> - removes lots of now unused code.
>
> Signed-off-by: Luca Ceresoli <luca@xxxxxxxxxxxxxxxx>
> Cc: Sakari Ailus <sakari.ailus@xxxxxxxxxxxxxxx>
>
...
> +/**
> + * Write a multibyte register.
> + *
> + * Uses a bulk write where possible.
> + *
> + * @priv: Pointer to device structure
> + * @addr: Address of the LSB register. Other registers must be
> + * consecutive, least-to-most significant.
> + * @val: Value to be written to the register (cpu endianness)
> + * @nbytes: Number of bits to write (range: [1..3])
> + */
> +static int imx274_write_mbreg(struct stimx274 *priv, u16 addr, u32 val,
> + size_t nbytes)

Should nbytes be called nbits, or is nbytes a 'Number of bytes' ?

Philippe
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