Re: [PATCH 04/10] leds: lp5521: remove unnecessary writing commands

From: Bryan Wu
Date: Tue Aug 13 2013 - 16:43:07 EST


On Thu, Aug 8, 2013 at 12:59 AM, Milo Kim <woogyom.kim@xxxxxxxxx> wrote:
> This patch reduces the number of programming commands.
>
> (Count of sending commands)
> Old code: 32 + program size (32 counts for clearing program memory)
> New code: 32
>
> Pattern buffer is initialized to 0 in this function.
> Just update new program data and remaining buffers are filled with 0.
> So it's needless to clear whole area.
>

Good, I will merge this.
-Bryan

> Signed-off-by: Milo Kim <milo.kim@xxxxxx>
> ---
> drivers/leds/leds-lp5521.c | 14 +++-----------
> 1 file changed, 3 insertions(+), 11 deletions(-)
>
> diff --git a/drivers/leds/leds-lp5521.c b/drivers/leds/leds-lp5521.c
> index c00f922..0518835 100644
> --- a/drivers/leds/leds-lp5521.c
> +++ b/drivers/leds/leds-lp5521.c
> @@ -220,17 +220,11 @@ static int lp5521_update_program_memory(struct lp55xx_chip *chip,
> };
> unsigned cmd;
> char c[3];
> - int program_size;
> int nrchars;
> - int offset = 0;
> int ret;
> - int i;
> -
> - /* clear program memory before updating */
> - for (i = 0; i < LP5521_PROGRAM_LENGTH; i++)
> - lp55xx_write(chip, addr[idx] + i, 0);
> + int offset = 0;
> + int i = 0;
>
> - i = 0;
> while ((offset < size - 1) && (i < LP5521_PROGRAM_LENGTH)) {
> /* separate sscanfs because length is working only for %s */
> ret = sscanf(data + offset, "%2s%n ", c, &nrchars);
> @@ -250,11 +244,9 @@ static int lp5521_update_program_memory(struct lp55xx_chip *chip,
> if (i % 2)
> goto err;
>
> - program_size = i;
> -
> mutex_lock(&chip->lock);
>
> - for (i = 0; i < program_size; i++) {
> + for (i = 0; i < LP5521_PROGRAM_LENGTH; i++) {
> ret = lp55xx_write(chip, addr[idx] + i, pattern[i]);
> if (ret) {
> mutex_unlock(&chip->lock);
> --
> 1.7.9.5
>
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