2021-11-16 00:08:16

by Marijn Suijten

Subject: [PATCH v3 3/9] backlight: qcom-wled: Use cpu_to_le16 macro to perform conversion

The kernel already provides appropriate primitives to perform endianness
conversion which should be used in favour of manual bit-wrangling.

Signed-off-by: Marijn Suijten <[email protected]>
Reviewed-by: AngeloGioacchino Del Regno <[email protected]>
---
drivers/video/backlight/qcom-wled.c | 23 +++++++++++------------
1 file changed, 11 insertions(+), 12 deletions(-)

diff --git a/drivers/video/backlight/qcom-wled.c b/drivers/video/backlight/qcom-wled.c
index d413b913fef3..9d883e702134 100644
--- a/drivers/video/backlight/qcom-wled.c
+++ b/drivers/video/backlight/qcom-wled.c
@@ -231,14 +231,14 @@ struct wled {
static int wled3_set_brightness(struct wled *wled, u16 brightness)
{
int rc, i;
- u8 v[2];
+ __le16 v;

- v[0] = brightness & 0xff;
- v[1] = (brightness >> 8) & 0xf;
+ v = cpu_to_le16(brightness & WLED3_SINK_REG_BRIGHT_MAX);

for (i = 0; i < wled->cfg.num_strings; ++i) {
rc = regmap_bulk_write(wled->regmap, wled->ctrl_addr +
- WLED3_SINK_REG_BRIGHT(i), v, 2);
+ WLED3_SINK_REG_BRIGHT(i),
+ &v, sizeof(v));
if (rc < 0)
return rc;
}
@@ -250,18 +250,18 @@ static int wled4_set_brightness(struct wled *wled, u16 brightness)
{
int rc, i;
u16 low_limit = wled->max_brightness * 4 / 1000;
- u8 v[2];
+ __le16 v;

/* WLED4's lower limit of operation is 0.4% */
if (brightness > 0 && brightness < low_limit)
brightness = low_limit;

- v[0] = brightness & 0xff;
- v[1] = (brightness >> 8) & 0xf;
+ v = cpu_to_le16(brightness & WLED3_SINK_REG_BRIGHT_MAX);

for (i = 0; i < wled->cfg.num_strings; ++i) {
rc = regmap_bulk_write(wled->regmap, wled->sink_addr +
- WLED4_SINK_REG_BRIGHT(i), v, 2);
+ WLED4_SINK_REG_BRIGHT(i),
+ &v, sizeof(v));
if (rc < 0)
return rc;
}
@@ -273,21 +273,20 @@ static int wled5_set_brightness(struct wled *wled, u16 brightness)
{
int rc, offset;
u16 low_limit = wled->max_brightness * 1 / 1000;
- u8 v[2];
+ __le16 v;

/* WLED5's lower limit is 0.1% */
if (brightness < low_limit)
brightness = low_limit;

- v[0] = brightness & 0xff;
- v[1] = (brightness >> 8) & 0x7f;
+ v = cpu_to_le16(brightness & WLED5_SINK_REG_BRIGHT_MAX_15B);

offset = (wled->cfg.mod_sel == MOD_A) ?
WLED5_SINK_REG_MOD_A_BRIGHTNESS_LSB :
WLED5_SINK_REG_MOD_B_BRIGHTNESS_LSB;

rc = regmap_bulk_write(wled->regmap, wled->sink_addr + offset,
- v, 2);
+ &v, sizeof(v));
return rc;
}

--
2.33.1

2021-11-16 11:56:57

by Daniel Thompson

Subject: Re: [PATCH v3 3/9] backlight: qcom-wled: Use cpu_to_le16 macro to perform conversion

On Mon, Nov 15, 2021 at 09:34:53PM +0100, Marijn Suijten wrote:
> The kernel already provides appropriate primitives to perform endianness
> conversion which should be used in favour of manual bit-wrangling.
>
> Signed-off-by: Marijn Suijten <[email protected]>
> Reviewed-by: AngeloGioacchino Del Regno <[email protected]>

Reviewed-by: Daniel Thompson <[email protected]>


Daniel.

2021-12-22 11:16:30

by Lee Jones

Subject: Re: [PATCH v3 3/9] backlight: qcom-wled: Use cpu_to_le16 macro to perform conversion

On Mon, 15 Nov 2021, Marijn Suijten wrote:

> The kernel already provides appropriate primitives to perform endianness
> conversion which should be used in favour of manual bit-wrangling.
>
> Signed-off-by: Marijn Suijten <[email protected]>
> Reviewed-by: AngeloGioacchino Del Regno <[email protected]>
> ---
> drivers/video/backlight/qcom-wled.c | 23 +++++++++++------------
> 1 file changed, 11 insertions(+), 12 deletions(-)

Applied, thanks.

--
Lee Jones [李琼斯]
Senior Technical Lead - Developer Services
Linaro.org │ Open source software for Arm SoCs
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