Hi,
On Wed, Oct 19, 2022 at 10:52:14AM +0800, xinlei.lee@xxxxxxxxxxxx wrote:
> From: Xinlei Lee <xinlei.lee@xxxxxxxxxxxx>
>
> The difference between MT8186 and other ICs is that when modifying the
> output format, we need to modify the mmsys_base+0x400 register to take
> effect.
> So when setting the dpi output format, we need to call mmsys_func to set
mmsys_func isn't something that exists in the code. Instead mention the actual
function name: mtk_mmsys_ddp_dpi_fmt_config.
> it to MT8186 synchronously.
Here, before saying that the commit adds all the settings for dpi, you could
have mentioned that the previous commit lacked those, to make it clearer:
Commit a071e52f75d1 ("soc: mediatek: Add mmsys func to adapt to dpi output for MT8186")
lacked some of the possible output formats and also had a wrong bitmask.
> Adding mmsys all the settings that need to be modified with dpi are for
> mt8186.
This sentence I would change to the following one:
Add the missing output formats and fix the bitmask.
Finally, you're also making the function more HW-agnostic (although in my
opinion this could've been a future separate commit), so it's worth mentioning
it here:
While at it, also update mtk_mmsys_ddp_dpi_fmt_config() to use generic formats,
so that it is slightly easier to extend for other platforms.
>
> Fixes: a071e52f75d1 ("soc: mediatek: Add mmsys func to adapt to dpi
> output for MT8186")
The fixes tag should be kept in a single line, without wrapping.
>
> Signed-off-by: Xinlei Lee <xinlei.lee@xxxxxxxxxxxx>
> Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@xxxxxxxxxxxxx>
> Reviewed-by: CK Hu <ck.hu@xxxxxxxxxxxx>
> ---
> drivers/soc/mediatek/mt8186-mmsys.h | 8 +++++---
> drivers/soc/mediatek/mtk-mmsys.c | 27 ++++++++++++++++++++------
> include/linux/soc/mediatek/mtk-mmsys.h | 7 +++++++
> 3 files changed, 33 insertions(+), 9 deletions(-)
>
> diff --git a/drivers/soc/mediatek/mt8186-mmsys.h b/drivers/soc/mediatek/mt8186-mmsys.h
> index 09b1ccbc0093..035aec1eb616 100644
> --- a/drivers/soc/mediatek/mt8186-mmsys.h
> +++ b/drivers/soc/mediatek/mt8186-mmsys.h
> @@ -5,9 +5,11 @@
>
> /* Values for DPI configuration in MMSYS address space */
> #define MT8186_MMSYS_DPI_OUTPUT_FORMAT 0x400
> -#define DPI_FORMAT_MASK 0x1
> -#define DPI_RGB888_DDR_CON BIT(0)
> -#define DPI_RGB565_SDR_CON BIT(1)
> +#define DPI_FORMAT_MASK GENMASK(1, 0)
> +#define DPI_RGB888_SDR_CON 0
> +#define DPI_RGB888_DDR_CON 1
> +#define DPI_RGB565_SDR_CON 2
> +#define DPI_RGB565_DDR_CON 3
These defines should all have a MT8186_ prefix. This will avoid confusions now
that mtk_mmsys_ddp_dpi_fmt_config() is being made more platform-agnostic.
>
> #define MT8186_MMSYS_OVL_CON 0xF04
> #define MT8186_MMSYS_OVL0_CON_MASK 0x3
> diff --git a/drivers/soc/mediatek/mtk-mmsys.c b/drivers/soc/mediatek/mtk-mmsys.c
> index d2c7a87aab87..205f6de45851 100644
> --- a/drivers/soc/mediatek/mtk-mmsys.c
> +++ b/drivers/soc/mediatek/mtk-mmsys.c
> @@ -238,12 +238,27 @@ static void mtk_mmsys_update_bits(struct mtk_mmsys *mmsys, u32 offset, u32 mask,
>
> void mtk_mmsys_ddp_dpi_fmt_config(struct device *dev, u32 val)
> {
> - if (val)
> - mtk_mmsys_update_bits(dev_get_drvdata(dev), MT8186_MMSYS_DPI_OUTPUT_FORMAT,
> - DPI_RGB888_DDR_CON, DPI_FORMAT_MASK);
> - else
> - mtk_mmsys_update_bits(dev_get_drvdata(dev), MT8186_MMSYS_DPI_OUTPUT_FORMAT,
> - DPI_RGB565_SDR_CON, DPI_FORMAT_MASK);
> + struct mtk_mmsys *mmsys = dev_get_drvdata(dev);
> +
> + switch (val) {
> + case MTK_DPI_RGB888_SDR_CON:
> + mtk_mmsys_update_bits(mmsys, MT8186_MMSYS_DPI_OUTPUT_FORMAT,
> + DPI_FORMAT_MASK, DPI_RGB888_SDR_CON);
> + break;
> + case MTK_DPI_RGB565_SDR_CON:
> + mtk_mmsys_update_bits(mmsys, MT8186_MMSYS_DPI_OUTPUT_FORMAT,
> + DPI_FORMAT_MASK, DPI_RGB565_SDR_CON);
> + break;
> + case MTK_DPI_RGB565_DDR_CON:
> + mtk_mmsys_update_bits(mmsys, MT8186_MMSYS_DPI_OUTPUT_FORMAT,
> + DPI_FORMAT_MASK, DPI_RGB565_DDR_CON);
> + break;
> + case MTK_DPI_RGB888_DDR_CON:
> + default:
> + mtk_mmsys_update_bits(mmsys, MT8186_MMSYS_DPI_OUTPUT_FORMAT,
> + DPI_FORMAT_MASK, DPI_RGB888_DDR_CON);
> + break;
> + }
To be honest I don't really see the point of making the function slightly more
platform-agnostic like this. With a single platform making use of it it's just
an unneeded extra abstraction, and it could easily be done when a second
platform starts requiring this as well...
In any case,
Reviewed-by: Nícolas F. R. A. Prado <nfraprado@xxxxxxxxxxxxx>
Thanks,
Nícolas
> }
[..]
