On Fri, May 6, 2022 at 2:18 PM Joel Selvaraj <jo@xxxxxxxxxxx> wrote:
> Add DRM panel driver for EBBG FT8719 6.18" 2246x1080 DSI video mode
> panel, which can be found on some Xiaomi Poco F1 phones. The panel's
> backlight is managed through QCOM WLED driver.
>
> Signed-off-by: Joel Selvaraj <jo@xxxxxxxxxxx>
Cool!
> +#define dsi_generic_write_seq(dsi, seq...) do { \
> + static const u8 d[] = { seq }; \
> + int ret; \
> + ret = mipi_dsi_generic_write(dsi, d, ARRAY_SIZE(d)); \
> + if (ret < 0) \
> + return ret; \
> + } while (0)
> +
> +#define dsi_dcs_write_seq(dsi, seq...) do { \
> + static const u8 d[] = { seq }; \
> + int ret; \
> + ret = mipi_dsi_dcs_write_buffer(dsi, d, ARRAY_SIZE(d)); \
> + if (ret < 0) \
> + return ret; \
> + } while (0)
First I don't see what the do {} while (0) buys you, just use
a basic block {}.
Second look at mipi_dbi_command() in include/drm/drm_mipi_dbi.h
this is very similar.
So this utility macro should be in a generic file such as
include/drm/drm_mipi_dsi.h. (Can be added in a separate
patch.)
Third I think you need only one macro (see below).
> +static int ebbg_ft8719_on(struct ebbg_ft8719 *ctx)
> +{
> + struct mipi_dsi_device *dsi = ctx->dsi;
> + struct device *dev = &dsi->dev;
> + int ret;
> +
> + dsi->mode_flags |= MIPI_DSI_MODE_LPM;
> +
> + dsi_dcs_write_seq(dsi, 0x00, 0x00);
> + dsi_generic_write_seq(dsi, 0xff, 0x87, 0x19, 0x01);
It's dubious that you always have dsi_dcs_write_seq()
followed by dsi_generic_write_seq().
That means mipi_dsi_generic_write() followed by
mipi_dsi_dcs_write_buffer(). But if you look at these
commands in drivers/gpu/drm/drm_mipi_dsi.c
you see that they do the same thing!
Doesn't it work to combine them into one call for each
pair?
> + dsi_dcs_write_seq(dsi, 0x00, 0x80);
> + dsi_generic_write_seq(dsi, 0xff, 0x87, 0x19);
Lots of magic numbers. You don't have a datasheet do you?
So you could #define some of the magic?
> + if (ctx->prepared)
> + return 0;
(...)
> + ctx->prepared = true;
> + return 0;
(...)
> + if (!ctx->prepared)
> + return 0;
(...)
> + ctx->prepared = false;
> + return 0;
Drop this state variable it is a reimplementation of something
that the core will track for you.
The rest looks nice!
Yours,
Linus Walleij
