Commit a368b408 authored by Miquel Raynal's avatar Miquel Raynal Committed by Neil Armstrong
Browse files

drm/panel: sitronix-st7789v: Clarify a definition 



The Sitronix datasheet explains BIT(1) of the RGBCTRL register as the
DOTCLK/PCLK edge used to sample the data lines:

    “0” The data is input on the positive edge of DOTCLK
    “1” The data is input on the negative edge of DOTCLK

IOW, this bit implies a falling edge and not a high state. Correct the
definition to ease the comparison with the datasheet.

Signed-off-by: default avatarMiquel Raynal <miquel.raynal@bootlin.com>
Acked-by: default avatarMaxime Ripard <mripard@kernel.org>
Reviewed-by: default avatarSebastian Reichel <sre@kernel.org>
Tested-by: default avatarSebastian Reichel <sre@kernel.org>
Signed-off-by: default avatarSebastian Reichel <sre@kernel.org>
Signed-off-by: default avatarNeil Armstrong <neil.armstrong@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20230714013756.1546769-18-sre@kernel.org
parent 6b00e72e

drivers/gpu/drm/panel/panel-sitronix-st7789v.c

+2 −2
Original line number Diff line number Diff line
@@ -27,7 +27,7 @@ 
#define ST7789V_RGBCTRL_RCM(n)			(((n) & 3) << 5)

#define ST7789V_RGBCTRL_VSYNC_HIGH		BIT(3)

#define ST7789V_RGBCTRL_HSYNC_HIGH		BIT(2)

#define ST7789V_RGBCTRL_PCLK_HIGH		BIT(1)

#define ST7789V_RGBCTRL_PCLK_FALLING		BIT(1)

#define ST7789V_RGBCTRL_DE_LOW			BIT(0)

#define ST7789V_RGBCTRL_VBP(n)			((n) & 0x7f)

#define ST7789V_RGBCTRL_HBP(n)			((n) & 0x1f)
@@ -259,7 +259,7 @@ static int st7789v_prepare(struct drm_panel *panel) 
	if (ctx->info->mode->flags & DRM_MODE_FLAG_PHSYNC)

		polarity |= ST7789V_RGBCTRL_HSYNC_HIGH;

	if (ctx->info->bus_flags & DRM_BUS_FLAG_PIXDATA_SAMPLE_NEGEDGE)

		polarity |= ST7789V_RGBCTRL_PCLK_HIGH;

		polarity |= ST7789V_RGBCTRL_PCLK_FALLING;

	if (ctx->info->bus_flags & DRM_BUS_FLAG_DE_LOW)

		polarity |= ST7789V_RGBCTRL_DE_LOW;