This adds code to send read commands to read a single byte from the display, in order to perform MTP ID look-up of the mounted panel on the s6e63m0 controller. This is needed for proper biasing on the DSI variants.
Cc: Stephan Gerhold stephan@gerhold.net Cc: Paweł Chmiel pawel.mikolaj.chmiel@gmail.com Signed-off-by: Linus Walleij linus.walleij@linaro.org --- .../gpu/drm/panel/panel-samsung-s6e63m0-dsi.c | 19 ++++++++++++++++++- .../gpu/drm/panel/panel-samsung-s6e63m0-spi.c | 14 +++++++++++++- drivers/gpu/drm/panel/panel-samsung-s6e63m0.c | 11 +++++++++++ drivers/gpu/drm/panel/panel-samsung-s6e63m0.h | 1 + 4 files changed, 43 insertions(+), 2 deletions(-)
diff --git a/drivers/gpu/drm/panel/panel-samsung-s6e63m0-dsi.c b/drivers/gpu/drm/panel/panel-samsung-s6e63m0-dsi.c index f4927a6ce26d..2ec9e7900791 100644 --- a/drivers/gpu/drm/panel/panel-samsung-s6e63m0-dsi.c +++ b/drivers/gpu/drm/panel/panel-samsung-s6e63m0-dsi.c @@ -16,6 +16,22 @@ #define MCS_GLOBAL_PARAM 0xb0 #define S6E63M0_DSI_MAX_CHUNK 15 /* CMD + 15 bytes max */
+static int s6e63m0_dsi_dcs_read(struct device *dev, const u8 cmd, u8 *data) +{ + struct mipi_dsi_device *dsi = to_mipi_dsi_device(dev); + int ret; + + ret = mipi_dsi_dcs_read(dsi, cmd, data, 1); + if (ret < 0) { + DRM_DEV_ERROR(dev, "could not read DCS CMD %02x\n", cmd); + return ret; + } + + DRM_DEV_INFO(dev, "DSI read CMD %02x = %02x\n", cmd, *data); + + return 0; +} + static int s6e63m0_dsi_dcs_write(struct device *dev, const u8 *data, size_t len) { struct mipi_dsi_device *dsi = to_mipi_dsi_device(dev); @@ -90,7 +106,8 @@ static int s6e63m0_dsi_probe(struct mipi_dsi_device *dsi) MIPI_DSI_MODE_EOT_PACKET | MIPI_DSI_MODE_VIDEO_BURST;
- ret = s6e63m0_probe(dev, s6e63m0_dsi_dcs_write, true); + ret = s6e63m0_probe(dev, s6e63m0_dsi_dcs_read, s6e63m0_dsi_dcs_write, + true); if (ret) return ret;
diff --git a/drivers/gpu/drm/panel/panel-samsung-s6e63m0-spi.c b/drivers/gpu/drm/panel/panel-samsung-s6e63m0-spi.c index 0587eac52f2a..3b1a2a3a44ea 100644 --- a/drivers/gpu/drm/panel/panel-samsung-s6e63m0-spi.c +++ b/drivers/gpu/drm/panel/panel-samsung-s6e63m0-spi.c @@ -11,6 +11,17 @@
#define DATA_MASK 0x100
+static int s6e63m0_spi_dcs_read(struct device *dev, const u8 cmd, u8 *data) +{ + /* + * FIXME: implement reading DCS commands over SPI so we can + * properly identify which physical panel is connected. + */ + *data = 0; + + return 0; +} + static int s6e63m0_spi_write_word(struct device *dev, u16 data) { struct spi_device *spi = to_spi_device(dev); @@ -60,7 +71,8 @@ static int s6e63m0_spi_probe(struct spi_device *spi) DRM_DEV_ERROR(dev, "spi setup failed.\n"); return ret; } - return s6e63m0_probe(dev, s6e63m0_spi_dcs_write, false); + return s6e63m0_probe(dev, s6e63m0_spi_dcs_read, s6e63m0_spi_dcs_write, + false); }
static int s6e63m0_spi_remove(struct spi_device *spi) diff --git a/drivers/gpu/drm/panel/panel-samsung-s6e63m0.c b/drivers/gpu/drm/panel/panel-samsung-s6e63m0.c index c6d17e938955..b25021bdd724 100644 --- a/drivers/gpu/drm/panel/panel-samsung-s6e63m0.c +++ b/drivers/gpu/drm/panel/panel-samsung-s6e63m0.c @@ -87,6 +87,7 @@ static u8 const s6e63m0_gamma_22[NUM_GAMMA_LEVELS][GAMMA_TABLE_COUNT] = {
struct s6e63m0 { struct device *dev; + int (*dcs_read)(struct device *dev, const u8 cmd, u8 *val); int (*dcs_write)(struct device *dev, const u8 *data, size_t len); struct drm_panel panel; struct backlight_device *bl_dev; @@ -136,6 +137,14 @@ static int s6e63m0_clear_error(struct s6e63m0 *ctx) return ret; }
+static void s6e63m0_dcs_read(struct s6e63m0 *ctx, const u8 cmd, u8 *data) +{ + if (ctx->error < 0) + return; + + ctx->error = ctx->dcs_read(ctx->dev, cmd, data); +} + static void s6e63m0_dcs_write(struct s6e63m0 *ctx, const u8 *data, size_t len) { if (ctx->error < 0 || len == 0) @@ -403,6 +412,7 @@ static int s6e63m0_backlight_register(struct s6e63m0 *ctx) }
int s6e63m0_probe(struct device *dev, + int (*dcs_read)(struct device *dev, const u8 cmd, u8 *val), int (*dcs_write)(struct device *dev, const u8 *data, size_t len), bool dsi_mode) { @@ -413,6 +423,7 @@ int s6e63m0_probe(struct device *dev, if (!ctx) return -ENOMEM;
+ ctx->dcs_read = dcs_read; ctx->dcs_write = dcs_write; dev_set_drvdata(dev, ctx);
diff --git a/drivers/gpu/drm/panel/panel-samsung-s6e63m0.h b/drivers/gpu/drm/panel/panel-samsung-s6e63m0.h index 229e23b0c97a..c669fec91763 100644 --- a/drivers/gpu/drm/panel/panel-samsung-s6e63m0.h +++ b/drivers/gpu/drm/panel/panel-samsung-s6e63m0.h @@ -4,6 +4,7 @@ #define _PANEL_SAMSUNG_S6E63M0_H
int s6e63m0_probe(struct device *dev, + int (*dcs_read)(struct device *dev, const u8 cmd, u8 *val), int (*dcs_write)(struct device *dev, const u8 *data, size_t len), bool dsi_mode);