diff mbox series

[v10,2/2] drm: exynos: dsi: Properly name HSA/HBP/HFP/HSE bits

Message ID 20221212145745.15387-2-jagan@amarulasolutions.com (mailing list archive)
State New, archived
Headers show
Series [v10,1/2] drm: exynos: dsi: Fix MIPI_DSI*_NO_* mode flags | expand

Commit Message

Jagan Teki Dec. 12, 2022, 2:57 p.m. UTC 
HSA/HBP/HFP/HSE mode bits in Processor Reference Manuals specify
a naming conversion as 'disable mode bit' due to its bit definition,
0 = Enable and 1 = Disable.

For HSE bit, the i.MX 8M Mini/Nano/Plus Applications Processor
Reference Manual named this bit as 'HseDisableMode' but the bit
definition is quite opposite like
0 = Disables transfer
1 = Enables transfer
which clearly states that HSE is not a disable bit.

HSE is named as per the manual even though it is not a disable
bit however the driver logic for handling HSE is based on the
MIPI_DSI_MODE_VIDEO_HSE flag itself.

Cc: Nicolas Boichat <drinkcat@chromium.org>
Reviewed-by: Marek Vasut <marex@denx.de>
Signed-off-by: Jagan Teki <jagan@amarulasolutions.com>
---
Changes for v10:
- add Marek V review tag
Changes for v9:
- new patch

 drivers/gpu/drm/exynos/exynos_drm_dsi.c | 33 +++++++++++++++++++------
 1 file changed, 25 insertions(+), 8 deletions(-)

Comments

Frieder Schrempf Dec. 14, 2022, 9:02 a.m. UTC | #1 
On 12.12.22 15:57, Jagan Teki wrote:
> HSA/HBP/HFP/HSE mode bits in Processor Reference Manuals specify
> a naming conversion as 'disable mode bit' due to its bit definition,
> 0 = Enable and 1 = Disable.
> 
> For HSE bit, the i.MX 8M Mini/Nano/Plus Applications Processor
> Reference Manual named this bit as 'HseDisableMode' but the bit
> definition is quite opposite like
> 0 = Disables transfer
> 1 = Enables transfer
> which clearly states that HSE is not a disable bit.
> 
> HSE is named as per the manual even though it is not a disable
> bit however the driver logic for handling HSE is based on the
> MIPI_DSI_MODE_VIDEO_HSE flag itself.
> 
> Cc: Nicolas Boichat <drinkcat@chromium.org>
> Reviewed-by: Marek Vasut <marex@denx.de>
> Signed-off-by: Jagan Teki <jagan@amarulasolutions.com>

Reviewed-by: Frieder Schrempf <frieder.schrempf@kontron.de>
diff mbox series

Patch

diff --git a/drivers/gpu/drm/exynos/exynos_drm_dsi.c b/drivers/gpu/drm/exynos/exynos_drm_dsi.c
index 50a2a9ca88a9..b64bb6006b7d 100644
--- a/drivers/gpu/drm/exynos/exynos_drm_dsi.c
+++ b/drivers/gpu/drm/exynos/exynos_drm_dsi.c
@@ -75,10 +75,27 @@ 
 #define DSIM_MAIN_PIX_FORMAT_RGB565	(0x4 << 12)
 #define DSIM_SUB_VC			(((x) & 0x3) << 16)
 #define DSIM_MAIN_VC			(((x) & 0x3) << 18)
-#define DSIM_HSA_MODE			(1 << 20)
-#define DSIM_HBP_MODE			(1 << 21)
-#define DSIM_HFP_MODE			(1 << 22)
-#define DSIM_HSE_MODE			(1 << 23)
+#define DSIM_HSA_DISABLE_MODE		(1 << 20)
+#define DSIM_HBP_DISABLE_MODE		(1 << 21)
+#define DSIM_HFP_DISABLE_MODE		(1 << 22)
+/*
+ * The i.MX 8M Mini Applications Processor Reference Manual,
+ * Rev. 3, 11/2020 Page 4091
+ * The i.MX 8M Nano Applications Processor Reference Manual,
+ * Rev. 2, 07/2022 Page 3058
+ * The i.MX 8M Plus Applications Processor Reference Manual,
+ * Rev. 1, 06/2021 Page 5436
+ * named this bit as 'HseDisableMode' but the bit definition
+ * is quite opposite like
+ * 0 = Disables transfer
+ * 1 = Enables transfer
+ * which clearly states that HSE is not a disable bit.
+ *
+ * This bit is named as per the manual even though it is not
+ * a disable bit however the driver logic for handling HSE
+ * is based on the MIPI_DSI_MODE_VIDEO_HSE flag itself.
+ */
+#define DSIM_HSE_DISABLE_MODE		(1 << 23)
 #define DSIM_AUTO_MODE			(1 << 24)
 #define DSIM_VIDEO_MODE			(1 << 25)
 #define DSIM_BURST_MODE			(1 << 26)
@@ -804,13 +821,13 @@  static int exynos_dsi_init_link(struct exynos_dsi *dsi)
 		if (dsi->mode_flags & MIPI_DSI_MODE_VIDEO_AUTO_VERT)
 			reg |= DSIM_AUTO_MODE;
 		if (dsi->mode_flags & MIPI_DSI_MODE_VIDEO_HSE)
-			reg |= DSIM_HSE_MODE;
+			reg |= DSIM_HSE_DISABLE_MODE;
 		if (dsi->mode_flags & MIPI_DSI_MODE_VIDEO_NO_HFP)
-			reg |= DSIM_HFP_MODE;
+			reg |= DSIM_HFP_DISABLE_MODE;
 		if (dsi->mode_flags & MIPI_DSI_MODE_VIDEO_NO_HBP)
-			reg |= DSIM_HBP_MODE;
+			reg |= DSIM_HBP_DISABLE_MODE;
 		if (dsi->mode_flags & MIPI_DSI_MODE_VIDEO_NO_HSA)
-			reg |= DSIM_HSA_MODE;
+			reg |= DSIM_HSA_DISABLE_MODE;
 	}
 
 	if (dsi->mode_flags & MIPI_DSI_MODE_NO_EOT_PACKET)