[PATCH 4/8] drm/tidss: Add support for Dual Link LVDS Bus Format

From: Aradhya Bhatia
Date: Tue Jul 19 2022 - 04:09:36 EST


The 2 OLDI TXes in the AM625 SoC can be synced together to output a 2K
resolution video.

Add support in the driver for the discovery of such a dual mode
connection on the OLDI video port, using the values of "ti,oldi-mode"
property.

Signed-off-by: Aradhya Bhatia <a-bhatia1@xxxxxx>
---
drivers/gpu/drm/tidss/tidss_dispc.c | 39 +++++++++++++++++++++--------
1 file changed, 28 insertions(+), 11 deletions(-)

diff --git a/drivers/gpu/drm/tidss/tidss_dispc.c b/drivers/gpu/drm/tidss/tidss_dispc.c
index add725fa682b..fb1fdecfc83a 100644
--- a/drivers/gpu/drm/tidss/tidss_dispc.c
+++ b/drivers/gpu/drm/tidss/tidss_dispc.c
@@ -853,25 +853,36 @@ void dispc_set_irqenable(struct dispc_device *dispc, dispc_irq_t mask)
}
}

-enum dispc_oldi_mode_reg_val { SPWG_18 = 0, JEIDA_24 = 1, SPWG_24 = 2 };
+enum dispc_oldi_mode_reg_val {
+ SPWG_18 = 0,
+ JEIDA_24 = 1,
+ SPWG_24 = 2,
+ DL_SPWG_18 = 4,
+ DL_JEIDA_24 = 5,
+ DL_SPWG_24 = 6,
+};

struct dispc_bus_format {
u32 bus_fmt;
u32 data_width;
bool is_oldi_fmt;
+ bool is_dual_link;
enum dispc_oldi_mode_reg_val oldi_mode_reg_val;
};

static const struct dispc_bus_format dispc_bus_formats[] = {
- { MEDIA_BUS_FMT_RGB444_1X12, 12, false, 0 },
- { MEDIA_BUS_FMT_RGB565_1X16, 16, false, 0 },
- { MEDIA_BUS_FMT_RGB666_1X18, 18, false, 0 },
- { MEDIA_BUS_FMT_RGB888_1X24, 24, false, 0 },
- { MEDIA_BUS_FMT_RGB101010_1X30, 30, false, 0 },
- { MEDIA_BUS_FMT_RGB121212_1X36, 36, false, 0 },
- { MEDIA_BUS_FMT_RGB666_1X7X3_SPWG, 18, true, SPWG_18 },
- { MEDIA_BUS_FMT_RGB888_1X7X4_SPWG, 24, true, SPWG_24 },
- { MEDIA_BUS_FMT_RGB888_1X7X4_JEIDA, 24, true, JEIDA_24 },
+ { MEDIA_BUS_FMT_RGB444_1X12, 12, false, false, 0 },
+ { MEDIA_BUS_FMT_RGB565_1X16, 16, false, false, 0 },
+ { MEDIA_BUS_FMT_RGB666_1X18, 18, false, false, 0 },
+ { MEDIA_BUS_FMT_RGB888_1X24, 24, false, false, 0 },
+ { MEDIA_BUS_FMT_RGB101010_1X30, 30, false, false, 0 },
+ { MEDIA_BUS_FMT_RGB121212_1X36, 36, false, false, 0 },
+ { MEDIA_BUS_FMT_RGB666_1X7X3_SPWG, 18, true, false, SPWG_18 },
+ { MEDIA_BUS_FMT_RGB888_1X7X4_SPWG, 24, true, false, SPWG_24 },
+ { MEDIA_BUS_FMT_RGB888_1X7X4_JEIDA, 24, true, false, JEIDA_24 },
+ { MEDIA_BUS_FMT_RGB666_1X7X3_SPWG, 18, true, true, DL_SPWG_18 },
+ { MEDIA_BUS_FMT_RGB888_1X7X4_SPWG, 24, true, true, DL_SPWG_24 },
+ { MEDIA_BUS_FMT_RGB888_1X7X4_JEIDA, 24, true, true, DL_JEIDA_24 },
};

static const
@@ -880,9 +891,15 @@ struct dispc_bus_format *dispc_vp_find_bus_fmt(struct dispc_device *dispc,
u32 bus_fmt, u32 bus_flags)
{
unsigned int i;
+ bool is_dual_link = false;
+
+ if (dispc->feat->vp_bus_type[hw_videoport] == DISPC_VP_OLDI &&
+ dispc->oldi_mode == OLDI_DUAL_LINK)
+ is_dual_link = true;

for (i = 0; i < ARRAY_SIZE(dispc_bus_formats); ++i) {
- if (dispc_bus_formats[i].bus_fmt == bus_fmt)
+ if (dispc_bus_formats[i].bus_fmt == bus_fmt &&
+ dispc_bus_formats[i].is_dual_link == is_dual_link)
return &dispc_bus_formats[i];
}

--
2.37.0