On Fri, Oct 26, 2018 at 9:43 PM Priit Laes [off-list ref] wrote:

On Fri, Oct 26, 2018 at 08:13:39PM +0530, Jagan Teki wrote:

quoted

Techstar TS8550B MIPI DSI panel is 480x854, 2-lane MIPI DSI
LCD panel. Add panel driver for it.

Signed-off-by: Jagan Teki <jagan@amarulasolutions.com>
Tested-by: Jagan Teki <jagan@amarulasolutions.com>
---
Changes for v3:
- new patch
Changes for v2:
- none

 drivers/gpu/drm/panel/Kconfig                 |   9 +
 drivers/gpu/drm/panel/Makefile                |   1 +
 .../gpu/drm/panel/panel-techstar-ts8550b.c    | 346 ++++++++++++++++++
 3 files changed, 356 insertions(+)
 create mode 100644 drivers/gpu/drm/panel/panel-techstar-ts8550b.c

diff --git a/drivers/gpu/drm/panel/Kconfig b/drivers/gpu/drm/panel/Kconfig
index 20b88c275421..d0d4e60f5153 100644
--- a/drivers/gpu/drm/panel/Kconfig
+++ b/drivers/gpu/drm/panel/Kconfig

@@ -195,4 +195,13 @@ config DRM_PANEL_SITRONIX_ST7789V
        Say Y here if you want to enable support for the Sitronix
        ST7789V controller for 240x320 LCD panels

+config DRM_PANEL_TECHSTAR_TS8550B
+     tristate "Techstar TS8550B MIPI-DSI panel driver"
+     depends on OF
+     depends on DRM_MIPI_DSI
+     depends on BACKLIGHT_CLASS_DEVICE
+     help
+       Say Y if you want to enable support for panels based on the
+       Techstar TS8550B MIPI-DSI interface.
+
 endmenu

diff --git a/drivers/gpu/drm/panel/Makefile b/drivers/gpu/drm/panel/Makefile
index 04696bb85218..88011f06edb8 100644
--- a/drivers/gpu/drm/panel/Makefile
+++ b/drivers/gpu/drm/panel/Makefile

@@ -20,3 +20,4 @@ obj-$(CONFIG_DRM_PANEL_SEIKO_43WVF1G) += panel-seiko-43wvf1g.o
 obj-$(CONFIG_DRM_PANEL_SHARP_LQ101R1SX01) += panel-sharp-lq101r1sx01.o
 obj-$(CONFIG_DRM_PANEL_SHARP_LS043T1LE01) += panel-sharp-ls043t1le01.o
 obj-$(CONFIG_DRM_PANEL_SITRONIX_ST7789V) += panel-sitronix-st7789v.o
+obj-$(CONFIG_DRM_PANEL_TECHSTAR_TS8550B) += panel-techstar-ts8550b.o

diff --git a/drivers/gpu/drm/panel/panel-techstar-ts8550b.c b/drivers/gpu/drm/panel/panel-techstar-ts8550b.c
new file mode 100644
index 000000000000..8baca71595a7
--- /dev/null
+++ b/drivers/gpu/drm/panel/panel-techstar-ts8550b.c

@@ -0,0 +1,346 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (C) 2019, Amarula Solutions.
+ * Author: Jagan Teki <jagan@amarulasolutions.com>
+ */
+
+#include <linux/backlight.h>
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/err.h>
+#include <linux/errno.h>
+#include <linux/fb.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+
+#include <linux/gpio/consumer.h>
+#include <linux/regulator/consumer.h>
+
+#include <drm/drm_mipi_dsi.h>
+#include <drm/drm_modes.h>
+#include <drm/drm_panel.h>
+
+#include <video/mipi_display.h>
+
+struct ts8550b {
+     struct drm_panel        panel;
+     struct mipi_dsi_device  *dsi;
+
+     struct backlight_device *backlight;
+     struct regulator        *dvdd;
+     struct regulator        *avdd;
+     struct gpio_desc        *reset;
+
+     bool                    is_enabled;
+     bool                    is_prepared;
+};
+
+static inline struct ts8550b *panel_to_ts8550b(struct drm_panel *panel)
+{
+     return container_of(panel, struct ts8550b, panel);
+}
+
+static inline int ts8550b_dcs_write_seq(struct ts8550b *ctx, const void *seq,
+                                     size_t len)
+{
+     return mipi_dsi_dcs_write_buffer(ctx->dsi, seq, len);
+};
+
+#define ts8550b_dcs_write_seq_static(ctx, seq...)            \
+     ({                                                      \
+             static const u8 d[] = { seq };                  \
+             ts8550b_dcs_write_seq(ctx, d, ARRAY_SIZE(d));   \
+     })
+
+static void ts8550b_init_sequence(struct ts8550b *ctx)

This seems to be pretty "standard" MIPI-based display, utilizing
bunch of manufacturer-specific commands during init sequence.

Standard MIPI commands fall between 0x00..0xAF and are defined in <video/mipi.h>

Where is this file? we have include/video/mipi_display.h with
0x00..0xA8. Not all commands in sequence is listed in this, may be I
will update DCS commands macros and rest as-it-is. what do you think?