Re: [PATCH 2/4] drm/panel: s6e63m0: Add DSI transport

On Sun, Aug 09, 2020 at 11:51:02PM +0200, Linus Walleij wrote:

This makes it possible to use the s6e63m0 panel with a DSI host, such as in the Samsung GT-I8190 (Golden) mobile phone.

Cc: Stephan Gerhold stephan@gerhold.net Cc: Paweł Chmiel pawel.mikolaj.chmiel@gmail.com Signed-off-by: Linus Walleij linus.walleij@linaro.org

---

drivers/gpu/drm/panel/Kconfig | 8 ++ drivers/gpu/drm/panel/Makefile | 1 + .../gpu/drm/panel/panel-samsung-s6e63m0-dsi.c | 128 ++++++++++++++++++ .../gpu/drm/panel/panel-samsung-s6e63m0-spi.c | 2 +- drivers/gpu/drm/panel/panel-samsung-s6e63m0.c | 4 +- drivers/gpu/drm/panel/panel-samsung-s6e63m0.h | 4 +- 6 files changed, 144 insertions(+), 3 deletions(-) create mode 100644 drivers/gpu/drm/panel/panel-samsung-s6e63m0-dsi.c

diff --git a/drivers/gpu/drm/panel/Kconfig b/drivers/gpu/drm/panel/Kconfig index 96e1548e475f..731e84c5a13b 100644 --- a/drivers/gpu/drm/panel/Kconfig +++ b/drivers/gpu/drm/panel/Kconfig @@ -343,6 +343,14 @@ config DRM_PANEL_SAMSUNG_S6E63M0_SPI Say Y here if you want to be able to access the Samsung S6E63M0 panel using SPI.

+config DRM_PANEL_SAMSUNG_S6E63M0_DSI

• tristate "Samsung S6E63M0 RGB DSI interface"
• depends on DRM_MIPI_DSI
• depends on DRM_PANEL_SAMSUNG_S6E63M0
• help

•  Say Y here if you want to be able to access the Samsung
  

•  S6E63M0 panel using DSI.
  

config DRM_PANEL_SAMSUNG_S6E88A0_AMS452EF01 tristate "Samsung AMS452EF01 panel with S6E88A0 DSI video mode controller" depends on OF diff --git a/drivers/gpu/drm/panel/Makefile b/drivers/gpu/drm/panel/Makefile index 9cf71adfa794..14212cae3c29 100644 --- a/drivers/gpu/drm/panel/Makefile +++ b/drivers/gpu/drm/panel/Makefile @@ -35,6 +35,7 @@ obj-$(CONFIG_DRM_PANEL_SAMSUNG_S6E3HA2) += panel-samsung-s6e3ha2.o obj-$(CONFIG_DRM_PANEL_SAMSUNG_S6E63J0X03) += panel-samsung-s6e63j0x03.o obj-$(CONFIG_DRM_PANEL_SAMSUNG_S6E63M0) += panel-samsung-s6e63m0.o obj-$(CONFIG_DRM_PANEL_SAMSUNG_S6E63M0_SPI) += panel-samsung-s6e63m0-spi.o +obj-$(CONFIG_DRM_PANEL_SAMSUNG_S6E63M0_DSI) += panel-samsung-s6e63m0-dsi.o obj-$(CONFIG_DRM_PANEL_SAMSUNG_S6E88A0_AMS452EF01) += panel-samsung-s6e88a0-ams452ef01.o obj-$(CONFIG_DRM_PANEL_SAMSUNG_S6E8AA0) += panel-samsung-s6e8aa0.o obj-$(CONFIG_DRM_PANEL_SEIKO_43WVF1G) += panel-seiko-43wvf1g.o diff --git a/drivers/gpu/drm/panel/panel-samsung-s6e63m0-dsi.c b/drivers/gpu/drm/panel/panel-samsung-s6e63m0-dsi.c new file mode 100644 index 000000000000..f4927a6ce26d --- /dev/null +++ b/drivers/gpu/drm/panel/panel-samsung-s6e63m0-dsi.c @@ -0,0 +1,128 @@ +// SPDX-License-Identifier: GPL-2.0 +/*

• • DSI interface to the Samsung S6E63M0 panel.
• • (C) 2019 Linus Walleij
• */

+#include <linux/module.h> +#include <linux/delay.h> +#include <linux/of_device.h>

+#include <drm/drm_mipi_dsi.h> +#include <drm/drm_print.h>

+#include "panel-samsung-s6e63m0.h"

+#define MCS_GLOBAL_PARAM 0xb0 +#define S6E63M0_DSI_MAX_CHUNK 15 /* CMD + 15 bytes max */

+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);
• const u8 *seqp = data;
• u8 cmd;
• u8 cmdwritten;
• int remain;
• int chunk;
• int ret;
• DRM_DEV_INFO(dev, "DSI writing dcs seq: %*ph\n", (int)len, data);

We should probably remove these or demote them to debug. It's quite verbose.

• /* Pick out and skip past the DCS command */
• cmd = *seqp;
• seqp++;
• cmdwritten = 0;
• remain = len - 1;
• chunk = remain;
• /* Send max S6E63M0_DSI_MAX_CHUNK bytes at a time */
• if (chunk > S6E63M0_DSI_MAX_CHUNK)

• chunk = S6E63M0_DSI_MAX_CHUNK;
  

• ret = mipi_dsi_dcs_write(dsi, cmd, seqp, chunk);
• if (ret < 0) {

• DRM_DEV_ERROR(dev,
  

• 	      "error sending DCS command seq cmd %02x\n",
  

• 	      cmd);
  

• return ret;
  

• }
• cmdwritten += chunk;
• seqp += chunk;
• while (cmdwritten < remain) {

• chunk = remain - cmdwritten;
  

• if (chunk > S6E63M0_DSI_MAX_CHUNK)
  

• 	chunk = S6E63M0_DSI_MAX_CHUNK;
  

• ret = mipi_dsi_dcs_write(dsi, MCS_GLOBAL_PARAM, &cmdwritten, 1);
  

• if (ret < 0) {
  

• 	DRM_DEV_ERROR(dev,
  

• 		      "error sending CMD %02x global param %02x\n",
  

• 		      cmd, cmdwritten);
  

• 	return ret;
  

• }
  

• ret = mipi_dsi_dcs_write(dsi, cmd, seqp, chunk);
  

• if (ret < 0) {
  

• 	DRM_DEV_ERROR(dev,
  

• 		      "error sending CMD %02x chunk\n",
  

• 		      cmd);
  

• 	return ret;
  

• }
  

• cmdwritten += chunk;
  

• seqp += chunk;
  

• }
• DRM_DEV_INFO(dev, "sent command %02x %02x bytes\n",

•      cmd, cmdwritten);
  

Here as well.

However, otherwise it seems to work fine on my samsung-golden, so for the entire series:

Tested-by: Stephan Gerhold stephan@gerhold.net

I think it would be great to get a Tested-by from someone using the SPI transport as well. It seems to be used in s5pv210-aries.dtsi.

Thanks! Stephan

• usleep_range(8000, 9000);
• return 0;

+}

+static int s6e63m0_dsi_probe(struct mipi_dsi_device *dsi) +{

• struct device *dev = &dsi->dev;
• int ret;
• dsi->lanes = 2;
• dsi->format = MIPI_DSI_FMT_RGB888;
• dsi->hs_rate = 349440000;
• dsi->lp_rate = 9600000;
• dsi->mode_flags = MIPI_DSI_MODE_VIDEO |

• MIPI_DSI_MODE_EOT_PACKET |
  

• MIPI_DSI_MODE_VIDEO_BURST;
  

• ret = s6e63m0_probe(dev, s6e63m0_dsi_dcs_write, true);
• if (ret)

• return ret;
  

• ret = mipi_dsi_attach(dsi);
• if (ret < 0)

• s6e63m0_remove(dev);
  

• return ret;

+}

+static int s6e63m0_dsi_remove(struct mipi_dsi_device *dsi) +{

• mipi_dsi_detach(dsi);
• return s6e63m0_remove(&dsi->dev);

+}

+static const struct of_device_id s6e63m0_dsi_of_match[] = {

• { .compatible = "samsung,s6e63m0" },
• { /* sentinel */ }

+}; +MODULE_DEVICE_TABLE(of, s6e63m0_dsi_of_match);

+static struct mipi_dsi_driver s6e63m0_dsi_driver = {

• .probe = s6e63m0_dsi_probe,
• .remove = s6e63m0_dsi_remove,
• .driver = {

• .name		= "panel-samsung-s6e63m0",
  

• .of_match_table = s6e63m0_dsi_of_match,
  

• },

+}; +module_mipi_dsi_driver(s6e63m0_dsi_driver);

+MODULE_AUTHOR("Linus Walleij linusw@kernel.org"); +MODULE_DESCRIPTION("s6e63m0 LCD DSI Driver"); +MODULE_LICENSE("GPL v2"); diff --git a/drivers/gpu/drm/panel/panel-samsung-s6e63m0-spi.c b/drivers/gpu/drm/panel/panel-samsung-s6e63m0-spi.c index 4082fbd75b79..0587eac52f2a 100644 --- a/drivers/gpu/drm/panel/panel-samsung-s6e63m0-spi.c +++ b/drivers/gpu/drm/panel/panel-samsung-s6e63m0-spi.c @@ -60,7 +60,7 @@ 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);

• return s6e63m0_probe(dev, 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 610676ef8a75..c6d17e938955 100644 --- a/drivers/gpu/drm/panel/panel-samsung-s6e63m0.c +++ b/drivers/gpu/drm/panel/panel-samsung-s6e63m0.c @@ -403,7 +403,8 @@ static int s6e63m0_backlight_register(struct s6e63m0 *ctx) }

int s6e63m0_probe(struct device *dev,

•   int (*dcs_write)(struct device *dev, const u8 *data, size_t len))
  

•   int (*dcs_write)(struct device *dev, const u8 *data, size_t len),
  

•   bool dsi_mode)
  

{ struct s6e63m0 *ctx; int ret; @@ -436,6 +437,7 @@ int s6e63m0_probe(struct device *dev, }

drm_panel_init(&ctx->panel, dev, &s6e63m0_drm_funcs,

•        dsi_mode ? DRM_MODE_CONNECTOR_DSI :
    DRM_MODE_CONNECTOR_DPI);
  
  

  ret = s6e63m0_backlight_register(ctx);

diff --git a/drivers/gpu/drm/panel/panel-samsung-s6e63m0.h b/drivers/gpu/drm/panel/panel-samsung-s6e63m0.h index 44e31f39f211..229e23b0c97a 100644 --- a/drivers/gpu/drm/panel/panel-samsung-s6e63m0.h +++ b/drivers/gpu/drm/panel/panel-samsung-s6e63m0.h @@ -4,7 +4,9 @@ #define _PANEL_SAMSUNG_S6E63M0_H

int s6e63m0_probe(struct device *dev,

•   int (*dcs_write)(struct device *dev, const u8 *data, size_t len));
  

•   int (*dcs_write)(struct device *dev, const u8 *data,
  

• 		   size_t len),
  

•   bool dsi_mode);
  

int s6e63m0_remove(struct device *dev);

#endif /* _PANEL_SAMSUNG_S6E63M0_H */

2.26.2