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

Stephan Gerhold stephan at gerhold.net
Fri Aug 14 15:34:19 UTC 2020


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 at gerhold.net>
> Cc: Paweł Chmiel <pawel.mikolaj.chmiel at gmail.com>
> Signed-off-by: Linus Walleij <linus.walleij at 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 at 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 at 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
> 


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