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Message-ID: <3cca2809-fa26-f0cf-2ccc-6737d150b43d@linaro.org>
Date:   Thu, 18 May 2023 03:19:49 +0300
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Subject: Re: [PATCH 2/2] drm/panel: Add driver for Visionox r66451 panel
Content-Language: en-GB
To:     Jessica Zhang <quic_jesszhan@quicinc.com>,
        Neil Armstrong <neil.armstrong@linaro.org>,
        Sam Ravnborg <sam@ravnborg.org>,
        David Airlie <airlied@gmail.com>,
        Daniel Vetter <daniel@ffwll.ch>,
        Rob Herring <robh+dt@kernel.org>,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>
Cc:     Abhinav Kumar <quic_abhinavk@quicinc.com>,
        dri-devel@lists.freedesktop.org, devicetree@vger.kernel.org,
        linux-kernel@vger.kernel.org
References: <20230516-b4-r66451-panel-driver-v1-0-4210bcbb1649@quicinc.com>
 <20230516-b4-r66451-panel-driver-v1-2-4210bcbb1649@quicinc.com>
From:   Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
In-Reply-To: <20230516-b4-r66451-panel-driver-v1-2-4210bcbb1649@quicinc.com>
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On 16/05/2023 23:20, Jessica Zhang wrote:
> Add support for the 1080x2340 Visionox R66451 AMOLED DSI panel that
> comes with the Qualcomm HDK8350 display expansion pack.
> 
> The panel enables display compression (DSC v1.2) by default.
> 
> Signed-off-by: Jessica Zhang <quic_jesszhan@quicinc.com>
> ---
>   drivers/gpu/drm/panel/Kconfig                 |   8 +
>   drivers/gpu/drm/panel/Makefile                |   1 +
>   drivers/gpu/drm/panel/panel-visionox-r66451.c | 395 ++++++++++++++++++++++++++
>   3 files changed, 404 insertions(+)
> 
> diff --git a/drivers/gpu/drm/panel/Kconfig b/drivers/gpu/drm/panel/Kconfig
> index 29cf5fa39ff2..9c2c36dbddf3 100644
> --- a/drivers/gpu/drm/panel/Kconfig
> +++ b/drivers/gpu/drm/panel/Kconfig
> @@ -766,6 +766,14 @@ config DRM_PANEL_VISIONOX_VTDR6130
>   	  Say Y here if you want to enable support for Visionox
>   	  VTDR6130 1080x2400 AMOLED DSI panel.
>   
> +config DRM_PANEL_VISIONOX_R66451
> +	tristate "Visionox R66451"
> +	depends on OF
> +	depends on DRM_MIPI_DSI
> +	help
> +	  Say Y here if you want to enable support for Visionox
> +	  R66451 1080x2340 AMOLED DSI panel.
> +
>   config DRM_PANEL_WIDECHIPS_WS2401
>   	tristate "Widechips WS2401 DPI panel driver"
>   	depends on SPI && GPIOLIB
> diff --git a/drivers/gpu/drm/panel/Makefile b/drivers/gpu/drm/panel/Makefile
> index b3e8ba29edd3..e043a92ee676 100644
> --- a/drivers/gpu/drm/panel/Makefile
> +++ b/drivers/gpu/drm/panel/Makefile
> @@ -78,5 +78,6 @@ obj-$(CONFIG_DRM_PANEL_TPO_TPG110) += panel-tpo-tpg110.o
>   obj-$(CONFIG_DRM_PANEL_TRULY_NT35597_WQXGA) += panel-truly-nt35597.o
>   obj-$(CONFIG_DRM_PANEL_VISIONOX_RM69299) += panel-visionox-rm69299.o
>   obj-$(CONFIG_DRM_PANEL_VISIONOX_VTDR6130) += panel-visionox-vtdr6130.o
> +obj-$(CONFIG_DRM_PANEL_VISIONOX_R66451) += panel-visionox-r66451.o
>   obj-$(CONFIG_DRM_PANEL_WIDECHIPS_WS2401) += panel-widechips-ws2401.o
>   obj-$(CONFIG_DRM_PANEL_XINPENG_XPP055C272) += panel-xinpeng-xpp055c272.o
> diff --git a/drivers/gpu/drm/panel/panel-visionox-r66451.c b/drivers/gpu/drm/panel/panel-visionox-r66451.c
> new file mode 100644
> index 000000000000..e3648ead3e84
> --- /dev/null
> +++ b/drivers/gpu/drm/panel/panel-visionox-r66451.c
> @@ -0,0 +1,395 @@
> +//SPDX-License-Identifier: GPL-2.0-only
> +//Copyright (c) 2023 Qualcomm Innovation Center, Inc. All rights reserved.
> +
> +#include <linux/backlight.h>
> +#include <linux/delay.h>
> +#include <linux/gpio/consumer.h>
> +#include <linux/module.h>
> +#include <linux/of.h>
> +#include <linux/regulator/consumer.h>
> +
> +#include <drm/drm_mipi_dsi.h>
> +#include <drm/drm_modes.h>
> +#include <drm/drm_panel.h>
> +#include <drm/display/drm_dsc.h>
> +#include <drm/display/drm_dsc_helper.h>
> +
> +#include <video/mipi_display.h>
> +
> +struct visionox_r66451 {
> +	struct drm_panel panel;
> +	struct mipi_dsi_device *dsi;
> +	struct gpio_desc *reset_gpio;
> +	struct regulator_bulk_data supplies[2];
> +	bool prepared, enabled;
> +};
> +
> +static inline struct visionox_r66451 *to_visionox_r66451(struct drm_panel *panel)
> +{
> +	return container_of(panel, struct visionox_r66451, panel);
> +}
> +
> +static void visionox_r66451_reset(struct visionox_r66451 *ctx)
> +{
> +	gpiod_set_value_cansleep(ctx->reset_gpio, 0);
> +	usleep_range(10000, 10100);
> +	gpiod_set_value_cansleep(ctx->reset_gpio, 1);
> +	usleep_range(10000, 10100);
> +	gpiod_set_value_cansleep(ctx->reset_gpio, 0);
> +	usleep_range(10000, 10100);
> +}
> +
> +static int visionox_r66451_on(struct visionox_r66451 *ctx)
> +{
> +	struct mipi_dsi_device *dsi = ctx->dsi;
> +	struct device *dev = &dsi->dev;
> +	int ret;
> +
> +	dsi->mode_flags |= MIPI_DSI_MODE_LPM;
> +
> +	mipi_dsi_dcs_write_seq(dsi, 0xb0, 0x00);
> +	mipi_dsi_dcs_write_seq(dsi, 0xc2,
> +			       0x09, 0x24, 0x0c, 0x00, 0x00, 0x0c, 0x00, 0x00, 0x00,
> +			       0x09, 0x3c);
> +	mipi_dsi_dcs_write_seq(dsi, 0xd7,
> +			       0x00, 0xb9, 0x3c, 0x00, 0x40, 0x04, 0x00, 0xa0, 0x0a,
> +			       0x00, 0x40, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x19,
> +			       0x3c, 0x00, 0x40, 0x04, 0x00, 0xa0, 0x0a);
> +	mipi_dsi_dcs_write_seq(dsi, 0xb0, 0x80);
> +	mipi_dsi_dcs_write_seq(dsi, 0xde,
> +			       0x40, 0x00, 0x18, 0x00, 0x18, 0x00, 0x18, 0x00, 0x18,
> +			       0x10, 0x00, 0x18, 0x00, 0x18, 0x00, 0x18, 0x02, 0x00, 0x00);
> +	mipi_dsi_dcs_write_seq(dsi, 0xb0, 0x04);
> +	mipi_dsi_dcs_write_seq(dsi, 0xe8, 0x00, 0x02);
> +	mipi_dsi_dcs_write_seq(dsi, 0xe4, 0x00, 0x08);
> +	mipi_dsi_dcs_write_seq(dsi, 0xb0, 0x00);
> +	mipi_dsi_dcs_write_seq(dsi, 0xc4,
> +			       0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
> +			       0x00, 0x00, 0x02, 0x00, 0x00, 0x00, 0x32);
> +	mipi_dsi_dcs_write_seq(dsi, 0xcf,
> +			       0x64, 0x0b, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x08,
> +			       0x00, 0x0b, 0x77, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01,
> +			       0x02, 0x02, 0x02, 0x02, 0x02, 0x03);
> +	mipi_dsi_dcs_write_seq(dsi, 0xd3,
> +			       0x45, 0x00, 0x00, 0x01, 0x13, 0x15, 0x00, 0x15, 0x07,
> +			       0x0f, 0x77, 0x77, 0x77, 0x37, 0xb2, 0x11, 0x00, 0xa0,
> +			       0x3c, 0x9c);
> +	mipi_dsi_dcs_write_seq(dsi, 0xd7,
> +			       0x00, 0xb9, 0x34, 0x00, 0x40, 0x04, 0x00, 0xa0, 0x0a,
> +			       0x00, 0x40, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x19,
> +			       0x34, 0x00, 0x40, 0x04, 0x00, 0xa0, 0x0a);
> +	mipi_dsi_dcs_write_seq(dsi, 0xd8,
> +			       0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
> +			       0x3a, 0x00, 0x3a, 0x00, 0x3a, 0x00, 0x3a, 0x00, 0x3a,
> +			       0x05, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
> +			       0x00, 0x0a, 0x00, 0x0a, 0x00, 0x00, 0x00, 0x00, 0x00,
> +			       0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x0a,
> +			       0x00, 0x32, 0x00, 0x0a, 0x00, 0x22);
> +	mipi_dsi_dcs_write_seq(dsi, 0xdf,
> +			       0x50, 0x42, 0x58, 0x81, 0x2d, 0x00, 0x00, 0x00, 0x00,
> +			       0x00, 0x00, 0x6b, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
> +			       0x00, 0x00, 0x01, 0x0f, 0xff, 0xd4, 0x0e, 0x00, 0x00,
> +			       0x00, 0x00, 0x00, 0x00, 0x0f, 0x53, 0xf1, 0x00, 0x00,
> +			       0x00, 0x00, 0x00, 0x00, 0x00, 0x00);
> +	mipi_dsi_dcs_write_seq(dsi, 0xf7, 0x01);
> +	mipi_dsi_dcs_write_seq(dsi, 0xb0, 0x80);
> +	mipi_dsi_dcs_write_seq(dsi, 0xe4, 0x34, 0xb4, 0x00, 0x00, 0x00, 0x39, 0x04, 0x09, 0x34);
> +	mipi_dsi_dcs_write_seq(dsi, 0xe6, 0x00);
> +	mipi_dsi_dcs_write_seq(dsi, 0xb0, 0x04);
> +	mipi_dsi_dcs_write_seq(dsi, 0xdf, 0x50, 0x40);
> +	mipi_dsi_dcs_write_seq(dsi, 0xf3, 0x50, 0x00, 0x00, 0x00, 0x00);
> +	mipi_dsi_dcs_write_seq(dsi, 0xf2, 0x11);
> +	mipi_dsi_dcs_write_seq(dsi, 0xf3, 0x01, 0x00, 0x00, 0x00, 0x01);
> +	mipi_dsi_dcs_write_seq(dsi, 0xf4, 0x00, 0x02);
> +	mipi_dsi_dcs_write_seq(dsi, 0xf2, 0x19);
> +	mipi_dsi_dcs_write_seq(dsi, 0xdf, 0x50, 0x42);
> +	mipi_dsi_dcs_set_tear_on(dsi, MIPI_DSI_DCS_TEAR_MODE_VBLANK);
> +	mipi_dsi_dcs_write_seq(dsi, MIPI_DCS_SET_COLUMN_ADDRESS, 0x00, 0x00, 0x04, 0x37);

Please use mipi_dsi_dcs_set_column_address(dsi, 0, 1080 - 1);

> +	mipi_dsi_dcs_write_seq(dsi, MIPI_DCS_SET_PAGE_ADDRESS, 0x00, 0x00, 0x09, 0x23);

mipi_dsi_dcs_set_page_address(dsi, 0, 2340 - 1);

> +
> +	ret = mipi_dsi_dcs_exit_sleep_mode(dsi);
> +	if (ret < 0) {
> +		dev_err(dev, "Failed to exit sleep mode: %d\n", ret);
> +		return ret;
> +	}
> +	msleep(120);
> +
> +	ret = mipi_dsi_dcs_set_display_on(dsi);

Should the mipi_dsi_dcs_set_display_on() (and maybe exit sleep mode) be 
a a part of _enable()? Correspondingly _off should IMO be a part of 
_disable callback().

> +	if (ret < 0) {
> +		dev_err(dev, "Failed on set display on: %d\n", ret);
> +		return ret;
> +	}
> +	msleep(20);


Do we need to add here the following line?

dsi->mode_flags &= ~MIPI_DSI_MODE_LPM;


> +
> +	return 0;
> +}
> +
> +static int visionox_r66451_off(struct visionox_r66451 *ctx)
> +{
> +	struct mipi_dsi_device *dsi = ctx->dsi;
> +	struct device *dev = &dsi->dev;
> +	int ret;
> +
> +	dsi->mode_flags &= ~MIPI_DSI_MODE_LPM;
> +
> +	ret = mipi_dsi_dcs_set_display_off(dsi);
> +	if (ret < 0) {
> +		dev_err(dev, "Failed to set display off: %d\n", ret);
> +		return ret;
> +	}
> +	msleep(20);
> +
> +	ret = mipi_dsi_dcs_enter_sleep_mode(dsi);
> +	if (ret < 0) {
> +		dev_err(dev, "Failed to enter sleep mode: %d\n", ret);
> +		return ret;
> +	}
> +	msleep(120);
> +
> +	return 0;
> +}
> +
> +static int visionox_r66451_prepare(struct drm_panel *panel)
> +{
> +	struct visionox_r66451 *ctx = to_visionox_r66451(panel);
> +	struct device *dev = &ctx->dsi->dev;
> +	int ret;
> +
> +	if (ctx->prepared)
> +		return 0;
> +
> +	ret = regulator_bulk_enable(ARRAY_SIZE(ctx->supplies),
> +				    ctx->supplies);
> +	if (ret < 0)
> +		return ret;
> +
> +	visionox_r66451_reset(ctx);
> +
> +	ret = visionox_r66451_on(ctx);
> +	if (ret < 0) {
> +		dev_err(dev, "Failed to initialize panel: %d\n", ret);
> +		gpiod_set_value_cansleep(ctx->reset_gpio, 1);
> +		regulator_bulk_disable(ARRAY_SIZE(ctx->supplies), ctx->supplies);
> +		return ret;
> +	}
> +
> +	ctx->prepared = true;
> +	return 0;
> +}
> +
> +static int visionox_r66451_unprepare(struct drm_panel *panel)
> +{
> +	struct visionox_r66451 *ctx = to_visionox_r66451(panel);
> +	struct device *dev = &ctx->dsi->dev;
> +	int ret;
> +
> +	if (!ctx->prepared)
> +		return 0;
> +
> +	ret = visionox_r66451_off(ctx);
> +	if (ret < 0)
> +		dev_err(dev, "Failed to un-initialize panel: %d\n", ret);
> +
> +	gpiod_set_value_cansleep(ctx->reset_gpio, 1);
> +	regulator_bulk_disable(ARRAY_SIZE(ctx->supplies), ctx->supplies);
> +
> +	ctx->prepared = false;
> +	return 0;
> +}
> +
> +static const struct drm_display_mode visionox_r66451_mode = {
> +	.clock = (1080 + 95 + 1 + 40) * (2340 + 25 + 1 + 4) * 120 / 1000,
> +	.hdisplay = 1080,
> +	.hsync_start = 1080 + 95,
> +	.hsync_end = 1080 + 95 + 1,
> +	.htotal = 1080 + 95 + 1 + 40,
> +	.vdisplay = 2340,
> +	.vsync_start = 2340 + 25,
> +	.vsync_end = 2340 + 25 + 1,
> +	.vtotal = 2340 + 25 + 1 + 4,
> +	.width_mm = 0,
> +	.height_mm = 0,

Please provide real values here.

> +};
> +
> +static int visionox_r66451_enable(struct drm_panel *panel)
> +{
> +	struct visionox_r66451 *ctx = to_visionox_r66451(panel);
> +	struct mipi_dsi_device *dsi = ctx->dsi;
> +	struct drm_dsc_picture_parameter_set pps;
> +	int ret;
> +
> +	if (ctx->enabled)
> +		return 0;
> +
> +	if (!dsi->dsc) {
> +		dev_err(&dsi->dev, "DSC not attached to DSI\n");
> +		return -ENODEV;
> +	}
> +
> +	drm_dsc_pps_payload_pack(&pps, dsi->dsc);
> +	ret = mipi_dsi_picture_parameter_set(dsi, &pps);
> +
> +	ctx->enabled = true;
> +
> +	return 0;
> +}
> +
> +static int visionox_r66451_disable(struct drm_panel *panel)
> +{
> +	struct visionox_r66451 *ctx = to_visionox_r66451(panel);
> +
> +	ctx->enabled = false;
> +
> +	return 0;
> +}
> +
> +static int visionox_r66451_get_modes(struct drm_panel *panel,
> +				    struct drm_connector *connector)
> +{
> +	struct drm_display_mode *mode;
> +
> +	mode = drm_mode_duplicate(connector->dev, &visionox_r66451_mode);
> +	if (!mode)
> +		return -ENOMEM;
> +
> +	drm_mode_set_name(mode);
> +
> +	mode->type = DRM_MODE_TYPE_DRIVER | DRM_MODE_TYPE_PREFERRED;
> +	connector->display_info.width_mm = mode->width_mm;
> +	connector->display_info.height_mm = mode->height_mm;
> +	drm_mode_probed_add(connector, mode);

Can we use drm_connector_helper_get_modes_fixed() instead?

> +
> +	return 1;
> +}
> +
> +static const struct drm_panel_funcs visionox_r66451_funcs = {
> +	.prepare = visionox_r66451_prepare,
> +	.unprepare = visionox_r66451_unprepare,
> +	.get_modes = visionox_r66451_get_modes,
> +	.enable = visionox_r66451_enable,
> +	.disable = visionox_r66451_disable,
> +};
> +
> +static int visionox_r66451_bl_update_status(struct backlight_device *bl)
> +{
> +	struct mipi_dsi_device *dsi = bl_get_data(bl);
> +	u16 brightness = backlight_get_brightness(bl);
> +
> +	return mipi_dsi_dcs_set_display_brightness(dsi, cpu_to_le16(brightness));

mipi_dsi_dcs_set_display_brightness() already converts the brightness, 
so you don't need cpu_to_le16 here.

> +}
> +
> +static const struct backlight_ops visionox_r66451_bl_ops = {
> +	.update_status = visionox_r66451_bl_update_status,
> +};
> +
> +static struct backlight_device *
> +visionox_r66451_create_backlight(struct mipi_dsi_device *dsi)
> +{
> +	struct device *dev = &dsi->dev;
> +	const struct backlight_properties props = {
> +		.type = BACKLIGHT_RAW,
> +		.brightness = 255,
> +		.max_brightness = 4095,
> +	};
> +
> +	return devm_backlight_device_register(dev, dev_name(dev), dev, dsi,
> +					      &visionox_r66451_bl_ops, &props);
> +}
> +
> +static int visionox_r66451_probe(struct mipi_dsi_device *dsi)
> +{
> +	struct device *dev = &dsi->dev;
> +	struct visionox_r66451 *ctx;
> +	struct drm_dsc_config *dsc;
> +	int ret = 0;
> +
> +	ctx = devm_kzalloc(dev, sizeof(*ctx), GFP_KERNEL);
> +	if (!ctx)
> +		return -ENOMEM;
> +
> +	dsc = devm_kzalloc(dev, sizeof(*dsc), GFP_KERNEL);
> +	if (!dsc)
> +		return -ENOMEM;
> +
> +	/* Set DSC params */
> +	dsc->dsc_version_major = 0x1;
> +	dsc->dsc_version_minor = 0x2;
> +
> +	dsc->slice_height = 20;
> +	dsc->slice_width = 540;
> +	dsc->slice_count = 2;
> +	dsc->bits_per_component = 8;
> +	dsc->bits_per_pixel = 0x8 << 4;
> +	dsc->block_pred_enable = true;
> +
> +	dsi->dsc = dsc;
> +
> +	ctx->supplies[0].supply = "vddio";
> +	ctx->supplies[1].supply = "vdd";
> +
> +	ret = devm_regulator_bulk_get(&dsi->dev, ARRAY_SIZE(ctx->supplies),
> +			ctx->supplies);
> +
> +	if (ret < 0)
> +		return ret;
> +
> +	ctx->reset_gpio = devm_gpiod_get(dev, "reset", GPIOD_OUT_LOW);
> +	if (IS_ERR(ctx->reset_gpio))
> +		return dev_err_probe(dev, PTR_ERR(ctx->reset_gpio), "Failed to get reset-gpios\n");
> +
> +	ctx->dsi = dsi;
> +	mipi_dsi_set_drvdata(dsi, ctx);
> +
> +	dsi->lanes = 4;
> +	dsi->format = MIPI_DSI_FMT_RGB888;
> +	dsi->mode_flags = MIPI_DSI_MODE_LPM | MIPI_DSI_CLOCK_NON_CONTINUOUS;
> +
> +	drm_panel_init(&ctx->panel, dev, &visionox_r66451_funcs, DRM_MODE_CONNECTOR_DSI);
> +	ctx->panel.backlight = visionox_r66451_create_backlight(dsi);
> +	if (IS_ERR(ctx->panel.backlight))
> +		return dev_err_probe(dev, PTR_ERR(ctx->panel.backlight),
> +				"Failed to create backlight\n");
> +
> +	drm_panel_add(&ctx->panel);
> +
> +	ret = mipi_dsi_attach(dsi);
> +	if (ret < 0) {
> +		dev_err(dev, "Failed to attach to DSI host: %d\n", ret);
> +		drm_panel_remove(&ctx->panel);
> +	}
> +
> +	return ret;
> +}
> +
> +static void visionox_r66451_remove(struct mipi_dsi_device *dsi)
> +{
> +	struct visionox_r66451 *ctx = mipi_dsi_get_drvdata(dsi);
> +	int ret;
> +
> +	ret = mipi_dsi_detach(dsi);
> +	if (ret < 0)
> +		dev_err(&dsi->dev, "Failed to detach DSI host: %d\n", ret);
> +
> +	drm_panel_remove(&ctx->panel);
> +}
> +
> +static const struct of_device_id visionox_r66451_of_match[] = {
> +	{.compatible = "visionox,r66451"},
> +	{ /*sentinel*/ }
> +};
> +MODULE_DEVICE_TABLE(of, visionox_r66451_of_match);
> +
> +static struct mipi_dsi_driver visionox_r66451_driver = {
> +	.probe = visionox_r66451_probe,
> +	.remove = visionox_r66451_remove,
> +	.driver = {
> +		.name = "panel-visionox-r66451",
> +		.of_match_table = visionox_r66451_of_match,
> +	},
> +};
> +
> +module_mipi_dsi_driver(visionox_r66451_driver);
> +
> +MODULE_AUTHOR("Jessica Zhang <quic_jesszhan@quicinc.com>");
> +MODULE_DESCRIPTION("Panel driver for the Visionox R66451 AMOLED DSI panel");
> +MODULE_LICENSE("GPL");
> 

-- 
With best wishes
Dmitry