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Date: Mon, 22 May 2023 11:04:42 +0200
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From: Neil Armstrong <neil.armstrong@linaro.org>
Subject: Re: [PATCH RFC 03/10] drm/panel: Add LGD panel driver for Sony Xperia
 XZ3
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To: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>,
 Marijn Suijten <marijn.suijten@somainline.org>,
 Sam Ravnborg <sam@ravnborg.org>, David Airlie <airlied@gmail.com>,
 Daniel Vetter <daniel@ffwll.ch>, Caleb Connolly <caleb@connolly.tech>,
 Rob Herring <robh+dt@kernel.org>,
 Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
 Conor Dooley <conor+dt@kernel.org>, Andy Gross <agross@kernel.org>,
 Bjorn Andersson <andersson@kernel.org>
References: <20230521-drm-panels-sony-v1-0-541c341d6bee@somainline.org>
 <20230521-drm-panels-sony-v1-3-541c341d6bee@somainline.org>
 <ccc97880-8e74-b85b-9679-9c12c44c4b99@linaro.org>
Organization: Linaro Developer Services
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Reply-To: neil.armstrong@linaro.org
Cc: devicetree@vger.kernel.org, Jami Kettunen <jami.kettunen@somainline.org>,
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 dri-devel@lists.freedesktop.org, Abhinav Kumar <quic_abhinavk@quicinc.com>,
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On 22/05/2023 03:16, Dmitry Baryshkov wrote:
> On 22/05/2023 00:23, Marijn Suijten wrote:
>> Sony provides an unlabeled LGD + Atmel maXTouch assembly in its Xperia
>> XZ3 (tama akatsuki) phone, with custom DCS commands to match.
>>
>> This panel features Display Stream Compression 1.1.
>>
>> Signed-off-by: Marijn Suijten <marijn.suijten@somainline.org>
>> ---
>>   drivers/gpu/drm/panel/Kconfig                   |  11 +
>>   drivers/gpu/drm/panel/Makefile                  |   1 +
>>   drivers/gpu/drm/panel/panel-sony-akatsuki-lgd.c | 362 ++++++++++++++++++++++++
>>   3 files changed, 374 insertions(+)
>>
>> diff --git a/drivers/gpu/drm/panel/Kconfig b/drivers/gpu/drm/panel/Kconfig
>> index 67ef898d133f2..18bd116e78a71 100644
>> --- a/drivers/gpu/drm/panel/Kconfig
>> +++ b/drivers/gpu/drm/panel/Kconfig
>> @@ -706,6 +706,17 @@ config DRM_PANEL_SONY_ACX565AKM
>>         Say Y here if you want to enable support for the Sony ACX565AKM
>>         800x600 3.5" panel (found on the Nokia N900).
>> +config DRM_PANEL_SONY_AKATSUKI_LGD
>> +    tristate "Sony Xperia XZ3 LGD panel"
>> +    depends on GPIOLIB && OF
>> +    depends on DRM_MIPI_DSI
>> +    depends on BACKLIGHT_CLASS_DEVICE
>> +    help
>> +      Say Y here if you want to enable support for the Sony Xperia XZ3
>> +      1440x2880@60 6.0" OLED DSI cmd mode panel produced by LG Display.
>> +
>> +      This panel uses Display Stream Compression 1.1.
>> +
>>   config DRM_PANEL_SONY_TD4353_JDI
>>       tristate "Sony TD4353 JDI panel"
>>       depends on GPIOLIB && OF
>> diff --git a/drivers/gpu/drm/panel/Makefile b/drivers/gpu/drm/panel/Makefile
>> index ff169781e82d7..85133f73558f3 100644
>> --- a/drivers/gpu/drm/panel/Makefile
>> +++ b/drivers/gpu/drm/panel/Makefile
>> @@ -71,6 +71,7 @@ obj-$(CONFIG_DRM_PANEL_SITRONIX_ST7701) += panel-sitronix-st7701.o
>>   obj-$(CONFIG_DRM_PANEL_SITRONIX_ST7703) += panel-sitronix-st7703.o
>>   obj-$(CONFIG_DRM_PANEL_SITRONIX_ST7789V) += panel-sitronix-st7789v.o
>>   obj-$(CONFIG_DRM_PANEL_SONY_ACX565AKM) += panel-sony-acx565akm.o
>> +obj-$(CONFIG_DRM_PANEL_SONY_AKATSUKI_LGD) += panel-sony-akatsuki-lgd.o
>>   obj-$(CONFIG_DRM_PANEL_SONY_TD4353_JDI) += panel-sony-td4353-jdi.o
>>   obj-$(CONFIG_DRM_PANEL_SONY_TULIP_TRULY_NT35521) += panel-sony-tulip-truly-nt35521.o
>>   obj-$(CONFIG_DRM_PANEL_TDO_TL070WSH30) += panel-tdo-tl070wsh30.o
>> diff --git a/drivers/gpu/drm/panel/panel-sony-akatsuki-lgd.c b/drivers/gpu/drm/panel/panel-sony-akatsuki-lgd.c
>> new file mode 100644
>> index 0000000000000..f55788f963dab
>> --- /dev/null
>> +++ b/drivers/gpu/drm/panel/panel-sony-akatsuki-lgd.c
>> @@ -0,0 +1,362 @@
>> +// SPDX-License-Identifier: GPL-2.0-only
>> +/*
>> + * Copyright (c) 2023 Marijn Suijten <marijn.suijten@somainline.org>
>> + *
>> + * Based on Sony Downstream's "Atmel LGD ID5" Akatsuki panel dtsi.
>> + */
>> +
>> +#include <linux/backlight.h>
>> +#include <linux/delay.h>
>> +#include <linux/gpio/consumer.h>
>> +#include <linux/module.h>
>> +#include <linux/of.h>
>> +#include <linux/of_device.h>
>> +#include <linux/regulator/consumer.h>
>> +
>> +#include <video/mipi_display.h>
>> +
>> +#include <drm/drm_mipi_dsi.h>
>> +#include <drm/drm_modes.h>
>> +#include <drm/drm_panel.h>
>> +#include <drm/drm_probe_helper.h>
>> +#include <drm/display/drm_dsc.h>
>> +#include <drm/display/drm_dsc_helper.h>
>> +
>> +struct sony_akatsuki_lgd {
>> +    struct drm_panel panel;
>> +    struct mipi_dsi_device *dsi;
>> +    struct regulator *vddio;
>> +    struct gpio_desc *reset_gpio;
>> +    bool prepared;
>> +};
>> +
>> +static inline struct sony_akatsuki_lgd *to_sony_akatsuki_lgd(struct drm_panel *panel)
>> +{
>> +    return container_of(panel, struct sony_akatsuki_lgd, panel);
>> +}
>> +
>> +static int sony_akatsuki_lgd_on(struct sony_akatsuki_lgd *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, 0x7f, 0x5a, 0x5a);
>> +    mipi_dsi_dcs_write_seq(dsi, 0xf0, 0x5a, 0x5a);
>> +    mipi_dsi_dcs_write_seq(dsi, 0xf1, 0x5a, 0x5a);
>> +    mipi_dsi_dcs_write_seq(dsi, 0xf2, 0x5a, 0x5a);
>> +    mipi_dsi_dcs_write_seq(dsi, 0x02, 0x01);
>> +    mipi_dsi_dcs_write_seq(dsi, 0x59, 0x01);
>> +    /* Enable backlight control */
>> +    mipi_dsi_dcs_write_seq(dsi, MIPI_DCS_WRITE_CONTROL_DISPLAY, BIT(5));
>> +    mipi_dsi_dcs_write_seq(dsi, 0x57, 0x20, 0x80, 0xde, 0x60, 0x00);
>> +
>> +    ret = mipi_dsi_dcs_set_column_address(dsi, 0, 1440 - 1);
>> +    if (ret < 0) {
>> +        dev_err(dev, "Failed to set column address: %d\n", ret);
>> +        return ret;
>> +    }
>> +
>> +    ret = mipi_dsi_dcs_set_page_address(dsi, 0, 2880 - 1);
>> +    if (ret < 0) {
>> +        dev_err(dev, "Failed to set page address: %d\n", ret);
>> +        return ret;
>> +    }
>> +
>> +    mipi_dsi_dcs_write_seq(dsi, MIPI_DCS_WRITE_POWER_SAVE, 0x00);
>> +
>> +    ret = mipi_dsi_dcs_set_tear_on(dsi, MIPI_DSI_DCS_TEAR_MODE_VBLANK);
>> +    if (ret < 0) {
>> +        dev_err(dev, "Failed to set tear on: %d\n", ret);
>> +        return ret;
>> +    }
>> +
>> +    mipi_dsi_dcs_write_seq(dsi, 0x7f, 0x5a, 0x5a);
>> +    mipi_dsi_dcs_write_seq(dsi, 0xf0, 0x5a, 0x5a);
>> +    mipi_dsi_dcs_write_seq(dsi, 0xf1, 0x5a, 0x5a);
>> +    mipi_dsi_dcs_write_seq(dsi, 0xf2, 0x5a, 0x5a);
>> +    mipi_dsi_dcs_write_seq(dsi, 0xb0, 0x03);
>> +    mipi_dsi_dcs_write_seq(dsi, 0xf6, 0x04);
>> +    mipi_dsi_dcs_write_seq(dsi, 0xb0, 0x05);
>> +    mipi_dsi_dcs_write_seq(dsi, 0xf6, 0x01, 0x7f, 0x00);
>> +
>> +    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);
>> +
>> +    mipi_dsi_dcs_write_seq(dsi, 0xe3, 0xac, 0x19, 0x34, 0x14, 0x7d);
>> +
>> +    ret = mipi_dsi_dcs_set_display_on(dsi);
>> +    if (ret < 0) {
>> +        dev_err(dev, "Failed to turn display on: %d\n", ret);
>> +        return ret;
>> +    }
> 
> My usual question: should the mipi_dsi_dcs_exit_sleep_mode() / mipi_dsi_dcs_set_display_on() be moved from prepare() to enable() part?


No, prepare is called before the video stream is started and when display is still in LPM mode and the mode hasn't been set.

Neil

> 
>> +
>> +    return 0;
>> +}
>> +
>> +static int sony_akatsuki_lgd_off(struct sony_akatsuki_lgd *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 turn display off: %d\n", ret);
>> +        return ret;
>> +    }
>> +    msleep(20);
>> +
>> +    ret = mipi_dsi_dcs_set_tear_off(dsi);
>> +    if (ret < 0) {
>> +        dev_err(dev, "Failed to set tear off: %d\n", ret);
>> +        return ret;
>> +    }
>> +
>> +    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(100);
>> +
>> +    return 0;
>> +}
>> +
>> +static int sony_akatsuki_lgd_prepare(struct drm_panel *panel)
>> +{
>> +    struct sony_akatsuki_lgd *ctx = to_sony_akatsuki_lgd(panel);
>> +    struct drm_dsc_picture_parameter_set pps;
>> +    struct device *dev = &ctx->dsi->dev;
>> +    int ret;
>> +
>> +    if (ctx->prepared)
>> +        return 0;
>> +
>> +    ret = regulator_enable(ctx->vddio);
>> +    if (ret < 0) {
>> +        dev_err(dev, "Failed to enable vddio regulator: %d\n", ret);
>> +        return ret;
>> +    }
>> +
>> +    msleep(100);
>> +
>> +    gpiod_set_value_cansleep(ctx->reset_gpio, 1);
>> +    usleep_range(5000, 5100);
>> +
>> +    ret = sony_akatsuki_lgd_on(ctx);
>> +    if (ret < 0) {
>> +        dev_err(dev, "Failed to power on panel: %d\n", ret);
>> +        goto fail;
>> +    }
>> +
>> +    if (ctx->dsi->dsc) {
> 
> dsi->dsc is always set, thus this condition can be dropped.
> 
>> +        drm_dsc_pps_payload_pack(&pps, ctx->dsi->dsc);
>> +
>> +        ret = mipi_dsi_picture_parameter_set(ctx->dsi, &pps);
>> +        if (ret < 0) {
>> +            dev_err(panel->dev, "failed to transmit PPS: %d\n", ret);
>> +            goto fail;
>> +        }
>> +        ret = mipi_dsi_compression_mode(ctx->dsi, true);
>> +        if (ret < 0) {
>> +            dev_err(dev, "failed to enable compression mode: %d\n", ret);
>> +            goto fail;
>> +        }
>> +
>> +        msleep(28);
>> +    }
>> +
>> +    ctx->prepared = true;
>> +    return 0;
>> +
>> +fail:
>> +    gpiod_set_value_cansleep(ctx->reset_gpio, 0);
>> +    regulator_disable(ctx->vddio);
>> +    return ret;
>> +}
>> +
>> +static int sony_akatsuki_lgd_unprepare(struct drm_panel *panel)
>> +{
>> +    struct sony_akatsuki_lgd *ctx = to_sony_akatsuki_lgd(panel);
>> +    struct device *dev = &ctx->dsi->dev;
>> +    int ret;
>> +
>> +    if (!ctx->prepared)
>> +        return 0;
>> +
>> +    ret = sony_akatsuki_lgd_off(ctx);
>> +    if (ret < 0)
>> +        dev_err(dev, "Failed to power off panel: %d\n", ret);
>> +
>> +    gpiod_set_value_cansleep(ctx->reset_gpio, 0);
>> +    regulator_disable(ctx->vddio);
>> +
>> +    usleep_range(5000, 5100);
>> +
>> +    ctx->prepared = false;
>> +    return 0;
>> +}
>> +
>> +static const struct drm_display_mode sony_akatsuki_lgd_mode = {
>> +    .clock = (1440 + 312 + 8 + 8) * (2880 + 48 + 8 + 8) * 60 / 1000,
>> +    .hdisplay = 1440,
>> +    .hsync_start = 1440 + 312,
>> +    .hsync_end = 1440 + 312 + 8,
>> +    .htotal = 1440 + 312 + 8 + 8,
>> +    .vdisplay = 2880,
>> +    .vsync_start = 2880 + 48,
>> +    .vsync_end = 2880 + 48 + 8,
>> +    .vtotal = 2880 + 48 + 8 + 8,
>> +    .width_mm = 68,
>> +    .height_mm = 136,
>> +};
>> +
>> +static int sony_akatsuki_lgd_get_modes(struct drm_panel *panel,
>> +                   struct drm_connector *connector)
>> +{
>> +    return drm_connector_helper_get_modes_fixed(connector, &sony_akatsuki_lgd_mode);
>> +}
>> +
>> +static const struct drm_panel_funcs sony_akatsuki_lgd_panel_funcs = {
>> +    .prepare = sony_akatsuki_lgd_prepare,
>> +    .unprepare = sony_akatsuki_lgd_unprepare,
>> +    .get_modes = sony_akatsuki_lgd_get_modes,
>> +};
>> +
>> +static int sony_akatsuki_lgd_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_large(dsi, brightness);
>> +}
>> +
>> +static int sony_akatsuki_lgd_bl_get_brightness(struct backlight_device *bl)
>> +{
>> +    struct mipi_dsi_device *dsi = bl_get_data(bl);
>> +    u16 brightness;
>> +    int ret;
>> +
>> +    ret = mipi_dsi_dcs_get_display_brightness_large(dsi, &brightness);
>> +    if (ret < 0)
>> +        return ret;
>> +
>> +    return brightness & 0x3ff;
>> +}
>> +
>> +static const struct backlight_ops sony_akatsuki_lgd_bl_ops = {
>> +    .update_status = sony_akatsuki_lgd_bl_update_status,
>> +    .get_brightness = sony_akatsuki_lgd_bl_get_brightness,
>> +};
>> +
>> +static int sony_akatsuki_lgd_probe(struct mipi_dsi_device *dsi)
>> +{
>> +    const struct backlight_properties props = {
>> +        .type = BACKLIGHT_RAW,
>> +        .brightness = 100,
>> +        .max_brightness = 1023,
>> +    };
>> +    struct device *dev = &dsi->dev;
>> +    struct sony_akatsuki_lgd *ctx;
>> +    struct drm_dsc_config *dsc;
>> +    int ret;
>> +
>> +    ctx = devm_kzalloc(dev, sizeof(*ctx), GFP_KERNEL);
>> +    if (!ctx)
>> +        return -ENOMEM;
>> +
>> +    ctx->vddio = devm_regulator_get(dev, "vddio");
>> +    if (IS_ERR(ctx->vddio))
>> +        return dev_err_probe(dev, PTR_ERR(ctx->vddio),
>> +                     "Failed to get vddio\n");
>> +
>> +    ctx->reset_gpio = devm_gpiod_get(dev, "reset", GPIOD_ASIS);
>> +    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_CLOCK_NON_CONTINUOUS;
>> +
>> +    drm_panel_init(&ctx->panel, dev, &sony_akatsuki_lgd_panel_funcs,
>> +               DRM_MODE_CONNECTOR_DSI);
>> +
>> +    ctx->panel.backlight = devm_backlight_device_register(dev, dev_name(dev), dev, dsi,
>> +                          &sony_akatsuki_lgd_bl_ops, &props);
>> +    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);
>> +
>> +    /* This panel only supports DSC; unconditionally enable it */
>> +    dsi->dsc = dsc = devm_kzalloc(&dsi->dev, sizeof(*dsc), GFP_KERNEL);
> 
> I think double assignments are frowned upon.
> 
>> +    if (!dsc)
>> +        return -ENOMEM;
>> +
>> +    dsc->dsc_version_major = 1;
>> +    dsc->dsc_version_minor = 1;
>> +
>> +    dsc->slice_height = 32;
>> +    dsc->slice_count = 2;
>> +    // TODO: Get hdisplay from the mode
> 
> Would you like to fix the TODO?
> 
>> +    WARN_ON(1440 % dsc->slice_count);
>> +    dsc->slice_width = 1440 / dsc->slice_count;
>> +    dsc->bits_per_component = 8;
>> +    dsc->bits_per_pixel = 8 << 4; /* 4 fractional bits */
>> +    dsc->block_pred_enable = true;
>> +
>> +    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;
>> +    }
>> +
>> +    return 0;
>> +}
>> +
>> +static void sony_akatsuki_lgd_remove(struct mipi_dsi_device *dsi)
>> +{
>> +    struct sony_akatsuki_lgd *ctx = mipi_dsi_get_drvdata(dsi);
>> +    int ret;
>> +
>> +    ret = mipi_dsi_detach(dsi);
>> +    if (ret < 0)
>> +        dev_err(&dsi->dev, "Failed to detach from DSI host: %d\n", ret);
>> +
>> +    drm_panel_remove(&ctx->panel);
>> +}
>> +
>> +static const struct of_device_id sony_akatsuki_lgd_of_match[] = {
>> +    { .compatible = "sony,akatsuki-lgd" },
>> +    { /* sentinel */ }
>> +};
>> +MODULE_DEVICE_TABLE(of, sony_akatsuki_lgd_of_match);
>> +
>> +static struct mipi_dsi_driver sony_akatsuki_lgd_driver = {
>> +    .probe = sony_akatsuki_lgd_probe,
>> +    .remove = sony_akatsuki_lgd_remove,
>> +    .driver = {
>> +        .name = "panel-sony-akatsuki-lgd",
>> +        .of_match_table = sony_akatsuki_lgd_of_match,
>> +    },
>> +};
>> +module_mipi_dsi_driver(sony_akatsuki_lgd_driver);
>> +
>> +MODULE_AUTHOR("Marijn Suijten <marijn.suijten@somainline.org>");
>> +MODULE_DESCRIPTION("DRM panel driver for an unnamed LGD OLED panel found in the Sony Xperia XZ3");
>> +MODULE_LICENSE("GPL");
>>
> 


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Message-ID: <71675a02-0801-62dc-2673-4a0907636b21@linaro.org>
Date:   Mon, 22 May 2023 11:04:42 +0200
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From:   Neil Armstrong <neil.armstrong@linaro.org>
Reply-To: neil.armstrong@linaro.org
Subject: Re: [PATCH RFC 03/10] drm/panel: Add LGD panel driver for Sony Xperia
 XZ3
Content-Language: en-US
To:     Dmitry Baryshkov <dmitry.baryshkov@linaro.org>,
        Marijn Suijten <marijn.suijten@somainline.org>,
        Sam Ravnborg <sam@ravnborg.org>,
        David Airlie <airlied@gmail.com>,
        Daniel Vetter <daniel@ffwll.ch>,
        Caleb Connolly <caleb@connolly.tech>,
        Rob Herring <robh+dt@kernel.org>,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
        Conor Dooley <conor+dt@kernel.org>,
        Andy Gross <agross@kernel.org>,
        Bjorn Andersson <andersson@kernel.org>
Cc:     ~postmarketos/upstreaming@lists.sr.ht,
        AngeloGioacchino Del Regno 
        <angelogioacchino.delregno@somainline.org>,
        Konrad Dybcio <konrad.dybcio@linaro.org>,
        Martin Botka <martin.botka@somainline.org>,
        Jami Kettunen <jami.kettunen@somainline.org>,
        dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org,
        devicetree@vger.kernel.org, linux-arm-msm@vger.kernel.org,
        Abhinav Kumar <quic_abhinavk@quicinc.com>,
        Kuogee Hsieh <quic_khsieh@quicinc.com>,
        Jessica Zhang <quic_jesszhan@quicinc.com>
References: <20230521-drm-panels-sony-v1-0-541c341d6bee@somainline.org>
 <20230521-drm-panels-sony-v1-3-541c341d6bee@somainline.org>
 <ccc97880-8e74-b85b-9679-9c12c44c4b99@linaro.org>
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On 22/05/2023 03:16, Dmitry Baryshkov wrote:
> On 22/05/2023 00:23, Marijn Suijten wrote:
>> Sony provides an unlabeled LGD + Atmel maXTouch assembly in its Xperia
>> XZ3 (tama akatsuki) phone, with custom DCS commands to match.
>>
>> This panel features Display Stream Compression 1.1.
>>
>> Signed-off-by: Marijn Suijten <marijn.suijten@somainline.org>
>> ---
>>   drivers/gpu/drm/panel/Kconfig                   |  11 +
>>   drivers/gpu/drm/panel/Makefile                  |   1 +
>>   drivers/gpu/drm/panel/panel-sony-akatsuki-lgd.c | 362 ++++++++++++++++++++++++
>>   3 files changed, 374 insertions(+)
>>
>> diff --git a/drivers/gpu/drm/panel/Kconfig b/drivers/gpu/drm/panel/Kconfig
>> index 67ef898d133f2..18bd116e78a71 100644
>> --- a/drivers/gpu/drm/panel/Kconfig
>> +++ b/drivers/gpu/drm/panel/Kconfig
>> @@ -706,6 +706,17 @@ config DRM_PANEL_SONY_ACX565AKM
>>         Say Y here if you want to enable support for the Sony ACX565AKM
>>         800x600 3.5" panel (found on the Nokia N900).
>> +config DRM_PANEL_SONY_AKATSUKI_LGD
>> +    tristate "Sony Xperia XZ3 LGD panel"
>> +    depends on GPIOLIB && OF
>> +    depends on DRM_MIPI_DSI
>> +    depends on BACKLIGHT_CLASS_DEVICE
>> +    help
>> +      Say Y here if you want to enable support for the Sony Xperia XZ3
>> +      1440x2880@60 6.0" OLED DSI cmd mode panel produced by LG Display.
>> +
>> +      This panel uses Display Stream Compression 1.1.
>> +
>>   config DRM_PANEL_SONY_TD4353_JDI
>>       tristate "Sony TD4353 JDI panel"
>>       depends on GPIOLIB && OF
>> diff --git a/drivers/gpu/drm/panel/Makefile b/drivers/gpu/drm/panel/Makefile
>> index ff169781e82d7..85133f73558f3 100644
>> --- a/drivers/gpu/drm/panel/Makefile
>> +++ b/drivers/gpu/drm/panel/Makefile
>> @@ -71,6 +71,7 @@ obj-$(CONFIG_DRM_PANEL_SITRONIX_ST7701) += panel-sitronix-st7701.o
>>   obj-$(CONFIG_DRM_PANEL_SITRONIX_ST7703) += panel-sitronix-st7703.o
>>   obj-$(CONFIG_DRM_PANEL_SITRONIX_ST7789V) += panel-sitronix-st7789v.o
>>   obj-$(CONFIG_DRM_PANEL_SONY_ACX565AKM) += panel-sony-acx565akm.o
>> +obj-$(CONFIG_DRM_PANEL_SONY_AKATSUKI_LGD) += panel-sony-akatsuki-lgd.o
>>   obj-$(CONFIG_DRM_PANEL_SONY_TD4353_JDI) += panel-sony-td4353-jdi.o
>>   obj-$(CONFIG_DRM_PANEL_SONY_TULIP_TRULY_NT35521) += panel-sony-tulip-truly-nt35521.o
>>   obj-$(CONFIG_DRM_PANEL_TDO_TL070WSH30) += panel-tdo-tl070wsh30.o
>> diff --git a/drivers/gpu/drm/panel/panel-sony-akatsuki-lgd.c b/drivers/gpu/drm/panel/panel-sony-akatsuki-lgd.c
>> new file mode 100644
>> index 0000000000000..f55788f963dab
>> --- /dev/null
>> +++ b/drivers/gpu/drm/panel/panel-sony-akatsuki-lgd.c
>> @@ -0,0 +1,362 @@
>> +// SPDX-License-Identifier: GPL-2.0-only
>> +/*
>> + * Copyright (c) 2023 Marijn Suijten <marijn.suijten@somainline.org>
>> + *
>> + * Based on Sony Downstream's "Atmel LGD ID5" Akatsuki panel dtsi.
>> + */
>> +
>> +#include <linux/backlight.h>
>> +#include <linux/delay.h>
>> +#include <linux/gpio/consumer.h>
>> +#include <linux/module.h>
>> +#include <linux/of.h>
>> +#include <linux/of_device.h>
>> +#include <linux/regulator/consumer.h>
>> +
>> +#include <video/mipi_display.h>
>> +
>> +#include <drm/drm_mipi_dsi.h>
>> +#include <drm/drm_modes.h>
>> +#include <drm/drm_panel.h>
>> +#include <drm/drm_probe_helper.h>
>> +#include <drm/display/drm_dsc.h>
>> +#include <drm/display/drm_dsc_helper.h>
>> +
>> +struct sony_akatsuki_lgd {
>> +    struct drm_panel panel;
>> +    struct mipi_dsi_device *dsi;
>> +    struct regulator *vddio;
>> +    struct gpio_desc *reset_gpio;
>> +    bool prepared;
>> +};
>> +
>> +static inline struct sony_akatsuki_lgd *to_sony_akatsuki_lgd(struct drm_panel *panel)
>> +{
>> +    return container_of(panel, struct sony_akatsuki_lgd, panel);
>> +}
>> +
>> +static int sony_akatsuki_lgd_on(struct sony_akatsuki_lgd *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, 0x7f, 0x5a, 0x5a);
>> +    mipi_dsi_dcs_write_seq(dsi, 0xf0, 0x5a, 0x5a);
>> +    mipi_dsi_dcs_write_seq(dsi, 0xf1, 0x5a, 0x5a);
>> +    mipi_dsi_dcs_write_seq(dsi, 0xf2, 0x5a, 0x5a);
>> +    mipi_dsi_dcs_write_seq(dsi, 0x02, 0x01);
>> +    mipi_dsi_dcs_write_seq(dsi, 0x59, 0x01);
>> +    /* Enable backlight control */
>> +    mipi_dsi_dcs_write_seq(dsi, MIPI_DCS_WRITE_CONTROL_DISPLAY, BIT(5));
>> +    mipi_dsi_dcs_write_seq(dsi, 0x57, 0x20, 0x80, 0xde, 0x60, 0x00);
>> +
>> +    ret = mipi_dsi_dcs_set_column_address(dsi, 0, 1440 - 1);
>> +    if (ret < 0) {
>> +        dev_err(dev, "Failed to set column address: %d\n", ret);
>> +        return ret;
>> +    }
>> +
>> +    ret = mipi_dsi_dcs_set_page_address(dsi, 0, 2880 - 1);
>> +    if (ret < 0) {
>> +        dev_err(dev, "Failed to set page address: %d\n", ret);
>> +        return ret;
>> +    }
>> +
>> +    mipi_dsi_dcs_write_seq(dsi, MIPI_DCS_WRITE_POWER_SAVE, 0x00);
>> +
>> +    ret = mipi_dsi_dcs_set_tear_on(dsi, MIPI_DSI_DCS_TEAR_MODE_VBLANK);
>> +    if (ret < 0) {
>> +        dev_err(dev, "Failed to set tear on: %d\n", ret);
>> +        return ret;
>> +    }
>> +
>> +    mipi_dsi_dcs_write_seq(dsi, 0x7f, 0x5a, 0x5a);
>> +    mipi_dsi_dcs_write_seq(dsi, 0xf0, 0x5a, 0x5a);
>> +    mipi_dsi_dcs_write_seq(dsi, 0xf1, 0x5a, 0x5a);
>> +    mipi_dsi_dcs_write_seq(dsi, 0xf2, 0x5a, 0x5a);
>> +    mipi_dsi_dcs_write_seq(dsi, 0xb0, 0x03);
>> +    mipi_dsi_dcs_write_seq(dsi, 0xf6, 0x04);
>> +    mipi_dsi_dcs_write_seq(dsi, 0xb0, 0x05);
>> +    mipi_dsi_dcs_write_seq(dsi, 0xf6, 0x01, 0x7f, 0x00);
>> +
>> +    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);
>> +
>> +    mipi_dsi_dcs_write_seq(dsi, 0xe3, 0xac, 0x19, 0x34, 0x14, 0x7d);
>> +
>> +    ret = mipi_dsi_dcs_set_display_on(dsi);
>> +    if (ret < 0) {
>> +        dev_err(dev, "Failed to turn display on: %d\n", ret);
>> +        return ret;
>> +    }
> 
> My usual question: should the mipi_dsi_dcs_exit_sleep_mode() / mipi_dsi_dcs_set_display_on() be moved from prepare() to enable() part?


No, prepare is called before the video stream is started and when display is still in LPM mode and the mode hasn't been set.

Neil

> 
>> +
>> +    return 0;
>> +}
>> +
>> +static int sony_akatsuki_lgd_off(struct sony_akatsuki_lgd *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 turn display off: %d\n", ret);
>> +        return ret;
>> +    }
>> +    msleep(20);
>> +
>> +    ret = mipi_dsi_dcs_set_tear_off(dsi);
>> +    if (ret < 0) {
>> +        dev_err(dev, "Failed to set tear off: %d\n", ret);
>> +        return ret;
>> +    }
>> +
>> +    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(100);
>> +
>> +    return 0;
>> +}
>> +
>> +static int sony_akatsuki_lgd_prepare(struct drm_panel *panel)
>> +{
>> +    struct sony_akatsuki_lgd *ctx = to_sony_akatsuki_lgd(panel);
>> +    struct drm_dsc_picture_parameter_set pps;
>> +    struct device *dev = &ctx->dsi->dev;
>> +    int ret;
>> +
>> +    if (ctx->prepared)
>> +        return 0;
>> +
>> +    ret = regulator_enable(ctx->vddio);
>> +    if (ret < 0) {
>> +        dev_err(dev, "Failed to enable vddio regulator: %d\n", ret);
>> +        return ret;
>> +    }
>> +
>> +    msleep(100);
>> +
>> +    gpiod_set_value_cansleep(ctx->reset_gpio, 1);
>> +    usleep_range(5000, 5100);
>> +
>> +    ret = sony_akatsuki_lgd_on(ctx);
>> +    if (ret < 0) {
>> +        dev_err(dev, "Failed to power on panel: %d\n", ret);
>> +        goto fail;
>> +    }
>> +
>> +    if (ctx->dsi->dsc) {
> 
> dsi->dsc is always set, thus this condition can be dropped.
> 
>> +        drm_dsc_pps_payload_pack(&pps, ctx->dsi->dsc);
>> +
>> +        ret = mipi_dsi_picture_parameter_set(ctx->dsi, &pps);
>> +        if (ret < 0) {
>> +            dev_err(panel->dev, "failed to transmit PPS: %d\n", ret);
>> +            goto fail;
>> +        }
>> +        ret = mipi_dsi_compression_mode(ctx->dsi, true);
>> +        if (ret < 0) {
>> +            dev_err(dev, "failed to enable compression mode: %d\n", ret);
>> +            goto fail;
>> +        }
>> +
>> +        msleep(28);
>> +    }
>> +
>> +    ctx->prepared = true;
>> +    return 0;
>> +
>> +fail:
>> +    gpiod_set_value_cansleep(ctx->reset_gpio, 0);
>> +    regulator_disable(ctx->vddio);
>> +    return ret;
>> +}
>> +
>> +static int sony_akatsuki_lgd_unprepare(struct drm_panel *panel)
>> +{
>> +    struct sony_akatsuki_lgd *ctx = to_sony_akatsuki_lgd(panel);
>> +    struct device *dev = &ctx->dsi->dev;
>> +    int ret;
>> +
>> +    if (!ctx->prepared)
>> +        return 0;
>> +
>> +    ret = sony_akatsuki_lgd_off(ctx);
>> +    if (ret < 0)
>> +        dev_err(dev, "Failed to power off panel: %d\n", ret);
>> +
>> +    gpiod_set_value_cansleep(ctx->reset_gpio, 0);
>> +    regulator_disable(ctx->vddio);
>> +
>> +    usleep_range(5000, 5100);
>> +
>> +    ctx->prepared = false;
>> +    return 0;
>> +}
>> +
>> +static const struct drm_display_mode sony_akatsuki_lgd_mode = {
>> +    .clock = (1440 + 312 + 8 + 8) * (2880 + 48 + 8 + 8) * 60 / 1000,
>> +    .hdisplay = 1440,
>> +    .hsync_start = 1440 + 312,
>> +    .hsync_end = 1440 + 312 + 8,
>> +    .htotal = 1440 + 312 + 8 + 8,
>> +    .vdisplay = 2880,
>> +    .vsync_start = 2880 + 48,
>> +    .vsync_end = 2880 + 48 + 8,
>> +    .vtotal = 2880 + 48 + 8 + 8,
>> +    .width_mm = 68,
>> +    .height_mm = 136,
>> +};
>> +
>> +static int sony_akatsuki_lgd_get_modes(struct drm_panel *panel,
>> +                   struct drm_connector *connector)
>> +{
>> +    return drm_connector_helper_get_modes_fixed(connector, &sony_akatsuki_lgd_mode);
>> +}
>> +
>> +static const struct drm_panel_funcs sony_akatsuki_lgd_panel_funcs = {
>> +    .prepare = sony_akatsuki_lgd_prepare,
>> +    .unprepare = sony_akatsuki_lgd_unprepare,
>> +    .get_modes = sony_akatsuki_lgd_get_modes,
>> +};
>> +
>> +static int sony_akatsuki_lgd_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_large(dsi, brightness);
>> +}
>> +
>> +static int sony_akatsuki_lgd_bl_get_brightness(struct backlight_device *bl)
>> +{
>> +    struct mipi_dsi_device *dsi = bl_get_data(bl);
>> +    u16 brightness;
>> +    int ret;
>> +
>> +    ret = mipi_dsi_dcs_get_display_brightness_large(dsi, &brightness);
>> +    if (ret < 0)
>> +        return ret;
>> +
>> +    return brightness & 0x3ff;
>> +}
>> +
>> +static const struct backlight_ops sony_akatsuki_lgd_bl_ops = {
>> +    .update_status = sony_akatsuki_lgd_bl_update_status,
>> +    .get_brightness = sony_akatsuki_lgd_bl_get_brightness,
>> +};
>> +
>> +static int sony_akatsuki_lgd_probe(struct mipi_dsi_device *dsi)
>> +{
>> +    const struct backlight_properties props = {
>> +        .type = BACKLIGHT_RAW,
>> +        .brightness = 100,
>> +        .max_brightness = 1023,
>> +    };
>> +    struct device *dev = &dsi->dev;
>> +    struct sony_akatsuki_lgd *ctx;
>> +    struct drm_dsc_config *dsc;
>> +    int ret;
>> +
>> +    ctx = devm_kzalloc(dev, sizeof(*ctx), GFP_KERNEL);
>> +    if (!ctx)
>> +        return -ENOMEM;
>> +
>> +    ctx->vddio = devm_regulator_get(dev, "vddio");
>> +    if (IS_ERR(ctx->vddio))
>> +        return dev_err_probe(dev, PTR_ERR(ctx->vddio),
>> +                     "Failed to get vddio\n");
>> +
>> +    ctx->reset_gpio = devm_gpiod_get(dev, "reset", GPIOD_ASIS);
>> +    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_CLOCK_NON_CONTINUOUS;
>> +
>> +    drm_panel_init(&ctx->panel, dev, &sony_akatsuki_lgd_panel_funcs,
>> +               DRM_MODE_CONNECTOR_DSI);
>> +
>> +    ctx->panel.backlight = devm_backlight_device_register(dev, dev_name(dev), dev, dsi,
>> +                          &sony_akatsuki_lgd_bl_ops, &props);
>> +    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);
>> +
>> +    /* This panel only supports DSC; unconditionally enable it */
>> +    dsi->dsc = dsc = devm_kzalloc(&dsi->dev, sizeof(*dsc), GFP_KERNEL);
> 
> I think double assignments are frowned upon.
> 
>> +    if (!dsc)
>> +        return -ENOMEM;
>> +
>> +    dsc->dsc_version_major = 1;
>> +    dsc->dsc_version_minor = 1;
>> +
>> +    dsc->slice_height = 32;
>> +    dsc->slice_count = 2;
>> +    // TODO: Get hdisplay from the mode
> 
> Would you like to fix the TODO?
> 
>> +    WARN_ON(1440 % dsc->slice_count);
>> +    dsc->slice_width = 1440 / dsc->slice_count;
>> +    dsc->bits_per_component = 8;
>> +    dsc->bits_per_pixel = 8 << 4; /* 4 fractional bits */
>> +    dsc->block_pred_enable = true;
>> +
>> +    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;
>> +    }
>> +
>> +    return 0;
>> +}
>> +
>> +static void sony_akatsuki_lgd_remove(struct mipi_dsi_device *dsi)
>> +{
>> +    struct sony_akatsuki_lgd *ctx = mipi_dsi_get_drvdata(dsi);
>> +    int ret;
>> +
>> +    ret = mipi_dsi_detach(dsi);
>> +    if (ret < 0)
>> +        dev_err(&dsi->dev, "Failed to detach from DSI host: %d\n", ret);
>> +
>> +    drm_panel_remove(&ctx->panel);
>> +}
>> +
>> +static const struct of_device_id sony_akatsuki_lgd_of_match[] = {
>> +    { .compatible = "sony,akatsuki-lgd" },
>> +    { /* sentinel */ }
>> +};
>> +MODULE_DEVICE_TABLE(of, sony_akatsuki_lgd_of_match);
>> +
>> +static struct mipi_dsi_driver sony_akatsuki_lgd_driver = {
>> +    .probe = sony_akatsuki_lgd_probe,
>> +    .remove = sony_akatsuki_lgd_remove,
>> +    .driver = {
>> +        .name = "panel-sony-akatsuki-lgd",
>> +        .of_match_table = sony_akatsuki_lgd_of_match,
>> +    },
>> +};
>> +module_mipi_dsi_driver(sony_akatsuki_lgd_driver);
>> +
>> +MODULE_AUTHOR("Marijn Suijten <marijn.suijten@somainline.org>");
>> +MODULE_DESCRIPTION("DRM panel driver for an unnamed LGD OLED panel found in the Sony Xperia XZ3");
>> +MODULE_LICENSE("GPL");
>>
>