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Message-ID: <ebc3ff33-6e4f-b107-33c6-f35b03307058@linaro.org>
Date:   Tue, 30 May 2023 01:18:40 +0300
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Subject: Re: [PATCH RFC 03/10] drm/panel: Add LGD panel driver for Sony Xperia
 XZ3
Content-Language: en-GB
To:     Marijn Suijten <marijn.suijten@somainline.org>
Cc:     neil.armstrong@linaro.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>,
        ~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>
 <71675a02-0801-62dc-2673-4a0907636b21@linaro.org>
 <CAA8EJpq=HZqiBZ6bpUNH47VmASuH+Mi5OD5BHmg0TPwtsKHf8w@mail.gmail.com>
 <oxgtbj7qmsdvz5gl4bud64jedmhdmvphjfge7uy6uwulefqfsa@pleslv2zgwbp>
From:   Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
In-Reply-To: <oxgtbj7qmsdvz5gl4bud64jedmhdmvphjfge7uy6uwulefqfsa@pleslv2zgwbp>
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On 30/05/2023 00:07, Marijn Suijten wrote:
> On 2023-05-22 15:58:56, Dmitry Baryshkov wrote:
>> On Mon, 22 May 2023 at 12:04, Neil Armstrong <neil.armstrong@linaro.org> wrote:
>>>
>>> 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.
>>>
>>
>> Yes, that's my point. Shouldn't we enable the panel _after_ starting the stream?
> 
> I have never investigated what it takes to split these functions, but
> some of these panels do show some corruption at startup which may be
> circumvented by powering the panel on after starting the video stream?
> 
> I'm just not sure where to make the split: downstream does describe a
> qcom,mdss-dsi-on-command and qcom,mdss-dsi-post-panel-on-command, where
> the latter only contains set_display_on() (not exit_sleep_mode()).
> It is documented like:
> 
>      same as "qcom,mdss-dsi-on-command" except commands are sent after
>      displaying an image."
> 
> So this seems like the right way to split them up, I'll test this out on
> all submitted panel drivers.

Interesting enough, Neil suggested that sending all the commands during 
pre_enable() is the correct sequence (especially for VIDEO mode panels), 
since not all DSI hosts can send commands after switching to the VIDEO mode.

-- 
With best wishes
Dmitry