On Thu, Nov 14, 2019 at 02:15:25PM +0100, Linus Walleij wrote:
> The Sony ACX424AKP is a command/videomode DSI panel for
> mobile devices. It is used on the ST-Ericsson HREF520
> reference design. We support video mode by default, but
> it is possible to switch the panel into command mode
> by using the bool property "dsi-command-mode".
>
> Cc: Stephan Gerhold <step...@gerhold.net>
> Signed-off-by: Linus Walleij <linus.wall...@linaro.org>
> ---
> ChangeLog v4->v5:
> - Bindings were iterated separately so a jump in versioning.
> - Add Stephan as reviewer.
> ChangeLog v3->v4:
> - No changes just resending with the new binding updates.
> ChangeLog v2->v3:
> - No changes just resending with the new binding updates.
> ChangeLog v1->v2:
> - Fix up the ID read function to split into reading header,
> version and ID, store the version in the struct.
> - Get rid of a surplus semicolon found by the build robot
> while rewriting the above code.
> - Use unsigned int in probe() loop.
> - Set vrefresh to 60Hz, as good as any, the measured vrefresh
> in continous command mode is ~117 Hz.
> - Use a different for() idiom while retrying to read ID
> 5 times.
> - Drop the sync pulse setting, we are not using this, this
> panel uses an event.
> - Use the generic "enforce-video-mode" for video mode
> enforcement.
> ---
> drivers/gpu/drm/panel/Kconfig | 7 +
> drivers/gpu/drm/panel/Makefile | 1 +
> drivers/gpu/drm/panel/panel-sony-acx424akp.c | 540 +++++++++++++++++++
> include/video/mipi_display.h | 1 +
> 4 files changed, 549 insertions(+)
> create mode 100644 drivers/gpu/drm/panel/panel-sony-acx424akp.c
>
> diff --git a/drivers/gpu/drm/panel/Kconfig b/drivers/gpu/drm/panel/Kconfig
> index f152bc4eeb53..959df5bea7d2 100644
> --- a/drivers/gpu/drm/panel/Kconfig
> +++ b/drivers/gpu/drm/panel/Kconfig
> @@ -316,6 +316,13 @@ config DRM_PANEL_SITRONIX_ST7789V
> Say Y here if you want to enable support for the Sitronix
> ST7789V controller for 240x320 LCD panels
>
> +config DRM_PANEL_SONY_ACX424AKP
> + tristate "Sony ACX424AKP DSI command mode panel"
> + depends on OF
> + depends on DRM_MIPI_DSI
> + depends on BACKLIGHT_CLASS_DEVICE
> + select VIDEOMODE_HELPERS
> +
> config DRM_PANEL_SONY_ACX565AKM
> tristate "Sony ACX565AKM panel"
> depends on GPIOLIB && OF && SPI
> diff --git a/drivers/gpu/drm/panel/Makefile b/drivers/gpu/drm/panel/Makefile
> index b6cd39fe0f20..0b51793e3b43 100644
> --- a/drivers/gpu/drm/panel/Makefile
> +++ b/drivers/gpu/drm/panel/Makefile
> @@ -33,6 +33,7 @@ obj-$(CONFIG_DRM_PANEL_SHARP_LS037V7DW01) +=
> panel-sharp-ls037v7dw01.o
> obj-$(CONFIG_DRM_PANEL_SHARP_LS043T1LE01) += panel-sharp-ls043t1le01.o
> obj-$(CONFIG_DRM_PANEL_SITRONIX_ST7701) += panel-sitronix-st7701.o
> obj-$(CONFIG_DRM_PANEL_SITRONIX_ST7789V) += panel-sitronix-st7789v.o
> +obj-$(CONFIG_DRM_PANEL_SONY_ACX424AKP) += panel-sony-acx424akp.o
> obj-$(CONFIG_DRM_PANEL_SONY_ACX565AKM) += panel-sony-acx565akm.o
> obj-$(CONFIG_DRM_PANEL_TPO_TD028TTEC1) += panel-tpo-td028ttec1.o
> obj-$(CONFIG_DRM_PANEL_TPO_TD043MTEA1) += panel-tpo-td043mtea1.o
> diff --git a/drivers/gpu/drm/panel/panel-sony-acx424akp.c
> b/drivers/gpu/drm/panel/panel-sony-acx424akp.c
> new file mode 100644
> index 000000000000..2382b608b67b
> --- /dev/null
> +++ b/drivers/gpu/drm/panel/panel-sony-acx424akp.c
> @@ -0,0 +1,540 @@
> +// SPDX-License-Identifier: GPL-2.0+
> +/*
> + * MIPI-DSI Sony ACX424AKP panel driver. This is a 480x864
> + * AMOLED panel with a command-only DSI interface.
> + *
> + * Copyright (C) Linaro Ltd. 2019
> + * Author: Linus Walleij
> + * Based on code and know-how from Marcus Lorentzon
> + * Copyright (C) ST-Ericsson SA 2010
> + */
> +
> +#include <drm/drm_modes.h>
> +#include <drm/drm_mipi_dsi.h>
> +#include <drm/drm_panel.h>
> +#include <drm/drm_print.h>
> +#include <video/mipi_display.h>
> +
> +#include <linux/gpio/consumer.h>
> +#include <linux/regulator/consumer.h>
> +#include <linux/delay.h>
> +#include <linux/of.h>
> +#include <linux/module.h>
> +#include <linux/backlight.h>
> +
> +#define ACX424_DCS_READ_ID1 0xDA
> +#define ACX424_DCS_READ_ID2 0xDB
> +#define ACX424_DCS_READ_ID3 0xDC
> +
> +#define DISPLAY_SONY_ACX424AKP_ID1 0x811b
> +#define DISPLAY_SONY_ACX424AKP_ID2 0x811a
> +#define DISPLAY_SONY_ACX424AKP_ID3 0x8000
> +
> +struct acx424akp {
> + struct device *dev;
> + struct drm_panel panel;
> + struct backlight_device *bl;
> + struct regulator *supply;
> + struct gpio_desc *reset_gpio;
> + u8 version;
> + bool video_mode;
> +};
> +
> +static const struct drm_display_mode sony_acx424akp_vid_mode = {
> + .clock = 330000,
> + .hdisplay = 480,
> + .hsync_start = 480 + 15,
> + .hsync_end = 480 + 15 + 0,
> + .htotal = 480 + 15 + 0 + 15,
> + .vdisplay = 864,
> + .vsync_start = 864 + 14,
> + .vsync_end = 864 + 14 + 1,
> + .vtotal = 864 + 14 + 1 + 11,
> + .vrefresh = 60,
> + .width_mm = 48,
> + .height_mm = 84,
> + .flags = DRM_MODE_FLAG_PVSYNC,
> +};
> +
> +/*
> + * The timings are not very helpful as the display is used in
> + * command mode using the maximum HS frequency.
> + */
> +static const struct drm_display_mode sony_acx424akp_cmd_mode = {
> + .clock = 420160,
> + .hdisplay = 480,
> + .hsync_start = 480 + 154,
> + .hsync_end = 480 + 154 + 16,
> + .htotal = 480 + 154 + 16 + 32,
> + .vdisplay = 864,
> + .vsync_start = 864 + 1,
> + .vsync_end = 864 + 1 + 1,
> + .vtotal = 864 + 1 + 1 + 1,
> + /*
> + * Some desired refresh rate, experiments at the maximum "pixel"
> + * clock speed (HS clock 420 MHz) yields around 117Hz.
> + */
> + .vrefresh = 60,
> + .width_mm = 48,
> + .height_mm = 84,
> +};
> +
> +static inline struct acx424akp *panel_to_acx424akp(struct drm_panel *panel)
> +{
> + return container_of(panel, struct acx424akp, panel);
> +}
> +
> +#define FOSC 20 /* 20Mhz */
> +#define SCALE_FACTOR_NS_DIV_MHZ 1000
> +
> +static int acx424akp_set_brightness(struct backlight_device *bl)
> +{
> + struct acx424akp *acx = bl_get_data(bl);
> + struct mipi_dsi_device *dsi = to_mipi_dsi_device(acx->dev);
> + int period_ns = 1023;
> + int duty_ns = bl->props.brightness;
> + u8 pwm_ratio;
> + u8 pwm_div;
> + u8 par;
> + int ret;
> +
> + /* Calculate the PWM duty cycle in n/256's */
> + pwm_ratio = max(((duty_ns * 256) / period_ns) - 1, 1);
> + pwm_div = max(1,
> + ((FOSC * period_ns) / 256) /
> + SCALE_FACTOR_NS_DIV_MHZ);
Does this handle the case where brightness = 0 (usually display off)?
I have also often seen code like
if (bl->props.power != FB_BLANK_UNBLANK ||
bl->props.fb_blank != FB_BLANK_UNBLANK ||
bl->props.state & (BL_CORE_SUSPENDED | BL_CORE_FBBLANK))
brightness = 0;
to handle the blanking states. Not sure.
> +
> + /* Set up PWM dutycycle ONE byte (differs from the standard) */
> + DRM_DEV_DEBUG(acx->dev, "calculated duty cycle %02x\n", pwm_ratio);
> + ret = mipi_dsi_dcs_write(dsi, MIPI_DCS_SET_DISPLAY_BRIGHTNESS,
> + &pwm_ratio, 1);
> + if (ret < 0) {
> + DRM_DEV_ERROR(acx->dev,
> + "failed to set display PWM ratio (%d)\n",
> + ret);
> + return ret;
> + }
> +
> + /*
> + * Sequence to write PWMDIV:
> + * address data
> + * 0xF3 0xAA CMD2 Unlock
> + * 0x00 0x01 Enter CMD2 page 0
> + * 0X7D 0x01 No reload MTP of CMD2 P1
> + * 0x22 PWMDIV
> + * 0x7F 0xAA CMD2 page 1 lock
> + */
> + par = 0xaa;
> + ret = mipi_dsi_dcs_write(dsi, 0xf3, &par, 1);
> + if (ret < 0) {
> + DRM_DEV_ERROR(acx->dev,
> + "failed to unlock CMD 2 (%d)\n",
> + ret);
> + return ret;
> + }
> + par = 0x01;
> + ret = mipi_dsi_dcs_write(dsi, 0x00, &par, 1);
> + if (ret < 0) {
> + DRM_DEV_ERROR(acx->dev,
> + "failed to enter page 1 (%d)\n",
> + ret);
> + return ret;
> + }
> + par = 0x01;
> + ret = mipi_dsi_dcs_write(dsi, 0x7d, &par, 1);
> + if (ret < 0) {
> + DRM_DEV_ERROR(acx->dev,
> + "failed to disable MTP reload (%d)\n",
> + ret);
> + return ret;
> + }
> + ret = mipi_dsi_dcs_write(dsi, 0x22, &pwm_div, 1);
> + if (ret < 0) {
> + DRM_DEV_ERROR(acx->dev,
> + "failed to set PWM divisor (%d)\n",
> + ret);
> + return ret;
> + }
> + par = 0xaa;
> + ret = mipi_dsi_dcs_write(dsi, 0x7f, &par, 1);
> + if (ret < 0) {
> + DRM_DEV_ERROR(acx->dev,
> + "failed to lock CMD 2 (%d)\n",
> + ret);
> + return ret;
> + }
> +
> + /* Enable backlight */
> + par = 0x24;
> + ret = mipi_dsi_dcs_write(dsi, MIPI_DCS_WRITE_CONTROL_DISPLAY,
> + &par, 1);
> + if (ret < 0) {
> + DRM_DEV_ERROR(acx->dev,
> + "failed to enable display backlight (%d)\n",
> + ret);
> + return ret;
> + }
> +
> + return 0;
> +}
> +
> +static const struct backlight_ops acx424akp_bl_ops = {
> + .update_status = acx424akp_set_brightness,
> +};
> +
> +static int acx424akp_read_id(struct acx424akp *acx)
> +{
> + struct mipi_dsi_device *dsi = to_mipi_dsi_device(acx->dev);
> + u8 header, version, id;
> + u16 val;
> + int ret;
> +
> + ret = mipi_dsi_dcs_read(dsi, ACX424_DCS_READ_ID1, &header, 1);
> + if (ret < 0) {
> + DRM_DEV_ERROR(acx->dev, "could not read ID header byte\n");
> + return ret;
> + }
> + ret = mipi_dsi_dcs_read(dsi, ACX424_DCS_READ_ID2, &id, 1);
> + if (ret < 0) {
> + DRM_DEV_ERROR(acx->dev, "could not read device ID byte\n");
> + return ret;
> + }
> + ret = mipi_dsi_dcs_read(dsi, ACX424_DCS_READ_ID3, &version, 1);
> + if (ret < 0) {
> + DRM_DEV_ERROR(acx->dev, "could not read version byte\n");
> + return ret;
> + }
> +
> + if (header == 0x00) {
> + DRM_DEV_ERROR(acx->dev, "device ID header is zero\n");
> + return -ENODEV;
> + }
> +
> + val = (id << 8) | version;
> + switch (val) {
> + case DISPLAY_SONY_ACX424AKP_ID1:
> + case DISPLAY_SONY_ACX424AKP_ID2:
> + case DISPLAY_SONY_ACX424AKP_ID3:
> + DRM_DEV_INFO(acx->dev, "panel ID %02x, version: %02x\n",
> + id, version);
> + break;
> + default:
> + DRM_DEV_INFO(acx->dev, "unknown panel ID %02x, version: %02x\n",
> + id, version);
> + break;
> + }
> + acx->version = version;
> +
> + return 0;
> +}
> +
> +static int acx424akp_power_on(struct acx424akp *acx)
> +{
> + int ret;
> +
> + ret = regulator_enable(acx->supply);
> + if (ret) {
> + DRM_DEV_ERROR(acx->dev, "failed to enable supply (%d)\n", ret);
> + return ret;
> + }
> +
> + /* Assert RESET */
> + gpiod_set_value_cansleep(acx->reset_gpio, 1);
> + udelay(20);
> + /* De-assert RESET */
> + gpiod_set_value_cansleep(acx->reset_gpio, 0);
> + msleep(11);
> +
> + return 0;
> +}
> +
> +static int acx424akp_prepare(struct drm_panel *panel)
> +{
> + struct acx424akp *acx = panel_to_acx424akp(panel);
> + struct mipi_dsi_device *dsi = to_mipi_dsi_device(acx->dev);
> + const u8 mddi = 3;
> + int ret;
> +
> + ret = acx424akp_power_on(acx);
> + if (ret)
> + return ret;
> +
> + /* Enabe tearing mode: send TE (tearing effect) at VBLANK */
> + ret = mipi_dsi_dcs_set_tear_on(dsi,
> + MIPI_DSI_DCS_TEAR_MODE_VBLANK);
> + if (ret) {
> + DRM_DEV_ERROR(acx->dev, "failed to enable vblank TE (%d)\n",
> + ret);
> + return ret;
> + }
> +
> + /* Set MDDI */
> + ret = mipi_dsi_dcs_write(dsi, MIPI_DSI_DCS_SET_MDDI,
> + &mddi, sizeof(mddi));
> + if (ret < 0) {
> + DRM_DEV_ERROR(acx->dev, "failed to set MDDI (%d)\n", ret);
> + return ret;
> + }
> +
> + /* Exit sleep mode */
> + ret = mipi_dsi_dcs_exit_sleep_mode(dsi);
> + if (ret) {
> + DRM_DEV_ERROR(acx->dev, "failed to exit sleep mode (%d)\n",
> + ret);
> + return ret;
> + }
> + msleep(140);
> +
> + ret = mipi_dsi_dcs_set_display_on(dsi);
> + if (ret) {
> + DRM_DEV_ERROR(acx->dev, "failed to turn display on (%d)\n",
> + ret);
> + return ret;
> + }
> + if (acx->video_mode) {
> + /* In video mode turn peripheral on */
> + ret = mipi_dsi_turn_on_peripheral(dsi);
> + if (ret) {
> + dev_err(acx->dev, "failed to turn on peripheral\n");
> + return ret;
> + }
> + }
> +
> + acx->bl->props.power = FB_BLANK_NORMAL;
> +
> + return 0;
> +}
> +
> +static void acx424akp_power_off(struct acx424akp *acx)
> +{
> + /* Assert RESET */
> + gpiod_set_value_cansleep(acx->reset_gpio, 1);
> + msleep(11);
> +
> + regulator_disable(acx->supply);
> +}
> +
> +static int acx424akp_unprepare(struct drm_panel *panel)
> +{
> + struct acx424akp *acx = panel_to_acx424akp(panel);
> + struct mipi_dsi_device *dsi = to_mipi_dsi_device(acx->dev);
> + u8 par;
> + int ret;
> +
> + /* Disable backlight */
> + par = 0x00;
> + ret = mipi_dsi_dcs_write(dsi, MIPI_DCS_WRITE_CONTROL_DISPLAY,
> + &par, 1);
> + if (ret) {
> + DRM_DEV_ERROR(acx->dev,
> + "failed to disable display backlight (%d)\n",
> + ret);
> + return ret;
> + }
> +
> + ret = mipi_dsi_dcs_set_display_off(dsi);
> + if (ret) {
> + DRM_DEV_ERROR(acx->dev, "failed to turn display off (%d)\n",
> + ret);
> + return ret;
> + }
> +
> + /* Enter sleep mode */
> + ret = mipi_dsi_dcs_enter_sleep_mode(dsi);
> + if (ret) {
> + DRM_DEV_ERROR(acx->dev, "failed to enter sleep mode (%d)\n",
> + ret);
> + return ret;
> + }
> + msleep(85);
> +
> + acx424akp_power_off(acx);
> + acx->bl->props.power = FB_BLANK_POWERDOWN;
> +
> + return 0;
> +}
> +
> +static int acx424akp_enable(struct drm_panel *panel)
> +{
> + struct acx424akp *acx = panel_to_acx424akp(panel);
> +
> + acx->bl->props.power = FB_BLANK_UNBLANK;
> +
> + return 0;
> +}
> +
> +static int acx424akp_disable(struct drm_panel *panel)
> +{
> + struct acx424akp *acx = panel_to_acx424akp(panel);
> +
> + acx->bl->props.power = FB_BLANK_NORMAL;
> +
> + return 0;
> +}
> +
> +static int acx424akp_get_modes(struct drm_panel *panel)
> +{
> + struct acx424akp *acx = panel_to_acx424akp(panel);
> + struct drm_connector *connector = panel->connector;
> + struct drm_display_mode *mode;
> +
> + if (acx->video_mode)
> + mode = drm_mode_duplicate(panel->drm,
> + &sony_acx424akp_vid_mode);
> + else
> + mode = drm_mode_duplicate(panel->drm,
> + &sony_acx424akp_cmd_mode);
> + if (!mode) {
> + DRM_ERROR("bad mode or failed to add mode\n");
> + return -EINVAL;
> + }
> + 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);
> +
> + return 1; /* Number of modes */
> +}
> +
> +static const struct drm_panel_funcs acx424akp_drm_funcs = {
> + .disable = acx424akp_disable,
> + .unprepare = acx424akp_unprepare,
> + .prepare = acx424akp_prepare,
> + .enable = acx424akp_enable,
> + .get_modes = acx424akp_get_modes,
> +};
> +
> +static int acx424akp_probe(struct mipi_dsi_device *dsi)
> +{
> + struct device *dev = &dsi->dev;
> + struct acx424akp *acx;
> + int ret;
> + unsigned int i;
> +
> + acx = devm_kzalloc(dev, sizeof(struct acx424akp), GFP_KERNEL);
> + if (!acx)
> + return -ENOMEM;
> + acx->video_mode = of_property_read_bool(dev->of_node,
> + "enforce-video-mode");
> +
> + mipi_dsi_set_drvdata(dsi, acx);
> + acx->dev = dev;
> +
> + dsi->lanes = 2;
> + dsi->format = MIPI_DSI_FMT_RGB888;
> + /*
> + * FIXME: these come from the ST-Ericsson vendor driver for the
> + * HREF520 and seems to reflect limitations in the PLLs on that
> + * platform, if you have the datasheet, please cross-check the
> + * actual max rates.
> + */
> + dsi->lp_rate = 19200000;
> + dsi->hs_rate = 420160000;
> +
> + if (acx->video_mode)
> + /* Burst mode using event for sync */
> + dsi->mode_flags =
> + MIPI_DSI_MODE_VIDEO |
> + MIPI_DSI_MODE_VIDEO_BURST;
> + else
> + dsi->mode_flags =
> + MIPI_DSI_CLOCK_NON_CONTINUOUS |
> + MIPI_DSI_MODE_EOT_PACKET;
> +
> + acx->supply = devm_regulator_get(dev, "vddi");
> + if (IS_ERR(acx->supply))
> + return PTR_ERR(acx->supply);
> +
> + /* This asserts RESET by default */
> + acx->reset_gpio = devm_gpiod_get_optional(dev, "reset",
> + GPIOD_OUT_HIGH);
> + if (IS_ERR(acx->reset_gpio)) {
> + ret = PTR_ERR(acx->reset_gpio);
> + if (ret != -EPROBE_DEFER)
> + DRM_DEV_ERROR(dev, "failed to request GPIO (%d)\n",
> + ret);
> + return ret;
> + }
> +
> + drm_panel_init(&acx->panel);
> + acx->panel.dev = dev;
> + acx->panel.funcs = &acx424akp_drm_funcs;
> +
> + acx->bl = devm_backlight_device_register(dev, "acx424akp", dev, acx,
> + &acx424akp_bl_ops, NULL);
> + if (IS_ERR(acx->bl)) {
> + DRM_DEV_ERROR(dev, "failed to register backlight device\n");
> + return PTR_ERR(acx->bl);
> + }
> + acx->bl->props.max_brightness = 1023;
> + acx->bl->props.brightness = 512;
> + acx->bl->props.power = FB_BLANK_POWERDOWN;
> +
> + ret = drm_panel_add(&acx->panel);
> + if (ret < 0)
> + return ret;
> +
> + ret = acx424akp_power_on(acx);
> + if (ret) {
> + DRM_DEV_ERROR(dev, "failed to power up display\n");
> + goto out_remove;
> + }
> +
> + /* Try 5 times to read the device ID */
> + for (i = 0; i < 5; i++) {
> + ret = acx424akp_read_id(acx);
> + if (!ret)
> + break;
> + }
> +
> + if (ret) {
> + DRM_DEV_ERROR(acx->dev, "failed to read panel ID (%d)\n", ret);
> + goto out_poweroff;
> + }
> + acx424akp_power_off(acx);
> +
> + ret = mipi_dsi_attach(dsi);
> + if (ret < 0)
> + goto out_poweroff;
> +
> + return 0;
> +
> +out_poweroff:
> + acx424akp_power_off(acx);
> +out_remove:
> + drm_panel_remove(&acx->panel);
> + return ret;
> +}
> +
> +static int acx424akp_remove(struct mipi_dsi_device *dsi)
> +{
> + struct acx424akp *acx = mipi_dsi_get_drvdata(dsi);
> +
> + mipi_dsi_detach(dsi);
> + drm_panel_remove(&acx->panel);
> +
> + return 0;
> +}
> +
> +static const struct of_device_id acx424akp_of_match[] = {
> + { .compatible = "sony,acx424akp" },
> + { }
> +};
> +MODULE_DEVICE_TABLE(of, acx424akp_of_match);
> +
> +static struct mipi_dsi_driver acx424akp_driver = {
> + .probe = acx424akp_probe,
> + .remove = acx424akp_remove,
> + .driver = {
> + .name = "panel-sony-acx424akp",
> + .of_match_table = acx424akp_of_match,
> + },
> +};
> +module_mipi_dsi_driver(acx424akp_driver);
> +
> +MODULE_AUTHOR("Linus Wallei <linus.wall...@linaro.org>");
> +MODULE_DESCRIPTION("MIPI-DSI Sony acx424akp Panel Driver");
> +MODULE_LICENSE("GPL v2");
> diff --git a/include/video/mipi_display.h b/include/video/mipi_display.h
> index cba57a678daf..cf99c6a519d5 100644
> --- a/include/video/mipi_display.h
> +++ b/include/video/mipi_display.h
> @@ -125,6 +125,7 @@ enum {
> MIPI_DCS_GET_CABC_MIN_BRIGHTNESS = 0x5F, /* MIPI DCS 1.3 */
> MIPI_DCS_READ_DDB_START = 0xA1,
> MIPI_DCS_READ_DDB_CONTINUE = 0xA8,
> + MIPI_DSI_DCS_SET_MDDI = 0xAE,
> };
>
> /* MIPI DCS pixel formats */
> --
> 2.21.0
>
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