Re: [PATCH v1 2/2] drm:bridge: Add Lontiun LT7911EXC eDP to MIPI DSI bridge
From: 杨孙运
Date: Tue Apr 28 2026 - 04:19:35 EST
Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxxxxxxxx> 于2026年4月28日周二 15:49写道:
>
> On Tue, Apr 28, 2026 at 02:32:24PM +0800, syyang@xxxxxxxxxxx wrote:
> > From: Sunyun Yang <syyang@xxxxxxxxxxx>
> >
> > The LT7911EXC is an I2C-controlled bridge that Receiver eDP1.4
> > and output signal/dual port mipi.
> >
> > Signed-off-by: Sunyun Yang <syyang@xxxxxxxxxxx>
> > ---
> > drivers/gpu/drm/bridge/Kconfig | 13 +
> > drivers/gpu/drm/bridge/Makefile | 1 +
> > drivers/gpu/drm/bridge/lontium-lt7911exc.c | 497 +++++++++++++++++++++
> > 3 files changed, 511 insertions(+)
> > create mode 100644 drivers/gpu/drm/bridge/lontium-lt7911exc.c
> >
> > diff --git a/drivers/gpu/drm/bridge/Kconfig b/drivers/gpu/drm/bridge/Kconfig
> > index c3209b0f4678..8cff2bf15b09 100644
> > --- a/drivers/gpu/drm/bridge/Kconfig
> > +++ b/drivers/gpu/drm/bridge/Kconfig
> > @@ -132,6 +132,19 @@ config DRM_ITE_IT6505
> > help
> > ITE IT6505 DisplayPort bridge chip driver.
> >
> > +config DRM_LONTIUM_LT7911EXC
> > + tristate "Lontium eDP/MIPI bridge"
> > + depends on OF
> > + select CRC32
> > + select FW_LOADER
> > + select DRM_PANEL
> > + select DRM_KMS_HELPER
> > + help
> > + DRM driver for the Lontium LT7911EXC bridge chip.
> > + The LT7911EXC converts eDP input to single/dual port
> > + MIPI DSI output.
> > + Please say Y if you have such hardware.
> > +
> > config DRM_LONTIUM_LT8912B
> > tristate "Lontium LT8912B DSI/HDMI bridge"
> > depends on OF
> > diff --git a/drivers/gpu/drm/bridge/Makefile b/drivers/gpu/drm/bridge/Makefile
> > index beab5b695a6e..70ddca75dd3a 100644
> > --- a/drivers/gpu/drm/bridge/Makefile
> > +++ b/drivers/gpu/drm/bridge/Makefile
> > @@ -13,6 +13,7 @@ obj-$(CONFIG_DRM_I2C_NXP_TDA998X) += tda998x.o
> > obj-$(CONFIG_DRM_INNO_HDMI) += inno-hdmi.o
> > obj-$(CONFIG_DRM_ITE_IT6263) += ite-it6263.o
> > obj-$(CONFIG_DRM_ITE_IT6505) += ite-it6505.o
> > +obj-$(CONFIG_DRM_LONTIUM_LT7911EXC) += lontium-lt7911exc.o
> > obj-$(CONFIG_DRM_LONTIUM_LT8912B) += lontium-lt8912b.o
> > obj-$(CONFIG_DRM_LONTIUM_LT9211) += lontium-lt9211.o
> > obj-$(CONFIG_DRM_LONTIUM_LT9611) += lontium-lt9611.o
> > diff --git a/drivers/gpu/drm/bridge/lontium-lt7911exc.c b/drivers/gpu/drm/bridge/lontium-lt7911exc.c
> > new file mode 100644
> > index 000000000000..85cb6cedbfa3
> > --- /dev/null
> > +++ b/drivers/gpu/drm/bridge/lontium-lt7911exc.c
> > @@ -0,0 +1,497 @@
> > +// SPDX-License-Identifier: GPL-2.0
> > +/*
> > + * Copyright (C) 2026 Lontium Semiconductor, Inc.
> > + */
> > +
> > +#include <linux/crc32.h>
> > +#include <linux/firmware.h>
> > +#include <linux/gpio/consumer.h>
> > +#include <linux/i2c.h>
> > +#include <linux/module.h>
> > +#include <linux/mutex.h>
> > +#include <linux/of_graph.h>
> > +#include <linux/platform_device.h>
> > +#include <linux/regmap.h>
> > +
> > +#include <drm/drm_bridge.h>
> > +#include <drm/drm_mipi_dsi.h>
> > +#include <drm/drm_of.h>
> > +
> > +#define FW_SIZE (64 * 1024)
> > +#define LT_PAGE_SIZE 32
> > +#define FW_FILE "lt7911exc_fw.bin"
>
> Do you plan to submit the referene image to linux-firmware?
>
I want to submit it, but I don't know how. Please help me.
> > +#define LT7911EXC_PAGE_CONTROL 0xff
> > +
>
> [...]
>
> > +
> > +static void lt7911exc_remove(struct i2c_client *client)
> > +{}
>
> If it's empty, it should be dropped. .remove is an optional callback.
>
it will be fixed in next version.
> > +
> > +static const struct i2c_device_id lt7911exc_i2c_table[] = {
> > + {"lontium, lt7911exc"},
>
> Drop the "lontium, " part. The I2C ids (unlike OF ids) don't have the
> vendor part.
>
it will be fixed in next version.
> > + {/* sentinel */}
> > +};
> > +
> > +MODULE_DEVICE_TABLE(i2c, lt7911exc_i2c_table);
> > +
>
> --
> With best wishes
> Dmitry