| Message ID | 20220125175700.37408-4-noralf@tronnes.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | drm/panel: Add MIPI DBI compatible SPI driver | expand |
On Tue, Jan 25, 2022 at 06:57:00PM +0100, Noralf Trønnes wrote: > Add a driver that will work with most MIPI DBI compatible SPI panels. > This avoids adding a driver for every new MIPI DBI compatible controller > that is to be used by Linux. The 'compatible' Device Tree property with > a '.bin' suffix will be used to load a firmware file that contains the > controller configuration. > > Example (driver will load sainsmart18.bin): > > display@0 { > compatible = "sainsmart18", "panel-mipi-dbi-spi"; > reg = <0>; > reset-gpios = <&gpio 25 0>; > dc-gpios = <&gpio 24 0>; > }; > > v2: > - Drop model property and use compatible instead (Rob) > - Add wiki entry in MAINTAINERS > > Signed-off-by: Noralf Trønnes <noralf@tronnes.org> > --- > MAINTAINERS | 8 + > drivers/gpu/drm/panel/Kconfig | 11 + > drivers/gpu/drm/panel/Makefile | 1 + > drivers/gpu/drm/panel/panel-mipi-dbi.c | 394 +++++++++++++++++++++++++ > 4 files changed, 414 insertions(+) > create mode 100644 drivers/gpu/drm/panel/panel-mipi-dbi.c > > diff --git a/MAINTAINERS b/MAINTAINERS > index d03ad8da1f36..8baa98723bdc 100644 > --- a/MAINTAINERS > +++ b/MAINTAINERS > @@ -6047,6 +6047,14 @@ T: git git://anongit.freedesktop.org/drm/drm-misc > F: Documentation/devicetree/bindings/display/multi-inno,mi0283qt.txt > F: drivers/gpu/drm/tiny/mi0283qt.c > > +DRM DRIVER FOR MIPI DBI compatible panels > +M: Noralf Trønnes <noralf@tronnes.org> > +S: Maintained > +W: https://github.com/notro/panel-mipi-dbi/wiki > +T: git git://anongit.freedesktop.org/drm/drm-misc > +F: Documentation/devicetree/bindings/display/panel/panel-mipi-dbi-spi.yaml > +F: drivers/gpu/drm/panel/panel-mipi-dbi.c > + > DRM DRIVER FOR MSM ADRENO GPU > M: Rob Clark <robdclark@gmail.com> > M: Sean Paul <sean@poorly.run> > diff --git a/drivers/gpu/drm/panel/Kconfig b/drivers/gpu/drm/panel/Kconfig > index 434c2861bb40..1851cda5f877 100644 > --- a/drivers/gpu/drm/panel/Kconfig > +++ b/drivers/gpu/drm/panel/Kconfig > @@ -274,6 +274,17 @@ config DRM_PANEL_LG_LG4573 > Say Y here if you want to enable support for LG4573 RGB panel. > To compile this driver as a module, choose M here. > > +config DRM_PANEL_MIPI_DBI > + tristate "MIPI DBI compatible panel" > + depends on SPI > + depends on BACKLIGHT_CLASS_DEVICE > + depends on DRM_KMS_HELPER > + select DRM_KMS_CMA_HELPER > + select DRM_MIPI_DBI > + help > + Say Y here if you want to enable support for MIPI DBI compatible panels. > + To compile this driver as a module, choose M here. > + > config DRM_PANEL_NEC_NL8048HL11 > tristate "NEC NL8048HL11 RGB panel" > depends on GPIOLIB && OF && SPI > diff --git a/drivers/gpu/drm/panel/Makefile b/drivers/gpu/drm/panel/Makefile > index d99fbbce49d1..a90c30459964 100644 > --- a/drivers/gpu/drm/panel/Makefile > +++ b/drivers/gpu/drm/panel/Makefile > @@ -25,6 +25,7 @@ obj-$(CONFIG_DRM_PANEL_LEADTEK_LTK050H3146W) += panel-leadtek-ltk050h3146w.o > obj-$(CONFIG_DRM_PANEL_LEADTEK_LTK500HD1829) += panel-leadtek-ltk500hd1829.o > obj-$(CONFIG_DRM_PANEL_LG_LB035Q02) += panel-lg-lb035q02.o > obj-$(CONFIG_DRM_PANEL_LG_LG4573) += panel-lg-lg4573.o > +obj-$(CONFIG_DRM_PANEL_MIPI_DBI) += panel-mipi-dbi.o > obj-$(CONFIG_DRM_PANEL_NEC_NL8048HL11) += panel-nec-nl8048hl11.o > obj-$(CONFIG_DRM_PANEL_NOVATEK_NT35510) += panel-novatek-nt35510.o > obj-$(CONFIG_DRM_PANEL_NOVATEK_NT35950) += panel-novatek-nt35950.o > diff --git a/drivers/gpu/drm/panel/panel-mipi-dbi.c b/drivers/gpu/drm/panel/panel-mipi-dbi.c > new file mode 100644 > index 000000000000..6e3dc2de21d2 > --- /dev/null > +++ b/drivers/gpu/drm/panel/panel-mipi-dbi.c > @@ -0,0 +1,394 @@ > +// SPDX-License-Identifier: GPL-2.0 > +/* > + * DRM driver for MIPI DBI compatible display panels > + * > + * Copyright 2022 Noralf Trønnes > + */ > + > +#include <linux/backlight.h> > +#include <linux/delay.h> > +#include <linux/firmware.h> > +#include <linux/gpio/consumer.h> > +#include <linux/module.h> > +#include <linux/property.h> > +#include <linux/regulator/consumer.h> > +#include <linux/spi/spi.h> > + > +#include <drm/drm_atomic_helper.h> > +#include <drm/drm_drv.h> > +#include <drm/drm_fb_helper.h> > +#include <drm/drm_gem_atomic_helper.h> > +#include <drm/drm_gem_cma_helper.h> > +#include <drm/drm_managed.h> > +#include <drm/drm_mipi_dbi.h> > +#include <drm/drm_modeset_helper.h> > +#include <video/mipi_display.h> > + > +static const u8 panel_mipi_dbi_magic[15] = { 'M', 'I', 'P', 'I', ' ', 'D', 'B', 'I', > + 0, 0, 0, 0, 0, 0, 0 }; > + > +/* > + * The display panel configuration is stored in a firmware file. The Device Tree 'compatible' > + * property value with a '.bin' suffix is passed to request_firmware() to fetch this file. > + */ > +struct panel_mipi_dbi_config { > + /* Magic string: panel_mipi_dbi_magic */ > + u8 magic[15]; > + > + /* Config file format version */ > + u8 file_format_version; > + > + /* Width in pixels */ > + __be16 width; > + /* Height in pixels */ > + __be16 height; > + > + /* Width in millimeters (optional) */ > + __be16 width_mm; > + /* Height in millimeters (optional) */ > + __be16 height_mm; > + > + /* X-axis panel offset */ > + __be16 x_offset; > + /* Y-axis panel offset */ > + __be16 y_offset; > + > + /* 4 pad bytes, must be zero */ > + u8 pad[4]; > + > + /* > + * Optional MIPI commands to execute when the display pipeline is enabled. > + * This can be used to configure the display controller. > + * > + * The commands are stored in a byte array with the format: > + * command, num_parameters, [ parameter, ...], command, ... > + * > + * Some commands require a pause before the next command can be received. > + * Inserting a delay in the command sequence is done by using the NOP command with one > + * parameter: delay in miliseconds (the No Operation command is part of the MIPI Display > + * Command Set where it has no parameters). > + * > + * Example: > + * command 0x11 > + * sleep 120ms > + * command 0xb1 parameters 0x01, 0x2c, 0x2d > + * command 0x29 > + * > + * Byte sequence: > + * 0x11 0x00 > + * 0x00 0x01 0x78 > + * 0xb1 0x03 0x01 0x2c 0x2d > + * 0x29 0x00 > + */ > + u8 commands[]; > +}; I'm not really a fan of parsing raw data in the kernel. I guess we can't really avoid the introduction of a special case to sleep, but we already have dt properties for all of the other properties (but X and Y offset, maybe?) Maybe we should use those instead? Maxime
On 1/25/22 11:57 AM, Noralf Trønnes wrote: > Add a driver that will work with most MIPI DBI compatible SPI panels. > This avoids adding a driver for every new MIPI DBI compatible controller > that is to be used by Linux. The 'compatible' Device Tree property with > a '.bin' suffix will be used to load a firmware file that contains the > controller configuration. > > Example (driver will load sainsmart18.bin): > > display@0 { > compatible = "sainsmart18", "panel-mipi-dbi-spi"; > reg = <0>; > reset-gpios = <&gpio 25 0>; > dc-gpios = <&gpio 24 0>; > }; > ... > +static int panel_mipi_dbi_spi_probe(struct spi_device *spi) > +{ > + struct device *dev = &spi->dev; > + struct drm_display_mode mode; > + struct mipi_dbi_dev *dbidev; > + const struct firmware *fw; > + const char *compatible; > + struct drm_device *drm; > + struct property *prop; > + bool fw_found = false; > + struct mipi_dbi *dbi; > + struct gpio_desc *dc; > + char fw_name[40]; > + int ret; > + > + dbidev = devm_drm_dev_alloc(dev, &panel_mipi_dbi_driver, struct mipi_dbi_dev, drm); > + if (IS_ERR(dbidev)) > + return PTR_ERR(dbidev); > + > + dbi = &dbidev->dbi; > + drm = &dbidev->drm; > + > + of_property_for_each_string(dev->of_node, "compatible", prop, compatible) { > + snprintf(fw_name, sizeof(fw_name), "%s.bin", compatible); > + > + ret = firmware_request_nowarn(&fw, fw_name, dev); > + if (ret) { > + drm_dbg(drm, "No config file found for compatible: '%s' (error=%d)\n", > + compatible, ret); > + continue; > + } > + Should we add a directory prefix to the firmware file name to avoid the possibility of file name clashes with unrelated firmwares?
Den 27.01.2022 11.04, skrev Maxime Ripard: > On Tue, Jan 25, 2022 at 06:57:00PM +0100, Noralf Trønnes wrote: >> Add a driver that will work with most MIPI DBI compatible SPI panels. >> This avoids adding a driver for every new MIPI DBI compatible controller >> that is to be used by Linux. The 'compatible' Device Tree property with >> a '.bin' suffix will be used to load a firmware file that contains the >> controller configuration. >> >> Example (driver will load sainsmart18.bin): >> >> display@0 { >> compatible = "sainsmart18", "panel-mipi-dbi-spi"; >> reg = <0>; >> reset-gpios = <&gpio 25 0>; >> dc-gpios = <&gpio 24 0>; >> }; >> >> v2: >> - Drop model property and use compatible instead (Rob) >> - Add wiki entry in MAINTAINERS >> >> Signed-off-by: Noralf Trønnes <noralf@tronnes.org> >> --- >> MAINTAINERS | 8 + >> drivers/gpu/drm/panel/Kconfig | 11 + >> drivers/gpu/drm/panel/Makefile | 1 + >> drivers/gpu/drm/panel/panel-mipi-dbi.c | 394 +++++++++++++++++++++++++ >> 4 files changed, 414 insertions(+) >> create mode 100644 drivers/gpu/drm/panel/panel-mipi-dbi.c >> >> diff --git a/MAINTAINERS b/MAINTAINERS >> index d03ad8da1f36..8baa98723bdc 100644 >> --- a/MAINTAINERS >> +++ b/MAINTAINERS >> @@ -6047,6 +6047,14 @@ T: git git://anongit.freedesktop.org/drm/drm-misc >> F: Documentation/devicetree/bindings/display/multi-inno,mi0283qt.txt >> F: drivers/gpu/drm/tiny/mi0283qt.c >> >> +DRM DRIVER FOR MIPI DBI compatible panels >> +M: Noralf Trønnes <noralf@tronnes.org> >> +S: Maintained >> +W: https://github.com/notro/panel-mipi-dbi/wiki >> +T: git git://anongit.freedesktop.org/drm/drm-misc >> +F: Documentation/devicetree/bindings/display/panel/panel-mipi-dbi-spi.yaml >> +F: drivers/gpu/drm/panel/panel-mipi-dbi.c >> + >> DRM DRIVER FOR MSM ADRENO GPU >> M: Rob Clark <robdclark@gmail.com> >> M: Sean Paul <sean@poorly.run> >> diff --git a/drivers/gpu/drm/panel/Kconfig b/drivers/gpu/drm/panel/Kconfig >> index 434c2861bb40..1851cda5f877 100644 >> --- a/drivers/gpu/drm/panel/Kconfig >> +++ b/drivers/gpu/drm/panel/Kconfig >> @@ -274,6 +274,17 @@ config DRM_PANEL_LG_LG4573 >> Say Y here if you want to enable support for LG4573 RGB panel. >> To compile this driver as a module, choose M here. >> >> +config DRM_PANEL_MIPI_DBI >> + tristate "MIPI DBI compatible panel" >> + depends on SPI >> + depends on BACKLIGHT_CLASS_DEVICE >> + depends on DRM_KMS_HELPER >> + select DRM_KMS_CMA_HELPER >> + select DRM_MIPI_DBI >> + help >> + Say Y here if you want to enable support for MIPI DBI compatible panels. >> + To compile this driver as a module, choose M here. >> + >> config DRM_PANEL_NEC_NL8048HL11 >> tristate "NEC NL8048HL11 RGB panel" >> depends on GPIOLIB && OF && SPI >> diff --git a/drivers/gpu/drm/panel/Makefile b/drivers/gpu/drm/panel/Makefile >> index d99fbbce49d1..a90c30459964 100644 >> --- a/drivers/gpu/drm/panel/Makefile >> +++ b/drivers/gpu/drm/panel/Makefile >> @@ -25,6 +25,7 @@ obj-$(CONFIG_DRM_PANEL_LEADTEK_LTK050H3146W) += panel-leadtek-ltk050h3146w.o >> obj-$(CONFIG_DRM_PANEL_LEADTEK_LTK500HD1829) += panel-leadtek-ltk500hd1829.o >> obj-$(CONFIG_DRM_PANEL_LG_LB035Q02) += panel-lg-lb035q02.o >> obj-$(CONFIG_DRM_PANEL_LG_LG4573) += panel-lg-lg4573.o >> +obj-$(CONFIG_DRM_PANEL_MIPI_DBI) += panel-mipi-dbi.o >> obj-$(CONFIG_DRM_PANEL_NEC_NL8048HL11) += panel-nec-nl8048hl11.o >> obj-$(CONFIG_DRM_PANEL_NOVATEK_NT35510) += panel-novatek-nt35510.o >> obj-$(CONFIG_DRM_PANEL_NOVATEK_NT35950) += panel-novatek-nt35950.o >> diff --git a/drivers/gpu/drm/panel/panel-mipi-dbi.c b/drivers/gpu/drm/panel/panel-mipi-dbi.c >> new file mode 100644 >> index 000000000000..6e3dc2de21d2 >> --- /dev/null >> +++ b/drivers/gpu/drm/panel/panel-mipi-dbi.c >> @@ -0,0 +1,394 @@ >> +// SPDX-License-Identifier: GPL-2.0 >> +/* >> + * DRM driver for MIPI DBI compatible display panels >> + * >> + * Copyright 2022 Noralf Trønnes >> + */ >> + >> +#include <linux/backlight.h> >> +#include <linux/delay.h> >> +#include <linux/firmware.h> >> +#include <linux/gpio/consumer.h> >> +#include <linux/module.h> >> +#include <linux/property.h> >> +#include <linux/regulator/consumer.h> >> +#include <linux/spi/spi.h> >> + >> +#include <drm/drm_atomic_helper.h> >> +#include <drm/drm_drv.h> >> +#include <drm/drm_fb_helper.h> >> +#include <drm/drm_gem_atomic_helper.h> >> +#include <drm/drm_gem_cma_helper.h> >> +#include <drm/drm_managed.h> >> +#include <drm/drm_mipi_dbi.h> >> +#include <drm/drm_modeset_helper.h> >> +#include <video/mipi_display.h> >> + >> +static const u8 panel_mipi_dbi_magic[15] = { 'M', 'I', 'P', 'I', ' ', 'D', 'B', 'I', >> + 0, 0, 0, 0, 0, 0, 0 }; >> + >> +/* >> + * The display panel configuration is stored in a firmware file. The Device Tree 'compatible' >> + * property value with a '.bin' suffix is passed to request_firmware() to fetch this file. >> + */ >> +struct panel_mipi_dbi_config { >> + /* Magic string: panel_mipi_dbi_magic */ >> + u8 magic[15]; >> + >> + /* Config file format version */ >> + u8 file_format_version; >> + >> + /* Width in pixels */ >> + __be16 width; >> + /* Height in pixels */ >> + __be16 height; >> + >> + /* Width in millimeters (optional) */ >> + __be16 width_mm; >> + /* Height in millimeters (optional) */ >> + __be16 height_mm; >> + >> + /* X-axis panel offset */ >> + __be16 x_offset; >> + /* Y-axis panel offset */ >> + __be16 y_offset; >> + >> + /* 4 pad bytes, must be zero */ >> + u8 pad[4]; >> + >> + /* >> + * Optional MIPI commands to execute when the display pipeline is enabled. >> + * This can be used to configure the display controller. >> + * >> + * The commands are stored in a byte array with the format: >> + * command, num_parameters, [ parameter, ...], command, ... >> + * >> + * Some commands require a pause before the next command can be received. >> + * Inserting a delay in the command sequence is done by using the NOP command with one >> + * parameter: delay in miliseconds (the No Operation command is part of the MIPI Display >> + * Command Set where it has no parameters). >> + * >> + * Example: >> + * command 0x11 >> + * sleep 120ms >> + * command 0xb1 parameters 0x01, 0x2c, 0x2d >> + * command 0x29 >> + * >> + * Byte sequence: >> + * 0x11 0x00 >> + * 0x00 0x01 0x78 >> + * 0xb1 0x03 0x01 0x2c 0x2d >> + * 0x29 0x00 >> + */ >> + u8 commands[]; >> +}; > > I'm not really a fan of parsing raw data in the kernel. I guess we can't > really avoid the introduction of a special case to sleep, but we already > have dt properties for all of the other properties (but X and Y offset, > maybe?) > > Maybe we should use those instead? > I don't understand your reluctance to parsing data, lots of ioctls do it. And this data can only be loaded by root. What I like about having these properties in the config file is that the binding becomes a fallback binding that can actually be made to work without changing the Device Tree. For arguments sake let's say tiny/st7735r.c was not built and we had this node: display@0{ compatible = "jianda,jd-t18003-t01", "sitronix,st7735r", "panel-mipi-dbi-spi"; }; It will still be possible to use this display without changing the Device Tree. Just add a firmware/config file. Having the properties in DT it would have to look like this for the fallback to work: display@0{ compatible = "jianda,jd-t18003-t01", "sitronix,st7735r", "panel-mipi-dbi-spi"; panel-timing = { hactive = <128>; vactive = <128>; }; width-mm = <25>; height-mm = <26>; x-offset = <2>; y-offset = <3>; }; Is this important, I'm not sure. What do you think? The users I care most about have DT overlays so for them it doesn't matter much where the properties are. Noralf.
Hi Noralf, On Tue, Jan 25, 2022 at 06:57:00PM +0100, Noralf Trønnes wrote: > Add a driver that will work with most MIPI DBI compatible SPI panels. > This avoids adding a driver for every new MIPI DBI compatible controller > that is to be used by Linux. The 'compatible' Device Tree property with > a '.bin' suffix will be used to load a firmware file that contains the > controller configuration. Loading a configuration from a firmware file is very elegant - I like. This will be very useful in a million cases with a lot of small panels! > + > + /* > + * Optional MIPI commands to execute when the display pipeline is enabled. > + * This can be used to configure the display controller. > + * > + * The commands are stored in a byte array with the format: > + * command, num_parameters, [ parameter, ...], command, ... > + * > + * Some commands require a pause before the next command can be received. > + * Inserting a delay in the command sequence is done by using the NOP command with one > + * parameter: delay in miliseconds (the No Operation command is part of the MIPI Display > + * Command Set where it has no parameters). > + * > + * Example: > + * command 0x11 > + * sleep 120ms > + * command 0xb1 parameters 0x01, 0x2c, 0x2d > + * command 0x29 > + * > + * Byte sequence: > + * 0x11 0x00 > + * 0x00 0x01 0x78 > + * 0xb1 0x03 0x01 0x2c 0x2d > + * 0x29 0x00 > + */ Using a binary file that is unreadable when it is first created is less elegant. I am sure you have considered a txt file - and I know parsing a txt file in prone for more errros than parsing a binary file. But if the text file looked like: " # The is a comment cmd 0x11 0x00 # We need to sleep sleepms 120 # Do something more cmd 0xb1 0x03 0x01 0x2c 0x2d cmd 0x29 0x00 " The file is easier to comment (document) and easier to read and modify. The suffix could be ".panel" to tell this is something specific for a panel. Using lib/parser could make the code somewhat simple but I did not try to code it myself. The code you included below for the binary file is very simple, but you shift the burden to the people who have to create binary files. And people using obscure displays are not always so good at this stuff. Sorry that I do not include code to do the above, but let me know if this would help to convince you. Sam - who has been absent due to house renovation and such
Den 27.01.2022 18.19, skrev David Lechner: > On 1/25/22 11:57 AM, Noralf Trønnes wrote: >> Add a driver that will work with most MIPI DBI compatible SPI panels. >> This avoids adding a driver for every new MIPI DBI compatible controller >> that is to be used by Linux. The 'compatible' Device Tree property with >> a '.bin' suffix will be used to load a firmware file that contains the >> controller configuration. >> >> Example (driver will load sainsmart18.bin): >> >> display@0 { >> compatible = "sainsmart18", "panel-mipi-dbi-spi"; >> reg = <0>; >> reset-gpios = <&gpio 25 0>; >> dc-gpios = <&gpio 24 0>; >> }; >> > > ... > >> +static int panel_mipi_dbi_spi_probe(struct spi_device *spi) >> +{ >> + struct device *dev = &spi->dev; >> + struct drm_display_mode mode; >> + struct mipi_dbi_dev *dbidev; >> + const struct firmware *fw; >> + const char *compatible; >> + struct drm_device *drm; >> + struct property *prop; >> + bool fw_found = false; >> + struct mipi_dbi *dbi; >> + struct gpio_desc *dc; >> + char fw_name[40]; >> + int ret; >> + >> + dbidev = devm_drm_dev_alloc(dev, &panel_mipi_dbi_driver, struct >> mipi_dbi_dev, drm); >> + if (IS_ERR(dbidev)) >> + return PTR_ERR(dbidev); >> + >> + dbi = &dbidev->dbi; >> + drm = &dbidev->drm; >> + >> + of_property_for_each_string(dev->of_node, "compatible", prop, >> compatible) { >> + snprintf(fw_name, sizeof(fw_name), "%s.bin", compatible); >> + >> + ret = firmware_request_nowarn(&fw, fw_name, dev); >> + if (ret) { >> + drm_dbg(drm, "No config file found for compatible: '%s' >> (error=%d)\n", >> + compatible, ret); >> + continue; >> + } >> + > > Should we add a directory prefix to the firmware file name to avoid the > possibility of > file name clashes with unrelated firmwares? I did consider this but I think it very unlikely that there would be a collision between the name of display/panel and some other firmware file which usually have the product name/model in the filename. And in the unlikelihood that there is a collision it's possible to choose another name for the compatible. Noralf.
Den 27.01.2022 20.59, skrev Sam Ravnborg: > Hi Noralf, > > On Tue, Jan 25, 2022 at 06:57:00PM +0100, Noralf Trønnes wrote: >> Add a driver that will work with most MIPI DBI compatible SPI panels. >> This avoids adding a driver for every new MIPI DBI compatible controller >> that is to be used by Linux. The 'compatible' Device Tree property with >> a '.bin' suffix will be used to load a firmware file that contains the >> controller configuration. > > Loading a configuration from a firmware file is very > elegant - I like. > This will be very useful in a million cases with a lot of small panels! > Yes I really hope we can find a way to get this accepted. >> + >> + /* >> + * Optional MIPI commands to execute when the display pipeline is enabled. >> + * This can be used to configure the display controller. >> + * >> + * The commands are stored in a byte array with the format: >> + * command, num_parameters, [ parameter, ...], command, ... >> + * >> + * Some commands require a pause before the next command can be received. >> + * Inserting a delay in the command sequence is done by using the NOP command with one >> + * parameter: delay in miliseconds (the No Operation command is part of the MIPI Display >> + * Command Set where it has no parameters). >> + * >> + * Example: >> + * command 0x11 >> + * sleep 120ms >> + * command 0xb1 parameters 0x01, 0x2c, 0x2d >> + * command 0x29 >> + * >> + * Byte sequence: >> + * 0x11 0x00 >> + * 0x00 0x01 0x78 >> + * 0xb1 0x03 0x01 0x2c 0x2d >> + * 0x29 0x00 >> + */ > Using a binary file that is unreadable when it is first created is less > elegant. > I am sure you have considered a txt file - and I know parsing a txt file > in prone for more errros than parsing a binary file. > > > But if the text file looked like: > " > # The is a comment > cmd 0x11 0x00 > > # We need to sleep > sleepms 120 > > # Do something more > cmd 0xb1 0x03 0x01 0x2c 0x2d > cmd 0x29 0x00 > " > > The file is easier to comment (document) and easier to read and > modify. > The suffix could be ".panel" to tell this is something specific for > a panel. > Using lib/parser could make the code somewhat simple but I did not try > to code it myself. > > The code you included below for the binary file is very simple, > but you shift the burden to the people who have to create binary files. > And people using obscure displays are not always so good at this stuff. > Parsing text files in the kernel sounds very scary, not something that I would like to try. I will make a script that generates and parses the binary representation (which is big endian so it's somewhat readable with xxd or the like). There's a wiki link in the MAINTAINERS entry that will have info about the format including the script. It will also serve as a place to share config snippets/script incantations for displays. I will make the script when the file format is decided upon. Here's the hack I currently use: https://gist.github.com/notro/3ca61c48e7dcc4a0ef34dbadbc30bfa5 Noralf.
On Thu, Jan 27, 2022 at 06:53:48PM +0100, Noralf Trønnes wrote: > >> +struct panel_mipi_dbi_config { > >> + /* Magic string: panel_mipi_dbi_magic */ > >> + u8 magic[15]; > >> + > >> + /* Config file format version */ > >> + u8 file_format_version; > >> + > >> + /* Width in pixels */ > >> + __be16 width; > >> + /* Height in pixels */ > >> + __be16 height; > >> + > >> + /* Width in millimeters (optional) */ > >> + __be16 width_mm; > >> + /* Height in millimeters (optional) */ > >> + __be16 height_mm; > >> + > >> + /* X-axis panel offset */ > >> + __be16 x_offset; > >> + /* Y-axis panel offset */ > >> + __be16 y_offset; > >> + > >> + /* 4 pad bytes, must be zero */ > >> + u8 pad[4]; > >> + > >> + /* > >> + * Optional MIPI commands to execute when the display pipeline is enabled. > >> + * This can be used to configure the display controller. > >> + * > >> + * The commands are stored in a byte array with the format: > >> + * command, num_parameters, [ parameter, ...], command, ... > >> + * > >> + * Some commands require a pause before the next command can be received. > >> + * Inserting a delay in the command sequence is done by using the NOP command with one > >> + * parameter: delay in miliseconds (the No Operation command is part of the MIPI Display > >> + * Command Set where it has no parameters). > >> + * > >> + * Example: > >> + * command 0x11 > >> + * sleep 120ms > >> + * command 0xb1 parameters 0x01, 0x2c, 0x2d > >> + * command 0x29 > >> + * > >> + * Byte sequence: > >> + * 0x11 0x00 > >> + * 0x00 0x01 0x78 > >> + * 0xb1 0x03 0x01 0x2c 0x2d > >> + * 0x29 0x00 > >> + */ > >> + u8 commands[]; > >> +}; > > > > I'm not really a fan of parsing raw data in the kernel. I guess we can't > > really avoid the introduction of a special case to sleep, but we already > > have dt properties for all of the other properties (but X and Y offset, > > maybe?) > > > > Maybe we should use those instead? > > I don't understand your reluctance to parsing data, lots of ioctls do > it. The reluctance comes from the parsing itself: you need to have input validation, and it's hard to get right. The less we have, the easier it gets. > And this data can only be loaded by root. What I like about having > these properties in the config file is that the binding becomes a > fallback binding that can actually be made to work without changing the > Device Tree. > > For arguments sake let's say tiny/st7735r.c was not built and we had > this node: > > display@0{ > compatible = "jianda,jd-t18003-t01", "sitronix,st7735r", > "panel-mipi-dbi-spi"; > }; > > It will still be possible to use this display without changing the > Device Tree. Just add a firmware/config file. > > Having the properties in DT it would have to look like this for the > fallback to work: > > display@0{ > compatible = "jianda,jd-t18003-t01", "sitronix,st7735r", > "panel-mipi-dbi-spi"; > panel-timing = { > hactive = <128>; > vactive = <128>; > }; > width-mm = <25>; > height-mm = <26>; > x-offset = <2>; > y-offset = <3>; > }; > > Is this important, I'm not sure. What do you think? Parts of it is ergonomics I guess. We're used to having all those properties either in the DT or the driver, but here we introduce a new way that isn't done anywhere else. And I don't see any real downside to putting it in the DT? It's going to be in an overlay, under the user's control anyway, right? Maxime
Den 02.02.2022 11.09, skrev Maxime Ripard: > On Thu, Jan 27, 2022 at 06:53:48PM +0100, Noralf Trønnes wrote: >>>> +struct panel_mipi_dbi_config { >>>> + /* Magic string: panel_mipi_dbi_magic */ >>>> + u8 magic[15]; >>>> + >>>> + /* Config file format version */ >>>> + u8 file_format_version; >>>> + >>>> + /* Width in pixels */ >>>> + __be16 width; >>>> + /* Height in pixels */ >>>> + __be16 height; >>>> + >>>> + /* Width in millimeters (optional) */ >>>> + __be16 width_mm; >>>> + /* Height in millimeters (optional) */ >>>> + __be16 height_mm; >>>> + >>>> + /* X-axis panel offset */ >>>> + __be16 x_offset; >>>> + /* Y-axis panel offset */ >>>> + __be16 y_offset; >>>> + >>>> + /* 4 pad bytes, must be zero */ >>>> + u8 pad[4]; >>>> + >>>> + /* >>>> + * Optional MIPI commands to execute when the display pipeline is enabled. >>>> + * This can be used to configure the display controller. >>>> + * >>>> + * The commands are stored in a byte array with the format: >>>> + * command, num_parameters, [ parameter, ...], command, ... >>>> + * >>>> + * Some commands require a pause before the next command can be received. >>>> + * Inserting a delay in the command sequence is done by using the NOP command with one >>>> + * parameter: delay in miliseconds (the No Operation command is part of the MIPI Display >>>> + * Command Set where it has no parameters). >>>> + * >>>> + * Example: >>>> + * command 0x11 >>>> + * sleep 120ms >>>> + * command 0xb1 parameters 0x01, 0x2c, 0x2d >>>> + * command 0x29 >>>> + * >>>> + * Byte sequence: >>>> + * 0x11 0x00 >>>> + * 0x00 0x01 0x78 >>>> + * 0xb1 0x03 0x01 0x2c 0x2d >>>> + * 0x29 0x00 >>>> + */ >>>> + u8 commands[]; >>>> +}; >>> >>> I'm not really a fan of parsing raw data in the kernel. I guess we can't >>> really avoid the introduction of a special case to sleep, but we already >>> have dt properties for all of the other properties (but X and Y offset, >>> maybe?) >>> >>> Maybe we should use those instead? >> >> I don't understand your reluctance to parsing data, lots of ioctls do >> it. > > The reluctance comes from the parsing itself: you need to have input > validation, and it's hard to get right. The less we have, the easier it > gets. > >> And this data can only be loaded by root. What I like about having >> these properties in the config file is that the binding becomes a >> fallback binding that can actually be made to work without changing the >> Device Tree. >> >> For arguments sake let's say tiny/st7735r.c was not built and we had >> this node: >> >> display@0{ >> compatible = "jianda,jd-t18003-t01", "sitronix,st7735r", >> "panel-mipi-dbi-spi"; >> }; >> >> It will still be possible to use this display without changing the >> Device Tree. Just add a firmware/config file. >> >> Having the properties in DT it would have to look like this for the >> fallback to work: >> >> display@0{ >> compatible = "jianda,jd-t18003-t01", "sitronix,st7735r", >> "panel-mipi-dbi-spi"; >> panel-timing = { >> hactive = <128>; >> vactive = <128>; >> }; >> width-mm = <25>; >> height-mm = <26>; >> x-offset = <2>; >> y-offset = <3>; >> }; >> >> Is this important, I'm not sure. What do you think? > > Parts of it is ergonomics I guess. We're used to having all those > properties either in the DT or the driver, but here we introduce a new > way that isn't done anywhere else. > > And I don't see any real downside to putting it in the DT? It's going to > be in an overlay, under the user's control anyway, right? > Ok, I'll spin a new version using DT properties. Noralf.
Hi Noralf, > > > > Parts of it is ergonomics I guess. We're used to having all those > > properties either in the DT or the driver, but here we introduce a new > > way that isn't done anywhere else. > > > > And I don't see any real downside to putting it in the DT? It's going to > > be in an overlay, under the user's control anyway, right? > > > > Ok, I'll spin a new version using DT properties. I like this better than anything else as we then have everything in a single place when we add a new panel and more. I just recall some resistance to add such HW specific setup - but the usecase here is kinda special. Looks forward to see the updated patch! Sam
Hi Sam, On Wed, Feb 02, 2022 at 06:14:16PM +0100, Sam Ravnborg wrote: > Hi Noralf, > > > > > > > Parts of it is ergonomics I guess. We're used to having all those > > > properties either in the DT or the driver, but here we introduce a new > > > way that isn't done anywhere else. > > > > > > And I don't see any real downside to putting it in the DT? It's going to > > > be in an overlay, under the user's control anyway, right? > > > > > > > Ok, I'll spin a new version using DT properties. > > I like this better than anything else as we then have everything in > a single place when we add a new panel and more. > I just recall some resistance to add such HW specific setup - but the > usecase here is kinda special. The main issue was to put the initialisation sequence in the device tree. We solved that with by using a firmware instead. Given that the timings, size and so on are already used by multiple, widely used, panels, it should work just fine Maxime
diff --git a/MAINTAINERS b/MAINTAINERS index d03ad8da1f36..8baa98723bdc 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -6047,6 +6047,14 @@ T: git git://anongit.freedesktop.org/drm/drm-misc F: Documentation/devicetree/bindings/display/multi-inno,mi0283qt.txt F: drivers/gpu/drm/tiny/mi0283qt.c +DRM DRIVER FOR MIPI DBI compatible panels +M: Noralf Trønnes <noralf@tronnes.org> +S: Maintained +W: https://github.com/notro/panel-mipi-dbi/wiki +T: git git://anongit.freedesktop.org/drm/drm-misc +F: Documentation/devicetree/bindings/display/panel/panel-mipi-dbi-spi.yaml +F: drivers/gpu/drm/panel/panel-mipi-dbi.c + DRM DRIVER FOR MSM ADRENO GPU M: Rob Clark <robdclark@gmail.com> M: Sean Paul <sean@poorly.run> diff --git a/drivers/gpu/drm/panel/Kconfig b/drivers/gpu/drm/panel/Kconfig index 434c2861bb40..1851cda5f877 100644 --- a/drivers/gpu/drm/panel/Kconfig +++ b/drivers/gpu/drm/panel/Kconfig @@ -274,6 +274,17 @@ config DRM_PANEL_LG_LG4573 Say Y here if you want to enable support for LG4573 RGB panel. To compile this driver as a module, choose M here. +config DRM_PANEL_MIPI_DBI + tristate "MIPI DBI compatible panel" + depends on SPI + depends on BACKLIGHT_CLASS_DEVICE + depends on DRM_KMS_HELPER + select DRM_KMS_CMA_HELPER + select DRM_MIPI_DBI + help + Say Y here if you want to enable support for MIPI DBI compatible panels. + To compile this driver as a module, choose M here. + config DRM_PANEL_NEC_NL8048HL11 tristate "NEC NL8048HL11 RGB panel" depends on GPIOLIB && OF && SPI diff --git a/drivers/gpu/drm/panel/Makefile b/drivers/gpu/drm/panel/Makefile index d99fbbce49d1..a90c30459964 100644 --- a/drivers/gpu/drm/panel/Makefile +++ b/drivers/gpu/drm/panel/Makefile @@ -25,6 +25,7 @@ obj-$(CONFIG_DRM_PANEL_LEADTEK_LTK050H3146W) += panel-leadtek-ltk050h3146w.o obj-$(CONFIG_DRM_PANEL_LEADTEK_LTK500HD1829) += panel-leadtek-ltk500hd1829.o obj-$(CONFIG_DRM_PANEL_LG_LB035Q02) += panel-lg-lb035q02.o obj-$(CONFIG_DRM_PANEL_LG_LG4573) += panel-lg-lg4573.o +obj-$(CONFIG_DRM_PANEL_MIPI_DBI) += panel-mipi-dbi.o obj-$(CONFIG_DRM_PANEL_NEC_NL8048HL11) += panel-nec-nl8048hl11.o obj-$(CONFIG_DRM_PANEL_NOVATEK_NT35510) += panel-novatek-nt35510.o obj-$(CONFIG_DRM_PANEL_NOVATEK_NT35950) += panel-novatek-nt35950.o diff --git a/drivers/gpu/drm/panel/panel-mipi-dbi.c b/drivers/gpu/drm/panel/panel-mipi-dbi.c new file mode 100644 index 000000000000..6e3dc2de21d2 --- /dev/null +++ b/drivers/gpu/drm/panel/panel-mipi-dbi.c @@ -0,0 +1,394 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * DRM driver for MIPI DBI compatible display panels + * + * Copyright 2022 Noralf Trønnes + */ + +#include <linux/backlight.h> +#include <linux/delay.h> +#include <linux/firmware.h> +#include <linux/gpio/consumer.h> +#include <linux/module.h> +#include <linux/property.h> +#include <linux/regulator/consumer.h> +#include <linux/spi/spi.h> + +#include <drm/drm_atomic_helper.h> +#include <drm/drm_drv.h> +#include <drm/drm_fb_helper.h> +#include <drm/drm_gem_atomic_helper.h> +#include <drm/drm_gem_cma_helper.h> +#include <drm/drm_managed.h> +#include <drm/drm_mipi_dbi.h> +#include <drm/drm_modeset_helper.h> +#include <video/mipi_display.h> + +static const u8 panel_mipi_dbi_magic[15] = { 'M', 'I', 'P', 'I', ' ', 'D', 'B', 'I', + 0, 0, 0, 0, 0, 0, 0 }; + +/* + * The display panel configuration is stored in a firmware file. The Device Tree 'compatible' + * property value with a '.bin' suffix is passed to request_firmware() to fetch this file. + */ +struct panel_mipi_dbi_config { + /* Magic string: panel_mipi_dbi_magic */ + u8 magic[15]; + + /* Config file format version */ + u8 file_format_version; + + /* Width in pixels */ + __be16 width; + /* Height in pixels */ + __be16 height; + + /* Width in millimeters (optional) */ + __be16 width_mm; + /* Height in millimeters (optional) */ + __be16 height_mm; + + /* X-axis panel offset */ + __be16 x_offset; + /* Y-axis panel offset */ + __be16 y_offset; + + /* 4 pad bytes, must be zero */ + u8 pad[4]; + + /* + * Optional MIPI commands to execute when the display pipeline is enabled. + * This can be used to configure the display controller. + * + * The commands are stored in a byte array with the format: + * command, num_parameters, [ parameter, ...], command, ... + * + * Some commands require a pause before the next command can be received. + * Inserting a delay in the command sequence is done by using the NOP command with one + * parameter: delay in miliseconds (the No Operation command is part of the MIPI Display + * Command Set where it has no parameters). + * + * Example: + * command 0x11 + * sleep 120ms + * command 0xb1 parameters 0x01, 0x2c, 0x2d + * command 0x29 + * + * Byte sequence: + * 0x11 0x00 + * 0x00 0x01 0x78 + * 0xb1 0x03 0x01 0x2c 0x2d + * 0x29 0x00 + */ + u8 commands[]; +}; + +struct panel_mipi_dbi_commands { + const u8 *buf; + size_t len; +}; + +static void panel_mipi_dbi_enable(struct drm_simple_display_pipe *pipe, + struct drm_crtc_state *crtc_state, + struct drm_plane_state *plane_state) +{ + struct mipi_dbi_dev *dbidev = drm_to_mipi_dbi_dev(pipe->crtc.dev); + struct panel_mipi_dbi_commands *commands = dbidev->driver_private; + struct mipi_dbi *dbi = &dbidev->dbi; + unsigned int i = 0; + int ret, idx; + + if (!drm_dev_enter(pipe->crtc.dev, &idx)) + return; + + drm_dbg(pipe->crtc.dev, "\n"); + + ret = mipi_dbi_poweron_conditional_reset(dbidev); + if (ret < 0) + goto out_exit; + if (ret == 1) + goto out_enable; + + if (!commands) + goto out_enable; + + while (i < commands->len) { + u8 command = commands->buf[i++]; + u8 num_parameters = commands->buf[i++]; + const u8 *parameters = &commands->buf[i]; + + if (command == 0x00 && num_parameters == 1) + msleep(parameters[0]); + else if (num_parameters) + mipi_dbi_command_stackbuf(dbi, command, parameters, num_parameters); + else + mipi_dbi_command(dbi, command); + + i += num_parameters; + } + +out_enable: + mipi_dbi_enable_flush(dbidev, crtc_state, plane_state); +out_exit: + drm_dev_exit(idx); +} + +static const struct drm_simple_display_pipe_funcs panel_mipi_dbi_pipe_funcs = { + .enable = panel_mipi_dbi_enable, + .disable = mipi_dbi_pipe_disable, + .update = mipi_dbi_pipe_update, +}; + +DEFINE_DRM_GEM_CMA_FOPS(panel_mipi_dbi_fops); + +static const struct drm_driver panel_mipi_dbi_driver = { + .driver_features = DRIVER_GEM | DRIVER_MODESET | DRIVER_ATOMIC, + .fops = &panel_mipi_dbi_fops, + DRM_GEM_CMA_DRIVER_OPS_VMAP, + .debugfs_init = mipi_dbi_debugfs_init, + .name = "panel-mipi-dbi", + .desc = "MIPI DBI compatible display panel", + .date = "20220103", + .major = 1, + .minor = 0, +}; + +static int panel_mipi_dbi_parse_config(struct mipi_dbi_dev *dbidev, + struct drm_display_mode *mode, + const struct firmware *fw) +{ + const struct panel_mipi_dbi_config *config = (struct panel_mipi_dbi_config *)fw->data; + unsigned int width, height, x_offset, y_offset; + struct panel_mipi_dbi_commands *commands; + struct drm_device *drm = &dbidev->drm; + struct device *dev = dbidev->drm.dev; + size_t size = fw->size, commands_len; + unsigned int i = 0; + + if (size < sizeof(*config)) { + dev_err(dev, "config: file size=%zu is too small\n", size); + return -EINVAL; + } + + if (memcmp(config->magic, panel_mipi_dbi_magic, sizeof(config->magic))) { + dev_err(dev, "config: Bad magic: %15ph\n", config->magic); + return -EINVAL; + } + + if (config->file_format_version != 1) { + dev_err(dev, "config: version=%u is not supported\n", config->file_format_version); + return -EINVAL; + } + + width = be16_to_cpu(config->width); + height = be16_to_cpu(config->height); + x_offset = be16_to_cpu(config->x_offset); + y_offset = be16_to_cpu(config->y_offset); + + drm_dbg(drm, "size=%zu version=%u\n", size, config->file_format_version); + drm_dbg(drm, "width=%u height=%u\n", width, height); + drm_dbg(drm, "x_offset=%u y_offset=%u\n", x_offset, y_offset); + + if (width && height) { + struct drm_display_mode simple_mode = { + DRM_SIMPLE_MODE(width, height, be16_to_cpu(config->width_mm), + be16_to_cpu(config->height_mm)) + }; + + *mode = simple_mode; + } else { + dev_err(dev, "config: width or height can't be zero\n"); + return -EINVAL; + } + + dbidev->left_offset = x_offset; + dbidev->top_offset = y_offset; + + commands_len = size - sizeof(*config); + if (!commands_len) + return 0; + + while ((i + 1) < commands_len) { + u8 command = config->commands[i++]; + u8 num_parameters = config->commands[i++]; + const u8 *parameters = &config->commands[i]; + + i += num_parameters; + if (i > commands_len) { + dev_err(dev, "config: command=0x%02x num_parameters=%u overflows\n", + command, num_parameters); + return -EINVAL; + } + + if (command == 0x00 && num_parameters == 1) + drm_dbg(drm, "sleep %ums\n", parameters[0]); + else + drm_dbg(drm, "command %02x %*ph\n", command, num_parameters, parameters); + } + + if (i != commands_len) { + dev_err(dev, "config: malformed command array\n"); + return -EINVAL; + } + + commands = devm_kzalloc(dev, sizeof(*commands), GFP_KERNEL); + if (!commands) + return -ENOMEM; + + commands->len = commands_len; + commands->buf = devm_kmemdup(dev, config->commands, commands->len, GFP_KERNEL); + if (!commands->buf) + return -ENOMEM; + + dbidev->driver_private = commands; + + return 0; +} + +static int panel_mipi_dbi_spi_probe(struct spi_device *spi) +{ + struct device *dev = &spi->dev; + struct drm_display_mode mode; + struct mipi_dbi_dev *dbidev; + const struct firmware *fw; + const char *compatible; + struct drm_device *drm; + struct property *prop; + bool fw_found = false; + struct mipi_dbi *dbi; + struct gpio_desc *dc; + char fw_name[40]; + int ret; + + dbidev = devm_drm_dev_alloc(dev, &panel_mipi_dbi_driver, struct mipi_dbi_dev, drm); + if (IS_ERR(dbidev)) + return PTR_ERR(dbidev); + + dbi = &dbidev->dbi; + drm = &dbidev->drm; + + of_property_for_each_string(dev->of_node, "compatible", prop, compatible) { + snprintf(fw_name, sizeof(fw_name), "%s.bin", compatible); + + ret = firmware_request_nowarn(&fw, fw_name, dev); + if (ret) { + drm_dbg(drm, "No config file found for compatible: '%s' (error=%d)\n", + compatible, ret); + continue; + } + + ret = panel_mipi_dbi_parse_config(dbidev, &mode, fw); + release_firmware(fw); + if (ret) + return ret; + + fw_found = true; + break; + } + + if (!fw_found) { + dev_err(dev, "No config file found\n"); + return -ENOENT; + } + + dbidev->regulator = devm_regulator_get(dev, "power"); + if (IS_ERR(dbidev->regulator)) + return dev_err_probe(dev, PTR_ERR(dbidev->regulator), + "Failed to get regulator 'power'\n"); + + dbi->reset = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_HIGH); + if (IS_ERR(dbi->reset)) + return dev_err_probe(dev, PTR_ERR(dbi->reset), "Failed to get GPIO 'reset'\n"); + + dc = devm_gpiod_get_optional(dev, "dc", GPIOD_OUT_LOW); + if (IS_ERR(dc)) + return dev_err_probe(dev, PTR_ERR(dc), "Failed to get GPIO 'dc'\n"); + + dbidev->backlight = devm_of_find_backlight(dev); + if (IS_ERR(dbidev->backlight)) + return dev_err_probe(dev, PTR_ERR(dbidev->backlight), "Failed to get backlight\n"); + + ret = mipi_dbi_spi_init(spi, dbi, dc); + if (ret) + return ret; + + if (device_property_present(dev, "write-only")) + dbi->read_commands = NULL; + + ret = mipi_dbi_dev_init(dbidev, &panel_mipi_dbi_pipe_funcs, &mode, 0); + if (ret) + return ret; + + drm_mode_config_reset(drm); + + ret = drm_dev_register(drm, 0); + if (ret) + return ret; + + spi_set_drvdata(spi, drm); + + drm_fbdev_generic_setup(drm, 0); + + return 0; +} + +static int panel_mipi_dbi_spi_remove(struct spi_device *spi) +{ + struct drm_device *drm = spi_get_drvdata(spi); + + drm_dev_unplug(drm); + drm_atomic_helper_shutdown(drm); + + return 0; +} + +static void panel_mipi_dbi_spi_shutdown(struct spi_device *spi) +{ + drm_atomic_helper_shutdown(spi_get_drvdata(spi)); +} + +static int __maybe_unused panel_mipi_dbi_pm_suspend(struct device *dev) +{ + return drm_mode_config_helper_suspend(dev_get_drvdata(dev)); +} + +static int __maybe_unused panel_mipi_dbi_pm_resume(struct device *dev) +{ + drm_mode_config_helper_resume(dev_get_drvdata(dev)); + + return 0; +} + +static const struct dev_pm_ops panel_mipi_dbi_pm_ops = { + SET_SYSTEM_SLEEP_PM_OPS(panel_mipi_dbi_pm_suspend, panel_mipi_dbi_pm_resume) +}; + +static const struct of_device_id panel_mipi_dbi_spi_of_match[] = { + { .compatible = "panel-mipi-dbi-spi" }, + {}, +}; +MODULE_DEVICE_TABLE(of, panel_mipi_dbi_spi_of_match); + +static const struct spi_device_id panel_mipi_dbi_spi_id[] = { + { "panel-mipi-dbi-spi", 0 }, + { }, +}; +MODULE_DEVICE_TABLE(spi, panel_mipi_dbi_spi_id); + +static struct spi_driver panel_mipi_dbi_spi_driver = { + .driver = { + .name = "panel-mipi-dbi-spi", + .owner = THIS_MODULE, + .of_match_table = panel_mipi_dbi_spi_of_match, + .pm = &panel_mipi_dbi_pm_ops, + }, + .id_table = panel_mipi_dbi_spi_id, + .probe = panel_mipi_dbi_spi_probe, + .remove = panel_mipi_dbi_spi_remove, + .shutdown = panel_mipi_dbi_spi_shutdown, +}; +module_spi_driver(panel_mipi_dbi_spi_driver); + +MODULE_DESCRIPTION("MIPI DBI compatible display panel driver"); +MODULE_AUTHOR("Noralf Trønnes"); +MODULE_LICENSE("GPL");
Add a driver that will work with most MIPI DBI compatible SPI panels. This avoids adding a driver for every new MIPI DBI compatible controller that is to be used by Linux. The 'compatible' Device Tree property with a '.bin' suffix will be used to load a firmware file that contains the controller configuration. Example (driver will load sainsmart18.bin): display@0 { compatible = "sainsmart18", "panel-mipi-dbi-spi"; reg = <0>; reset-gpios = <&gpio 25 0>; dc-gpios = <&gpio 24 0>; }; v2: - Drop model property and use compatible instead (Rob) - Add wiki entry in MAINTAINERS Signed-off-by: Noralf Trønnes <noralf@tronnes.org> --- MAINTAINERS | 8 + drivers/gpu/drm/panel/Kconfig | 11 + drivers/gpu/drm/panel/Makefile | 1 + drivers/gpu/drm/panel/panel-mipi-dbi.c | 394 +++++++++++++++++++++++++ 4 files changed, 414 insertions(+) create mode 100644 drivers/gpu/drm/panel/panel-mipi-dbi.c