Add binding for MIPI DBI compatible SPI panels.

v6: - Fix indentation (Rob)

v5: - Add sainsmart18 to compatible items (Rob) - Expand write-only description (Sam)

v4: - There should only be two compatible (Maxime) - s/panel-dbi-spi/panel-mipi-dbi-spi/in compatible

v3: - Move properties to Device Tree (Maxime) - Use contains for compatible (Maxime) - Add backlight property to example - Flesh out description

v2: - Fix path for panel-common.yaml - Use unevaluatedProperties - Drop properties which are in the allOf section - Drop model property (Rob)

Acked-by: Maxime Ripard maxime@cerno.tech Acked-by: Sam Ravnborg sam@ravnborg.org Reviewed-by: Rob Herring robh@kernel.org Signed-off-by: Noralf Trønnes noralf@tronnes.org --- .../display/panel/panel-mipi-dbi-spi.yaml | 126 ++++++++++++++++++ 1 file changed, 126 insertions(+) create mode 100644 Documentation/devicetree/bindings/display/panel/panel-mipi-dbi-spi.yaml

diff --git a/Documentation/devicetree/bindings/display/panel/panel-mipi-dbi-spi.yaml b/Documentation/devicetree/bindings/display/panel/panel-mipi-dbi-spi.yaml new file mode 100644 index 000000000000..f29789994b18 --- /dev/null +++ b/Documentation/devicetree/bindings/display/panel/panel-mipi-dbi-spi.yaml @@ -0,0 +1,126 @@ +# SPDX-License-Identifier: (GPL-2.0-only or BSD-2-Clause) +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/display/panel/panel-mipi-dbi-spi.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: MIPI DBI SPI Panel + +maintainers: + - Noralf Trønnes noralf@tronnes.org + +description: | + This binding is for display panels using a MIPI DBI compatible controller + in SPI mode. + + The MIPI Alliance Standard for Display Bus Interface defines the electrical + and logical interfaces for display controllers historically used in mobile + phones. The standard defines 4 display architecture types and this binding is + for type 1 which has full frame memory. There are 3 interface types in the + standard and type C is the serial interface. + + The standard defines the following interface signals for type C: + - Power: + - Vdd: Power supply for display module + - Vddi: Logic level supply for interface signals + Combined into one in this binding called: power-supply + - Interface: + - CSx: Chip select + - SCL: Serial clock + - Dout: Serial out + - Din: Serial in + - SDA: Bidrectional in/out + - D/CX: Data/command selection, high=data, low=command + Called dc-gpios in this binding. + - RESX: Reset when low + Called reset-gpios in this binding. + + The type C interface has 3 options: + + - Option 1: 9-bit mode and D/CX as the 9th bit + | Command | the next command or following data | + |<0><D7><D6><D5><D4><D3><D2><D1><D0>|<D/CX><D7><D6><D5><D4><D3><D2><D1><D0>| + + - Option 2: 16-bit mode and D/CX as a 9th bit + | Command or data | + |<X><X><X><X><X><X><X><D/CX><D7><D6><D5><D4><D3><D2><D1><D0>| + + - Option 3: 8-bit mode and D/CX as a separate interface line + | Command or data | + |<D7><D6><D5><D4><D3><D2><D1><D0>| + + The panel resolution is specified using the panel-timing node properties + hactive (width) and vactive (height). The other mandatory panel-timing + properties should be set to zero except clock-frequency which can be + optionally set to inform about the actual pixel clock frequency. + + If the panel is wired to the controller at an offset specify this using + hback-porch (x-offset) and vback-porch (y-offset). + +allOf: + - $ref: panel-common.yaml# + - $ref: /schemas/spi/spi-peripheral-props.yaml# + +properties: + compatible: + items: + - enum: + - sainsmart18 + - const: panel-mipi-dbi-spi + + write-only: + type: boolean + description: + Controller is not readable (ie. Din (MISO on the SPI interface) is not + wired up). + + dc-gpios: + maxItems: 1 + description: | + Controller data/command selection (D/CX) in 4-line SPI mode. + If not set, the controller is in 3-line SPI mode. + +required: + - compatible + - reg + - panel-timing + +unevaluatedProperties: false + +examples: + - | + #include <dt-bindings/gpio/gpio.h> + + spi { + #address-cells = <1>; + #size-cells = <0>; + + display@0{ + compatible = "sainsmart18", "panel-mipi-dbi-spi"; + reg = <0>; + spi-max-frequency = <40000000>; + + dc-gpios = <&gpio 24 GPIO_ACTIVE_HIGH>; + reset-gpios = <&gpio 25 GPIO_ACTIVE_HIGH>; + write-only; + + backlight = <&backlight>; + + width-mm = <35>; + height-mm = <28>; + + panel-timing { + hactive = <160>; + vactive = <128>; + hback-porch = <0>; + vback-porch = <0>; + clock-frequency = <0>; + hfront-porch = <0>; + hsync-len = <0>; + vfront-porch = <0>; + vsync-len = <0>; + }; + }; + }; + +...

Remove trailing whitespace from a comment.

Acked-by: Sam Ravnborg sam@ravnborg.org Signed-off-by: Noralf Trønnes noralf@tronnes.org --- drivers/gpu/drm/drm_modes.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/drm_modes.c b/drivers/gpu/drm/drm_modes.c index 96b13e36293c..77a4c8dd0bb8 100644 --- a/drivers/gpu/drm/drm_modes.c +++ b/drivers/gpu/drm/drm_modes.c @@ -127,7 +127,7 @@ EXPORT_SYMBOL(drm_mode_probed_add); * according to the hdisplay, vdisplay, vrefresh. * It is based from the VESA(TM) Coordinated Video Timing Generator by * Graham Loveridge April 9, 2003 available at - * http://www.elo.utfsm.cl/~elo212/docs/CVTd6r1.xls + * http://www.elo.utfsm.cl/~elo212/docs/CVTd6r1.xls * * And it is copied from xf86CVTmode in xserver/hw/xfree86/modes/xf86cvt.c. * What I have done is to translate it by using integer calculation.

Add a function to get a drm_display_mode from a panel-timing device tree subnode.

Suggested-by: Sam Ravnborg sam@ravnborg.org Reviewed-by: Sam Ravnborg sam@ravnborg.org Signed-off-by: Noralf Trønnes noralf@tronnes.org --- drivers/gpu/drm/drm_modes.c | 49 +++++++++++++++++++++++++++++++++++++ include/drm/drm_modes.h | 8 ++++++ 2 files changed, 57 insertions(+)

diff --git a/drivers/gpu/drm/drm_modes.c b/drivers/gpu/drm/drm_modes.c index 77a4c8dd0bb8..3f819c7a021b 100644 --- a/drivers/gpu/drm/drm_modes.c +++ b/drivers/gpu/drm/drm_modes.c @@ -35,6 +35,7 @@ #include <linux/list_sort.h> #include <linux/export.h>

+#include <video/of_display_timing.h> #include <video/of_videomode.h> #include <video/videomode.h>

@@ -727,6 +728,54 @@ int of_get_drm_display_mode(struct device_node *np, return 0; } EXPORT_SYMBOL_GPL(of_get_drm_display_mode); + +/** + * of_get_drm_panel_display_mode - get a panel-timing drm_display_mode from devicetree + * @np: device_node with the panel-timing specification + * @dmode: will be set to the return value + * @bus_flags: information about pixelclk, sync and DE polarity + * + * The Device Tree properties width-mm and height-mm will be read and set on + * the display mode if they are present. + * + * Returns: + * Zero on success, negative error code on failure. + */ +int of_get_drm_panel_display_mode(struct device_node *np, + struct drm_display_mode *dmode, u32 *bus_flags) +{ + u32 width_mm = 0, height_mm = 0; + struct display_timing timing; + struct videomode vm; + int ret; + + ret = of_get_display_timing(np, "panel-timing", &timing); + if (ret) + return ret; + + videomode_from_timing(&timing, &vm); + + memset(dmode, 0, sizeof(*dmode)); + drm_display_mode_from_videomode(&vm, dmode); + if (bus_flags) + drm_bus_flags_from_videomode(&vm, bus_flags); + + ret = of_property_read_u32(np, "width-mm", &width_mm); + if (ret && ret != -EINVAL) + return ret; + + ret = of_property_read_u32(np, "height-mm", &height_mm); + if (ret && ret != -EINVAL) + return ret; + + dmode->width_mm = width_mm; + dmode->height_mm = height_mm; + + drm_mode_debug_printmodeline(dmode); + + return 0; +} +EXPORT_SYMBOL_GPL(of_get_drm_panel_display_mode); #endif /* CONFIG_OF */ #endif /* CONFIG_VIDEOMODE_HELPERS */

diff --git a/include/drm/drm_modes.h b/include/drm/drm_modes.h index 29ba4adf0c53..2fa6b2c33b3f 100644 --- a/include/drm/drm_modes.h +++ b/include/drm/drm_modes.h @@ -466,6 +466,8 @@ void drm_bus_flags_from_videomode(const struct videomode *vm, u32 *bus_flags); int of_get_drm_display_mode(struct device_node *np, struct drm_display_mode *dmode, u32 *bus_flags, int index); +int of_get_drm_panel_display_mode(struct device_node *np, + struct drm_display_mode *dmode, u32 *bus_flags); #else static inline int of_get_drm_display_mode(struct device_node *np, struct drm_display_mode *dmode, @@ -473,6 +475,12 @@ static inline int of_get_drm_display_mode(struct device_node *np, { return -EINVAL; } + +static inline int of_get_drm_panel_display_mode(struct device_node *np, + struct drm_display_mode *dmode, u32 *bus_flags) +{ + return -EINVAL; +} #endif

void drm_mode_set_name(struct drm_display_mode *mode);

devm_drm_dev_alloc() can't allocate structures that embed a structure which then again embeds drm_device. Workaround this by adding a driver_private pointer to struct mipi_dbi_dev which the driver can use for its additional state.

v3: - Add documentation

Acked-by: Maxime Ripard maxime@cerno.tech Acked-by: Sam Ravnborg sam@ravnborg.org Signed-off-by: Noralf Trønnes noralf@tronnes.org --- include/drm/drm_mipi_dbi.h | 8 ++++++++ 1 file changed, 8 insertions(+)

diff --git a/include/drm/drm_mipi_dbi.h b/include/drm/drm_mipi_dbi.h index 6fe13cce2670..dad2f187b64b 100644 --- a/include/drm/drm_mipi_dbi.h +++ b/include/drm/drm_mipi_dbi.h @@ -130,6 +130,14 @@ struct mipi_dbi_dev { * @dbi: MIPI DBI interface */ struct mipi_dbi dbi; + + /** + * @driver_private: Driver private data. + * Necessary for drivers with private data since devm_drm_dev_alloc() + * can't allocate structures that embed a structure which then again + * embeds drm_device. + */ + void *driver_private; };

static inline struct mipi_dbi_dev *drm_to_mipi_dbi_dev(struct drm_device *drm)

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"; ... };

v5: - kconfig: s/DRM_KMS_CMA_HELPER/DRM_GEM_CMA_HELPER/ (Sam) - kconfig: Add select VIDEOMODE_HELPERS (Sam) - kconfig: Add wiki url in the description (Sam) - Split out and use of_get_drm_panel_display_mode()(Sam) - Only use the first compatible to look for a firmware file since the binding mandates 2 compatibles. - Make having a firmware file mandatory so we can print an error message if it's missing to improve the user experience. It's very unlikely that a controller doesn't need to be initialized and if it doesn't, it's possible to have a firmware file containing only a DCS NOP.

v4: - Move driver to drm/tiny where the other drivers of its kind are located. The driver module will not be shared with a future DPI driver after all.

v3: - Move properties to DT (Maxime) - The MIPI DPI spec has optional support for DPI where the controller is configured over DBI. Rework the command functions so they can be moved to drm_mipi_dbi and shared with a future panel-mipi-dpi-spi driver

v2: - Drop model property and use compatible instead (Rob) - Add wiki entry in MAINTAINERS

Acked-by: Maxime Ripard maxime@cerno.tech Reviewed-by: Sam Ravnborg sam@ravnborg.org Signed-off-by: Noralf Trønnes noralf@tronnes.org --- MAINTAINERS | 8 + drivers/gpu/drm/tiny/Kconfig | 15 + drivers/gpu/drm/tiny/Makefile | 1 + drivers/gpu/drm/tiny/panel-mipi-dbi.c | 398 ++++++++++++++++++++++++++ 4 files changed, 422 insertions(+) create mode 100644 drivers/gpu/drm/tiny/panel-mipi-dbi.c

diff --git a/MAINTAINERS b/MAINTAINERS index 8e6e892f99f0..3a0e57f23ad0 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -6107,6 +6107,14 @@ 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/tiny/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/tiny/Kconfig b/drivers/gpu/drm/tiny/Kconfig index 712e0004e96e..627d637a1e7e 100644 --- a/drivers/gpu/drm/tiny/Kconfig +++ b/drivers/gpu/drm/tiny/Kconfig @@ -51,6 +51,21 @@ config DRM_GM12U320 This is a KMS driver for projectors which use the GM12U320 chipset for video transfer over USB2/3, such as the Acer C120 mini projector.

+config DRM_PANEL_MIPI_DBI + tristate "DRM support for MIPI DBI compatible panels" + depends on DRM && SPI + select DRM_KMS_HELPER + select DRM_GEM_CMA_HELPER + select DRM_MIPI_DBI + select BACKLIGHT_CLASS_DEVICE + select VIDEOMODE_HELPERS + help + Say Y here if you want to enable support for MIPI DBI compatible + panels. The controller command setup can be provided using a + firmware file. For more information see + https://github.com/notro/panel-mipi-dbi/wiki. + To compile this driver as a module, choose M here. + config DRM_SIMPLEDRM tristate "Simple framebuffer driver" depends on DRM && MMU diff --git a/drivers/gpu/drm/tiny/Makefile b/drivers/gpu/drm/tiny/Makefile index 5d5505d40e7b..1d9d6227e7ab 100644 --- a/drivers/gpu/drm/tiny/Makefile +++ b/drivers/gpu/drm/tiny/Makefile @@ -4,6 +4,7 @@ obj-$(CONFIG_DRM_ARCPGU) += arcpgu.o obj-$(CONFIG_DRM_BOCHS) += bochs.o obj-$(CONFIG_DRM_CIRRUS_QEMU) += cirrus.o obj-$(CONFIG_DRM_GM12U320) += gm12u320.o +obj-$(CONFIG_DRM_PANEL_MIPI_DBI) += panel-mipi-dbi.o obj-$(CONFIG_DRM_SIMPLEDRM) += simpledrm.o obj-$(CONFIG_TINYDRM_HX8357D) += hx8357d.o obj-$(CONFIG_TINYDRM_ILI9163) += ili9163.o diff --git a/drivers/gpu/drm/tiny/panel-mipi-dbi.c b/drivers/gpu/drm/tiny/panel-mipi-dbi.c new file mode 100644 index 000000000000..7f8c6c51387f --- /dev/null +++ b/drivers/gpu/drm/tiny/panel-mipi-dbi.c @@ -0,0 +1,398 @@ +// 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_modes.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 controller 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; + + /* + * MIPI commands to execute when the display pipeline is enabled. + * This is 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 struct panel_mipi_dbi_commands * +panel_mipi_dbi_check_commands(struct device *dev, const struct firmware *fw) +{ + const struct panel_mipi_dbi_config *config = (struct panel_mipi_dbi_config *)fw->data; + struct panel_mipi_dbi_commands *commands; + size_t size = fw->size, commands_len; + unsigned int i = 0; + + if (size < sizeof(*config) + 2) { /* At least 1 command */ + dev_err(dev, "config: file size=%zu is too small\n", size); + return ERR_PTR(-EINVAL); + } + + if (memcmp(config->magic, panel_mipi_dbi_magic, sizeof(config->magic))) { + dev_err(dev, "config: Bad magic: %15ph\n", config->magic); + return ERR_PTR(-EINVAL); + } + + if (config->file_format_version != 1) { + dev_err(dev, "config: version=%u is not supported\n", config->file_format_version); + return ERR_PTR(-EINVAL); + } + + drm_dev_dbg(dev, DRM_UT_DRIVER, "size=%zu version=%u\n", size, config->file_format_version); + + commands_len = size - sizeof(*config); + + 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 ERR_PTR(-EINVAL); + } + + if (command == 0x00 && num_parameters == 1) + drm_dev_dbg(dev, DRM_UT_DRIVER, "sleep %ums\n", parameters[0]); + else + drm_dev_dbg(dev, DRM_UT_DRIVER, "command %02x %*ph\n", + command, num_parameters, parameters); + } + + if (i != commands_len) { + dev_err(dev, "config: malformed command array\n"); + return ERR_PTR(-EINVAL); + } + + commands = devm_kzalloc(dev, sizeof(*commands), GFP_KERNEL); + if (!commands) + return ERR_PTR(-ENOMEM); + + commands->len = commands_len; + commands->buf = devm_kmemdup(dev, config->commands, commands->len, GFP_KERNEL); + if (!commands->buf) + return ERR_PTR(-ENOMEM); + + return commands; +} + +static struct panel_mipi_dbi_commands *panel_mipi_dbi_commands_from_fw(struct device *dev) +{ + struct panel_mipi_dbi_commands *commands; + const struct firmware *fw; + const char *compatible; + char fw_name[40]; + int ret; + + ret = of_property_read_string_index(dev->of_node, "compatible", 0, &compatible); + if (ret) + return ERR_PTR(ret); + + snprintf(fw_name, sizeof(fw_name), "%s.bin", compatible); + ret = request_firmware(&fw, fw_name, dev); + if (ret) { + dev_err(dev, "No config file found for compatible '%s' (error=%d)\n", + compatible, ret); + + return ERR_PTR(ret); + } + + commands = panel_mipi_dbi_check_commands(dev, fw); + release_firmware(fw); + + return commands; +} + +static void panel_mipi_dbi_commands_execute(struct mipi_dbi *dbi, + struct panel_mipi_dbi_commands *commands) +{ + unsigned int i = 0; + + if (!commands) + return; + + 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; + } +} + +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 mipi_dbi *dbi = &dbidev->dbi; + 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) + panel_mipi_dbi_commands_execute(dbi, dbidev->driver_private); + + 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_get_mode(struct mipi_dbi_dev *dbidev, struct drm_display_mode *mode) +{ + struct device *dev = dbidev->drm.dev; + u16 hback_porch, vback_porch; + int ret; + + ret = of_get_drm_panel_display_mode(dev->of_node, mode, NULL); + if (ret) { + dev_err(dev, "%pOF: failed to get panel-timing (error=%d)\n", dev->of_node, ret); + return ret; + } + + mode->type = DRM_MODE_TYPE_DRIVER | DRM_MODE_TYPE_PREFERRED; + + hback_porch = mode->htotal - mode->hsync_end; + vback_porch = mode->vtotal - mode->vsync_end; + + /* + * Make sure width and height are set and that only back porch and + * pixelclock are set in the other timing values. Also check that + * width and height don't exceed the 16-bit value specified by MIPI DCS. + */ + if (!mode->hdisplay || !mode->vdisplay || mode->flags || + mode->hsync_end > mode->hdisplay || (hback_porch + mode->hdisplay) > 0xffff || + mode->vsync_end > mode->vdisplay || (vback_porch + mode->vdisplay) > 0xffff) { + dev_err(dev, "%pOF: panel-timing out of bounds\n", dev->of_node); + return -EINVAL; + } + + /* The driver doesn't use the pixel clock but it is mandatory so fake one if not set */ + if (!mode->clock) + mode->clock = mode->htotal * mode->vtotal * 60 / 1000; + + dbidev->top_offset = vback_porch; + dbidev->left_offset = hback_porch; + + 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; + struct drm_device *drm; + struct mipi_dbi *dbi; + struct gpio_desc *dc; + 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; + + ret = panel_mipi_dbi_get_mode(dbidev, &mode); + if (ret) + return ret; + + 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"); + + 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"); + + 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"); + + ret = mipi_dbi_spi_init(spi, dbi, dc); + if (ret) + return ret; + + if (device_property_present(dev, "write-only")) + dbi->read_commands = NULL; + + dbidev->driver_private = panel_mipi_dbi_commands_from_fw(dev); + if (IS_ERR(dbidev->driver_private)) + return PTR_ERR(dbidev->driver_private); + + 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");