Commit b09f6ca9 authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge tag 'acpi-6.11-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm 

Pull ACPI fix from Rafael Wysocki:
 "Fix backlight control on a Dell All In One system where a backlight
  controller board is attached to a UART port and the dell-uart
  backlight driver binds to it, but the backlight is actually controlled
  by other means (Hans de Goede)"

* tag 'acpi-6.11-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  ACPI: video: Add backlight=native quirk for Dell OptiPlex 7760 AIO
  platform/x86: dell-uart-backlight: Use acpi_video_get_backlight_type()
  ACPI: video: Add Dell UART backlight controller detection
parents 6ae4e48b 5c7bb62c

drivers/acpi/video_detect.c

+22 −0
Original line number Diff line number Diff line
@@ -54,6 +54,8 @@ static void acpi_video_parse_cmdline(void) 
		acpi_backlight_cmdline = acpi_backlight_nvidia_wmi_ec;

	if (!strcmp("apple_gmux", acpi_video_backlight_string))

		acpi_backlight_cmdline = acpi_backlight_apple_gmux;

	if (!strcmp("dell_uart", acpi_video_backlight_string))

		acpi_backlight_cmdline = acpi_backlight_dell_uart;

	if (!strcmp("none", acpi_video_backlight_string))

		acpi_backlight_cmdline = acpi_backlight_none;

}
@@ -821,6 +823,21 @@ static const struct dmi_system_id video_detect_dmi_table[] = { 
		},

	},



	/*

	 * Dell AIO (All in Ones) which advertise an UART attached backlight

	 * controller board in their ACPI tables (and may even have one), but

	 * which need native backlight control nevertheless.

	 */

	{

	 /* https://bugzilla.redhat.com/show_bug.cgi?id=2303936 */

	 .callback = video_detect_force_native,

	 /* Dell OptiPlex 7760 AIO */

	 .matches = {

		DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),

		DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 7760 AIO"),

		},

	},



	/*

	 * Models which have nvidia-ec-wmi support, but should not use it.

	 * Note this indicates a likely firmware bug on these models and should
@@ -918,6 +935,7 @@ enum acpi_backlight_type __acpi_video_get_backlight_type(bool native, bool *auto 
	static DEFINE_MUTEX(init_mutex);

	static bool nvidia_wmi_ec_present;

	static bool apple_gmux_present;

	static bool dell_uart_present;

	static bool native_available;

	static bool init_done;

	static long video_caps;
@@ -932,6 +950,7 @@ enum acpi_backlight_type __acpi_video_get_backlight_type(bool native, bool *auto 
				    &video_caps, NULL);

		nvidia_wmi_ec_present = nvidia_wmi_ec_supported();

		apple_gmux_present = apple_gmux_detect(NULL, NULL);

		dell_uart_present = acpi_dev_present("DELL0501", NULL, -1);

		init_done = true;

	}

	if (native)
@@ -962,6 +981,9 @@ enum acpi_backlight_type __acpi_video_get_backlight_type(bool native, bool *auto 
	if (apple_gmux_present)

		return acpi_backlight_apple_gmux;



	if (dell_uart_present)

		return acpi_backlight_dell_uart;



	/* Use ACPI video if available, except when native should be preferred. */

	if ((video_caps & ACPI_VIDEO_BACKLIGHT) &&

	     !(native_available && prefer_native_over_acpi_video()))

drivers/platform/x86/dell/Kconfig

+1 −0
Original line number Diff line number Diff line
@@ -161,6 +161,7 @@ config DELL_SMO8800 
config DELL_UART_BACKLIGHT

	tristate "Dell AIO UART Backlight driver"

	depends on ACPI

	depends on ACPI_VIDEO

	depends on BACKLIGHT_CLASS_DEVICE

	depends on SERIAL_DEV_BUS

	help

drivers/platform/x86/dell/dell-uart-backlight.c

+8 −0
Original line number Diff line number Diff line
@@ -20,6 +20,7 @@ 
#include <linux/string.h>

#include <linux/types.h>

#include <linux/wait.h>

#include <acpi/video.h>

#include "../serdev_helpers.h"



/* The backlight controller must respond within 1 second */
@@ -332,10 +333,17 @@ struct serdev_device_driver dell_uart_bl_serdev_driver = { 


static int dell_uart_bl_pdev_probe(struct platform_device *pdev)

{

	enum acpi_backlight_type bl_type;

	struct serdev_device *serdev;

	struct device *ctrl_dev;

	int ret;



	bl_type = acpi_video_get_backlight_type();

	if (bl_type != acpi_backlight_dell_uart) {

		dev_dbg(&pdev->dev, "Not loading (ACPI backlight type = %d)\n", bl_type);

		return -ENODEV;

	}



	ctrl_dev = get_serdev_controller("DELL0501", NULL, 0, "serial0");

	if (IS_ERR(ctrl_dev))

		return PTR_ERR(ctrl_dev);

include/acpi/video.h

+1 −0
Original line number Diff line number Diff line
@@ -50,6 +50,7 @@ enum acpi_backlight_type { 
	acpi_backlight_native,

	acpi_backlight_nvidia_wmi_ec,

	acpi_backlight_apple_gmux,

	acpi_backlight_dell_uart,

};



#if IS_ENABLED(CONFIG_ACPI_VIDEO)