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authorLinus Torvalds <torvalds@linux-foundation.org>2019-05-07 18:02:51 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2019-05-07 18:02:51 -0700
commit8b35ad6232c462b02e397e87ce702bcddd4ba543 (patch)
tree921cd619336b1ff7f0dde7bdbf9f898ffe4cedae /Documentation
parentf678d6da749983791850876e3421e7c48a0a7127 (diff)
parent0db37915d912e8dc6588f25da76d3ed36718d92f (diff)
downloadlinux-8b35ad6232c462b02e397e87ce702bcddd4ba543.tar.bz2
Merge tag 'leds-for-5.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/j.anaszewski/linux-leds
Pull LED updates from Jacek Anaszewski: "LED core fixes and improvements: - avoid races with workqueue - Kconfig: pedantic cleanup - small fixes for Flash class description leds-lt3593: - remove unneeded assignment in lt3593_led_probe - drop pdata handling code leds-blinkm: - clean up double assignment to data->i2c_addr leds-pca955x, leds-pca963x: - revert ACPI support, as it turned out that there is no evidence of officially registered ACPI IDs for these devices. - make use of device property API leds-as3645a: - switch to fwnode property API LED related addition to ACPI documentation: - document how to refer to LEDs from remote nodes LED related fix to ALSA line6/toneport driver: - avoid polluting led_* namespace And lm3532 driver relocation from MFD to LED subsystem, accompanied by various improvements and optimizations; it entails also a change in omap4-droid4-xt894.dts: - leds: lm3532: Introduce the lm3532 LED driver - mfd: ti-lmu: Remove LM3532 backlight driver references - ARM: dts: omap4-droid4: Update backlight dt properties - dt: lm3532: Add lm3532 dt doc and update ti_lmu doc" * tag 'leds-for-5.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/j.anaszewski/linux-leds: leds: avoid races with workqueue ALSA: line6: Avoid polluting led_* namespace leds: lm3532: Introduce the lm3532 LED driver mfd: ti-lmu: Remove LM3532 backlight driver references ARM: dts: omap4-droid4: Update backlight dt properties dt: lm3532: Add lm3532 dt doc and update ti_lmu doc leds: Small fixes for Flash class description leds: blinkm: clean up double assignment to data->i2c_addr leds: pca963x: Make use of device property API leds: pca955x: Make use of device property API leds: lt3593: Remove unneeded assignment in lt3593_led_probe leds: lt3593: drop pdata handling code leds: pca955x: Revert "Add ACPI support" leds: pca963x: Revert "Add ACPI support" drivers: leds: Kconfig: pedantic cleanups ACPI: Document how to refer to LEDs from remote nodes leds: as3645a: Switch to fwnode property API
Diffstat (limited to 'Documentation')
-rw-r--r--Documentation/acpi/dsd/leds.txt99
-rw-r--r--Documentation/devicetree/bindings/leds/leds-lm3532.txt101
-rw-r--r--Documentation/devicetree/bindings/mfd/ti-lmu.txt20
3 files changed, 200 insertions, 20 deletions
diff --git a/Documentation/acpi/dsd/leds.txt b/Documentation/acpi/dsd/leds.txt
new file mode 100644
index 000000000000..81a63af42ed2
--- /dev/null
+++ b/Documentation/acpi/dsd/leds.txt
@@ -0,0 +1,99 @@
+Describing and referring to LEDs in ACPI
+
+Individual LEDs are described by hierarchical data extension [6] nodes under the
+device node, the LED driver chip. The "reg" property in the LED specific nodes
+tells the numerical ID of each individual LED output to which the LEDs are
+connected. [3] The hierarchical data nodes are named "led@X", where X is the
+number of the LED output.
+
+Referring to LEDs in Device tree is documented in [4], in "flash-leds" property
+documentation. In short, LEDs are directly referred to by using phandles.
+
+While Device tree allows referring to any node in the tree[1], in ACPI
+references are limited to device nodes only [2]. For this reason using the same
+mechanism on ACPI is not possible. A mechanism to refer to non-device ACPI nodes
+is documented in [7].
+
+ACPI allows (as does DT) using integer arguments after the reference. A
+combination of the LED driver device reference and an integer argument,
+referring to the "reg" property of the relevant LED, is used to identify
+individual LEDs. The value of the "reg" property is a contract between the
+firmware and software, it uniquely identifies the LED driver outputs.
+
+Under the LED driver device, The first hierarchical data extension package list
+entry shall contain the string "led@" followed by the number of the LED,
+followed by the referred object name. That object shall be named "LED" followed
+by the number of the LED.
+
+An ASL example of a camera sensor device and a LED driver device for two LEDs.
+Objects not relevant for LEDs or the references to them have been omitted.
+
+ Device (LED)
+ {
+ Name (_DSD, Package () {
+ ToUUID("dbb8e3e6-5886-4ba6-8795-1319f52a966b"),
+ Package () {
+ Package () { "led@0", LED0 },
+ Package () { "led@1", LED1 },
+ }
+ })
+ Name (LED0, Package () {
+ ToUUID("daffd814-6eba-4d8c-8a91-bc9bbf4aa301"),
+ Package () {
+ Package () { "reg", 0 },
+ Package () { "flash-max-microamp", 1000000 },
+ Package () { "flash-timeout-us", 200000 },
+ Package () { "led-max-microamp", 100000 },
+ Package () { "label", "white:flash" },
+ }
+ })
+ Name (LED1, Package () {
+ ToUUID("daffd814-6eba-4d8c-8a91-bc9bbf4aa301"),
+ Package () {
+ Package () { "reg", 1 },
+ Package () { "led-max-microamp", 10000 },
+ Package () { "label", "red:indicator" },
+ }
+ })
+ }
+
+ Device (SEN)
+ {
+ Name (_DSD, Package () {
+ ToUUID("daffd814-6eba-4d8c-8a91-bc9bbf4aa301"),
+ Package () {
+ Package () {
+ "flash-leds",
+ Package () { ^LED, "led@0", ^LED, "led@1" },
+ }
+ }
+ })
+ }
+
+where
+
+ LED LED driver device
+ LED0 First LED
+ LED1 Second LED
+ SEN Camera sensor device (or another device the LED is
+ related to)
+
+[1] Device tree. <URL:http://www.devicetree.org>, referenced 2019-02-21.
+
+[2] Advanced Configuration and Power Interface Specification.
+ <URL:https://uefi.org/sites/default/files/resources/ACPI_6_3_final_Jan30.pdf>,
+ referenced 2019-02-21.
+
+[3] Documentation/devicetree/bindings/leds/common.txt
+
+[4] Documentation/devicetree/bindings/media/video-interfaces.txt
+
+[5] Device Properties UUID For _DSD.
+ <URL:http://www.uefi.org/sites/default/files/resources/_DSD-device-properties-UUID.pdf>,
+ referenced 2019-02-21.
+
+[6] Hierarchical Data Extension UUID For _DSD.
+ <URL:http://www.uefi.org/sites/default/files/resources/_DSD-hierarchical-data-extension-UUID-v1.1.pdf>,
+ referenced 2019-02-21.
+
+[7] Documentation/acpi/dsd/data-node-reference.txt
diff --git a/Documentation/devicetree/bindings/leds/leds-lm3532.txt b/Documentation/devicetree/bindings/leds/leds-lm3532.txt
new file mode 100644
index 000000000000..c087f85ddddc
--- /dev/null
+++ b/Documentation/devicetree/bindings/leds/leds-lm3532.txt
@@ -0,0 +1,101 @@
+* Texas Instruments - lm3532 White LED driver with ambient light sensing
+capability.
+
+The LM3532 provides the 3 high-voltage, low-side current sinks. The device is
+programmable over an I2C-compatible interface and has independent
+current control for all three channels. The adaptive current regulation
+method allows for different LED currents in each current sink thus allowing
+for a wide variety of backlight and keypad applications.
+
+The main features of the LM3532 include dual ambient light sensor inputs
+each with 32 internal voltage setting resistors, 8-bit logarithmic and linear
+brightness control, dual external PWM brightness control inputs, and up to
+1000:1 dimming ratio with programmable fade in and fade out settings.
+
+Required properties:
+ - compatible : "ti,lm3532"
+ - reg : I2C slave address
+ - #address-cells : 1
+ - #size-cells : 0
+
+Optional properties:
+ - enable-gpios : gpio pin to enable (active high)/disable the device.
+ - ramp-up-us - The Run time ramp rates/step are from one current
+ set-point to another after the device has reached its
+ initial target set point from turn-on
+ - ramp-down-us - The Run time ramp rates/step are from one current
+ set-point to another after the device has reached its
+ initial target set point from turn-on
+ Range for ramp settings: 8us - 65536us
+
+Optional properties if ALS mode is used:
+ - ti,als-vmin - Minimum ALS voltage defined in Volts
+ - ti,als-vmax - Maximum ALS voltage defined in Volts
+ Per the data sheet the max ALS voltage is 2V and the min is 0V
+
+ - ti,als1-imp-sel - ALS1 impedance resistor selection in Ohms
+ - ti,als2-imp-sel - ALS2 impedance resistor selection in Ohms
+ Range for impedance select: 37000 Ohms - 1190 Ohms
+ Values above 37kohms will be set to the "High Impedance" setting
+
+ - ti,als-avrg-time-us - Determines the length of time the device needs to
+ average the two ALS inputs. This is only used if
+ the input mode is LM3532_ALS_INPUT_AVRG.
+ Range: 17920us - 2293760us
+ - ti,als-input-mode - Determines how the device uses the attached ALS
+ devices.
+ 0x00 - ALS1 and ALS2 input average
+ 0x01 - ALS1 Input
+ 0x02 - ALS2 Input
+ 0x03 - Max of ALS1 and ALS2
+
+Required child properties:
+ - reg : Indicates control bank the LED string is controlled by
+ - led-sources : see Documentation/devicetree/bindings/leds/common.txt
+ - ti,led-mode : Defines if the LED strings are manually controlled or
+ if the LED strings are controlled by the ALS.
+ 0x00 - LED strings are I2C controlled via full scale
+ brightness control register
+ 0x01 - LED strings are ALS controlled
+
+Optional LED child properties:
+ - label : see Documentation/devicetree/bindings/leds/common.txt
+ - linux,default-trigger :
+ see Documentation/devicetree/bindings/leds/common.txt
+
+Example:
+led-controller@38 {
+ compatible = "ti,lm3532";
+ #address-cells = <1>;
+ #size-cells = <0>;
+ reg = <0x38>;
+
+ enable-gpios = <&gpio6 12 GPIO_ACTIVE_HIGH>;
+ ramp-up-us = <1024>;
+ ramp-down-us = <65536>;
+
+ ti,als-vmin = <0>;
+ ti,als-vmax = <2000>;
+ ti,als1-imp-sel = <4110>;
+ ti,als2-imp-sel = <2180>;
+ ti,als-avrg-time-us = <17920>;
+ ti,als-input-mode = <0x00>;
+
+ led@0 {
+ reg = <0>;
+ led-sources = <2>;
+ ti,led-mode = <1>;
+ label = ":backlight";
+ linux,default-trigger = "backlight";
+ };
+
+ led@1 {
+ reg = <1>;
+ led-sources = <1>;
+ ti,led-mode = <0>;
+ label = ":kbd_backlight";
+ };
+};
+
+For more product information please see the links below:
+http://www.ti.com/product/LM3532
diff --git a/Documentation/devicetree/bindings/mfd/ti-lmu.txt b/Documentation/devicetree/bindings/mfd/ti-lmu.txt
index c885cf89b8ce..980394d701a7 100644
--- a/Documentation/devicetree/bindings/mfd/ti-lmu.txt
+++ b/Documentation/devicetree/bindings/mfd/ti-lmu.txt
@@ -4,7 +4,6 @@ TI LMU driver supports lighting devices below.
Name Child nodes
------ ---------------------------------
- LM3532 Backlight
LM3631 Backlight and regulator
LM3632 Backlight and regulator
LM3633 Backlight, LED and fault monitor
@@ -13,7 +12,6 @@ TI LMU driver supports lighting devices below.
Required properties:
- compatible: Should be one of:
- "ti,lm3532"
"ti,lm3631"
"ti,lm3632"
"ti,lm3633"
@@ -23,7 +21,6 @@ Required properties:
0x11 for LM3632
0x29 for LM3631
0x36 for LM3633, LM3697
- 0x38 for LM3532
0x63 for LM3695
Optional property:
@@ -47,23 +44,6 @@ Optional nodes:
[2] ../leds/leds-lm3633.txt
[3] ../regulator/lm363x-regulator.txt
-lm3532@38 {
- compatible = "ti,lm3532";
- reg = <0x38>;
-
- enable-gpios = <&pioC 2 GPIO_ACTIVE_HIGH>;
-
- backlight {
- compatible = "ti,lm3532-backlight";
-
- lcd {
- led-sources = <0 1 2>;
- ramp-up-msec = <30>;
- ramp-down-msec = <0>;
- };
- };
-};
-
lm3631@29 {
compatible = "ti,lm3631";
reg = <0x29>;