Add System76 ACPI driver, which adds support for Fn-Fx key
combinations, keyboard backlight, and airplane mode LEDs
on System76 laptops running open source firmware.
Signed-off-by: Jeremy Soller <jeremy@xxxxxxxxxxxx>
Cc: platform-driver-x86@xxxxxxxxxxxxxxx
Cc: Andy Shevchenko <andy.shevchenko@xxxxxxxxx>
---
MAINTAINERS | 7 +
drivers/platform/x86/Kconfig | 13 ++
drivers/platform/x86/Makefile | 1 +
drivers/platform/x86/system76_acpi.c | 384 +++++++++++++++++++++++++++++++++++
4 files changed, 405 insertions(+)
diff --git a/MAINTAINERS b/MAINTAINERS
index a97f1be63b9d..6be3944b1b2f 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -15745,6 +15745,13 @@ F: drivers/hwtracing/stm/
F: include/linux/stm.h
F: include/uapi/linux/stm.h
+SYSTEM76 ACPI DRIVER
+M: Jeremy Soller <jeremy@xxxxxxxxxxxx>
+M: System76 Product Development <productdev@xxxxxxxxxxxx>
+L: platform-driver-x86@xxxxxxxxxxxxxxx
+S: Maintained
+F: drivers/platform/x86/system76_acpi.c
+
SYSV FILESYSTEM
M: Christoph Hellwig <hch@xxxxxxxxxxxxx>
S: Maintained
diff --git a/drivers/platform/x86/Kconfig b/drivers/platform/x86/Kconfig
index ae21d08c65e8..b880b051e3e8 100644
--- a/drivers/platform/x86/Kconfig
+++ b/drivers/platform/x86/Kconfig
@@ -1337,6 +1337,19 @@ config PCENGINES_APU2
source "drivers/platform/x86/intel_speed_select_if/Kconfig"
+config SYSTEM76_ACPI
+ tristate "System76 ACPI Driver"
+ depends on ACPI
+ select NEW_LEDS
+ select LEDS_CLASS
+ select LEDS_TRIGGERS
+ help
+ This is a driver for System76 laptops running open firmware. It adds
+ support for Fn-Fx key combinations, keyboard backlight, and airplane mode
+ LEDs.
+
+ If you have a System76 laptop running open firmware, say Y or M here.
+
endif # X86_PLATFORM_DEVICES
config PMC_ATOM
diff --git a/drivers/platform/x86/Makefile b/drivers/platform/x86/Makefile
index 415104033060..92ce1d87c4cb 100644
--- a/drivers/platform/x86/Makefile
+++ b/drivers/platform/x86/Makefile
@@ -100,3 +100,4 @@ obj-$(CONFIG_I2C_MULTI_INSTANTIATE) += i2c-multi-instantiate.o
obj-$(CONFIG_INTEL_ATOMISP2_PM) += intel_atomisp2_pm.o
obj-$(CONFIG_PCENGINES_APU2) += pcengines-apuv2.o
obj-$(CONFIG_INTEL_SPEED_SELECT_INTERFACE) += intel_speed_select_if/
+obj-$(CONFIG_SYSTEM76_ACPI) += system76_acpi.o
diff --git a/drivers/platform/x86/system76_acpi.c b/drivers/platform/x86/system76_acpi.c
new file mode 100644
index 000000000000..4f6e4c342382
--- /dev/null
+++ b/drivers/platform/x86/system76_acpi.c
@@ -0,0 +1,384 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * System76 ACPI Driver
+ *
+ * Copyright (C) 2019 System76
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/acpi.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/leds.h>
+#include <linux/module.h>
+#include <linux/pci_ids.h>
+#include <linux/types.h>
+
+struct system76_data {
+ struct acpi_device *acpi_dev;
+ struct led_classdev ap_led;
+ struct led_classdev kb_led;
+ enum led_brightness kb_brightness;
+ enum led_brightness kb_toggle_brightness;
+ int kb_color;
+};
+
+static const struct acpi_device_id device_ids[] = {
+ {"17761776", 0},
+ {"", 0},
+};
+MODULE_DEVICE_TABLE(acpi, device_ids);
+
+// Array of keyboard LED brightness levels
+static const enum led_brightness kb_levels[] = {
+ 48,
+ 72,
+ 96,
+ 144,
+ 192,
+ 255
+};
+
+// Array of keyboard LED colors in 24-bit RGB format
+static const int kb_colors[] = {
+ 0xFFFFFF,
+ 0x0000FF,
+ 0xFF0000,
+ 0xFF00FF,
+ 0x00FF00,
+ 0x00FFFF,
+ 0xFFFF00
+};
+
+// Get a System76 ACPI device value by name
+static int system76_get(struct system76_data *data, char *method)
+{
+ acpi_handle handle;
+ acpi_status status;
+ unsigned long long ret = 0;
+
+ handle = acpi_device_handle(data->acpi_dev);
+ status = acpi_evaluate_integer(handle, method, NULL, &ret);
+ if (ACPI_SUCCESS(status))
+ return (int)ret;
+ else
+ return -1;
+}
+
+// Set a System76 ACPI device value by name
+static int system76_set(struct system76_data *data, char *method, int value)
+{
+ union acpi_object obj;
+ struct acpi_object_list obj_list;
+ acpi_handle handle;
+ acpi_status status;
+
+ obj.type = ACPI_TYPE_INTEGER;
+ obj.integer.value = value;
+ obj_list.count = 1;
+ obj_list.pointer = &obj;
+ handle = acpi_device_handle(data->acpi_dev);
+ status = acpi_evaluate_object(handle, method, &obj_list, NULL);
+ if (ACPI_SUCCESS(status))
+ return 0;
+ else
+ return -1;
+}
+
+// Get the airplane mode LED brightness
+static enum led_brightness ap_led_get(struct led_classdev *led)
+{
+ struct system76_data *data;
+ int value;
+
+ data = container_of(led, struct system76_data, ap_led);
+ value = system76_get(data, "GAPL");
+ if (value > 0)
+ return (enum led_brightness)value;
+ else
+ return LED_OFF;
+}
+
+// Set the airplane mode LED brightness
+static void ap_led_set(struct led_classdev *led, enum led_brightness value)
+{
+ struct system76_data *data;
+
+ data = container_of(led, struct system76_data, ap_led);
+ system76_set(data, "SAPL", value == LED_OFF ? 0 : 1);
+}
+
+// Get the last set keyboard LED brightness
+static enum led_brightness kb_led_get(struct led_classdev *led)
+{
+ struct system76_data *data;
+
+ data = container_of(led, struct system76_data, kb_led);
+ return data->kb_brightness;
+}
+
+// Set the keyboard LED brightness
+static void kb_led_set(struct led_classdev *led, enum led_brightness value)
+{
+ struct system76_data *data;
+
+ data = container_of(led, struct system76_data, kb_led);
+ data->kb_brightness = value;
+ system76_set(data, "SKBL", (int)data->kb_brightness);
+}
+
+// Get the last set keyboard LED color
+static ssize_t kb_led_color_show(
+ struct device *dev,
+ struct device_attribute *dev_attr,
+ char *buf)
+{
+ struct led_classdev *led;
+ struct system76_data *data;
+
+ led = (struct led_classdev *)dev->driver_data;
+ data = container_of(led, struct system76_data, kb_led);
+ return sprintf(buf, "%06X\n", data->kb_color);
+}
+
+// Set the keyboard LED color
+static ssize_t kb_led_color_store(
+ struct device *dev,
+ struct device_attribute *dev_attr,
+ const char *buf,
+ size_t size)
+{
+ struct led_classdev *led;
+ struct system76_data *data;
+ unsigned int val;
+ int ret;
+
+ led = (struct led_classdev *)dev->driver_data;
+ data = container_of(led, struct system76_data, kb_led);
+ ret = kstrtouint(buf, 16, &val);
+ if (ret)
+ return ret;
+ if (val > 0xFFFFFF)
+ return -EINVAL;
+ data->kb_color = (int)val;
+ system76_set(data, "SKBC", data->kb_color);
+
+ return size;
+}
+
+static const struct device_attribute kb_led_color_dev_attr = {
+ .attr = {
+ .name = "color",
+ .mode = 0644,
+ },
+ .show = kb_led_color_show,
+ .store = kb_led_color_store,
+};
+
+// Notify that the keyboard LED was changed by hardware
+static void kb_led_notify(struct system76_data *data)
+{
+ led_classdev_notify_brightness_hw_changed(
+ &data->kb_led,
+ data->kb_brightness
+ );
+}
+
+// Read keyboard LED brightness as set by hardware
+static void kb_led_hotkey_hardware(struct system76_data *data)
+{
+ int value;
+
+ value = system76_get(data, "GKBL");
+ if (value < 0)
+ return;
+ data->kb_brightness = value;
+ kb_led_notify(data);
+}
+
+// Toggle the keyboard LED
+static void kb_led_hotkey_toggle(struct system76_data *data)
+{
+ if (data->kb_brightness > 0) {
+ data->kb_toggle_brightness = data->kb_brightness;
+ kb_led_set(&data->kb_led, 0);
+ } else {
+ kb_led_set(&data->kb_led, data->kb_toggle_brightness);
+ }
+ kb_led_notify(data);
+}
+
+// Decrease the keyboard LED brightness
+static void kb_led_hotkey_down(struct system76_data *data)
+{
+ int i;
+
+ if (data->kb_brightness > 0) {
+ for (i = ARRAY_SIZE(kb_levels); i > 0; i--) {
+ if (kb_levels[i - 1] < data->kb_brightness) {
+ kb_led_set(&data->kb_led, kb_levels[i - 1]);
+ break;
+ }
+ }
+ } else {
+ kb_led_set(&data->kb_led, data->kb_toggle_brightness);
+ }
+ kb_led_notify(data);
+}
+
+// Increase the keyboard LED brightness
+static void kb_led_hotkey_up(struct system76_data *data)
+{
+ int i;
+
+ if (data->kb_brightness > 0) {
+ for (i = 0; i < ARRAY_SIZE(kb_levels); i++) {
+ if (kb_levels[i] > data->kb_brightness) {
+ kb_led_set(&data->kb_led, kb_levels[i]);
+ break;
+ }
+ }
+ } else {
+ kb_led_set(&data->kb_led, data->kb_toggle_brightness);
+ }
+ kb_led_notify(data);
+}
+
+// Cycle the keyboard LED color
+static void kb_led_hotkey_color(struct system76_data *data)
+{
+ int i;
+
+ if (data->kb_color < 0)
+ return;
+ if (data->kb_brightness > 0) {
+ for (i = 0; i < ARRAY_SIZE(kb_colors); i++) {
+ if (kb_colors[i] == data->kb_color)
+ break;
+ }
+ i += 1;
+ if (i >= ARRAY_SIZE(kb_colors))
+ i = 0;
+ data->kb_color = kb_colors[i];
+ system76_set(data, "SKBC", data->kb_color);
+ } else {
+ kb_led_set(&data->kb_led, data->kb_toggle_brightness);
+ }
+ kb_led_notify(data);
+}
+
+// Handle ACPI notification
+static void system76_notify(struct acpi_device *acpi_dev, u32 event)
+{
+ struct system76_data *data;
+
+ data = acpi_driver_data(acpi_dev);
+ switch (event) {
+ case 0x80:
+ kb_led_hotkey_hardware(data);
+ break;
+ case 0x81:
+ kb_led_hotkey_toggle(data);
+ break;
+ case 0x82:
+ kb_led_hotkey_down(data);
+ break;
+ case 0x83:
+ kb_led_hotkey_up(data);
+ break;
+ case 0x84:
+ kb_led_hotkey_color(data);
+ break;
+ }
+}
+
+// Add a System76 ACPI device
+static int system76_add(struct acpi_device *acpi_dev)
+{
+ struct system76_data *data;
+ int err;
+
+ data = devm_kzalloc(&acpi_dev->dev, sizeof(*data), GFP_KERNEL);
+ if (!data)
+ return -ENOMEM;
+ acpi_dev->driver_data = data;
+ data->acpi_dev = acpi_dev;
+
+ err = system76_get(data, "INIT");
+ if (err)
+ return err;
+ data->ap_led.name = "system76_acpi::airplane";
+ data->ap_led.flags = LED_CORE_SUSPENDRESUME;
+ data->ap_led.brightness_get = ap_led_get;
+ data->ap_led.brightness_set = ap_led_set;
+ data->ap_led.max_brightness = 1;
+ data->ap_led.default_trigger = "rfkill-none";
+ err = devm_led_classdev_register(&acpi_dev->dev, &data->ap_led);
+ if (err)
+ return err;
+
+ data->kb_led.name = "system76_acpi::kbd_backlight";
+ data->kb_led.flags = LED_BRIGHT_HW_CHANGED | LED_CORE_SUSPENDRESUME;
+ data->kb_led.brightness_get = kb_led_get;
+ data->kb_led.brightness_set = kb_led_set;
+ if (acpi_has_method(acpi_device_handle(data->acpi_dev), "SKBC")) {
+ data->kb_led.max_brightness = 255;
+ data->kb_toggle_brightness = 72;
+ data->kb_color = 0xffffff;
+ system76_set(data, "SKBC", data->kb_color);
+ } else {
+ data->kb_led.max_brightness = 5;
+ data->kb_color = -1;
+ }
+ err = devm_led_classdev_register(&acpi_dev->dev, &data->kb_led);
+ if (err)
+ return err;
+
+ if (data->kb_color >= 0) {
+ err = device_create_file(
+ data->kb_led.dev,
+ &kb_led_color_dev_attr
+ );
+ if (err)
+ return err;
+ }
+
+ return 0;
+}
+
+// Remove a System76 ACPI device
+static int system76_remove(struct acpi_device *acpi_dev)
+{
+ struct system76_data *data;
+
+ data = acpi_driver_data(acpi_dev);
+ if (data->kb_color >= 0)
+ device_remove_file(data->kb_led.dev, &kb_led_color_dev_attr);
+
+ devm_led_classdev_unregister(&acpi_dev->dev, &data->ap_led);
+
+ devm_led_classdev_unregister(&acpi_dev->dev, &data->kb_led);
+
+ system76_get(data, "FINI");
+
+ return 0;
+}
+
+static struct acpi_driver system76_driver = {
+ .name = "System76 ACPI Driver",
+ .class = "hotkey",
+ .ids = device_ids,
+ .ops = {
+ .add = system76_add,
+ .remove = system76_remove,
+ .notify = system76_notify,
+ },
+};
+module_acpi_driver(system76_driver);
+
+MODULE_DESCRIPTION("System76 ACPI Driver");
+MODULE_AUTHOR("Jeremy Soller <jeremy@xxxxxxxxxxxx>");
+MODULE_LICENSE("GPL");
