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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
commit2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch)
tree848558de17fb3008cdf4d861b01ac7781903ce39 /drivers/platform/chrome/cros_kbd_led_backlight.c
parentInitial commit. (diff)
downloadlinux-upstream.tar.xz
linux-upstream.zip
Adding upstream version 6.1.76.upstream/6.1.76upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/platform/chrome/cros_kbd_led_backlight.c')
-rw-r--r--drivers/platform/chrome/cros_kbd_led_backlight.c263
1 files changed, 263 insertions, 0 deletions
diff --git a/drivers/platform/chrome/cros_kbd_led_backlight.c b/drivers/platform/chrome/cros_kbd_led_backlight.c
new file mode 100644
index 000000000..793fd3f10
--- /dev/null
+++ b/drivers/platform/chrome/cros_kbd_led_backlight.c
@@ -0,0 +1,263 @@
+// SPDX-License-Identifier: GPL-2.0+
+// Keyboard backlight LED driver for ChromeOS
+//
+// Copyright (C) 2012 Google, Inc.
+
+#include <linux/acpi.h>
+#include <linux/delay.h>
+#include <linux/err.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/leds.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_data/cros_ec_commands.h>
+#include <linux/platform_data/cros_ec_proto.h>
+#include <linux/platform_device.h>
+#include <linux/property.h>
+#include <linux/slab.h>
+
+struct keyboard_led {
+ struct led_classdev cdev;
+ struct cros_ec_device *ec;
+};
+
+/**
+ * struct keyboard_led_drvdata - keyboard LED driver data.
+ * @init: Init function.
+ * @brightness_get: Get LED brightness level.
+ * @brightness_set: Set LED brightness level. Must not sleep.
+ * @brightness_set_blocking: Set LED brightness level. It can block the
+ * caller for the time required for accessing a
+ * LED device register
+ * @max_brightness: Maximum brightness.
+ *
+ * See struct led_classdev in include/linux/leds.h for more details.
+ */
+struct keyboard_led_drvdata {
+ int (*init)(struct platform_device *pdev);
+
+ enum led_brightness (*brightness_get)(struct led_classdev *led_cdev);
+
+ void (*brightness_set)(struct led_classdev *led_cdev,
+ enum led_brightness brightness);
+ int (*brightness_set_blocking)(struct led_classdev *led_cdev,
+ enum led_brightness brightness);
+
+ enum led_brightness max_brightness;
+};
+
+#define KEYBOARD_BACKLIGHT_MAX 100
+
+#ifdef CONFIG_ACPI
+
+/* Keyboard LED ACPI Device must be defined in firmware */
+#define ACPI_KEYBOARD_BACKLIGHT_DEVICE "\\_SB.KBLT"
+#define ACPI_KEYBOARD_BACKLIGHT_READ ACPI_KEYBOARD_BACKLIGHT_DEVICE ".KBQC"
+#define ACPI_KEYBOARD_BACKLIGHT_WRITE ACPI_KEYBOARD_BACKLIGHT_DEVICE ".KBCM"
+
+static void keyboard_led_set_brightness_acpi(struct led_classdev *cdev,
+ enum led_brightness brightness)
+{
+ union acpi_object param;
+ struct acpi_object_list input;
+ acpi_status status;
+
+ param.type = ACPI_TYPE_INTEGER;
+ param.integer.value = brightness;
+ input.count = 1;
+ input.pointer = &param;
+
+ status = acpi_evaluate_object(NULL, ACPI_KEYBOARD_BACKLIGHT_WRITE,
+ &input, NULL);
+ if (ACPI_FAILURE(status))
+ dev_err(cdev->dev, "Error setting keyboard LED value: %d\n",
+ status);
+}
+
+static enum led_brightness
+keyboard_led_get_brightness_acpi(struct led_classdev *cdev)
+{
+ unsigned long long brightness;
+ acpi_status status;
+
+ status = acpi_evaluate_integer(NULL, ACPI_KEYBOARD_BACKLIGHT_READ,
+ NULL, &brightness);
+ if (ACPI_FAILURE(status)) {
+ dev_err(cdev->dev, "Error getting keyboard LED value: %d\n",
+ status);
+ return -EIO;
+ }
+
+ return brightness;
+}
+
+static int keyboard_led_init_acpi(struct platform_device *pdev)
+{
+ acpi_handle handle;
+ acpi_status status;
+
+ /* Look for the keyboard LED ACPI Device */
+ status = acpi_get_handle(ACPI_ROOT_OBJECT,
+ ACPI_KEYBOARD_BACKLIGHT_DEVICE,
+ &handle);
+ if (ACPI_FAILURE(status)) {
+ dev_err(&pdev->dev, "Unable to find ACPI device %s: %d\n",
+ ACPI_KEYBOARD_BACKLIGHT_DEVICE, status);
+ return -ENXIO;
+ }
+
+ return 0;
+}
+
+static const struct keyboard_led_drvdata keyboard_led_drvdata_acpi = {
+ .init = keyboard_led_init_acpi,
+ .brightness_set = keyboard_led_set_brightness_acpi,
+ .brightness_get = keyboard_led_get_brightness_acpi,
+ .max_brightness = KEYBOARD_BACKLIGHT_MAX,
+};
+
+#endif /* CONFIG_ACPI */
+
+#if IS_ENABLED(CONFIG_CROS_EC)
+
+static int
+keyboard_led_set_brightness_ec_pwm(struct led_classdev *cdev,
+ enum led_brightness brightness)
+{
+ struct {
+ struct cros_ec_command msg;
+ struct ec_params_pwm_set_keyboard_backlight params;
+ } __packed buf;
+ struct ec_params_pwm_set_keyboard_backlight *params = &buf.params;
+ struct cros_ec_command *msg = &buf.msg;
+ struct keyboard_led *keyboard_led = container_of(cdev, struct keyboard_led, cdev);
+
+ memset(&buf, 0, sizeof(buf));
+
+ msg->command = EC_CMD_PWM_SET_KEYBOARD_BACKLIGHT;
+ msg->outsize = sizeof(*params);
+
+ params->percent = brightness;
+
+ return cros_ec_cmd_xfer_status(keyboard_led->ec, msg);
+}
+
+static enum led_brightness
+keyboard_led_get_brightness_ec_pwm(struct led_classdev *cdev)
+{
+ struct {
+ struct cros_ec_command msg;
+ struct ec_response_pwm_get_keyboard_backlight resp;
+ } __packed buf;
+ struct ec_response_pwm_get_keyboard_backlight *resp = &buf.resp;
+ struct cros_ec_command *msg = &buf.msg;
+ struct keyboard_led *keyboard_led = container_of(cdev, struct keyboard_led, cdev);
+ int ret;
+
+ memset(&buf, 0, sizeof(buf));
+
+ msg->command = EC_CMD_PWM_GET_KEYBOARD_BACKLIGHT;
+ msg->insize = sizeof(*resp);
+
+ ret = cros_ec_cmd_xfer_status(keyboard_led->ec, msg);
+ if (ret < 0)
+ return ret;
+
+ return resp->percent;
+}
+
+static int keyboard_led_init_ec_pwm(struct platform_device *pdev)
+{
+ struct keyboard_led *keyboard_led = platform_get_drvdata(pdev);
+
+ keyboard_led->ec = dev_get_drvdata(pdev->dev.parent);
+ if (!keyboard_led->ec) {
+ dev_err(&pdev->dev, "no parent EC device\n");
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static const __maybe_unused struct keyboard_led_drvdata keyboard_led_drvdata_ec_pwm = {
+ .init = keyboard_led_init_ec_pwm,
+ .brightness_set_blocking = keyboard_led_set_brightness_ec_pwm,
+ .brightness_get = keyboard_led_get_brightness_ec_pwm,
+ .max_brightness = KEYBOARD_BACKLIGHT_MAX,
+};
+
+#else /* IS_ENABLED(CONFIG_CROS_EC) */
+
+static const __maybe_unused struct keyboard_led_drvdata keyboard_led_drvdata_ec_pwm = {};
+
+#endif /* IS_ENABLED(CONFIG_CROS_EC) */
+
+static int keyboard_led_probe(struct platform_device *pdev)
+{
+ const struct keyboard_led_drvdata *drvdata;
+ struct keyboard_led *keyboard_led;
+ int error;
+
+ drvdata = device_get_match_data(&pdev->dev);
+ if (!drvdata)
+ return -EINVAL;
+
+ keyboard_led = devm_kzalloc(&pdev->dev, sizeof(*keyboard_led), GFP_KERNEL);
+ if (!keyboard_led)
+ return -ENOMEM;
+ platform_set_drvdata(pdev, keyboard_led);
+
+ if (drvdata->init) {
+ error = drvdata->init(pdev);
+ if (error)
+ return error;
+ }
+
+ keyboard_led->cdev.name = "chromeos::kbd_backlight";
+ keyboard_led->cdev.flags |= LED_CORE_SUSPENDRESUME;
+ keyboard_led->cdev.max_brightness = drvdata->max_brightness;
+ keyboard_led->cdev.brightness_set = drvdata->brightness_set;
+ keyboard_led->cdev.brightness_set_blocking = drvdata->brightness_set_blocking;
+ keyboard_led->cdev.brightness_get = drvdata->brightness_get;
+
+ error = devm_led_classdev_register(&pdev->dev, &keyboard_led->cdev);
+ if (error)
+ return error;
+
+ return 0;
+}
+
+#ifdef CONFIG_ACPI
+static const struct acpi_device_id keyboard_led_acpi_match[] = {
+ { "GOOG0002", (kernel_ulong_t)&keyboard_led_drvdata_acpi },
+ { }
+};
+MODULE_DEVICE_TABLE(acpi, keyboard_led_acpi_match);
+#endif
+
+#ifdef CONFIG_OF
+static const struct of_device_id keyboard_led_of_match[] = {
+ {
+ .compatible = "google,cros-kbd-led-backlight",
+ .data = &keyboard_led_drvdata_ec_pwm,
+ },
+ {}
+};
+MODULE_DEVICE_TABLE(of, keyboard_led_of_match);
+#endif
+
+static struct platform_driver keyboard_led_driver = {
+ .driver = {
+ .name = "chromeos-keyboard-leds",
+ .acpi_match_table = ACPI_PTR(keyboard_led_acpi_match),
+ .of_match_table = of_match_ptr(keyboard_led_of_match),
+ },
+ .probe = keyboard_led_probe,
+};
+module_platform_driver(keyboard_led_driver);
+
+MODULE_AUTHOR("Simon Que <sque@chromium.org>");
+MODULE_DESCRIPTION("ChromeOS Keyboard backlight LED Driver");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:chromeos-keyboard-leds");