iv/linux
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

platform/chrome: cros_kbd_led_backlight: support EC PWM backend

Browse Source 
EC PWM backend uses EC_CMD_PWM_SET_KEYBOARD_BACKLIGHT and
EC_CMD_PWM_GET_KEYBOARD_BACKLIGHT for setting and getting the brightness
respectively.

Signed-off-by: Tzung-Bi Shih <tzungbi@kernel.org>
Reviewed-by: Matthias Kaehlcke <mka@chromium.org>
Tested-by: Matthias Kaehlcke <mka@chromium.org>
Link: https://lore.kernel.org/r/20220523090822.3035189-6-tzungbi@kernel.org
This commit is contained in:
Tzung-Bi Shih 2022-05-23 17:08:22 +08:00
parent fd1e8054ff
commit 40f5814374
2 changed files with 99 additions and 16 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
drivers/platform/chrome/Kconfig
View File

@ -139,7 +139,7 @@ config CROS_EC_PROTO
config CROS_KBD_LED_BACKLIGHT
tristate "Backlight LED support for Chrome OS keyboards"
depends on LEDS_CLASS && ACPI
depends on LEDS_CLASS && (ACPI || CROS_EC)
help
This option enables support for the keyboard backlight LEDs on
select Chrome OS systems.

113
drivers/platform/chrome/cros_kbd_led_backlight.c
View File

@ -11,10 +11,17 @@
#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.
@ -40,6 +47,8 @@ struct keyboard_led_drvdata {
enum led_brightness max_brightness;
};
#define KEYBOARD_BACKLIGHT_MAX 100
#ifdef CONFIG_ACPI
/* Keyboard LED ACPI Device must be defined in firmware */
@ -47,8 +56,6 @@ struct keyboard_led_drvdata {
#define ACPI_KEYBOARD_BACKLIGHT_READ ACPI_KEYBOARD_BACKLIGHT_DEVICE ".KBQC"
#define ACPI_KEYBOARD_BACKLIGHT_WRITE ACPI_KEYBOARD_BACKLIGHT_DEVICE ".KBCM"
#define ACPI_KEYBOARD_BACKLIGHT_MAX 100
static void keyboard_led_set_brightness_acpi(struct led_classdev *cdev,
enum led_brightness brightness)
{
@ -107,39 +114,114 @@ 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 = ACPI_KEYBOARD_BACKLIGHT_MAX,
.max_brightness = KEYBOARD_BACKLIGHT_MAX,
};
#endif /* CONFIG_ACPI */
#ifdef 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 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 /* CONFIG_CROS_EC */
static const struct keyboard_led_drvdata keyboard_led_drvdata_ec_pwm = {};
#endif /* CONFIG_CROS_EC */
static int keyboard_led_probe(struct platform_device *pdev)
{
struct led_classdev *cdev;
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;
}
cdev = devm_kzalloc(&pdev->dev, sizeof(*cdev), GFP_KERNEL);
if (!cdev)
return -ENOMEM;
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;
cdev->name = "chromeos::kbd_backlight";
cdev->flags |= LED_CORE_SUSPENDRESUME;
cdev->max_brightness = drvdata->max_brightness;
cdev->brightness_set = drvdata->brightness_set;
cdev->brightness_set_blocking = drvdata->brightness_set_blocking;
cdev->brightness_get = drvdata->brightness_get;
error = devm_led_classdev_register(&pdev->dev, cdev);
error = devm_led_classdev_register(&pdev->dev, &keyboard_led->cdev);
if (error)
return error;
@ -158,6 +240,7 @@ MODULE_DEVICE_TABLE(acpi, keyboard_led_acpi_match);
static const struct of_device_id keyboard_led_of_match[] = {
{
.compatible = "google,cros-kbd-led-backlight",
.data = &keyboard_led_drvdata_ec_pwm,
},
{}
};