[PATCH 08/17] staging: muc-wmi: add brightness and color for NUC6 API

From: Mauro Carvalho Chehab
Date: Sun May 16 2021 - 06:54:19 EST


The NUC6 WMI API is really simple: it has just 2 messages,
that retrieves everything for a LED, and it has just 2 LEDs.

Add support for retrieving and set brightness and color.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@xxxxxxxxxx>
---
drivers/staging/nuc-led/nuc-wmi.c | 198 ++++++++++++++++++++++++++++--
1 file changed, 191 insertions(+), 7 deletions(-)

diff --git a/drivers/staging/nuc-led/nuc-wmi.c b/drivers/staging/nuc-led/nuc-wmi.c
index db38c40c223a..a365a8603182 100644
--- a/drivers/staging/nuc-led/nuc-wmi.c
+++ b/drivers/staging/nuc-led/nuc-wmi.c
@@ -302,14 +302,13 @@ static int nuc_wmi_query_leds_nuc6(struct device *dev)
{
// FIXME: add a check for the specific models that are known to work
struct nuc_wmi *priv = dev_get_drvdata(dev);
- u8 cmd, input[NUM_INPUT_ARGS] = { 0 };
+ u8 input[NUM_INPUT_ARGS] = { 0 };
u8 output[NUM_OUTPUT_ARGS];
struct nuc_nmi_led *led;
int ret;

- cmd = LED_OLD_GET_STATUS;
input[0] = LED_OLD_GET_S0_POWER;
- ret = nuc_nmi_cmd(dev, cmd, input, output);
+ ret = nuc_nmi_cmd(dev, LED_OLD_GET_STATUS, input, output);
if (ret) {
dev_warn(dev, "Get S0 Power: error %d\n", ret);
return ret;
@@ -322,9 +321,8 @@ static int nuc_wmi_query_leds_nuc6(struct device *dev)
led->indicator = fls(led->avail_indicators);
priv->num_leds++;

- cmd = LED_OLD_GET_STATUS;
input[0] = LED_OLD_GET_S0_RING;
- ret = nuc_nmi_cmd(dev, cmd, input, output);
+ ret = nuc_nmi_cmd(dev, LED_OLD_GET_STATUS, input, output);
if (ret) {
dev_warn(dev, "Get S0 Ring: error %d\n", ret);
return ret;
@@ -544,6 +542,167 @@ static ssize_t nuc_wmi_set_brightness_offset(struct device *dev,
} \
static DEVICE_ATTR(_name, 0644, show_##_name, store_##_name)

+/*
+ * NUC6 specific logic
+ */
+
+static int nuc_wmi_nuc6_led_get_set(struct device *dev,
+ struct nuc_nmi_led *led, int *brightness,
+ int *blink_fade, int *color_state)
+{
+ u8 input[NUM_INPUT_ARGS] = { 0 };
+ u8 output[NUM_OUTPUT_ARGS];
+ int ret;
+
+ if (led->id == POWER_LED)
+ input[0] = LED_OLD_GET_S0_POWER;
+ else
+ input[0] = LED_OLD_GET_S0_RING;
+
+ ret = nuc_nmi_cmd(dev, LED_OLD_GET_STATUS, input, output);
+ if (ret) {
+ dev_warn(dev, "Get %s: error %d\n", led_names[led->id], ret);
+ return ret;
+ }
+
+ if (brightness && *brightness >= 0)
+ input[1] = *brightness;
+ else
+ input[1] = output[0];
+
+ if (blink_fade && *blink_fade >= 0)
+ input[2] = *blink_fade;
+ else
+ input[2] = output[1];
+
+ if (color_state && *color_state >= 0)
+ input[3] = *color_state;
+ else
+ input[3] = output[2];
+
+ ret = nuc_nmi_cmd(dev, LED_OLD_SET_LED, input, output);
+ if (ret) {
+ dev_warn(dev, "Get %s: error %d\n", led_names[led->id], ret);
+ return ret;
+ }
+
+ if (brightness)
+ *brightness = output[0];
+ if (blink_fade)
+ *blink_fade = output[1];
+ if (color_state)
+ *color_state = output[2];
+
+ return 0;
+}
+
+static enum led_brightness nuc_wmi_nuc6_get_brightness(struct led_classdev *cdev)
+{
+ struct nuc_nmi_led *led = container_of(cdev, struct nuc_nmi_led, cdev);
+ int ret, brightness = -1;
+
+ ret = nuc_wmi_nuc6_led_get_set(cdev->dev, led, &brightness, NULL, NULL);
+ if (ret)
+ return ret;
+
+ return brightness;
+}
+
+static int nuc_wmi_nuc6_set_brightness(struct led_classdev *cdev,
+ enum led_brightness bright)
+{
+ int brightness = bright;
+ struct nuc_nmi_led *led = container_of(cdev, struct nuc_nmi_led, cdev);
+
+ return nuc_wmi_nuc6_led_get_set(cdev->dev, led, &brightness,
+ NULL, NULL);
+}
+
+static const char * const nuc6_power_colors[] = {
+ "disable",
+ "blue",
+ "amber"
+};
+
+static const char * const nuc6_ring_colors[] = {
+ "disable",
+ "cyan",
+ "pink",
+ "yellow",
+ "blue",
+ "red",
+ "green",
+ "white"
+};
+
+static ssize_t nuc6_show_color(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct led_classdev *cdev = dev_get_drvdata(dev);
+ struct nuc_nmi_led *led = container_of(cdev, struct nuc_nmi_led, cdev);
+ int color = -1, ret, arr_size, i, n;
+ const char * const*color_names;
+ int size = PAGE_SIZE;
+ char *p = buf;
+
+ ret = nuc_wmi_nuc6_led_get_set(dev, led, NULL, NULL, &color);
+ if (ret)
+ return ret;
+
+ if (led->id == POWER_LED) {
+ color_names = nuc6_power_colors;
+ arr_size = ARRAY_SIZE(nuc6_power_colors);
+ } else {
+ color_names = nuc6_ring_colors;
+ arr_size = ARRAY_SIZE(nuc6_ring_colors);
+ }
+
+ for (i = 0; i < arr_size; i++) {
+ if (i == color)
+ n = scnprintf(p, size, "[%s] ", color_names[i]);
+ else
+ n = scnprintf(p, size, "%s ", color_names[i]);
+ p += n;
+ size -= n;
+ }
+ size -= scnprintf(p, size, "\n");
+
+ return PAGE_SIZE - size;
+
+}
+
+static ssize_t nuc6_store_color(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t len)
+{
+ struct led_classdev *cdev = dev_get_drvdata(dev);
+ struct nuc_nmi_led *led = container_of(cdev, struct nuc_nmi_led, cdev);
+ const char *tmp;
+ int ret, color;
+
+ tmp = strsep((char **)&buf, ",\n");
+
+ if (led->id == POWER_LED) {
+ for (color = ARRAY_SIZE(nuc6_power_colors)+1; color >= 0; color--)
+ if (!strcasecmp(tmp, nuc6_power_colors[color]))
+ break;
+ } else {
+ for (color = ARRAY_SIZE(nuc6_ring_colors)+1; color >= 0; color--)
+ if (!strcasecmp(tmp, nuc6_ring_colors[color]))
+ break;
+ }
+
+ if (color < 0)
+ return -EINVAL;
+
+ ret = nuc_wmi_nuc6_led_get_set(dev, led, NULL, NULL, &color);
+ if (ret)
+ return ret;
+
+ return len;
+}
+
/* Show/change the LED indicator */

static const char * const led_indicators[] = {
@@ -657,6 +816,9 @@ static ssize_t show_color(struct device *dev,
char *p = buf;
int color, r, g, b;

+ if (led->api_rev == LED_API_NUC6)
+ return nuc6_show_color(dev, attr, buf);
+
if (led->indicator == LED_IND_DISABLE)
return -ENODEV;

@@ -723,6 +885,9 @@ static ssize_t store_color(struct device *dev,
const char *tmp;
u8 r, g, b, val;

+ if (led->api_rev == LED_API_NUC6)
+ return nuc6_store_color(dev, attr, buf, len);
+
if (led->indicator == LED_IND_DISABLE)
return -ENODEV;

@@ -825,6 +990,9 @@ static umode_t nuc_wmi_led_color_is_visible(struct kobject *kobj,
struct nuc_nmi_led *led = container_of(cdev, struct nuc_nmi_led, cdev);
umode_t mode = attr->mode;

+ if (led->api_rev == LED_API_NUC6)
+ return mode;
+
if (led->color_type & LED_SINGLE_COLOR)
return 0;

@@ -978,17 +1146,33 @@ static const struct attribute_group *nuc_wmi_led_attribute_groups[] = {
NULL
};

+static const struct attribute_group *nuc_wmi_nuc6_led_attribute_groups[] = {
+ &nuc_wmi_led_color_attribute_group,
+ NULL
+};
+
static int nuc_wmi_led_register(struct device *dev, struct nuc_nmi_led *led,
enum led_api_rev api_rev)
{
- int brightness;
+ int ret, brightness;

led->cdev.name = led_names[led->id];
led->dev = dev;
led->api_rev = api_rev;

if (led->api_rev == LED_API_NUC6) {
- // FIXME: add NUC6-specific API bits here
+ brightness = -1;
+ ret = nuc_wmi_nuc6_led_get_set(dev, led, &brightness,
+ NULL, NULL);
+ if (ret)
+ return ret;
+
+ led->cdev.groups = nuc_wmi_nuc6_led_attribute_groups;
+ led->cdev.delayed_set_value = brightness;
+ led->cdev.max_brightness = 100;
+ led->cdev.brightness_get = nuc_wmi_nuc6_get_brightness;
+ led->cdev.brightness_set_blocking = nuc_wmi_nuc6_set_brightness;
+
return devm_led_classdev_register(dev, &led->cdev);
}

--
2.31.1