1 files changed, 88 insertions, 8 deletions

diff --git a/drivers/hwmon/pmbus/ibm-cffps.c b/drivers/hwmon/pmbus/ibm-cffps.c
index 2d6f4f41e736..93d9a9ea112b 100644
--- a/drivers/hwmon/pmbus/ibm-cffps.c
+++ b/drivers/hwmon/pmbus/ibm-cffps.c
@@ -13,6 +13,7 @@
 #include <linux/fs.h>
 #include <linux/i2c.h>
 #include <linux/jiffies.h>
+#include <linux/leds.h>
 #include <linux/module.h>
 #include <linux/mutex.h>
 #include <linux/pmbus.h>
@@ -25,6 +26,7 @@
 #define CFFPS_CCIN_CMD				0xBD
 #define CFFPS_FW_CMD_START			0xFA
 #define CFFPS_FW_NUM_BYTES			4
+#define CFFPS_SYS_CONFIG_CMD			0xDA
 
 #define CFFPS_INPUT_HISTORY_CMD			0xD6
 #define CFFPS_INPUT_HISTORY_SIZE		100
@@ -39,6 +41,11 @@
 #define CFFPS_MFR_VAUX_FAULT			BIT(6)
 #define CFFPS_MFR_CURRENT_SHARE_WARNING		BIT(7)
 
+#define CFFPS_LED_BLINK				BIT(0)
+#define CFFPS_LED_ON				BIT(1)
+#define CFFPS_LED_OFF				BIT(2)
+#define CFFPS_BLINK_RATE_MS			250
+
 enum {
 	CFFPS_DEBUGFS_INPUT_HISTORY = 0,
 	CFFPS_DEBUGFS_FRU,
@@ -63,6 +70,10 @@ struct ibm_cffps {
 	struct ibm_cffps_input_history input_history;
 
 	int debugfs_entries[CFFPS_DEBUGFS_NUM_ENTRIES];
+
+	char led_name[32];
+	u8 led_state;
+	struct led_classdev led;
 };
 
 #define to_psu(x, y) container_of((x), struct ibm_cffps, debugfs_entries[(y)])
@@ -258,6 +269,69 @@ static int ibm_cffps_read_word_data(struct i2c_client *client, int page,
 	return rc;
 }
 
+static void ibm_cffps_led_brightness_set(struct led_classdev *led_cdev,
+					 enum led_brightness brightness)
+{
+	int rc;
+	struct ibm_cffps *psu = container_of(led_cdev, struct ibm_cffps, led);
+
+	if (brightness == LED_OFF) {
+		psu->led_state = CFFPS_LED_OFF;
+	} else {
+		brightness = LED_FULL;
+		if (psu->led_state != CFFPS_LED_BLINK)
+			psu->led_state = CFFPS_LED_ON;
+	}
+
+	rc = i2c_smbus_write_byte_data(psu->client, CFFPS_SYS_CONFIG_CMD,
+				       psu->led_state);
+	if (rc < 0)
+		return;
+
+	led_cdev->brightness = brightness;
+}
+
+static int ibm_cffps_led_blink_set(struct led_classdev *led_cdev,
+				   unsigned long *delay_on,
+				   unsigned long *delay_off)
+{
+	int rc;
+	struct ibm_cffps *psu = container_of(led_cdev, struct ibm_cffps, led);
+
+	psu->led_state = CFFPS_LED_BLINK;
+
+	if (led_cdev->brightness == LED_OFF)
+		return 0;
+
+	rc = i2c_smbus_write_byte_data(psu->client, CFFPS_SYS_CONFIG_CMD,
+				       CFFPS_LED_BLINK);
+	if (rc < 0)
+		return rc;
+
+	*delay_on = CFFPS_BLINK_RATE_MS;
+	*delay_off = CFFPS_BLINK_RATE_MS;
+
+	return 0;
+}
+
+static void ibm_cffps_create_led_class(struct ibm_cffps *psu)
+{
+	int rc;
+	struct i2c_client *client = psu->client;
+	struct device *dev = &client->dev;
+
+	snprintf(psu->led_name, sizeof(psu->led_name), "%s-%02x", client->name,
+		 client->addr);
+	psu->led.name = psu->led_name;
+	psu->led.max_brightness = LED_FULL;
+	psu->led.brightness_set = ibm_cffps_led_brightness_set;
+	psu->led.blink_set = ibm_cffps_led_blink_set;
+
+	rc = devm_led_classdev_register(dev, &psu->led);
+	if (rc)
+		dev_warn(dev, "failed to register led class: %d\n", rc);
+}
+
 static struct pmbus_driver_info ibm_cffps_info = {
 	.pages = 1,
 	.func[0] = PMBUS_HAVE_VIN | PMBUS_HAVE_VOUT | PMBUS_HAVE_IOUT |
@@ -286,6 +360,20 @@ static int ibm_cffps_probe(struct i2c_client *client,
 	if (rc)
 		return rc;
 
+	/*
+	 * Don't fail the probe if there isn't enough memory for leds and
+	 * debugfs.
+	 */
+	psu = devm_kzalloc(&client->dev, sizeof(*psu), GFP_KERNEL);
+	if (!psu)
+		return 0;
+
+	psu->client = client;
+	mutex_init(&psu->input_history.update_lock);
+	psu->input_history.last_update = jiffies - HZ;
+
+	ibm_cffps_create_led_class(psu);
+
 	/* Don't fail the probe if we can't create debugfs */
 	debugfs = pmbus_get_debugfs_dir(client);
 	if (!debugfs)
@@ -295,14 +383,6 @@ static int ibm_cffps_probe(struct i2c_client *client,
 	if (!ibm_cffps_dir)
 		return 0;
 
-	psu = devm_kzalloc(&client->dev, sizeof(*psu), GFP_KERNEL);
-	if (!psu)
-		return 0;
-
-	psu->client = client;
-	mutex_init(&psu->input_history.update_lock);
-	psu->input_history.last_update = jiffies - HZ;
-
 	for (i = 0; i < CFFPS_DEBUGFS_NUM_ENTRIES; ++i)
 		psu->debugfs_entries[i] = i;