Re: [PATCH] hwmon (pmbus): cffps: Add led class device for power supply fault led
From: Eddie James
Date: Wed Jan 10 2018 - 11:37:08 EST
On 01/09/2018 04:50 PM, Guenter Roeck wrote:
On Tue, Jan 09, 2018 at 04:05:24PM -0600, Eddie James wrote:
This power supply device doesn't correctly manage it's own fault led.
Add an led class device and register it so that userspace can manage
power supply fault led as necessary.
Signed-off-by: Eddie James <eajames@xxxxxxxxxxxxxxxxxx>
---
drivers/hwmon/pmbus/ibm-cffps.c | 90 +++++++++++++++++++++++++++++++++++++----
1 file changed, 82 insertions(+), 8 deletions(-)
diff --git a/drivers/hwmon/pmbus/ibm-cffps.c b/drivers/hwmon/pmbus/ibm-cffps.c
index 2d6f4f4..1e95dea 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 +70,9 @@ struct ibm_cffps {
struct ibm_cffps_input_history input_history;
int debugfs_entries[CFFPS_DEBUGFS_NUM_ENTRIES];
+
+ u8 led_state;
+ struct led_classdev led;
};
#define to_psu(x, y) container_of((x), struct ibm_cffps, debugfs_entries[(y)])
@@ -258,6 +268,51 @@ 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 struct pmbus_driver_info ibm_cffps_info = {
.pages = 1,
.func[0] = PMBUS_HAVE_VIN | PMBUS_HAVE_VOUT | PMBUS_HAVE_IOUT |
@@ -277,6 +332,8 @@ static int ibm_cffps_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
int i, rc;
+ char *led_name;
+ size_t name_length;
struct dentry *debugfs;
struct dentry *ibm_cffps_dir;
struct ibm_cffps *psu;
@@ -286,6 +343,31 @@ static int ibm_cffps_probe(struct i2c_client *client,
if (rc)
return rc;
+ /* client name, '-', 8 chars for addr, and null */
+ name_length = strlen(client->name) + 10;
+
+ /* Don't fail the probe if we can't create led devices */
+ psu = devm_kzalloc(&client->dev, sizeof(*psu) + name_length,
+ GFP_KERNEL);
+ if (!psu)
+ return 0;
... and no debugfs either ?
Well we need that struct allocated for debugfs as well. I'll clarify the
comment.
+
+ psu->client = client;
+ mutex_init(&psu->input_history.update_lock);
+ psu->input_history.last_update = jiffies - HZ;
+
+ led_name = (void *)(&psu[1]);
+ snprintf(led_name, name_length, "%s-%x", client->name, client->addr);
+ psu->led.name = 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(&client->dev, &psu->led);
+ if (rc)
+ dev_info(&client->dev, "failed to register led class: %d\n",
dev_warn() might be more appropriate.
Sure.
+ rc);
+
Please move the led initialization code into its own function.
Sure.
/* Don't fail the probe if we can't create debugfs */
debugfs = pmbus_get_debugfs_dir(client);
if (!debugfs)
@@ -295,14 +377,6 @@ 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;
-
unrelated ?
Thought it made sense to move it with the allocation, but I can leave it
where it is.
Thanks,
Eddie
for (i = 0; i < CFFPS_DEBUGFS_NUM_ENTRIES; ++i)
psu->debugfs_entries[i] = i;
--
1.8.3.1