hwmon: (pmbus/adm1266) add debugfs for states

Add a debugfs entry which prints the current state
of the adm1266 sequencer.

Signed-off-by: Alexandru Tachici <alexandru.tachici@analog.com>
Link: https://lore.kernel.org/r/20200812142055.9213-5-alexandru.tachici@analog.com
Signed-off-by: Guenter Roeck <linux@roeck-us.net>

diff --git a/drivers/hwmon/pmbus/adm1266.c b/drivers/hwmon/pmbus/adm1266.c
index bcc8a78..e129a88 100644 (file)
--- a/drivers/hwmon/pmbus/adm1266.c
+++ b/drivers/hwmon/pmbus/adm1266.c
@@ -19,6 +19,7 @@
 #include <linux/slab.h>
 
 #define ADM1266_PDIO_CONFIG    0xD4
+#define ADM1266_READ_STATE     0xD9
 #define ADM1266_GPIO_CONFIG    0xE1
 #define ADM1266_PDIO_STATUS    0xE9
 #define ADM1266_GPIO_STATUS    0xEA
@@ -43,6 +44,7 @@ struct adm1266_data {
        struct gpio_chip gc;
        const char *gpio_names[ADM1266_GPIO_NR + ADM1266_PDIO_NR];
        struct i2c_client *client;
+       struct dentry *debugfs_dir;
        struct mutex buf_mutex;
        u8 write_buf[ADM1266_PMBUS_BLOCK_MAX + 1] ____cacheline_aligned;
        u8 read_buf[ADM1266_PMBUS_BLOCK_MAX + 1] ____cacheline_aligned;
@@ -292,6 +294,37 @@ static int adm1266_config_gpio(struct adm1266_data *data)
        return ret;
 }
 
+static int adm1266_state_read(struct seq_file *s, void *pdata)
+{
+       struct device *dev = s->private;
+       struct i2c_client *client = to_i2c_client(dev);
+       int ret;
+
+       ret = i2c_smbus_read_word_data(client, ADM1266_READ_STATE);
+       if (ret < 0)
+               return ret;
+
+       seq_printf(s, "%d\n", ret);
+
+       return 0;
+}
+
+static void adm1266_init_debugfs(struct adm1266_data *data)
+{
+       struct dentry *root;
+
+       root = pmbus_get_debugfs_dir(data->client);
+       if (!root)
+               return;
+
+       data->debugfs_dir = debugfs_create_dir(data->client->name, root);
+       if (!data->debugfs_dir)
+               return;
+
+       debugfs_create_devm_seqfile(&data->client->dev, "sequencer_state", data->debugfs_dir,
+                                   adm1266_state_read);
+}
+
 static int adm1266_probe(struct i2c_client *client)
 {
        struct adm1266_data *data;
@@ -315,7 +348,13 @@ static int adm1266_probe(struct i2c_client *client)
        if (ret < 0)
                return ret;
 
-       return pmbus_do_probe(client, &data->info);
+       ret = pmbus_do_probe(client, &data->info);
+       if (ret)
+               return ret;
+
+       adm1266_init_debugfs(data);
+
+       return 0;
 }
 
 static const struct of_device_id adm1266_of_match[] = {