hwmon: (pmbus/adm1275) Validate device ID

Since manufacturer and device ID are known, read and validate it.

Signed-off-by: Guenter Roeck <guenter.roeck@ericsson.com>
[Dan Carpenter <dan.carpenter@oracle.com>: Fixed memory leak]
Reviewed-by: Robert Coulson <robert.coulson@ericsson.com>

diff --git a/drivers/hwmon/pmbus/adm1275.c b/drivers/hwmon/pmbus/adm1275.c
index 980a4d9..81c7c2e 100644 (file)
--- a/drivers/hwmon/pmbus/adm1275.c
+++ b/drivers/hwmon/pmbus/adm1275.c
@@ -170,35 +170,71 @@ static int adm1275_read_byte_data(struct i2c_client *client, int page, int reg)
        return ret;
 }
 
+static const struct i2c_device_id adm1275_id[] = {
+       { "adm1275", adm1275 },
+       { "adm1276", adm1276 },
+       { }
+};
+MODULE_DEVICE_TABLE(i2c, adm1275_id);
+
 static int adm1275_probe(struct i2c_client *client,
                         const struct i2c_device_id *id)
 {
+       u8 block_buffer[I2C_SMBUS_BLOCK_MAX + 1];
        int config, device_config;
        int ret;
        struct pmbus_driver_info *info;
        struct adm1275_data *data;
+       const struct i2c_device_id *mid;
 
        if (!i2c_check_functionality(client->adapter,
-                                    I2C_FUNC_SMBUS_READ_BYTE_DATA))
+                                    I2C_FUNC_SMBUS_READ_BYTE_DATA
+                                    | I2C_FUNC_SMBUS_BLOCK_DATA))
                return -ENODEV;
 
-       data = kzalloc(sizeof(struct adm1275_data), GFP_KERNEL);
-       if (!data)
-               return -ENOMEM;
+       ret = i2c_smbus_read_block_data(client, PMBUS_MFR_ID, block_buffer);
+       if (ret < 0) {
+               dev_err(&client->dev, "Failed to read Manufacturer ID\n");
+               return ret;
+       }
+       if (ret != 3 || strncmp(block_buffer, "ADI", 3)) {
+               dev_err(&client->dev, "Unsupported Manufacturer ID\n");
+               return -ENODEV;
+       }
 
-       config = i2c_smbus_read_byte_data(client, ADM1275_PMON_CONFIG);
-       if (config < 0) {
-               ret = config;
-               goto err_mem;
+       ret = i2c_smbus_read_block_data(client, PMBUS_MFR_MODEL, block_buffer);
+       if (ret < 0) {
+               dev_err(&client->dev, "Failed to read Manufacturer Model\n");
+               return ret;
+       }
+       for (mid = adm1275_id; mid->name[0]; mid++) {
+               if (!strncasecmp(mid->name, block_buffer, strlen(mid->name)))
+                       break;
+       }
+       if (!mid->name[0]) {
+               dev_err(&client->dev, "Unsupported device\n");
+               return -ENODEV;
        }
 
+       if (id->driver_data != mid->driver_data)
+               dev_notice(&client->dev,
+                          "Device mismatch: Configured %s, detected %s\n",
+                          id->name, mid->name);
+
+       config = i2c_smbus_read_byte_data(client, ADM1275_PMON_CONFIG);
+       if (config < 0)
+               return config;
+
        device_config = i2c_smbus_read_byte_data(client, ADM1275_DEVICE_CONFIG);
-       if (device_config < 0) {
-               ret = device_config;
-               goto err_mem;
-       }
+       if (device_config < 0)
+               return device_config;
+
+       data = kzalloc(sizeof(struct adm1275_data), GFP_KERNEL);
+       if (!data)
+               return -ENOMEM;
+
+       data->id = mid->driver_data;
 
-       data->id = id->driver_data;
        info = &data->info;
 
        info->pages = 1;
@@ -233,7 +269,7 @@ static int adm1275_probe(struct i2c_client *client,
        if (device_config & ADM1275_IOUT_WARN2_SELECT)
                data->have_oc_fault = true;
 
-       switch (id->driver_data) {
+       switch (data->id) {
        case adm1275:
                if (config & ADM1275_VIN_VOUT_SELECT)
                        info->func[0] |=
@@ -281,13 +317,6 @@ static int adm1275_remove(struct i2c_client *client)
        return 0;
 }
 
-static const struct i2c_device_id adm1275_id[] = {
-       { "adm1275", adm1275 },
-       { "adm1276", adm1276 },
-       { }
-};
-MODULE_DEVICE_TABLE(i2c, adm1275_id);
-
 static struct i2c_driver adm1275_driver = {
        .driver = {
                   .name = "adm1275",