hwmon (pmbus) use simple i2c probe function

pmbus_do_probe doesn't use the id information provided in its second
argument, so this can be removed, which then allows using the
single-parameter i2c probe function ("probe_new") for probes.

This avoids scanning the identifier tables during probes.

Drivers which didn't use the id are converted as-is; drivers which did
are modified as follows:

* if the information in i2c_client is sufficient, that's used instead
  (client->name);
* configured v. probed comparisons are performed by comparing the
  configured name to the detected name, instead of the ids; this
  involves strcmp but is still cheaper than comparing all the device
  names when scanning the tables;
* anything else is handled by calling i2c_match_id() with the same
  level of error-handling (if any) as before.

Additionally, the mismatch message in the ltc2978 driver is adjusted
so that it no longer assumes that the driver_data is an index into
ltc2978_id.

Signed-off-by: Stephen Kitt <steve@sk2.org>
Acked-by: Wolfram Sang <wsa@kernel.org>
Link: https://lore.kernel.org/r/20200808210004.30880-1-steve@sk2.org
Signed-off-by: Guenter Roeck <linux@roeck-us.net>

1 files changed, 6 insertions, 7 deletions

diff --git a/drivers/hwmon/pmbus/ucd9000.c b/drivers/hwmon/pmbus/ucd9000.c
index 81f4c4f166cd..f8017993e2b4 100644
--- a/drivers/hwmon/pmbus/ucd9000.c
+++ b/drivers/hwmon/pmbus/ucd9000.c
@@ -487,8 +487,7 @@ static int ucd9000_init_debugfs(struct i2c_client *client,
 }
 #endif /* CONFIG_DEBUG_FS */
 
-static int ucd9000_probe(struct i2c_client *client,
-			 const struct i2c_device_id *id)
+static int ucd9000_probe(struct i2c_client *client)
 {
 	u8 block_buffer[I2C_SMBUS_BLOCK_MAX + 1];
 	struct ucd9000_data *data;
@@ -523,12 +522,12 @@ static int ucd9000_probe(struct i2c_client *client,
 	if (client->dev.of_node)
 		chip = (enum chips)of_device_get_match_data(&client->dev);
 	else
-		chip = id->driver_data;
+		chip = mid->driver_data;
 
-	if (chip != ucd9000 && chip != mid->driver_data)
+	if (chip != ucd9000 && strcmp(client->name, mid->name) != 0)
 		dev_notice(&client->dev,
 			   "Device mismatch: Configured %s, detected %s\n",
-			   id->name, mid->name);
+			   client->name, mid->name);
 
 	data = devm_kzalloc(&client->dev, sizeof(struct ucd9000_data),
 			    GFP_KERNEL);
@@ -603,7 +602,7 @@ static int ucd9000_probe(struct i2c_client *client,
 
 	ucd9000_probe_gpio(client, mid, data);
 
-	ret = pmbus_do_probe(client, mid, info);
+	ret = pmbus_do_probe(client, info);
 	if (ret)
 		return ret;
 
@@ -621,7 +620,7 @@ static struct i2c_driver ucd9000_driver = {
 		.name = "ucd9000",
 		.of_match_table = of_match_ptr(ucd9000_of_match),
 	},
-	.probe = ucd9000_probe,
+	.probe_new = ucd9000_probe,
 	.remove = pmbus_do_remove,
 	.id_table = ucd9000_id,
 };