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, 12 insertions, 7 deletions

diff --git a/drivers/hwmon/pmbus/ibm-cffps.c b/drivers/hwmon/pmbus/ibm-cffps.c
index 7d300f2f338d..2fb7540ee952 100644
--- a/drivers/hwmon/pmbus/ibm-cffps.c
+++ b/drivers/hwmon/pmbus/ibm-cffps.c
@@ -91,6 +91,8 @@ struct ibm_cffps {
 	struct led_classdev led;
 };
 
+static const struct i2c_device_id ibm_cffps_id[];
+
 #define to_psu(x, y) container_of((x), struct ibm_cffps, debugfs_entries[(y)])
 
 static ssize_t ibm_cffps_read_input_history(struct ibm_cffps *psu,
@@ -473,8 +475,7 @@ static struct pmbus_platform_data ibm_cffps_pdata = {
 	.flags = PMBUS_SKIP_STATUS_CHECK,
 };
 
-static int ibm_cffps_probe(struct i2c_client *client,
-			   const struct i2c_device_id *id)
+static int ibm_cffps_probe(struct i2c_client *client)
 {
 	int i, rc;
 	enum versions vs = cffps_unknown;
@@ -482,11 +483,15 @@ static int ibm_cffps_probe(struct i2c_client *client,
 	struct dentry *ibm_cffps_dir;
 	struct ibm_cffps *psu;
 	const void *md = of_device_get_match_data(&client->dev);
+	const struct i2c_device_id *id;
 
-	if (md)
+	if (md) {
 		vs = (enum versions)md;
-	else if (id)
-		vs = (enum versions)id->driver_data;
+	} else {
+		id = i2c_match_id(ibm_cffps_id, client);
+		if (id)
+			vs = (enum versions)id->driver_data;
+	}
 
 	if (vs == cffps_unknown) {
 		u16 ccin_revision = 0;
@@ -519,7 +524,7 @@ static int ibm_cffps_probe(struct i2c_client *client,
 	}
 
 	client->dev.platform_data = &ibm_cffps_pdata;
-	rc = pmbus_do_probe(client, id, &ibm_cffps_info[vs]);
+	rc = pmbus_do_probe(client, &ibm_cffps_info[vs]);
 	if (rc)
 		return rc;
 
@@ -611,7 +616,7 @@ static struct i2c_driver ibm_cffps_driver = {
 		.name = "ibm-cffps",
 		.of_match_table = ibm_cffps_of_match,
 	},
-	.probe = ibm_cffps_probe,
+	.probe_new = ibm_cffps_probe,
 	.remove = pmbus_do_remove,
 	.id_table = ibm_cffps_id,
 };