i2c: replace i2c_new_secondary_device with an ERR_PTR variant

In the general move to have i2c_new_*_device functions which return
ERR_PTR instead of NULL, this patch converts i2c_new_secondary_device().

There are only few users, so this patch converts the I2C core and all
users in one go. The function gets renamed to i2c_new_ancillary_device()
so out-of-tree users will get a build failure to understand they need to
adapt their error checking code.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Kieran Bingham <kieran.bingham+renesas@ideasonboard.com> # adv748x
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> # adv7511 + adv7604
Reviewed-by: Hans Verkuil <hverkuil-cisco@xs4all.nl> # adv7604
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

drivers/media/i2c/adv748x/adv748x-core.c

@@ -183,14 +183,14 @@ static int adv748x_initialise_clients(struct adv748x_state *state)
 	int ret;
 
 	for (i = ADV748X_PAGE_DPLL; i < ADV748X_PAGE_MAX; ++i) {
-		state->i2c_clients[i] = i2c_new_secondary_device(
+		state->i2c_clients[i] = i2c_new_ancillary_device(
 				state->client,
 				adv748x_default_addresses[i].name,
 				adv748x_default_addresses[i].default_addr);
 
-		if (state->i2c_clients[i] == NULL) {
+		if (IS_ERR(state->i2c_clients[i])) {
 			adv_err(state, "failed to create i2c client %u\n", i);
-			return -ENOMEM;
+			return PTR_ERR(state->i2c_clients[i]);
 		}
 
 		ret = adv748x_configure_regmap(state, i);

drivers/media/i2c/adv7604.c

@@ -2862,10 +2862,8 @@ static void adv76xx_unregister_clients(struct adv76xx_state *state)
 {
 	unsigned int i;
 
-	for (i = 1; i < ARRAY_SIZE(state->i2c_clients); ++i) {
-		if (state->i2c_clients[i])
-			i2c_unregister_device(state->i2c_clients[i]);
-	}
+	for (i = 1; i < ARRAY_SIZE(state->i2c_clients); ++i)
+		i2c_unregister_device(state->i2c_clients[i]);
 }
 
 static struct i2c_client *adv76xx_dummy_client(struct v4l2_subdev *sd,
@@ -2878,14 +2876,14 @@ static struct i2c_client *adv76xx_dummy_client(struct v4l2_subdev *sd,
 	struct i2c_client *new_client;
 
 	if (pdata && pdata->i2c_addresses[page])
-		new_client = i2c_new_dummy(client->adapter,
+		new_client = i2c_new_dummy_device(client->adapter,
 					   pdata->i2c_addresses[page]);
 	else
-		new_client = i2c_new_secondary_device(client,
+		new_client = i2c_new_ancillary_device(client,
 				adv76xx_default_addresses[page].name,
 				adv76xx_default_addresses[page].default_addr);
 
-	if (new_client)
+	if (!IS_ERR(new_client))
 		io_write(sd, io_reg, new_client->addr << 1);
 
 	return new_client;
@@ -3516,15 +3514,19 @@ static int adv76xx_probe(struct i2c_client *client,
 	}
 
 	for (i = 1; i < ADV76XX_PAGE_MAX; ++i) {
+		struct i2c_client *dummy_client;
+
 		if (!(BIT(i) & state->info->page_mask))
 			continue;
 
-		state->i2c_clients[i] = adv76xx_dummy_client(sd, i);
-		if (!state->i2c_clients[i]) {
-			err = -EINVAL;
+		dummy_client = adv76xx_dummy_client(sd, i);
+		if (IS_ERR(dummy_client)) {
+			err = PTR_ERR(dummy_client);
 			v4l2_err(sd, "failed to create i2c client %u\n", i);
 			goto err_i2c;
 		}
+
+		state->i2c_clients[i] = dummy_client;
 	}
 
 	INIT_DELAYED_WORK(&state->delayed_work_enable_hotplug,