of: Rename of_modalias_node()

This helper does not produce a real modalias, but tries to get the
"product" compatible part of the "vendor,product" compatibles only. It
is far from creating a purely useful modalias string and does not seem
to be used like that directly anyway, so let's try to give this helper a
more meaningful name before moving there a real modalias helper (already
existing under of/device.c).

Also update the various documentations to refer to the strings as
"aliases" rather than "modaliases" which has a real meaning in the Linux
kernel.

There is no functional change.

Cc: Rafael J. Wysocki <[e-mail]>
Cc: Len Brown <[e-mail]>
Cc: Maarten Lankhorst <[e-mail]>
Cc: Maxime Ripard <[e-mail]>
Cc: Thomas Zimmermann <[e-mail]>
Cc: Sebastian Reichel <[e-mail]>
Cc: Wolfram Sang <[e-mail]>
Cc: Mark Brown <[e-mail]>
Signed-off-by: Miquel Raynal <[e-mail]>
Reviewed-by: Rob Herring <[e-mail]>
Acked-by: Mark Brown <[e-mail]>
Signed-off-by: Srinivas Kandagatla <[e-mail]>
Acked-by: Sebastian Reichel <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Greg Kroah-Hartman <[e-mail]>

drivers/acpi/bus.c

···
  * @modalias:   Pointer to buffer that modalias value will be copied into
  * @len:	Length of modalias buffer
  *
- * This is a counterpart of of_modalias_node() for struct acpi_device objects.
- * If there is a compatible string for @adev, it will be copied to @modalias
- * with the vendor prefix stripped; otherwise, @default_id will be used.
+ * This is a counterpart of of_alias_from_compatible() for struct acpi_device
+ * objects. If there is a compatible string for @adev, it will be copied to
+ * @modalias with the vendor prefix stripped; otherwise, @default_id will be
+ * used.
  */
 void acpi_set_modalias(struct acpi_device *adev, const char *default_id,
 		       char *modalias, size_t len)

drivers/gpu/drm/drm_mipi_dsi.c

···
 	int ret;
 	u32 reg;
 
-	if (of_modalias_node(node, info.type, sizeof(info.type)) < 0) {
+	if (of_alias_from_compatible(node, info.type, sizeof(info.type)) < 0) {
 		drm_err(host, "modalias failure on %pOF\n", node);
 		return ERR_PTR(-EINVAL);
 	}

drivers/hsi/hsi_core.c

···
 	if (!cl)
 		return;
 
-	err = of_modalias_node(client, name, sizeof(name));
+	err = of_alias_from_compatible(client, name, sizeof(name));
 	if (err)
 		goto err;
 

drivers/i2c/busses/i2c-powermac.c

···
 	 */
 
 	/* First try proper modalias */
-	if (of_modalias_node(node, tmp, sizeof(tmp)) >= 0) {
+	if (of_alias_from_compatible(node, tmp, sizeof(tmp)) >= 0) {
 		snprintf(type, type_size, "MAC,%s", tmp);
 		return true;
 	}

drivers/i2c/i2c-core-of.c

···
 
 	memset(info, 0, sizeof(*info));
 
-	if (of_modalias_node(node, info->type, sizeof(info->type)) < 0) {
+	if (of_alias_from_compatible(node, info->type, sizeof(info->type)) < 0) {
 		dev_err(dev, "of_i2c: modalias failure on %pOF\n", node);
 		return -EINVAL;
 	}

drivers/of/base.c

···
 EXPORT_SYMBOL(of_find_matching_node_and_match);
 
 /**
- * of_modalias_node - Lookup appropriate modalias for a device node
+ * of_alias_from_compatible - Lookup appropriate alias for a device node
+ *			      depending on compatible
  * @node:	pointer to a device tree node
- * @modalias:	Pointer to buffer that modalias value will be copied into
- * @len:	Length of modalias value
+ * @alias:	Pointer to buffer that alias value will be copied into
+ * @len:	Length of alias value
  *
  * Based on the value of the compatible property, this routine will attempt
- * to choose an appropriate modalias value for a particular device tree node.
+ * to choose an appropriate alias value for a particular device tree node.
  * It does this by stripping the manufacturer prefix (as delimited by a ',')
  * from the first entry in the compatible list property.
  *
+ * Note: The matching on just the "product" side of the compatible is a relic
+ * from I2C and SPI. Please do not add any new user.
+ *
  * Return: This routine returns 0 on success, <0 on failure.
  */
-int of_modalias_node(struct device_node *node, char *modalias, int len)
+int of_alias_from_compatible(const struct device_node *node, char *alias, int len)
 {
 	const char *compatible, *p;
 	int cplen;
···
 	if (!compatible || strlen(compatible) > cplen)
 		return -ENODEV;
 	p = strchr(compatible, ',');
-	strscpy(modalias, p ? p + 1 : compatible, len);
+	strscpy(alias, p ? p + 1 : compatible, len);
 	return 0;
 }
-EXPORT_SYMBOL_GPL(of_modalias_node);
+EXPORT_SYMBOL_GPL(of_alias_from_compatible);
 
 /**
  * of_find_node_by_phandle - Find a node given a phandle

drivers/spi/spi.c

···
 	}
 
 	/* Select device driver */
-	rc = of_modalias_node(nc, spi->modalias,
-				sizeof(spi->modalias));
+	rc = of_alias_from_compatible(nc, spi->modalias,
+				      sizeof(spi->modalias));
 	if (rc < 0) {
 		dev_err(&ctlr->dev, "cannot find modalias for %pOF\n", nc);
 		goto err_out;

include/linux/of.h

···
 extern int of_n_size_cells(struct device_node *np);
 extern const struct of_device_id *of_match_node(
 	const struct of_device_id *matches, const struct device_node *node);
-extern int of_modalias_node(struct device_node *node, char *modalias, int len);
+extern int of_alias_from_compatible(const struct device_node *node, char *alias,
+				    int len);
 extern void of_print_phandle_args(const char *msg, const struct of_phandle_args *args);
 extern int __of_parse_phandle_with_args(const struct device_node *np,
 	const char *list_name, const char *cells_name, int cell_count,