nvmem: core: Allow specifying device name verbatim

Add code to allow avoid having nvmem core append a numeric suffix to
the end of the name by passing config->id of -1.

Cc: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Cc: Heiko Stuebner <heiko@sntech.de>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Carlo Caione <carlo@caione.org>
Cc: Kevin Hilman <khilman@baylibre.com>
Cc: Matthias Brugger <matthias.bgg@gmail.com>
Cc: cphealy@gmail.com
Cc: linux-kernel@vger.kernel.org
Cc: linux-mediatek@lists.infradead.org
Cc: linux-rockchip@lists.infradead.org
Cc: linux-amlogic@lists.infradead.org
Cc: linux-arm-kernel@lists.infradead.org
Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/nvmem/core.c

@@ -473,9 +473,14 @@ struct nvmem_device *nvmem_register(const struct nvmem_config *config)
 	nvmem->reg_read = config->reg_read;
 	nvmem->reg_write = config->reg_write;
 	nvmem->dev.of_node = config->dev->of_node;
-	dev_set_name(&nvmem->dev, "%s%d",
-		     config->name ? : "nvmem",
-		     config->name ? config->id : nvmem->id);
+
+	if (config->id == -1 && config->name) {
+		dev_set_name(&nvmem->dev, "%s", config->name);
+	} else {
+		dev_set_name(&nvmem->dev, "%s%d",
+			     config->name ? : "nvmem",
+			     config->name ? config->id : nvmem->id);
+	}
 
 	nvmem->read_only = device_property_present(config->dev, "read-only") |
 			   config->read_only;

include/linux/nvmem-provider.h

@@ -43,6 +43,9 @@ typedef int (*nvmem_reg_write_t)(void *priv, unsigned int offset,
  * Note: A default "nvmem<id>" name will be assigned to the device if
  * no name is specified in its configuration. In such case "<id>" is
  * generated with ida_simple_get() and provided id field is ignored.
+ *
+ * Note: Specifying name and setting id to -1 implies a unique device
+ * whose name is provided as-is (kept unaltered).
  */
 struct nvmem_config {
 	struct device		*dev;