gpio: Clarify that <linux/gpio.h> is legacy

It should be clear to developers that they should not include
this file in new code.

Suggested-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

diff --git a/include/linux/gpio.h b/include/linux/gpio.h
index 8ef7fc0ce0f0cb408bf04a9a01cea0eb2309815b..91ed23468530d3a7df959fc2e99a501e78c231f1 100644 (file)
--- a/include/linux/gpio.h
+++ b/include/linux/gpio.h
@@ -1,4 +1,14 @@
 /* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * <linux/gpio.h>
+ *
+ * This is the LEGACY GPIO bulk include file, including legacy APIs. It is
+ * used for GPIO drivers still referencing the global GPIO numberspace,
+ * and should not be included in new code.
+ *
+ * If you're implementing a GPIO driver, only include <linux/gpio/driver.h>
+ * If you're implementing a GPIO consumer, only include <linux/gpio/consumer.h>
+ */
 #ifndef __LINUX_GPIO_H
 #define __LINUX_GPIO_H