gpiolib: move legacy interface into linux/gpio/legacy.h

Split the old contents from gpio.h for clarity. Ideally any driver
that still includes linux/gpio.h can now be ported over to use
either linux/gpio/legacy.h or linux/gpio/consumer.h, with the
original file getting removed once that is complete.

No functional changes intended for now.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Link: https://patch.msgid.link/20260428154522.2861492-1-arnd@kernel.org
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com>

1 files changed, 173 insertions, 0 deletions

diff --git a/include/linux/gpio/legacy.h b/include/linux/gpio/legacy.h
new file mode 100644
index 000000000000..557ef635935e
--- /dev/null
+++ b/include/linux/gpio/legacy.h
@@ -0,0 +1,173 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * This is the LEGACY GPIO include file, used only for legacy APIs.
+ *
+ * No new code should use this, but instead use the linux/gpio/consumer.h
+ * interfaces directly.
+ */
+
+#ifndef __LINUX_GPIO_LEGACY_H
+#define __LINUX_GPIO_LEGACY_H
+
+#include <linux/types.h>
+
+#ifdef CONFIG_GPIOLIB_LEGACY
+
+struct device;
+
+/* make these flag values available regardless of GPIO kconfig options */
+#define GPIOF_IN		((1 << 0))
+#define GPIOF_OUT_INIT_LOW	((0 << 0) | (0 << 1))
+#define GPIOF_OUT_INIT_HIGH	((0 << 0) | (1 << 1))
+
+#ifdef CONFIG_GPIOLIB
+
+#include <linux/gpio/consumer.h>
+
+/*
+ * "valid" GPIO numbers are nonnegative and may be passed to
+ * setup routines like gpio_request().  Only some valid numbers
+ * can successfully be requested and used.
+ *
+ * Invalid GPIO numbers are useful for indicating no-such-GPIO in
+ * platform data and other tables.
+ */
+static inline bool gpio_is_valid(int number)
+{
+	/* only non-negative numbers are valid */
+	return number >= 0;
+}
+
+/*
+ * Platforms may implement their GPIO interface with library code,
+ * at a small performance cost for non-inlined operations and some
+ * extra memory (for code and for per-GPIO table entries).
+ */
+
+/* Always use the library code for GPIO management calls,
+ * or when sleeping may be involved.
+ */
+int gpio_request(unsigned gpio, const char *label);
+void gpio_free(unsigned gpio);
+
+static inline int gpio_direction_input(unsigned gpio)
+{
+	return gpiod_direction_input(gpio_to_desc(gpio));
+}
+static inline int gpio_direction_output(unsigned gpio, int value)
+{
+	return gpiod_direction_output_raw(gpio_to_desc(gpio), value);
+}
+
+static inline int gpio_get_value_cansleep(unsigned gpio)
+{
+	return gpiod_get_raw_value_cansleep(gpio_to_desc(gpio));
+}
+static inline void gpio_set_value_cansleep(unsigned gpio, int value)
+{
+	gpiod_set_raw_value_cansleep(gpio_to_desc(gpio), value);
+}
+
+static inline int gpio_get_value(unsigned gpio)
+{
+	return gpiod_get_raw_value(gpio_to_desc(gpio));
+}
+static inline void gpio_set_value(unsigned gpio, int value)
+{
+	gpiod_set_raw_value(gpio_to_desc(gpio), value);
+}
+
+static inline int gpio_to_irq(unsigned gpio)
+{
+	return gpiod_to_irq(gpio_to_desc(gpio));
+}
+
+int gpio_request_one(unsigned gpio, unsigned long flags, const char *label);
+
+int devm_gpio_request_one(struct device *dev, unsigned gpio,
+			  unsigned long flags, const char *label);
+
+#else /* ! CONFIG_GPIOLIB */
+
+#include <linux/kernel.h>
+
+#include <asm/bug.h>
+#include <asm/errno.h>
+
+static inline bool gpio_is_valid(int number)
+{
+	return false;
+}
+
+static inline int gpio_request(unsigned gpio, const char *label)
+{
+	return -ENOSYS;
+}
+
+static inline int gpio_request_one(unsigned gpio,
+					unsigned long flags, const char *label)
+{
+	return -ENOSYS;
+}
+
+static inline void gpio_free(unsigned gpio)
+{
+	might_sleep();
+
+	/* GPIO can never have been requested */
+	WARN_ON(1);
+}
+
+static inline int gpio_direction_input(unsigned gpio)
+{
+	return -ENOSYS;
+}
+
+static inline int gpio_direction_output(unsigned gpio, int value)
+{
+	return -ENOSYS;
+}
+
+static inline int gpio_get_value(unsigned gpio)
+{
+	/* GPIO can never have been requested or set as {in,out}put */
+	WARN_ON(1);
+	return 0;
+}
+
+static inline void gpio_set_value(unsigned gpio, int value)
+{
+	/* GPIO can never have been requested or set as output */
+	WARN_ON(1);
+}
+
+static inline int gpio_get_value_cansleep(unsigned gpio)
+{
+	/* GPIO can never have been requested or set as {in,out}put */
+	WARN_ON(1);
+	return 0;
+}
+
+static inline void gpio_set_value_cansleep(unsigned gpio, int value)
+{
+	/* GPIO can never have been requested or set as output */
+	WARN_ON(1);
+}
+
+static inline int gpio_to_irq(unsigned gpio)
+{
+	/* GPIO can never have been requested or set as input */
+	WARN_ON(1);
+	return -EINVAL;
+}
+
+static inline int devm_gpio_request_one(struct device *dev, unsigned gpio,
+					unsigned long flags, const char *label)
+{
+	WARN_ON(1);
+	return -EINVAL;
+}
+
+#endif /* ! CONFIG_GPIOLIB */
+#endif /* CONFIG_GPIOLIB_LEGACY */
+#endif /* __LINUX_GPIO_LEGAGY_H */