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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
commit57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch)
tree5e910f0e82173f4ef4f51111366a3f1299037a7b /include/asm-generic/gpio.h
Initial import
Diffstat (limited to 'include/asm-generic/gpio.h')
-rw-r--r--include/asm-generic/gpio.h172
1 files changed, 172 insertions, 0 deletions
diff --git a/include/asm-generic/gpio.h b/include/asm-generic/gpio.h
new file mode 100644
index 000000000..9bb0d1172
--- /dev/null
+++ b/include/asm-generic/gpio.h
@@ -0,0 +1,172 @@
+#ifndef _ASM_GENERIC_GPIO_H
+#define _ASM_GENERIC_GPIO_H
+
+#include <linux/kernel.h>
+#include <linux/types.h>
+#include <linux/errno.h>
+#include <linux/of.h>
+
+#ifdef CONFIG_GPIOLIB
+
+#include <linux/compiler.h>
+#include <linux/gpio/driver.h>
+#include <linux/gpio/consumer.h>
+
+/* 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).
+ *
+ * While the GPIO programming interface defines valid GPIO numbers
+ * to be in the range 0..MAX_INT, this library restricts them to the
+ * smaller range 0..ARCH_NR_GPIOS-1.
+ *
+ * ARCH_NR_GPIOS is somewhat arbitrary; it usually reflects the sum of
+ * builtin/SoC GPIOs plus a number of GPIOs on expanders; the latter is
+ * actually an estimate of a board-specific value.
+ */
+
+#ifndef ARCH_NR_GPIOS
+#define ARCH_NR_GPIOS 512
+#endif
+
+/*
+ * "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)
+{
+ return number >= 0 && number < ARCH_NR_GPIOS;
+}
+
+struct device;
+struct gpio;
+struct seq_file;
+struct module;
+struct device_node;
+struct gpio_desc;
+
+/* caller holds gpio_lock *OR* gpio is marked as requested */
+static inline struct gpio_chip *gpio_to_chip(unsigned gpio)
+{
+ return gpiod_to_chip(gpio_to_desc(gpio));
+}
+
+/* Always use the library code for GPIO management calls,
+ * or when sleeping may be involved.
+ */
+extern int gpio_request(unsigned gpio, const char *label);
+extern 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_set_debounce(unsigned gpio, unsigned debounce)
+{
+ return gpiod_set_debounce(gpio_to_desc(gpio), debounce);
+}
+
+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)
+{
+ return gpiod_set_raw_value_cansleep(gpio_to_desc(gpio), value);
+}
+
+
+/* A platform's <asm/gpio.h> code may want to inline the I/O calls when
+ * the GPIO is constant and refers to some always-present controller,
+ * giving direct access to chip registers and tight bitbanging loops.
+ */
+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)
+{
+ return gpiod_set_raw_value(gpio_to_desc(gpio), value);
+}
+
+static inline int __gpio_cansleep(unsigned gpio)
+{
+ return gpiod_cansleep(gpio_to_desc(gpio));
+}
+
+static inline int __gpio_to_irq(unsigned gpio)
+{
+ return gpiod_to_irq(gpio_to_desc(gpio));
+}
+
+extern int gpio_request_one(unsigned gpio, unsigned long flags, const char *label);
+extern int gpio_request_array(const struct gpio *array, size_t num);
+extern void gpio_free_array(const struct gpio *array, size_t num);
+
+/*
+ * A sysfs interface can be exported by individual drivers if they want,
+ * but more typically is configured entirely from userspace.
+ */
+static inline int gpio_export(unsigned gpio, bool direction_may_change)
+{
+ return gpiod_export(gpio_to_desc(gpio), direction_may_change);
+}
+
+static inline int gpio_export_link(struct device *dev, const char *name,
+ unsigned gpio)
+{
+ return gpiod_export_link(dev, name, gpio_to_desc(gpio));
+}
+
+static inline int gpio_sysfs_set_active_low(unsigned gpio, int value)
+{
+ return gpiod_sysfs_set_active_low(gpio_to_desc(gpio), value);
+}
+
+static inline void gpio_unexport(unsigned gpio)
+{
+ gpiod_unexport(gpio_to_desc(gpio));
+}
+
+#else /* !CONFIG_GPIOLIB */
+
+static inline bool gpio_is_valid(int number)
+{
+ /* only non-negative numbers are valid */
+ return number >= 0;
+}
+
+/* platforms that don't directly support access to GPIOs through I2C, SPI,
+ * or other blocking infrastructure can use these wrappers.
+ */
+
+static inline int gpio_cansleep(unsigned gpio)
+{
+ return 0;
+}
+
+static inline int gpio_get_value_cansleep(unsigned gpio)
+{
+ might_sleep();
+ return __gpio_get_value(gpio);
+}
+
+static inline void gpio_set_value_cansleep(unsigned gpio, int value)
+{
+ might_sleep();
+ __gpio_set_value(gpio, value);
+}
+
+#endif /* !CONFIG_GPIOLIB */
+
+#endif /* _ASM_GENERIC_GPIO_H */