From: Sascha Hauer <s.ha...@pengutronix.de>
Signed-off-by: Sascha Hauer <s.ha...@pengutronix.de>
Signed-off-by: Steffen Trumtrar <s.trumt...@pengutronix.de>
---
drivers/Makefile | 1 +
drivers/gpio/Kconfig | 2 +
drivers/gpio/Makefile | 1 +
drivers/gpio/gpio.c | 134 +++++++++++++++++++++++++++++++++++++++++++++++++
include/gpio.h | 27 +++++++++-
5 files changed, 164 insertions(+), 1 deletion(-)
create mode 100644 drivers/gpio/Kconfig
create mode 100644 drivers/gpio/Makefile
create mode 100644 drivers/gpio/gpio.c
diff --git a/drivers/Makefile b/drivers/Makefile
index ea3263f..1d14e6c 100644
--- a/drivers/Makefile
+++ b/drivers/Makefile
@@ -17,3 +17,4 @@ obj-$(CONFIG_PWM) += pwm/
obj-y += input/
obj-y += dma/
obj-y += watchdog/
+obj-y += gpio/
diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig
new file mode 100644
index 0000000..a681973
--- /dev/null
+++ b/drivers/gpio/Kconfig
@@ -0,0 +1,2 @@
+config GPIOLIB
+ bool
diff --git a/drivers/gpio/Makefile b/drivers/gpio/Makefile
new file mode 100644
index 0000000..7837966
--- /dev/null
+++ b/drivers/gpio/Makefile
@@ -0,0 +1 @@
+obj-y += gpio.o
diff --git a/drivers/gpio/gpio.c b/drivers/gpio/gpio.c
new file mode 100644
index 0000000..6ad8d27
--- /dev/null
+++ b/drivers/gpio/gpio.c
@@ -0,0 +1,134 @@
+#include <common.h>
+#include <gpio.h>
+#include <errno.h>
+
+static LIST_HEAD(chip_list);
+
+#define ARCH_NR_GPIOS 256
+
+static struct gpio_chip *gpio_desc[ARCH_NR_GPIOS];
+
+static int gpio_is_valid(unsigned gpio)
+{
+ if (gpio < ARCH_NR_GPIOS)
+ return 1;
+ return 0;
+}
+
+void gpio_set_value(unsigned gpio, int value)
+{
+ struct gpio_chip *chip = gpio_desc[gpio];
+
+ if (!gpio_is_valid(gpio))
+ return;
+ if (!chip)
+ return;
+ if (!chip->ops->set)
+ return;
+ chip->ops->set(chip, gpio - chip->base, value);
+}
+EXPORT_SYMBOL(gpio_set_value);
+
+int gpio_get_value(unsigned gpio)
+{
+ struct gpio_chip *chip = gpio_desc[gpio];
+
+ if (!gpio_is_valid(gpio))
+ return -EINVAL;
+ if (!chip)
+ return -ENODEV;
+ if (!chip->ops->get)
+ return -ENOSYS;
+ return chip->ops->get(chip, gpio - chip->base);
+}
+EXPORT_SYMBOL(gpio_get_value);
+
+int gpio_direction_output(unsigned gpio, int value)
+{
+ struct gpio_chip *chip = gpio_desc[gpio];
+
+ if (!gpio_is_valid(gpio))
+ return -EINVAL;
+ if (!chip)
+ return -ENODEV;
+ if (!chip->ops->direction_output)
+ return -ENOSYS;
+ return chip->ops->direction_output(chip, gpio - chip->base, value);
+}
+EXPORT_SYMBOL(gpio_direction_output);
+
+int gpio_direction_input(unsigned gpio)
+{
+ struct gpio_chip *chip = gpio_desc[gpio];
+
+ if (!gpio_is_valid(gpio))
+ return -EINVAL;
+ if (!chip)
+ return -ENODEV;
+ if (!chip->ops->direction_input)
+ return -ENOSYS;
+ return chip->ops->direction_input(chip, gpio - chip->base);
+}
+EXPORT_SYMBOL(gpio_direction_input);
+
+static int gpiochip_find_base(int start, int ngpio)
+{
+ int i;
+ int spare = 0;
+ int base = -ENOSPC;
+
+ if (start < 0)
+ start = 0;
+
+ for (i = start; i < ARCH_NR_GPIOS; i++) {
+ struct gpio_chip *chip = gpio_desc[i];
+
+ if (!chip) {
+ spare++;
+ if (spare == ngpio) {
+ base = i + 1 - ngpio;
+ break;
+ }
+ } else {
+ spare = 0;
+ i += chip->ngpio - 1;
+ }
+ }
+
+ if (gpio_is_valid(base))
+ debug("%s: found new base at %d\n", __func__, base);
+ return base;
+}
+
+int gpiochip_add(struct gpio_chip *chip)
+{
+ int base, i;
+
+ base = gpiochip_find_base(chip->base, chip->ngpio);
+ if (base < 0)
+ return base;
+
+ if (chip->base >= 0 && chip->base != base)
+ return -EBUSY;
+
+ chip->base = base;
+
+ list_add_tail(&chip->list, &chip_list);
+
+ for (i = chip->base; i < chip->base + chip->ngpio; i++)
+ gpio_desc[i] = chip;
+
+ return 0;
+}
+
+int gpio_get_num(struct device_d *dev, int gpio)
+{
+ struct gpio_chip *chip;
+
+ list_for_each_entry(chip, &chip_list, list) {
+ if (chip->dev == dev)
+ return chip->base + gpio;
+ }
+
+ return -ENODEV;
+}
diff --git a/include/gpio.h b/include/gpio.h
index b7d8402..9fb11c3 100644
--- a/include/gpio.h
+++ b/include/gpio.h
@@ -5,10 +5,35 @@
static inline int gpio_request(unsigned gpio, const char *label)
{
- return 0;
+ return 0;
}
static inline void gpio_free(unsigned gpio)
{
}
+
+struct gpio_chip;
+
+struct gpio_ops {
+ int (*direction_input)(struct gpio_chip *chip, unsigned offset);
+ int (*direction_output)(struct gpio_chip *chip, unsigned offset, int
value);
+ int (*get)(struct gpio_chip *chip, unsigned offset);
+ void (*set)(struct gpio_chip *chip, unsigned offset, int value);
+};
+
+struct gpio_chip {
+ struct device_d *dev;
+
+ int base;
+ int ngpio;
+
+ struct gpio_ops *ops;
+
+ struct list_head list;
+};
+
+int gpiochip_add(struct gpio_chip *chip);
+
+int gpio_get_num(struct device_d *dev, int gpio);
+
#endif /* __GPIO_H */
--
1.7.10.4
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