gpio: add pull up/down flags

Signed-off-by: Nascs <[email protected]>
Co-authored-by: ZHANG Yuntian <[email protected]>

Author: nascs

api/mraa/gpio.h

@@ -67,6 +67,7 @@ typedef enum {
     MRAA_GPIOD_ACTIVE_LOW = 4,
     MRAA_GPIOD_OPEN_DRAIN = 5,
     MRAA_GPIOD_OPEN_SOURCE = 6,
+    MRAA_GPIOD_BIAS_DISABLE = 7,
 } mraa_gpio_mode_t;
 
 /**

include/gpio/gpio_chardev.h

@@ -46,6 +46,9 @@ mraa_boolean_t mraa_is_gpio_line_dir_out(mraa_gpiod_line_info *linfo);
 mraa_boolean_t mraa_is_gpio_line_active_low(mraa_gpiod_line_info *linfo);
 mraa_boolean_t mraa_is_gpio_line_open_drain(mraa_gpiod_line_info *linfo);
 mraa_boolean_t mraa_is_gpio_line_open_source(mraa_gpiod_line_info *linfo);
+mraa_boolean_t mraa_is_gpio_line_bias_pull_up(mraa_gpiod_line_info *linfo);
+mraa_boolean_t mraa_is_gpio_line_bias_pull_down(mraa_gpiod_line_info *linfo);
+mraa_boolean_t mraa_is_gpio_line_bias_disable(mraa_gpiod_line_info *linfo);
 
 int mraa_get_number_of_gpio_chips();
 int mraa_get_chip_infos(mraa_gpiod_chip_info*** cinfos);

include/linux/gpio.h

@@ -21,6 +21,9 @@ struct gpiochip_info {
 #define GPIOLINE_FLAG_ACTIVE_LOW        (1UL << 2)
 #define GPIOLINE_FLAG_OPEN_DRAIN        (1UL << 3)
 #define GPIOLINE_FLAG_OPEN_SOURCE       (1UL << 4)
+#define GPIOLINE_FLAG_BIAS_PULL_UP      (1UL << 5)
+#define GPIOLINE_FLAG_BIAS_PULL_DOWN    (1UL << 6)
+#define GPIOLINE_FLAG_BIAS_DISABLE      (1UL << 7)
 
 struct gpioline_info {
     __u32 line_offset;
@@ -36,6 +39,9 @@ struct gpioline_info {
 #define GPIOHANDLE_REQUEST_ACTIVE_LOW   (1UL << 2)
 #define GPIOHANDLE_REQUEST_OPEN_DRAIN   (1UL << 3)
 #define GPIOHANDLE_REQUEST_OPEN_SOURCE  (1UL << 4)
+#define GPIOHANDLE_REQUEST_BIAS_PULL_UP (1UL << 5)
+#define GPIOHANDLE_REQUEST_BIAS_PULL_DOWN (1UL << 6)
+#define GPIOHANDLE_REQUEST_BIAS_DISABLE	(1UL << 7)
 
 struct gpiohandle_request {
     __u32 lineoffsets[GPIOHANDLES_MAX];

src/gpio/gpio.c

@@ -1110,6 +1110,15 @@ mraa_gpio_mode(mraa_gpio_context dev, mraa_gpio_mode_t mode)
             case MRAA_GPIOD_OPEN_SOURCE:
                 flags |= GPIOHANDLE_REQUEST_OPEN_SOURCE;
                 break;
+            case MRAA_GPIO_PULLUP:
+                flags |= GPIOHANDLE_REQUEST_BIAS_PULL_UP;
+                break;
+            case MRAA_GPIO_PULLDOWN:
+                flags |= GPIOHANDLE_REQUEST_BIAS_PULL_DOWN;
+                break;
+            case MRAA_GPIOD_BIAS_DISABLE:
+                flags |= GPIOHANDLE_REQUEST_BIAS_DISABLE;
+                break;
             default:
                 return MRAA_ERROR_FEATURE_NOT_IMPLEMENTED;
         }

src/gpio/gpio_chardev.c

@@ -429,6 +429,24 @@ mraa_is_gpio_line_open_source(mraa_gpiod_line_info* linfo)
     return (linfo->flags & GPIOLINE_FLAG_OPEN_SOURCE);
 }
 
+mraa_boolean_t
+mraa_is_gpio_line_bias_pull_up(mraa_gpiod_line_info* linfo)
+{
+    return (linfo->flags & GPIOLINE_FLAG_BIAS_PULL_UP);
+}
+
+mraa_boolean_t
+mraa_is_gpio_line_bias_pull_down(mraa_gpiod_line_info* linfo)
+{
+    return (linfo->flags & GPIOLINE_FLAG_BIAS_PULL_DOWN);
+}
+
+mraa_boolean_t
+mraa_is_gpio_line_bias_disable(mraa_gpiod_line_info* linfo)
+{
+    return (linfo->flags & GPIOLINE_FLAG_BIAS_DISABLE);
+}
+
 static int
 dir_filter(const struct dirent* dir)
 {