gpio: enhance exception handling in interface function

 - GPIO set type functions require prerequisites

 1) [edge_mode]                [direction]

    none ----------------------> in, out (O)

    rising, falling, both -----> in (O)
                           \
                            ---> out (X)

 2) [direction]                [edge_mode]

    in ------------------------> none, rising, falling, both (O)

    out -----------------------> none (O)
              \
               ----------------> rising, falling, both (X)

 3) [direction]                [value]

    in ------------------------> read (O)
              \
               ----------------> write (X)

    out -----------------------> read, write (O)

Change-Id: I72f8557568916b01c1e2e9edef79ed79f5bb20e6
Signed-off-by: Segwon <segwon.han@samsung.com>

diff --git a/src/interface/peripheral_interface_gpio.c b/src/interface/peripheral_interface_gpio.c
index 4ca79e4..119230d 100644 (file)
--- a/src/interface/peripheral_interface_gpio.c
+++ b/src/interface/peripheral_interface_gpio.c
@@ -40,8 +40,20 @@ int peripheral_interface_gpio_set_initial_direction_into_handle(peripheral_gpio_
        return PERIPHERAL_ERROR_IO_ERROR;
 }
 
+/*
+ *      [edge_mode]                [direction]
+ *
+ *          none -----------------> in, out (O)
+ *
+ * rising, falling, both ---------> in (O)
+ *                          \
+ *                           -----> out (X)
+ */
 int peripheral_interface_gpio_set_direction(peripheral_gpio_h gpio, peripheral_gpio_direction_e direction)
 {
+       RETV_IF(gpio->direction == direction, PERIPHERAL_ERROR_NONE);
+       RETV_IF(gpio->edge != PERIPHERAL_GPIO_EDGE_NONE, PERIPHERAL_ERROR_IO_ERROR);
+
        static predefined_type_s types[3] = {
                {"in",   2},
                {"high", 4},
@@ -81,8 +93,20 @@ int peripheral_interface_gpio_set_initial_edge_into_handle(peripheral_gpio_h gpi
        return PERIPHERAL_ERROR_IO_ERROR;
 }
 
+/*
+ * [direction]          [edge_mode]
+ *
+ *    in ---------> none, rising, falling, both (O)
+ *
+ *    out --------> none (O)
+ *          \
+ *           -----> rising, falling, both (X)
+ */
 int peripheral_interface_gpio_set_edge_mode(peripheral_gpio_h gpio, peripheral_gpio_edge_e edge)
 {
+       RETV_IF(gpio->edge == edge, PERIPHERAL_ERROR_NONE);
+       RETV_IF(gpio->direction != PERIPHERAL_GPIO_DIRECTION_IN, PERIPHERAL_ERROR_IO_ERROR);
+
        static predefined_type_s types[4] = {
                {"none",    4},
                {"rising",  6},
@@ -98,8 +122,16 @@ int peripheral_interface_gpio_set_edge_mode(peripheral_gpio_h gpio, peripheral_g
        return PERIPHERAL_ERROR_NONE;
 }
 
+/*
+ * [direction]     [value]
+ *
+ *    in ---------> write (X)
+ *    out --------> write (O)
+ */
 int peripheral_interface_gpio_write(peripheral_gpio_h gpio, uint32_t value)
 {
+       RETV_IF(gpio->direction == PERIPHERAL_GPIO_DIRECTION_IN, PERIPHERAL_ERROR_IO_ERROR);
+
        static predefined_type_s types[2] = {
                {"0", 1},
                {"1", 1}
@@ -111,6 +143,12 @@ int peripheral_interface_gpio_write(peripheral_gpio_h gpio, uint32_t value)
        return PERIPHERAL_ERROR_NONE;
 }
 
+/*
+ * [direction]     [value]
+ *
+ *    in ---------> read (O)
+ *    out --------> read (O)
+ */
 int peripheral_interface_gpio_read(peripheral_gpio_h gpio, uint32_t *value)
 {
        int ret;
@@ -151,4 +189,4 @@ int peripheral_interface_gpio_close_isr(peripheral_gpio_h gpio)
        // TODO: unset interrupted callback function
 
        return PERIPHERAL_ERROR_NONE;
-}
\ No newline at end of file
+}