lib: utils: identify supported GPIO reset methods

The GPIO reset driver supports reset and poweroff. But not all boards
support both. gpio_system_reset_check() must detect this situation.

Signed-off-by: Heinrich Schuchardt <heinrich.schuchardt@canonical.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>

diff --git a/lib/utils/reset/fdt_reset_gpio.c b/lib/utils/reset/fdt_reset_gpio.c
index 30127f5..77e4d0e 100644 (file)
--- a/lib/utils/reset/fdt_reset_gpio.c
+++ b/lib/utils/reset/fdt_reset_gpio.c
@@ -35,21 +35,9 @@ static struct gpio_reset restart = {
        .inactive_delay = 100
 };
 
-static int gpio_system_reset_check(u32 type, u32 reason)
-{
-       switch (type) {
-       case SBI_SRST_RESET_TYPE_SHUTDOWN:
-       case SBI_SRST_RESET_TYPE_COLD_REBOOT:
-       case SBI_SRST_RESET_TYPE_WARM_REBOOT:
-               return 1;
-       }
-
-       return 0;
-}
-
-static void gpio_system_reset(u32 type, u32 reason)
+static struct gpio_reset *gpio_get_reset_settings(u32 type)
 {
-       struct gpio_reset *reset = NULL;
+       struct gpio_reset *reset;
 
        switch (type) {
        case SBI_SRST_RESET_TYPE_SHUTDOWN:
@@ -59,14 +47,26 @@ static void gpio_system_reset(u32 type, u32 reason)
        case SBI_SRST_RESET_TYPE_WARM_REBOOT:
                reset = &restart;
                break;
+       default:
+               reset = NULL;
        }
 
-       if (reset) {
-               if (!reset->pin.chip) {
-                       sbi_printf("%s: gpio pin not available\n", __func__);
-                       goto skip_reset;
-               }
+       if (reset && !reset->pin.chip)
+               reset = NULL;
+
+       return reset;
+}
+
+static int gpio_system_reset_check(u32 type, u32 reason)
+{
+       return !!gpio_get_reset_settings(type);
+}
+
+static void gpio_system_reset(u32 type, u32 reason)
+{
+       struct gpio_reset *reset = gpio_get_reset_settings(type);
 
+       if (reset) {
                /* drive it active, also inactive->active edge */
                gpio_direction_output(&reset->pin, 1);
                sbi_timer_mdelay(reset->active_delay);
@@ -77,11 +77,9 @@ static void gpio_system_reset(u32 type, u32 reason)
 
                /* drive it active, also inactive->active edge */
                gpio_set(&reset->pin, 1);
-
-skip_reset:
-               /* hang !!! */
-               sbi_hart_hang();
        }
+       /* hang !!! */
+       sbi_hart_hang();
 }
 
 static struct sbi_system_reset_device gpio_reset = {