allwinner: Introduce GPIO helper function
Many boards without a dedicated PMIC contain simple regulators, which
can be controlled via GPIO pins.
To later allow turning them off easily, introduce a simple function to
configure a given pin as a GPIO out pin and set it to the desired level.
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
diff --git a/plat/allwinner/common/sunxi_common.c b/plat/allwinner/common/sunxi_common.c
index ea77afb..88156b5 100644
--- a/plat/allwinner/common/sunxi_common.c
+++ b/plat/allwinner/common/sunxi_common.c
@@ -71,3 +71,32 @@
return reg >> 16;
}
+
+/*
+ * Configure a given pin to the GPIO-OUT function and sets its level.
+ * The port is given as a capital letter, the pin is the number within
+ * this port group.
+ * So to set pin PC7 to high, use: sunxi_set_gpio_out('C', 7, true);
+ */
+void sunxi_set_gpio_out(char port, int pin, bool level_high)
+{
+ uintptr_t port_base;
+
+ if (port < 'A' || port > 'L')
+ return;
+ if (port == 'L')
+ port_base = SUNXI_R_PIO_BASE;
+ else
+ port_base = SUNXI_PIO_BASE + (port - 'A') * 0x24;
+
+ /* Set the new level first before configuring the pin. */
+ if (level_high)
+ mmio_setbits_32(port_base + 0x10, BIT(pin));
+ else
+ mmio_clrbits_32(port_base + 0x10, BIT(pin));
+
+ /* configure pin as GPIO out (4(3) bits per pin, 1: GPIO out */
+ mmio_clrsetbits_32(port_base + (pin / 8) * 4,
+ 0x7 << ((pin % 8) * 4),
+ 0x1 << ((pin % 8) * 4));
+}