arch/x86/acpigen: Provide helper functions for enabling/disabling GPIO

In order to allow GPIOs to be set/clear according to their polarity,
provide helper functions that check for polarity and call set/clear
SoC functions for generating ACPI code.

BUG=None
BRANCH=None
TEST=Verified that the ACPI code generated remains the same as before
for reef.

Change-Id: Ie8bdb9dc18e61a4a658f1447d6f1db0b166d9c12
Signed-off-by: Furquan Shaikh <furquan@chromium.org>
Reviewed-on: https://review.coreboot.org/18427
Reviewed-by: Aaron Durbin <adurbin@chromium.org>
Tested-by: build bot (Jenkins)

3 files changed, 39 insertions, 5 deletions

diff --git a/src/arch/x86/acpi_device.c b/src/arch/x86/acpi_device.c
index 323d4f1eab..42305a6ab4 100644
--- a/src/arch/x86/acpi_device.c
+++ b/src/arch/x86/acpi_device.c
@@ -512,14 +512,14 @@ void acpi_device_add_power_res(
 	/* Method (_ON, 0, Serialized) */
 	acpigen_write_method_serialized("_ON", 0);
 	if (reset_gpio)
-		acpigen_soc_set_tx_gpio(reset_gpio);
+		acpigen_enable_tx_gpio(reset);
 	if (enable_gpio) {
-		acpigen_soc_set_tx_gpio(enable_gpio);
+		acpigen_enable_tx_gpio(enable);
 		if (enable_delay_ms)
 			acpigen_write_sleep(enable_delay_ms);
 	}
 	if (reset_gpio) {
-		acpigen_soc_clear_tx_gpio(reset_gpio);
+		acpigen_disable_tx_gpio(reset);
 		if (reset_delay_ms)
 			acpigen_write_sleep(reset_delay_ms);
 	}
@@ -528,9 +528,9 @@ void acpi_device_add_power_res(
 	/* Method (_OFF, 0, Serialized) */
 	acpigen_write_method_serialized("_OFF", 0);
 	if (reset_gpio)
-		acpigen_soc_set_tx_gpio(reset_gpio);
+		acpigen_enable_tx_gpio(reset);
 	if (enable_gpio)
-		acpigen_soc_clear_tx_gpio(enable_gpio);
+		acpigen_disable_tx_gpio(enable);
 	acpigen_pop_len();		/* _OFF method */
 
 	acpigen_pop_len();		/* PowerResource PRIC */
diff --git a/src/arch/x86/acpigen.c b/src/arch/x86/acpigen.c
index 8ebdd0982c..d3ec05fe3d 100644
--- a/src/arch/x86/acpigen.c
+++ b/src/arch/x86/acpigen.c
@@ -1299,3 +1299,26 @@ int __attribute__((weak)) acpigen_soc_clear_tx_gpio(unsigned int gpio_num)
 	acpigen_write_debug_string("clear_tx_gpio not available");
 	return -1;
 }
+
+/*
+ * Helper functions for enabling/disabling Tx GPIOs based on the GPIO
+ * polarity. These functions end up calling acpigen_soc_{set,clear}_tx_gpio to
+ * make callbacks into SoC acpigen code.
+ *
+ * Returns 0 on success and -1 on error.
+ */
+int acpigen_enable_tx_gpio(struct acpi_gpio *gpio)
+{
+	if (gpio->polarity == ACPI_GPIO_ACTIVE_HIGH)
+		return acpigen_soc_set_tx_gpio(gpio->pins[0]);
+	else
+		return acpigen_soc_clear_tx_gpio(gpio->pins[0]);
+}
+
+int acpigen_disable_tx_gpio(struct acpi_gpio *gpio)
+{
+	if (gpio->polarity == ACPI_GPIO_ACTIVE_LOW)
+		return acpigen_soc_set_tx_gpio(gpio->pins[0]);
+	else
+		return acpigen_soc_clear_tx_gpio(gpio->pins[0]);
+}
diff --git a/src/arch/x86/include/arch/acpigen.h b/src/arch/x86/include/arch/acpigen.h
index f76d85e9bc..c1c4d598c4 100644
--- a/src/arch/x86/include/arch/acpigen.h
+++ b/src/arch/x86/include/arch/acpigen.h
@@ -21,6 +21,7 @@
 #include <stdlib.h>
 #include <stdint.h>
 #include <arch/acpi.h>
+#include <arch/acpi_device.h>
 
 /* Values that can be returned for ACPI Device _STA method */
 #define ACPI_STATUS_DEVICE_PRESENT	(1 << 0)
@@ -289,4 +290,14 @@ int acpigen_soc_set_tx_gpio(unsigned int gpio_num);
 /* Generate ACPI AML code to set Tx value of GPIO to 0. */
 int acpigen_soc_clear_tx_gpio(unsigned int gpio_num);
 
+/*
+ * Helper functions for enabling/disabling Tx GPIOs based on the GPIO
+ * polarity. These functions end up calling acpigen_soc_{set,clear}_tx_gpio to
+ * make callbacks into SoC acpigen code.
+ *
+ * Returns 0 on success and -1 on error.
+ */
+int acpigen_enable_tx_gpio(struct acpi_gpio *gpio);
+int acpigen_disable_tx_gpio(struct acpi_gpio *gpio);
+
 #endif