i2c/generic: Add support for GPIO IRQ
Add support for using GPIO IRQ instead of PIRQ with an I2C device.
This allows a device to use an edge triggered interrupt that will
trigger on both high and low transitions.
The _DSD method for describing these GPIOs has a field for 'active
low' which is supposed to be 1 if the pin is active low, otherwise
is zero. The value in here doesn't mean too much for GpioInt() as
those will end up using the value from GpioInt() when it actually
requests the interrupt.
BUG=b:35581264
BRANCH=none
TEST=test on Eve board that codec IRQ can be delcared as GPIO IRQ
Change-Id: I02c64c7fc28dc2d608ad40db889c7242892f16db
Signed-off-by: Duncan Laurie <dlaurie@chromium.org>
Reviewed-on: https://review.coreboot.org/18835
Tested-by: build bot (Jenkins)
Reviewed-by: Aaron Durbin <adurbin@chromium.org>
Reviewed-by: Furquan Shaikh <furquan@google.com>
diff --git a/src/drivers/i2c/generic/chip.h b/src/drivers/i2c/generic/chip.h
index a4f85df..5810db8 100644
--- a/src/drivers/i2c/generic/chip.h
+++ b/src/drivers/i2c/generic/chip.h
@@ -29,6 +29,9 @@
unsigned wake; /* Wake GPE */
struct acpi_irq irq; /* Interrupt */
+ /* Use GPIO based interrupt instead of PIRQ */
+ struct acpi_gpio irq_gpio;
+
/*
* This flag will add a device propery which will indicate
* to the OS that it should probe this device before adding it.
diff --git a/src/drivers/i2c/generic/generic.c b/src/drivers/i2c/generic/generic.c
index dea78d5..f8de1c2 100644
--- a/src/drivers/i2c/generic/generic.c
+++ b/src/drivers/i2c/generic/generic.c
@@ -68,7 +68,7 @@
};
struct acpi_dp *dsd = NULL;
int curr_index = 0;
- int reset_gpio_index = -1, enable_gpio_index = -1;
+ int reset_gpio_index = -1, enable_gpio_index = -1, irq_gpio_index = -1;
const char *path = acpi_device_path(dev);
if (!dev->enabled || !scope)
@@ -93,7 +93,14 @@
acpigen_write_name("_CRS");
acpigen_write_resourcetemplate_header();
acpi_device_write_i2c(&i2c);
- acpi_device_write_interrupt(&config->irq);
+
+ /* Use either Interrupt() or GpioInt() */
+ if (config->irq_gpio.pin_count)
+ irq_gpio_index = i2c_generic_write_gpio(&config->irq_gpio,
+ &curr_index);
+ else
+ acpi_device_write_interrupt(&config->irq);
+
if (i2c_generic_add_gpios_to_crs(config) == true) {
reset_gpio_index = i2c_generic_write_gpio(&config->reset_gpio,
&curr_index);
@@ -110,10 +117,15 @@
/* DSD */
if (config->probed || (reset_gpio_index != -1) ||
- (enable_gpio_index != -1)) {
+ (enable_gpio_index != -1) || (irq_gpio_index != -1)) {
dsd = acpi_dp_new_table("_DSD");
if (config->probed)
acpi_dp_add_integer(dsd, "linux,probed", 1);
+ if (irq_gpio_index != -1)
+ acpi_dp_add_gpio(dsd, "irq-gpios", path,
+ irq_gpio_index, 0,
+ config->irq_gpio.polarity ==
+ ACPI_GPIO_ACTIVE_LOW);
if (reset_gpio_index != -1)
acpi_dp_add_gpio(dsd, "reset-gpios", path,
reset_gpio_index, 0,