[coreboot-gerrit] Change in coreboot[master]: drivers/i2c/generic: Support power resource as parent in device tree

[Tim Wawrzynczak (Code Review)]

Tim Wawrzynczak has uploaded this change for review. ( https://review.coreboot.org/c/coreboot/+/35075 )

Change subject: drivers/i2c/generic: Support power resource as parent in device tree
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drivers/i2c/generic: Support power resource as parent in device tree

This allows supporting an independent power resource for I2C generic
devices, so that the power resource configuration can be refactored
out of individual drivers and coalesced into a separate one.

Change-Id: I7554ab4fef88ffea0d3423ea27bb18a56b7f4de5
Signed-off-by: Tim Wawrzynczak 
---
M src/drivers/i2c/generic/generic.c
1 file changed, 16 insertions(+), 2 deletions(-)

git pull ssh://review.coreboot.org:29418/coreboot refs/changes/75/35075/1

diff --git a/src/drivers/i2c/generic/generic.c b/src/drivers/i2c/generic/generic.c
index 27ff9ff..a3411b0 100644
--- a/src/drivers/i2c/generic/generic.c
+++ b/src/drivers/i2c/generic/generic.c
@@ -23,6 +23,7 @@
 #include <stdint.h>
 #include <string.h>
 #include "chip.h"
+#include "drivers/generic/power_resource/chip.h"

#if CONFIG(HAVE_ACPI_TABLES)

@@ -59,7 +60,18 @@
    		void (*callback)(struct device *dev),
    		struct drivers_i2c_generic_config *config)
 {
-	const char *scope = acpi_device_scope(dev);
+	const int parent_is_power_resource =
+		CONFIG(DRIVERS_GENERIC_POWER_RESOURCE) &&
+		(dev->bus && dev->bus->children == dev &&
+		dev->bus->dev->chip_ops == &drivers_generic_power_resource_ops);
+	/*
+	 * Because the power resource is a "pseudo-device", we don't want it
+	 * to be included in the ACPI path
+	 */
+	const char *pr_scope = parent_is_power_resource ?
+		acpi_device_scope(dev->bus->dev) :
+		NULL;
+	const char *scope = (pr_scope == NULL) ? acpi_device_scope(dev) : pr_scope;
    struct acpi_i2c i2c = {
    	.address = dev->path.i2c.device,
    	.mode_10bit = dev->path.i2c.mode_10bit,
@@ -163,7 +175,9 @@
    		       acpi_device_path(dev));

acpi_add_device_power_resource("PRIC");
-
+	} else if (parent_is_power_resource) {
+		/* Parent device is a power resource, so set up _PR0/_PR3 */
+		acpi_add_device_power_resource(acpi_device_path(dev->bus->dev));
    }

/* Callback if any. */