Merge tag 'acpi-4.12-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull ACPI fix from Rafael Wysocki:
 "This fixes the ACPI-based enumeration of some I2C and SPI devices
  broken in 4.11.

  Specifics:

   - I2C and SPI devices are expected to be enumerated by the I2C and
     SPI subsystems, respectively, but due to a change made during the
     4.11 cycle, in some cases the ACPI core marks them as already
     enumerated which causes the I2C and SPI subsystems to overlook
     them, so fix that (Jarkko Nikula)"

* tag 'acpi-4.12-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  ACPI / scan: Fix enumeration for special SPI and I2C devices

2 files changed, 39 insertions, 31 deletions

diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c
index 3a10d7573477..d53162997f32 100644
--- a/drivers/acpi/scan.c
+++ b/drivers/acpi/scan.c
@@ -1428,6 +1428,37 @@ static void acpi_init_coherency(struct acpi_device *adev)
 	adev->flags.coherent_dma = cca;
 }
 
+static int acpi_check_spi_i2c_slave(struct acpi_resource *ares, void *data)
+{
+	bool *is_spi_i2c_slave_p = data;
+
+	if (ares->type != ACPI_RESOURCE_TYPE_SERIAL_BUS)
+		return 1;
+
+	/*
+	 * devices that are connected to UART still need to be enumerated to
+	 * platform bus
+	 */
+	if (ares->data.common_serial_bus.type != ACPI_RESOURCE_SERIAL_TYPE_UART)
+		*is_spi_i2c_slave_p = true;
+
+	 /* no need to do more checking */
+	return -1;
+}
+
+static bool acpi_is_spi_i2c_slave(struct acpi_device *device)
+{
+	struct list_head resource_list;
+	bool is_spi_i2c_slave = false;
+
+	INIT_LIST_HEAD(&resource_list);
+	acpi_dev_get_resources(device, &resource_list, acpi_check_spi_i2c_slave,
+			       &is_spi_i2c_slave);
+	acpi_dev_free_resource_list(&resource_list);
+
+	return is_spi_i2c_slave;
+}
+
 void acpi_init_device_object(struct acpi_device *device, acpi_handle handle,
 			     int type, unsigned long long sta)
 {
@@ -1443,6 +1474,7 @@ void acpi_init_device_object(struct acpi_device *device, acpi_handle handle,
 	acpi_bus_get_flags(device);
 	device->flags.match_driver = false;
 	device->flags.initialized = true;
+	device->flags.spi_i2c_slave = acpi_is_spi_i2c_slave(device);
 	acpi_device_clear_enumerated(device);
 	device_initialize(&device->dev);
 	dev_set_uevent_suppress(&device->dev, true);
@@ -1727,38 +1759,13 @@ static acpi_status acpi_bus_check_add(acpi_handle handle, u32 lvl_not_used,
 	return AE_OK;
 }
 
-static int acpi_check_spi_i2c_slave(struct acpi_resource *ares, void *data)
-{
-	bool *is_spi_i2c_slave_p = data;
-
-	if (ares->type != ACPI_RESOURCE_TYPE_SERIAL_BUS)
-		return 1;
-
-	/*
-	 * devices that are connected to UART still need to be enumerated to
-	 * platform bus
-	 */
-	if (ares->data.common_serial_bus.type != ACPI_RESOURCE_SERIAL_TYPE_UART)
-		*is_spi_i2c_slave_p = true;
-
-	 /* no need to do more checking */
-	return -1;
-}
-
 static void acpi_default_enumeration(struct acpi_device *device)
 {
-	struct list_head resource_list;
-	bool is_spi_i2c_slave = false;
-
 	/*
 	 * Do not enumerate SPI/I2C slaves as they will be enumerated by their
 	 * respective parents.
 	 */
-	INIT_LIST_HEAD(&resource_list);
-	acpi_dev_get_resources(device, &resource_list, acpi_check_spi_i2c_slave,
-			       &is_spi_i2c_slave);
-	acpi_dev_free_resource_list(&resource_list);
-	if (!is_spi_i2c_slave) {
+	if (!device->flags.spi_i2c_slave) {
 		acpi_create_platform_device(device, NULL);
 		acpi_device_set_enumerated(device);
 	} else {
@@ -1854,7 +1861,7 @@ static void acpi_bus_attach(struct acpi_device *device)
 		return;
 
 	device->flags.match_driver = true;
-	if (ret > 0) {
+	if (ret > 0 && !device->flags.spi_i2c_slave) {
 		acpi_device_set_enumerated(device);
 		goto ok;
 	}
@@ -1863,10 +1870,10 @@ static void acpi_bus_attach(struct acpi_device *device)
 	if (ret < 0)
 		return;
 
-	if (device->pnp.type.platform_id)
-		acpi_default_enumeration(device);
-	else
+	if (!device->pnp.type.platform_id && !device->flags.spi_i2c_slave)
 		acpi_device_set_enumerated(device);
+	else
+		acpi_default_enumeration(device);
 
  ok:
 	list_for_each_entry(child, &device->children, node)
diff --git a/include/acpi/acpi_bus.h b/include/acpi/acpi_bus.h
index 197f3fffc9a7..408c7820e200 100644
--- a/include/acpi/acpi_bus.h
+++ b/include/acpi/acpi_bus.h
@@ -210,7 +210,8 @@ struct acpi_device_flags {
 	u32 of_compatible_ok:1;
 	u32 coherent_dma:1;
 	u32 cca_seen:1;
-	u32 reserved:20;
+	u32 spi_i2c_slave:1;
+	u32 reserved:19;
 };
 
 /* File System */