ACPI / scan: Recognize Apple SPI and I2C slaves

SPI and I2C slaves are enumerated by their respective parents rather
than the ACPI core.  They are recognized by presence of _CRS resources,
which however are missing on Macs.  Check for presence of device
properties instead.

Reported-and-tested-by: Ronald Tschalär <ronald@innovation.ch>
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c
index 33897298f03e3ed680272ba6f4109077d434a0d8..55fd248833cd56af4796c3282486a7922ef0e2b1 100644 (file)
--- a/drivers/acpi/scan.c
+++ b/drivers/acpi/scan.c
@@ -13,6 +13,7 @@
 #include <linux/dmi.h>
 #include <linux/nls.h>
 #include <linux/dma-mapping.h>
+#include <linux/platform_data/x86/apple.h>
 
 #include <asm/pgtable.h>
 
@@ -1452,6 +1453,12 @@ static bool acpi_is_spi_i2c_slave(struct acpi_device *device)
        struct list_head resource_list;
        bool is_spi_i2c_slave = false;
 
+       /* Macs use device properties in lieu of _CRS resources */
+       if (x86_apple_machine &&
+           (fwnode_property_present(&device->fwnode, "spiSclkPeriod") ||
+            fwnode_property_present(&device->fwnode, "i2cAddress")))
+               return true;
+
        INIT_LIST_HEAD(&resource_list);
        acpi_dev_get_resources(device, &resource_list, acpi_check_spi_i2c_slave,
                               &is_spi_i2c_slave);