From: Lukas Wunner <lukas@wunner.de>
Date: Tue, 1 Aug 2017 12:10:41 +0000 (+0200)
Subject: ACPI / scan: Recognize Apple SPI and I2C slaves
X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=ca9ef3ab68d3530ac93d4254f9e47724ea51758d;p=GitHub%2FLineageOS%2Fandroid_kernel_motorola_exynos9610.git

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 33897298f03e..55fd248833cd 100644
--- 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);