From aba941392aeef2d1bc064a1e4b09293473ef7b9b Mon Sep 17 00:00:00 2001
From: Hans de Goede <hdegoede@redhat.com>
Date: Thu, 9 Aug 2018 11:15:56 +0200
Subject: [PATCH] ACPI / scan: Create platform device for fwnodes with multiple
 i2c devices
Git-commit: aba941392aeef2d1bc064a1e4b09293473ef7b9b
Patch-mainline: v4.19
References: FATE#326325

Some devices have multiple I2cSerialBus resources and for things to work
an i2c-client must be instantiated for each, each with its own
i2c_device_id.

Normally we only instantiate an i2c-client for the first resource, using
the ACPI HID as id.

This commit adds a list of HIDs of devices, which need multiple i2c-clients
instantiated from a single fwnode, to acpi_device_enumeration_by_parent and
makes acpi_device_enumeration_by_parent return false for these devices so
that a platform device will be instantiated.

This allows the drivers/platform/x86/i2c-multi-instantiate.c driver, which
knows which i2c_device_id to use for each resource, to bind to the fwnode
and initiate an i2c-client for each resource.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Oliver Neukum <oneukum@suse.com>
---
 drivers/acpi/scan.c |   16 ++++++++++++++++
 1 file changed, 16 insertions(+)

--- a/drivers/acpi/scan.c
+++ b/drivers/acpi/scan.c
@@ -1456,10 +1456,26 @@ static bool acpi_device_enumeration_by_p
 {
 	struct list_head resource_list;
 	bool is_serial_bus_slave = false;
+	/*
+	 * These devices have multiple I2cSerialBus resources and an i2c-client
+	 * must be instantiated for each, each with its own i2c_device_id.
+	 * Normally we only instantiate an i2c-client for the first resource,
+	 * using the ACPI HID as id. These special cases are handled by the
+	 * drivers/platform/x86/i2c-multi-instantiate.c driver, which knows
+	 * which i2c_device_id to use for each resource.
+	 */
+	static const struct acpi_device_id i2c_multi_instantiate_ids[] = {
+		{"BSG1160", },
+		{}
+	};
 
 	if (acpi_is_indirect_io_slave(device))
 		return true;
 
+	/* Instantiate a pdev for the i2c-multi-instantiate drv to bind to */
+	if (!acpi_match_device_ids(device, i2c_multi_instantiate_ids))
+		return false;
+
 	INIT_LIST_HEAD(&resource_list);
 	acpi_dev_get_resources(device, &resource_list,
 			       acpi_check_serial_bus_slave,