Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost

[firefly-linux-kernel-4.4.55.git] / drivers / acpi / scan.c

diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c
index ebbd23c94ba212791d81804bb7e406cc40d28376..f775fa0d850feee4996b7e90bd6158c379841e1b 100644 (file)
--- a/drivers/acpi/scan.c
+++ b/drivers/acpi/scan.c
@@ -84,7 +84,7 @@ EXPORT_SYMBOL_GPL(acpi_initialize_hp_context);
 
 int acpi_scan_add_handler(struct acpi_scan_handler *handler)
 {
-       if (!handler || !handler->attach)
+       if (!handler)
                return -EINVAL;
 
        list_add_tail(&handler->list_node, &acpi_scan_handlers_list);
@@ -2070,6 +2070,44 @@ 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;
+
+       if (!device->pnp.type.platform_id || device->handler)
+               return;
+
+       /*
+        * Do not enemerate SPI/I2C slaves as they will be enuerated 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)
+               acpi_create_platform_device(device);
+}
+
 static int acpi_scan_attach_handler(struct acpi_device *device)
 {
        struct acpi_hardware_id *hwid;
@@ -2081,6 +2119,10 @@ static int acpi_scan_attach_handler(struct acpi_device *device)
 
                handler = acpi_scan_match_handler(hwid->id, &devid);
                if (handler) {
+                       if (!handler->attach) {
+                               device->pnp.type.platform_id = 0;
+                               continue;
+                       }
                        device->handler = handler;
                        ret = handler->attach(device, devid);
                        if (ret > 0)
@@ -2091,6 +2133,9 @@ static int acpi_scan_attach_handler(struct acpi_device *device)
                                break;
                }
        }
+       if (!ret)
+               acpi_default_enumeration(device);
+
        return ret;
 }
 
@@ -2250,7 +2295,6 @@ int __init acpi_scan_init(void)
        acpi_pci_root_init();
        acpi_pci_link_init();
        acpi_processor_init();
-       acpi_platform_init();
        acpi_lpss_init();
        acpi_cmos_rtc_init();
        acpi_container_init();
@@ -2269,12 +2313,16 @@ int __init acpi_scan_init(void)
        if (result)
                goto out;
 
-       result = acpi_bus_scan_fixed();
-       if (result) {
-               acpi_detach_data(acpi_root->handle, acpi_scan_drop_device);
-               acpi_device_del(acpi_root);
-               put_device(&acpi_root->dev);
-               goto out;
+       /* Fixed feature devices do not exist on HW-reduced platform */
+       if (!acpi_gbl_reduced_hardware) {
+               result = acpi_bus_scan_fixed();
+               if (result) {
+                       acpi_detach_data(acpi_root->handle,
+                                        acpi_scan_drop_device);
+                       acpi_device_del(acpi_root);
+                       put_device(&acpi_root->dev);
+                       goto out;
+               }
        }
 
        acpi_update_all_gpes();