Merge branch 'i2c/for-4.4' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux

Pull i2c updates from Wolfram Sang:

 - New drivers: UniPhier (with and without FIFO)

 - some drivers got some bigger rework: ismt, designware, img-scb (rcar
   had to be reverted because issues were showing up just lately)

 - ACPI: reworked the device scanning and added support for muxes

... and quite a lot of driver bugfixes and cleanups this time.  All
files touched outside of the i2c realm have proper acks.

* 'i2c/for-4.4' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux: (70 commits)
  i2c: rcar: Revert the latest refactoring series
  i2c: pnx: remove superfluous assignment
  MAINTAINERS: i2c: drop i2c-pnx maintainer
  MAINTAINERS: i2c: mark also subdirectories as maintained
  i2c: cadence: enable driver for ARM64
  i2c: i801: Document Intel DNV and Broxton
  i2c: at91: manage unexpected RXRDY flag when starting a transfer
  i2c: pnx: Use setup_timer instead of open coding it
  i2c: add ACPI support for I2C mux ports
  acpi: add acpi_preset_companion() stub
  i2c: pxa: Add support for pxa910/988 & new configuration features
  i2c: au1550: Convert to devm_kzalloc and devm_ioremap_resource
  i2c-dev: Fix I2C_SLAVE ioctl comment
  i2c-dev: Fix typo in ioctl name reference
  i2c: sirf: tune the divider to make i2c bus freq more accurate
  i2c: imx: Use -ENXIO as error in the NACK case
  i2c: i801: Add support for Intel Broxton
  i2c: i801: Add support for Intel DNV
  i2c: mediatek: add i2c resume support
  i2c: imx: implement bus recovery
  ...

1 files changed, 59 insertions, 23 deletions

diff --git a/drivers/i2c/i2c-core.c b/drivers/i2c/i2c-core.c
index a59c3111f7fb..040af5cc8143 100644
--- a/drivers/i2c/i2c-core.c
+++ b/drivers/i2c/i2c-core.c
@@ -99,27 +99,40 @@ struct gsb_buffer {
         };
 } __packed;
 
-static int acpi_i2c_add_resource(struct acpi_resource *ares, void *data)
+struct acpi_i2c_lookup {
+        struct i2c_board_info *info;
+        acpi_handle adapter_handle;
+        acpi_handle device_handle;
+};
+
+static int acpi_i2c_find_address(struct acpi_resource *ares, void *data)
 {
-        struct i2c_board_info *info = data;
+        struct acpi_i2c_lookup *lookup = data;
+        struct i2c_board_info *info = lookup->info;
+        struct acpi_resource_i2c_serialbus *sb;
+        acpi_handle adapter_handle;
+        acpi_status status;
 
-        if (ares->type == ACPI_RESOURCE_TYPE_SERIAL_BUS) {
-                struct acpi_resource_i2c_serialbus *sb;
+        if (info->addr || ares->type != ACPI_RESOURCE_TYPE_SERIAL_BUS)
+                return 1;
 
-                sb = &ares->data.i2c_serial_bus;
-                if (!info->addr && sb->type == ACPI_RESOURCE_SERIAL_TYPE_I2C) {
-                        info->addr = sb->slave_address;
-                        if (sb->access_mode == ACPI_I2C_10BIT_MODE)
-                                info->flags |= I2C_CLIENT_TEN;
-                }
-        } else if (!info->irq) {
-                struct resource r;
+        sb = &ares->data.i2c_serial_bus;
+        if (sb->type != ACPI_RESOURCE_SERIAL_TYPE_I2C)
+                return 1;
 
-                if (acpi_dev_resource_interrupt(ares, 0, &r))
-                        info->irq = r.start;
+        /*
+         * Extract the ResourceSource and make sure that the handle matches
+         * with the I2C adapter handle.
+         */
+        status = acpi_get_handle(lookup->device_handle,
+                                 sb->resource_source.string_ptr,
+                                 &adapter_handle);
+        if (ACPI_SUCCESS(status) && adapter_handle == lookup->adapter_handle) {
+                info->addr = sb->slave_address;
+                if (sb->access_mode == ACPI_I2C_10BIT_MODE)
+                        info->flags |= I2C_CLIENT_TEN;
         }
 
-        /* Tell the ACPI core to skip this resource */
         return 1;
 }
 
@@ -128,6 +141,8 @@ static acpi_status acpi_i2c_add_device(acpi_handle handle, u32 level,
 {
         struct i2c_adapter *adapter = data;
         struct list_head resource_list;
+        struct acpi_i2c_lookup lookup;
+        struct resource_entry *entry;
         struct i2c_board_info info;
         struct acpi_device *adev;
         int ret;
@@ -140,14 +155,37 @@ static acpi_status acpi_i2c_add_device(acpi_handle handle, u32 level,
         memset(&info, 0, sizeof(info));
         info.fwnode = acpi_fwnode_handle(adev);
 
+        memset(&lookup, 0, sizeof(lookup));
+        lookup.adapter_handle = ACPI_HANDLE(&adapter->dev);
+        lookup.device_handle = handle;
+        lookup.info = &info;
+
+        /*
+         * Look up for I2cSerialBus resource with ResourceSource that
+         * matches with this adapter.
+         */
         INIT_LIST_HEAD(&resource_list);
         ret = acpi_dev_get_resources(adev, &resource_list,
-                                     acpi_i2c_add_resource, &info);
+                                     acpi_i2c_find_address, &lookup);
         acpi_dev_free_resource_list(&resource_list);
 
         if (ret < 0 || !info.addr)
                 return AE_OK;
 
+        /* Then fill IRQ number if any */
+        ret = acpi_dev_get_resources(adev, &resource_list, NULL, NULL);
+        if (ret < 0)
+                return AE_OK;
+
+        resource_list_for_each_entry(entry, &resource_list) {
+                if (resource_type(entry->res) == IORESOURCE_IRQ) {
+                        info.irq = entry->res->start;
+                        break;
+                }
+        }
+
+        acpi_dev_free_resource_list(&resource_list);
+
         adev->power.flags.ignore_parent = true;
         strlcpy(info.type, dev_name(&adev->dev), sizeof(info.type));
         if (!i2c_new_device(adapter, &info)) {
@@ -160,6 +198,8 @@ static acpi_status acpi_i2c_add_device(acpi_handle handle, u32 level,
         return AE_OK;
 }
 
+#define ACPI_I2C_MAX_SCAN_DEPTH 32
+
 /**
  * acpi_i2c_register_devices - enumerate I2C slave devices behind adapter
  * @adap: pointer to adapter
@@ -170,17 +210,13 @@ static acpi_status acpi_i2c_add_device(acpi_handle handle, u32 level,
  */
 static void acpi_i2c_register_devices(struct i2c_adapter *adap)
 {
-        acpi_handle handle;
         acpi_status status;
 
-        if (!adap->dev.parent)
-                return;
-
-        handle = ACPI_HANDLE(adap->dev.parent);
-        if (!handle)
+        if (!has_acpi_companion(&adap->dev))
                 return;
 
-        status = acpi_walk_namespace(ACPI_TYPE_DEVICE, handle, 1,
+        status = acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
+                                     ACPI_I2C_MAX_SCAN_DEPTH,
                                      acpi_i2c_add_device, NULL,
                                      adap, NULL);
         if (ACPI_FAILURE(status))