xref: /linux/drivers/i2c/i2c-core-acpi.c (revision c64ffff7a9d1eee6624d3eaab36968fe6df31a9f)
153f8f7c5SWolfram Sang /*
253f8f7c5SWolfram Sang  * Linux I2C core ACPI support code
353f8f7c5SWolfram Sang  *
453f8f7c5SWolfram Sang  * Copyright (C) 2014 Intel Corp, Author: Lan Tianyu <tianyu.lan@intel.com>
553f8f7c5SWolfram Sang  *
653f8f7c5SWolfram Sang  * This program is free software; you can redistribute it and/or modify it
753f8f7c5SWolfram Sang  * under the terms of the GNU General Public License as published by the Free
853f8f7c5SWolfram Sang  * Software Foundation; either version 2 of the License, or (at your option)
953f8f7c5SWolfram Sang  * any later version.
1053f8f7c5SWolfram Sang  */
1153f8f7c5SWolfram Sang 
1253f8f7c5SWolfram Sang #include <linux/acpi.h>
1353f8f7c5SWolfram Sang #include <linux/device.h>
1453f8f7c5SWolfram Sang #include <linux/err.h>
1553f8f7c5SWolfram Sang #include <linux/i2c.h>
1653f8f7c5SWolfram Sang #include <linux/list.h>
1753f8f7c5SWolfram Sang #include <linux/module.h>
1853f8f7c5SWolfram Sang #include <linux/slab.h>
1953f8f7c5SWolfram Sang 
2053f8f7c5SWolfram Sang #include "i2c-core.h"
2153f8f7c5SWolfram Sang 
2253f8f7c5SWolfram Sang struct i2c_acpi_handler_data {
2353f8f7c5SWolfram Sang 	struct acpi_connection_info info;
2453f8f7c5SWolfram Sang 	struct i2c_adapter *adapter;
2553f8f7c5SWolfram Sang };
2653f8f7c5SWolfram Sang 
2753f8f7c5SWolfram Sang struct gsb_buffer {
2853f8f7c5SWolfram Sang 	u8	status;
2953f8f7c5SWolfram Sang 	u8	len;
3053f8f7c5SWolfram Sang 	union {
3153f8f7c5SWolfram Sang 		u16	wdata;
3253f8f7c5SWolfram Sang 		u8	bdata;
3353f8f7c5SWolfram Sang 		u8	data[0];
3453f8f7c5SWolfram Sang 	};
3553f8f7c5SWolfram Sang } __packed;
3653f8f7c5SWolfram Sang 
3753f8f7c5SWolfram Sang struct i2c_acpi_lookup {
3853f8f7c5SWolfram Sang 	struct i2c_board_info *info;
3953f8f7c5SWolfram Sang 	acpi_handle adapter_handle;
4053f8f7c5SWolfram Sang 	acpi_handle device_handle;
4153f8f7c5SWolfram Sang 	acpi_handle search_handle;
4253f8f7c5SWolfram Sang 	int n;
4353f8f7c5SWolfram Sang 	int index;
4453f8f7c5SWolfram Sang 	u32 speed;
4553f8f7c5SWolfram Sang 	u32 min_speed;
4653f8f7c5SWolfram Sang };
4753f8f7c5SWolfram Sang 
4853f8f7c5SWolfram Sang static int i2c_acpi_fill_info(struct acpi_resource *ares, void *data)
4953f8f7c5SWolfram Sang {
5053f8f7c5SWolfram Sang 	struct i2c_acpi_lookup *lookup = data;
5153f8f7c5SWolfram Sang 	struct i2c_board_info *info = lookup->info;
5253f8f7c5SWolfram Sang 	struct acpi_resource_i2c_serialbus *sb;
5353f8f7c5SWolfram Sang 	acpi_status status;
5453f8f7c5SWolfram Sang 
5553f8f7c5SWolfram Sang 	if (info->addr || ares->type != ACPI_RESOURCE_TYPE_SERIAL_BUS)
5653f8f7c5SWolfram Sang 		return 1;
5753f8f7c5SWolfram Sang 
5853f8f7c5SWolfram Sang 	sb = &ares->data.i2c_serial_bus;
5953f8f7c5SWolfram Sang 	if (sb->type != ACPI_RESOURCE_SERIAL_TYPE_I2C)
6053f8f7c5SWolfram Sang 		return 1;
6153f8f7c5SWolfram Sang 
6253f8f7c5SWolfram Sang 	if (lookup->index != -1 && lookup->n++ != lookup->index)
6353f8f7c5SWolfram Sang 		return 1;
6453f8f7c5SWolfram Sang 
6553f8f7c5SWolfram Sang 	status = acpi_get_handle(lookup->device_handle,
6653f8f7c5SWolfram Sang 				 sb->resource_source.string_ptr,
6753f8f7c5SWolfram Sang 				 &lookup->adapter_handle);
6853f8f7c5SWolfram Sang 	if (!ACPI_SUCCESS(status))
6953f8f7c5SWolfram Sang 		return 1;
7053f8f7c5SWolfram Sang 
7153f8f7c5SWolfram Sang 	info->addr = sb->slave_address;
7253f8f7c5SWolfram Sang 	lookup->speed = sb->connection_speed;
7353f8f7c5SWolfram Sang 	if (sb->access_mode == ACPI_I2C_10BIT_MODE)
7453f8f7c5SWolfram Sang 		info->flags |= I2C_CLIENT_TEN;
7553f8f7c5SWolfram Sang 
7653f8f7c5SWolfram Sang 	return 1;
7753f8f7c5SWolfram Sang }
7853f8f7c5SWolfram Sang 
793a4991a9SHans de Goede static const struct acpi_device_id i2c_acpi_ignored_device_ids[] = {
803a4991a9SHans de Goede 	/*
813a4991a9SHans de Goede 	 * ACPI video acpi_devices, which are handled by the acpi-video driver
823a4991a9SHans de Goede 	 * sometimes contain a SERIAL_TYPE_I2C ACPI resource, ignore these.
833a4991a9SHans de Goede 	 */
843a4991a9SHans de Goede 	{ ACPI_VIDEO_HID, 0 },
853a4991a9SHans de Goede 	{}
863a4991a9SHans de Goede };
873a4991a9SHans de Goede 
8853f8f7c5SWolfram Sang static int i2c_acpi_do_lookup(struct acpi_device *adev,
8953f8f7c5SWolfram Sang 			      struct i2c_acpi_lookup *lookup)
9053f8f7c5SWolfram Sang {
9153f8f7c5SWolfram Sang 	struct i2c_board_info *info = lookup->info;
9253f8f7c5SWolfram Sang 	struct list_head resource_list;
9353f8f7c5SWolfram Sang 	int ret;
9453f8f7c5SWolfram Sang 
9553f8f7c5SWolfram Sang 	if (acpi_bus_get_status(adev) || !adev->status.present ||
9653f8f7c5SWolfram Sang 	    acpi_device_enumerated(adev))
9753f8f7c5SWolfram Sang 		return -EINVAL;
9853f8f7c5SWolfram Sang 
993a4991a9SHans de Goede 	if (acpi_match_device_ids(adev, i2c_acpi_ignored_device_ids) == 0)
1003a4991a9SHans de Goede 		return -ENODEV;
1013a4991a9SHans de Goede 
10253f8f7c5SWolfram Sang 	memset(info, 0, sizeof(*info));
10353f8f7c5SWolfram Sang 	lookup->device_handle = acpi_device_handle(adev);
10453f8f7c5SWolfram Sang 
10553f8f7c5SWolfram Sang 	/* Look up for I2cSerialBus resource */
10653f8f7c5SWolfram Sang 	INIT_LIST_HEAD(&resource_list);
10753f8f7c5SWolfram Sang 	ret = acpi_dev_get_resources(adev, &resource_list,
10853f8f7c5SWolfram Sang 				     i2c_acpi_fill_info, lookup);
10953f8f7c5SWolfram Sang 	acpi_dev_free_resource_list(&resource_list);
11053f8f7c5SWolfram Sang 
11153f8f7c5SWolfram Sang 	if (ret < 0 || !info->addr)
11253f8f7c5SWolfram Sang 		return -EINVAL;
11353f8f7c5SWolfram Sang 
11453f8f7c5SWolfram Sang 	return 0;
11553f8f7c5SWolfram Sang }
11653f8f7c5SWolfram Sang 
11753f8f7c5SWolfram Sang static int i2c_acpi_get_info(struct acpi_device *adev,
11853f8f7c5SWolfram Sang 			     struct i2c_board_info *info,
11953f8f7c5SWolfram Sang 			     struct i2c_adapter *adapter,
12053f8f7c5SWolfram Sang 			     acpi_handle *adapter_handle)
12153f8f7c5SWolfram Sang {
12253f8f7c5SWolfram Sang 	struct list_head resource_list;
12353f8f7c5SWolfram Sang 	struct resource_entry *entry;
12453f8f7c5SWolfram Sang 	struct i2c_acpi_lookup lookup;
12553f8f7c5SWolfram Sang 	int ret;
12653f8f7c5SWolfram Sang 
12753f8f7c5SWolfram Sang 	memset(&lookup, 0, sizeof(lookup));
12853f8f7c5SWolfram Sang 	lookup.info = info;
12953f8f7c5SWolfram Sang 	lookup.index = -1;
13053f8f7c5SWolfram Sang 
13153f8f7c5SWolfram Sang 	ret = i2c_acpi_do_lookup(adev, &lookup);
13253f8f7c5SWolfram Sang 	if (ret)
13353f8f7c5SWolfram Sang 		return ret;
13453f8f7c5SWolfram Sang 
13553f8f7c5SWolfram Sang 	if (adapter) {
13653f8f7c5SWolfram Sang 		/* The adapter must match the one in I2cSerialBus() connector */
13753f8f7c5SWolfram Sang 		if (ACPI_HANDLE(&adapter->dev) != lookup.adapter_handle)
13853f8f7c5SWolfram Sang 			return -ENODEV;
13953f8f7c5SWolfram Sang 	} else {
14053f8f7c5SWolfram Sang 		struct acpi_device *adapter_adev;
14153f8f7c5SWolfram Sang 
14253f8f7c5SWolfram Sang 		/* The adapter must be present */
14353f8f7c5SWolfram Sang 		if (acpi_bus_get_device(lookup.adapter_handle, &adapter_adev))
14453f8f7c5SWolfram Sang 			return -ENODEV;
14553f8f7c5SWolfram Sang 		if (acpi_bus_get_status(adapter_adev) ||
14653f8f7c5SWolfram Sang 		    !adapter_adev->status.present)
14753f8f7c5SWolfram Sang 			return -ENODEV;
14853f8f7c5SWolfram Sang 	}
14953f8f7c5SWolfram Sang 
15053f8f7c5SWolfram Sang 	info->fwnode = acpi_fwnode_handle(adev);
15153f8f7c5SWolfram Sang 	if (adapter_handle)
15253f8f7c5SWolfram Sang 		*adapter_handle = lookup.adapter_handle;
15353f8f7c5SWolfram Sang 
15453f8f7c5SWolfram Sang 	/* Then fill IRQ number if any */
15553f8f7c5SWolfram Sang 	INIT_LIST_HEAD(&resource_list);
15653f8f7c5SWolfram Sang 	ret = acpi_dev_get_resources(adev, &resource_list, NULL, NULL);
15753f8f7c5SWolfram Sang 	if (ret < 0)
15853f8f7c5SWolfram Sang 		return -EINVAL;
15953f8f7c5SWolfram Sang 
16053f8f7c5SWolfram Sang 	resource_list_for_each_entry(entry, &resource_list) {
16153f8f7c5SWolfram Sang 		if (resource_type(entry->res) == IORESOURCE_IRQ) {
16253f8f7c5SWolfram Sang 			info->irq = entry->res->start;
16353f8f7c5SWolfram Sang 			break;
16453f8f7c5SWolfram Sang 		}
16553f8f7c5SWolfram Sang 	}
16653f8f7c5SWolfram Sang 
16753f8f7c5SWolfram Sang 	acpi_dev_free_resource_list(&resource_list);
16853f8f7c5SWolfram Sang 
16953f8f7c5SWolfram Sang 	acpi_set_modalias(adev, dev_name(&adev->dev), info->type,
17053f8f7c5SWolfram Sang 			  sizeof(info->type));
17153f8f7c5SWolfram Sang 
17253f8f7c5SWolfram Sang 	return 0;
17353f8f7c5SWolfram Sang }
17453f8f7c5SWolfram Sang 
17553f8f7c5SWolfram Sang static void i2c_acpi_register_device(struct i2c_adapter *adapter,
17653f8f7c5SWolfram Sang 				     struct acpi_device *adev,
17753f8f7c5SWolfram Sang 				     struct i2c_board_info *info)
17853f8f7c5SWolfram Sang {
17953f8f7c5SWolfram Sang 	adev->power.flags.ignore_parent = true;
18053f8f7c5SWolfram Sang 	acpi_device_set_enumerated(adev);
18153f8f7c5SWolfram Sang 
18253f8f7c5SWolfram Sang 	if (!i2c_new_device(adapter, info)) {
18353f8f7c5SWolfram Sang 		adev->power.flags.ignore_parent = false;
18453f8f7c5SWolfram Sang 		dev_err(&adapter->dev,
18553f8f7c5SWolfram Sang 			"failed to add I2C device %s from ACPI\n",
18653f8f7c5SWolfram Sang 			dev_name(&adev->dev));
18753f8f7c5SWolfram Sang 	}
18853f8f7c5SWolfram Sang }
18953f8f7c5SWolfram Sang 
19053f8f7c5SWolfram Sang static acpi_status i2c_acpi_add_device(acpi_handle handle, u32 level,
19153f8f7c5SWolfram Sang 				       void *data, void **return_value)
19253f8f7c5SWolfram Sang {
19353f8f7c5SWolfram Sang 	struct i2c_adapter *adapter = data;
19453f8f7c5SWolfram Sang 	struct acpi_device *adev;
19553f8f7c5SWolfram Sang 	struct i2c_board_info info;
19653f8f7c5SWolfram Sang 
19753f8f7c5SWolfram Sang 	if (acpi_bus_get_device(handle, &adev))
19853f8f7c5SWolfram Sang 		return AE_OK;
19953f8f7c5SWolfram Sang 
20053f8f7c5SWolfram Sang 	if (i2c_acpi_get_info(adev, &info, adapter, NULL))
20153f8f7c5SWolfram Sang 		return AE_OK;
20253f8f7c5SWolfram Sang 
20353f8f7c5SWolfram Sang 	i2c_acpi_register_device(adapter, adev, &info);
20453f8f7c5SWolfram Sang 
20553f8f7c5SWolfram Sang 	return AE_OK;
20653f8f7c5SWolfram Sang }
20753f8f7c5SWolfram Sang 
20853f8f7c5SWolfram Sang #define I2C_ACPI_MAX_SCAN_DEPTH 32
20953f8f7c5SWolfram Sang 
21053f8f7c5SWolfram Sang /**
21153f8f7c5SWolfram Sang  * i2c_acpi_register_devices - enumerate I2C slave devices behind adapter
21253f8f7c5SWolfram Sang  * @adap: pointer to adapter
21353f8f7c5SWolfram Sang  *
21453f8f7c5SWolfram Sang  * Enumerate all I2C slave devices behind this adapter by walking the ACPI
21553f8f7c5SWolfram Sang  * namespace. When a device is found it will be added to the Linux device
21653f8f7c5SWolfram Sang  * model and bound to the corresponding ACPI handle.
21753f8f7c5SWolfram Sang  */
21853f8f7c5SWolfram Sang void i2c_acpi_register_devices(struct i2c_adapter *adap)
21953f8f7c5SWolfram Sang {
22053f8f7c5SWolfram Sang 	acpi_status status;
22153f8f7c5SWolfram Sang 
22253f8f7c5SWolfram Sang 	if (!has_acpi_companion(&adap->dev))
22353f8f7c5SWolfram Sang 		return;
22453f8f7c5SWolfram Sang 
22553f8f7c5SWolfram Sang 	status = acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
22653f8f7c5SWolfram Sang 				     I2C_ACPI_MAX_SCAN_DEPTH,
22753f8f7c5SWolfram Sang 				     i2c_acpi_add_device, NULL,
22853f8f7c5SWolfram Sang 				     adap, NULL);
22953f8f7c5SWolfram Sang 	if (ACPI_FAILURE(status))
23053f8f7c5SWolfram Sang 		dev_warn(&adap->dev, "failed to enumerate I2C slaves\n");
23153f8f7c5SWolfram Sang }
23253f8f7c5SWolfram Sang 
233*c64ffff7SAndy Shevchenko const struct acpi_device_id *
234*c64ffff7SAndy Shevchenko i2c_acpi_match_device(const struct acpi_device_id *matches,
235*c64ffff7SAndy Shevchenko 		      struct i2c_client *client)
236*c64ffff7SAndy Shevchenko {
237*c64ffff7SAndy Shevchenko 	if (!(client && matches))
238*c64ffff7SAndy Shevchenko 		return NULL;
239*c64ffff7SAndy Shevchenko 
240*c64ffff7SAndy Shevchenko 	return acpi_match_device(matches, &client->dev);
241*c64ffff7SAndy Shevchenko }
242*c64ffff7SAndy Shevchenko 
24353f8f7c5SWolfram Sang static acpi_status i2c_acpi_lookup_speed(acpi_handle handle, u32 level,
24453f8f7c5SWolfram Sang 					   void *data, void **return_value)
24553f8f7c5SWolfram Sang {
24653f8f7c5SWolfram Sang 	struct i2c_acpi_lookup *lookup = data;
24753f8f7c5SWolfram Sang 	struct acpi_device *adev;
24853f8f7c5SWolfram Sang 
24953f8f7c5SWolfram Sang 	if (acpi_bus_get_device(handle, &adev))
25053f8f7c5SWolfram Sang 		return AE_OK;
25153f8f7c5SWolfram Sang 
25253f8f7c5SWolfram Sang 	if (i2c_acpi_do_lookup(adev, lookup))
25353f8f7c5SWolfram Sang 		return AE_OK;
25453f8f7c5SWolfram Sang 
25553f8f7c5SWolfram Sang 	if (lookup->search_handle != lookup->adapter_handle)
25653f8f7c5SWolfram Sang 		return AE_OK;
25753f8f7c5SWolfram Sang 
25853f8f7c5SWolfram Sang 	if (lookup->speed <= lookup->min_speed)
25953f8f7c5SWolfram Sang 		lookup->min_speed = lookup->speed;
26053f8f7c5SWolfram Sang 
26153f8f7c5SWolfram Sang 	return AE_OK;
26253f8f7c5SWolfram Sang }
26353f8f7c5SWolfram Sang 
26453f8f7c5SWolfram Sang /**
26553f8f7c5SWolfram Sang  * i2c_acpi_find_bus_speed - find I2C bus speed from ACPI
26653f8f7c5SWolfram Sang  * @dev: The device owning the bus
26753f8f7c5SWolfram Sang  *
26853f8f7c5SWolfram Sang  * Find the I2C bus speed by walking the ACPI namespace for all I2C slaves
26953f8f7c5SWolfram Sang  * devices connected to this bus and use the speed of slowest device.
27053f8f7c5SWolfram Sang  *
27153f8f7c5SWolfram Sang  * Returns the speed in Hz or zero
27253f8f7c5SWolfram Sang  */
27353f8f7c5SWolfram Sang u32 i2c_acpi_find_bus_speed(struct device *dev)
27453f8f7c5SWolfram Sang {
27553f8f7c5SWolfram Sang 	struct i2c_acpi_lookup lookup;
27653f8f7c5SWolfram Sang 	struct i2c_board_info dummy;
27753f8f7c5SWolfram Sang 	acpi_status status;
27853f8f7c5SWolfram Sang 
27953f8f7c5SWolfram Sang 	if (!has_acpi_companion(dev))
28053f8f7c5SWolfram Sang 		return 0;
28153f8f7c5SWolfram Sang 
28253f8f7c5SWolfram Sang 	memset(&lookup, 0, sizeof(lookup));
28353f8f7c5SWolfram Sang 	lookup.search_handle = ACPI_HANDLE(dev);
28453f8f7c5SWolfram Sang 	lookup.min_speed = UINT_MAX;
28553f8f7c5SWolfram Sang 	lookup.info = &dummy;
28653f8f7c5SWolfram Sang 	lookup.index = -1;
28753f8f7c5SWolfram Sang 
28853f8f7c5SWolfram Sang 	status = acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
28953f8f7c5SWolfram Sang 				     I2C_ACPI_MAX_SCAN_DEPTH,
29053f8f7c5SWolfram Sang 				     i2c_acpi_lookup_speed, NULL,
29153f8f7c5SWolfram Sang 				     &lookup, NULL);
29253f8f7c5SWolfram Sang 
29353f8f7c5SWolfram Sang 	if (ACPI_FAILURE(status)) {
29453f8f7c5SWolfram Sang 		dev_warn(dev, "unable to find I2C bus speed from ACPI\n");
29553f8f7c5SWolfram Sang 		return 0;
29653f8f7c5SWolfram Sang 	}
29753f8f7c5SWolfram Sang 
29853f8f7c5SWolfram Sang 	return lookup.min_speed != UINT_MAX ? lookup.min_speed : 0;
29953f8f7c5SWolfram Sang }
30053f8f7c5SWolfram Sang EXPORT_SYMBOL_GPL(i2c_acpi_find_bus_speed);
30153f8f7c5SWolfram Sang 
302*c64ffff7SAndy Shevchenko static int i2c_acpi_find_match_adapter(struct device *dev, void *data)
30353f8f7c5SWolfram Sang {
30453f8f7c5SWolfram Sang 	struct i2c_adapter *adapter = i2c_verify_adapter(dev);
30553f8f7c5SWolfram Sang 
30653f8f7c5SWolfram Sang 	if (!adapter)
30753f8f7c5SWolfram Sang 		return 0;
30853f8f7c5SWolfram Sang 
30953f8f7c5SWolfram Sang 	return ACPI_HANDLE(dev) == (acpi_handle)data;
31053f8f7c5SWolfram Sang }
31153f8f7c5SWolfram Sang 
312*c64ffff7SAndy Shevchenko static int i2c_acpi_find_match_device(struct device *dev, void *data)
31353f8f7c5SWolfram Sang {
31453f8f7c5SWolfram Sang 	return ACPI_COMPANION(dev) == data;
31553f8f7c5SWolfram Sang }
31653f8f7c5SWolfram Sang 
31753f8f7c5SWolfram Sang static struct i2c_adapter *i2c_acpi_find_adapter_by_handle(acpi_handle handle)
31853f8f7c5SWolfram Sang {
31953f8f7c5SWolfram Sang 	struct device *dev;
32053f8f7c5SWolfram Sang 
32153f8f7c5SWolfram Sang 	dev = bus_find_device(&i2c_bus_type, NULL, handle,
322*c64ffff7SAndy Shevchenko 			      i2c_acpi_find_match_adapter);
32353f8f7c5SWolfram Sang 	return dev ? i2c_verify_adapter(dev) : NULL;
32453f8f7c5SWolfram Sang }
32553f8f7c5SWolfram Sang 
32653f8f7c5SWolfram Sang static struct i2c_client *i2c_acpi_find_client_by_adev(struct acpi_device *adev)
32753f8f7c5SWolfram Sang {
32853f8f7c5SWolfram Sang 	struct device *dev;
32953f8f7c5SWolfram Sang 
330*c64ffff7SAndy Shevchenko 	dev = bus_find_device(&i2c_bus_type, NULL, adev,
331*c64ffff7SAndy Shevchenko 			      i2c_acpi_find_match_device);
33253f8f7c5SWolfram Sang 	return dev ? i2c_verify_client(dev) : NULL;
33353f8f7c5SWolfram Sang }
33453f8f7c5SWolfram Sang 
33553f8f7c5SWolfram Sang static int i2c_acpi_notify(struct notifier_block *nb, unsigned long value,
33653f8f7c5SWolfram Sang 			   void *arg)
33753f8f7c5SWolfram Sang {
33853f8f7c5SWolfram Sang 	struct acpi_device *adev = arg;
33953f8f7c5SWolfram Sang 	struct i2c_board_info info;
34053f8f7c5SWolfram Sang 	acpi_handle adapter_handle;
34153f8f7c5SWolfram Sang 	struct i2c_adapter *adapter;
34253f8f7c5SWolfram Sang 	struct i2c_client *client;
34353f8f7c5SWolfram Sang 
34453f8f7c5SWolfram Sang 	switch (value) {
34553f8f7c5SWolfram Sang 	case ACPI_RECONFIG_DEVICE_ADD:
34653f8f7c5SWolfram Sang 		if (i2c_acpi_get_info(adev, &info, NULL, &adapter_handle))
34753f8f7c5SWolfram Sang 			break;
34853f8f7c5SWolfram Sang 
34953f8f7c5SWolfram Sang 		adapter = i2c_acpi_find_adapter_by_handle(adapter_handle);
35053f8f7c5SWolfram Sang 		if (!adapter)
35153f8f7c5SWolfram Sang 			break;
35253f8f7c5SWolfram Sang 
35353f8f7c5SWolfram Sang 		i2c_acpi_register_device(adapter, adev, &info);
35453f8f7c5SWolfram Sang 		break;
35553f8f7c5SWolfram Sang 	case ACPI_RECONFIG_DEVICE_REMOVE:
35653f8f7c5SWolfram Sang 		if (!acpi_device_enumerated(adev))
35753f8f7c5SWolfram Sang 			break;
35853f8f7c5SWolfram Sang 
35953f8f7c5SWolfram Sang 		client = i2c_acpi_find_client_by_adev(adev);
36053f8f7c5SWolfram Sang 		if (!client)
36153f8f7c5SWolfram Sang 			break;
36253f8f7c5SWolfram Sang 
36353f8f7c5SWolfram Sang 		i2c_unregister_device(client);
36453f8f7c5SWolfram Sang 		put_device(&client->dev);
36553f8f7c5SWolfram Sang 		break;
36653f8f7c5SWolfram Sang 	}
36753f8f7c5SWolfram Sang 
36853f8f7c5SWolfram Sang 	return NOTIFY_OK;
36953f8f7c5SWolfram Sang }
37053f8f7c5SWolfram Sang 
37153f8f7c5SWolfram Sang struct notifier_block i2c_acpi_notifier = {
37253f8f7c5SWolfram Sang 	.notifier_call = i2c_acpi_notify,
37353f8f7c5SWolfram Sang };
37453f8f7c5SWolfram Sang 
37553f8f7c5SWolfram Sang /**
37653f8f7c5SWolfram Sang  * i2c_acpi_new_device - Create i2c-client for the Nth I2cSerialBus resource
37753f8f7c5SWolfram Sang  * @dev:     Device owning the ACPI resources to get the client from
37853f8f7c5SWolfram Sang  * @index:   Index of ACPI resource to get
37953f8f7c5SWolfram Sang  * @info:    describes the I2C device; note this is modified (addr gets set)
38053f8f7c5SWolfram Sang  * Context: can sleep
38153f8f7c5SWolfram Sang  *
38253f8f7c5SWolfram Sang  * By default the i2c subsys creates an i2c-client for the first I2cSerialBus
38353f8f7c5SWolfram Sang  * resource of an acpi_device, but some acpi_devices have multiple I2cSerialBus
38453f8f7c5SWolfram Sang  * resources, in that case this function can be used to create an i2c-client
38553f8f7c5SWolfram Sang  * for other I2cSerialBus resources in the Current Resource Settings table.
38653f8f7c5SWolfram Sang  *
38753f8f7c5SWolfram Sang  * Also see i2c_new_device, which this function calls to create the i2c-client.
38853f8f7c5SWolfram Sang  *
38953f8f7c5SWolfram Sang  * Returns a pointer to the new i2c-client, or NULL if the adapter is not found.
39053f8f7c5SWolfram Sang  */
39153f8f7c5SWolfram Sang struct i2c_client *i2c_acpi_new_device(struct device *dev, int index,
39253f8f7c5SWolfram Sang 				       struct i2c_board_info *info)
39353f8f7c5SWolfram Sang {
39453f8f7c5SWolfram Sang 	struct i2c_acpi_lookup lookup;
39553f8f7c5SWolfram Sang 	struct i2c_adapter *adapter;
39653f8f7c5SWolfram Sang 	struct acpi_device *adev;
39753f8f7c5SWolfram Sang 	LIST_HEAD(resource_list);
39853f8f7c5SWolfram Sang 	int ret;
39953f8f7c5SWolfram Sang 
40053f8f7c5SWolfram Sang 	adev = ACPI_COMPANION(dev);
40153f8f7c5SWolfram Sang 	if (!adev)
40253f8f7c5SWolfram Sang 		return NULL;
40353f8f7c5SWolfram Sang 
40453f8f7c5SWolfram Sang 	memset(&lookup, 0, sizeof(lookup));
40553f8f7c5SWolfram Sang 	lookup.info = info;
40653f8f7c5SWolfram Sang 	lookup.device_handle = acpi_device_handle(adev);
40753f8f7c5SWolfram Sang 	lookup.index = index;
40853f8f7c5SWolfram Sang 
40953f8f7c5SWolfram Sang 	ret = acpi_dev_get_resources(adev, &resource_list,
41053f8f7c5SWolfram Sang 				     i2c_acpi_fill_info, &lookup);
41153f8f7c5SWolfram Sang 	acpi_dev_free_resource_list(&resource_list);
41253f8f7c5SWolfram Sang 
41353f8f7c5SWolfram Sang 	if (ret < 0 || !info->addr)
41453f8f7c5SWolfram Sang 		return NULL;
41553f8f7c5SWolfram Sang 
41653f8f7c5SWolfram Sang 	adapter = i2c_acpi_find_adapter_by_handle(lookup.adapter_handle);
41753f8f7c5SWolfram Sang 	if (!adapter)
41853f8f7c5SWolfram Sang 		return NULL;
41953f8f7c5SWolfram Sang 
42053f8f7c5SWolfram Sang 	return i2c_new_device(adapter, info);
42153f8f7c5SWolfram Sang }
42253f8f7c5SWolfram Sang EXPORT_SYMBOL_GPL(i2c_acpi_new_device);
42353f8f7c5SWolfram Sang 
42453f8f7c5SWolfram Sang #ifdef CONFIG_ACPI_I2C_OPREGION
42553f8f7c5SWolfram Sang static int acpi_gsb_i2c_read_bytes(struct i2c_client *client,
42653f8f7c5SWolfram Sang 		u8 cmd, u8 *data, u8 data_len)
42753f8f7c5SWolfram Sang {
42853f8f7c5SWolfram Sang 
42953f8f7c5SWolfram Sang 	struct i2c_msg msgs[2];
43053f8f7c5SWolfram Sang 	int ret;
43153f8f7c5SWolfram Sang 	u8 *buffer;
43253f8f7c5SWolfram Sang 
43353f8f7c5SWolfram Sang 	buffer = kzalloc(data_len, GFP_KERNEL);
43453f8f7c5SWolfram Sang 	if (!buffer)
43553f8f7c5SWolfram Sang 		return AE_NO_MEMORY;
43653f8f7c5SWolfram Sang 
43753f8f7c5SWolfram Sang 	msgs[0].addr = client->addr;
43853f8f7c5SWolfram Sang 	msgs[0].flags = client->flags;
43953f8f7c5SWolfram Sang 	msgs[0].len = 1;
44053f8f7c5SWolfram Sang 	msgs[0].buf = &cmd;
44153f8f7c5SWolfram Sang 
44253f8f7c5SWolfram Sang 	msgs[1].addr = client->addr;
44353f8f7c5SWolfram Sang 	msgs[1].flags = client->flags | I2C_M_RD;
44453f8f7c5SWolfram Sang 	msgs[1].len = data_len;
44553f8f7c5SWolfram Sang 	msgs[1].buf = buffer;
44653f8f7c5SWolfram Sang 
44753f8f7c5SWolfram Sang 	ret = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs));
44853f8f7c5SWolfram Sang 	if (ret < 0)
44953f8f7c5SWolfram Sang 		dev_err(&client->adapter->dev, "i2c read failed\n");
45053f8f7c5SWolfram Sang 	else
45153f8f7c5SWolfram Sang 		memcpy(data, buffer, data_len);
45253f8f7c5SWolfram Sang 
45353f8f7c5SWolfram Sang 	kfree(buffer);
45453f8f7c5SWolfram Sang 	return ret;
45553f8f7c5SWolfram Sang }
45653f8f7c5SWolfram Sang 
45753f8f7c5SWolfram Sang static int acpi_gsb_i2c_write_bytes(struct i2c_client *client,
45853f8f7c5SWolfram Sang 		u8 cmd, u8 *data, u8 data_len)
45953f8f7c5SWolfram Sang {
46053f8f7c5SWolfram Sang 
46153f8f7c5SWolfram Sang 	struct i2c_msg msgs[1];
46253f8f7c5SWolfram Sang 	u8 *buffer;
46353f8f7c5SWolfram Sang 	int ret = AE_OK;
46453f8f7c5SWolfram Sang 
46553f8f7c5SWolfram Sang 	buffer = kzalloc(data_len + 1, GFP_KERNEL);
46653f8f7c5SWolfram Sang 	if (!buffer)
46753f8f7c5SWolfram Sang 		return AE_NO_MEMORY;
46853f8f7c5SWolfram Sang 
46953f8f7c5SWolfram Sang 	buffer[0] = cmd;
47053f8f7c5SWolfram Sang 	memcpy(buffer + 1, data, data_len);
47153f8f7c5SWolfram Sang 
47253f8f7c5SWolfram Sang 	msgs[0].addr = client->addr;
47353f8f7c5SWolfram Sang 	msgs[0].flags = client->flags;
47453f8f7c5SWolfram Sang 	msgs[0].len = data_len + 1;
47553f8f7c5SWolfram Sang 	msgs[0].buf = buffer;
47653f8f7c5SWolfram Sang 
47753f8f7c5SWolfram Sang 	ret = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs));
47853f8f7c5SWolfram Sang 	if (ret < 0)
47953f8f7c5SWolfram Sang 		dev_err(&client->adapter->dev, "i2c write failed\n");
48053f8f7c5SWolfram Sang 
48153f8f7c5SWolfram Sang 	kfree(buffer);
48253f8f7c5SWolfram Sang 	return ret;
48353f8f7c5SWolfram Sang }
48453f8f7c5SWolfram Sang 
48553f8f7c5SWolfram Sang static acpi_status
48653f8f7c5SWolfram Sang i2c_acpi_space_handler(u32 function, acpi_physical_address command,
48753f8f7c5SWolfram Sang 			u32 bits, u64 *value64,
48853f8f7c5SWolfram Sang 			void *handler_context, void *region_context)
48953f8f7c5SWolfram Sang {
49053f8f7c5SWolfram Sang 	struct gsb_buffer *gsb = (struct gsb_buffer *)value64;
49153f8f7c5SWolfram Sang 	struct i2c_acpi_handler_data *data = handler_context;
49253f8f7c5SWolfram Sang 	struct acpi_connection_info *info = &data->info;
49353f8f7c5SWolfram Sang 	struct acpi_resource_i2c_serialbus *sb;
49453f8f7c5SWolfram Sang 	struct i2c_adapter *adapter = data->adapter;
49553f8f7c5SWolfram Sang 	struct i2c_client *client;
49653f8f7c5SWolfram Sang 	struct acpi_resource *ares;
49753f8f7c5SWolfram Sang 	u32 accessor_type = function >> 16;
49853f8f7c5SWolfram Sang 	u8 action = function & ACPI_IO_MASK;
49953f8f7c5SWolfram Sang 	acpi_status ret;
50053f8f7c5SWolfram Sang 	int status;
50153f8f7c5SWolfram Sang 
50253f8f7c5SWolfram Sang 	ret = acpi_buffer_to_resource(info->connection, info->length, &ares);
50353f8f7c5SWolfram Sang 	if (ACPI_FAILURE(ret))
50453f8f7c5SWolfram Sang 		return ret;
50553f8f7c5SWolfram Sang 
50653f8f7c5SWolfram Sang 	client = kzalloc(sizeof(*client), GFP_KERNEL);
50753f8f7c5SWolfram Sang 	if (!client) {
50853f8f7c5SWolfram Sang 		ret = AE_NO_MEMORY;
50953f8f7c5SWolfram Sang 		goto err;
51053f8f7c5SWolfram Sang 	}
51153f8f7c5SWolfram Sang 
51253f8f7c5SWolfram Sang 	if (!value64 || ares->type != ACPI_RESOURCE_TYPE_SERIAL_BUS) {
51353f8f7c5SWolfram Sang 		ret = AE_BAD_PARAMETER;
51453f8f7c5SWolfram Sang 		goto err;
51553f8f7c5SWolfram Sang 	}
51653f8f7c5SWolfram Sang 
51753f8f7c5SWolfram Sang 	sb = &ares->data.i2c_serial_bus;
51853f8f7c5SWolfram Sang 	if (sb->type != ACPI_RESOURCE_SERIAL_TYPE_I2C) {
51953f8f7c5SWolfram Sang 		ret = AE_BAD_PARAMETER;
52053f8f7c5SWolfram Sang 		goto err;
52153f8f7c5SWolfram Sang 	}
52253f8f7c5SWolfram Sang 
52353f8f7c5SWolfram Sang 	client->adapter = adapter;
52453f8f7c5SWolfram Sang 	client->addr = sb->slave_address;
52553f8f7c5SWolfram Sang 
52653f8f7c5SWolfram Sang 	if (sb->access_mode == ACPI_I2C_10BIT_MODE)
52753f8f7c5SWolfram Sang 		client->flags |= I2C_CLIENT_TEN;
52853f8f7c5SWolfram Sang 
52953f8f7c5SWolfram Sang 	switch (accessor_type) {
53053f8f7c5SWolfram Sang 	case ACPI_GSB_ACCESS_ATTRIB_SEND_RCV:
53153f8f7c5SWolfram Sang 		if (action == ACPI_READ) {
53253f8f7c5SWolfram Sang 			status = i2c_smbus_read_byte(client);
53353f8f7c5SWolfram Sang 			if (status >= 0) {
53453f8f7c5SWolfram Sang 				gsb->bdata = status;
53553f8f7c5SWolfram Sang 				status = 0;
53653f8f7c5SWolfram Sang 			}
53753f8f7c5SWolfram Sang 		} else {
53853f8f7c5SWolfram Sang 			status = i2c_smbus_write_byte(client, gsb->bdata);
53953f8f7c5SWolfram Sang 		}
54053f8f7c5SWolfram Sang 		break;
54153f8f7c5SWolfram Sang 
54253f8f7c5SWolfram Sang 	case ACPI_GSB_ACCESS_ATTRIB_BYTE:
54353f8f7c5SWolfram Sang 		if (action == ACPI_READ) {
54453f8f7c5SWolfram Sang 			status = i2c_smbus_read_byte_data(client, command);
54553f8f7c5SWolfram Sang 			if (status >= 0) {
54653f8f7c5SWolfram Sang 				gsb->bdata = status;
54753f8f7c5SWolfram Sang 				status = 0;
54853f8f7c5SWolfram Sang 			}
54953f8f7c5SWolfram Sang 		} else {
55053f8f7c5SWolfram Sang 			status = i2c_smbus_write_byte_data(client, command,
55153f8f7c5SWolfram Sang 					gsb->bdata);
55253f8f7c5SWolfram Sang 		}
55353f8f7c5SWolfram Sang 		break;
55453f8f7c5SWolfram Sang 
55553f8f7c5SWolfram Sang 	case ACPI_GSB_ACCESS_ATTRIB_WORD:
55653f8f7c5SWolfram Sang 		if (action == ACPI_READ) {
55753f8f7c5SWolfram Sang 			status = i2c_smbus_read_word_data(client, command);
55853f8f7c5SWolfram Sang 			if (status >= 0) {
55953f8f7c5SWolfram Sang 				gsb->wdata = status;
56053f8f7c5SWolfram Sang 				status = 0;
56153f8f7c5SWolfram Sang 			}
56253f8f7c5SWolfram Sang 		} else {
56353f8f7c5SWolfram Sang 			status = i2c_smbus_write_word_data(client, command,
56453f8f7c5SWolfram Sang 					gsb->wdata);
56553f8f7c5SWolfram Sang 		}
56653f8f7c5SWolfram Sang 		break;
56753f8f7c5SWolfram Sang 
56853f8f7c5SWolfram Sang 	case ACPI_GSB_ACCESS_ATTRIB_BLOCK:
56953f8f7c5SWolfram Sang 		if (action == ACPI_READ) {
57053f8f7c5SWolfram Sang 			status = i2c_smbus_read_block_data(client, command,
57153f8f7c5SWolfram Sang 					gsb->data);
57253f8f7c5SWolfram Sang 			if (status >= 0) {
57353f8f7c5SWolfram Sang 				gsb->len = status;
57453f8f7c5SWolfram Sang 				status = 0;
57553f8f7c5SWolfram Sang 			}
57653f8f7c5SWolfram Sang 		} else {
57753f8f7c5SWolfram Sang 			status = i2c_smbus_write_block_data(client, command,
57853f8f7c5SWolfram Sang 					gsb->len, gsb->data);
57953f8f7c5SWolfram Sang 		}
58053f8f7c5SWolfram Sang 		break;
58153f8f7c5SWolfram Sang 
58253f8f7c5SWolfram Sang 	case ACPI_GSB_ACCESS_ATTRIB_MULTIBYTE:
58353f8f7c5SWolfram Sang 		if (action == ACPI_READ) {
58453f8f7c5SWolfram Sang 			status = acpi_gsb_i2c_read_bytes(client, command,
58553f8f7c5SWolfram Sang 					gsb->data, info->access_length);
58653f8f7c5SWolfram Sang 			if (status > 0)
58753f8f7c5SWolfram Sang 				status = 0;
58853f8f7c5SWolfram Sang 		} else {
58953f8f7c5SWolfram Sang 			status = acpi_gsb_i2c_write_bytes(client, command,
59053f8f7c5SWolfram Sang 					gsb->data, info->access_length);
59153f8f7c5SWolfram Sang 		}
59253f8f7c5SWolfram Sang 		break;
59353f8f7c5SWolfram Sang 
59453f8f7c5SWolfram Sang 	default:
59553f8f7c5SWolfram Sang 		dev_warn(&adapter->dev, "protocol 0x%02x not supported for client 0x%02x\n",
59653f8f7c5SWolfram Sang 			 accessor_type, client->addr);
59753f8f7c5SWolfram Sang 		ret = AE_BAD_PARAMETER;
59853f8f7c5SWolfram Sang 		goto err;
59953f8f7c5SWolfram Sang 	}
60053f8f7c5SWolfram Sang 
60153f8f7c5SWolfram Sang 	gsb->status = status;
60253f8f7c5SWolfram Sang 
60353f8f7c5SWolfram Sang  err:
60453f8f7c5SWolfram Sang 	kfree(client);
60553f8f7c5SWolfram Sang 	ACPI_FREE(ares);
60653f8f7c5SWolfram Sang 	return ret;
60753f8f7c5SWolfram Sang }
60853f8f7c5SWolfram Sang 
60953f8f7c5SWolfram Sang 
61053f8f7c5SWolfram Sang int i2c_acpi_install_space_handler(struct i2c_adapter *adapter)
61153f8f7c5SWolfram Sang {
61253f8f7c5SWolfram Sang 	acpi_handle handle;
61353f8f7c5SWolfram Sang 	struct i2c_acpi_handler_data *data;
61453f8f7c5SWolfram Sang 	acpi_status status;
61553f8f7c5SWolfram Sang 
61653f8f7c5SWolfram Sang 	if (!adapter->dev.parent)
61753f8f7c5SWolfram Sang 		return -ENODEV;
61853f8f7c5SWolfram Sang 
61953f8f7c5SWolfram Sang 	handle = ACPI_HANDLE(adapter->dev.parent);
62053f8f7c5SWolfram Sang 
62153f8f7c5SWolfram Sang 	if (!handle)
62253f8f7c5SWolfram Sang 		return -ENODEV;
62353f8f7c5SWolfram Sang 
62453f8f7c5SWolfram Sang 	data = kzalloc(sizeof(struct i2c_acpi_handler_data),
62553f8f7c5SWolfram Sang 			    GFP_KERNEL);
62653f8f7c5SWolfram Sang 	if (!data)
62753f8f7c5SWolfram Sang 		return -ENOMEM;
62853f8f7c5SWolfram Sang 
62953f8f7c5SWolfram Sang 	data->adapter = adapter;
63053f8f7c5SWolfram Sang 	status = acpi_bus_attach_private_data(handle, (void *)data);
63153f8f7c5SWolfram Sang 	if (ACPI_FAILURE(status)) {
63253f8f7c5SWolfram Sang 		kfree(data);
63353f8f7c5SWolfram Sang 		return -ENOMEM;
63453f8f7c5SWolfram Sang 	}
63553f8f7c5SWolfram Sang 
63653f8f7c5SWolfram Sang 	status = acpi_install_address_space_handler(handle,
63753f8f7c5SWolfram Sang 				ACPI_ADR_SPACE_GSBUS,
63853f8f7c5SWolfram Sang 				&i2c_acpi_space_handler,
63953f8f7c5SWolfram Sang 				NULL,
64053f8f7c5SWolfram Sang 				data);
64153f8f7c5SWolfram Sang 	if (ACPI_FAILURE(status)) {
64253f8f7c5SWolfram Sang 		dev_err(&adapter->dev, "Error installing i2c space handler\n");
64353f8f7c5SWolfram Sang 		acpi_bus_detach_private_data(handle);
64453f8f7c5SWolfram Sang 		kfree(data);
64553f8f7c5SWolfram Sang 		return -ENOMEM;
64653f8f7c5SWolfram Sang 	}
64753f8f7c5SWolfram Sang 
64853f8f7c5SWolfram Sang 	acpi_walk_dep_device_list(handle);
64953f8f7c5SWolfram Sang 	return 0;
65053f8f7c5SWolfram Sang }
65153f8f7c5SWolfram Sang 
65253f8f7c5SWolfram Sang void i2c_acpi_remove_space_handler(struct i2c_adapter *adapter)
65353f8f7c5SWolfram Sang {
65453f8f7c5SWolfram Sang 	acpi_handle handle;
65553f8f7c5SWolfram Sang 	struct i2c_acpi_handler_data *data;
65653f8f7c5SWolfram Sang 	acpi_status status;
65753f8f7c5SWolfram Sang 
65853f8f7c5SWolfram Sang 	if (!adapter->dev.parent)
65953f8f7c5SWolfram Sang 		return;
66053f8f7c5SWolfram Sang 
66153f8f7c5SWolfram Sang 	handle = ACPI_HANDLE(adapter->dev.parent);
66253f8f7c5SWolfram Sang 
66353f8f7c5SWolfram Sang 	if (!handle)
66453f8f7c5SWolfram Sang 		return;
66553f8f7c5SWolfram Sang 
66653f8f7c5SWolfram Sang 	acpi_remove_address_space_handler(handle,
66753f8f7c5SWolfram Sang 				ACPI_ADR_SPACE_GSBUS,
66853f8f7c5SWolfram Sang 				&i2c_acpi_space_handler);
66953f8f7c5SWolfram Sang 
67053f8f7c5SWolfram Sang 	status = acpi_bus_get_private_data(handle, (void **)&data);
67153f8f7c5SWolfram Sang 	if (ACPI_SUCCESS(status))
67253f8f7c5SWolfram Sang 		kfree(data);
67353f8f7c5SWolfram Sang 
67453f8f7c5SWolfram Sang 	acpi_bus_detach_private_data(handle);
67553f8f7c5SWolfram Sang }
67653f8f7c5SWolfram Sang #endif /* CONFIG_ACPI_I2C_OPREGION */
677