[deliverable/linux.git] / drivers / i2c / i2c-acpi.c

/*
 * I2C ACPI code
 *
 * Copyright (C) 2014 Intel Corp
 *
 * Author: Lan Tianyu <tianyu.lan@intel.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
 * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * for more details.
 */
#define pr_fmt(fmt) "I2C/ACPI : " fmt

#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/err.h>
#include <linux/i2c.h>
#include <linux/acpi.h>

struct acpi_i2c_handler_data {
	struct acpi_connection_info info;
	struct i2c_adapter *adapter;
};

struct gsb_buffer {
	u8	status;
	u8	len;
	union {
		u16	wdata;
		u8	bdata;
		u8	data[0];
	};
} __packed;

static int acpi_i2c_add_resource(struct acpi_resource *ares, void *data)
{
	struct i2c_board_info *info = data;

	if (ares->type == ACPI_RESOURCE_TYPE_SERIAL_BUS) {
		struct acpi_resource_i2c_serialbus *sb;

		sb = &ares->data.i2c_serial_bus;
		if (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 < 0) {
		struct resource r;

		if (acpi_dev_resource_interrupt(ares, 0, &r))
			info->irq = r.start;
	}

	/* Tell the ACPI core to skip this resource */
	return 1;
}

static acpi_status acpi_i2c_add_device(acpi_handle handle, u32 level,
				       void *data, void **return_value)
{
	struct i2c_adapter *adapter = data;
	struct list_head resource_list;
	struct i2c_board_info info;
	struct acpi_device *adev;
	int ret;

	if (acpi_bus_get_device(handle, &adev))
		return AE_OK;
	if (acpi_bus_get_status(adev) || !adev->status.present)
		return AE_OK;

	memset(&info, 0, sizeof(info));
	info.acpi_node.companion = adev;
	info.irq = -1;

	INIT_LIST_HEAD(&resource_list);
	ret = acpi_dev_get_resources(adev, &resource_list,
				     acpi_i2c_add_resource, &info);
	acpi_dev_free_resource_list(&resource_list);

	if (ret < 0 || !info.addr)
		return AE_OK;

	adev->power.flags.ignore_parent = true;
	strlcpy(info.type, dev_name(&adev->dev), sizeof(info.type));
	if (!i2c_new_device(adapter, &info)) {
		adev->power.flags.ignore_parent = false;
		dev_err(&adapter->dev,
			"failed to add I2C device %s from ACPI\n",
			dev_name(&adev->dev));
	}

	return AE_OK;
}

/**
 * acpi_i2c_register_devices - enumerate I2C slave devices behind adapter
 * @adap: pointer to adapter
 *
 * Enumerate all I2C slave devices behind this adapter by walking the ACPI
 * namespace. When a device is found it will be added to the Linux device
 * model and bound to the corresponding ACPI handle.
 */
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)
		return;

	status = acpi_walk_namespace(ACPI_TYPE_DEVICE, handle, 1,
				     acpi_i2c_add_device, NULL,
				     adap, NULL);
	if (ACPI_FAILURE(status))
		dev_warn(&adap->dev, "failed to enumerate I2C slaves\n");
}

static int acpi_gsb_i2c_read_bytes(struct i2c_client *client,
		u8 cmd, u8 *data, u8 data_len)
{

	struct i2c_msg msgs[2];
	int ret;
	u8 *buffer;

	buffer = kzalloc(data_len, GFP_KERNEL);
	if (!buffer)
		return AE_NO_MEMORY;

	msgs[0].addr = client->addr;
	msgs[0].flags = client->flags;
	msgs[0].len = 1;
	msgs[0].buf = &cmd;

	msgs[1].addr = client->addr;
	msgs[1].flags = client->flags | I2C_M_RD;
	msgs[1].len = data_len;
	msgs[1].buf = buffer;

	ret = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs));
	if (ret < 0)
		dev_err(&client->adapter->dev, "i2c read failed\n");
	else
		memcpy(data, buffer, data_len);

	kfree(buffer);
	return ret;
}

static int acpi_gsb_i2c_write_bytes(struct i2c_client *client,
		u8 cmd, u8 *data, u8 data_len)
{

	struct i2c_msg msgs[1];
	u8 *buffer;
	int ret = AE_OK;

	buffer = kzalloc(data_len + 1, GFP_KERNEL);
	if (!buffer)
		return AE_NO_MEMORY;

	buffer[0] = cmd;
	memcpy(buffer + 1, data, data_len);

	msgs[0].addr = client->addr;
	msgs[0].flags = client->flags;
	msgs[0].len = data_len + 1;
	msgs[0].buf = buffer;

	ret = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs));
	if (ret < 0)
		dev_err(&client->adapter->dev, "i2c write failed\n");

	kfree(buffer);
	return ret;
}

static acpi_status
acpi_i2c_space_handler(u32 function, acpi_physical_address command,
			u32 bits, u64 *value64,
			void *handler_context, void *region_context)
{
	struct gsb_buffer *gsb = (struct gsb_buffer *)value64;
	struct acpi_i2c_handler_data *data = handler_context;
	struct acpi_connection_info *info = &data->info;
	struct acpi_resource_i2c_serialbus *sb;
	struct i2c_adapter *adapter = data->adapter;
	struct i2c_client client;
	struct acpi_resource *ares;
	u32 accessor_type = function >> 16;
	u8 action = function & ACPI_IO_MASK;
	acpi_status ret = AE_OK;
	int status;

	ret = acpi_buffer_to_resource(info->connection, info->length, &ares);
	if (ACPI_FAILURE(ret))
		return ret;

	if (!value64 || ares->type != ACPI_RESOURCE_TYPE_SERIAL_BUS) {
		ret = AE_BAD_PARAMETER;
		goto err;
	}

	sb = &ares->data.i2c_serial_bus;
	if (sb->type != ACPI_RESOURCE_SERIAL_TYPE_I2C) {
		ret = AE_BAD_PARAMETER;
		goto err;
	}

	memset(&client, 0, sizeof(client));
	client.adapter = adapter;
	client.addr = sb->slave_address;
	client.flags = 0;

	if (sb->access_mode == ACPI_I2C_10BIT_MODE)
		client.flags |= I2C_CLIENT_TEN;

	switch (accessor_type) {
	case ACPI_GSB_ACCESS_ATTRIB_SEND_RCV:
		if (action == ACPI_READ) {
			status = i2c_smbus_read_byte(&client);
			if (status >= 0) {
				gsb->bdata = status;
				status = 0;
			}
		} else {
			status = i2c_smbus_write_byte(&client, gsb->bdata);
		}
		break;

	case ACPI_GSB_ACCESS_ATTRIB_BYTE:
		if (action == ACPI_READ) {
			status = i2c_smbus_read_byte_data(&client, command);
			if (status >= 0) {
				gsb->bdata = status;
				status = 0;
			}
		} else {
			status = i2c_smbus_write_byte_data(&client, command,
					gsb->bdata);
		}
		break;

	case ACPI_GSB_ACCESS_ATTRIB_WORD:
		if (action == ACPI_READ) {
			status = i2c_smbus_read_word_data(&client, command);
			if (status >= 0) {
				gsb->wdata = status;
				status = 0;
			}
		} else {
			status = i2c_smbus_write_word_data(&client, command,
					gsb->wdata);
		}
		break;

	case ACPI_GSB_ACCESS_ATTRIB_BLOCK:
		if (action == ACPI_READ) {
			status = i2c_smbus_read_block_data(&client, command,
					gsb->data);
			if (status >= 0) {
				gsb->len = status;
				status = 0;
			}
		} else {
			status = i2c_smbus_write_block_data(&client, command,
					gsb->len, gsb->data);
		}
		break;

	case ACPI_GSB_ACCESS_ATTRIB_MULTIBYTE:
		if (action == ACPI_READ) {
			status = acpi_gsb_i2c_read_bytes(&client, command,
					gsb->data, info->access_length);
			if (status > 0)
				status = 0;
		} else {
			status = acpi_gsb_i2c_write_bytes(&client, command,
					gsb->data, info->access_length);
		}
		break;

	default:
		pr_info("protocol(0x%02x) is not supported.\n", accessor_type);
		ret = AE_BAD_PARAMETER;
		goto err;
	}

	gsb->status = status;

 err:
	ACPI_FREE(ares);
	return ret;
}


int acpi_i2c_install_space_handler(struct i2c_adapter *adapter)
{
	acpi_handle handle = ACPI_HANDLE(adapter->dev.parent);
	struct acpi_i2c_handler_data *data;
	acpi_status status;

	if (!handle)
		return -ENODEV;

	data = kzalloc(sizeof(struct acpi_i2c_handler_data),
			    GFP_KERNEL);
	if (!data)
		return -ENOMEM;

	data->adapter = adapter;
	status = acpi_bus_attach_private_data(handle, (void *)data);
	if (ACPI_FAILURE(status)) {
		kfree(data);
		return -ENOMEM;
	}

	status = acpi_install_address_space_handler(handle,
				ACPI_ADR_SPACE_GSBUS,
				&acpi_i2c_space_handler,
				NULL,
				data);
	if (ACPI_FAILURE(status)) {
		dev_err(&adapter->dev, "Error installing i2c space handler\n");
		acpi_bus_detach_private_data(handle);
		kfree(data);
		return -ENOMEM;
	}

	return 0;
}

void acpi_i2c_remove_space_handler(struct i2c_adapter *adapter)
{
	acpi_handle handle = ACPI_HANDLE(adapter->dev.parent);
	struct acpi_i2c_handler_data *data;
	acpi_status status;

	if (!handle)
		return;

	acpi_remove_address_space_handler(handle,
				ACPI_ADR_SPACE_GSBUS,
				&acpi_i2c_space_handler);

	status = acpi_bus_get_private_data(handle, (void **)&data);
	if (ACPI_SUCCESS(status))
		kfree(data);

	acpi_bus_detach_private_data(handle);
}
Commit	Line	Data
5d98e61d LT	1	/*
	2	* I2C ACPI code
	3	*
	4	* Copyright (C) 2014 Intel Corp
	5	*
	6	* Author: Lan Tianyu <tianyu.lan@intel.com>
	7	*
	8	* This program is free software; you can redistribute it and/or modify
	9	* it under the terms of the GNU General Public License version 2 as
	10	* published by the Free Software Foundation.
	11	*
	12	* This program is distributed in the hope that it will be useful, but
	13	* WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
	14	* or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
	15	* for more details.
	16	*/
	17	#define pr_fmt(fmt) "I2C/ACPI : " fmt
	18
	19	#include <linux/kernel.h>
	20	#include <linux/errno.h>
	21	#include <linux/err.h>
	22	#include <linux/i2c.h>
	23	#include <linux/acpi.h>
	24
	25	struct acpi_i2c_handler_data {
	26	struct acpi_connection_info info;
	27	struct i2c_adapter *adapter;
	28	};
	29
	30	struct gsb_buffer {
	31	u8 status;
	32	u8 len;
	33	union {
	34	u16 wdata;
	35	u8 bdata;
	36	u8 data[0];
	37	};
	38	} __packed;
	39
da3c6647 LT	40	static int acpi_i2c_add_resource(struct acpi_resource ares, void data)
	41	{
	42	struct i2c_board_info *info = data;
	43
	44	if (ares->type == ACPI_RESOURCE_TYPE_SERIAL_BUS) {
	45	struct acpi_resource_i2c_serialbus *sb;
	46
	47	sb = &ares->data.i2c_serial_bus;
	48	if (sb->type == ACPI_RESOURCE_SERIAL_TYPE_I2C) {
	49	info->addr = sb->slave_address;
	50	if (sb->access_mode == ACPI_I2C_10BIT_MODE)
	51	info->flags \|= I2C_CLIENT_TEN;
	52	}
	53	} else if (info->irq < 0) {
	54	struct resource r;
	55
	56	if (acpi_dev_resource_interrupt(ares, 0, &r))
	57	info->irq = r.start;
	58	}
	59
	60	/* Tell the ACPI core to skip this resource */
	61	return 1;
	62	}
	63
	64	static acpi_status acpi_i2c_add_device(acpi_handle handle, u32 level,
	65	void data, void *return_value)
	66	{
	67	struct i2c_adapter *adapter = data;
	68	struct list_head resource_list;
	69	struct i2c_board_info info;
	70	struct acpi_device *adev;
	71	int ret;
	72
	73	if (acpi_bus_get_device(handle, &adev))
	74	return AE_OK;
	75	if (acpi_bus_get_status(adev) \|\| !adev->status.present)
	76	return AE_OK;
	77
	78	memset(&info, 0, sizeof(info));
	79	info.acpi_node.companion = adev;
	80	info.irq = -1;
	81
	82	INIT_LIST_HEAD(&resource_list);
	83	ret = acpi_dev_get_resources(adev, &resource_list,
	84	acpi_i2c_add_resource, &info);
	85	acpi_dev_free_resource_list(&resource_list);
	86
	87	if (ret < 0 \|\| !info.addr)
	88	return AE_OK;
	89
	90	adev->power.flags.ignore_parent = true;
	91	strlcpy(info.type, dev_name(&adev->dev), sizeof(info.type));
	92	if (!i2c_new_device(adapter, &info)) {
	93	adev->power.flags.ignore_parent = false;
	94	dev_err(&adapter->dev,
	95	"failed to add I2C device %s from ACPI\n",
	96	dev_name(&adev->dev));
	97	}
	98
	99	return AE_OK;
	100	}
	101
	102	/**
	103	* acpi_i2c_register_devices - enumerate I2C slave devices behind adapter
104	* @adap: pointer to adapter
105	*
106	* Enumerate all I2C slave devices behind this adapter by walking the ACPI
107	* namespace. When a device is found it will be added to the Linux device
108	* model and bound to the corresponding ACPI handle.
109	*/
110	void acpi_i2c_register_devices(struct i2c_adapter *adap)
111	{
112	acpi_handle handle;
113	acpi_status status;
114
115	if (!adap->dev.parent)
116	return;
117
118	handle = ACPI_HANDLE(adap->dev.parent);
119	if (!handle)
120	return;
121
122	status = acpi_walk_namespace(ACPI_TYPE_DEVICE, handle, 1,
123	acpi_i2c_add_device, NULL,
124	adap, NULL);
125	if (ACPI_FAILURE(status))
126	dev_warn(&adap->dev, "failed to enumerate I2C slaves\n");
127	}
128
5d98e61d LT	129	static int acpi_gsb_i2c_read_bytes(struct i2c_client *client,
	130	u8 cmd, u8 *data, u8 data_len)
	131	{
	132
	133	struct i2c_msg msgs[2];
	134	int ret;
	135	u8 *buffer;
	136
	137	buffer = kzalloc(data_len, GFP_KERNEL);
	138	if (!buffer)
	139	return AE_NO_MEMORY;
	140
	141	msgs[0].addr = client->addr;
	142	msgs[0].flags = client->flags;
	143	msgs[0].len = 1;
	144	msgs[0].buf = &cmd;
	145
	146	msgs[1].addr = client->addr;
	147	msgs[1].flags = client->flags \| I2C_M_RD;
	148	msgs[1].len = data_len;
	149	msgs[1].buf = buffer;
	150
	151	ret = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs));
	152	if (ret < 0)
	153	dev_err(&client->adapter->dev, "i2c read failed\n");
	154	else
	155	memcpy(data, buffer, data_len);
	156
	157	kfree(buffer);
	158	return ret;
	159	}
	160
	161	static int acpi_gsb_i2c_write_bytes(struct i2c_client *client,
	162	u8 cmd, u8 *data, u8 data_len)
	163	{
	164
	165	struct i2c_msg msgs[1];
	166	u8 *buffer;
	167	int ret = AE_OK;
	168
	169	buffer = kzalloc(data_len + 1, GFP_KERNEL);
	170	if (!buffer)
	171	return AE_NO_MEMORY;
	172
	173	buffer[0] = cmd;
	174	memcpy(buffer + 1, data, data_len);
	175
	176	msgs[0].addr = client->addr;
	177	msgs[0].flags = client->flags;
	178	msgs[0].len = data_len + 1;
	179	msgs[0].buf = buffer;
	180
	181	ret = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs));
	182	if (ret < 0)
	183	dev_err(&client->adapter->dev, "i2c write failed\n");
	184
	185	kfree(buffer);
	186	return ret;
	187	}
	188
	189	static acpi_status
	190	acpi_i2c_space_handler(u32 function, acpi_physical_address command,
	191	u32 bits, u64 *value64,
	192	void handler_context, void region_context)
193	{
194	struct gsb_buffer gsb = (struct gsb_buffer )value64;
195	struct acpi_i2c_handler_data *data = handler_context;
196	struct acpi_connection_info *info = &data->info;
197	struct acpi_resource_i2c_serialbus *sb;
198	struct i2c_adapter *adapter = data->adapter;
199	struct i2c_client client;
200	struct acpi_resource *ares;
201	u32 accessor_type = function >> 16;
202	u8 action = function & ACPI_IO_MASK;
203	acpi_status ret = AE_OK;
204	int status;
205
206	ret = acpi_buffer_to_resource(info->connection, info->length, &ares);
207	if (ACPI_FAILURE(ret))
208	return ret;
209
210	if (!value64 \|\| ares->type != ACPI_RESOURCE_TYPE_SERIAL_BUS) {
211	ret = AE_BAD_PARAMETER;
212	goto err;
213	}
214
215	sb = &ares->data.i2c_serial_bus;
216	if (sb->type != ACPI_RESOURCE_SERIAL_TYPE_I2C) {
217	ret = AE_BAD_PARAMETER;
218	goto err;
219	}
220
221	memset(&client, 0, sizeof(client));
222	client.adapter = adapter;
223	client.addr = sb->slave_address;
224	client.flags = 0;
225
226	if (sb->access_mode == ACPI_I2C_10BIT_MODE)
227	client.flags \|= I2C_CLIENT_TEN;
228
229	switch (accessor_type) {
230	case ACPI_GSB_ACCESS_ATTRIB_SEND_RCV:
231	if (action == ACPI_READ) {
232	status = i2c_smbus_read_byte(&client);
233	if (status >= 0) {
234	gsb->bdata = status;
235	status = 0;
236	}
237	} else {
238	status = i2c_smbus_write_byte(&client, gsb->bdata);
239	}
240	break;
241
242	case ACPI_GSB_ACCESS_ATTRIB_BYTE:
243	if (action == ACPI_READ) {
244	status = i2c_smbus_read_byte_data(&client, command);
245	if (status >= 0) {
246	gsb->bdata = status;
247	status = 0;
248	}
249	} else {
250	status = i2c_smbus_write_byte_data(&client, command,
251	gsb->bdata);
252	}
253	break;
254
255	case ACPI_GSB_ACCESS_ATTRIB_WORD:
256	if (action == ACPI_READ) {
257	status = i2c_smbus_read_word_data(&client, command);
258	if (status >= 0) {
259	gsb->wdata = status;
260	status = 0;
261	}
262	} else {
263	status = i2c_smbus_write_word_data(&client, command,
264	gsb->wdata);
265	}
266	break;
267
268	case ACPI_GSB_ACCESS_ATTRIB_BLOCK:
269	if (action == ACPI_READ) {
270	status = i2c_smbus_read_block_data(&client, command,
271	gsb->data);
272	if (status >= 0) {
273	gsb->len = status;
274	status = 0;
275	}
276	} else {
277	status = i2c_smbus_write_block_data(&client, command,
278	gsb->len, gsb->data);
279	}
280	break;
281
282	case ACPI_GSB_ACCESS_ATTRIB_MULTIBYTE:
283	if (action == ACPI_READ) {
284	status = acpi_gsb_i2c_read_bytes(&client, command,
285	gsb->data, info->access_length);
286	if (status > 0)
287	status = 0;
288	} else {
289	status = acpi_gsb_i2c_write_bytes(&client, command,
290	gsb->data, info->access_length);
291	}
292	break;
293
294	default:
295	pr_info("protocol(0x%02x) is not supported.\n", accessor_type);
296	ret = AE_BAD_PARAMETER;
297	goto err;
298	}
299
300	gsb->status = status;
301
302	err:
303	ACPI_FREE(ares);
304	return ret;
305	}
306
307
308	int acpi_i2c_install_space_handler(struct i2c_adapter *adapter)
309	{
310	acpi_handle handle = ACPI_HANDLE(adapter->dev.parent);
311	struct acpi_i2c_handler_data *data;
312	acpi_status status;
313
314	if (!handle)
315	return -ENODEV;
316
317	data = kzalloc(sizeof(struct acpi_i2c_handler_data),
318	GFP_KERNEL);
319	if (!data)
320	return -ENOMEM;
321
322	data->adapter = adapter;
323	status = acpi_bus_attach_private_data(handle, (void *)data);
324	if (ACPI_FAILURE(status)) {
325	kfree(data);
326	return -ENOMEM;
327	}
328
329	status = acpi_install_address_space_handler(handle,
330	ACPI_ADR_SPACE_GSBUS,
331	&acpi_i2c_space_handler,
332	NULL,
333	data);
334	if (ACPI_FAILURE(status)) {
335	dev_err(&adapter->dev, "Error installing i2c space handler\n");
336	acpi_bus_detach_private_data(handle);
337	kfree(data);
338	return -ENOMEM;
339	}
340
341	return 0;
342	}
343
344	void acpi_i2c_remove_space_handler(struct i2c_adapter *adapter)
345	{
346	acpi_handle handle = ACPI_HANDLE(adapter->dev.parent);
347	struct acpi_i2c_handler_data *data;
348	acpi_status status;
349
350	if (!handle)
351	return;
352
353	acpi_remove_address_space_handler(handle,
354	ACPI_ADR_SPACE_GSBUS,
355	&acpi_i2c_space_handler);
356
357	status = acpi_bus_get_private_data(handle, (void **)&data);
358	if (ACPI_SUCCESS(status))
359	kfree(data);
360
361	acpi_bus_detach_private_data(handle);
362	}