[linux-2.6-block.git] / drivers / acpi / sbshc.c

/*
 * SMBus driver for ACPI Embedded Controller (v0.1)
 *
 * Copyright (c) 2007 Alexey Starikovskiy
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation version 2.
 */

#include <linux/acpi.h>
#include <linux/wait.h>
#include <linux/slab.h>
#include <linux/delay.h>
#include <linux/module.h>
#include <linux/interrupt.h>
#include "sbshc.h"

#define PREFIX "ACPI: "

#define ACPI_SMB_HC_CLASS	"smbus_host_ctl"
#define ACPI_SMB_HC_DEVICE_NAME	"ACPI SMBus HC"

struct acpi_smb_hc {
	struct acpi_ec *ec;
	struct mutex lock;
	wait_queue_head_t wait;
	u8 offset;
	u8 query_bit;
	smbus_alarm_callback callback;
	void *context;
	bool done;
};

static int acpi_smbus_hc_add(struct acpi_device *device);
static int acpi_smbus_hc_remove(struct acpi_device *device);

static const struct acpi_device_id sbs_device_ids[] = {
	{"ACPI0001", 0},
	{"ACPI0005", 0},
	{"", 0},
};

MODULE_DEVICE_TABLE(acpi, sbs_device_ids);

static struct acpi_driver acpi_smb_hc_driver = {
	.name = "smbus_hc",
	.class = ACPI_SMB_HC_CLASS,
	.ids = sbs_device_ids,
	.ops = {
		.add = acpi_smbus_hc_add,
		.remove = acpi_smbus_hc_remove,
		},
};

union acpi_smb_status {
	u8 raw;
	struct {
		u8 status:5;
		u8 reserved:1;
		u8 alarm:1;
		u8 done:1;
	} fields;
};

enum acpi_smb_status_codes {
	SMBUS_OK = 0,
	SMBUS_UNKNOWN_FAILURE = 0x07,
	SMBUS_DEVICE_ADDRESS_NACK = 0x10,
	SMBUS_DEVICE_ERROR = 0x11,
	SMBUS_DEVICE_COMMAND_ACCESS_DENIED = 0x12,
	SMBUS_UNKNOWN_ERROR = 0x13,
	SMBUS_DEVICE_ACCESS_DENIED = 0x17,
	SMBUS_TIMEOUT = 0x18,
	SMBUS_HOST_UNSUPPORTED_PROTOCOL = 0x19,
	SMBUS_BUSY = 0x1a,
	SMBUS_PEC_ERROR = 0x1f,
};

enum acpi_smb_offset {
	ACPI_SMB_PROTOCOL = 0,	/* protocol, PEC */
	ACPI_SMB_STATUS = 1,	/* status */
	ACPI_SMB_ADDRESS = 2,	/* address */
	ACPI_SMB_COMMAND = 3,	/* command */
	ACPI_SMB_DATA = 4,	/* 32 data registers */
	ACPI_SMB_BLOCK_COUNT = 0x24,	/* number of data bytes */
	ACPI_SMB_ALARM_ADDRESS = 0x25,	/* alarm address */
	ACPI_SMB_ALARM_DATA = 0x26,	/* 2 bytes alarm data */
};

static inline int smb_hc_read(struct acpi_smb_hc *hc, u8 address, u8 *data)
{
	return ec_read(hc->offset + address, data);
}

static inline int smb_hc_write(struct acpi_smb_hc *hc, u8 address, u8 data)
{
	return ec_write(hc->offset + address, data);
}

static int wait_transaction_complete(struct acpi_smb_hc *hc, int timeout)
{
	if (wait_event_timeout(hc->wait, hc->done, msecs_to_jiffies(timeout)))
		return 0;
	return -ETIME;
}

static int acpi_smbus_transaction(struct acpi_smb_hc *hc, u8 protocol,
				  u8 address, u8 command, u8 *data, u8 length)
{
	int ret = -EFAULT, i;
	u8 temp, sz = 0;

	if (!hc) {
		printk(KERN_ERR PREFIX "host controller is not configured\n");
		return ret;
	}

	mutex_lock(&hc->lock);
	hc->done = false;
	if (smb_hc_read(hc, ACPI_SMB_PROTOCOL, &temp))
		goto end;
	if (temp) {
		ret = -EBUSY;
		goto end;
	}
	smb_hc_write(hc, ACPI_SMB_COMMAND, command);
	if (!(protocol & 0x01)) {
		smb_hc_write(hc, ACPI_SMB_BLOCK_COUNT, length);
		for (i = 0; i < length; ++i)
			smb_hc_write(hc, ACPI_SMB_DATA + i, data[i]);
	}
	smb_hc_write(hc, ACPI_SMB_ADDRESS, address << 1);
	smb_hc_write(hc, ACPI_SMB_PROTOCOL, protocol);
	/*
	 * Wait for completion. Save the status code, data size,
	 * and data into the return package (if required by the protocol).
	 */
	ret = wait_transaction_complete(hc, 1000);
	if (ret || !(protocol & 0x01))
		goto end;
	switch (protocol) {
	case SMBUS_RECEIVE_BYTE:
	case SMBUS_READ_BYTE:
		sz = 1;
		break;
	case SMBUS_READ_WORD:
		sz = 2;
		break;
	case SMBUS_READ_BLOCK:
		if (smb_hc_read(hc, ACPI_SMB_BLOCK_COUNT, &sz)) {
			ret = -EFAULT;
			goto end;
		}
		sz &= 0x1f;
		break;
	}
	for (i = 0; i < sz; ++i)
		smb_hc_read(hc, ACPI_SMB_DATA + i, &data[i]);
      end:
	mutex_unlock(&hc->lock);
	return ret;
}

int acpi_smbus_read(struct acpi_smb_hc *hc, u8 protocol, u8 address,
		    u8 command, u8 *data)
{
	return acpi_smbus_transaction(hc, protocol, address, command, data, 0);
}

EXPORT_SYMBOL_GPL(acpi_smbus_read);

int acpi_smbus_write(struct acpi_smb_hc *hc, u8 protocol, u8 address,
		     u8 command, u8 *data, u8 length)
{
	return acpi_smbus_transaction(hc, protocol, address, command, data, length);
}

EXPORT_SYMBOL_GPL(acpi_smbus_write);

int acpi_smbus_register_callback(struct acpi_smb_hc *hc,
			         smbus_alarm_callback callback, void *context)
{
	mutex_lock(&hc->lock);
	hc->callback = callback;
	hc->context = context;
	mutex_unlock(&hc->lock);
	return 0;
}

EXPORT_SYMBOL_GPL(acpi_smbus_register_callback);

int acpi_smbus_unregister_callback(struct acpi_smb_hc *hc)
{
	mutex_lock(&hc->lock);
	hc->callback = NULL;
	hc->context = NULL;
	mutex_unlock(&hc->lock);
	acpi_os_wait_events_complete();
	return 0;
}

EXPORT_SYMBOL_GPL(acpi_smbus_unregister_callback);

static inline void acpi_smbus_callback(void *context)
{
	struct acpi_smb_hc *hc = context;
	if (hc->callback)
		hc->callback(hc->context);
}

static int smbus_alarm(void *context)
{
	struct acpi_smb_hc *hc = context;
	union acpi_smb_status status;
	u8 address;
	if (smb_hc_read(hc, ACPI_SMB_STATUS, &status.raw))
		return 0;
	/* Check if it is only a completion notify */
	if (status.fields.done && status.fields.status == SMBUS_OK) {
		hc->done = true;
		wake_up(&hc->wait);
	}
	if (!status.fields.alarm)
		return 0;
	mutex_lock(&hc->lock);
	smb_hc_read(hc, ACPI_SMB_ALARM_ADDRESS, &address);
	status.fields.alarm = 0;
	smb_hc_write(hc, ACPI_SMB_STATUS, status.raw);
	/* We are only interested in events coming from known devices */
	switch (address >> 1) {
		case ACPI_SBS_CHARGER:
		case ACPI_SBS_MANAGER:
		case ACPI_SBS_BATTERY:
			acpi_os_execute(OSL_NOTIFY_HANDLER,
					acpi_smbus_callback, hc);
		default:;
	}
	mutex_unlock(&hc->lock);
	return 0;
}

typedef int (*acpi_ec_query_func) (void *data);

extern int acpi_ec_add_query_handler(struct acpi_ec *ec, u8 query_bit,
			      acpi_handle handle, acpi_ec_query_func func,
			      void *data);

static int acpi_smbus_hc_add(struct acpi_device *device)
{
	int status;
	unsigned long long val;
	struct acpi_smb_hc *hc;

	if (!device)
		return -EINVAL;

	status = acpi_evaluate_integer(device->handle, "_EC", NULL, &val);
	if (ACPI_FAILURE(status)) {
		printk(KERN_ERR PREFIX "error obtaining _EC.\n");
		return -EIO;
	}

	strcpy(acpi_device_name(device), ACPI_SMB_HC_DEVICE_NAME);
	strcpy(acpi_device_class(device), ACPI_SMB_HC_CLASS);

	hc = kzalloc(sizeof(struct acpi_smb_hc), GFP_KERNEL);
	if (!hc)
		return -ENOMEM;
	mutex_init(&hc->lock);
	init_waitqueue_head(&hc->wait);

	hc->ec = acpi_driver_data(device->parent);
	hc->offset = (val >> 8) & 0xff;
	hc->query_bit = val & 0xff;
	device->driver_data = hc;

	acpi_ec_add_query_handler(hc->ec, hc->query_bit, NULL, smbus_alarm, hc);
	dev_info(&device->dev, "SBS HC: offset = 0x%0x, query_bit = 0x%0x\n",
		 hc->offset, hc->query_bit);

	return 0;
}

extern void acpi_ec_remove_query_handler(struct acpi_ec *ec, u8 query_bit);

static int acpi_smbus_hc_remove(struct acpi_device *device)
{
	struct acpi_smb_hc *hc;

	if (!device)
		return -EINVAL;

	hc = acpi_driver_data(device);
	acpi_ec_remove_query_handler(hc->ec, hc->query_bit);
	acpi_os_wait_events_complete();
	kfree(hc);
	device->driver_data = NULL;
	return 0;
}

module_acpi_driver(acpi_smb_hc_driver);

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Alexey Starikovskiy");
MODULE_DESCRIPTION("ACPI SMBus HC driver");
Commit	Line	Data
91087dfa AS	1	/*
	2	* SMBus driver for ACPI Embedded Controller (v0.1)
	3	*
	4	* Copyright (c) 2007 Alexey Starikovskiy
	5	*
	6	* This program is free software; you can redistribute it and/or modify
	7	* it under the terms of the GNU General Public License as published by
	8	* the Free Software Foundation version 2.
	9	*/
	10
8b48463f	11	#include <linux/acpi.h>
91087dfa	12	#include <linux/wait.h>
5a0e3ad6	13	#include <linux/slab.h>
91087dfa	14	#include <linux/delay.h>
cc4b859c	15	#include <linux/module.h>
91087dfa AS	16	#include <linux/interrupt.h>
	17	#include "sbshc.h"
	18
a192a958 LB	19	#define PREFIX "ACPI: "
a192a958 LB	20
97c227cb	21	#define ACPI_SMB_HC_CLASS "smbus_host_ctl"
91087dfa AS	22	#define ACPI_SMB_HC_DEVICE_NAME "ACPI SMBus HC"
	23
	24	struct acpi_smb_hc {
	25	struct acpi_ec *ec;
	26	struct mutex lock;
	27	wait_queue_head_t wait;
	28	u8 offset;
	29	u8 query_bit;
	30	smbus_alarm_callback callback;
	31	void *context;
add68d6a	32	bool done;
91087dfa AS	33	};
	34
	35	static int acpi_smbus_hc_add(struct acpi_device *device);
51fac838	36	static int acpi_smbus_hc_remove(struct acpi_device *device);
91087dfa AS	37
	38	static const struct acpi_device_id sbs_device_ids[] = {
	39	{"ACPI0001", 0},
	40	{"ACPI0005", 0},
	41	{"", 0},
	42	};
	43
	44	MODULE_DEVICE_TABLE(acpi, sbs_device_ids);
	45
	46	static struct acpi_driver acpi_smb_hc_driver = {
	47	.name = "smbus_hc",
	48	.class = ACPI_SMB_HC_CLASS,
	49	.ids = sbs_device_ids,
	50	.ops = {
	51	.add = acpi_smbus_hc_add,
	52	.remove = acpi_smbus_hc_remove,
	53	},
	54	};
	55
	56	union acpi_smb_status {
	57	u8 raw;
	58	struct {
	59	u8 status:5;
	60	u8 reserved:1;
	61	u8 alarm:1;
	62	u8 done:1;
	63	} fields;
	64	};
	65
	66	enum acpi_smb_status_codes {
	67	SMBUS_OK = 0,
	68	SMBUS_UNKNOWN_FAILURE = 0x07,
	69	SMBUS_DEVICE_ADDRESS_NACK = 0x10,
	70	SMBUS_DEVICE_ERROR = 0x11,
	71	SMBUS_DEVICE_COMMAND_ACCESS_DENIED = 0x12,
	72	SMBUS_UNKNOWN_ERROR = 0x13,
	73	SMBUS_DEVICE_ACCESS_DENIED = 0x17,
	74	SMBUS_TIMEOUT = 0x18,
	75	SMBUS_HOST_UNSUPPORTED_PROTOCOL = 0x19,
	76	SMBUS_BUSY = 0x1a,
	77	SMBUS_PEC_ERROR = 0x1f,
	78	};
	79
	80	enum acpi_smb_offset {
	81	ACPI_SMB_PROTOCOL = 0, /* protocol, PEC */
	82	ACPI_SMB_STATUS = 1, /* status */
	83	ACPI_SMB_ADDRESS = 2, /* address */
	84	ACPI_SMB_COMMAND = 3, /* command */
	85	ACPI_SMB_DATA = 4, /* 32 data registers */
	86	ACPI_SMB_BLOCK_COUNT = 0x24, /* number of data bytes */
	87	ACPI_SMB_ALARM_ADDRESS = 0x25, /* alarm address */
	88	ACPI_SMB_ALARM_DATA = 0x26, /* 2 bytes alarm data */
	89	};
	90
	91	static inline int smb_hc_read(struct acpi_smb_hc hc, u8 address, u8 data)
	92	{
	93	return ec_read(hc->offset + address, data);
	94	}
	95
	96	static inline int smb_hc_write(struct acpi_smb_hc *hc, u8 address, u8 data)
	97	{
	98	return ec_write(hc->offset + address, data);
	99	}
	100
91087dfa AS	101	static int wait_transaction_complete(struct acpi_smb_hc *hc, int timeout)
91087dfa AS	102	{
add68d6a	103	if (wait_event_timeout(hc->wait, hc->done, msecs_to_jiffies(timeout)))
91087dfa	104	return 0;
add68d6a	105	return -ETIME;
91087dfa AS	106	}
91087dfa AS	107
e5685b9d AB	108	static int acpi_smbus_transaction(struct acpi_smb_hc *hc, u8 protocol,
e5685b9d AB	109	u8 address, u8 command, u8 *data, u8 length)
91087dfa AS	110	{
	111	int ret = -EFAULT, i;
	112	u8 temp, sz = 0;
	113
bbafbecb AS	114	if (!hc) {
	115	printk(KERN_ERR PREFIX "host controller is not configured\n");
	116	return ret;
	117	}
	118
91087dfa	119	mutex_lock(&hc->lock);
add68d6a	120	hc->done = false;
91087dfa AS	121	if (smb_hc_read(hc, ACPI_SMB_PROTOCOL, &temp))
	122	goto end;
	123	if (temp) {
	124	ret = -EBUSY;
	125	goto end;
	126	}
	127	smb_hc_write(hc, ACPI_SMB_COMMAND, command);
91087dfa AS	128	if (!(protocol & 0x01)) {
	129	smb_hc_write(hc, ACPI_SMB_BLOCK_COUNT, length);
	130	for (i = 0; i < length; ++i)
	131	smb_hc_write(hc, ACPI_SMB_DATA + i, data[i]);
	132	}
	133	smb_hc_write(hc, ACPI_SMB_ADDRESS, address << 1);
	134	smb_hc_write(hc, ACPI_SMB_PROTOCOL, protocol);
	135	/*
	136	* Wait for completion. Save the status code, data size,
	137	* and data into the return package (if required by the protocol).
	138	*/
	139	ret = wait_transaction_complete(hc, 1000);
	140	if (ret \|\| !(protocol & 0x01))
	141	goto end;
	142	switch (protocol) {
	143	case SMBUS_RECEIVE_BYTE:
	144	case SMBUS_READ_BYTE:
	145	sz = 1;
	146	break;
	147	case SMBUS_READ_WORD:
	148	sz = 2;
	149	break;
	150	case SMBUS_READ_BLOCK:
	151	if (smb_hc_read(hc, ACPI_SMB_BLOCK_COUNT, &sz)) {
	152	ret = -EFAULT;
	153	goto end;
	154	}
	155	sz &= 0x1f;
	156	break;
	157	}
	158	for (i = 0; i < sz; ++i)
	159	smb_hc_read(hc, ACPI_SMB_DATA + i, &data[i]);
	160	end:
	161	mutex_unlock(&hc->lock);
	162	return ret;
	163	}
	164
	165	int acpi_smbus_read(struct acpi_smb_hc *hc, u8 protocol, u8 address,
	166	u8 command, u8 *data)
	167	{
	168	return acpi_smbus_transaction(hc, protocol, address, command, data, 0);
	169	}
	170
	171	EXPORT_SYMBOL_GPL(acpi_smbus_read);
	172
	173	int acpi_smbus_write(struct acpi_smb_hc *hc, u8 protocol, u8 address,
	174	u8 command, u8 *data, u8 length)
	175	{
	176	return acpi_smbus_transaction(hc, protocol, address, command, data, length);
	177	}
	178
	179	EXPORT_SYMBOL_GPL(acpi_smbus_write);
	180
	181	int acpi_smbus_register_callback(struct acpi_smb_hc *hc,
	182	smbus_alarm_callback callback, void *context)
	183	{
	184	mutex_lock(&hc->lock);
	185	hc->callback = callback;
	186	hc->context = context;
	187	mutex_unlock(&hc->lock);
	188	return 0;
	189	}
	190
	191	EXPORT_SYMBOL_GPL(acpi_smbus_register_callback);
192
193	int acpi_smbus_unregister_callback(struct acpi_smb_hc *hc)
194	{
195	mutex_lock(&hc->lock);
196	hc->callback = NULL;
197	hc->context = NULL;
198	mutex_unlock(&hc->lock);
757c968c	199	acpi_os_wait_events_complete();
91087dfa AS	200	return 0;
	201	}
	202
	203	EXPORT_SYMBOL_GPL(acpi_smbus_unregister_callback);
	204
c2d00f2d	205	static inline void acpi_smbus_callback(void *context)
91087dfa AS	206	{
91087dfa AS	207	struct acpi_smb_hc *hc = context;
91087dfa AS	208	if (hc->callback)
	209	hc->callback(hc->context);
	210	}
	211
	212	static int smbus_alarm(void *context)
	213	{
	214	struct acpi_smb_hc *hc = context;
	215	union acpi_smb_status status;
c2d00f2d	216	u8 address;
91087dfa AS	217	if (smb_hc_read(hc, ACPI_SMB_STATUS, &status.raw))
	218	return 0;
	219	/* Check if it is only a completion notify */
add68d6a CB	220	if (status.fields.done && status.fields.status == SMBUS_OK) {
add68d6a CB	221	hc->done = true;
91087dfa	222	wake_up(&hc->wait);
add68d6a	223	}
91087dfa AS	224	if (!status.fields.alarm)
	225	return 0;
	226	mutex_lock(&hc->lock);
c2d00f2d	227	smb_hc_read(hc, ACPI_SMB_ALARM_ADDRESS, &address);
09f1fb41	228	status.fields.alarm = 0;
91087dfa	229	smb_hc_write(hc, ACPI_SMB_STATUS, status.raw);
c2d00f2d AS	230	/* We are only interested in events coming from known devices */
	231	switch (address >> 1) {
	232	case ACPI_SBS_CHARGER:
	233	case ACPI_SBS_MANAGER:
	234	case ACPI_SBS_BATTERY:
f5347867	235	acpi_os_execute(OSL_NOTIFY_HANDLER,
c2d00f2d AS	236	acpi_smbus_callback, hc);
	237	default:;
	238	}
91087dfa AS	239	mutex_unlock(&hc->lock);
	240	return 0;
	241	}
	242
	243	typedef int (acpi_ec_query_func) (void data);
	244
	245	extern int acpi_ec_add_query_handler(struct acpi_ec *ec, u8 query_bit,
	246	acpi_handle handle, acpi_ec_query_func func,
	247	void *data);
	248
	249	static int acpi_smbus_hc_add(struct acpi_device *device)
	250	{
	251	int status;
27663c58	252	unsigned long long val;
91087dfa AS	253	struct acpi_smb_hc *hc;
	254
	255	if (!device)
	256	return -EINVAL;
	257
	258	status = acpi_evaluate_integer(device->handle, "_EC", NULL, &val);
	259	if (ACPI_FAILURE(status)) {
	260	printk(KERN_ERR PREFIX "error obtaining _EC.\n");
	261	return -EIO;
	262	}
	263
	264	strcpy(acpi_device_name(device), ACPI_SMB_HC_DEVICE_NAME);
	265	strcpy(acpi_device_class(device), ACPI_SMB_HC_CLASS);
	266
	267	hc = kzalloc(sizeof(struct acpi_smb_hc), GFP_KERNEL);
	268	if (!hc)
	269	return -ENOMEM;
	270	mutex_init(&hc->lock);
	271	init_waitqueue_head(&hc->wait);
	272
	273	hc->ec = acpi_driver_data(device->parent);
	274	hc->offset = (val >> 8) & 0xff;
	275	hc->query_bit = val & 0xff;
db89b4f0	276	device->driver_data = hc;
91087dfa AS	277
91087dfa AS	278	acpi_ec_add_query_handler(hc->ec, hc->query_bit, NULL, smbus_alarm, hc);
43cdd1b7 GKH	279	dev_info(&device->dev, "SBS HC: offset = 0x%0x, query_bit = 0x%0x\n",
43cdd1b7 GKH	280	hc->offset, hc->query_bit);
91087dfa AS	281
	282	return 0;
	283	}
	284
	285	extern void acpi_ec_remove_query_handler(struct acpi_ec *ec, u8 query_bit);
	286
51fac838	287	static int acpi_smbus_hc_remove(struct acpi_device *device)
91087dfa AS	288	{
	289	struct acpi_smb_hc *hc;
	290
	291	if (!device)
	292	return -EINVAL;
	293
	294	hc = acpi_driver_data(device);
	295	acpi_ec_remove_query_handler(hc->ec, hc->query_bit);
757c968c	296	acpi_os_wait_events_complete();
91087dfa	297	kfree(hc);
db89b4f0	298	device->driver_data = NULL;
91087dfa AS	299	return 0;
	300	}
	301
e84a239e	302	module_acpi_driver(acpi_smb_hc_driver);
91087dfa AS	303
	304	MODULE_LICENSE("GPL");
	305	MODULE_AUTHOR("Alexey Starikovskiy");
	306	MODULE_DESCRIPTION("ACPI SMBus HC driver");