[linux.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 <acpi/acpi_bus.h>
#include <acpi/acpi_drivers.h>
#include <acpi/actypes.h>
#include <linux/wait.h>
#include <linux/delay.h>
#include <linux/interrupt.h>
#include "sbshc.h"

#define ACPI_SMB_HC_CLASS	"smbus_host_controller"
#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;
};

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

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 inline int smb_check_done(struct acpi_smb_hc *hc)
{
	union acpi_smb_status status = {.raw = 0};
	smb_hc_read(hc, ACPI_SMB_STATUS, &status.raw);
	return status.fields.done && (status.fields.status == SMBUS_OK);
}

static int wait_transaction_complete(struct acpi_smb_hc *hc, int timeout)
{
	if (wait_event_timeout(hc->wait, smb_check_done(hc),
			       msecs_to_jiffies(timeout)))
		return 0;
	else
		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);
	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);
	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)
		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_GPE_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 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;
	acpi_driver_data(device) = hc;

	acpi_ec_add_query_handler(hc->ec, hc->query_bit, NULL, smbus_alarm, hc);
	printk(KERN_INFO PREFIX "SBS HC: EC = 0x%p, offset = 0x%0x, query_bit = 0x%0x\n",
		hc->ec, 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, int type)
{
	struct acpi_smb_hc *hc;

	if (!device)
		return -EINVAL;

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

static int __init acpi_smb_hc_init(void)
{
	int result;

	result = acpi_bus_register_driver(&acpi_smb_hc_driver);
	if (result < 0)
		return -ENODEV;
	return 0;
}

static void __exit acpi_smb_hc_exit(void)
{
	acpi_bus_unregister_driver(&acpi_smb_hc_driver);
}

module_init(acpi_smb_hc_init);
module_exit(acpi_smb_hc_exit);

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
	11	#include <acpi/acpi_bus.h>
	12	#include <acpi/acpi_drivers.h>
	13	#include <acpi/actypes.h>
	14	#include <linux/wait.h>
	15	#include <linux/delay.h>
	16	#include <linux/interrupt.h>
	17	#include "sbshc.h"
	18
	19	#define ACPI_SMB_HC_CLASS "smbus_host_controller"
	20	#define ACPI_SMB_HC_DEVICE_NAME "ACPI SMBus HC"
	21
	22	struct acpi_smb_hc {
	23	struct acpi_ec *ec;
	24	struct mutex lock;
	25	wait_queue_head_t wait;
	26	u8 offset;
	27	u8 query_bit;
	28	smbus_alarm_callback callback;
	29	void *context;
	30	};
	31
	32	static int acpi_smbus_hc_add(struct acpi_device *device);
	33	static int acpi_smbus_hc_remove(struct acpi_device *device, int type);
	34
	35	static const struct acpi_device_id sbs_device_ids[] = {
	36	{"ACPI0001", 0},
	37	{"ACPI0005", 0},
	38	{"", 0},
	39	};
	40
	41	MODULE_DEVICE_TABLE(acpi, sbs_device_ids);
	42
	43	static struct acpi_driver acpi_smb_hc_driver = {
	44	.name = "smbus_hc",
	45	.class = ACPI_SMB_HC_CLASS,
	46	.ids = sbs_device_ids,
	47	.ops = {
	48	.add = acpi_smbus_hc_add,
	49	.remove = acpi_smbus_hc_remove,
	50	},
	51	};
	52
	53	union acpi_smb_status {
	54	u8 raw;
	55	struct {
	56	u8 status:5;
	57	u8 reserved:1;
	58	u8 alarm:1;
	59	u8 done:1;
	60	} fields;
	61	};
	62
	63	enum acpi_smb_status_codes {
	64	SMBUS_OK = 0,
65	SMBUS_UNKNOWN_FAILURE = 0x07,
66	SMBUS_DEVICE_ADDRESS_NACK = 0x10,
67	SMBUS_DEVICE_ERROR = 0x11,
68	SMBUS_DEVICE_COMMAND_ACCESS_DENIED = 0x12,
69	SMBUS_UNKNOWN_ERROR = 0x13,
70	SMBUS_DEVICE_ACCESS_DENIED = 0x17,
71	SMBUS_TIMEOUT = 0x18,
72	SMBUS_HOST_UNSUPPORTED_PROTOCOL = 0x19,
73	SMBUS_BUSY = 0x1a,
74	SMBUS_PEC_ERROR = 0x1f,
75	};
76
77	enum acpi_smb_offset {
78	ACPI_SMB_PROTOCOL = 0, /* protocol, PEC */
79	ACPI_SMB_STATUS = 1, /* status */
80	ACPI_SMB_ADDRESS = 2, /* address */
81	ACPI_SMB_COMMAND = 3, /* command */
82	ACPI_SMB_DATA = 4, /* 32 data registers */
83	ACPI_SMB_BLOCK_COUNT = 0x24, /* number of data bytes */
84	ACPI_SMB_ALARM_ADDRESS = 0x25, /* alarm address */
85	ACPI_SMB_ALARM_DATA = 0x26, /* 2 bytes alarm data */
86	};
87
88	static inline int smb_hc_read(struct acpi_smb_hc hc, u8 address, u8 data)
89	{
90	return ec_read(hc->offset + address, data);
91	}
92
93	static inline int smb_hc_write(struct acpi_smb_hc *hc, u8 address, u8 data)
94	{
95	return ec_write(hc->offset + address, data);
96	}
97
98	static inline int smb_check_done(struct acpi_smb_hc *hc)
99	{
100	union acpi_smb_status status = {.raw = 0};
101	smb_hc_read(hc, ACPI_SMB_STATUS, &status.raw);
102	return status.fields.done && (status.fields.status == SMBUS_OK);
103	}
104
105	static int wait_transaction_complete(struct acpi_smb_hc *hc, int timeout)
106	{
107	if (wait_event_timeout(hc->wait, smb_check_done(hc),
108	msecs_to_jiffies(timeout)))
109	return 0;
110	else
111	return -ETIME;
112	}
113
e5685b9d AB	114	static int acpi_smbus_transaction(struct acpi_smb_hc *hc, u8 protocol,
e5685b9d AB	115	u8 address, u8 command, u8 *data, u8 length)
91087dfa AS	116	{
	117	int ret = -EFAULT, i;
	118	u8 temp, sz = 0;
	119
bbafbecb AS	120	if (!hc) {
	121	printk(KERN_ERR PREFIX "host controller is not configured\n");
	122	return ret;
	123	}
	124
91087dfa AS	125	mutex_lock(&hc->lock);
	126	if (smb_hc_read(hc, ACPI_SMB_PROTOCOL, &temp))
	127	goto end;
	128	if (temp) {
	129	ret = -EBUSY;
	130	goto end;
	131	}
	132	smb_hc_write(hc, ACPI_SMB_COMMAND, command);
91087dfa AS	133	if (!(protocol & 0x01)) {
	134	smb_hc_write(hc, ACPI_SMB_BLOCK_COUNT, length);
	135	for (i = 0; i < length; ++i)
	136	smb_hc_write(hc, ACPI_SMB_DATA + i, data[i]);
	137	}
	138	smb_hc_write(hc, ACPI_SMB_ADDRESS, address << 1);
	139	smb_hc_write(hc, ACPI_SMB_PROTOCOL, protocol);
	140	/*
	141	* Wait for completion. Save the status code, data size,
	142	* and data into the return package (if required by the protocol).
	143	*/
	144	ret = wait_transaction_complete(hc, 1000);
	145	if (ret \|\| !(protocol & 0x01))
	146	goto end;
	147	switch (protocol) {
	148	case SMBUS_RECEIVE_BYTE:
	149	case SMBUS_READ_BYTE:
	150	sz = 1;
	151	break;
	152	case SMBUS_READ_WORD:
	153	sz = 2;
	154	break;
	155	case SMBUS_READ_BLOCK:
	156	if (smb_hc_read(hc, ACPI_SMB_BLOCK_COUNT, &sz)) {
	157	ret = -EFAULT;
	158	goto end;
	159	}
	160	sz &= 0x1f;
	161	break;
	162	}
	163	for (i = 0; i < sz; ++i)
	164	smb_hc_read(hc, ACPI_SMB_DATA + i, &data[i]);
	165	end:
	166	mutex_unlock(&hc->lock);
	167	return ret;
	168	}
	169
	170	int acpi_smbus_read(struct acpi_smb_hc *hc, u8 protocol, u8 address,
	171	u8 command, u8 *data)
	172	{
	173	return acpi_smbus_transaction(hc, protocol, address, command, data, 0);
	174	}
	175
	176	EXPORT_SYMBOL_GPL(acpi_smbus_read);
	177
	178	int acpi_smbus_write(struct acpi_smb_hc *hc, u8 protocol, u8 address,
	179	u8 command, u8 *data, u8 length)
	180	{
	181	return acpi_smbus_transaction(hc, protocol, address, command, data, length);
	182	}
	183
	184	EXPORT_SYMBOL_GPL(acpi_smbus_write);
	185
	186	int acpi_smbus_register_callback(struct acpi_smb_hc *hc,
	187	smbus_alarm_callback callback, void *context)
	188	{
	189	mutex_lock(&hc->lock);
	190	hc->callback = callback;
	191	hc->context = context;
	192	mutex_unlock(&hc->lock);
	193	return 0;
	194	}
	195
	196	EXPORT_SYMBOL_GPL(acpi_smbus_register_callback);
197
198	int acpi_smbus_unregister_callback(struct acpi_smb_hc *hc)
199	{
200	mutex_lock(&hc->lock);
201	hc->callback = NULL;
202	hc->context = NULL;
203	mutex_unlock(&hc->lock);
204	return 0;
205	}
206
207	EXPORT_SYMBOL_GPL(acpi_smbus_unregister_callback);
208
c2d00f2d	209	static inline void acpi_smbus_callback(void *context)
91087dfa AS	210	{
91087dfa AS	211	struct acpi_smb_hc *hc = context;
91087dfa AS	212	if (hc->callback)
	213	hc->callback(hc->context);
	214	}
	215
	216	static int smbus_alarm(void *context)
	217	{
	218	struct acpi_smb_hc *hc = context;
	219	union acpi_smb_status status;
c2d00f2d	220	u8 address;
91087dfa AS	221	if (smb_hc_read(hc, ACPI_SMB_STATUS, &status.raw))
	222	return 0;
	223	/* Check if it is only a completion notify */
	224	if (status.fields.done)
	225	wake_up(&hc->wait);
	226	if (!status.fields.alarm)
	227	return 0;
	228	mutex_lock(&hc->lock);
c2d00f2d	229	smb_hc_read(hc, ACPI_SMB_ALARM_ADDRESS, &address);
09f1fb41	230	status.fields.alarm = 0;
91087dfa	231	smb_hc_write(hc, ACPI_SMB_STATUS, status.raw);
c2d00f2d AS	232	/* We are only interested in events coming from known devices */
	233	switch (address >> 1) {
	234	case ACPI_SBS_CHARGER:
	235	case ACPI_SBS_MANAGER:
	236	case ACPI_SBS_BATTERY:
	237	acpi_os_execute(OSL_GPE_HANDLER,
	238	acpi_smbus_callback, hc);
	239	default:;
	240	}
91087dfa AS	241	mutex_unlock(&hc->lock);
	242	return 0;
	243	}
	244
	245	typedef int (acpi_ec_query_func) (void data);
	246
	247	extern int acpi_ec_add_query_handler(struct acpi_ec *ec, u8 query_bit,
	248	acpi_handle handle, acpi_ec_query_func func,
	249	void *data);
	250
	251	static int acpi_smbus_hc_add(struct acpi_device *device)
	252	{
	253	int status;
	254	unsigned long val;
	255	struct acpi_smb_hc *hc;
	256
	257	if (!device)
	258	return -EINVAL;
	259
	260	status = acpi_evaluate_integer(device->handle, "_EC", NULL, &val);
	261	if (ACPI_FAILURE(status)) {
	262	printk(KERN_ERR PREFIX "error obtaining _EC.\n");
	263	return -EIO;
	264	}
	265
	266	strcpy(acpi_device_name(device), ACPI_SMB_HC_DEVICE_NAME);
	267	strcpy(acpi_device_class(device), ACPI_SMB_HC_CLASS);
	268
	269	hc = kzalloc(sizeof(struct acpi_smb_hc), GFP_KERNEL);
	270	if (!hc)
	271	return -ENOMEM;
	272	mutex_init(&hc->lock);
	273	init_waitqueue_head(&hc->wait);
	274
	275	hc->ec = acpi_driver_data(device->parent);
	276	hc->offset = (val >> 8) & 0xff;
	277	hc->query_bit = val & 0xff;
	278	acpi_driver_data(device) = hc;
	279
	280	acpi_ec_add_query_handler(hc->ec, hc->query_bit, NULL, smbus_alarm, hc);
	281	printk(KERN_INFO PREFIX "SBS HC: EC = 0x%p, offset = 0x%0x, query_bit = 0x%0x\n",
	282	hc->ec, hc->offset, hc->query_bit);
	283
	284	return 0;
	285	}
	286
	287	extern void acpi_ec_remove_query_handler(struct acpi_ec *ec, u8 query_bit);
	288
	289	static int acpi_smbus_hc_remove(struct acpi_device *device, int type)
	290	{
	291	struct acpi_smb_hc *hc;
	292
	293	if (!device)
	294	return -EINVAL;
	295
	296	hc = acpi_driver_data(device);
	297	acpi_ec_remove_query_handler(hc->ec, hc->query_bit);
	298	kfree(hc);
bbafbecb	299	acpi_driver_data(device) = NULL;
91087dfa AS	300	return 0;
	301	}
	302
	303	static int __init acpi_smb_hc_init(void)
	304	{
	305	int result;
	306
	307	result = acpi_bus_register_driver(&acpi_smb_hc_driver);
	308	if (result < 0)
	309	return -ENODEV;
	310	return 0;
	311	}
	312
	313	static void __exit acpi_smb_hc_exit(void)
	314	{
	315	acpi_bus_unregister_driver(&acpi_smb_hc_driver);
	316	}
	317
	318	module_init(acpi_smb_hc_init);
	319	module_exit(acpi_smb_hc_exit);
	320
	321	MODULE_LICENSE("GPL");
	322	MODULE_AUTHOR("Alexey Starikovskiy");
	323	MODULE_DESCRIPTION("ACPI SMBus HC driver");