blob: aa7c70ef94f5f7d51017c0b63491f5c8ac88f794 [file] [log] [blame]
* NVEC: NVIDIA compliant embedded controller interface
* Copyright (C) 2011 The AC100 Kernel Team <>
* Authors: Pierre-Hugues Husson <>
* Ilya Petrov <>
* Marc Dietrich <>
* Julian Andres Klode <>
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
#ifndef __LINUX_MFD_NVEC
#define __LINUX_MFD_NVEC
#include <linux/atomic.h>
#include <linux/clk.h>
#include <linux/completion.h>
#include <linux/list.h>
#include <linux/mutex.h>
#include <linux/notifier.h>
#include <linux/reset.h>
#include <linux/spinlock.h>
#include <linux/workqueue.h>
/* NVEC_POOL_SIZE - Size of the pool in &struct nvec_msg */
#define NVEC_POOL_SIZE 64
* NVEC_MSG_SIZE - Maximum size of the data field of &struct nvec_msg.
* A message must store up to a SMBus block operation which consists of
* one command byte, one count byte, and up to 32 payload bytes = 34
* byte.
#define NVEC_MSG_SIZE 34
* enum nvec_event_size - The size of an event message
* @NVEC_2BYTES: The message has one command byte and one data byte
* @NVEC_3BYTES: The message has one command byte and two data bytes
* @NVEC_VAR_SIZE: The message has one command byte, one count byte, and has
* up to as many bytes as the number in the count byte. The
* maximum is 32
* Events can be fixed or variable sized. This is useless on other message
* types, which are always variable sized.
enum nvec_event_size {
* enum nvec_msg_type - The type of a message
* @NVEC_SYS: A system request/response
* @NVEC_BAT: A battery request/response
* @NVEC_KBD: A keyboard request/response
* @NVEC_PS2: A mouse request/response
* @NVEC_CNTL: A EC control request/response
* @NVEC_KB_EVT: An event from the keyboard
* @NVEC_PS2_EVT: An event from the mouse
* Events can be fixed or variable sized. This is useless on other message
* types, which are always variable sized.
enum nvec_msg_type {
NVEC_OEM0 = 0x0d,
NVEC_KB_EVT = 0x80,
* struct nvec_msg - A buffer for a single message
* @node: Messages are part of various lists in a &struct nvec_chip
* @data: The data of the message
* @size: For TX messages, the number of bytes used in @data
* @pos: For RX messages, the current position to write to. For TX messages,
* the position to read from.
* @used: Used for the message pool to mark a message as free/allocated.
* This structure is used to hold outgoing and incoming messages. Outgoing
* messages have a different format than incoming messages, and that is not
* documented yet.
struct nvec_msg {
struct list_head node;
unsigned char data[NVEC_MSG_SIZE];
unsigned short size;
unsigned short pos;
atomic_t used;
* struct nvec_chip - A single connection to an NVIDIA Embedded controller
* @dev: The device
* @gpio: The same as for &struct nvec_platform_data
* @irq: The IRQ of the I2C device
* @i2c_addr: The address of the I2C slave
* @base: The base of the memory mapped region of the I2C device
* @i2c_clk: The clock of the I2C device
* @rst: The reset of the I2C device
* @notifier_list: Notifiers to be called on received messages, see
* nvec_register_notifier()
* @rx_data: Received messages that have to be processed
* @tx_data: Messages waiting to be sent to the controller
* @nvec_status_notifier: Internal notifier (see nvec_status_notifier())
* @rx_work: A work structure for the RX worker nvec_dispatch()
* @tx_work: A work structure for the TX worker nvec_request_master()
* @wq: The work queue in which @rx_work and @tx_work are executed
* @rx: The message currently being retrieved or %NULL
* @msg_pool: A pool of messages for allocation
* @tx: The message currently being transferred
* @tx_scratch: Used for building pseudo messages
* @ec_transfer: A completion that will be completed once a message has been
* received (see nvec_rx_completed())
* @tx_lock: Spinlock for modifications on @tx_data
* @rx_lock: Spinlock for modifications on @rx_data
* @sync_write_mutex: A mutex for nvec_write_sync()
* @sync_write: A completion to signal that a synchronous message is complete
* @sync_write_pending: The first two bytes of the request (type and subtype)
* @last_sync_msg: The last synchronous message.
* @state: State of our finite state machine used in nvec_interrupt()
struct nvec_chip {
struct device *dev;
int gpio;
int irq;
u32 i2c_addr;
void __iomem *base;
struct clk *i2c_clk;
struct reset_control *rst;
struct atomic_notifier_head notifier_list;
struct list_head rx_data, tx_data;
struct notifier_block nvec_status_notifier;
struct work_struct rx_work, tx_work;
struct workqueue_struct *wq;
struct nvec_msg msg_pool[NVEC_POOL_SIZE];
struct nvec_msg *rx;
struct nvec_msg *tx;
struct nvec_msg tx_scratch;
struct completion ec_transfer;
spinlock_t tx_lock, rx_lock;
/* sync write stuff */
struct mutex sync_write_mutex;
struct completion sync_write;
u16 sync_write_pending;
struct nvec_msg *last_sync_msg;
int state;
int nvec_write_async(struct nvec_chip *nvec, const unsigned char *data,
short size);
int nvec_write_sync(struct nvec_chip *nvec,
const unsigned char *data, short size,
struct nvec_msg **msg);
int nvec_register_notifier(struct nvec_chip *nvec,
struct notifier_block *nb,
unsigned int events);
int nvec_unregister_notifier(struct nvec_chip *dev, struct notifier_block *nb);
void nvec_msg_free(struct nvec_chip *nvec, struct nvec_msg *msg);