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1/* SPDX-License-Identifier: GPL-2.0 */2/*3 * NVEC: NVIDIA compliant embedded controller interface4 *5 * Copyright (C) 2011 The AC100 Kernel Team <ac100@lists.launchpad.net>6 *7 * Authors: Pierre-Hugues Husson <phhusson@free.fr>8 * Ilya Petrov <ilya.muromec@gmail.com>9 * Marc Dietrich <marvin24@gmx.de>10 * Julian Andres Klode <jak@jak-linux.org>11 */12 13#ifndef __LINUX_MFD_NVEC14#define __LINUX_MFD_NVEC15 16#include <linux/atomic.h>17#include <linux/clk.h>18#include <linux/completion.h>19#include <linux/list.h>20#include <linux/mutex.h>21#include <linux/notifier.h>22#include <linux/reset.h>23#include <linux/spinlock.h>24#include <linux/workqueue.h>25 26/* NVEC_POOL_SIZE - Size of the pool in &struct nvec_msg */27#define NVEC_POOL_SIZE 6428 29/*30 * NVEC_MSG_SIZE - Maximum size of the data field of &struct nvec_msg.31 *32 * A message must store up to a SMBus block operation which consists of33 * one command byte, one count byte, and up to 32 payload bytes = 3434 * byte.35 */36#define NVEC_MSG_SIZE 3437 38/**39 * enum nvec_event_size - The size of an event message40 * @NVEC_2BYTES: The message has one command byte and one data byte41 * @NVEC_3BYTES: The message has one command byte and two data bytes42 * @NVEC_VAR_SIZE: The message has one command byte, one count byte, and has43 * up to as many bytes as the number in the count byte. The44 * maximum is 3245 *46 * Events can be fixed or variable sized. This is useless on other message47 * types, which are always variable sized.48 */49enum nvec_event_size {50 NVEC_2BYTES,51 NVEC_3BYTES,52 NVEC_VAR_SIZE,53};54 55/**56 * enum nvec_msg_type - The type of a message57 * @NVEC_SYS: A system request/response58 * @NVEC_BAT: A battery request/response59 * @NVEC_KBD: A keyboard request/response60 * @NVEC_PS2: A mouse request/response61 * @NVEC_CNTL: A EC control request/response62 * @NVEC_KB_EVT: An event from the keyboard63 * @NVEC_PS2_EVT: An event from the mouse64 *65 * Events can be fixed or variable sized. This is useless on other message66 * types, which are always variable sized.67 */68enum nvec_msg_type {69 NVEC_SYS = 1,70 NVEC_BAT,71 NVEC_GPIO,72 NVEC_SLEEP,73 NVEC_KBD,74 NVEC_PS2,75 NVEC_CNTL,76 NVEC_OEM0 = 0x0d,77 NVEC_KB_EVT = 0x80,78 NVEC_PS2_EVT,79};80 81/**82 * struct nvec_msg - A buffer for a single message83 * @node: Messages are part of various lists in a &struct nvec_chip84 * @data: The data of the message85 * @size: For TX messages, the number of bytes used in @data86 * @pos: For RX messages, the current position to write to. For TX messages,87 * the position to read from.88 * @used: Used for the message pool to mark a message as free/allocated.89 *90 * This structure is used to hold outgoing and incoming messages. Outgoing91 * messages have a different format than incoming messages, and that is not92 * documented yet.93 */94struct nvec_msg {95 struct list_head node;96 unsigned char data[NVEC_MSG_SIZE];97 unsigned short size;98 unsigned short pos;99 atomic_t used;100};101 102/**103 * struct nvec_chip - A single connection to an NVIDIA Embedded controller104 * @dev: The device105 * @gpio: The same as for &struct nvec_platform_data106 * @irq: The IRQ of the I2C device107 * @i2c_addr: The address of the I2C slave108 * @base: The base of the memory mapped region of the I2C device109 * @i2c_clk: The clock of the I2C device110 * @rst: The reset of the I2C device111 * @notifier_list: Notifiers to be called on received messages, see112 * nvec_register_notifier()113 * @rx_data: Received messages that have to be processed114 * @tx_data: Messages waiting to be sent to the controller115 * @nvec_status_notifier: Internal notifier (see nvec_status_notifier())116 * @rx_work: A work structure for the RX worker nvec_dispatch()117 * @tx_work: A work structure for the TX worker nvec_request_master()118 * @wq: The work queue in which @rx_work and @tx_work are executed119 * @rx: The message currently being retrieved or %NULL120 * @msg_pool: A pool of messages for allocation121 * @tx: The message currently being transferred122 * @tx_scratch: Used for building pseudo messages123 * @ec_transfer: A completion that will be completed once a message has been124 * received (see nvec_rx_completed())125 * @tx_lock: Spinlock for modifications on @tx_data126 * @rx_lock: Spinlock for modifications on @rx_data127 * @sync_write_mutex: A mutex for nvec_write_sync()128 * @sync_write: A completion to signal that a synchronous message is complete129 * @sync_write_pending: The first two bytes of the request (type and subtype)130 * @last_sync_msg: The last synchronous message.131 * @state: State of our finite state machine used in nvec_interrupt()132 */133struct nvec_chip {134 struct device *dev;135 struct gpio_desc *gpiod;136 int irq;137 u32 i2c_addr;138 void __iomem *base;139 struct clk *i2c_clk;140 struct reset_control *rst;141 struct atomic_notifier_head notifier_list;142 struct list_head rx_data, tx_data;143 struct notifier_block nvec_status_notifier;144 struct work_struct rx_work, tx_work;145 struct workqueue_struct *wq;146 struct nvec_msg msg_pool[NVEC_POOL_SIZE];147 struct nvec_msg *rx;148 149 struct nvec_msg *tx;150 struct nvec_msg tx_scratch;151 struct completion ec_transfer;152 153 spinlock_t tx_lock, rx_lock;154 155 /* sync write stuff */156 struct mutex sync_write_mutex;157 struct completion sync_write;158 u16 sync_write_pending;159 struct nvec_msg *last_sync_msg;160 161 int state;162};163 164int nvec_write_async(struct nvec_chip *nvec, const unsigned char *data,165 short size);166 167int nvec_write_sync(struct nvec_chip *nvec,168 const unsigned char *data, short size,169 struct nvec_msg **msg);170 171int nvec_register_notifier(struct nvec_chip *nvec,172 struct notifier_block *nb,173 unsigned int events);174 175int nvec_unregister_notifier(struct nvec_chip *dev, struct notifier_block *nb);176 177void nvec_msg_free(struct nvec_chip *nvec, struct nvec_msg *msg);178 179#endif180