1/* SPDX-License-Identifier: GPL-2.0 */ 2/* 3 * NVEC: NVIDIA compliant embedded controller interface 4 * 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_NVEC 14#define __LINUX_MFD_NVEC 15 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 64 28 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 of 33 * one command byte, one count byte, and up to 32 payload bytes = 34 34 * byte. 35 */ 36#define NVEC_MSG_SIZE 34 37 38/** 39 * enum nvec_event_size - The size of an event message 40 * @NVEC_2BYTES: The message has one command byte and one data byte 41 * @NVEC_3BYTES: The message has one command byte and two data bytes 42 * @NVEC_VAR_SIZE: The message has one command byte, one count byte, and has 43 * up to as many bytes as the number in the count byte. The 44 * maximum is 32 45 * 46 * Events can be fixed or variable sized. This is useless on other message 47 * 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 message 57 * @NVEC_SYS: A system request/response 58 * @NVEC_BAT: A battery request/response 59 * @NVEC_KBD: A keyboard request/response 60 * @NVEC_PS2: A mouse request/response 61 * @NVEC_CNTL: A EC control request/response 62 * @NVEC_KB_EVT: An event from the keyboard 63 * @NVEC_PS2_EVT: An event from the mouse 64 * 65 * Events can be fixed or variable sized. This is useless on other message 66 * 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 message 83 * @node: Messages are part of various lists in a &struct nvec_chip 84 * @data: The data of the message 85 * @size: For TX messages, the number of bytes used in @data 86 * @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. Outgoing 91 * messages have a different format than incoming messages, and that is not 92 * 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 controller 104 * @dev: The device 105 * @gpio: The same as for &struct nvec_platform_data 106 * @irq: The IRQ of the I2C device 107 * @i2c_addr: The address of the I2C slave 108 * @base: The base of the memory mapped region of the I2C device 109 * @i2c_clk: The clock of the I2C device 110 * @rst: The reset of the I2C device 111 * @notifier_list: Notifiers to be called on received messages, see 112 * nvec_register_notifier() 113 * @rx_data: Received messages that have to be processed 114 * @tx_data: Messages waiting to be sent to the controller 115 * @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 executed 119 * @rx: The message currently being retrieved or %NULL 120 * @msg_pool: A pool of messages for allocation 121 * @tx: The message currently being transferred 122 * @tx_scratch: Used for building pseudo messages 123 * @ec_transfer: A completion that will be completed once a message has been 124 * received (see nvec_rx_completed()) 125 * @tx_lock: Spinlock for modifications on @tx_data 126 * @rx_lock: Spinlock for modifications on @rx_data 127 * @sync_write_mutex: A mutex for nvec_write_sync() 128 * @sync_write: A completion to signal that a synchronous message is complete 129 * @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#endif 180