drivers/staging/nvec/nvec.h

   1 /*
   2  * NVEC: NVIDIA compliant embedded controller interface
   3  *
   4  * Copyright (C) 2011 The AC100 Kernel Team <ac100@lists.launchpad.net>
   5  *
   6  * Authors:  Pierre-Hugues Husson <phhusson@free.fr>
   7  *           Ilya Petrov <ilya.muromec@gmail.com>
   8  *           Marc Dietrich <marvin24@gmx.de>
   9  *           Julian Andres Klode <jak@jak-linux.org>
  10  *
  11  * This file is subject to the terms and conditions of the GNU General Public
  12  * License.  See the file "COPYING" in the main directory of this archive
  13  * for more details.
  14  *
  15  */
  16
  17 #ifndef __LINUX_MFD_NVEC
  18 #define __LINUX_MFD_NVEC
  19
  20 #include <linux/atomic.h>
  21 #include <linux/clk.h>
  22 #include <linux/completion.h>
  23 #include <linux/list.h>
  24 #include <linux/mutex.h>
  25 #include <linux/notifier.h>
  26 #include <linux/reset.h>
  27 #include <linux/spinlock.h>
  28 #include <linux/workqueue.h>
  29
  30 /* NVEC_POOL_SIZE - Size of the pool in &struct nvec_msg */
  31 #define NVEC_POOL_SIZE  64
  32
  33 /*
  34  * NVEC_MSG_SIZE - Maximum size of the data field of &struct nvec_msg.
  35  *
  36  * A message must store up to a SMBus block operation which consists of
  37  * one command byte, one count byte, and up to 32 payload bytes = 34
  38  * byte.
  39  */
  40 #define NVEC_MSG_SIZE   34
  41
  42 /**
  43  * enum nvec_event_size - The size of an event message
  44  * @NVEC_2BYTES: The message has one command byte and one data byte
  45  * @NVEC_3BYTES: The message has one command byte and two data bytes
  46  * @NVEC_VAR_SIZE: The message has one command byte, one count byte, and has
  47  *                 up to as many bytes as the number in the count byte. The
  48  *                 maximum is 32
  49  *
  50  * Events can be fixed or variable sized. This is useless on other message
  51  * types, which are always variable sized.
  52  */
  53 enum nvec_event_size {
  54         NVEC_2BYTES,
  55         NVEC_3BYTES,
  56         NVEC_VAR_SIZE,
  57 };
  58
  59 /**
  60  * enum nvec_msg_type - The type of a message
  61  * @NVEC_SYS: A system request/response
  62  * @NVEC_BAT: A battery request/response
  63  * @NVEC_KBD: A keyboard request/response
  64  * @NVEC_PS2: A mouse request/response
  65  * @NVEC_CNTL: A EC control request/response
  66  * @NVEC_KB_EVT: An event from the keyboard
  67  * @NVEC_PS2_EVT: An event from the mouse
  68  *
  69  * Events can be fixed or variable sized. This is useless on other message
  70  * types, which are always variable sized.
  71  */
  72 enum nvec_msg_type {
  73         NVEC_SYS = 1,
  74         NVEC_BAT,
  75         NVEC_GPIO,
  76         NVEC_SLEEP,
  77         NVEC_KBD,
  78         NVEC_PS2,
  79         NVEC_CNTL,
  80         NVEC_OEM0 = 0x0d,
  81         NVEC_KB_EVT = 0x80,
  82         NVEC_PS2_EVT,
  83 };
  84
  85 /**
  86  * struct nvec_msg - A buffer for a single message
  87  * @node: Messages are part of various lists in a &struct nvec_chip
  88  * @data: The data of the message
  89  * @size: For TX messages, the number of bytes used in @data
  90  * @pos:  For RX messages, the current position to write to. For TX messages,
  91  *        the position to read from.
  92  * @used: Used for the message pool to mark a message as free/allocated.
  93  *
  94  * This structure is used to hold outgoing and incoming messages. Outgoing
  95  * messages have a different format than incoming messages, and that is not
  96  * documented yet.
  97  */
  98 struct nvec_msg {
  99         struct list_head node;
 100         unsigned char data[NVEC_MSG_SIZE];
 101         unsigned short size;
 102         unsigned short pos;
 103         atomic_t used;
 104 };
 105
 106 /**
 107  * struct nvec_chip - A single connection to an NVIDIA Embedded controller
 108  * @dev: The device
 109  * @gpio: The same as for &struct nvec_platform_data
 110  * @irq: The IRQ of the I2C device
 111  * @i2c_addr: The address of the I2C slave
 112  * @base: The base of the memory mapped region of the I2C device
 113  * @i2c_clk: The clock of the I2C device
 114  * @rst: The reset of the I2C device
 115  * @notifier_list: Notifiers to be called on received messages, see
 116  *                 nvec_register_notifier()
 117  * @rx_data: Received messages that have to be processed
 118  * @tx_data: Messages waiting to be sent to the controller
 119  * @nvec_status_notifier: Internal notifier (see nvec_status_notifier())
 120  * @rx_work: A work structure for the RX worker nvec_dispatch()
 121  * @tx_work: A work structure for the TX worker nvec_request_master()
 122  * @wq: The work queue in which @rx_work and @tx_work are executed
 123  * @rx: The message currently being retrieved or %NULL
 124  * @msg_pool: A pool of messages for allocation
 125  * @tx: The message currently being transferred
 126  * @tx_scratch: Used for building pseudo messages
 127  * @ec_transfer: A completion that will be completed once a message has been
 128  *               received (see nvec_rx_completed())
 129  * @tx_lock: Spinlock for modifications on @tx_data
 130  * @rx_lock: Spinlock for modifications on @rx_data
 131  * @sync_write_mutex: A mutex for nvec_write_sync()
 132  * @sync_write: A completion to signal that a synchronous message is complete
 133  * @sync_write_pending: The first two bytes of the request (type and subtype)
 134  * @last_sync_msg: The last synchronous message.
 135  * @state: State of our finite state machine used in nvec_interrupt()
 136  */
 137 struct nvec_chip {
 138         struct device *dev;
 139         int gpio;
 140         int irq;
 141         int i2c_addr;
 142         void __iomem *base;
 143         struct clk *i2c_clk;
 144         struct reset_control *rst;
 145         struct atomic_notifier_head notifier_list;
 146         struct list_head rx_data, tx_data;
 147         struct notifier_block nvec_status_notifier;
 148         struct work_struct rx_work, tx_work;
 149         struct workqueue_struct *wq;
 150         struct nvec_msg msg_pool[NVEC_POOL_SIZE];
 151         struct nvec_msg *rx;
 152
 153         struct nvec_msg *tx;
 154         struct nvec_msg tx_scratch;
 155         struct completion ec_transfer;
 156
 157         spinlock_t tx_lock, rx_lock;
 158
 159         /* sync write stuff */
 160         struct mutex sync_write_mutex;
 161         struct completion sync_write;
 162         u16 sync_write_pending;
 163         struct nvec_msg *last_sync_msg;
 164
 165         int state;
 166 };
 167
 168 int nvec_write_async(struct nvec_chip *nvec, const unsigned char *data,
 169                      short size);
 170
 171 struct nvec_msg *nvec_write_sync(struct nvec_chip *nvec,
 172                                  const unsigned char *data, short size);
 173
 174 int nvec_register_notifier(struct nvec_chip *nvec,
 175                            struct notifier_block *nb,
 176                            unsigned int events);
 177
 178 int nvec_unregister_notifier(struct nvec_chip *dev, struct notifier_block *nb);
 179
 180 void nvec_msg_free(struct nvec_chip *nvec, struct nvec_msg *msg);
 181
 182 #endif