• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
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 int nvec_write_sync(struct nvec_chip *nvec,
172 		    const unsigned char *data, short size,
173 		    struct nvec_msg **msg);
174 
175 int nvec_register_notifier(struct nvec_chip *nvec,
176 			   struct notifier_block *nb,
177 			   unsigned int events);
178 
179 int nvec_unregister_notifier(struct nvec_chip *dev, struct notifier_block *nb);
180 
181 void nvec_msg_free(struct nvec_chip *nvec, struct nvec_msg *msg);
182 
183 #endif
184