2 * ChromeOS EC multi-function device
4 * Copyright (C) 2012 Google, Inc
6 * This software is licensed under the terms of the GNU General Public
7 * License version 2, as published by the Free Software Foundation, and
8 * may be copied, distributed, and modified under those terms.
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
16 #ifndef __LINUX_MFD_CROS_EC_H
17 #define __LINUX_MFD_CROS_EC_H
19 #include <linux/notifier.h>
20 #include <linux/mfd/cros_ec_commands.h>
21 #include <linux/mutex.h>
24 * Command interface between EC and AP, for LPC, I2C and SPI interfaces.
27 EC_MSG_TX_HEADER_BYTES = 3,
28 EC_MSG_TX_TRAILER_BYTES = 1,
29 EC_MSG_TX_PROTO_BYTES = EC_MSG_TX_HEADER_BYTES +
30 EC_MSG_TX_TRAILER_BYTES,
31 EC_MSG_RX_PROTO_BYTES = 3,
33 /* Max length of messages */
34 EC_MSG_BYTES = EC_PROTO2_MAX_PARAM_SIZE +
35 EC_MSG_TX_PROTO_BYTES,
39 * @version: Command version number (often 0)
40 * @command: Command to send (EC_CMD_...)
41 * @outdata: Outgoing data to EC
42 * @outsize: Outgoing length in bytes
43 * @indata: Where to put the incoming data from EC
44 * @insize: Incoming length in bytes (filled in by EC)
45 * @result: EC's response to the command (separate from communication failure)
47 struct cros_ec_command {
58 * struct cros_ec_device - Information about a ChromeOS EC device
60 * @ec_name: name of EC device (e.g. 'chromeos-ec')
61 * @phys_name: name of physical comms layer (e.g. 'i2c-4')
62 * @dev: Device pointer
63 * @was_wake_device: true if this device was set to wake the system from
64 * sleep at the last suspend
65 * @event_notifier: interrupt event notifier for transport devices
66 * @command_send: send a command
67 * @command_recv: receive a response
68 * @command_sendrecv: send a command and receive a response
70 * @name: Name of this EC interface
72 * @irq: Interrupt to use
73 * @din: input buffer (for data from EC)
74 * @dout: output buffer (for data to EC)
76 * These two buffers will always be dword-aligned and include enough
77 * space for up to 7 word-alignment bytes also, so we can ensure that
78 * the body of the message is always dword-aligned (64-bit).
79 * We use this alignment to keep ARM and x86 happy. Probably word
80 * alignment would be OK, there might be a small performance advantage
82 * @din_size: size of din buffer to allocate (zero to use static din)
83 * @dout_size: size of dout buffer to allocate (zero to use static dout)
84 * @parent: pointer to parent device (e.g. i2c or spi device)
85 * @wake_enabled: true if this device can wake the system from sleep
86 * @lock: one transaction at a time
87 * @cmd_xfer: low-level channel to the EC
89 struct cros_ec_device {
91 /* These are used by other drivers that want to talk to the EC */
93 const char *phys_name;
96 struct class *cros_class;
97 struct blocking_notifier_head event_notifier;
98 int (*command_send)(struct cros_ec_device *ec,
99 uint16_t cmd, void *out_buf, int out_len);
100 int (*command_recv)(struct cros_ec_device *ec,
101 uint16_t cmd, void *in_buf, int in_len);
102 int (*command_sendrecv)(struct cros_ec_device *ec,
103 uint16_t cmd, void *out_buf, int out_len,
104 void *in_buf, int in_len);
106 /* These are used to implement the platform-specific interface */
114 struct device *parent;
117 int (*cmd_xfer)(struct cros_ec_device *ec,
118 struct cros_ec_command *msg);
122 * cros_ec_suspend - Handle a suspend operation for the ChromeOS EC device
124 * This can be called by drivers to handle a suspend event.
126 * ec_dev: Device to suspend
127 * @return 0 if ok, -ve on error
129 int cros_ec_suspend(struct cros_ec_device *ec_dev);
132 * cros_ec_resume - Handle a resume operation for the ChromeOS EC device
134 * This can be called by drivers to handle a resume event.
136 * @ec_dev: Device to resume
137 * @return 0 if ok, -ve on error
139 int cros_ec_resume(struct cros_ec_device *ec_dev);
142 * cros_ec_prepare_tx - Prepare an outgoing message in the output buffer
144 * This is intended to be used by all ChromeOS EC drivers, but at present
145 * only SPI uses it. Once LPC uses the same protocol it can start using it.
146 * I2C could use it now, with a refactor of the existing code.
148 * @ec_dev: Device to register
149 * @msg: Message to write
151 int cros_ec_prepare_tx(struct cros_ec_device *ec_dev,
152 struct cros_ec_command *msg);
155 * cros_ec_remove - Remove a ChromeOS EC
157 * Call this to deregister a ChromeOS EC, then clean up any private data.
159 * @ec_dev: Device to register
160 * @return 0 if ok, -ve on error
162 int cros_ec_remove(struct cros_ec_device *ec_dev);
165 * cros_ec_register - Register a new ChromeOS EC, using the provided info
167 * Before calling this, allocate a pointer to a new device and then fill
168 * in all the fields up to the --private-- marker.
170 * @ec_dev: Device to register
171 * @return 0 if ok, -ve on error
173 int cros_ec_register(struct cros_ec_device *ec_dev);
175 #endif /* __LINUX_MFD_CROS_EC_H */