diff options
author | Jonathan Herman <hermanjl@cs.unc.edu> | 2013-01-22 10:38:37 -0500 |
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committer | Jonathan Herman <hermanjl@cs.unc.edu> | 2013-01-22 10:38:37 -0500 |
commit | fcc9d2e5a6c89d22b8b773a64fb4ad21ac318446 (patch) | |
tree | a57612d1888735a2ec7972891b68c1ac5ec8faea /include/linux/i2c-slave.h | |
parent | 8dea78da5cee153b8af9c07a2745f6c55057fe12 (diff) |
Diffstat (limited to 'include/linux/i2c-slave.h')
-rw-r--r-- | include/linux/i2c-slave.h | 259 |
1 files changed, 259 insertions, 0 deletions
diff --git a/include/linux/i2c-slave.h b/include/linux/i2c-slave.h new file mode 100644 index 00000000000..34df64f73f6 --- /dev/null +++ b/include/linux/i2c-slave.h | |||
@@ -0,0 +1,259 @@ | |||
1 | /* | ||
2 | * i2c-slave.h - definitions for the i2c-slave-bus interface | ||
3 | * | ||
4 | * Copyright (c) 2009-2011, NVIDIA Corporation. | ||
5 | * | ||
6 | * This program is free software; you can redistribute it and/or modify | ||
7 | * it under the terms of the GNU General Public License as published by | ||
8 | * the Free Software Foundation; either version 2 of the License, or | ||
9 | * (at your option) any later version. | ||
10 | * | ||
11 | * This program is distributed in the hope that it will be useful, but WITHOUT | ||
12 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or | ||
13 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for | ||
14 | * more details. | ||
15 | * | ||
16 | * You should have received a copy of the GNU General Public License along | ||
17 | * with this program; if not, write to the Free Software Foundation, Inc., | ||
18 | * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. | ||
19 | */ | ||
20 | |||
21 | /* ------------------------------------------------------------------------- */ | ||
22 | |||
23 | #ifndef _LINUX_I2C_SLAVE_H | ||
24 | #define _LINUX_I2C_SLAVE_H | ||
25 | |||
26 | #include <linux/types.h> | ||
27 | #ifdef __KERNEL__ | ||
28 | /* --- General options ------------------------------------------------ */ | ||
29 | |||
30 | struct i2c_client; | ||
31 | struct i2c_slave_algorithm; | ||
32 | struct i2c_slave_adapter; | ||
33 | #if defined(CONFIG_I2C_SLAVE) && defined(CONFIG_I2C) | ||
34 | |||
35 | /** | ||
36 | * i2c_slave_send - Sends data to master. When master issues a read cycle, the | ||
37 | * data is sent by the slave. | ||
38 | * This function copies the client data into the slave tx buffer and return to | ||
39 | * client. This is not a blocking call. Data will be sent to master later once | ||
40 | * slave got the master-ready cycle transfer. | ||
41 | * if there is no sufficient space to write the client buffer, it will return | ||
42 | * error. it will not write partial data. | ||
43 | * @client: Handle to i2c-slave client. | ||
44 | * @buf: Data that will be written to the master | ||
45 | * @count: How many bytes to write. | ||
46 | * | ||
47 | * Returns negative errno, or else the number of bytes written. | ||
48 | */ | ||
49 | extern int i2c_slave_send(struct i2c_client *client, const char *buf, | ||
50 | int count); | ||
51 | |||
52 | /** | ||
53 | * i2c_slave_get_tx_status - Get amount of data available in tx buffer. If there | ||
54 | * is still data in tx buffer then wait for given time to transfer complete | ||
55 | * for a give timeout. | ||
56 | * @client: Handle to i2c-slave client. | ||
57 | * @timeout_ms: Time to wait for transfer to complete. | ||
58 | * | ||
59 | * Returns negative errno, or else the number of bytes remaining in tx buffer. | ||
60 | */ | ||
61 | extern int i2c_slave_get_tx_status(struct i2c_client *client, int timeout_ms); | ||
62 | |||
63 | /** | ||
64 | * i2c_slave_recv - Receive data from master. The data received from master is | ||
65 | * stored on slave rx buffer. When this api will be called, the data will be | ||
66 | * copied from the slave rx buffer to client buffer. If requested amount (count) | ||
67 | * of data is not available then it will wait for either min_count to be receive | ||
68 | * or timeout whatever first. | ||
69 | * | ||
70 | * if timeout_ms = 0, then wait for min_count data to be read. | ||
71 | * if timoue_ms non zero then wait for the data till timeout happen. | ||
72 | * @client: Handle to i2c-slave client. | ||
73 | * @buf: Data that will be read from the master | ||
74 | * @count: How many bytes to read. | ||
75 | * @min_count: Block till read min_count of data. | ||
76 | * @timeout_ms: Time to wait for read to be complete. | ||
77 | * | ||
78 | * Returns negative errno, or else the number of bytes read. | ||
79 | */ | ||
80 | extern int i2c_slave_recv(struct i2c_client *client, char *buf, int count, | ||
81 | int min_count, int timeout_ms); | ||
82 | |||
83 | /** | ||
84 | * i2c_slave_start - Start the i2c slave to receive/transmit data. | ||
85 | * After this i2c controller starts responding master. | ||
86 | * The dummy-char will send to master if there is no data to send on slave tx | ||
87 | * buffer. | ||
88 | * @client: Handle to i2c-slave client. | ||
89 | * @dummy_char: Data which will be send to master if there is no data to be send | ||
90 | * in slave tx buffer. | ||
91 | * | ||
92 | * Returns negative errno, or else 0 for success. | ||
93 | */ | ||
94 | extern int i2c_slave_start(struct i2c_client *client, unsigned char dummy_char); | ||
95 | |||
96 | /** | ||
97 | * i2c_slave_stop - Stop slave to receive/transmit data. | ||
98 | * After this i2c controller stops responding master. | ||
99 | * @client: Handle to i2c-slave client. | ||
100 | * @is_buffer_clear: Reset the tx and rx slave buffer or not. | ||
101 | */ | ||
102 | extern void i2c_slave_stop(struct i2c_client *client, int is_buffer_clear); | ||
103 | |||
104 | /** | ||
105 | * i2c_slave_flush_buffer - Flush the receive and transmit buffer. | ||
106 | * @client: Handle to i2c-slave client. | ||
107 | * @is_flush_tx_buffer: Reset the tx slave buffer or not. | ||
108 | * @is_flush_rx_buffer: Reset the rx slave buffer or not. | ||
109 | * | ||
110 | * Returns negative errno, or else 0 for success. | ||
111 | */ | ||
112 | extern int i2c_slave_flush_buffer(struct i2c_client *client, | ||
113 | int is_flush_tx_buffer, int is_flush_rx_buffer); | ||
114 | |||
115 | /** | ||
116 | * i2c_slave_get_nack_cycle - Get the number of master read cycle on which | ||
117 | * dummy char sent. This is the way to find that how much cycle slave sent the | ||
118 | * NACK packet. | ||
119 | * | ||
120 | * @client: Handle to i2c-slave client. | ||
121 | * @is_cout_reset: Reset the nack count or not. | ||
122 | * | ||
123 | * Returns negative errno, or else 0 for success. | ||
124 | */ | ||
125 | extern int i2c_slave_get_nack_cycle(struct i2c_client *client, | ||
126 | int is_cout_reset); | ||
127 | |||
128 | |||
129 | /** | ||
130 | * i2c_add_slave_adapter - Add slave adapter. | ||
131 | * | ||
132 | * @slv_adap: Slave adapter. | ||
133 | * @force_nr: Adapter number. | ||
134 | * | ||
135 | * Returns negative errno, or else 0 for success. | ||
136 | */ | ||
137 | extern int i2c_add_slave_adapter(struct i2c_slave_adapter *slv_adap, | ||
138 | bool force_nr); | ||
139 | |||
140 | /** | ||
141 | * i2c_del_slave_adapter - Delete slave adapter. | ||
142 | * | ||
143 | * @slv_adap: Slave adapter. | ||
144 | * | ||
145 | * Returns negative errno, or else 0 for success. | ||
146 | */ | ||
147 | extern int i2c_del_slave_adapter(struct i2c_slave_adapter *slv_adap); | ||
148 | |||
149 | #endif /* I2C_SLAVE */ | ||
150 | |||
151 | /* | ||
152 | * i2c_slave_adapter is the structure used to identify a physical i2c bus along | ||
153 | * with the access algorithms necessary to access it. | ||
154 | */ | ||
155 | struct i2c_slave_adapter { | ||
156 | struct module *owner; | ||
157 | unsigned int id; | ||
158 | unsigned int class; /* classes to allow probing for */ | ||
159 | /* the algorithm to access the i2c-slave bus */ | ||
160 | const struct i2c_slave_algorithm *slv_algo; | ||
161 | void *algo_data; | ||
162 | void *parent_data; | ||
163 | |||
164 | /* data fields that are valid for all devices */ | ||
165 | u8 level; /* nesting level for lockdep */ | ||
166 | struct mutex bus_lock; | ||
167 | |||
168 | int timeout; /* in jiffies */ | ||
169 | int retries; | ||
170 | struct device *dev; /* the adapter device */ | ||
171 | struct device *parent_dev; /* the adapter device */ | ||
172 | |||
173 | int nr; | ||
174 | char name[48]; | ||
175 | struct completion dev_released; | ||
176 | }; | ||
177 | |||
178 | static inline void *i2c_get_slave_adapdata(const struct i2c_slave_adapter *dev) | ||
179 | { | ||
180 | return dev_get_drvdata(dev->dev); | ||
181 | } | ||
182 | |||
183 | static inline void i2c_set_slave_adapdata(struct i2c_slave_adapter *dev, | ||
184 | void *data) | ||
185 | { | ||
186 | dev_set_drvdata(dev->dev, data); | ||
187 | } | ||
188 | |||
189 | /* | ||
190 | * The following struct are for those who like to implement new i2c slave | ||
191 | * bus drivers: | ||
192 | * i2c_slave_algorithm is the interface to a class of hardware solutions which | ||
193 | * can be addressed using the same bus algorithms. | ||
194 | */ | ||
195 | struct i2c_slave_algorithm { | ||
196 | /* Start the slave to receive/transmit data. | ||
197 | * The dummy-char will send to master if there is no data to send on | ||
198 | * slave tx buffer. | ||
199 | */ | ||
200 | int (*slave_start)(struct i2c_slave_adapter *slv_adap, int addr, | ||
201 | int is_ten_bit_addr, unsigned char dummy_char); | ||
202 | |||
203 | /* Stop slave to receive/transmit data. | ||
204 | * Required information to reset the slave rx and tx buffer to reset | ||
205 | * or not. | ||
206 | */ | ||
207 | void (*slave_stop)(struct i2c_slave_adapter *slv_adap, | ||
208 | int is_buffer_clear); | ||
209 | |||
210 | /* | ||
211 | * Send data to master. The data will be copied on the slave tx buffer | ||
212 | * and will send to master once master initiates the master-read cycle. | ||
213 | * Function will return immediately once the buffer copied into slave | ||
214 | * tx buffer. | ||
215 | * Client will not wait till data is sent to master. | ||
216 | * This function will not copy data partially. If sufficient space is | ||
217 | * not available, it will return error. | ||
218 | */ | ||
219 | int (*slave_send)(struct i2c_slave_adapter *slv_adap, const char *buf, | ||
220 | int count); | ||
221 | |||
222 | /* | ||
223 | * Get amount of data available in tx buffer. If there is still data in | ||
224 | * tx buffer wait for given time to get slave tx buffer emptied. | ||
225 | * returns number of data available in slave tx buffer. | ||
226 | */ | ||
227 | int (*slave_get_tx_status)(struct i2c_slave_adapter *slv_adap, | ||
228 | int timeout_ms); | ||
229 | |||
230 | /* | ||
231 | * Receive data to master. The data received from master is stored on | ||
232 | * slave rx buffer. When this api will be called, the data will be | ||
233 | * coped from the slave rx buffer to client buffer. If requested (count) | ||
234 | * data is not available then it will wait for either min_count to be | ||
235 | * receive or timeout whatever first. | ||
236 | * | ||
237 | * if timeout_ms = 0, then wait for min_count data to be read. | ||
238 | * if timoue_ms non zero then wait for the data till timeout happen. | ||
239 | * returns number of bytes read as positive integer otherwise error. | ||
240 | */ | ||
241 | int (*slave_recv)(struct i2c_slave_adapter *slv_adap, char *buf, | ||
242 | int count, int min_count, int timeout_ms); | ||
243 | |||
244 | /* Flush the receive and transmit buffer. | ||
245 | */ | ||
246 | int (*slave_flush_buffer)(struct i2c_slave_adapter *slv_adap, | ||
247 | int is_flush_tx_buffer, int is_flush_rx_buffer); | ||
248 | |||
249 | /* Get the number of dummy char cycle. | ||
250 | * Get the number of master read cycle on which dummy character has | ||
251 | * been sent. | ||
252 | * This can be treat as NACK cycle from slave side. | ||
253 | * Pass option whether count need to be reset or not. | ||
254 | */ | ||
255 | int (*slave_get_nack_cycle)(struct i2c_slave_adapter *slv_adap, | ||
256 | int is_cout_reset); | ||
257 | }; | ||
258 | #endif /* __KERNEL__ */ | ||
259 | #endif /* _LINUX_I2C_SLAVE_H */ | ||