diff options
Diffstat (limited to 'firmware/target/mips/ingenic_jz47xx/i2c-jz4740.c')
-rw-r--r-- | firmware/target/mips/ingenic_jz47xx/i2c-jz4740.c | 240 |
1 files changed, 240 insertions, 0 deletions
diff --git a/firmware/target/mips/ingenic_jz47xx/i2c-jz4740.c b/firmware/target/mips/ingenic_jz47xx/i2c-jz4740.c new file mode 100644 index 0000000000..1fbf1fc19e --- /dev/null +++ b/firmware/target/mips/ingenic_jz47xx/i2c-jz4740.c | |||
@@ -0,0 +1,240 @@ | |||
1 | /*************************************************************************** | ||
2 | * __________ __ ___. | ||
3 | * Open \______ \ ____ ____ | | _\_ |__ _______ ___ | ||
4 | * Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ / | ||
5 | * Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < < | ||
6 | * Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \ | ||
7 | * \/ \/ \/ \/ \/ | ||
8 | * $Id$ | ||
9 | * | ||
10 | * Copyright (C) 2009 by Maurus Cuelenaere | ||
11 | * | ||
12 | * based on linux/arch/mips/jz4740/i2c.c | ||
13 | * | ||
14 | * This program is free software; you can redistribute it and/or | ||
15 | * modify it under the terms of the GNU General Public License | ||
16 | * as published by the Free Software Foundation; either version 2 | ||
17 | * of the License, or (at your option) any later version. | ||
18 | * | ||
19 | * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY | ||
20 | * KIND, either express or implied. | ||
21 | * | ||
22 | ****************************************************************************/ | ||
23 | |||
24 | /* | ||
25 | * Jz4740 I2C routines. | ||
26 | * | ||
27 | * Copyright (C) 2005,2006 Ingenic Semiconductor Inc. | ||
28 | * Author: <lhhuang@ingenic.cn> | ||
29 | * | ||
30 | * This program is free software; you can distribute it and/or modify it | ||
31 | * under the terms of the GNU General Public License (Version 2) as | ||
32 | * published by the Free Software Foundation. | ||
33 | * | ||
34 | * This program is distributed in the hope it will be useful, but WITHOUT | ||
35 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or | ||
36 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License | ||
37 | * for more details. | ||
38 | * | ||
39 | * You should have received a copy of the GNU General Public License along | ||
40 | * with this program; if not, write to the Free Software Foundation, Inc., | ||
41 | * 59 Temple Place - Suite 330, Boston MA 02111-1307, USA. | ||
42 | * | ||
43 | */ | ||
44 | |||
45 | #include "config.h" | ||
46 | #include "system.h" | ||
47 | #include "jz4740.h" | ||
48 | #include "logf.h" | ||
49 | #include "generic_i2c.h" | ||
50 | |||
51 | |||
52 | /* I2C protocol */ | ||
53 | #define I2C_READ 1 | ||
54 | #define I2C_WRITE 0 | ||
55 | |||
56 | #define TIMEOUT 1000 | ||
57 | |||
58 | /* | ||
59 | * I2C bus protocol basic routines | ||
60 | */ | ||
61 | static int i2c_put_data(unsigned char data) | ||
62 | { | ||
63 | unsigned int timeout = TIMEOUT*10; | ||
64 | |||
65 | __i2c_write(data); | ||
66 | __i2c_set_drf(); | ||
67 | while (__i2c_check_drf() != 0); | ||
68 | while (!__i2c_transmit_ended()); | ||
69 | while (!__i2c_received_ack() && timeout) | ||
70 | timeout--; | ||
71 | |||
72 | if (timeout) | ||
73 | return 0; | ||
74 | else | ||
75 | return -1; | ||
76 | } | ||
77 | |||
78 | static int i2c_put_data_nack(unsigned char data) | ||
79 | { | ||
80 | unsigned int timeout = TIMEOUT*10; | ||
81 | |||
82 | __i2c_write(data); | ||
83 | __i2c_set_drf(); | ||
84 | while (__i2c_check_drf() != 0); | ||
85 | while (!__i2c_transmit_ended()); | ||
86 | while (timeout--); | ||
87 | |||
88 | return 0; | ||
89 | } | ||
90 | |||
91 | static int i2c_get_data(unsigned char *data, int ack) | ||
92 | { | ||
93 | int timeout = TIMEOUT*10; | ||
94 | |||
95 | if (!ack) | ||
96 | __i2c_send_nack(); | ||
97 | else | ||
98 | __i2c_send_ack(); | ||
99 | |||
100 | while (__i2c_check_drf() == 0 && timeout) | ||
101 | timeout--; | ||
102 | |||
103 | if (timeout) | ||
104 | { | ||
105 | if (!ack) | ||
106 | __i2c_send_stop(); | ||
107 | *data = __i2c_read(); | ||
108 | __i2c_clear_drf(); | ||
109 | return 0; | ||
110 | } | ||
111 | else | ||
112 | return -1; | ||
113 | } | ||
114 | |||
115 | /* | ||
116 | * I2C interface | ||
117 | */ | ||
118 | void i2c_open(void) | ||
119 | { | ||
120 | /* TODO */ | ||
121 | //__i2c_set_clk(jz_clocks.extalclk, 10000); /* default 10 KHz */ | ||
122 | __i2c_enable(); | ||
123 | } | ||
124 | |||
125 | void i2c_close(void) | ||
126 | { | ||
127 | udelay(300); /* wait for STOP goes over. */ | ||
128 | __i2c_disable(); | ||
129 | } | ||
130 | |||
131 | void i2c_setclk(unsigned int i2cclk) | ||
132 | { | ||
133 | /* TODO */ | ||
134 | //__i2c_set_clk(jz_clocks.extalclk, i2cclk); | ||
135 | } | ||
136 | |||
137 | int i2c_read(int device, unsigned char *buf, int count) | ||
138 | { | ||
139 | int cnt = count; | ||
140 | int timeout = 5; | ||
141 | |||
142 | device &= 0xFF; | ||
143 | |||
144 | L_try_again: | ||
145 | if (timeout < 0) | ||
146 | goto L_timeout; | ||
147 | |||
148 | __i2c_send_nack(); /* Master does not send ACK, slave sends it */ | ||
149 | |||
150 | __i2c_send_start(); | ||
151 | if (i2c_put_data( (device << 1) | I2C_READ ) < 0) | ||
152 | goto device_err; | ||
153 | |||
154 | __i2c_send_ack(); /* Master sends ACK for continue reading */ | ||
155 | |||
156 | while (cnt) | ||
157 | { | ||
158 | if (cnt == 1) | ||
159 | { | ||
160 | if (i2c_get_data(buf, 0) < 0) | ||
161 | break; | ||
162 | } | ||
163 | else | ||
164 | { | ||
165 | if (i2c_get_data(buf, 1) < 0) | ||
166 | break; | ||
167 | } | ||
168 | cnt--; | ||
169 | buf++; | ||
170 | } | ||
171 | |||
172 | __i2c_send_stop(); | ||
173 | return count - cnt; | ||
174 | |||
175 | device_err: | ||
176 | timeout--; | ||
177 | __i2c_send_stop(); | ||
178 | goto L_try_again; | ||
179 | |||
180 | L_timeout: | ||
181 | __i2c_send_stop(); | ||
182 | logf("Read I2C device 0x%2x failed.", device); | ||
183 | return -1; | ||
184 | } | ||
185 | |||
186 | int i2c_write(int device, unsigned char *buf, int count) | ||
187 | { | ||
188 | int cnt = count; | ||
189 | int timeout = 5; | ||
190 | |||
191 | device &= 0xFF; | ||
192 | |||
193 | __i2c_send_nack(); /* Master does not send ACK, slave sends it */ | ||
194 | |||
195 | W_try_again: | ||
196 | if (timeout < 0) | ||
197 | goto W_timeout; | ||
198 | |||
199 | cnt = count; | ||
200 | |||
201 | __i2c_send_start(); | ||
202 | if (i2c_put_data( (device << 1) | I2C_WRITE ) < 0) | ||
203 | goto device_err; | ||
204 | |||
205 | #if 0 //CONFIG_JZ_TPANEL_ATA2508 | ||
206 | if (address == 0xff) | ||
207 | { | ||
208 | while (cnt) | ||
209 | { | ||
210 | if (i2c_put_data_nack(*buf) < 0) | ||
211 | break; | ||
212 | cnt--; | ||
213 | buf++; | ||
214 | } | ||
215 | } | ||
216 | else | ||
217 | #endif | ||
218 | { | ||
219 | while (cnt) | ||
220 | { | ||
221 | if (i2c_put_data(*buf) < 0) | ||
222 | break; | ||
223 | cnt--; | ||
224 | buf++; | ||
225 | } | ||
226 | } | ||
227 | |||
228 | __i2c_send_stop(); | ||
229 | return count - cnt; | ||
230 | |||
231 | device_err: | ||
232 | timeout--; | ||
233 | __i2c_send_stop(); | ||
234 | goto W_try_again; | ||
235 | |||
236 | W_timeout: | ||
237 | logf("Write I2C device 0x%2x failed.", device); | ||
238 | __i2c_send_stop(); | ||
239 | return -1; | ||
240 | } | ||