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81dee67e SM |
1 | #define USE_HW_I2C |
2 | #ifdef USE_HW_I2C | |
3 | #include "ddk750_help.h" | |
4 | #include "ddk750_reg.h" | |
5 | #include "ddk750_hwi2c.h" | |
6 | #include "ddk750_power.h" | |
7 | ||
8 | #define MAX_HWI2C_FIFO 16 | |
9 | #define HWI2C_WAIT_TIMEOUT 0xF0000 | |
10 | ||
11 | ||
12 | int hwI2CInit( | |
13 | unsigned char busSpeedMode | |
14 | ) | |
15 | { | |
16 | unsigned int value; | |
17 | ||
18 | /* Enable GPIO 30 & 31 as IIC clock & data */ | |
19 | value = PEEK32(GPIO_MUX); | |
20 | ||
21 | value = FIELD_SET(value, GPIO_MUX, 30, I2C) | | |
22 | FIELD_SET(0, GPIO_MUX, 31, I2C); | |
23 | POKE32(GPIO_MUX, value); | |
24 | ||
25 | /* Enable Hardware I2C power. | |
26 | TODO: Check if we need to enable GPIO power? | |
27 | */ | |
28 | enableI2C(1); | |
29 | ||
30 | /* Enable the I2C Controller and set the bus speed mode */ | |
31 | value = PEEK32(I2C_CTRL); | |
32 | if (busSpeedMode == 0) | |
33 | value = FIELD_SET(value, I2C_CTRL, MODE, STANDARD); | |
34 | else | |
35 | value = FIELD_SET(value, I2C_CTRL, MODE, FAST); | |
36 | value = FIELD_SET(value, I2C_CTRL, EN, ENABLE); | |
37 | POKE32(I2C_CTRL, value); | |
38 | ||
39 | return 0; | |
40 | } | |
41 | ||
42 | ||
43 | void hwI2CClose(void) | |
44 | { | |
45 | unsigned int value; | |
46 | ||
47 | /* Disable I2C controller */ | |
48 | value = PEEK32(I2C_CTRL); | |
49 | value = FIELD_SET(value, I2C_CTRL, EN, DISABLE); | |
50 | POKE32(I2C_CTRL, value); | |
51 | ||
52 | /* Disable I2C Power */ | |
53 | enableI2C(0); | |
54 | ||
55 | /* Set GPIO 30 & 31 back as GPIO pins */ | |
56 | value = PEEK32(GPIO_MUX); | |
57 | value = FIELD_SET(value, GPIO_MUX, 30, GPIO); | |
58 | value = FIELD_SET(value, GPIO_MUX, 31, GPIO); | |
59 | POKE32(GPIO_MUX, value); | |
60 | } | |
61 | ||
62 | ||
d93abd15 | 63 | static long hwI2CWaitTXDone(void) |
81dee67e SM |
64 | { |
65 | unsigned int timeout; | |
66 | ||
67 | /* Wait until the transfer is completed. */ | |
68 | timeout = HWI2C_WAIT_TIMEOUT; | |
69 | while ((FIELD_GET(PEEK32(I2C_STATUS), I2C_STATUS, TX) != I2C_STATUS_TX_COMPLETED) && | |
70 | (timeout != 0)) | |
71 | timeout--; | |
72 | ||
73 | if (timeout == 0) | |
74 | return (-1); | |
75 | ||
76 | return 0; | |
77 | } | |
78 | ||
79 | ||
80 | ||
81 | /* | |
82 | * This function writes data to the i2c slave device registers. | |
83 | * | |
84 | * Parameters: | |
85 | * deviceAddress - i2c Slave device address | |
86 | * length - Total number of bytes to be written to the device | |
87 | * pBuffer - The buffer that contains the data to be written to the | |
88 | * i2c device. | |
89 | * | |
90 | * Return Value: | |
91 | * Total number of bytes those are actually written. | |
92 | */ | |
d93abd15 | 93 | static unsigned int hwI2CWriteData( |
81dee67e SM |
94 | unsigned char deviceAddress, |
95 | unsigned int length, | |
96 | unsigned char *pBuffer | |
97 | ) | |
98 | { | |
99 | unsigned char count, i; | |
100 | unsigned int totalBytes = 0; | |
101 | ||
102 | /* Set the Device Address */ | |
103 | POKE32(I2C_SLAVE_ADDRESS, deviceAddress & ~0x01); | |
104 | ||
105 | /* Write data. | |
106 | * Note: | |
107 | * Only 16 byte can be accessed per i2c start instruction. | |
108 | */ | |
109 | do | |
110 | { | |
111 | /* Reset I2C by writing 0 to I2C_RESET register to clear the previous status. */ | |
112 | POKE32(I2C_RESET, 0); | |
113 | ||
114 | /* Set the number of bytes to be written */ | |
115 | if (length < MAX_HWI2C_FIFO) | |
116 | count = length - 1; | |
117 | else | |
118 | count = MAX_HWI2C_FIFO - 1; | |
119 | POKE32(I2C_BYTE_COUNT, count); | |
120 | ||
121 | /* Move the data to the I2C data register */ | |
122 | for (i = 0; i <= count; i++) | |
123 | POKE32(I2C_DATA0 + i, *pBuffer++); | |
124 | ||
125 | /* Start the I2C */ | |
126 | POKE32(I2C_CTRL, FIELD_SET(PEEK32(I2C_CTRL), I2C_CTRL, CTRL, START)); | |
127 | ||
128 | /* Wait until the transfer is completed. */ | |
129 | if (hwI2CWaitTXDone() != 0) | |
130 | break; | |
131 | ||
132 | /* Substract length */ | |
133 | length -= (count + 1); | |
134 | ||
135 | /* Total byte written */ | |
136 | totalBytes += (count + 1); | |
137 | ||
138 | } while (length > 0); | |
139 | ||
140 | return totalBytes; | |
141 | } | |
142 | ||
143 | ||
144 | ||
145 | ||
146 | /* | |
147 | * This function reads data from the slave device and stores them | |
148 | * in the given buffer | |
149 | * | |
150 | * Parameters: | |
151 | * deviceAddress - i2c Slave device address | |
152 | * length - Total number of bytes to be read | |
153 | * pBuffer - Pointer to a buffer to be filled with the data read | |
154 | * from the slave device. It has to be the same size as the | |
155 | * length to make sure that it can keep all the data read. | |
156 | * | |
157 | * Return Value: | |
158 | * Total number of actual bytes read from the slave device | |
159 | */ | |
d93abd15 | 160 | static unsigned int hwI2CReadData( |
81dee67e SM |
161 | unsigned char deviceAddress, |
162 | unsigned int length, | |
163 | unsigned char *pBuffer | |
164 | ) | |
165 | { | |
166 | unsigned char count, i; | |
167 | unsigned int totalBytes = 0; | |
168 | ||
169 | /* Set the Device Address */ | |
170 | POKE32(I2C_SLAVE_ADDRESS, deviceAddress | 0x01); | |
171 | ||
172 | /* Read data and save them to the buffer. | |
173 | * Note: | |
174 | * Only 16 byte can be accessed per i2c start instruction. | |
175 | */ | |
176 | do | |
177 | { | |
178 | /* Reset I2C by writing 0 to I2C_RESET register to clear all the status. */ | |
179 | POKE32(I2C_RESET, 0); | |
180 | ||
181 | /* Set the number of bytes to be read */ | |
182 | if (length <= MAX_HWI2C_FIFO) | |
183 | count = length - 1; | |
184 | else | |
185 | count = MAX_HWI2C_FIFO - 1; | |
186 | POKE32(I2C_BYTE_COUNT, count); | |
187 | ||
188 | /* Start the I2C */ | |
189 | POKE32(I2C_CTRL, FIELD_SET(PEEK32(I2C_CTRL), I2C_CTRL, CTRL, START)); | |
190 | ||
191 | /* Wait until transaction done. */ | |
192 | if (hwI2CWaitTXDone() != 0) | |
193 | break; | |
194 | ||
195 | /* Save the data to the given buffer */ | |
196 | for (i = 0; i <= count; i++) | |
197 | *pBuffer++ = PEEK32(I2C_DATA0 + i); | |
198 | ||
199 | /* Substract length by 16 */ | |
200 | length -= (count + 1); | |
201 | ||
202 | /* Number of bytes read. */ | |
203 | totalBytes += (count + 1); | |
204 | ||
205 | } while (length > 0); | |
206 | ||
207 | return totalBytes; | |
208 | } | |
209 | ||
210 | ||
211 | ||
212 | ||
213 | /* | |
214 | * This function reads the slave device's register | |
215 | * | |
216 | * Parameters: | |
217 | * deviceAddress - i2c Slave device address which register | |
218 | * to be read from | |
219 | * registerIndex - Slave device's register to be read | |
220 | * | |
221 | * Return Value: | |
222 | * Register value | |
223 | */ | |
224 | unsigned char hwI2CReadReg( | |
225 | unsigned char deviceAddress, | |
226 | unsigned char registerIndex | |
227 | ) | |
228 | { | |
229 | unsigned char value = (0xFF); | |
230 | ||
231 | if (hwI2CWriteData(deviceAddress, 1, ®isterIndex) == 1) | |
232 | hwI2CReadData(deviceAddress, 1, &value); | |
233 | ||
234 | return value; | |
235 | } | |
236 | ||
237 | ||
238 | ||
239 | ||
240 | ||
241 | /* | |
242 | * This function writes a value to the slave device's register | |
243 | * | |
244 | * Parameters: | |
245 | * deviceAddress - i2c Slave device address which register | |
246 | * to be written | |
247 | * registerIndex - Slave device's register to be written | |
248 | * data - Data to be written to the register | |
249 | * | |
250 | * Result: | |
251 | * 0 - Success | |
252 | * -1 - Fail | |
253 | */ | |
254 | int hwI2CWriteReg( | |
255 | unsigned char deviceAddress, | |
256 | unsigned char registerIndex, | |
257 | unsigned char data | |
258 | ) | |
259 | { | |
260 | unsigned char value[2]; | |
261 | ||
262 | value[0] = registerIndex; | |
263 | value[1] = data; | |
264 | if (hwI2CWriteData(deviceAddress, 2, value) == 2) | |
265 | return 0; | |
266 | ||
267 | return (-1); | |
268 | } | |
269 | ||
270 | ||
271 | #endif |