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23#include <linux/module.h>
24#include <linux/usb.h>
25#include <linux/i2c.h>
26
27#include "stk1160.h"
28#include "stk1160-reg.h"
29
30static unsigned int i2c_debug;
31module_param(i2c_debug, int, 0644);
32MODULE_PARM_DESC(i2c_debug, "enable debug messages [i2c]");
33
34#define dprintk_i2c(fmt, args...) \
35do { \
36 if (i2c_debug) \
37 printk(KERN_DEBUG fmt, ##args); \
38} while (0)
39
40static int stk1160_i2c_busy_wait(struct stk1160 *dev, u8 wait_bit_mask)
41{
42 unsigned long end;
43 u8 flag;
44
45
46 end = jiffies + msecs_to_jiffies(STK1160_I2C_TIMEOUT);
47 while (time_is_after_jiffies(end)) {
48
49 stk1160_read_reg(dev, STK1160_SICTL+1, &flag);
50
51 if (flag & wait_bit_mask)
52 goto done;
53
54 usleep_range(10 * USEC_PER_MSEC, 20 * USEC_PER_MSEC);
55 }
56
57 return -ETIMEDOUT;
58
59done:
60 return 0;
61}
62
63static int stk1160_i2c_write_reg(struct stk1160 *dev, u8 addr,
64 u8 reg, u8 value)
65{
66 int rc;
67
68
69 rc = stk1160_write_reg(dev, STK1160_SICTL_SDA, addr);
70 if (rc < 0)
71 return rc;
72
73
74 rc = stk1160_write_reg(dev, STK1160_SBUSW_WA, reg);
75 if (rc < 0)
76 return rc;
77
78
79 rc = stk1160_write_reg(dev, STK1160_SBUSW_WD, value);
80 if (rc < 0)
81 return rc;
82
83
84 rc = stk1160_write_reg(dev, STK1160_SICTL, 0x01);
85 if (rc < 0)
86 return rc;
87
88 rc = stk1160_i2c_busy_wait(dev, 0x04);
89 if (rc < 0)
90 return rc;
91
92 return 0;
93}
94
95static int stk1160_i2c_read_reg(struct stk1160 *dev, u8 addr,
96 u8 reg, u8 *value)
97{
98 int rc;
99
100
101 rc = stk1160_write_reg(dev, STK1160_SICTL_SDA, addr);
102 if (rc < 0)
103 return rc;
104
105
106 rc = stk1160_write_reg(dev, STK1160_SBUSR_RA, reg);
107 if (rc < 0)
108 return rc;
109
110
111 rc = stk1160_write_reg(dev, STK1160_SICTL, 0x20);
112 if (rc < 0)
113 return rc;
114
115 rc = stk1160_i2c_busy_wait(dev, 0x01);
116 if (rc < 0)
117 return rc;
118
119 rc = stk1160_read_reg(dev, STK1160_SBUSR_RD, value);
120 if (rc < 0)
121 return rc;
122
123 return 0;
124}
125
126
127
128
129
130static int stk1160_i2c_check_for_device(struct stk1160 *dev,
131 unsigned char addr)
132{
133 int rc;
134
135
136 rc = stk1160_write_reg(dev, STK1160_SICTL_SDA, addr);
137 if (rc < 0)
138 return rc;
139
140
141 rc = stk1160_write_reg(dev, STK1160_SBUSR_RA, 0x00);
142 if (rc < 0)
143 return rc;
144
145
146 rc = stk1160_write_reg(dev, STK1160_SICTL, 0x20);
147 if (rc < 0)
148 return rc;
149
150 rc = stk1160_i2c_busy_wait(dev, 0x01);
151 if (rc < 0)
152 return -ENODEV;
153
154 return 0;
155}
156
157
158
159
160
161static int stk1160_i2c_xfer(struct i2c_adapter *i2c_adap,
162 struct i2c_msg msgs[], int num)
163{
164 struct stk1160 *dev = i2c_adap->algo_data;
165 int addr, rc, i;
166
167 for (i = 0; i < num; i++) {
168 addr = msgs[i].addr << 1;
169 dprintk_i2c("%s: addr=%x", __func__, addr);
170
171 if (!msgs[i].len) {
172
173 rc = stk1160_i2c_check_for_device(dev, addr);
174 if (rc < 0) {
175 dprintk_i2c(" no device\n");
176 return rc;
177 }
178
179 } else if (msgs[i].flags & I2C_M_RD) {
180
181 dprintk_i2c(" subaddr not selected");
182 rc = -EOPNOTSUPP;
183 goto err;
184
185 } else if (i + 1 < num && msgs[i].len <= 2 &&
186 (msgs[i + 1].flags & I2C_M_RD) &&
187 msgs[i].addr == msgs[i + 1].addr) {
188
189 if (msgs[i].len != 1 || msgs[i + 1].len != 1) {
190 dprintk_i2c(" len not supported");
191 rc = -EOPNOTSUPP;
192 goto err;
193 }
194
195 dprintk_i2c(" subaddr=%x", msgs[i].buf[0]);
196
197 rc = stk1160_i2c_read_reg(dev, addr, msgs[i].buf[0],
198 msgs[i + 1].buf);
199
200 dprintk_i2c(" read=%x", *msgs[i + 1].buf);
201
202
203 i++;
204
205 } else {
206 if (msgs[i].len != 2) {
207 dprintk_i2c(" len not supported");
208 rc = -EOPNOTSUPP;
209 goto err;
210 }
211
212 dprintk_i2c(" subaddr=%x write=%x",
213 msgs[i].buf[0], msgs[i].buf[1]);
214
215 rc = stk1160_i2c_write_reg(dev, addr, msgs[i].buf[0],
216 msgs[i].buf[1]);
217 }
218
219 if (rc < 0)
220 goto err;
221 dprintk_i2c(" OK\n");
222 }
223
224 return num;
225err:
226 dprintk_i2c(" ERROR: %d\n", rc);
227 return num;
228}
229
230
231
232
233static u32 functionality(struct i2c_adapter *adap)
234{
235 return I2C_FUNC_SMBUS_EMUL;
236}
237
238static struct i2c_algorithm algo = {
239 .master_xfer = stk1160_i2c_xfer,
240 .functionality = functionality,
241};
242
243static struct i2c_adapter adap_template = {
244 .owner = THIS_MODULE,
245 .name = "stk1160",
246 .algo = &algo,
247};
248
249static struct i2c_client client_template = {
250 .name = "stk1160 internal",
251};
252
253
254
255
256
257int stk1160_i2c_register(struct stk1160 *dev)
258{
259 int rc;
260
261 dev->i2c_adap = adap_template;
262 dev->i2c_adap.dev.parent = dev->dev;
263 strcpy(dev->i2c_adap.name, "stk1160");
264 dev->i2c_adap.algo_data = dev;
265
266 i2c_set_adapdata(&dev->i2c_adap, &dev->v4l2_dev);
267
268 rc = i2c_add_adapter(&dev->i2c_adap);
269 if (rc < 0) {
270 stk1160_err("cannot add i2c adapter (%d)\n", rc);
271 return rc;
272 }
273
274 dev->i2c_client = client_template;
275 dev->i2c_client.adapter = &dev->i2c_adap;
276
277
278 stk1160_write_reg(dev, STK1160_SICTL_CD, 0x0f);
279
280
281 stk1160_write_reg(dev, STK1160_ASIC + 3, 0x00);
282
283 return 0;
284}
285
286
287
288
289
290int stk1160_i2c_unregister(struct stk1160 *dev)
291{
292 i2c_del_adapter(&dev->i2c_adap);
293 return 0;
294}
295