Merge git://git.infradead.org/~dwmw2/dwmw2-2.6.27
[linux-2.6] / drivers / media / dvb / b2c2 / flexcop-i2c.c
1 /*
2  * This file is part of linux driver the digital TV devices equipped with B2C2 FlexcopII(b)/III
3  *
4  * flexcop-i2c.c - flexcop internal 2Wire bus (I2C) and dvb i2c initialization
5  *
6  * see flexcop.c for copyright information.
7  */
8 #include "flexcop.h"
9
10 #define FC_MAX_I2C_RETRIES 100000
11
12 /* #define DUMP_I2C_MESSAGES */
13
14 static int flexcop_i2c_operation(struct flexcop_device *fc, flexcop_ibi_value *r100)
15 {
16         int i;
17         flexcop_ibi_value r;
18
19         r100->tw_sm_c_100.working_start = 1;
20         deb_i2c("r100 before: %08x\n",r100->raw);
21
22         fc->write_ibi_reg(fc, tw_sm_c_100, ibi_zero);
23         fc->write_ibi_reg(fc, tw_sm_c_100, *r100); /* initiating i2c operation */
24
25         for (i = 0; i < FC_MAX_I2C_RETRIES; i++) {
26                 r = fc->read_ibi_reg(fc, tw_sm_c_100);
27
28                 if (!r.tw_sm_c_100.no_base_addr_ack_error) {
29                         if (r.tw_sm_c_100.st_done) {  /* && !r.tw_sm_c_100.working_start */
30                                 *r100 = r;
31                                 deb_i2c("i2c success\n");
32                                 return 0;
33                         }
34                 } else {
35                         deb_i2c("suffering from an i2c ack_error\n");
36                         return -EREMOTEIO;
37                 }
38         }
39         deb_i2c("tried %d times i2c operation, never finished or too many ack errors.\n",i);
40         return -EREMOTEIO;
41 }
42
43 static int flexcop_i2c_read4(struct flexcop_i2c_adapter *i2c,
44         flexcop_ibi_value r100, u8 *buf)
45 {
46         flexcop_ibi_value r104;
47         int len = r100.tw_sm_c_100.total_bytes, /* remember total_bytes is buflen-1 */
48                 ret;
49
50         r100.tw_sm_c_100.no_base_addr_ack_error = i2c->no_base_addr;
51         ret = flexcop_i2c_operation(i2c->fc, &r100);
52         if (ret != 0) {
53                 deb_i2c("read failed. %d\n", ret);
54                 return ret;
55         }
56
57         buf[0] = r100.tw_sm_c_100.data1_reg;
58
59         if (len > 0) {
60                 r104 = i2c->fc->read_ibi_reg(i2c->fc, tw_sm_c_104);
61                 deb_i2c("read: r100: %08x, r104: %08x\n", r100.raw, r104.raw);
62
63                 /* there is at least one more byte, otherwise we wouldn't be here */
64                 buf[1] = r104.tw_sm_c_104.data2_reg;
65                 if (len > 1) buf[2] = r104.tw_sm_c_104.data3_reg;
66                 if (len > 2) buf[3] = r104.tw_sm_c_104.data4_reg;
67         }
68
69         return 0;
70 }
71
72 static int flexcop_i2c_write4(struct flexcop_device *fc, flexcop_ibi_value r100, u8 *buf)
73 {
74         flexcop_ibi_value r104;
75         int len = r100.tw_sm_c_100.total_bytes; /* remember total_bytes is buflen-1 */
76         r104.raw = 0;
77
78         /* there is at least one byte, otherwise we wouldn't be here */
79         r100.tw_sm_c_100.data1_reg = buf[0];
80
81         r104.tw_sm_c_104.data2_reg = len > 0 ? buf[1] : 0;
82         r104.tw_sm_c_104.data3_reg = len > 1 ? buf[2] : 0;
83         r104.tw_sm_c_104.data4_reg = len > 2 ? buf[3] : 0;
84
85         deb_i2c("write: r100: %08x, r104: %08x\n", r100.raw, r104.raw);
86
87         /* write the additional i2c data before doing the actual i2c operation */
88         fc->write_ibi_reg(fc, tw_sm_c_104, r104);
89         return flexcop_i2c_operation(fc, &r100);
90 }
91
92 int flexcop_i2c_request(struct flexcop_i2c_adapter *i2c,
93         flexcop_access_op_t op, u8 chipaddr, u8 addr, u8 *buf, u16 len)
94 {
95         int ret;
96
97 #ifdef DUMP_I2C_MESSAGES
98         int i;
99 #endif
100
101         u16 bytes_to_transfer;
102         flexcop_ibi_value r100;
103
104         deb_i2c("op = %d\n",op);
105         r100.raw = 0;
106         r100.tw_sm_c_100.chipaddr = chipaddr;
107         r100.tw_sm_c_100.twoWS_rw = op;
108         r100.tw_sm_c_100.twoWS_port_reg = i2c->port;
109
110 #ifdef DUMP_I2C_MESSAGES
111         printk(KERN_DEBUG "%d ", i2c->port);
112         if (op == FC_READ)
113                 printk("rd(");
114         else
115                 printk("wr(");
116
117         printk("%02x): %02x ", chipaddr, addr);
118 #endif
119
120         /* in that case addr is the only value ->
121          * we write it twice as baseaddr and val0
122          * BBTI is doing it like that for ISL6421 at least */
123         if (i2c->no_base_addr && len == 0 && op == FC_WRITE) {
124                 buf = &addr;
125                 len = 1;
126         }
127
128         while (len != 0) {
129                 bytes_to_transfer = len > 4 ? 4 : len;
130
131                 r100.tw_sm_c_100.total_bytes = bytes_to_transfer - 1;
132                 r100.tw_sm_c_100.baseaddr = addr;
133
134                 if (op == FC_READ)
135                         ret = flexcop_i2c_read4(i2c, r100, buf);
136                 else
137                         ret = flexcop_i2c_write4(i2c->fc, r100, buf);
138
139 #ifdef DUMP_I2C_MESSAGES
140                 for (i = 0; i < bytes_to_transfer; i++)
141                         printk("%02x ", buf[i]);
142 #endif
143
144                 if (ret < 0)
145                         return ret;
146
147                 buf  += bytes_to_transfer;
148                 addr += bytes_to_transfer;
149                 len  -= bytes_to_transfer;
150         }
151
152 #ifdef DUMP_I2C_MESSAGES
153         printk("\n");
154 #endif
155
156         return 0;
157 }
158 /* exported for PCI i2c */
159 EXPORT_SYMBOL(flexcop_i2c_request);
160
161 /* master xfer callback for demodulator */
162 static int flexcop_master_xfer(struct i2c_adapter *i2c_adap, struct i2c_msg msgs[], int num)
163 {
164         struct flexcop_i2c_adapter *i2c = i2c_get_adapdata(i2c_adap);
165         int i, ret = 0;
166
167         /* Some drivers use 1 byte or 0 byte reads as probes, which this
168          * driver doesn't support.  These probes will always fail, so this
169          * hack makes them always succeed.  If one knew how, it would of
170          * course be better to actually do the read.  */
171         if (num == 1 && msgs[0].flags == I2C_M_RD && msgs[0].len <= 1)
172                 return 1;
173
174         if (mutex_lock_interruptible(&i2c->fc->i2c_mutex))
175                 return -ERESTARTSYS;
176
177         for (i = 0; i < num; i++) {
178                 /* reading */
179                 if (i+1 < num && (msgs[i+1].flags == I2C_M_RD)) {
180                         ret = i2c->fc->i2c_request(i2c, FC_READ, msgs[i].addr,
181                                 msgs[i].buf[0], msgs[i+1].buf, msgs[i+1].len);
182                         i++; /* skip the following message */
183                 } else /* writing */
184                         ret = i2c->fc->i2c_request(i2c, FC_WRITE, msgs[i].addr,
185                                 msgs[i].buf[0], &msgs[i].buf[1],
186                                 msgs[i].len - 1);
187                 if (ret < 0) {
188                         err("i2c master_xfer failed");
189                         break;
190                 }
191         }
192
193         mutex_unlock(&i2c->fc->i2c_mutex);
194
195         if (ret == 0)
196                 ret = num;
197         return ret;
198 }
199
200 static u32 flexcop_i2c_func(struct i2c_adapter *adapter)
201 {
202         return I2C_FUNC_I2C;
203 }
204
205 static struct i2c_algorithm flexcop_algo = {
206         .master_xfer    = flexcop_master_xfer,
207         .functionality  = flexcop_i2c_func,
208 };
209
210 int flexcop_i2c_init(struct flexcop_device *fc)
211 {
212         int ret;
213
214         mutex_init(&fc->i2c_mutex);
215
216         fc->fc_i2c_adap[0].fc = fc;
217         fc->fc_i2c_adap[1].fc = fc;
218         fc->fc_i2c_adap[2].fc = fc;
219
220         fc->fc_i2c_adap[0].port = FC_I2C_PORT_DEMOD;
221         fc->fc_i2c_adap[1].port = FC_I2C_PORT_EEPROM;
222         fc->fc_i2c_adap[2].port = FC_I2C_PORT_TUNER;
223
224         strlcpy(fc->fc_i2c_adap[0].i2c_adap.name, "B2C2 FlexCop I2C to demod",
225                 sizeof(fc->fc_i2c_adap[0].i2c_adap.name));
226         strlcpy(fc->fc_i2c_adap[1].i2c_adap.name, "B2C2 FlexCop I2C to eeprom",
227                 sizeof(fc->fc_i2c_adap[1].i2c_adap.name));
228         strlcpy(fc->fc_i2c_adap[2].i2c_adap.name, "B2C2 FlexCop I2C to tuner",
229                 sizeof(fc->fc_i2c_adap[2].i2c_adap.name));
230
231         i2c_set_adapdata(&fc->fc_i2c_adap[0].i2c_adap, &fc->fc_i2c_adap[0]);
232         i2c_set_adapdata(&fc->fc_i2c_adap[1].i2c_adap, &fc->fc_i2c_adap[1]);
233         i2c_set_adapdata(&fc->fc_i2c_adap[2].i2c_adap, &fc->fc_i2c_adap[2]);
234
235         fc->fc_i2c_adap[0].i2c_adap.class =
236                 fc->fc_i2c_adap[1].i2c_adap.class =
237                 fc->fc_i2c_adap[2].i2c_adap.class = I2C_CLASS_TV_DIGITAL;
238         fc->fc_i2c_adap[0].i2c_adap.algo =
239                 fc->fc_i2c_adap[1].i2c_adap.algo =
240                 fc->fc_i2c_adap[2].i2c_adap.algo = &flexcop_algo;
241         fc->fc_i2c_adap[0].i2c_adap.algo_data =
242                 fc->fc_i2c_adap[1].i2c_adap.algo_data =
243                 fc->fc_i2c_adap[2].i2c_adap.algo_data = NULL;
244         fc->fc_i2c_adap[0].i2c_adap.dev.parent =
245                 fc->fc_i2c_adap[1].i2c_adap.dev.parent =
246                 fc->fc_i2c_adap[2].i2c_adap.dev.parent = fc->dev;
247
248         ret = i2c_add_adapter(&fc->fc_i2c_adap[0].i2c_adap);
249         if (ret < 0)
250                 return ret;
251
252         ret = i2c_add_adapter(&fc->fc_i2c_adap[1].i2c_adap);
253         if (ret < 0)
254                 goto adap_1_failed;
255
256         ret = i2c_add_adapter(&fc->fc_i2c_adap[2].i2c_adap);
257         if (ret < 0)
258                 goto adap_2_failed;
259
260         fc->init_state |= FC_STATE_I2C_INIT;
261         return 0;
262
263 adap_2_failed:
264         i2c_del_adapter(&fc->fc_i2c_adap[1].i2c_adap);
265 adap_1_failed:
266         i2c_del_adapter(&fc->fc_i2c_adap[0].i2c_adap);
267
268         return ret;
269 }
270
271 void flexcop_i2c_exit(struct flexcop_device *fc)
272 {
273         if (fc->init_state & FC_STATE_I2C_INIT) {
274                 i2c_del_adapter(&fc->fc_i2c_adap[2].i2c_adap);
275                 i2c_del_adapter(&fc->fc_i2c_adap[1].i2c_adap);
276                 i2c_del_adapter(&fc->fc_i2c_adap[0].i2c_adap);
277         }
278
279         fc->init_state &= ~FC_STATE_I2C_INIT;
280 }