1 | // SPDX-License-Identifier: GPL-2.0 |
2 | /* |
3 | * Linux driver for digital TV devices equipped with B2C2 FlexcopII(b)/III |
4 | * flexcop-i2c.c - flexcop internal 2Wire bus (I2C) and dvb i2c initialization |
5 | * see flexcop.c for copyright information |
6 | */ |
7 | #include "flexcop.h" |
8 | |
9 | #define FC_MAX_I2C_RETRIES 100000 |
10 | |
11 | static int flexcop_i2c_operation(struct flexcop_device *fc, |
12 | flexcop_ibi_value *r100) |
13 | { |
14 | int i; |
15 | flexcop_ibi_value r; |
16 | |
17 | r100->tw_sm_c_100.working_start = 1; |
18 | deb_i2c("r100 before: %08x\n" ,r100->raw); |
19 | |
20 | fc->write_ibi_reg(fc, tw_sm_c_100, ibi_zero); |
21 | fc->write_ibi_reg(fc, tw_sm_c_100, *r100); /* initiating i2c operation */ |
22 | |
23 | for (i = 0; i < FC_MAX_I2C_RETRIES; i++) { |
24 | r = fc->read_ibi_reg(fc, tw_sm_c_100); |
25 | |
26 | if (!r.tw_sm_c_100.no_base_addr_ack_error) { |
27 | if (r.tw_sm_c_100.st_done) { |
28 | *r100 = r; |
29 | deb_i2c("i2c success\n" ); |
30 | return 0; |
31 | } |
32 | } else { |
33 | deb_i2c("suffering from an i2c ack_error\n" ); |
34 | return -EREMOTEIO; |
35 | } |
36 | } |
37 | deb_i2c("tried %d times i2c operation, never finished or too many ack errors.\n" , |
38 | i); |
39 | return -EREMOTEIO; |
40 | } |
41 | |
42 | static int flexcop_i2c_read4(struct flexcop_i2c_adapter *i2c, |
43 | flexcop_ibi_value r100, u8 *buf) |
44 | { |
45 | flexcop_ibi_value r104; |
46 | int len = r100.tw_sm_c_100.total_bytes, |
47 | /* remember total_bytes is buflen-1 */ |
48 | ret; |
49 | |
50 | /* work-around to have CableStar2 and SkyStar2 rev 2.7 work |
51 | * correctly: |
52 | * |
53 | * the ITD1000 is behind an i2c-gate which closes automatically |
54 | * after an i2c-transaction the STV0297 needs 2 consecutive reads |
55 | * one with no_base_addr = 0 and one with 1 |
56 | * |
57 | * those two work-arounds are conflictin: we check for the card |
58 | * type, it is set when probing the ITD1000 */ |
59 | if (i2c->fc->dev_type == FC_SKY_REV27) |
60 | r100.tw_sm_c_100.no_base_addr_ack_error = i2c->no_base_addr; |
61 | |
62 | ret = flexcop_i2c_operation(fc: i2c->fc, r100: &r100); |
63 | if (ret != 0) { |
64 | deb_i2c("Retrying operation\n" ); |
65 | r100.tw_sm_c_100.no_base_addr_ack_error = i2c->no_base_addr; |
66 | ret = flexcop_i2c_operation(fc: i2c->fc, r100: &r100); |
67 | } |
68 | if (ret != 0) { |
69 | deb_i2c("read failed. %d\n" , ret); |
70 | return ret; |
71 | } |
72 | |
73 | buf[0] = r100.tw_sm_c_100.data1_reg; |
74 | |
75 | if (len > 0) { |
76 | r104 = i2c->fc->read_ibi_reg(i2c->fc, tw_sm_c_104); |
77 | deb_i2c("read: r100: %08x, r104: %08x\n" , r100.raw, r104.raw); |
78 | |
79 | /* there is at least one more byte, otherwise we wouldn't be here */ |
80 | buf[1] = r104.tw_sm_c_104.data2_reg; |
81 | if (len > 1) buf[2] = r104.tw_sm_c_104.data3_reg; |
82 | if (len > 2) buf[3] = r104.tw_sm_c_104.data4_reg; |
83 | } |
84 | return 0; |
85 | } |
86 | |
87 | static int flexcop_i2c_write4(struct flexcop_device *fc, |
88 | flexcop_ibi_value r100, u8 *buf) |
89 | { |
90 | flexcop_ibi_value r104; |
91 | int len = r100.tw_sm_c_100.total_bytes; /* remember total_bytes is buflen-1 */ |
92 | r104.raw = 0; |
93 | |
94 | /* there is at least one byte, otherwise we wouldn't be here */ |
95 | r100.tw_sm_c_100.data1_reg = buf[0]; |
96 | r104.tw_sm_c_104.data2_reg = len > 0 ? buf[1] : 0; |
97 | r104.tw_sm_c_104.data3_reg = len > 1 ? buf[2] : 0; |
98 | r104.tw_sm_c_104.data4_reg = len > 2 ? buf[3] : 0; |
99 | |
100 | deb_i2c("write: r100: %08x, r104: %08x\n" , r100.raw, r104.raw); |
101 | |
102 | /* write the additional i2c data before doing the actual i2c operation */ |
103 | fc->write_ibi_reg(fc, tw_sm_c_104, r104); |
104 | return flexcop_i2c_operation(fc, r100: &r100); |
105 | } |
106 | |
107 | int flexcop_i2c_request(struct flexcop_i2c_adapter *i2c, |
108 | flexcop_access_op_t op, u8 chipaddr, |
109 | u8 start_addr, u8 *buf, u16 size) |
110 | { |
111 | int ret; |
112 | int len = size; |
113 | u8 *p; |
114 | u8 addr = start_addr; |
115 | |
116 | u16 bytes_to_transfer; |
117 | flexcop_ibi_value r100; |
118 | |
119 | deb_i2c("port %d %s(%02x): register %02x, size: %d\n" , |
120 | i2c->port, |
121 | op == FC_READ ? "rd" : "wr" , |
122 | chipaddr, start_addr, size); |
123 | r100.raw = 0; |
124 | r100.tw_sm_c_100.chipaddr = chipaddr; |
125 | r100.tw_sm_c_100.twoWS_rw = op; |
126 | r100.tw_sm_c_100.twoWS_port_reg = i2c->port; |
127 | |
128 | /* in that case addr is the only value -> |
129 | * we write it twice as baseaddr and val0 |
130 | * BBTI is doing it like that for ISL6421 at least */ |
131 | if (i2c->no_base_addr && len == 0 && op == FC_WRITE) { |
132 | buf = &start_addr; |
133 | len = 1; |
134 | } |
135 | |
136 | p = buf; |
137 | |
138 | while (len != 0) { |
139 | bytes_to_transfer = len > 4 ? 4 : len; |
140 | |
141 | r100.tw_sm_c_100.total_bytes = bytes_to_transfer - 1; |
142 | r100.tw_sm_c_100.baseaddr = addr; |
143 | |
144 | if (op == FC_READ) |
145 | ret = flexcop_i2c_read4(i2c, r100, buf: p); |
146 | else |
147 | ret = flexcop_i2c_write4(fc: i2c->fc, r100, buf: p); |
148 | |
149 | if (ret < 0) |
150 | return ret; |
151 | |
152 | p += bytes_to_transfer; |
153 | addr += bytes_to_transfer; |
154 | len -= bytes_to_transfer; |
155 | } |
156 | deb_i2c_dump("port %d %s(%02x): register %02x: %*ph\n" , |
157 | i2c->port, |
158 | op == FC_READ ? "rd" : "wr" , |
159 | chipaddr, start_addr, size, buf); |
160 | |
161 | return 0; |
162 | } |
163 | /* exported for PCI i2c */ |
164 | EXPORT_SYMBOL(flexcop_i2c_request); |
165 | |
166 | /* master xfer callback for demodulator */ |
167 | static int flexcop_master_xfer(struct i2c_adapter *i2c_adap, |
168 | struct i2c_msg msgs[], int num) |
169 | { |
170 | struct flexcop_i2c_adapter *i2c = i2c_get_adapdata(adap: i2c_adap); |
171 | int i, ret = 0; |
172 | |
173 | /* Some drivers use 1 byte or 0 byte reads as probes, which this |
174 | * driver doesn't support. These probes will always fail, so this |
175 | * hack makes them always succeed. If one knew how, it would of |
176 | * course be better to actually do the read. */ |
177 | if (num == 1 && msgs[0].flags == I2C_M_RD && msgs[0].len <= 1) |
178 | return 1; |
179 | |
180 | if (mutex_lock_interruptible(&i2c->fc->i2c_mutex)) |
181 | return -ERESTARTSYS; |
182 | |
183 | for (i = 0; i < num; i++) { |
184 | /* reading */ |
185 | if (i+1 < num && (msgs[i+1].flags == I2C_M_RD)) { |
186 | ret = i2c->fc->i2c_request(i2c, FC_READ, msgs[i].addr, |
187 | msgs[i].buf[0], msgs[i+1].buf, |
188 | msgs[i+1].len); |
189 | i++; /* skip the following message */ |
190 | } else /* writing */ |
191 | ret = i2c->fc->i2c_request(i2c, FC_WRITE, msgs[i].addr, |
192 | msgs[i].buf[0], &msgs[i].buf[1], |
193 | msgs[i].len - 1); |
194 | if (ret < 0) { |
195 | deb_i2c("i2c master_xfer failed" ); |
196 | break; |
197 | } |
198 | } |
199 | |
200 | mutex_unlock(lock: &i2c->fc->i2c_mutex); |
201 | |
202 | if (ret == 0) |
203 | ret = num; |
204 | return ret; |
205 | } |
206 | |
207 | static u32 flexcop_i2c_func(struct i2c_adapter *adapter) |
208 | { |
209 | return I2C_FUNC_I2C; |
210 | } |
211 | |
212 | static struct i2c_algorithm flexcop_algo = { |
213 | .master_xfer = flexcop_master_xfer, |
214 | .functionality = flexcop_i2c_func, |
215 | }; |
216 | |
217 | int flexcop_i2c_init(struct flexcop_device *fc) |
218 | { |
219 | int ret; |
220 | mutex_init(&fc->i2c_mutex); |
221 | |
222 | fc->fc_i2c_adap[0].fc = fc; |
223 | fc->fc_i2c_adap[1].fc = fc; |
224 | fc->fc_i2c_adap[2].fc = fc; |
225 | fc->fc_i2c_adap[0].port = FC_I2C_PORT_DEMOD; |
226 | fc->fc_i2c_adap[1].port = FC_I2C_PORT_EEPROM; |
227 | fc->fc_i2c_adap[2].port = FC_I2C_PORT_TUNER; |
228 | |
229 | strscpy(fc->fc_i2c_adap[0].i2c_adap.name, "B2C2 FlexCop I2C to demod" , |
230 | sizeof(fc->fc_i2c_adap[0].i2c_adap.name)); |
231 | strscpy(fc->fc_i2c_adap[1].i2c_adap.name, "B2C2 FlexCop I2C to eeprom" , |
232 | sizeof(fc->fc_i2c_adap[1].i2c_adap.name)); |
233 | strscpy(fc->fc_i2c_adap[2].i2c_adap.name, "B2C2 FlexCop I2C to tuner" , |
234 | sizeof(fc->fc_i2c_adap[2].i2c_adap.name)); |
235 | |
236 | i2c_set_adapdata(adap: &fc->fc_i2c_adap[0].i2c_adap, data: &fc->fc_i2c_adap[0]); |
237 | i2c_set_adapdata(adap: &fc->fc_i2c_adap[1].i2c_adap, data: &fc->fc_i2c_adap[1]); |
238 | i2c_set_adapdata(adap: &fc->fc_i2c_adap[2].i2c_adap, data: &fc->fc_i2c_adap[2]); |
239 | |
240 | fc->fc_i2c_adap[0].i2c_adap.algo = |
241 | fc->fc_i2c_adap[1].i2c_adap.algo = |
242 | fc->fc_i2c_adap[2].i2c_adap.algo = &flexcop_algo; |
243 | fc->fc_i2c_adap[0].i2c_adap.algo_data = |
244 | fc->fc_i2c_adap[1].i2c_adap.algo_data = |
245 | fc->fc_i2c_adap[2].i2c_adap.algo_data = NULL; |
246 | fc->fc_i2c_adap[0].i2c_adap.dev.parent = |
247 | fc->fc_i2c_adap[1].i2c_adap.dev.parent = |
248 | fc->fc_i2c_adap[2].i2c_adap.dev.parent = fc->dev; |
249 | |
250 | ret = i2c_add_adapter(adap: &fc->fc_i2c_adap[0].i2c_adap); |
251 | if (ret < 0) |
252 | return ret; |
253 | |
254 | ret = i2c_add_adapter(adap: &fc->fc_i2c_adap[1].i2c_adap); |
255 | if (ret < 0) |
256 | goto adap_1_failed; |
257 | |
258 | ret = i2c_add_adapter(adap: &fc->fc_i2c_adap[2].i2c_adap); |
259 | if (ret < 0) |
260 | goto adap_2_failed; |
261 | |
262 | fc->init_state |= FC_STATE_I2C_INIT; |
263 | return 0; |
264 | |
265 | adap_2_failed: |
266 | i2c_del_adapter(adap: &fc->fc_i2c_adap[1].i2c_adap); |
267 | adap_1_failed: |
268 | i2c_del_adapter(adap: &fc->fc_i2c_adap[0].i2c_adap); |
269 | return ret; |
270 | } |
271 | |
272 | void flexcop_i2c_exit(struct flexcop_device *fc) |
273 | { |
274 | if (fc->init_state & FC_STATE_I2C_INIT) { |
275 | i2c_del_adapter(adap: &fc->fc_i2c_adap[2].i2c_adap); |
276 | i2c_del_adapter(adap: &fc->fc_i2c_adap[1].i2c_adap); |
277 | i2c_del_adapter(adap: &fc->fc_i2c_adap[0].i2c_adap); |
278 | } |
279 | fc->init_state &= ~FC_STATE_I2C_INIT; |
280 | } |
281 | |