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(i2c->fc, &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(i2c->fc, &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); 105 } 106 107 int flexcop_i2c_request(struct flexcop_i2c_adapter *i2c, 108 flexcop_access_op_t op, u8 chipaddr, u8 addr, u8 *buf, u16 len) 109 { 110 int ret; 111 112 #ifdef DUMP_I2C_MESSAGES 113 int i; 114 #endif 115 116 u16 bytes_to_transfer; 117 flexcop_ibi_value r100; 118 119 deb_i2c("op = %d\n",op); 120 r100.raw = 0; 121 r100.tw_sm_c_100.chipaddr = chipaddr; 122 r100.tw_sm_c_100.twoWS_rw = op; 123 r100.tw_sm_c_100.twoWS_port_reg = i2c->port; 124 125 #ifdef DUMP_I2C_MESSAGES 126 printk(KERN_DEBUG "%d ", i2c->port); 127 if (op == FC_READ) 128 printk(KERN_CONT "rd("); 129 else 130 printk(KERN_CONT "wr("); 131 printk(KERN_CONT "%02x): %02x ", chipaddr, addr); 132 #endif 133 134 /* in that case addr is the only value -> 135 * we write it twice as baseaddr and val0 136 * BBTI is doing it like that for ISL6421 at least */ 137 if (i2c->no_base_addr && len == 0 && op == FC_WRITE) { 138 buf = &addr; 139 len = 1; 140 } 141 142 while (len != 0) { 143 bytes_to_transfer = len > 4 ? 4 : len; 144 145 r100.tw_sm_c_100.total_bytes = bytes_to_transfer - 1; 146 r100.tw_sm_c_100.baseaddr = addr; 147 148 if (op == FC_READ) 149 ret = flexcop_i2c_read4(i2c, r100, buf); 150 else 151 ret = flexcop_i2c_write4(i2c->fc, r100, buf); 152 153 #ifdef DUMP_I2C_MESSAGES 154 for (i = 0; i < bytes_to_transfer; i++) 155 printk(KERN_CONT "%02x ", buf[i]); 156 #endif 157 158 if (ret < 0) 159 return ret; 160 161 buf += bytes_to_transfer; 162 addr += bytes_to_transfer; 163 len -= bytes_to_transfer; 164 } 165 166 #ifdef DUMP_I2C_MESSAGES 167 printk(KERN_CONT "\n"); 168 #endif 169 170 return 0; 171 } 172 /* exported for PCI i2c */ 173 EXPORT_SYMBOL(flexcop_i2c_request); 174 175 /* master xfer callback for demodulator */ 176 static int flexcop_master_xfer(struct i2c_adapter *i2c_adap, 177 struct i2c_msg msgs[], int num) 178 { 179 struct flexcop_i2c_adapter *i2c = i2c_get_adapdata(i2c_adap); 180 int i, ret = 0; 181 182 /* Some drivers use 1 byte or 0 byte reads as probes, which this 183 * driver doesn't support. These probes will always fail, so this 184 * hack makes them always succeed. If one knew how, it would of 185 * course be better to actually do the read. */ 186 if (num == 1 && msgs[0].flags == I2C_M_RD && msgs[0].len <= 1) 187 return 1; 188 189 if (mutex_lock_interruptible(&i2c->fc->i2c_mutex)) 190 return -ERESTARTSYS; 191 192 for (i = 0; i < num; i++) { 193 /* reading */ 194 if (i+1 < num && (msgs[i+1].flags == I2C_M_RD)) { 195 ret = i2c->fc->i2c_request(i2c, FC_READ, msgs[i].addr, 196 msgs[i].buf[0], msgs[i+1].buf, 197 msgs[i+1].len); 198 i++; /* skip the following message */ 199 } else /* writing */ 200 ret = i2c->fc->i2c_request(i2c, FC_WRITE, msgs[i].addr, 201 msgs[i].buf[0], &msgs[i].buf[1], 202 msgs[i].len - 1); 203 if (ret < 0) { 204 deb_i2c("i2c master_xfer failed"); 205 break; 206 } 207 } 208 209 mutex_unlock(&i2c->fc->i2c_mutex); 210 211 if (ret == 0) 212 ret = num; 213 return ret; 214 } 215 216 static u32 flexcop_i2c_func(struct i2c_adapter *adapter) 217 { 218 return I2C_FUNC_I2C; 219 } 220 221 static struct i2c_algorithm flexcop_algo = { 222 .master_xfer = flexcop_master_xfer, 223 .functionality = flexcop_i2c_func, 224 }; 225 226 int flexcop_i2c_init(struct flexcop_device *fc) 227 { 228 int ret; 229 mutex_init(&fc->i2c_mutex); 230 231 fc->fc_i2c_adap[0].fc = fc; 232 fc->fc_i2c_adap[1].fc = fc; 233 fc->fc_i2c_adap[2].fc = fc; 234 fc->fc_i2c_adap[0].port = FC_I2C_PORT_DEMOD; 235 fc->fc_i2c_adap[1].port = FC_I2C_PORT_EEPROM; 236 fc->fc_i2c_adap[2].port = FC_I2C_PORT_TUNER; 237 238 strlcpy(fc->fc_i2c_adap[0].i2c_adap.name, "B2C2 FlexCop I2C to demod", 239 sizeof(fc->fc_i2c_adap[0].i2c_adap.name)); 240 strlcpy(fc->fc_i2c_adap[1].i2c_adap.name, "B2C2 FlexCop I2C to eeprom", 241 sizeof(fc->fc_i2c_adap[1].i2c_adap.name)); 242 strlcpy(fc->fc_i2c_adap[2].i2c_adap.name, "B2C2 FlexCop I2C to tuner", 243 sizeof(fc->fc_i2c_adap[2].i2c_adap.name)); 244 245 i2c_set_adapdata(&fc->fc_i2c_adap[0].i2c_adap, &fc->fc_i2c_adap[0]); 246 i2c_set_adapdata(&fc->fc_i2c_adap[1].i2c_adap, &fc->fc_i2c_adap[1]); 247 i2c_set_adapdata(&fc->fc_i2c_adap[2].i2c_adap, &fc->fc_i2c_adap[2]); 248 249 fc->fc_i2c_adap[0].i2c_adap.algo = 250 fc->fc_i2c_adap[1].i2c_adap.algo = 251 fc->fc_i2c_adap[2].i2c_adap.algo = &flexcop_algo; 252 fc->fc_i2c_adap[0].i2c_adap.algo_data = 253 fc->fc_i2c_adap[1].i2c_adap.algo_data = 254 fc->fc_i2c_adap[2].i2c_adap.algo_data = NULL; 255 fc->fc_i2c_adap[0].i2c_adap.dev.parent = 256 fc->fc_i2c_adap[1].i2c_adap.dev.parent = 257 fc->fc_i2c_adap[2].i2c_adap.dev.parent = fc->dev; 258 259 ret = i2c_add_adapter(&fc->fc_i2c_adap[0].i2c_adap); 260 if (ret < 0) 261 return ret; 262 263 ret = i2c_add_adapter(&fc->fc_i2c_adap[1].i2c_adap); 264 if (ret < 0) 265 goto adap_1_failed; 266 267 ret = i2c_add_adapter(&fc->fc_i2c_adap[2].i2c_adap); 268 if (ret < 0) 269 goto adap_2_failed; 270 271 fc->init_state |= FC_STATE_I2C_INIT; 272 return 0; 273 274 adap_2_failed: 275 i2c_del_adapter(&fc->fc_i2c_adap[1].i2c_adap); 276 adap_1_failed: 277 i2c_del_adapter(&fc->fc_i2c_adap[0].i2c_adap); 278 return ret; 279 } 280 281 void flexcop_i2c_exit(struct flexcop_device *fc) 282 { 283 if (fc->init_state & FC_STATE_I2C_INIT) { 284 i2c_del_adapter(&fc->fc_i2c_adap[2].i2c_adap); 285 i2c_del_adapter(&fc->fc_i2c_adap[1].i2c_adap); 286 i2c_del_adapter(&fc->fc_i2c_adap[0].i2c_adap); 287 } 288 fc->init_state &= ~FC_STATE_I2C_INIT; 289 } 290