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 11static 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 42static 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 87static 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 107int 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, p); 146 else 147 ret = flexcop_i2c_write4(i2c->fc, r100, 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 */ 164EXPORT_SYMBOL(flexcop_i2c_request); 165 166/* master xfer callback for demodulator */ 167static 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(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(&i2c->fc->i2c_mutex); 201 202 if (ret == 0) 203 ret = num; 204 return ret; 205} 206 207static u32 flexcop_i2c_func(struct i2c_adapter *adapter) 208{ 209 return I2C_FUNC_I2C; 210} 211 212static struct i2c_algorithm flexcop_algo = { 213 .master_xfer = flexcop_master_xfer, 214 .functionality = flexcop_i2c_func, 215}; 216 217int 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(&fc->fc_i2c_adap[0].i2c_adap, &fc->fc_i2c_adap[0]); 237 i2c_set_adapdata(&fc->fc_i2c_adap[1].i2c_adap, &fc->fc_i2c_adap[1]); 238 i2c_set_adapdata(&fc->fc_i2c_adap[2].i2c_adap, &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(&fc->fc_i2c_adap[0].i2c_adap); 251 if (ret < 0) 252 return ret; 253 254 ret = i2c_add_adapter(&fc->fc_i2c_adap[1].i2c_adap); 255 if (ret < 0) 256 goto adap_1_failed; 257 258 ret = i2c_add_adapter(&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 265adap_2_failed: 266 i2c_del_adapter(&fc->fc_i2c_adap[1].i2c_adap); 267adap_1_failed: 268 i2c_del_adapter(&fc->fc_i2c_adap[0].i2c_adap); 269 return ret; 270} 271 272void flexcop_i2c_exit(struct flexcop_device *fc) 273{ 274 if (fc->init_state & FC_STATE_I2C_INIT) { 275 i2c_del_adapter(&fc->fc_i2c_adap[2].i2c_adap); 276 i2c_del_adapter(&fc->fc_i2c_adap[1].i2c_adap); 277 i2c_del_adapter(&fc->fc_i2c_adap[0].i2c_adap); 278 } 279 fc->init_state &= ~FC_STATE_I2C_INIT; 280} 281