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1// SPDX-License-Identifier: GPL-2.02/*3 * Linux driver for digital TV devices equipped with B2C2 FlexcopII(b)/III4 * flexcop-i2c.c - flexcop internal 2Wire bus (I2C) and dvb i2c initialization5 * see flexcop.c for copyright information6 */7#include "flexcop.h"8 9#define FC_MAX_I2C_RETRIES 10000010 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 work51 * correctly:52 *53 * the ITD1000 is behind an i2c-gate which closes automatically54 * after an i2c-transaction the STV0297 needs 2 consecutive reads55 * one with no_base_addr = 0 and one with 156 *57 * those two work-arounds are conflictin: we check for the card58 * 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 val0130 * 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 else147 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 this174 * driver doesn't support. These probes will always fail, so this175 * hack makes them always succeed. If one knew how, it would of176 * 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