231 lines · c
1// SPDX-License-Identifier: GPL-2.02/*3 * Earthsoft PT3 driver4 *5 * Copyright (C) 2014 Akihiro Tsukada <tskd08@gmail.com>6 */7#include <linux/delay.h>8#include <linux/device.h>9#include <linux/i2c.h>10#include <linux/io.h>11#include <linux/pci.h>12 13#include "pt3.h"14 15#define PT3_I2C_BASE 204816#define PT3_CMD_ADDR_NORMAL 017#define PT3_CMD_ADDR_INIT_DEMOD 409618#define PT3_CMD_ADDR_INIT_TUNER (4096 + 2042)19 20/* masks for I2C status register */21#define STAT_SEQ_RUNNING 0x122#define STAT_SEQ_ERROR 0x623#define STAT_NO_SEQ 0x824 25#define PT3_I2C_RUN (1 << 16)26#define PT3_I2C_RESET (1 << 17)27 28enum ctl_cmd {29 I_END,30 I_ADDRESS,31 I_CLOCK_L,32 I_CLOCK_H,33 I_DATA_L,34 I_DATA_H,35 I_RESET,36 I_SLEEP,37 I_DATA_L_NOP = 0x08,38 I_DATA_H_NOP = 0x0c,39 I_DATA_H_READ = 0x0d,40 I_DATA_H_ACK0 = 0x0e,41 I_DATA_H_ACK1 = 0x0f,42};43 44 45static void cmdbuf_add(struct pt3_i2cbuf *cbuf, enum ctl_cmd cmd)46{47 int buf_idx;48 49 if ((cbuf->num_cmds % 2) == 0)50 cbuf->tmp = cmd;51 else {52 cbuf->tmp |= cmd << 4;53 buf_idx = cbuf->num_cmds / 2;54 if (buf_idx < ARRAY_SIZE(cbuf->data))55 cbuf->data[buf_idx] = cbuf->tmp;56 }57 cbuf->num_cmds++;58}59 60static void put_end(struct pt3_i2cbuf *cbuf)61{62 cmdbuf_add(cbuf, I_END);63 if (cbuf->num_cmds % 2)64 cmdbuf_add(cbuf, I_END);65}66 67static void put_start(struct pt3_i2cbuf *cbuf)68{69 cmdbuf_add(cbuf, I_DATA_H);70 cmdbuf_add(cbuf, I_CLOCK_H);71 cmdbuf_add(cbuf, I_DATA_L);72 cmdbuf_add(cbuf, I_CLOCK_L);73}74 75static void put_byte_write(struct pt3_i2cbuf *cbuf, u8 val)76{77 u8 mask;78 79 for (mask = 0x80; mask > 0; mask >>= 1)80 cmdbuf_add(cbuf, (val & mask) ? I_DATA_H_NOP : I_DATA_L_NOP);81 cmdbuf_add(cbuf, I_DATA_H_ACK0);82}83 84static void put_byte_read(struct pt3_i2cbuf *cbuf, u32 size)85{86 int i, j;87 88 for (i = 0; i < size; i++) {89 for (j = 0; j < 8; j++)90 cmdbuf_add(cbuf, I_DATA_H_READ);91 cmdbuf_add(cbuf, (i == size - 1) ? I_DATA_H_NOP : I_DATA_L_NOP);92 }93}94 95static void put_stop(struct pt3_i2cbuf *cbuf)96{97 cmdbuf_add(cbuf, I_DATA_L);98 cmdbuf_add(cbuf, I_CLOCK_H);99 cmdbuf_add(cbuf, I_DATA_H);100}101 102 103/* translates msgs to internal commands for bit-banging */104static void translate(struct pt3_i2cbuf *cbuf, struct i2c_msg *msgs, int num)105{106 int i, j;107 bool rd;108 109 cbuf->num_cmds = 0;110 for (i = 0; i < num; i++) {111 rd = !!(msgs[i].flags & I2C_M_RD);112 put_start(cbuf);113 put_byte_write(cbuf, msgs[i].addr << 1 | rd);114 if (rd)115 put_byte_read(cbuf, msgs[i].len);116 else117 for (j = 0; j < msgs[i].len; j++)118 put_byte_write(cbuf, msgs[i].buf[j]);119 }120 if (num > 0) {121 put_stop(cbuf);122 put_end(cbuf);123 }124}125 126static int wait_i2c_result(struct pt3_board *pt3, u32 *result, int max_wait)127{128 int i;129 u32 v;130 131 for (i = 0; i < max_wait; i++) {132 v = ioread32(pt3->regs[0] + REG_I2C_R);133 if (!(v & STAT_SEQ_RUNNING))134 break;135 usleep_range(500, 750);136 }137 if (i >= max_wait)138 return -EIO;139 if (result)140 *result = v;141 return 0;142}143 144/* send [pre-]translated i2c msgs stored at addr */145static int send_i2c_cmd(struct pt3_board *pt3, u32 addr)146{147 u32 ret;148 149 /* make sure that previous transactions had finished */150 if (wait_i2c_result(pt3, NULL, 50)) {151 dev_warn(&pt3->pdev->dev, "(%s) prev. transaction stalled\n",152 __func__);153 return -EIO;154 }155 156 iowrite32(PT3_I2C_RUN | addr, pt3->regs[0] + REG_I2C_W);157 usleep_range(200, 300);158 /* wait for the current transaction to finish */159 if (wait_i2c_result(pt3, &ret, 500) || (ret & STAT_SEQ_ERROR)) {160 dev_warn(&pt3->pdev->dev, "(%s) failed.\n", __func__);161 return -EIO;162 }163 return 0;164}165 166 167/* init commands for each demod are combined into one transaction168 * and hidden in ROM with the address PT3_CMD_ADDR_INIT_DEMOD.169 */170int pt3_init_all_demods(struct pt3_board *pt3)171{172 ioread32(pt3->regs[0] + REG_I2C_R);173 return send_i2c_cmd(pt3, PT3_CMD_ADDR_INIT_DEMOD);174}175 176/* init commands for two ISDB-T tuners are hidden in ROM. */177int pt3_init_all_mxl301rf(struct pt3_board *pt3)178{179 usleep_range(1000, 2000);180 return send_i2c_cmd(pt3, PT3_CMD_ADDR_INIT_TUNER);181}182 183void pt3_i2c_reset(struct pt3_board *pt3)184{185 iowrite32(PT3_I2C_RESET, pt3->regs[0] + REG_I2C_W);186}187 188/*189 * I2C algorithm190 */191int192pt3_i2c_master_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num)193{194 struct pt3_board *pt3;195 struct pt3_i2cbuf *cbuf;196 int i;197 void __iomem *p;198 199 pt3 = i2c_get_adapdata(adap);200 cbuf = pt3->i2c_buf;201 202 for (i = 0; i < num; i++)203 if (msgs[i].flags & I2C_M_RECV_LEN) {204 dev_warn(&pt3->pdev->dev,205 "(%s) I2C_M_RECV_LEN not supported.\n",206 __func__);207 return -EINVAL;208 }209 210 translate(cbuf, msgs, num);211 memcpy_toio(pt3->regs[1] + PT3_I2C_BASE + PT3_CMD_ADDR_NORMAL / 2,212 cbuf->data, cbuf->num_cmds);213 214 if (send_i2c_cmd(pt3, PT3_CMD_ADDR_NORMAL) < 0)215 return -EIO;216 217 p = pt3->regs[1] + PT3_I2C_BASE;218 for (i = 0; i < num; i++)219 if ((msgs[i].flags & I2C_M_RD) && msgs[i].len > 0) {220 memcpy_fromio(msgs[i].buf, p, msgs[i].len);221 p += msgs[i].len;222 }223 224 return num;225}226 227u32 pt3_i2c_functionality(struct i2c_adapter *adap)228{229 return I2C_FUNC_I2C;230}231