1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Earthsoft PT3 driver
4 *
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 2048
16 #define PT3_CMD_ADDR_NORMAL 0
17 #define PT3_CMD_ADDR_INIT_DEMOD 4096
18 #define PT3_CMD_ADDR_INIT_TUNER (4096 + 2042)
19
20 /* masks for I2C status register */
21 #define STAT_SEQ_RUNNING 0x1
22 #define STAT_SEQ_ERROR 0x6
23 #define STAT_NO_SEQ 0x8
24
25 #define PT3_I2C_RUN (1 << 16)
26 #define PT3_I2C_RESET (1 << 17)
27
28 enum 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
cmdbuf_add(struct pt3_i2cbuf * cbuf,enum ctl_cmd cmd)45 static 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
put_end(struct pt3_i2cbuf * cbuf)60 static 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
put_start(struct pt3_i2cbuf * cbuf)67 static 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
put_byte_write(struct pt3_i2cbuf * cbuf,u8 val)75 static 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
put_byte_read(struct pt3_i2cbuf * cbuf,u32 size)84 static 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
put_stop(struct pt3_i2cbuf * cbuf)95 static 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 */
translate(struct pt3_i2cbuf * cbuf,struct i2c_msg * msgs,int num)104 static 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 else
117 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
wait_i2c_result(struct pt3_board * pt3,u32 * result,int max_wait)126 static 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 */
send_i2c_cmd(struct pt3_board * pt3,u32 addr)145 static 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 transaction
168 * and hidden in ROM with the address PT3_CMD_ADDR_INIT_DEMOD.
169 */
pt3_init_all_demods(struct pt3_board * pt3)170 int 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. */
pt3_init_all_mxl301rf(struct pt3_board * pt3)177 int 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
pt3_i2c_reset(struct pt3_board * pt3)183 void pt3_i2c_reset(struct pt3_board *pt3)
184 {
185 iowrite32(PT3_I2C_RESET, pt3->regs[0] + REG_I2C_W);
186 }
187
188 /*
189 * I2C algorithm
190 */
191 int
pt3_i2c_master_xfer(struct i2c_adapter * adap,struct i2c_msg * msgs,int num)192 pt3_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
pt3_i2c_functionality(struct i2c_adapter * adap)227 u32 pt3_i2c_functionality(struct i2c_adapter *adap)
228 {
229 return I2C_FUNC_I2C;
230 }
231