1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * Copyright (C) 2010-2013 Bluecherry, LLC <https://www.bluecherrydvr.com>
4 *
5 * Original author:
6 * Ben Collins <bcollins@ubuntu.com>
7 *
8 * Additional work by:
9 * John Brooks <john.brooks@bluecherry.net>
10 */
11
12 #include <linux/kernel.h>
13 #include <linux/delay.h>
14
15 #include "solo6x10.h"
16
17 /* Control */
18 #define EE_SHIFT_CLK 0x04
19 #define EE_CS 0x08
20 #define EE_DATA_WRITE 0x02
21 #define EE_DATA_READ 0x01
22 #define EE_ENB (0x80 | EE_CS)
23
24 #define eeprom_delay() udelay(100)
25 #if 0
26 #define eeprom_delay() solo_reg_read(solo_dev, SOLO_EEPROM_CTRL)
27 #define eeprom_delay() ({ \
28 int i, ret; \
29 udelay(100); \
30 for (i = ret = 0; i < 1000 && !ret; i++) \
31 ret = solo_eeprom_reg_read(solo_dev); \
32 })
33 #endif
34 #define ADDR_LEN 6
35
36 /* Commands */
37 #define EE_EWEN_CMD 4
38 #define EE_EWDS_CMD 4
39 #define EE_WRITE_CMD 5
40 #define EE_READ_CMD 6
41 #define EE_ERASE_CMD 7
42
solo_eeprom_reg_read(struct solo_dev * solo_dev)43 static unsigned int solo_eeprom_reg_read(struct solo_dev *solo_dev)
44 {
45 return solo_reg_read(solo_dev, SOLO_EEPROM_CTRL) & EE_DATA_READ;
46 }
47
solo_eeprom_reg_write(struct solo_dev * solo_dev,u32 data)48 static void solo_eeprom_reg_write(struct solo_dev *solo_dev, u32 data)
49 {
50 solo_reg_write(solo_dev, SOLO_EEPROM_CTRL, data);
51 eeprom_delay();
52 }
53
solo_eeprom_cmd(struct solo_dev * solo_dev,int cmd)54 static void solo_eeprom_cmd(struct solo_dev *solo_dev, int cmd)
55 {
56 int i;
57
58 solo_eeprom_reg_write(solo_dev, SOLO_EEPROM_ACCESS_EN);
59 solo_eeprom_reg_write(solo_dev, SOLO_EEPROM_ENABLE);
60
61 for (i = 4 + ADDR_LEN; i >= 0; i--) {
62 int dataval = (cmd & (1 << i)) ? EE_DATA_WRITE : 0;
63
64 solo_eeprom_reg_write(solo_dev, SOLO_EEPROM_ENABLE | dataval);
65 solo_eeprom_reg_write(solo_dev, SOLO_EEPROM_ENABLE |
66 EE_SHIFT_CLK | dataval);
67 }
68
69 solo_eeprom_reg_write(solo_dev, SOLO_EEPROM_ENABLE);
70 }
71
solo_eeprom_ewen(struct solo_dev * solo_dev,int w_en)72 unsigned int solo_eeprom_ewen(struct solo_dev *solo_dev, int w_en)
73 {
74 int ewen_cmd = (w_en ? 0x3f : 0) | (EE_EWEN_CMD << ADDR_LEN);
75 unsigned int retval = 0;
76 int i;
77
78 solo_eeprom_cmd(solo_dev, ewen_cmd);
79
80 for (i = 0; i < 16; i++) {
81 solo_eeprom_reg_write(solo_dev, SOLO_EEPROM_ENABLE |
82 EE_SHIFT_CLK);
83 retval = (retval << 1) | solo_eeprom_reg_read(solo_dev);
84 solo_eeprom_reg_write(solo_dev, SOLO_EEPROM_ENABLE);
85 retval = (retval << 1) | solo_eeprom_reg_read(solo_dev);
86 }
87
88 solo_eeprom_reg_write(solo_dev, ~EE_CS);
89 retval = (retval << 1) | solo_eeprom_reg_read(solo_dev);
90
91 return retval;
92 }
93
solo_eeprom_read(struct solo_dev * solo_dev,int loc)94 __be16 solo_eeprom_read(struct solo_dev *solo_dev, int loc)
95 {
96 int read_cmd = loc | (EE_READ_CMD << ADDR_LEN);
97 u16 retval = 0;
98 int i;
99
100 solo_eeprom_cmd(solo_dev, read_cmd);
101
102 for (i = 0; i < 16; i++) {
103 solo_eeprom_reg_write(solo_dev, SOLO_EEPROM_ENABLE |
104 EE_SHIFT_CLK);
105 retval = (retval << 1) | solo_eeprom_reg_read(solo_dev);
106 solo_eeprom_reg_write(solo_dev, SOLO_EEPROM_ENABLE);
107 }
108
109 solo_eeprom_reg_write(solo_dev, ~EE_CS);
110
111 return (__force __be16)retval;
112 }
113
solo_eeprom_write(struct solo_dev * solo_dev,int loc,__be16 data)114 int solo_eeprom_write(struct solo_dev *solo_dev, int loc,
115 __be16 data)
116 {
117 int write_cmd = loc | (EE_WRITE_CMD << ADDR_LEN);
118 unsigned int retval;
119 int i;
120
121 solo_eeprom_cmd(solo_dev, write_cmd);
122
123 for (i = 15; i >= 0; i--) {
124 unsigned int dataval = ((__force unsigned)data >> i) & 1;
125
126 solo_eeprom_reg_write(solo_dev, EE_ENB);
127 solo_eeprom_reg_write(solo_dev,
128 EE_ENB | (dataval << 1) | EE_SHIFT_CLK);
129 }
130
131 solo_eeprom_reg_write(solo_dev, EE_ENB);
132 solo_eeprom_reg_write(solo_dev, ~EE_CS);
133 solo_eeprom_reg_write(solo_dev, EE_ENB);
134
135 for (i = retval = 0; i < 10000 && !retval; i++)
136 retval = solo_eeprom_reg_read(solo_dev);
137
138 solo_eeprom_reg_write(solo_dev, ~EE_CS);
139
140 return !retval;
141 }
142