This source file includes following definitions.
- rtc_reg_write
- rtc_reg_read
- rtc_datareg_read
- rtc_nrst_high
- rtc_nrst_low
- rtc_cycle_clock
- rtc_write_databit
- rtc_read_databit
- rtc_write_byte
- rtc_write_word
- rtc_read_word
- rtc_init_op
- rtc_end_op
- read_persistent_clock64
- update_persistent_clock64
- ds1603_set_trimmer
- ds1603_disable
- ds1603_enable
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8 #include <linux/kernel.h>
9 #include <asm/lasat/lasat.h>
10 #include <linux/delay.h>
11 #include <asm/lasat/ds1603.h>
12 #include <asm/time.h>
13
14 #include "ds1603.h"
15
16 #define READ_TIME_CMD 0x81
17 #define SET_TIME_CMD 0x80
18 #define TRIMMER_SET_CMD 0xC0
19 #define TRIMMER_VALUE_MASK 0x38
20 #define TRIMMER_SHIFT 3
21
22 struct ds_defs *ds1603;
23
24
25 static void rtc_reg_write(unsigned long val)
26 {
27 *ds1603->reg = val;
28 }
29
30 static unsigned long rtc_reg_read(void)
31 {
32 unsigned long tmp = *ds1603->reg;
33 return tmp;
34 }
35
36 static unsigned long rtc_datareg_read(void)
37 {
38 unsigned long tmp = *ds1603->data_reg;
39 return tmp;
40 }
41
42 static void rtc_nrst_high(void)
43 {
44 rtc_reg_write(rtc_reg_read() | ds1603->rst);
45 }
46
47 static void rtc_nrst_low(void)
48 {
49 rtc_reg_write(rtc_reg_read() & ~ds1603->rst);
50 }
51
52 static void rtc_cycle_clock(unsigned long data)
53 {
54 data |= ds1603->clk;
55 rtc_reg_write(data);
56 lasat_ndelay(250);
57 if (ds1603->data_reversed)
58 data &= ~ds1603->data;
59 else
60 data |= ds1603->data;
61 data &= ~ds1603->clk;
62 rtc_reg_write(data);
63 lasat_ndelay(250 + ds1603->huge_delay);
64 }
65
66 static void rtc_write_databit(unsigned int bit)
67 {
68 unsigned long data = rtc_reg_read();
69 if (ds1603->data_reversed)
70 bit = !bit;
71 if (bit)
72 data |= ds1603->data;
73 else
74 data &= ~ds1603->data;
75
76 rtc_reg_write(data);
77 lasat_ndelay(50 + ds1603->huge_delay);
78 rtc_cycle_clock(data);
79 }
80
81 static unsigned int rtc_read_databit(void)
82 {
83 unsigned int data;
84
85 data = (rtc_datareg_read() & (1 << ds1603->data_read_shift))
86 >> ds1603->data_read_shift;
87 rtc_cycle_clock(rtc_reg_read());
88 return data;
89 }
90
91 static void rtc_write_byte(unsigned int byte)
92 {
93 int i;
94
95 for (i = 0; i <= 7; i++) {
96 rtc_write_databit(byte & 1L);
97 byte >>= 1;
98 }
99 }
100
101 static void rtc_write_word(unsigned long word)
102 {
103 int i;
104
105 for (i = 0; i <= 31; i++) {
106 rtc_write_databit(word & 1L);
107 word >>= 1;
108 }
109 }
110
111 static unsigned long rtc_read_word(void)
112 {
113 int i;
114 unsigned long word = 0;
115 unsigned long shift = 0;
116
117 for (i = 0; i <= 31; i++) {
118 word |= rtc_read_databit() << shift;
119 shift++;
120 }
121 return word;
122 }
123
124 static void rtc_init_op(void)
125 {
126 rtc_nrst_high();
127
128 rtc_reg_write(rtc_reg_read() & ~ds1603->clk);
129
130 lasat_ndelay(50);
131 }
132
133 static void rtc_end_op(void)
134 {
135 rtc_nrst_low();
136 lasat_ndelay(1000);
137 }
138
139 void read_persistent_clock64(struct timespec64 *ts)
140 {
141 unsigned long word;
142 unsigned long flags;
143
144 spin_lock_irqsave(&rtc_lock, flags);
145 rtc_init_op();
146 rtc_write_byte(READ_TIME_CMD);
147 word = rtc_read_word();
148 rtc_end_op();
149 spin_unlock_irqrestore(&rtc_lock, flags);
150
151 ts->tv_sec = word;
152 ts->tv_nsec = 0;
153 }
154
155 int update_persistent_clock64(struct timespec64 now)
156 {
157 time64_t time = now.tv_sec;
158 unsigned long flags;
159
160 spin_lock_irqsave(&rtc_lock, flags);
161 rtc_init_op();
162 rtc_write_byte(SET_TIME_CMD);
163
164
165
166
167 rtc_write_word((unsigned long)time);
168 rtc_end_op();
169 spin_unlock_irqrestore(&rtc_lock, flags);
170
171 return 0;
172 }
173
174 void ds1603_set_trimmer(unsigned int trimval)
175 {
176 rtc_init_op();
177 rtc_write_byte(((trimval << TRIMMER_SHIFT) & TRIMMER_VALUE_MASK)
178 | (TRIMMER_SET_CMD));
179 rtc_end_op();
180 }
181
182 void ds1603_disable(void)
183 {
184 ds1603_set_trimmer(TRIMMER_DISABLE_RTC);
185 }
186
187 void ds1603_enable(void)
188 {
189 ds1603_set_trimmer(TRIMMER_DEFAULT);
190 }