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20#include <linux/module.h>
21#include <linux/kernel.h>
22#include <linux/rtc.h>
23#include <linux/init.h>
24#include <linux/platform_device.h>
25#include <linux/io.h>
26#include <asm/mach-au1x00/au1000.h>
27
28
29#define CNTR_OK (SYS_CNTRL_E0 | SYS_CNTRL_32S)
30
31static int au1xtoy_rtc_read_time(struct device *dev, struct rtc_time *tm)
32{
33 unsigned long t;
34
35 t = alchemy_rdsys(AU1000_SYS_TOYREAD);
36
37 rtc_time64_to_tm(t, tm);
38
39 return 0;
40}
41
42static int au1xtoy_rtc_set_time(struct device *dev, struct rtc_time *tm)
43{
44 unsigned long t;
45
46 t = rtc_tm_to_time64(tm);
47
48 alchemy_wrsys(t, AU1000_SYS_TOYWRITE);
49
50
51
52
53 while (alchemy_rdsys(AU1000_SYS_CNTRCTRL) & SYS_CNTRL_C0S)
54 msleep(1);
55
56 return 0;
57}
58
59static const struct rtc_class_ops au1xtoy_rtc_ops = {
60 .read_time = au1xtoy_rtc_read_time,
61 .set_time = au1xtoy_rtc_set_time,
62};
63
64static int au1xtoy_rtc_probe(struct platform_device *pdev)
65{
66 struct rtc_device *rtcdev;
67 unsigned long t;
68
69 t = alchemy_rdsys(AU1000_SYS_CNTRCTRL);
70 if (!(t & CNTR_OK)) {
71 dev_err(&pdev->dev, "counters not working; aborting.\n");
72 return -ENODEV;
73 }
74
75
76 if (alchemy_rdsys(AU1000_SYS_TOYTRIM) != 32767) {
77
78 t = 0x00100000;
79 while ((alchemy_rdsys(AU1000_SYS_CNTRCTRL) & SYS_CNTRL_T0S) && --t)
80 msleep(1);
81
82 if (!t) {
83
84
85
86 dev_err(&pdev->dev, "timeout waiting for access\n");
87 return -ETIMEDOUT;
88 }
89
90
91 alchemy_wrsys(32767, AU1000_SYS_TOYTRIM);
92 }
93
94
95 while (alchemy_rdsys(AU1000_SYS_CNTRCTRL) & SYS_CNTRL_C0S)
96 msleep(1);
97
98 rtcdev = devm_rtc_allocate_device(&pdev->dev);
99 if (IS_ERR(rtcdev))
100 return PTR_ERR(rtcdev);
101
102 rtcdev->ops = &au1xtoy_rtc_ops;
103 rtcdev->range_max = U32_MAX;
104
105 platform_set_drvdata(pdev, rtcdev);
106
107 return devm_rtc_register_device(rtcdev);
108}
109
110static struct platform_driver au1xrtc_driver = {
111 .driver = {
112 .name = "rtc-au1xxx",
113 },
114};
115
116module_platform_driver_probe(au1xrtc_driver, au1xtoy_rtc_probe);
117
118MODULE_DESCRIPTION("Au1xxx TOY-counter-based RTC driver");
119MODULE_AUTHOR("Manuel Lauss <manuel.lauss@gmail.com>");
120MODULE_LICENSE("GPL");
121MODULE_ALIAS("platform:rtc-au1xxx");
122