projects / GitHub / mt8127 / android_kernel_alcatel_ttab.git / blame
| Commit | Line | Data |
|---|---|---|
| cecf61bd | 1 | /* rtc-sun4v.c: Hypervisor based RTC for SUN4V systems. |
| 7a138ede DM |
2 | * |
| 3 | * Copyright (C) 2008 David S. Miller <davem@davemloft.net> | |
| 4 | */ | |
| 5 | ||
| d959f731 JH |
6 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
| 7 | ||
| 7a138ede DM |
8 | #include <linux/kernel.h> |
| 9 | #include <linux/module.h> | |
| 10 | #include <linux/delay.h> | |
| 11 | #include <linux/init.h> | |
| 7a138ede DM |
12 | #include <linux/rtc.h> |
| 13 | #include <linux/platform_device.h> | |
| 14 | ||
| 15 | #include <asm/hypervisor.h> | |
| 16 | ||
| 7a138ede DM |
17 | static unsigned long hypervisor_get_time(void) |
| 18 | { | |
| 19 | unsigned long ret, time; | |
| 20 | int retries = 10000; | |
| 21 | ||
| 22 | retry: | |
| 23 | ret = sun4v_tod_get(&time); | |
| 24 | if (ret == HV_EOK) | |
| 25 | return time; | |
| 26 | if (ret == HV_EWOULDBLOCK) { | |
| 27 | if (--retries > 0) { | |
| 28 | udelay(100); | |
| 29 | goto retry; | |
| 30 | } | |
| d959f731 | 31 | pr_warn("tod_get() timed out.\n"); |
| 7a138ede DM |
32 | return 0; |
| 33 | } | |
| d959f731 | 34 | pr_warn("tod_get() not supported.\n"); |
| 7a138ede DM |
35 | return 0; |
| 36 | } | |
| 37 | ||
| 38 | static int sun4v_read_time(struct device *dev, struct rtc_time *tm) | |
| 39 | { | |
| cecf61bd | 40 | rtc_time_to_tm(hypervisor_get_time(), tm); |
| 7a138ede DM |
41 | return 0; |
| 42 | } | |
| 43 | ||
| 44 | static int hypervisor_set_time(unsigned long secs) | |
| 45 | { | |
| 46 | unsigned long ret; | |
| 47 | int retries = 10000; | |
| 48 | ||
| 49 | retry: | |
| 50 | ret = sun4v_tod_set(secs); | |
| 51 | if (ret == HV_EOK) | |
| 52 | return 0; | |
| 53 | if (ret == HV_EWOULDBLOCK) { | |
| 54 | if (--retries > 0) { | |
| 55 | udelay(100); | |
| 56 | goto retry; | |
| 57 | } | |
| d959f731 | 58 | pr_warn("tod_set() timed out.\n"); |
| 7a138ede DM |
59 | return -EAGAIN; |
| 60 | } | |
| d959f731 | 61 | pr_warn("tod_set() not supported.\n"); |
| 7a138ede DM |
62 | return -EOPNOTSUPP; |
| 63 | } | |
| 64 | ||
| 65 | static int sun4v_set_time(struct device *dev, struct rtc_time *tm) | |
| 66 | { | |
| cecf61bd | 67 | unsigned long secs; |
| 7a138ede DM |
68 | int err; |
| 69 | ||
| 70 | err = rtc_tm_to_time(tm, &secs); | |
| 71 | if (err) | |
| 72 | return err; | |
| 73 | ||
| cecf61bd | 74 | return hypervisor_set_time(secs); |
| 7a138ede DM |
75 | } |
| 76 | ||
| 77 | static const struct rtc_class_ops sun4v_rtc_ops = { | |
| 78 | .read_time = sun4v_read_time, | |
| 79 | .set_time = sun4v_set_time, | |
| 80 | }; | |
| 81 | ||
| cecf61bd | 82 | static int __init sun4v_rtc_probe(struct platform_device *pdev) |
| 7a138ede | 83 | { |
| cc40d642 JH |
84 | struct rtc_device *rtc; |
| 85 | ||
| 86 | rtc = devm_rtc_device_register(&pdev->dev, "sun4v", | |
| 87 | &sun4v_rtc_ops, THIS_MODULE); | |
| cecf61bd AZ |
88 | if (IS_ERR(rtc)) |
| 89 | return PTR_ERR(rtc); | |
| 90 | ||
| 91 | platform_set_drvdata(pdev, rtc); | |
| 7a138ede DM |
92 | return 0; |
| 93 | } | |
| 94 | ||
| cecf61bd | 95 | static int __exit sun4v_rtc_remove(struct platform_device *pdev) |
| 7a138ede | 96 | { |
| 7a138ede DM |
97 | return 0; |
| 98 | } | |
| 99 | ||
| 100 | static struct platform_driver sun4v_rtc_driver = { | |
| 101 | .driver = { | |
| 102 | .name = "rtc-sun4v", | |
| 103 | .owner = THIS_MODULE, | |
| 104 | }, | |
| cecf61bd | 105 | .remove = __exit_p(sun4v_rtc_remove), |
| 7a138ede DM |
106 | }; |
| 107 | ||
| 61ce8256 | 108 | module_platform_driver_probe(sun4v_rtc_driver, sun4v_rtc_probe); |
| cecf61bd AZ |
109 | |
| 110 | MODULE_AUTHOR("David S. Miller <davem@davemloft.net>"); | |
| 111 | MODULE_DESCRIPTION("SUN4V RTC driver"); | |
| 112 | MODULE_LICENSE("GPL"); |