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authorLinus Torvalds <torvalds@linux-foundation.org>2019-03-12 12:46:32 -0400
committerLinus Torvalds <torvalds@linux-foundation.org>2019-03-12 12:46:32 -0400
commitf47d633134f7033e3d0c667419d9f8afd69e308d (patch)
treea5242d86288599fda63ed79b2d131f5a298bb66f /drivers/rtc
parent004cc08675b761fd82288bab1b5ba5e1ca746eca (diff)
parent2794449576a6024e203eca5cc2c1a3ae33102b8e (diff)
Merge tag 'tag-chrome-platform-for-v5.1' of git://git.kernel.org/pub/scm/linux/kernel/git/chrome-platform/linux
Pull chrome platform updates from Benson Leung: - SPDX identifier cleanup for platform/chrome - Cleanup series between mfd and chrome/platform, moving cros-ec attributes from mfd/cros_ec_dev to sub-drivers in platform/chrome - Wilco EC driver - Maintainership change to new group repository * tag 'tag-chrome-platform-for-v5.1' of git://git.kernel.org/pub/scm/linux/kernel/git/chrome-platform/linux: platform/chrome: fix wilco-ec dependencies platform/chrome: wilco_ec: Add RTC driver platform/chrome: wilco_ec: Add support for raw commands in debugfs platform/chrome: Add new driver for Wilco EC platform/chrome: cros_ec: Remove cros_ec dependency in lpc_mec MAINTAINERS: chrome-platform: change the git tree to a chrome-platform group git tree platform/chrome: cros_ec_sysfs: remove pr_fmt() define platform/chrome: cros_ec_lightbar: remove pr_fmt() define platform/chrome: cros_kbd_led_backlight: switch to SPDX identifier platform/chrome: cros_ec_spi: switch to SPDX identifier platform/chrome: cros_ec_proto: switch to SPDX identifier platform/chrome: cros_ec_lpc: switch to SPDX identifier platform/chrome: cros_ec_i2c: switch to SPDX identifier platform/chrome: cros_ec_vbc: switch to SPDX identifier platform/chrome: cros_ec_sysfs: switch to SPDX identifier platform/chrome: cros_ec_lightbar: switch to SPDX identifier platform/chrome: cros_ec_debugfs: switch to SPDX identifier platform/chrome: cromeos_pstore: switch to SPDX identifier
Diffstat (limited to 'drivers/rtc')
-rw-r--r--drivers/rtc/Kconfig11
-rw-r--r--drivers/rtc/Makefile1
-rw-r--r--drivers/rtc/rtc-wilco-ec.c177
3 files changed, 189 insertions, 0 deletions
diff --git a/drivers/rtc/Kconfig b/drivers/rtc/Kconfig
index e1a1f2b1cbba..a71734c41693 100644
--- a/drivers/rtc/Kconfig
+++ b/drivers/rtc/Kconfig
@@ -1864,4 +1864,15 @@ config RTC_DRV_GOLDFISH
1864 Goldfish is a code name for the virtual platform developed by Google 1864 Goldfish is a code name for the virtual platform developed by Google
1865 for Android emulation. 1865 for Android emulation.
1866 1866
1867config RTC_DRV_WILCO_EC
1868 tristate "Wilco EC RTC"
1869 depends on WILCO_EC
1870 default m
1871 help
1872 If you say yes here, you get read/write support for the Real Time
1873 Clock on the Wilco Embedded Controller (Wilco is a kind of Chromebook)
1874
1875 This can also be built as a module. If so, the module will
1876 be named "rtc_wilco_ec".
1877
1867endif # RTC_CLASS 1878endif # RTC_CLASS
diff --git a/drivers/rtc/Makefile b/drivers/rtc/Makefile
index 1bf9f75a7865..fe3962496685 100644
--- a/drivers/rtc/Makefile
+++ b/drivers/rtc/Makefile
@@ -177,6 +177,7 @@ obj-$(CONFIG_RTC_DRV_V3020) += rtc-v3020.o
177obj-$(CONFIG_RTC_DRV_VR41XX) += rtc-vr41xx.o 177obj-$(CONFIG_RTC_DRV_VR41XX) += rtc-vr41xx.o
178obj-$(CONFIG_RTC_DRV_VRTC) += rtc-mrst.o 178obj-$(CONFIG_RTC_DRV_VRTC) += rtc-mrst.o
179obj-$(CONFIG_RTC_DRV_VT8500) += rtc-vt8500.o 179obj-$(CONFIG_RTC_DRV_VT8500) += rtc-vt8500.o
180obj-$(CONFIG_RTC_DRV_WILCO_EC) += rtc-wilco-ec.o
180obj-$(CONFIG_RTC_DRV_WM831X) += rtc-wm831x.o 181obj-$(CONFIG_RTC_DRV_WM831X) += rtc-wm831x.o
181obj-$(CONFIG_RTC_DRV_WM8350) += rtc-wm8350.o 182obj-$(CONFIG_RTC_DRV_WM8350) += rtc-wm8350.o
182obj-$(CONFIG_RTC_DRV_X1205) += rtc-x1205.o 183obj-$(CONFIG_RTC_DRV_X1205) += rtc-x1205.o
diff --git a/drivers/rtc/rtc-wilco-ec.c b/drivers/rtc/rtc-wilco-ec.c
new file mode 100644
index 000000000000..e62bda0cb53e
--- /dev/null
+++ b/drivers/rtc/rtc-wilco-ec.c
@@ -0,0 +1,177 @@
1// SPDX-License-Identifier: GPL-2.0
2/*
3 * RTC interface for Wilco Embedded Controller with R/W abilities
4 *
5 * Copyright 2018 Google LLC
6 *
7 * The corresponding platform device is typically registered in
8 * drivers/platform/chrome/wilco_ec/core.c
9 */
10
11#include <linux/bcd.h>
12#include <linux/err.h>
13#include <linux/kernel.h>
14#include <linux/module.h>
15#include <linux/platform_device.h>
16#include <linux/platform_data/wilco-ec.h>
17#include <linux/rtc.h>
18#include <linux/timekeeping.h>
19
20#define EC_COMMAND_CMOS 0x7c
21#define EC_CMOS_TOD_WRITE 0x02
22#define EC_CMOS_TOD_READ 0x08
23
24/**
25 * struct ec_rtc_read - Format of RTC returned by EC.
26 * @second: Second value (0..59)
27 * @minute: Minute value (0..59)
28 * @hour: Hour value (0..23)
29 * @day: Day value (1..31)
30 * @month: Month value (1..12)
31 * @year: Year value (full year % 100)
32 * @century: Century value (full year / 100)
33 *
34 * All values are presented in binary (not BCD).
35 */
36struct ec_rtc_read {
37 u8 second;
38 u8 minute;
39 u8 hour;
40 u8 day;
41 u8 month;
42 u8 year;
43 u8 century;
44} __packed;
45
46/**
47 * struct ec_rtc_write - Format of RTC sent to the EC.
48 * @param: EC_CMOS_TOD_WRITE
49 * @century: Century value (full year / 100)
50 * @year: Year value (full year % 100)
51 * @month: Month value (1..12)
52 * @day: Day value (1..31)
53 * @hour: Hour value (0..23)
54 * @minute: Minute value (0..59)
55 * @second: Second value (0..59)
56 * @weekday: Day of the week (0=Saturday)
57 *
58 * All values are presented in BCD.
59 */
60struct ec_rtc_write {
61 u8 param;
62 u8 century;
63 u8 year;
64 u8 month;
65 u8 day;
66 u8 hour;
67 u8 minute;
68 u8 second;
69 u8 weekday;
70} __packed;
71
72static int wilco_ec_rtc_read(struct device *dev, struct rtc_time *tm)
73{
74 struct wilco_ec_device *ec = dev_get_drvdata(dev->parent);
75 u8 param = EC_CMOS_TOD_READ;
76 struct ec_rtc_read rtc;
77 struct wilco_ec_message msg = {
78 .type = WILCO_EC_MSG_LEGACY,
79 .flags = WILCO_EC_FLAG_RAW_RESPONSE,
80 .command = EC_COMMAND_CMOS,
81 .request_data = &param,
82 .request_size = sizeof(param),
83 .response_data = &rtc,
84 .response_size = sizeof(rtc),
85 };
86 int ret;
87
88 ret = wilco_ec_mailbox(ec, &msg);
89 if (ret < 0)
90 return ret;
91
92 tm->tm_sec = rtc.second;
93 tm->tm_min = rtc.minute;
94 tm->tm_hour = rtc.hour;
95 tm->tm_mday = rtc.day;
96 tm->tm_mon = rtc.month - 1;
97 tm->tm_year = rtc.year + (rtc.century * 100) - 1900;
98 tm->tm_yday = rtc_year_days(tm->tm_mday, tm->tm_mon, tm->tm_year);
99
100 /* Don't compute day of week, we don't need it. */
101 tm->tm_wday = -1;
102
103 return 0;
104}
105
106static int wilco_ec_rtc_write(struct device *dev, struct rtc_time *tm)
107{
108 struct wilco_ec_device *ec = dev_get_drvdata(dev->parent);
109 struct ec_rtc_write rtc;
110 struct wilco_ec_message msg = {
111 .type = WILCO_EC_MSG_LEGACY,
112 .flags = WILCO_EC_FLAG_RAW_RESPONSE,
113 .command = EC_COMMAND_CMOS,
114 .request_data = &rtc,
115 .request_size = sizeof(rtc),
116 };
117 int year = tm->tm_year + 1900;
118 /*
119 * Convert from 0=Sunday to 0=Saturday for the EC
120 * We DO need to set weekday because the EC controls battery charging
121 * schedules that depend on the day of the week.
122 */
123 int wday = tm->tm_wday == 6 ? 0 : tm->tm_wday + 1;
124 int ret;
125
126 rtc.param = EC_CMOS_TOD_WRITE;
127 rtc.century = bin2bcd(year / 100);
128 rtc.year = bin2bcd(year % 100);
129 rtc.month = bin2bcd(tm->tm_mon + 1);
130 rtc.day = bin2bcd(tm->tm_mday);
131 rtc.hour = bin2bcd(tm->tm_hour);
132 rtc.minute = bin2bcd(tm->tm_min);
133 rtc.second = bin2bcd(tm->tm_sec);
134 rtc.weekday = bin2bcd(wday);
135
136 ret = wilco_ec_mailbox(ec, &msg);
137 if (ret < 0)
138 return ret;
139
140 return 0;
141}
142
143static const struct rtc_class_ops wilco_ec_rtc_ops = {
144 .read_time = wilco_ec_rtc_read,
145 .set_time = wilco_ec_rtc_write,
146};
147
148static int wilco_ec_rtc_probe(struct platform_device *pdev)
149{
150 struct rtc_device *rtc;
151
152 rtc = devm_rtc_allocate_device(&pdev->dev);
153 if (IS_ERR(rtc))
154 return PTR_ERR(rtc);
155
156 rtc->ops = &wilco_ec_rtc_ops;
157 /* EC only supports this century */
158 rtc->range_min = RTC_TIMESTAMP_BEGIN_2000;
159 rtc->range_max = RTC_TIMESTAMP_END_2099;
160 rtc->owner = THIS_MODULE;
161
162 return rtc_register_device(rtc);
163}
164
165static struct platform_driver wilco_ec_rtc_driver = {
166 .driver = {
167 .name = "rtc-wilco-ec",
168 },
169 .probe = wilco_ec_rtc_probe,
170};
171
172module_platform_driver(wilco_ec_rtc_driver);
173
174MODULE_ALIAS("platform:rtc-wilco-ec");
175MODULE_AUTHOR("Nick Crews <ncrews@chromium.org>");
176MODULE_LICENSE("GPL v2");
177MODULE_DESCRIPTION("Wilco EC RTC driver");