Commit Graph

15 Commits

Author SHA1 Message Date
Andy Shevchenko
1481376072 rtc: mcp795: Switch to use %ptR
Use %ptR instead of open coded variant to print content of
struct rtc_time in human readable format.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
2018-12-10 22:39:52 +01:00
Gustavo A. R. Silva
fed9b18611 rtc: remove VLA usage
In preparation to enabling -Wvla, remove VLA and replace it
with a fixed-length array instead.

>From a security viewpoint, the use of Variable Length Arrays can be
a vector for stack overflow attacks. Also, in general, as the code
evolves it is easy to lose track of how big a VLA can get. Thus, we
can end up having segfaults that are hard to debug.

Also, fixed as part of the directive to remove all VLAs from
the kernel: https://lkml.org/lkml/2018/3/7/621

Signed-off-by: Gustavo A. R. Silva <garsilva@embeddedor.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
2018-03-17 14:20:56 +01:00
Alexandre Belloni
22652ba724 rtc: stop validating rtc_time in .read_time
The RTC core is always calling rtc_valid_tm after the read_time callback.
It is not necessary to call it just before returning from the callback.

Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
2018-03-02 10:09:58 +01:00
Emil Bartczak
644d4c366b rtc: mcp795: add alarm support.
This patch adds alarm support. This allows to configure the chip
to generate an interrupt when the alarm matches current time value.
Alarm can be programmed up to one year in the future
and is accurate to the second.

Signed-off-by: Emil Bartczak <emilbart@gmail.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2017-01-11 17:23:04 +01:00
Emil Bartczak
72877b51d0 rtc: mcp795: Add support for weekday.
This patch adds support for saving/loading weekday value from the chip.

Signed-off-by: Emil Bartczak <emilbart@gmail.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2017-01-11 17:23:04 +01:00
Emil Bartczak
d3e5925902 rtc: mcp795: Fix whitespace and indentation.
Fix whitespace and indentation errors and the following
checkpatch warnings:
- line 15: Block comments use a trailing */ on a separate line
- line 256: Line over 80 characters
No code change.

Signed-off-by: Emil Bartczak <emilbart@gmail.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2016-12-19 00:59:25 +01:00
Emil Bartczak
a2b4299751 rtc: mcp795: Prefer using the BIT() macro.
This patch doesn't change the code but replaces all bitmask values
with the BIT(x) macro.

Signed-off-by: Emil Bartczak <emilbart@gmail.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2016-12-19 00:59:24 +01:00
Emil Bartczak
43d0b10f60 rtc: mcp795: fix month write resetting date to 1.
According to Microchip errata some combinations of date and month
values may result in the date being reset to 1, even if the date
is also written with the month (for example 31-07 or 31-08).
As a workaround avoid writing date and month values within the same
Write command. Instead, terminate the Write command after loading
the date and begin a new command to write the month. In addition,
disable the oscillator before loading the new values. This is done
by ensuring both the ST and EXTOSC bits are cleared and waiting for
the OSCON bit to clear.

Signed-off-by: Emil Bartczak <emilbart@gmail.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2016-12-19 00:59:23 +01:00
Emil Bartczak
26eeefd595 rtc: mcp795: fix time range difference between linux and RTC chip.
In linux rtc_time struct, tm_mon range is 0~11, while in RTC HW REG,
month range is 1~12. This patch adjusts difference of them.

Signed-off-by: Emil Bartczak <emilbart@gmail.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2016-12-19 00:59:23 +01:00
Emil Bartczak
e72765c648 rtc: mcp795: fix bitmask value for leap year (LP).
According the datasheet the leap year is a fifth bit in month register.

Signed-off-by: Emil Bartczak <emilbart@gmail.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2016-12-19 00:59:22 +01:00
Emil Bartczak
bcf18d88ac rtc: mcp795: use bcd2bin/bin2bcd.
Change rtc-mcp795.c to use the bcd2bin/bin2bcd functions.
This change fixes the wrong conversion of month value
from binary to BCD (missing right shift operation for 10 month).

Signed-off-by: Emil Bartczak <emilbart@gmail.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2016-12-19 00:59:22 +01:00
Julia Lawall
34c7b3ac4c rtc: constify rtc_class_ops structures
Check for rtc_class_ops structures that are only passed to
devm_rtc_device_register, rtc_device_register,
platform_device_register_data, all of which declare the corresponding
parameter as const.  Declare rtc_class_ops structures that have these
properties as const.

The semantic patch that makes this change is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@r disable optional_qualifier@
identifier i;
position p;
@@
static struct rtc_class_ops i@p = { ... };

@ok@
identifier r.i;
expression e1,e2,e3,e4;
position p;
@@
(
devm_rtc_device_register(e1,e2,&i@p,e3)
|
rtc_device_register(e1,e2,&i@p,e3)
|
platform_device_register_data(e1,e2,e3,&i@p,e4)
)

@bad@
position p != {r.p,ok.p};
identifier r.i;
@@
i@p

@depends on !bad disable optional_qualifier@
identifier r.i;
@@
static
+const
 struct rtc_class_ops i = { ... };
// </smpl>

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Acked-by: Baruch Siach <baruch@tkos.co.il>
Acked-by: Hans Ulli Kroll <ulli.kroll@googlemail.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2016-09-02 01:24:06 +02:00
Emil Bartczak
7f8a58925b rtc: mcp795: add devicetree support
Add device tree support to the rtc-mcp795 driver.

Signed-off-by: Emil Bartczak <emilbart@gmail.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2016-03-21 22:55:29 +01:00
Andrew F. Davis
3821a065f5 spi: Drop owner assignment from spi_drivers
An spi_driver does not need to set an owner, it will be populated by the
driver core.

Signed-off-by: Andrew F. Davis <afd@ti.com>
Acked-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
2015-10-28 10:30:17 +09:00
Josef Gajdusek
1fcbe42c1b drivers/rtc: add support for Microchip MCP795
Add driver for SPI RTC Microchip MCP795.  Only supports saving/loading
time from the chip (i.  e.  no alarms/power events/ID).

Signed-off-by: Josef Gajdusek <atx@atx.name>
Cc: Jingoo Han <jg1.han@samsung.com>
Acked-by: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-06-06 16:08:08 -07:00