starfive-tech/u-boot.git/drivers/rtc/ds1307.c, branch master

rtc: ds1307: Handle oscillator-stop bit correctly

2021-10-12T20:49:21+00:00

The DS1307 driver was originally based on the DS1337 driver. However, the functionality of the clock set/get functions has diverged. In the original DS1337 driver, the set/get functions did the following: 1) Setting the clock ensured the oscillator was enabled. 2) Getting the clock checked and reset the oscillator-stop flag. The DS1307 does not have an oscillator-stop flag, but the driver tried (incorrectly) to emulate this by ensuring the oscillator was running. It really makes no sense to start a stopped clock without setting it. This patch makes the DS1307 driver behave like the original DS1337 driver again. For the DS1307 itself, this is just a removal of code, since there is no oscillator-fail bit to check or reset, and the clock is started when it is set. Since the DS1307 driver can now also be used for the DS1337 and DS1340 which do have this bit, add code to handle the oscillator-stop bit in the same was the original DS1337 driver did -- i.e. report that the oscillator had stopped and clear the flag. This means that setting the date using the date command (which does both a get and a set) will now clear the oscillator-stop flag in addition to setting and starting the clock. The old-style (non-DM) code has not been updated and will be removed in a future patch. Note that this older code does not support the DS1337, as there is a separate driver for this. Also note that the original (DM) code used the wrong control-register address for the DS1337. Signed-off-by: Mark Tomlinson

rtc: ds1307: Fix incorrect clock reset for DS13xx

2021-09-01T23:25:37+00:00

The ds1307 driver also supports the DS1339 and DS1340. However, in ds1307_rtc_reset the register writes assume that the chip is a DS1307. This is evident in the writing of bits SQWE, RS1, RS0 to the control register. While this applies correctly to the DS1307, on a DS1340 the control register doesn't contain those bits (instead, the register is used for clock calibration). By writing these bits the clock calibration will be changed and the chip can become non-functional after a reset call. Signed-off-by: Callum Sinclair

rtc: ds1307: Add ds1339 compatible

2021-03-23T12:36:07+00:00

As far as u-boot is concerned the ds1339 is compatible with the other devices supported by the ds1307 driver. The Linux driver does expose some additional functionality but as far as u-boot is concerned just adding the compatible string is enough. Signed-off-by: Chris Packham Reviewed-by: Simon Glass Reviewed-by: Priyanka Jain

common: Drop log.h from common header

2020-05-19T01:19:18+00:00

Move this header out of the common header. Signed-off-by: Simon Glass

rtc: ds1307: add support for m41t11

2019-07-13T15:11:26+00:00

add m41t11 support in ds1307 driver. changes: - add compatible string for m41t11 - check if RTC clock is running, if not enable the clock Signed-off-by: Heiko Schocher

rtc: remove CONFIG_CMD_DATE dependency

2018-07-25T13:00:24+00:00

The EFI subsystem accesses the real time clock and is enabled by default. So we should drop any CONFIG_CMD_DATE dependency from the real time clock drivers. Signed-off-by: Heinrich Schuchardt Signed-off-by: Alexander Graf

SPDX: Convert all of our single license tags to Linux Kernel style

2018-05-07T13:34:12+00:00

When U-Boot started using SPDX tags we were among the early adopters and there weren't a lot of other examples to borrow from. So we picked the area of the file that usually had a full license text and replaced it with an appropriate SPDX-License-Identifier: entry. Since then, the Linux Kernel has adopted SPDX tags and they place it as the very first line in a file (except where shebangs are used, then it's second line) and with slightly different comment styles than us. In part due to community overlap, in part due to better tag visibility and in part for other minor reasons, switch over to that style. This commit changes all instances where we have a single declared license in the tag as both the before and after are identical in tag contents. There's also a few places where I found we did not have a tag and have introduced one. Signed-off-by: Tom Rini

rtc: ds1307: remove redundant code in rtc_reset

2018-04-07T00:45:44+00:00

As of commit 1a1fa2406689 ("rtc: Set valid date after reset") the command "date reset" will set the date/time to 2000-01-01 0:00:00 after calling rtc_reset(). This means that the ds1307 implementation of rtc_reset() doesn't need to call rtc_set(). Signed-off-by: Chris Packham Reviewed-by: Simon Glass

rtc: Add DM support to ds1307

2017-05-08T15:57:28+00:00

Add an implementation of the ds1307 driver that uses the driver model i2c APIs. Signed-off-by: Chris Packham Reviewed-by: Simon Glass

rtc: Add MCP79411 support to DS1307 rtc driver

2015-11-04T23:19:12+00:00

The code is from Adrian Cox, and is patterned after similar support in Linux (drivers/rtc/rtc-ds1307.c:1121-1135). This chip is used on the Cyrus board from Varisys. Signed-off-by: Andy Fleming Reviewed-by: York Sun