Commit Graph

12 Commits

Author SHA1 Message Date
Alexandre Belloni 606cc43c72 rtc: core: correct trivial checkpatch warnings
Correct trivial checkpatch warnings, mostly whitespace issues and
unbalanced braces.

Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
2019-04-04 10:07:08 +02:00
Alexandre Belloni cdf7545aef rtc: convert core to SPDX identifier
Use SPDX-License-Identifier instead of a verbose license text. Also fix the
block comment alignment.

Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
2019-03-18 03:36:01 +01:00
Alexandre Belloni bba3d2daa8 rtc: nvmem: fix possible use after free
In cas of probe failure, devres may free the memory allocated for
rtc->nvram before devm_rtc_release_device() is called. This leads to
rtc_nvram_unregister using it after being freed which may lead to a crash.

This has been shown to happen after commit 461e557b97 ("rtc: nvmem: use
devm_nvmem_register()")

Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
2018-12-31 00:49:36 +01:00
Alexandre Belloni 41c9e132c5 rtc: nvmem: remove nvmem from struct rtc_device
Using devm_nvmem_register allows to avoid tracking the nvmem pointer in the
rtc_device structure.
This ultimately allows to register multiple nvmem devices from an RTC
driver.

Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
2018-11-22 18:10:07 +01:00
Alexandre Belloni 461e557b97 rtc: nvmem: use devm_nvmem_register()
Use the resource managed variant of nvmem_register().

Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
2018-11-22 18:10:04 +01:00
Uwe Kleine-König 046dbb2420 rtc: nvmem: don't use IS_ERR_OR_NULL
nvmem_register() never returns NULL, so IS_ERR is good enough here.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
2018-05-21 22:34:38 +02:00
Alexandre Belloni fd5cd21d99 rtc: export rtc_nvmem_register() to drivers
Export rtc_nvmem_register() so it can be called from drivers instead of
only the core.

Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
2018-03-01 10:49:15 +01:00
Alexandre Belloni ac75779b72 rtc: nvmem: allow registering the nvmem device before the rtc
Switch the parent of the nvmem device to the parent of the rtc device so it
can be registered before the RTC.

This is a small change in the ABI as the nvmem moves out of the
/sys/class/rtc/rtcX folder to be under the parent device folder (that is
where the previous nvram files where registered).

However, it is still available under its correct location,
/sys/bus/nvmem/devices which is the one that should be used by userspace
applications.

The other benefit is that the nvmem device can stay registered even if the
rtc registration fails. Or it is possible to not register the rtc if the
nvmem registration failed.

Finally, it makes a lot of sense for devices that actually have different
i2c or spi addresses for the RTC and the EEPROM. That is basically how it
would end up when using MFD or even completely separate devices.

Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
2018-03-01 10:49:14 +01:00
Alexandre Belloni ab3ea36eda rtc: nvmem: disallow registering nvmem more than once
Make rtc_nvmem_register return -EBUSY when an nvmem is already registered
for that RTC.

Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
2018-02-14 20:58:16 +01:00
Alexandre Belloni 2cc8212198 rtc: nvmem: return error values
In case of error, make rtc_nvmem_register() able to return an error value
to its caller.

Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
2018-02-14 20:58:13 +01:00
Alexandre Belloni 4cce9d3988 rtc: nvmem: pass nvmem_config to rtc_nvmem_register()
To be able to remove nvmem_config from struct rtc_device, pass it as a
parameter to rtc_nvmem_register.

Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
2018-02-14 20:58:11 +01:00
Alexandre Belloni 697e5a47aa rtc: add generic nvmem support
Many RTCs have an on board non volatile storage. It can be battery backed
RAM or an EEPROM. Use the nvmem subsystem to export it to both userspace
and in-kernel consumers.

This stays compatible with the previous (non documented) ABI that was using
/sys/class/rtc/rtcx/device/nvram to export that memory. But will warn about
the deprecation.

Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2017-07-07 13:14:14 +02:00