Commit Graph

45 Commits

Author SHA1 Message Date
Mian Yousaf Kaukab 2f86198467 rtc: pcf2127: handle timestamp interrupts
commit 03623b4b04 ("rtc: pcf2127: add tamper detection support")
added support for timestamp interrupts. However they are not being
handled in the irq handler. If a timestamp interrupt occurs it
results in kernel disabling the interrupt and displaying the call
trace:

[  121.145580] irq 78: nobody cared (try booting with the "irqpoll" option)
...
[  121.238087] [<00000000c4d69393>] irq_default_primary_handler threaded [<000000000a90d25b>] pcf2127_rtc_irq [rtc_pcf2127]
[  121.248971] Disabling IRQ #78

Handle timestamp interrupts in pcf2127_rtc_irq(). Save time stamp
before clearing TSF1 and TSF2 flags so that it can't be overwritten.
Set a flag to mark if the timestamp is valid and only report to sysfs
if the flag is set. To mimic the hardware behavior, don’t save
another timestamp until the first one has been read by the userspace.

However, if the alarm irq is not configured, keep the old way of
handling timestamp interrupt in the timestamp0 sysfs calls.

Signed-off-by: Mian Yousaf Kaukab <ykaukab@suse.de>
Reviewed-by: Bruno Thomsen <bruno.thomsen@gmail.com>
Tested-by: Bruno Thomsen <bruno.thomsen@gmail.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20210629150643.31551-1-ykaukab@suse.de
2021-07-10 02:58:31 +02:00
Fabio Estevam 836e9ea3cc rtc: pcf2127: Fix the datasheet URL
The current datasheet URL is no longer valid.

Replace with a valid one.

Signed-off-by: Fabio Estevam <festevam@gmail.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20210603143447.2223353-1-festevam@gmail.com
2021-06-20 23:48:35 +02:00
Biwen Li 2843d565dd rtc: pcf2127: properly set flag WD_CD for rtc chips(pcf2129, pca2129)
Properly set flag WD_CD for rtc chips(pcf2129, pca2129)

Signed-off-by: Biwen Li <biwen.li@nxp.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20201202031840.15582-1-biwen.li@oss.nxp.com
2021-02-13 22:38:13 +01:00
Philipp Rosenberger 15f57b3e31 rtc: pcf2127: Run a OTP refresh if not done before
The datasheet of the PCF2127 states, it is recommended to process an OTP
refresh once the power is up and the oscillator is operating stable. The
OTP refresh takes less than 100 ms to complete.

Signed-off-by: Philipp Rosenberger <p.rosenberger@kunbus.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20210118085752.5759-3-p.rosenberger@kunbus.com
2021-01-26 00:27:06 +01:00
Philipp Rosenberger b9ac079abe rtc: pcf2127: Disable Power-On Reset Override
To resume normal operation after a total power loss (no or empty
battery) the "Power-On Reset Override (PORO)" facility needs to be
disabled.

The register reset value sets the PORO enabled and the data sheet
recommends setting it to disabled for normal operation.

From what I've seen on the PCF2127 and PCF2129 there is no event
generated at the interrupt pin (INT), as long the PORO bit is set. This
behavior is not documented in the manual.

Signed-off-by: Philipp Rosenberger <p.rosenberger@kunbus.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20210118085752.5759-2-p.rosenberger@kunbus.com
2021-01-26 00:26:16 +01:00
Alexandre Belloni 25cbe9c8d9 rtc: pcf2127: remove pcf2127_rtc_alrm_ops
Move the alarm callbacks in pcf2127_rtc_ops and use RTC_FEATURE_ALARM to
signal to the core whether alarms are available instead of having a
supplementary struct rtc_class_ops without alarm callbacks.

Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20210110231752.1418816-8-alexandre.belloni@bootlin.com
2021-01-16 23:19:26 +01:00
Uwe Kleine-König 71ac13457d rtc: pcf2127: only use watchdog when explicitly available
Most boards using the pcf2127 chip (in my bubble) don't make use of the
watchdog functionality and the respective output is not connected. The
effect on such a board is that there is a watchdog device provided that
doesn't work.

So only register the watchdog if the device tree has a "reset-source"
property.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
[RV: s/has-watchdog/reset-source/]
Signed-off-by: Rasmus Villemoes <rasmus.villemoes@prevas.dk>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20201218101054.25416-3-rasmus.villemoes@prevas.dk
2020-12-19 01:57:44 +01:00
Bartosz Golaszewski fdcfd85433 rtc: rework rtc_register_device() resource management
rtc_register_device() is a managed interface but it doesn't use devres
by itself - instead it marks an rtc_device as "registered" and the devres
callback for devm_rtc_allocate_device() takes care of resource release.

This doesn't correspond with the design behind devres where managed
structures should not be aware of being managed. The correct solution
here is to register a separate devres callback for unregistering the
device.

While at it: rename rtc_register_device() to devm_rtc_register_device()
and add it to the list of managed interfaces in devres.rst. This way we
can avoid any potential confusion of driver developers who may expect
there to exist a corresponding unregister function.

Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20201109163409.24301-8-brgl@bgdev.pl
2020-11-19 12:50:12 +01:00
Bartosz Golaszewski 3a905c2d95 rtc: add devm_ prefix to rtc_nvmem_register()
rtc_nvmem_register() is a managed interface. It doesn't require any
release function to be called at driver detach. To avoid confusing
driver authors, let's rename it to devm_rtc_nvmem_register() and add it
to the list of managed interfaces in Documentation/.

Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20201109163409.24301-6-brgl@bgdev.pl
2020-11-19 12:50:11 +01:00
Dan Carpenter ba1c30bf3f rtc: pcf2127: fix pcf2127_nvmem_read/write() returns
These functions should return zero on success.  Non-zero returns are
treated as error.  On some paths, this doesn't matter but in
nvmem_cell_read() a non-zero return would be passed to ERR_PTR() and
lead to an Oops.

Fixes: d6c3029f32 ("rtc: pcf2127: add support for accessing internal static RAM")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20201022070451.GA2817669@mwanda
2020-10-27 12:23:23 +01:00
Uwe Kleine-König 5d78533a0c rtc: pcf2127: move watchdog initialisation to a separate function
The obvious advantages are:

 - The linker can drop the watchdog functions if CONFIG_WATCHDOG is off.
 - All watchdog stuff grouped together with only a single function call
   left in generic code.
 - Watchdog register is only read when it is actually used.
 - Less #ifdefery

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20200924105256.18162-2-u.kleine-koenig@pengutronix.de
2020-10-27 12:18:28 +01:00
Biwen Li 35425bafc7 rtc: pcf2127: fix a bug when not specify interrupts property
Fix a bug when not specify interrupts property in dts
as follows,
    rtc-pcf2127-i2c 1-0051: failed to request alarm irq
    rtc-pcf2127-i2c: probe of 1-0051 failed with error -22

Signed-off-by: Biwen Li <biwen.li@nxp.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20200915073213.12779-1-biwen.li@oss.nxp.com
2020-09-15 12:25:44 +02:00
Alexandre Belloni 27006416be rtc: pcf2127: fix alarm handling
Fix multiple issues when handling alarms:
 - Use threaded interrupt to avoid scheduling when atomic
 - Stop matching on week day as it may not be set correctly
 - Avoid parsing the DT interrupt and use what is provided by the i2c or
   spi subsystem
 - Avoid returning IRQ_NONE in case of error in the interrupt handler
 - Never write WDTF as specified in the datasheet
 - Set uie_unsupported, as for the pcf85063, setting alarms every seconds
   is not working correctly and confuses the RTC.

Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20200812085114.474903-1-alexandre.belloni@bootlin.com
2020-08-12 11:48:29 +02:00
Liam Beguin 8a914bac44 rtc: pcf2127: add alarm support
Add alarm support for the pcf2127 RTC chip family.
Tested on pca2129.

Signed-off-by: Liam Beguin <lvb@xiphos.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Reviewed-by: Bruno Thomsen <bruno.thomsen@gmail.com>
Link: https://lore.kernel.org/r/20200630024211.12782-3-liambeguin@gmail.com
2020-08-12 11:37:37 +02:00
Liam Beguin 985b30dbe2 rtc: pcf2127: add pca2129 device id
The PCA2129 is the automotive grade version of the PCF2129.
add it to the list of compatibles.

Signed-off-by: Liam Beguin <lvb@xiphos.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Reviewed-by: Bruno Thomsen <bruno.thomsen@gmail.com>
Link: https://lore.kernel.org/r/20200630024211.12782-2-liambeguin@gmail.com
2020-08-12 11:37:37 +02:00
Bruno Thomsen 4601e24a6f rtc: pcf2127: watchdog: handle nowayout feature
Driver does not use module parameter for nowayout, so it need to
statically initialize status variable of the watchdog_device based
on CONFIG_WATCHDOG_NOWAYOUT.

Signed-off-by: Bruno Thomsen <bruno.thomsen@gmail.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Acked-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20200604162602.76524-1-bruno.thomsen@gmail.com
2020-06-06 00:34:16 +02:00
Alexandre Belloni 7d65cf8c1f rtc: pcf2127: report battery switch over
Add support for the RTC_VL_BACKUP_SWITCH flag to report battery switch over
events.

Link: https://lore.kernel.org/r/20200511140335.799133-1-alexandre.belloni@bootlin.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
2020-05-11 16:04:44 +02:00
Alexandre Belloni 040e6dc091 rtc: pcf2127: set regmap max_register
Set regmap max_register to ease debugging and enforce the register range.

Link: https://lore.kernel.org/r/20200505201310.255145-4-alexandre.belloni@bootlin.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
2020-05-11 16:04:42 +02:00
Alexandre Belloni 664eaf033f rtc: pcf2127: remove unnecessary #ifdef
There is not point in setting .ioctl to NULL when CONFIG_RTC_INTF_DEV is
not defined because it would not be called anyway.

Link: https://lore.kernel.org/r/20200505201310.255145-3-alexandre.belloni@bootlin.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
2020-05-11 16:04:40 +02:00
Alexandre Belloni b139bb5c26 rtc: pcf2127: let the core handle rtc range
Let the core handle offsetting and windowing the RTC range.

Link: https://lore.kernel.org/r/20200505201310.255145-2-alexandre.belloni@bootlin.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
2020-05-11 16:04:38 +02:00
Alexandre Belloni af4273116d rtc: pcf2127: return meaningful value for RTC_VL_READ
PCF2127_BIT_CTRL3_BLF indicates the battery is low and needs to be replaced
soon.

Link: https://lore.kernel.org/r/20191214220259.621996-5-alexandre.belloni@bootlin.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
2019-12-18 10:37:23 +01:00
Martin Hundebøll 62409933b8 rtc: pcf2127: handle boot-enabled watchdog feature
Linux should handle when the pcf2127 watchdog feature is enabled by the
bootloader. This is done by checking the watchdog timer value during
init, and set the WDOG_HW_RUNNING flag if the value differs from zero.

Signed-off-by: Martin Hundebøll <martin@geanix.com>
Acked-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20191021080838.2789-1-martin@geanix.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
2019-10-21 10:24:18 +02:00
Bruno Thomsen 28abbba36a rtc: pcf2127: bugfix: watchdog build dependency
Disable watchdog registation when kernel is build without
watchdog functionality, and enable watchdog core otherwise.
This removes compile errors like the one below:

drivers/rtc/rtc-pcf2127.o: in function `pcf2127_probe.constprop.3':
rtc-pcf2127.c:(.text.unlikely+0x2c8): undefined reference to
`devm_watchdog_register_device'

Watchdog feature in chip will always be configured as
this is safe to do in both cases and minimize code churn.

Reported-by: Hulk Robot <hulkci@huawei.com>
Reported-by: YueHaibing <yuehaibing@huawei.com>
Fixes: bbc597561ce1 ("rtc: pcf2127: add watchdog feature support")
Signed-off-by: Bruno Thomsen <bruno.thomsen@gmail.com>
Link: https://lore.kernel.org/r/20190827143656.4734-1-bruno.thomsen@gmail.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
2019-08-27 18:24:15 +02:00
Bruno Thomsen 03623b4b04 rtc: pcf2127: add tamper detection support
Add support for integrated tamper detection function in both PCF2127 and
PCF2129 chips. This patch implements the feature by adding an additional
timestamp0 file to sysfs device path. This file contains seconds since
epoch, if an event occurred, or is empty, if none occurred.
Interface should match ISL1208 and RV3028 RTC drivers.

Signed-off-by: Bruno Thomsen <bruno.thomsen@gmail.com>
Link: https://lore.kernel.org/r/20190822131936.18772-5-bruno.thomsen@gmail.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
2019-08-27 18:24:15 +02:00
Bruno Thomsen 0e735eaae1 rtc: pcf2127: add watchdog feature support
Add partial support for the watchdog functionality of
both PCF2127 and PCF2129 chips.

The programmable watchdog timer is currently using a fixed
clock source of 1Hz. This result in a selectable range of
1-255 seconds, which covers most embedded Linux use-cases.

Clock sources of 4096Hz, 64Hz and 1/60Hz is mostly useful
in MCU use-cases.

Countdown timer not available when using watchdog feature.

Signed-off-by: Bruno Thomsen <bruno.thomsen@gmail.com>
Acked-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20190822131936.18772-4-bruno.thomsen@gmail.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
2019-08-27 18:24:15 +02:00
Bruno Thomsen 7f43020e3b rtc: pcf2127: bugfix: read rtc disables watchdog
The previous fix listed bulk read of registers as root cause of
accendential disabling of watchdog, since the watchdog counter
register (WD_VAL) was zeroed.

Fixes: 3769a375ab rtc: pcf2127: bulk read only date and time registers.

Tested with the same PCF2127 chip as Sean reveled root cause
of WD_VAL register value zeroing was caused by reading CTRL2
register which is one of the watchdog feature control registers.

So the solution is to not read the first two control registers
(CTRL1 and CTRL2) in pcf2127_rtc_read_time as they are not
needed anyway. Size of local buf variable is kept to allow
easy usage of register defines to improve readability of code.

Debug trace line was updated after CTRL1 and CTRL2 are no longer
read from the chip. Also replaced magic numbers in buf access
with register defines.

Signed-off-by: Bruno Thomsen <bruno.thomsen@gmail.com>
Link: https://lore.kernel.org/r/20190822131936.18772-3-bruno.thomsen@gmail.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
2019-08-23 16:20:50 +02:00
Bruno Thomsen bbfe3a7a1d rtc: pcf2127: cleanup register and bit defines
Cleanup of defines to follow kernel coding style and increase code
readability by using same register and bit define style.

Change PCF2127_REG_RAM_{addr_MSB,wrt_cmd,rd_cmd} to upper case as
kernel coding guide section 12 'Macros, Enums and RTL' states
"Names of macros defining constants and labels in enums are capitalized".

Improve readability of RAM register comment by making whole sentences.

Remove parentheses from register defines as they are only used
for expressions and not constants.

As there are no clear style for name of registers and bits in the
kernel drivers, I suggest the following for at least this driver,
but hopefully also other RTC drivers.

Register name should follow this convention:
[chip]_REG_[reg name] 0xXX

Bit name should follow this convention, so it clearly states which
chip register it's part of:
[chip]_BIT_[reg name]_[bit name] BIT(X)

Additionally I suggest bit defines are always placed right below
its corresponding register define and using an extra tab indentation
for the BIT(X) part. This will visually make it easy to see that bit
defines are part of the complete register definition.

Rename PCF2127_OSF to PCF2127_BIT_SC_OSF and move it right below
PCF2127_REG_SC. This will improve readability of bit checks as it's
easy to verify that it uses the correct register.

Move end of line comments above register defines as it's more like
a heading for 1 register define and up to 8 bit defines or a
collection of registers that are close related like timestamp
split across 6 registers.

Signed-off-by: Bruno Thomsen <bruno.thomsen@gmail.com>
Link: https://lore.kernel.org/r/20190822131936.18772-2-bruno.thomsen@gmail.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
2019-08-23 16:20:50 +02:00
Bruno Thomsen e788771cac rtc: pcf2127: convert to devm_rtc_allocate_device
This allows further improvement of the driver.

Signed-off-by: Bruno Thomsen <bruno.thomsen@gmail.com>
Link: https://lore.kernel.org/r/20190822131936.18772-1-bruno.thomsen@gmail.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
2019-08-23 16:20:50 +02:00
Thomas Gleixner d2912cb15b treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500
Based on 2 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license version 2 as
  published by the free software foundation

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license version 2 as
  published by the free software foundation #

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-only

has been chosen to replace the boilerplate/reference in 4122 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Enrico Weigelt <info@metux.net>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-19 17:09:55 +02:00
Xulin Sun 9bde0afb7a rtc: pcf2127: fix a kmemleak caused in pcf2127_i2c_gather_write
pcf2127_i2c_gather_write() allocates memory as local variable
for i2c_master_send(), after finishing the master transfer,
the allocated memory should be freed. The kmemleak is reported:

unreferenced object 0xffff80231e7dba80 (size 64):
  comm "hwclock", pid 27762, jiffies 4296880075 (age 356.944s)
  hex dump (first 32 bytes):
    03 00 12 03 19 02 11 13 00 80 98 18 00 00 ff ff ................
    00 50 00 00 00 00 00 00 02 00 00 00 00 00 00 00 .P..............
  backtrace:
    [<ffff000008221398>] create_object+0xf8/0x278
    [<ffff000008a96264>] kmemleak_alloc+0x74/0xa0
    [<ffff00000821070c>] __kmalloc+0x1ac/0x348
    [<ffff0000087ed1dc>] pcf2127_i2c_gather_write+0x54/0xf8
    [<ffff0000085fd9d4>] _regmap_raw_write+0x464/0x850
    [<ffff0000085fe3f4>] regmap_bulk_write+0x1a4/0x348
    [<ffff0000087ed32c>] pcf2127_rtc_set_time+0xac/0xe8
    [<ffff0000087eaad8>] rtc_set_time+0x80/0x138
    [<ffff0000087ebfb0>] rtc_dev_ioctl+0x398/0x610
    [<ffff00000823f2c0>] do_vfs_ioctl+0xb0/0x848
    [<ffff00000823fae4>] SyS_ioctl+0x8c/0xa8
    [<ffff000008083ac0>] el0_svc_naked+0x34/0x38
    [<ffffffffffffffff>] 0xffffffffffffffff

Signed-off-by: Xulin Sun <xulin.sun@windriver.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
2018-11-07 17:13:56 +01:00
Uwe Kleine-König d6c3029f32 rtc: pcf2127: add support for accessing internal static RAM
The PCF2127 has 512 bytes of internal static RAM and this patch expands
the driver to access this memory.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
2018-07-11 20:41:22 +02:00
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
Sean Nyekjaer 3769a375ab rtc: pcf2127: bulk read only date and time registers.
Read control registers one by one and bulk read time registers.
This fixes when the clock is read, the watchdog counter register is zeroed.

Signed-off-by: Sean Nyekjaer <sean.nyekjaer@prevas.dk>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2017-02-23 18:38:54 +01:00
Akinobu Mita cee2cc2155 rtc: pcf2127: add pcf2129 device id
There are only a few differences between PCF2127 and PCF2129 (PCF2127
has 512 bytes of general purpose SRAM and count-down timer).

The rtc-pcf2127 driver currently doesn't use the PCF2127 specific
functionality and Kconfig help text already says this driver supports
PCF2127/29, so we can simply add pcf2129 to device id list.

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2016-03-14 17:08:41 +01:00
Akinobu Mita 9408ec1af8 rtc: pcf2127: add support for spi interface
pcf2127 has selectable I2C-bus and SPI-bus interface support.

This adds support for SPI interface.

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2016-03-14 17:08:41 +01:00
Akinobu Mita 907b326258 rtc: pcf2127: convert to use regmap
pcf2127 has selectable I2C-bus and SPI-bus interface support.
Currently rtc-pcf2127 driver only supports I2C.

This is preparation for support for SPI interface.

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2016-03-14 17:08:40 +01:00
Uwe Kleine-König 3cfcb50b48 rtc: pcf2127: remove useless driver version
A driver version is only really sensible for oot drivers. Also the
dev_info about having found a chip only signals that allocating the
driver data succeeded and so isn't worth much.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2015-11-08 14:12:28 +01:00
Uwe Kleine-König f97cfddc88 rtc: pcf2127: fix reading uninitialized value on RTC_READ_VL ioctl
The flag reported on the RTC_READ_VL ioctl is only initialized when the
date is read out. So the voltage low value doesn't represent reality but
the status at the time the date was read (or 0 if the date was not read
yet).

Moreover when userspace requests a value via an ioctl there is no added
benefit to also make a prosa representation of this (and other) values
appear in the kernel log so remove the calls to dev_info and the driver
data members to track their state.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2015-11-08 14:12:27 +01:00
Uwe Kleine-König 4d8318bc97 rtc: pcf2127: make module license match the file header
The header of the pcf2127 driver specifies GPL v2 only as license, so
use "GPL v2" as module license specifier instead of "GPL" as the latter
means "GNU Public License v2 or later".

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2015-11-03 00:50:46 +01:00
Krzysztof Kozlowski b28845433e rtc: Drop owner assignment from i2c_driver
i2c_driver does not need to set an owner because i2c_register_driver()
will set it.

Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2015-09-05 13:19:06 +02:00
Andrea Scian 653ebd75e9 rtc: pcf2127: use OFS flag to detect unreliable date and warn the user
The PCF2127 datasheet states that it's wrong to say that the date in
unreliable if BLF (battery low flag) is set but instead, OSF (seconds
register) should be used to check if oscillator, for any reason, stopped.
Battery may be low (usually below 2V5 threshold) but the date may be anyway
correct (typically date is unreliable when input voltage is below 1V2).

Signed-off-by: Andrea Scian <andrea.scian@dave.eu>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2015-09-05 13:19:06 +02:00
Andrea Scian 821f51c4da rtc: use rtc_valid_tm() error code when reading date/time
There's a wrong comment in some RTC drivers that say it's better to ignore
rtc_valid_tm() when reading RTC timestamp. However this is wrong and is
better to return to the userspace the error if timestamp is not valid.

Signed-off-by: Andrea Scian <andrea.scian@dave.eu>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2015-09-05 13:19:06 +02:00
Duan Jiong 7ab26cd1ef drivers/rtc/rtc-pcf2127.c: replace IS_ERR and PTR_ERR with PTR_ERR_OR_ZERO
Fix a coccinelle error regarding usage of IS_ERR and PTR_ERR instead of
PTR_ERR_OR_ZERO.

Signed-off-by: Duan Jiong <duanj.fnst@cn.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-01-23 16:37:00 -08:00
Sachin Kamat 4540bae9cd drivers/rtc/rtc-pcf2127.c: remove empty function
The 'remove' function is empty and does not do anything.  Delete it.

Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-11 15:58:53 -07:00
Renaud Cerrato 18cb6368f0 rtc: add NXP PCF2127 support (i2c)
Added support for NXP PCF2127 RTC (i2c).

[akpm@linux-foundation.org: fix typo, fix warnings]
Signed-off-by: Renaud Cerrato <r.cerrato@til-technologies.fr>
Cc: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-07-03 16:08:00 -07:00