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path: root/drivers/rtc/rtc-tegra.c
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2017-04-21rtc: tegra: Implement clock handlingThierry Reding
commit 5fa4086987506b2ab8c92f8f99f2295db9918856 upstream. Accessing the registers of the RTC block on Tegra requires the module clock to be enabled. This only works because the RTC module clock will be enabled by default during early boot. However, because the clock is unused, the CCF will disable it at late_init time. This causes the RTC to become unusable afterwards. This can easily be reproduced by trying to use the RTC: $ hwclock --rtc /dev/rtc1 This will hang the system. I ran into this by following up on a report by Martin Michlmayr that reboot wasn't working on Tegra210 systems. It turns out that the rtc-tegra driver's ->shutdown() implementation will hang the CPU, because of the disabled clock, before the system can be rebooted. What confused me for a while is that the same driver is used on prior Tegra generations where the hang can not be observed. However, as Peter De Schrijver pointed out, this is because on 32-bit Tegra chips the RTC clock is enabled by the tegra20_timer.c clocksource driver, which uses the RTC to provide a persistent clock. This code is never enabled on 64-bit Tegra because the persistent clock infrastructure does not exist on 64-bit ARM. The proper fix for this is to add proper clock handling to the RTC driver in order to ensure that the clock is enabled when the driver requires it. All device trees contain the clock already, therefore no additional changes are required. Reported-by: Martin Michlmayr <tbm@cyrius.com> Acked-By Peter De Schrijver <pdeschrijver@nvidia.com> Signed-off-by: Thierry Reding <treding@nvidia.com> Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com> [bwh: Backported to 4.9: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-04-15rtc: remove use of seq_printf return valueJoe Perches
The seq_printf return value, because it's frequently misused, will eventually be converted to void. See: commit 1f33c41c03da ("seq_file: Rename seq_overflow() to seq_has_overflowed() and make public") Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-10-20rtc: drop owner assignment from platform_driversWolfram Sang
A platform_driver does not need to set an owner, it will be populated by the driver core. Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2013-05-18drivers/rtc: don't check resource with devm_ioremap_resourceWolfram Sang
devm_ioremap_resource does sanity checks on the given resource. No need to duplicate this in the driver. Signed-off-by: Wolfram Sang <wsa@the-dreams.de> Acked-by: Stephen Warren <swarren@nvidia.com>
2013-04-29drivers/rtc/rtc-tegra.c: use managed rtc_device_register()Laxman Dewangan
Use devm_rtc_device_register() for registering RTC device. This will reduce the code for unregistering RTC device in cleanup path and remove the implementation of remove callback of platform driver. Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com> Reviewed-by: Thierry Reding <thierry.reding@avionic-design.de> Reviewed-by: Stephen Warren <swarren@nvidia.com> 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>
2013-04-29drivers/rtc/rtc-tegra.c: set irq name as device nameLaxman Dewangan
The irq name of tegra rtc shows as "rtc alarm" which actually does not reflect the name related to driver. Passing the device name to have the irq names with driver name. Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com> Reviewed-by: Thierry Reding <thierry.reding@avionic-design.de> Reviewed-by: Stephen Warren <swarren@nvidia.com> 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>
2013-04-29drivers/rtc/rtc-tegra.c: use struct dev_pm_ops for power managementLaxman Dewangan
Make the Tegra RTC controller driver define its PM callbacks through a struct dev_pm_ops object rather than by using legacy PM hooks in struct platform_driver. Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com> Reviewed-by: Thierry Reding <thierry.reding@avionic-design.de> Reviewed-by: Stephen Warren <swarren@nvidia.com> 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>
2013-04-29drivers/rtc/rtc-tegra.c: protect suspend/resume callbacks with CONFIG_PM_SLEEPLaxman Dewangan
CONFIG_PM doesn't actually enable any of the PM callbacks, it only allows to enable CONFIG_PM_SLEEP and CONFIG_PM_RUNTIME. This means if CONFIG_PM is used to protect system sleep callbacks then it may end up unreferenced if only runtime PM is enabled. Hence protecting sleep callbacks with CONFIG_PM_SLEEP. Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com> Reviewed-by: Thierry Reding <thierry.reding@avionic-design.de> Reviewed-by: Stephen Warren <swarren@nvidia.com> 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>
2013-04-29rtc: rtc-tegra: use module_platform_driver_probe()Jingoo Han
Use module_platform_driver_probe() macro which makes the code smaller and simpler. Signed-off-by: Jingoo Han <jg1.han@samsung.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-04-29rtc: rtc-tegra: add __init/__exit annotationJingoo Han
When platform_driver_probe() is used, bind/unbind via sysfs is disabled. Thus, __init/__exit annotations can be added to probe()/remove(). Signed-off-by: Jingoo Han <jg1.han@samsung.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-01-22rtc: Convert to devm_ioremap_resource()Thierry Reding
Convert all uses of devm_request_and_ioremap() to the newly introduced devm_ioremap_resource() which provides more consistent error handling. devm_ioremap_resource() provides its own error messages so all explicit error messages can be removed from the failure code paths. Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Cc: Alessandro Zummo <a.zummo@towertech.it> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-01-04drivers/rtc/rtc-tegra.c: convert to DT driverJoseph Lo
After Kernel 3.7, the Tegra device will only support booting with DT. The legacy Tegra RTC platform driver will not work anymore. This patch converts the driver to support DT. Signed-off-by: Joseph Lo <josephl@nvidia.com> Cc: Stephen Warren <swarren@wwwdotorg.org> Cc: Joseph Lo <josephl@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-01-03Drivers: rtc: remove __dev* attributes.Greg Kroah-Hartman
CONFIG_HOTPLUG is going away as an option. As a result, the __dev* markings need to be removed. This change removes the use of __devinit, __devexit_p, __devinitdata, __devinitconst, and __devexit from these drivers. Based on patches originally written by Bill Pemberton, but redone by me in order to handle some of the coding style issues better, by hand. Cc: Bill Pemberton <wfp5p@virginia.edu> Cc: Alessandro Zummo <a.zummo@towertech.it> Cc: Srinidhi Kasagar <srinidhi.kasagar@stericsson.com> Cc: Linus Walleij <linus.walleij@linaro.org> Cc: Mike Frysinger <vapier.adi@gmail.com> Cc: Wan ZongShun <mcuos.com@gmail.com> Cc: Guan Xuetao <gxt@mprc.pku.edu.cn> Cc: Mark Brown <broonie@opensource.wolfsonmicro.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-05-29drivers/rtc/rtc-tegra.c: clean up probe/remove routinesHannu Heikkinen
Use the devres managed resource functions in the probe routine. Also affects the remove routine where the previously used free and release functions are not needed. The devm_* functions eliminate the need for manual resource releasing and simplify error handling. Resources allocated by devm_* are freed automatically on driver detach. Signed-off-by: Hannu Heikkinen <ext-hannu.m.heikkinen@nokia.com> Acked-by: Stephen Warren <swarren@wwwdotorg.org> Cc: Alessandro Zummo <a.zummo@towertech.it> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-07-25drivers/rtc/rtc-tegra.c: properly initialize spinlockUwe Kleine-König
Using __SPIN_LOCK_UNLOCKED for a dynamically allocated lock is wrong and breaks the build with PREEMPT_RT_FULL. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Cc: Andrew Chew <achew@nvidia.com> Cc: <stable@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-22rtc: add real-time clock driver for NVIDIA TegraAndrew Chew
This is a platform driver that supports the built-in real-time clock on Tegra SOCs. Signed-off-by: Andrew Chew <achew@nvidia.com> Acked-by: Alessandro Zummo <a.zummo@towertech.it> Acked-by: Wan ZongShun <mcuos.com@gmail.com> Acked-by: Jon Mayo <jmayo@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>