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path: root/drivers/rtc/rtc-m41t80.c
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* rtc: m41t80: remove useless indirectionAlexandre Belloni2018-03-171-15/+5
| | | | | | | m41t80_get_datetime and m41t80_set_datetime are only used after casting dev to an i2c_client. Remove that useless indirection. Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
* rtc: m41t80: fix race conditionsAlexandre Belloni2018-03-171-7/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The IRQ is requested before the struct rtc is allocated and registered, but this struct is used in the IRQ handler, leading to: Unable to handle kernel NULL pointer dereference at virtual address 0000017c pgd = a38a2f9b [0000017c] *pgd=00000000 Internal error: Oops: 5 [#1] ARM Modules linked in: CPU: 0 PID: 613 Comm: irq/48-m41t80 Not tainted 4.16.0-rc1+ #42 Hardware name: Atmel SAMA5 PC is at mutex_lock+0x14/0x38 LR is at m41t80_handle_irq+0x1c/0x9c pc : [<c06e864c>] lr : [<c04b70f0>] psr: 20000013 sp : dec73f30 ip : 00000000 fp : dec56d98 r10: df437cf0 r9 : c0a03008 r8 : c0145ffc r7 : df5c4300 r6 : dec568d0 r5 : df593000 r4 : 0000017c r3 : df592800 r2 : 60000013 r1 : df593000 r0 : 0000017c Flags: nzCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none Control: 10c53c7d Table: 20004059 DAC: 00000051 Process irq/48-m41t80 (pid: 613, stack limit = 0xb52d091e) Stack: (0xdec73f30 to 0xdec74000) 3f20: dec56840 df5c4300 00000001 df5c4300 3f40: c0145ffc c0146018 dec56840 ffffe000 00000001 c0146290 dec567c0 00000000 3f60: c0146084 ed7c9a62 c014615c dec56d80 dec567c0 00000000 dec72000 dec56840 3f80: c014615c c012ffc0 dec72000 dec567c0 c012fe80 00000000 00000000 00000000 3fa0: 00000000 00000000 00000000 c01010e8 00000000 00000000 00000000 00000000 3fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 3fe0: 00000000 00000000 00000000 00000000 00000013 00000000 29282726 2d2c2b2a [<c06e864c>] (mutex_lock) from [<c04b70f0>] (m41t80_handle_irq+0x1c/0x9c) [<c04b70f0>] (m41t80_handle_irq) from [<c0146018>] (irq_thread_fn+0x1c/0x54) [<c0146018>] (irq_thread_fn) from [<c0146290>] (irq_thread+0x134/0x1c0) [<c0146290>] (irq_thread) from [<c012ffc0>] (kthread+0x140/0x148) [<c012ffc0>] (kthread) from [<c01010e8>] (ret_from_fork+0x14/0x2c) Exception stack(0xdec73fb0 to 0xdec73ff8) 3fa0: 00000000 00000000 00000000 00000000 3fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 3fe0: 00000000 00000000 00000000 00000000 00000013 00000000 Code: e3c33d7f e3c3303f f5d0f000 e593300c (e1901f9f) ---[ end trace 22b027302eb7c604 ]--- genirq: exiting task "irq/48-m41t80" (613) is an active IRQ thread (irq 48) Also, there is another possible race condition. The probe function is not allowed to fail after the RTC is registered because the following may happen: CPU0: CPU1: sys_load_module() do_init_module() do_one_initcall() cmos_do_probe() rtc_device_register() __register_chrdev() cdev->owner = struct module* open("/dev/rtc0") rtc_device_unregister() module_put() free_module() module_free(mod->module_core) /* struct module *module is now freed */ chrdev_open() spin_lock(cdev_lock) cdev_get() try_module_get() module_is_live() /* dereferences already freed struct module* */ Switch to devm_rtc_allocate_device/rtc_register_device to allocate the rtc before requesting the IRQ and register it as late as possible. Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
* rtc: m41t80: move m41t80_rtc_mutex to the block where it is usedSebastian Andrzej Siewior2018-03-171-1/+1
| | | | | | | | | | | Without CONFIG_RTC_DRV_M41T80_WDT the compiler complains: |drivers/rtc/rtc-m41t80.c:76 ‘m41t80_rtc_mutex’ defined but not used [-Wunused-variable] Move the variable to the block where it is used. Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
* rtc: stop validating rtc_time in .read_timeAlexandre Belloni2018-03-021-1/+1
| | | | | | | 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>
* rtc: m41t80: remove unneeded checks from m41t80_sqw_set_rateTroy Kisky2017-11-081-11/+6
| | | | | | | | | | | | | | | | | | m41t80_sqw_set_rate will be called with the result from m41t80_sqw_round_rate, so might as well make m41t80_sqw_set_rate(n) same as m41t80_sqw_set_rate(m41t80_sqw_round_rate(n)) As Russell King wrote[1], "clk_round_rate() is supposed to tell you what you end up with if you ask clk_set_rate() to set the exact same value you passed in - but clk_round_rate() won't modify the hardware." [1] http://lists.infradead.org/pipermail/linux-arm-kernel/2012-January/080175.html Signed-off-by: Troy Kisky <troy.kisky@boundarydevices.com> Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
* rtc: m41t80: avoid i2c read in m41t80_sqw_is_preparedTroy Kisky2017-11-081-9/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | This is a little more efficient and avoids the warning WARNING: possible circular locking dependency detected 4.14.0-rc7-00010 #16 Not tainted ------------------------------------------------------ kworker/2:1/70 is trying to acquire lock: (prepare_lock){+.+.}, at: [<c049300c>] clk_prepare_lock+0x80/0xf4 but task is already holding lock: (i2c_register_adapter){+.+.}, at: [<c0690b04>] i2c_adapter_lock_bus+0x14/0x18 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (i2c_register_adapter){+.+.}: rt_mutex_lock+0x44/0x5c i2c_adapter_lock_bus+0x14/0x18 i2c_transfer+0xa8/0xbc i2c_smbus_xfer+0x20c/0x5d8 i2c_smbus_read_byte_data+0x38/0x48 m41t80_sqw_is_prepared+0x18/0x28 Signed-off-by: Troy Kisky <troy.kisky@boundarydevices.com> Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
* rtc: m41t80: avoid i2c read in m41t80_sqw_recalc_rateTroy Kisky2017-11-081-11/+17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | This is a little more efficient, and avoids the warning WARNING: possible circular locking dependency detected 4.14.0-rc7-00007 #14 Not tainted ------------------------------------------------------ alsactl/330 is trying to acquire lock: (prepare_lock){+.+.}, at: [<c049300c>] clk_prepare_lock+0x80/0xf4 but task is already holding lock: (i2c_register_adapter){+.+.}, at: [<c0690ae0>] i2c_adapter_lock_bus+0x14/0x18 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (i2c_register_adapter){+.+.}: rt_mutex_lock+0x44/0x5c i2c_adapter_lock_bus+0x14/0x18 i2c_transfer+0xa8/0xbc i2c_smbus_xfer+0x20c/0x5d8 i2c_smbus_read_byte_data+0x38/0x48 m41t80_sqw_recalc_rate+0x24/0x58 Signed-off-by: Troy Kisky <troy.kisky@boundarydevices.com> Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
* rtc: m41t80: fix m41t80_sqw_round_rate return valueTroy Kisky2017-11-081-12/+7
| | | | | | | | | | | | Previously it was returning the best of 32768, 8192, 1024, 64, 2, 0 Now, best of 32768, 8192, 4096, 2048, 1024, 512, 256, 128, 64, 32, 16, 8, 4, 2, 1, 0 Signed-off-by: Troy Kisky <troy.kisky@boundarydevices.com> Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
* rtc: m41t80: m41t80_sqw_set_rate should return 0 on successTroy Kisky2017-11-081-4/+1
| | | | | | | Previously it was returning -EINVAL upon success. Signed-off-by: Troy Kisky <troy.kisky@boundarydevices.com> Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
* rtc: m41t80: remove debug sysfs attributeAlexandre Belloni2017-08-241-44/+0
| | | | | | | The last remaining sysfs attribute is undocumented and useless as it can only be used to debug the driver. Remove it. Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
* rtc: m41t80: enable wakealarm when "wakeup-source" is specifiedEric Cooper2017-08-241-6/+17
| | | | | | | Don't require an IRQ if the wakeup-source device-tree property is present. Signed-off-by: Eric Cooper <ecc@cmu.edu> Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
* rtc: m41t80: add clock provider supportGary Bisson2017-05-311-0/+172
| | | | | | | | | | | Some devices supported by the m41t80 driver have a programmable square-wave output signal (see M41T80_FEATURE_SQ). This enables to use this feature as a clock provider of common clock framework. Signed-off-by: Gary Bisson <gary.bisson@boundarydevices.com> Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
* rtc: m41t80: remove sqw sysfs entryGary Bisson2017-05-311-88/+0
| | | | | | | In order to use the proper clock framework to control this feature. Signed-off-by: Gary Bisson <gary.bisson@boundarydevices.com> Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
* rtc: m41t80: fix SQW dividers override when setting a dateGary Bisson2017-05-311-0/+12
| | | | | | | | | | | | This patch is only relevant for RTC with the SQ_ALT feature which means the clock output frequency divider is stored in the weekday register. Current implementation discards the previous dividers value and clear them as soon as the time is set. Signed-off-by: Gary Bisson <gary.bisson@boundarydevices.com> Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
* rtc: m41t80: fix SQWE override when setting an alarmGary Bisson2017-05-311-0/+3
| | | | | | | | Currently setting an alarm clears the SQWE bit which means that the clock output is disabled no matter its previous state. Signed-off-by: Gary Bisson <gary.bisson@boundarydevices.com> Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
* rtc: m41t80: Add proper compatible for rv4162Alexandre Belloni2017-04-191-0/+5
| | | | | | | The correct compatible for the rv4162 (microcrystal,rv4162) was not used upstream and so was not added by eb235c561d04e. Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
* rtc: m41t80: Add OF device ID tableJavier Martinez Canillas2017-03-091-2/+61
| | | | | | | | | | | | | The driver doesn't have a struct of_device_id table but supported devices are registered via Device Trees. This is working on the assumption that a I2C device registered via OF will always match a legacy I2C device ID and that the MODALIAS reported will always be of the form i2c:<device>. But this could change in the future so the correct approach is to have an OF device ID table if the devices are registered via OF. Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com> Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
* rtc: m41t80: add suspend handlers for alarm IRQStefan Christ2016-07-211-0/+25
| | | | | | | | Allow the alarm IRQ of RTC to be used as a wakeup source for the system suspend. Signed-off-by: Stefan Christ <s.christ@phytec.de> Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
* rtc: m41t80: make it a real error messageStefan Christ2016-07-211-1/+1
| | | | | | | | It should be a real error message, when the driver cannot enable the IRQ of the device. Signed-off-by: Stefan Christ <s.christ@phytec.de> Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
* rtc: m41t80: use devm_add_action_or_reset()Sudip Mukherjee2016-07-191-3/+2
| | | | | | | | | | If devm_add_action() fails we are explicitly calling the cleanup to free the resources allocated. Lets use the helper devm_add_action_or_reset() and return directly in case of error, as we know that the cleanup function has been already called by the helper if there was any error. Signed-off-by: Sudip Mukherjee <sudip.mukherjee@codethink.co.uk> Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
* rtc: simplify implementations of read_alarmUwe Kleine-König2016-07-091-2/+0
| | | | | | | | | | Since commit d68778b80dd7 ("rtc: initialize output parameter for read alarm to "uninitialized"") there is no need to explicitly set unsupported members to -1. So drop the respective assignments from drivers. Signed-off-by: Uwe Kleine-König <uwe@kleine-koenig.org> Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
* rtc: m41t80: handle oscillator failure bitMylène Josserand2016-05-201-2/+23
| | | | | | | | | Handle the Oscillator Failure (OF) bit on each read of date-time. If the OF is set, an error is returned (-EINVAL) instead of the date-time. The OF bit is cleared each time the date is set. Signed-off-by: Mylène Josserand <mylene.josserand@free-electrons.com> Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
* rtc: m41t80: add wakealarm functionalityMylène Josserand2016-05-201-0/+2
| | | | | | | | | To enable the wakealarm, the device must be able to wakeup. This is done by setting the device wakeup capability to true with 'device_init_wakeup' function. Signed-off-by: Mylène Josserand <mylene.josserand@free-electrons.com> Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
* rtc: m41t80: add alarm functionalityMylène Josserand2016-05-201-13/+167
| | | | | | | | | | | | Previous 'commit c3b79770e51a ("Expire alarms after the time is set")' and 'commit 48e9766726eb ("remove disabled alarm functionality")' removed the alarm support because the alarm irq was not functional. Add the alarm IRQ functionality with newer functions than previous code. Tested with 'rtctest' and the alarm is functional. Signed-off-by: Mylène Josserand <mylene.josserand@free-electrons.com> Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
* rtc: m41t80: remove warnings and replace obsolete functionMylène Josserand2016-05-201-11/+15
| | | | | | | | | | | | Replace the obsolete "simple_strtoul" function to "kstrtoul". Remove some checkpatch's errors, warnings and checks : - alignment with open parenthesis - spaces around '<' and '<<' - blank line after structure - quoted string split across lines Signed-off-by: Mylène Josserand <mylene.josserand@free-electrons.com> Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
* rtc: m41t80: add the use of 'BIT' macroMylène Josserand2016-05-201-15/+15
| | | | | | | Replace bit shifts by BIT macro. Signed-off-by: Mylène Josserand <mylene.josserand@free-electrons.com> Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
* rtc: m41t80: replace i2c functions for smbus onesMylène Josserand2016-05-201-90/+44
| | | | | | | | | | | The driver used i2c_transfer methods to read and set date/time. The smbus methods should be used. This commit replaces i2c_transfer functions by i2c_smbus_XX_i2c_block_data for reading and setting the datetime. Signed-off-by: Mylène Josserand <mylene.josserand@free-electrons.com> Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
* rtc: m41t80: remove proc macroMylène Josserand2016-05-201-4/+0
| | | | | | | | Remove the CONFIG_RTC_INTF_PROC and CONFIG_RTC_INTF_PROC_MODULE macro which is not necessary anymore. Signed-off-by: Mylène Josserand <mylene.josserand@free-electrons.com> Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
* rtc: m41t80: update sysfs entries exportMylène Josserand2016-05-201-24/+32
| | | | | | | | | The driver used an old sysfs entry export. Update it to use the DEVICE_ATTR_XX macro and remove the unnecessary CONFIG_RTC_INTF_SYSFS macro. Signed-off-by: Mylène Josserand <mylene.josserand@free-electrons.com> Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
* rtc: m41t80: avoid out of range year valuesStefan Christ2016-03-191-0/+6
| | | | | | | | | | | | | Avoid saving an out of range year value to the RTC. Reading that value from the RTC again returns a totally wrong time value. For Example $ timedatectl set-ntp no $ timedatectl set-time "1990-01-01 12:12:00" # Reboot rtc-m41t80 0-0068: setting system clock to 2090-01-01 12:12:35 UTC (3786955955) Signed-off-by: Stefan Christ <s.christ@phytec.de> Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
* rtc: use more standard kernel logging stylesJoe Perches2015-04-171-2/+4
| | | | | | | | | | | | | | | | | | | | | | Neaten the logging a bit by adding #define pr_fmt Miscellanea: o Remove __FILE__/__func__ uses o Coalesce formats adding missing spaces o Align arguments o (rtc-cmos) Integrated 2 consecutive messages Signed-off-by: Joe Perches <joe@perches.com> Acked-by: Alexandre Belloni <alexandre.belloni@free-electrons.com> Cc: Alessandro Zummo <a.zummo@towertech.it> Cc: Joshua Kinard <kumba@gentoo.org> Cc: Chanwoo Choi <cw00.choi@samsung.com> Reviewed-by: Krzysztof Kozlowski <k.kozlowski@samsung.com> Tested-by: Krzysztof Kozlowski <k.kozlowski@samsung.com> Cc: Aaro Koskinen <aaro.koskinen@iki.fi> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* drivers/rtc/rtc-m41t80.c: add support for MicroCrystal rv4162Wolfram Sang2014-06-061-0/+1
| | | | | | | | Signed-off-by: Wolfram Sang <wsa@sang-engineering.com> Cc: Jingoo Han <jg1.han@samsung.com> 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>
* drivers/rtc/rtc-m41t80.c: propagate error value from smbus functionsWolfram Sang2014-06-061-14/+23
| | | | | | | | | | Don't replace the value we got from the I2C layer, just pass it on. Signed-off-by: Wolfram Sang <wsa@sang-engineering.com> Cc: Jingoo Han <jg1.han@samsung.com> 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>
* drivers/rtc/rtc-m41t80.c: clean up error pathsWolfram Sang2014-06-061-41/+23
| | | | | | | | | | | There is no cleanup needed when something fails in probe, so no need for goto. Directly return when something fails. Signed-off-by: Wolfram Sang <wsa@sang-engineering.com> 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>
* drivers/rtc/rtc-m41t80.c: remove DRV_VERSION macroWolfram Sang2014-06-061-6/+0
| | | | | | | | | | | History is in git, no need for sperate versioning. Also remove the success printout, RTC core does it, too. Signed-off-by: Wolfram Sang <wsa@sang-engineering.com> Cc: Jingoo Han <jg1.han@samsung.com> 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>
* drivers/rtc/rtc-m41t80.c: fix spacing related issueSachin Kamat2013-07-031-1/+1
| | | | | | | | | | | Silences the following checkpatch warning: WARNING: space prohibited before semicolon Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org> 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>
* rtc: rtc-m41t80: use devm_*() functionsJingoo Han2013-04-291-11/+5
| | | | | | | | Use devm_*() functions to make cleanup paths 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>
* drivers/rtc/rtc-m41t80.c: remove disabled alarm functionalityPaul Bolle2012-10-061-153/+4
| | | | | | | | | | | | | | | | | | | | | Commit c3b79770e51a ("rtc: m41t80: Workaround broken alarm functionality") disabled m41t80's alarm functions. But since those functions were not touched, building this driver triggers these GCC warnings: drivers/rtc/rtc-m41t80.c:216:12: warning: 'm41t80_rtc_alarm_irq_enable' defined but not used [-Wunused-function] drivers/rtc/rtc-m41t80.c:238:12: warning: 'm41t80_rtc_set_alarm' defined but not used [-Wunused-function] drivers/rtc/rtc-m41t80.c:308:12: warning: 'm41t80_rtc_read_alarm' defined but not used [-Wunused-function] Remove these functions (and the commented out references to them) to silence these warnings. Anyone wanting to fix the alarm irq functionality can easily find the removed code in the git log of this file or through some web searches. Signed-off-by: Paul Bolle <pebolle@tiscali.nl> Cc: John Stultz <john.stultz@linaro.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* rtc: convert rtc i2c drivers to module_i2c_driverAxel Lin2012-03-231-12/+1
| | | | | | | | | | | | | | | | | | | | | | | Factor out some boilerplate code for i2c driver registration into module_i2c_driver. Signed-off-by: Axel Lin <axel.lin@gmail.com> Cc: Piotr Ziecik <kosmo@semihalf.com> Cc: Alessandro Zummo <a.zummo@towertech.it> Cc: Scott Wood <scottwood@freescale.com> Cc: Srikanth Srinivasan <srikanth.srinivasan@freescale.com> Cc: Mike Rapoport <mike@compulab.co.il> Cc: Sergey Lapin <slapin@ossfans.org> Cc: Roman Fietze <roman.fietze@telemotive.de> Cc: Herbert Valerio Riedel <hvr@gnu.org> Cc: Alexander Bigga <ab@mycable.de> Cc: Dale Farnsworth <dale@farnsworth.org> Cc: Gregory Hermant <gregory.hermant@calao-systems.com> Cc: Wolfgang Grandegger <wg@grandegger.com> Cc: Martyn Welch <martyn.welch@ge.com> Cc: Byron Bradley <byron.bbradley@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* rtc: m41t80: Workaround broken alarm functionalityJohn Stultz2011-12-131-0/+9
| | | | | | | | | | | | | | | | | | | | | The m41t80 driver can read and set the alarm, but it doesn't seem to have a functional alarm irq. This causes failures when the generic core sees alarm functions, but then cannot use them properly for things like UIE mode. Disabling the alarm functions allows proper error reporting, and possible fallback to emulated modes. Once someone fixes the alarm irq functionality, this can be restored. CC: stable@kernel.org CC: Matt Turner <mattst88@gmail.com> CC: Nico Macrionitis <acrux@cruxppc.org> CC: Atsushi Nemoto <anemo@mba.ocn.ne.jp> Reported-by: Matt Turner <mattst88@gmail.com> Reported-by: Nico Macrionitis <acrux@cruxppc.org> Tested-by: Nico Macrionitis <acrux@cruxppc.org> Signed-off-by: John Stultz <john.stultz@linaro.org>
* rtc: m41t80: Initialize clientdata before registering deviceJohn Stultz2011-05-061-2/+3
| | | | | | | | | | | | | | | | | | | Commit f44f7f96a20 ("RTC: Initialize kernel state from RTC") uncovered an issue in a number of RTC drivers, where the drivers call rtc_device_register before initializing the clientdata. This frequently results in null pointer dereferences when the rtc_device_register immediately makes use of the rtc device, calling rtc_read_alarm. The solution is to ensure the clientdata is initialized prior to registering the rtc device. CC: Wolfram Sang <w.sang@pengutronix.de> CC: Alessandro Zummo <a.zummo@towertech.it> CC: Thomas Gleixner <tglx@linutronix.de> CC: rtc-linux@googlegroups.com Signed-off-by: John Stultz <john.stultz@linaro.org>
* RTC: Convert rtc drivers to use the alarm_irq_enable methodJohn Stultz2011-02-031-22/+8
| | | | | | | | | | | | | | | | | | | Some rtc drivers use the ioctl method instead of the alarm_irq_enable method for enabling alarm interupts. With the new virtualized RTC rework, its important for drivers to use the alarm_irq_enable instead. This patch converts the drivers that use the AIE ioctl method to use the alarm_irq_enable method. Other ioctl cmds are left untouched. I have not been able to test or even compile most of these drivers. Any help to make sure this change is correct would be appreciated! CC: Alessandro Zummo <a.zummo@towertech.it> CC: Thomas Gleixner <tglx@linutronix.de> CC: Marcelo Roberto Jimenez <mroberto@cpti.cetuc.puc-rio.br> Reported-by: Marcelo Roberto Jimenez <mroberto@cpti.cetuc.puc-rio.br> Tested-by: Marcelo Roberto Jimenez <mroberto@cpti.cetuc.puc-rio.br> Signed-off-by: John Stultz <john.stultz@linaro.org>
* Merge branch 'llseek' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/bklLinus Torvalds2010-10-221-0/+1
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * 'llseek' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/bkl: vfs: make no_llseek the default vfs: don't use BKL in default_llseek llseek: automatically add .llseek fop libfs: use generic_file_llseek for simple_attr mac80211: disallow seeks in minstrel debug code lirc: make chardev nonseekable viotape: use noop_llseek raw: use explicit llseek file operations ibmasmfs: use generic_file_llseek spufs: use llseek in all file operations arm/omap: use generic_file_llseek in iommu_debug lkdtm: use generic_file_llseek in debugfs net/wireless: use generic_file_llseek in debugfs drm: use noop_llseek
| * llseek: automatically add .llseek fopArnd Bergmann2010-10-151-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | All file_operations should get a .llseek operation so we can make nonseekable_open the default for future file operations without a .llseek pointer. The three cases that we can automatically detect are no_llseek, seq_lseek and default_llseek. For cases where we can we can automatically prove that the file offset is always ignored, we use noop_llseek, which maintains the current behavior of not returning an error from a seek. New drivers should normally not use noop_llseek but instead use no_llseek and call nonseekable_open at open time. Existing drivers can be converted to do the same when the maintainer knows for certain that no user code relies on calling seek on the device file. The generated code is often incorrectly indented and right now contains comments that clarify for each added line why a specific variant was chosen. In the version that gets submitted upstream, the comments will be gone and I will manually fix the indentation, because there does not seem to be a way to do that using coccinelle. Some amount of new code is currently sitting in linux-next that should get the same modifications, which I will do at the end of the merge window. Many thanks to Julia Lawall for helping me learn to write a semantic patch that does all this. ===== begin semantic patch ===== // This adds an llseek= method to all file operations, // as a preparation for making no_llseek the default. // // The rules are // - use no_llseek explicitly if we do nonseekable_open // - use seq_lseek for sequential files // - use default_llseek if we know we access f_pos // - use noop_llseek if we know we don't access f_pos, // but we still want to allow users to call lseek // @ open1 exists @ identifier nested_open; @@ nested_open(...) { <+... nonseekable_open(...) ...+> } @ open exists@ identifier open_f; identifier i, f; identifier open1.nested_open; @@ int open_f(struct inode *i, struct file *f) { <+... ( nonseekable_open(...) | nested_open(...) ) ...+> } @ read disable optional_qualifier exists @ identifier read_f; identifier f, p, s, off; type ssize_t, size_t, loff_t; expression E; identifier func; @@ ssize_t read_f(struct file *f, char *p, size_t s, loff_t *off) { <+... ( *off = E | *off += E | func(..., off, ...) | E = *off ) ...+> } @ read_no_fpos disable optional_qualifier exists @ identifier read_f; identifier f, p, s, off; type ssize_t, size_t, loff_t; @@ ssize_t read_f(struct file *f, char *p, size_t s, loff_t *off) { ... when != off } @ write @ identifier write_f; identifier f, p, s, off; type ssize_t, size_t, loff_t; expression E; identifier func; @@ ssize_t write_f(struct file *f, const char *p, size_t s, loff_t *off) { <+... ( *off = E | *off += E | func(..., off, ...) | E = *off ) ...+> } @ write_no_fpos @ identifier write_f; identifier f, p, s, off; type ssize_t, size_t, loff_t; @@ ssize_t write_f(struct file *f, const char *p, size_t s, loff_t *off) { ... when != off } @ fops0 @ identifier fops; @@ struct file_operations fops = { ... }; @ has_llseek depends on fops0 @ identifier fops0.fops; identifier llseek_f; @@ struct file_operations fops = { ... .llseek = llseek_f, ... }; @ has_read depends on fops0 @ identifier fops0.fops; identifier read_f; @@ struct file_operations fops = { ... .read = read_f, ... }; @ has_write depends on fops0 @ identifier fops0.fops; identifier write_f; @@ struct file_operations fops = { ... .write = write_f, ... }; @ has_open depends on fops0 @ identifier fops0.fops; identifier open_f; @@ struct file_operations fops = { ... .open = open_f, ... }; // use no_llseek if we call nonseekable_open //////////////////////////////////////////// @ nonseekable1 depends on !has_llseek && has_open @ identifier fops0.fops; identifier nso ~= "nonseekable_open"; @@ struct file_operations fops = { ... .open = nso, ... +.llseek = no_llseek, /* nonseekable */ }; @ nonseekable2 depends on !has_llseek @ identifier fops0.fops; identifier open.open_f; @@ struct file_operations fops = { ... .open = open_f, ... +.llseek = no_llseek, /* open uses nonseekable */ }; // use seq_lseek for sequential files ///////////////////////////////////// @ seq depends on !has_llseek @ identifier fops0.fops; identifier sr ~= "seq_read"; @@ struct file_operations fops = { ... .read = sr, ... +.llseek = seq_lseek, /* we have seq_read */ }; // use default_llseek if there is a readdir /////////////////////////////////////////// @ fops1 depends on !has_llseek && !nonseekable1 && !nonseekable2 && !seq @ identifier fops0.fops; identifier readdir_e; @@ // any other fop is used that changes pos struct file_operations fops = { ... .readdir = readdir_e, ... +.llseek = default_llseek, /* readdir is present */ }; // use default_llseek if at least one of read/write touches f_pos ///////////////////////////////////////////////////////////////// @ fops2 depends on !fops1 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @ identifier fops0.fops; identifier read.read_f; @@ // read fops use offset struct file_operations fops = { ... .read = read_f, ... +.llseek = default_llseek, /* read accesses f_pos */ }; @ fops3 depends on !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @ identifier fops0.fops; identifier write.write_f; @@ // write fops use offset struct file_operations fops = { ... .write = write_f, ... + .llseek = default_llseek, /* write accesses f_pos */ }; // Use noop_llseek if neither read nor write accesses f_pos /////////////////////////////////////////////////////////// @ fops4 depends on !fops1 && !fops2 && !fops3 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @ identifier fops0.fops; identifier read_no_fpos.read_f; identifier write_no_fpos.write_f; @@ // write fops use offset struct file_operations fops = { ... .write = write_f, .read = read_f, ... +.llseek = noop_llseek, /* read and write both use no f_pos */ }; @ depends on has_write && !has_read && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @ identifier fops0.fops; identifier write_no_fpos.write_f; @@ struct file_operations fops = { ... .write = write_f, ... +.llseek = noop_llseek, /* write uses no f_pos */ }; @ depends on has_read && !has_write && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @ identifier fops0.fops; identifier read_no_fpos.read_f; @@ struct file_operations fops = { ... .read = read_f, ... +.llseek = noop_llseek, /* read uses no f_pos */ }; @ depends on !has_read && !has_write && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @ identifier fops0.fops; @@ struct file_operations fops = { ... +.llseek = noop_llseek, /* no read or write fn */ }; ===== End semantic patch ===== Signed-off-by: Arnd Bergmann <arnd@arndb.de> Cc: Julia Lawall <julia@diku.dk> Cc: Christoph Hellwig <hch@infradead.org>
* | drivers: autoconvert trivial BKL users to private mutexArnd Bergmann2010-10-051-6/+7
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | All these files use the big kernel lock in a trivial way to serialize their private file operations, typically resulting from an earlier semi-automatic pushdown from VFS. None of these drivers appears to want to lock against other code, and they all use the BKL as the top-level lock in their file operations, meaning that there is no lock-order inversion problem. Consequently, we can remove the BKL completely, replacing it with a per-file mutex in every case. Using a scripted approach means we can avoid typos. These drivers do not seem to be under active maintainance from my brief investigation. Apologies to those maintainers that I have missed. file=$1 name=$2 if grep -q lock_kernel ${file} ; then if grep -q 'include.*linux.mutex.h' ${file} ; then sed -i '/include.*<linux\/smp_lock.h>/d' ${file} else sed -i 's/include.*<linux\/smp_lock.h>.*$/include <linux\/mutex.h>/g' ${file} fi sed -i ${file} \ -e "/^#include.*linux.mutex.h/,$ { 1,/^\(static\|int\|long\)/ { /^\(static\|int\|long\)/istatic DEFINE_MUTEX(${name}_mutex); } }" \ -e "s/\(un\)*lock_kernel\>[ ]*()/mutex_\1lock(\&${name}_mutex)/g" \ -e '/[ ]*cycle_kernel_lock();/d' else sed -i -e '/include.*\<smp_lock.h\>/d' ${file} \ -e '/cycle_kernel_lock()/d' fi Signed-off-by: Arnd Bergmann <arnd@arndb.de>
* rtc: m41t80: do not use rtc_valid_tm in m41t80_rtc_read_alarmAtsushi Nemoto2010-09-091-1/+1
| | | | | | | | | | | | | | | | Commit b485fe5ea ("rtc/m41t80: use rtc_valid_tm() to check returned tm") added rtc_valid_tm to m41t80_rtc_read_alarm() but it was wrong while the t->time does not contain complete date/time. This patch also fixes a warning: warning: passing argument 1 of 'rtc_valid_tm' from incompatible pointer type Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp> Cc: Wan ZongShun <mcuos.com@gmail.com> Cc: Alessandro Zummo <a.zummo@towertech.it> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* rtc/m41t80: use rtc_valid_tm() to check returned tmWan ZongShun2010-08-111-2/+2
| | | | | | | | | | Use rtc_valid_tm() to check returned struct rtc_time *tm - it can avoid returning wrong tm value. Signed-off-by: Wan ZongShun <mcuos.com@gmail.com> 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>
* rtc-m41t80: use nonseekable_open()Jan Blunck2010-05-271-5/+1
| | | | | | | | | | | Use nonseekable_open() for this since seeking is not supported anyway. Signed-off-by: Jan Blunck <jblunck@suse.de> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Paul Gortmaker <p_gortmaker@yahoo.com> 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>
* drivers: Push down BKL into various driversArnd Bergmann2010-05-171-2/+14
| | | | | | | | | | | | These are the last remaining device drivers using the ->ioctl file operation in the drivers directory (except from v4l drivers). [fweisbec: drop i8k pushdown as it has been done from procfs pushdown branch already] Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
* rtc: add m41t62 support to rtc-m41t80 driverDaniel Glockner2009-04-021-5/+13
| | | | | | | | | | | | Compared to the other supported chips, the m41t62 uses a different register to set the square wave frequency. Signed-off-by: Daniel Glockner <dg@emlix.com> Cc: Chris Zankel <chris@zankel.net> Cc: David Brownell <david-b@pacbell.net> 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>
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-06 23:04:57 +0000