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path: root/drivers/rtc/rtc-ac100.c
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2018-02-02Merge tag 'rtc-4.16' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/abelloni/linux Pull RTC updates from Alexandre Belloni: "Not much this cycle. I've pushed the at32ap700x removal late but it is unlikely to cause any issues. Summary: Subsystem: - Move ABI documentation to Documentation/ABI New driver: - NXP i.MX53 SRTC - Chrome OS EC RTC Drivers: - Remove at32ap700x - Many fixes in various error paths" * tag 'rtc-4.16' of git://git.kernel.org/pub/scm/linux/kernel/git/abelloni/linux: rtc: remove rtc-at32ap700x Documentation: rtc: move iotcl interface documentation to ABI Documentation: rtc: add sysfs file permissions Documentation: rtc: move sysfs documentation to ABI rtc: mxc_v2: remove __exit annotation rtc: mxc_v2: Remove unnecessary platform_get_resource() error check rtc: add mxc driver for i.MX53 SRTC dt-bindings: rtc: add bindings for i.MX53 SRTC rtc: r7301: Fix a possible sleep-in-atomic bug in rtc7301_set_time rtc: r7301: Fix a possible sleep-in-atomic bug in rtc7301_read_time rtc: omap: fix unbalanced clk_prepare_enable/clk_disable_unprepare rtc: ac100: Fix multiple race conditions rtc: sun6i: ensure rtc is kfree'd on error rtc: cros-ec: add cros-ec-rtc driver. mfd: cros_ec: Introduce RTC commands and events definitions. rtc: stm32: Fix copyright rtc: Remove unused RTC_DEVICE_NAME_SIZE rtc: r9701: Remove r9701_remove function rtc: brcmstb-waketimer: fix error handling in brcmstb_waketmr_probe()
2017-12-28clk: divider: fix incorrect usage of container_ofJerome Brunet
divider_recalc_rate() is an helper function used by clock divider of different types, so the structure containing the 'hw' pointer is not always a 'struct clk_divider' At the following line: > div = _get_div(table, val, flags, divider->width); in several cases, the value of 'divider->width' is garbage as the actual structure behind this memory is not a 'struct clk_divider' Fortunately, this width value is used by _get_val() only when CLK_DIVIDER_MAX_AT_ZERO flag is set. This has never been the case so far when the structure is not a 'struct clk_divider'. This is probably why we did not notice this bug before Fixes: afe76c8fd030 ("clk: allow a clk divider with max divisor when zero") Signed-off-by: Jerome Brunet <jbrunet@baylibre.com> Acked-by: Alexandre Belloni <alexandre.belloni@free-electrons.com> Acked-by: Sylvain Lemieux <slemieux.tyco@gmail.com> Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2017-12-18rtc: ac100: Fix multiple race conditionsAlexandre Belloni
The probe function is not allowed to fail after registering the RTC 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* */ Also, the interrupt handler: ac100_rtc_irq() is dereferencing chip->rtc but this may still be NULL when it is called, resulting in: Unable to handle kernel NULL pointer dereference at virtual address 00000194 pgd = (ptrval) [00000194] *pgd=00000000 Internal error: Oops: 5 [#1] SMP ARM Modules linked in: CPU: 0 PID: 72 Comm: irq/71-ac100-rt Not tainted 4.15.0-rc1-next-20171201-dirty #120 Hardware name: Allwinner sun8i Family task: (ptrval) task.stack: (ptrval) PC is at mutex_lock+0x14/0x3c LR is at ac100_rtc_irq+0x38/0xc8 pc : [<c06543a4>] lr : [<c04d9a2c>] psr: 60000053 sp : ee9c9f28 ip : 00000000 fp : ee9adfdc r10: 00000000 r9 : c0a04c48 r8 : c015ed18 r7 : ee9bd600 r6 : ee9c9f28 r5 : ee9af590 r4 : c0a04c48 r3 : ef3cb3c0 r2 : 00000000 r1 : ee9af590 r0 : 00000194 Flags: nZCv IRQs on FIQs off Mode SVC_32 ISA ARM Segment none Control: 10c5387d Table: 4000406a DAC: 00000051 Process irq/71-ac100-rt (pid: 72, stack limit = 0x(ptrval)) Stack: (0xee9c9f28 to 0xee9ca000) 9f20: 00000000 7c2fd1be c015ed18 ee9adf40 ee9c0400 ee9c0400 9f40: ee9adf40 c015ed34 ee9c8000 ee9adf64 ee9c0400 c015f040 ee9adf80 00000000 9f60: c015ee24 7c2fd1be ee9adfc0 ee9adf80 00000000 ee9c8000 ee9adf40 c015eef4 9f80: ef1eba34 c0138f14 ee9c8000 ee9adf80 c0138df4 00000000 00000000 00000000 9fa0: 00000000 00000000 00000000 c01010e8 00000000 00000000 00000000 00000000 9fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 9fe0: 00000000 00000000 00000000 00000000 00000013 00000000 ffffffff ffffffff [<c06543a4>] (mutex_lock) from [<c04d9a2c>] (ac100_rtc_irq+0x38/0xc8) [<c04d9a2c>] (ac100_rtc_irq) from [<c015ed34>] (irq_thread_fn+0x1c/0x54) [<c015ed34>] (irq_thread_fn) from [<c015f040>] (irq_thread+0x14c/0x214) [<c015f040>] (irq_thread) from [<c0138f14>] (kthread+0x120/0x150) [<c0138f14>] (kthread) from [<c01010e8>] (ret_from_fork+0x14/0x2c) Solve both issues by moving to devm_rtc_allocate_device()/rtc_register_device() Reported-by: Quentin Schulz <quentin.schulz@free-electrons.com> Tested-by: Quentin Schulz <quentin.schulz@free-electrons.com> Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2016-09-22rtc: ac100: Add NULL checking for devm_kzalloc callAxel Lin
devm_kzalloc can return NULL, add NULL checking to prevent NULL pointer dereference. Signed-off-by: Axel Lin <axel.lin@ingics.com> Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2016-08-31rtc: ac100: support clock-output-names in device tree bindingChen-Yu Tsai
The ac100 device tree binding specifies the usage of clock-output-names to specify the names of its 3 clock outputs. This is needed for orphan clock resolution, when the ac100 is probed much later than any clocks that consume any of its outputs. This wasn't supported by the driver. Add support for this. Signed-off-by: Chen-Yu Tsai <wens@csie.org> Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2016-08-08rtc: ac100: Add clk output supportChen-Yu Tsai
The AC100's RTC side has 3 clock outputs on external pins, which can provide a clock signal to the SoC or other modules, such as WiFi or GSM modules. Support this with a custom clk driver integrated with the rtc driver. Signed-off-by: Chen-Yu Tsai <wens@csie.org> Acked-by: Alexandre Belloni <alexandre.belloni@free-electrons.com> Signed-off-by: Lee Jones <lee.jones@linaro.org>
2016-08-08rtc: ac100: Add RTC driver for X-Powers AC100Chen-Yu Tsai
X-Powers AC100 is a codec / RTC combo chip. This driver supports the RTC sub-device. The RTC block also has clock outputs and non-volatile storage. Non-volatile storage wthin the RTC hardware is not supported. Clock output support is added in the next patch. Signed-off-by: Chen-Yu Tsai <wens@csie.org> Acked-by: Alexandre Belloni <alexandre.belloni@free-electrons.com> Signed-off-by: Lee Jones <lee.jones@linaro.org>