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2013-03-26regmap: core: Make raw write available to regcacheMark Brown
This allows the cache to sync values directly to the device when stored in native format and also allows asynchronous I/O. Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2013-03-26regmap: core: Warn on invalid operation combinationsMark Brown
Don't grind to a screaming halt, just generate a warning. Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2013-03-21regmap: don't corrupt work buffer in _regmap_raw_write()Stephen Warren
_regmap_raw_write() contains code to call regcache_write() to write values to the cache. That code calls memcpy() to copy the value data to the start of the work_buf. However, at least when _regmap_raw_write() is called from _regmap_bus_raw_write(), the value data is in the work_buf, and this memcpy() operation may over-write part of that value data, depending on the value of reg_bytes + pad_bytes. At least when using reg_bytes==1 and pad_bytes==0, corruption of the value data does occur. To solve this, remove the memcpy() operation, and modify the subsequent .parse_val() call to parse the original value buffer directly. At least in the case of 8-bit register address and 16-bit values, and writes of single registers at a time, this memcpy-then-parse combination used to cancel each-other out; for a work-buffer containing xx 89 03, the memcpy changed it to 89 03 03, and the parse_val changed it back to 89 89 03, thus leaving the value uncorrupted. This appears completely accidental though. Since commit 8a819ff "regmap: core: Split out in place value parsing", .parse_val only returns the parsed value, and does not modify the buffer, and hence does not (accidentally) undo the corruption caused by memcpy(). This caused bogus values to get written to HW, thus preventing e.g. audio playback on systems with a WM8903 CODEC. This patch fixes that. Signed-off-by: Stephen Warren <swarren@nvidia.com> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2013-03-19regmap: irq: Clarify error message when we fail to request primary IRQMark Brown
Display the name for the chip rather than just the primary IRQ so it is clearer what exactly has failed. Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2013-03-17Merge tag 'v3.9-rc3' into nextDmitry Torokhov
Merge with mainline to bring in module_platform_driver_probe() and devm_ioremap_resource().
2013-03-15base: core: WARN() about bogus permissions on device attributesFelipe Balbi
Whenever a struct device_attribute is registered with mismatched permissions - read permission without a show routine or write permission without store routine - we will issue a big warning so we catch those early enough. Signed-off-by: Felipe Balbi <balbi@ti.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-03-13regmap: cache Fix regcache-rbtree syncLars-Peter Clausen
The last register block, which falls into the specified range, is not handled correctly. The formula which calculates the number of register which should be synced is inverse (and off by one). E.g. if all registers in that block should be synced only one is synced, and if only one should be synced all (but one) are synced. To calculate the number of registers that need to be synced we need to subtract the number of the first register in the block from the max register number and add one. This patch updates the code accordingly. The issue was introduced in commit ac8d91c ("regmap: Supply ranges to the sync operations"). Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Cc: stable@vger.kernel.org
2013-03-13device: separate all subsys mutexesMichal Hocko
ca22e56d (driver-core: implement 'sysdev' functionality for regular devices and buses) has introduced bus_register macro with a static key to distinguish different subsys mutex classes. This however doesn't work for different subsys which use a common registering function. One example is subsys_system_register (and mce_device and cpu_device). In the end this leads to the following lockdep splat: [ 207.271924] ====================================================== [ 207.271932] [ INFO: possible circular locking dependency detected ] [ 207.271942] 3.9.0-rc1-0.7-default+ #34 Not tainted [ 207.271948] ------------------------------------------------------- [ 207.271957] bash/10493 is trying to acquire lock: [ 207.271963] (subsys mutex){+.+.+.}, at: [<ffffffff8134af27>] bus_remove_device+0x37/0x1c0 [ 207.271987] [ 207.271987] but task is already holding lock: [ 207.271995] (cpu_hotplug.lock){+.+.+.}, at: [<ffffffff81046ccf>] cpu_hotplug_begin+0x2f/0x60 [ 207.272012] [ 207.272012] which lock already depends on the new lock. [ 207.272012] [ 207.272023] [ 207.272023] the existing dependency chain (in reverse order) is: [ 207.272033] [ 207.272033] -> #4 (cpu_hotplug.lock){+.+.+.}: [ 207.272044] [<ffffffff810ae329>] lock_acquire+0xe9/0x120 [ 207.272056] [<ffffffff814ad807>] mutex_lock_nested+0x37/0x360 [ 207.272069] [<ffffffff81046ba9>] get_online_cpus+0x29/0x40 [ 207.272082] [<ffffffff81185210>] drain_all_stock+0x30/0x150 [ 207.272094] [<ffffffff811853da>] mem_cgroup_reclaim+0xaa/0xe0 [ 207.272104] [<ffffffff8118775e>] __mem_cgroup_try_charge+0x51e/0xcf0 [ 207.272114] [<ffffffff81188486>] mem_cgroup_charge_common+0x36/0x60 [ 207.272125] [<ffffffff811884da>] mem_cgroup_newpage_charge+0x2a/0x30 [ 207.272135] [<ffffffff81150531>] do_wp_page+0x231/0x830 [ 207.272147] [<ffffffff8115151e>] handle_pte_fault+0x19e/0x8d0 [ 207.272157] [<ffffffff81151da8>] handle_mm_fault+0x158/0x1e0 [ 207.272166] [<ffffffff814b6153>] do_page_fault+0x2a3/0x4e0 [ 207.272178] [<ffffffff814b2578>] page_fault+0x28/0x30 [ 207.272189] [ 207.272189] -> #3 (&mm->mmap_sem){++++++}: [ 207.272199] [<ffffffff810ae329>] lock_acquire+0xe9/0x120 [ 207.272208] [<ffffffff8114c5ad>] might_fault+0x6d/0x90 [ 207.272218] [<ffffffff811a11e3>] filldir64+0xb3/0x120 [ 207.272229] [<ffffffffa013fc19>] call_filldir+0x89/0x130 [ext3] [ 207.272248] [<ffffffffa0140377>] ext3_readdir+0x6b7/0x7e0 [ext3] [ 207.272263] [<ffffffff811a1519>] vfs_readdir+0xa9/0xc0 [ 207.272273] [<ffffffff811a15cb>] sys_getdents64+0x9b/0x110 [ 207.272284] [<ffffffff814bb599>] system_call_fastpath+0x16/0x1b [ 207.272296] [ 207.272296] -> #2 (&type->i_mutex_dir_key#3){+.+.+.}: [ 207.272309] [<ffffffff810ae329>] lock_acquire+0xe9/0x120 [ 207.272319] [<ffffffff814ad807>] mutex_lock_nested+0x37/0x360 [ 207.272329] [<ffffffff8119c254>] link_path_walk+0x6f4/0x9a0 [ 207.272339] [<ffffffff8119e7fa>] path_openat+0xba/0x470 [ 207.272349] [<ffffffff8119ecf8>] do_filp_open+0x48/0xa0 [ 207.272358] [<ffffffff8118d81c>] file_open_name+0xdc/0x110 [ 207.272369] [<ffffffff8118d885>] filp_open+0x35/0x40 [ 207.272378] [<ffffffff8135c76e>] _request_firmware+0x52e/0xb20 [ 207.272389] [<ffffffff8135cdd6>] request_firmware+0x16/0x20 [ 207.272399] [<ffffffffa03bdb91>] request_microcode_fw+0x61/0xd0 [microcode] [ 207.272416] [<ffffffffa03bd554>] microcode_init_cpu+0x104/0x150 [microcode] [ 207.272431] [<ffffffffa03bd61c>] mc_device_add+0x7c/0xb0 [microcode] [ 207.272444] [<ffffffff8134a419>] subsys_interface_register+0xc9/0x100 [ 207.272457] [<ffffffffa04fc0f4>] 0xffffffffa04fc0f4 [ 207.272472] [<ffffffff81000202>] do_one_initcall+0x42/0x180 [ 207.272485] [<ffffffff810bbeff>] load_module+0x19df/0x1b70 [ 207.272499] [<ffffffff810bc376>] sys_init_module+0xe6/0x130 [ 207.272511] [<ffffffff814bb599>] system_call_fastpath+0x16/0x1b [ 207.272523] [ 207.272523] -> #1 (umhelper_sem){++++.+}: [ 207.272537] [<ffffffff810ae329>] lock_acquire+0xe9/0x120 [ 207.272548] [<ffffffff814ae9c4>] down_read+0x34/0x50 [ 207.272559] [<ffffffff81062bff>] usermodehelper_read_trylock+0x4f/0x100 [ 207.272575] [<ffffffff8135c7dd>] _request_firmware+0x59d/0xb20 [ 207.272587] [<ffffffff8135cdd6>] request_firmware+0x16/0x20 [ 207.272599] [<ffffffffa03bdb91>] request_microcode_fw+0x61/0xd0 [microcode] [ 207.272613] [<ffffffffa03bd554>] microcode_init_cpu+0x104/0x150 [microcode] [ 207.272627] [<ffffffffa03bd61c>] mc_device_add+0x7c/0xb0 [microcode] [ 207.272641] [<ffffffff8134a419>] subsys_interface_register+0xc9/0x100 [ 207.272654] [<ffffffffa04fc0f4>] 0xffffffffa04fc0f4 [ 207.272666] [<ffffffff81000202>] do_one_initcall+0x42/0x180 [ 207.272678] [<ffffffff810bbeff>] load_module+0x19df/0x1b70 [ 207.272690] [<ffffffff810bc376>] sys_init_module+0xe6/0x130 [ 207.272702] [<ffffffff814bb599>] system_call_fastpath+0x16/0x1b [ 207.272715] [ 207.272715] -> #0 (subsys mutex){+.+.+.}: [ 207.272729] [<ffffffff810ae002>] __lock_acquire+0x13b2/0x15f0 [ 207.272740] [<ffffffff810ae329>] lock_acquire+0xe9/0x120 [ 207.272751] [<ffffffff814ad807>] mutex_lock_nested+0x37/0x360 [ 207.272763] [<ffffffff8134af27>] bus_remove_device+0x37/0x1c0 [ 207.272775] [<ffffffff81349114>] device_del+0x134/0x1f0 [ 207.272786] [<ffffffff813491f2>] device_unregister+0x22/0x60 [ 207.272798] [<ffffffff814a24ea>] mce_cpu_callback+0x15e/0x1ad [ 207.272812] [<ffffffff814b6402>] notifier_call_chain+0x72/0x130 [ 207.272824] [<ffffffff81073d6e>] __raw_notifier_call_chain+0xe/0x10 [ 207.272839] [<ffffffff81498f76>] _cpu_down+0x1d6/0x350 [ 207.272851] [<ffffffff81499130>] cpu_down+0x40/0x60 [ 207.272862] [<ffffffff8149cc55>] store_online+0x75/0xe0 [ 207.272874] [<ffffffff813474a0>] dev_attr_store+0x20/0x30 [ 207.272886] [<ffffffff812090d9>] sysfs_write_file+0xd9/0x150 [ 207.272900] [<ffffffff8118e10b>] vfs_write+0xcb/0x130 [ 207.272911] [<ffffffff8118e924>] sys_write+0x64/0xa0 [ 207.272923] [<ffffffff814bb599>] system_call_fastpath+0x16/0x1b [ 207.272936] [ 207.272936] other info that might help us debug this: [ 207.272936] [ 207.272952] Chain exists of: [ 207.272952] subsys mutex --> &mm->mmap_sem --> cpu_hotplug.lock [ 207.272952] [ 207.272973] Possible unsafe locking scenario: [ 207.272973] [ 207.272984] CPU0 CPU1 [ 207.272992] ---- ---- [ 207.273000] lock(cpu_hotplug.lock); [ 207.273009] lock(&mm->mmap_sem); [ 207.273020] lock(cpu_hotplug.lock); [ 207.273031] lock(subsys mutex); [ 207.273040] [ 207.273040] *** DEADLOCK *** [ 207.273040] [ 207.273055] 5 locks held by bash/10493: [ 207.273062] #0: (&buffer->mutex){+.+.+.}, at: [<ffffffff81209049>] sysfs_write_file+0x49/0x150 [ 207.273080] #1: (s_active#150){.+.+.+}, at: [<ffffffff812090c2>] sysfs_write_file+0xc2/0x150 [ 207.273099] #2: (x86_cpu_hotplug_driver_mutex){+.+.+.}, at: [<ffffffff81027557>] cpu_hotplug_driver_lock+0x17/0x20 [ 207.273121] #3: (cpu_add_remove_lock){+.+.+.}, at: [<ffffffff8149911c>] cpu_down+0x2c/0x60 [ 207.273140] #4: (cpu_hotplug.lock){+.+.+.}, at: [<ffffffff81046ccf>] cpu_hotplug_begin+0x2f/0x60 [ 207.273158] [ 207.273158] stack backtrace: [ 207.273170] Pid: 10493, comm: bash Not tainted 3.9.0-rc1-0.7-default+ #34 [ 207.273180] Call Trace: [ 207.273192] [<ffffffff810ab373>] print_circular_bug+0x223/0x310 [ 207.273204] [<ffffffff810ae002>] __lock_acquire+0x13b2/0x15f0 [ 207.273216] [<ffffffff812086b0>] ? sysfs_hash_and_remove+0x60/0xc0 [ 207.273227] [<ffffffff810ae329>] lock_acquire+0xe9/0x120 [ 207.273239] [<ffffffff8134af27>] ? bus_remove_device+0x37/0x1c0 [ 207.273251] [<ffffffff814ad807>] mutex_lock_nested+0x37/0x360 [ 207.273263] [<ffffffff8134af27>] ? bus_remove_device+0x37/0x1c0 [ 207.273274] [<ffffffff812086b0>] ? sysfs_hash_and_remove+0x60/0xc0 [ 207.273286] [<ffffffff8134af27>] bus_remove_device+0x37/0x1c0 [ 207.273298] [<ffffffff81349114>] device_del+0x134/0x1f0 [ 207.273309] [<ffffffff813491f2>] device_unregister+0x22/0x60 [ 207.273321] [<ffffffff814a24ea>] mce_cpu_callback+0x15e/0x1ad [ 207.273332] [<ffffffff814b6402>] notifier_call_chain+0x72/0x130 [ 207.273344] [<ffffffff81073d6e>] __raw_notifier_call_chain+0xe/0x10 [ 207.273356] [<ffffffff81498f76>] _cpu_down+0x1d6/0x350 [ 207.273368] [<ffffffff81027557>] ? cpu_hotplug_driver_lock+0x17/0x20 [ 207.273380] [<ffffffff81499130>] cpu_down+0x40/0x60 [ 207.273391] [<ffffffff8149cc55>] store_online+0x75/0xe0 [ 207.273402] [<ffffffff813474a0>] dev_attr_store+0x20/0x30 [ 207.273413] [<ffffffff812090d9>] sysfs_write_file+0xd9/0x150 [ 207.273425] [<ffffffff8118e10b>] vfs_write+0xcb/0x130 [ 207.273436] [<ffffffff8118e924>] sys_write+0x64/0xa0 [ 207.273447] [<ffffffff814bb599>] system_call_fastpath+0x16/0x1b Which reports a false possitive deadlock because it sees: 1) load_module -> subsys_interface_register -> mc_deveice_add (*) -> subsys->p->mutex -> link_path_walk -> lookup_slow -> i_mutex 2) sys_write -> _cpu_down -> cpu_hotplug_begin -> cpu_hotplug.lock -> mce_cpu_callback -> mce_device_remove(**) -> device_unregister -> bus_remove_device -> subsys mutex 3) vfs_readdir -> i_mutex -> filldir64 -> might_fault -> might_lock_read(mmap_sem) -> page_fault -> mmap_sem -> drain_all_stock -> cpu_hotplug.lock but 1) takes cpu_subsys subsys (*) but 2) takes mce_device subsys (**) so the deadlock is not possible AFAICS. The fix is quite simple. We can pull the key inside bus_type structure because they are defined per device so the pointer will be unique as well. bus_register doesn't need to be a macro anymore so change it to the inline. We could get rid of __bus_register as there is no other caller but maybe somebody will want to use a different key so keep it around for now. Reported-by: Li Zefan <lizefan@huawei.com> Signed-off-by: Michal Hocko <mhocko@suse.cz> Signed-off-by: Jiri Kosina <jkosina@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-03-13regmap: rbtree Expose total memory consumption in the rbtree debugfs entryDimitris Papastamos
Provide a feel of how much overhead the rbtree cache adds to the game. [Slightly reworded output in debugfs -- broonie] Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2013-03-12driver/base: implement subsys_virtual_register()Tejun Heo
Kay tells me the most appropriate place to expose workqueues to userland would be /sys/devices/virtual/workqueues/WQ_NAME which is symlinked to /sys/bus/workqueue/devices/WQ_NAME and that we're lacking a way to do that outside of driver core as virtual_device_parent() isn't exported and there's no inteface to conveniently create a virtual subsystem. This patch implements subsys_virtual_register() by factoring out subsys_register() from subsys_system_register() and using it with virtual_device_parent() as the origin directory. It's identical to subsys_system_register() other than the origin directory but we aren't gonna restrict the device names which should be used under it. This will be used to expose workqueue attributes to userland. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Kay Sievers <kay.sievers@vrfy.org>
2013-03-12regmap: Initialize `map->debugfs' before regcacheDimitris Papastamos
In the rbtree code we are exposing statistics relating to the number of nodes/registers of the rbtree cache for each of the devices. Ensure that `map->debugfs' has been initialized before we attempt to initialize the debugfs entry for the rbtree cache. Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Cc: stable@vger.kernel.org
2013-03-07Merge tag 'pm+acpi-3.9-rc2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull ACPI and power management fixes from Rafael J Wysocki: - Two fixes for the new intel_pstate driver from Dirk Brandewie. - Fix for incorrect usage of the .find_bridge() callback from struct acpi_bus_type in the USB core and subsequent removal of that callback from Rafael J Wysocki. - ACPI processor driver cleanups from Chen Gang and Syam Sidhardhan. - ACPI initialization and error messages fix from Joe Perches. - Operating Performance Points documentation improvement from Nishanth Menon. - Fixes for memory leaks and potential concurrency issues and sysfs attributes leaks during device removal in the core device PM QoS code from Rafael J Wysocki. - Calxeda Highbank cpufreq driver simplification from Emilio López. - cpufreq comment cleanup from Namhyung Kim. - Fix for a section mismatch in Calxeda Highbank interprocessor communication code from Mark Langsdorf (this is not a PM fix strictly speaking, but the code in question went in through the PM tree). * tag 'pm+acpi-3.9-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: cpufreq / intel_pstate: Do not load on VM that does not report max P state. cpufreq / intel_pstate: Fix intel_pstate_init() error path ACPI / glue: Drop .find_bridge() callback from struct acpi_bus_type ACPI / glue: Add .match() callback to struct acpi_bus_type ACPI / porocessor: Beautify code, pr->id is u32 which is never < 0 ACPI / processor: Remove redundant NULL check before kfree ACPI / Sleep: Avoid interleaved message on errors PM / QoS: Remove device PM QoS sysfs attributes at the right place PM / QoS: Fix concurrency issues and memory leaks in device PM QoS cpufreq: highbank: do not initialize array with a loop PM / OPP: improve introductory documentation cpufreq: Fix a typo in comment mailbox, pl320-ipc: remove __init from probe function
2013-03-07Merge tag 'regmap-v3.9-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regmap Pull regmap PM fix from Mark Brown: "A simple fix to stop us leaking a runtime PM reference in the case where we fail to enable a device." * tag 'regmap-v3.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regmap: regmap: irq: call pm_runtime_put in pm_runtime_get_sync failed case
2013-03-04PM / QoS: Remove device PM QoS sysfs attributes at the right placeRafael J. Wysocki
Device PM QoS sysfs attributes, if present during device removal, are removed from within device_pm_remove(), which is too late, since dpm_sysfs_remove() has already removed the whole attribute group they belonged to. However, moving the removal of those attributes to dpm_sysfs_remove() alone is not sufficient, because in theory they still can be re-added right after being removed by it (the device's driver is still bound to it at that point). For this reason, move the entire desctruction of device PM QoS constraints to dpm_sysfs_remove() and make it prevent any new constraints from being added after it has run. Also, move the initialization of the power.qos field in struct device to device_pm_init_common() and drop the no longer needed dev_pm_qos_constraints_init(). Reported-by: Sasha Levin <sasha.levin@oracle.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-03-04PM / QoS: Fix concurrency issues and memory leaks in device PM QoSRafael J. Wysocki
The current device PM QoS code assumes that certain functions will never be called in parallel with each other (for example, it is assumed that dev_pm_qos_expose_flags() won't be called in parallel with dev_pm_qos_hide_flags() for the same device and analogously for the latency limit), which may be overly optimistic. Moreover, dev_pm_qos_expose_flags() and dev_pm_qos_expose_latency_limit() leak memory in error code paths (req needs to be freed on errors) and __dev_pm_qos_drop_user_request() forgets to free the request. To fix the above issues put more things under the device PM QoS mutex to make them mutually exclusive and add the missing freeing of memory. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-03-04regmap: debugfs: Add a registers `range' fileDimitris Papastamos
This file lists the register ranges in the register map. The condition to split the range is based on whether the block is readable or not. Ensure that we lock the `debugfs_off_cache' list whenever we access and modify the list. There is a possible race otherwise between the read() operations of the `registers' file and the `range' file. Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2013-03-04regmap: debugfs: Simplify calculation of `c->max_reg'Dimitris Papastamos
We don't need to use any of the file position information to calculate the base and max register of each block. Just use the counter directly. Set `i = base' at the top to avoid GCC flow analysis bugs. The value of `i' can never be undefined or 0 in the if (c) { ... }. Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2013-03-04regmap: cache: Store caches in native register format where possibleMark Brown
This allows the cached data to be sent directly to the device when we sync it. Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2013-03-04regmap: core: Split out in place value parsingMark Brown
Currently the value parsing operations both return the parsed value and modify the passed buffer. This precludes their use in places like the cache code so split out the in place modification into a new parse_inplace() operation. Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2013-03-04regmap: cache: Use regcache_get_value() to check if we updatedMark Brown
Factor things out a little. Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2013-03-04regmap: cache: Pass the map rather than the word size when updating valuesMark Brown
It's more idiomatic to pass the map structure around and this means we can use other bits of information from the map. Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2013-03-04regmap: rbtree: Don't bother checking for noop updatesMark Brown
If we're updating a value in place it's more work to read the value and compare the value with what we're about to set than it is to just write the value into the cache; there are no further operations after writing in the code even though there's an early return here. Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2013-03-04regmap: async: Add tracepoints for async I/OMark Brown
Trace when we start and complete async writes, and when we start and finish blocking for their completion. This is useful for performance analysis of the resulting I/O patterns. Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2013-03-01regmap: irq: call pm_runtime_put in pm_runtime_get_sync failed caseLi Fei
Even in failed case of pm_runtime_get_sync, the usage_count is incremented. In order to keep the usage_count with correct value and runtime power management to behave correctly, call pm_runtime_put(_sync) in such case. Signed-off-by Liu Chuansheng <chuansheng.liu@intel.com> Signed-off-by: Li Fei <fei.li@intel.com> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2013-02-27CHROMIUM: dma-buf: restore args on failure of dma_buf_mmapJohn Sheu
Callers to dma_buf_mmap expect to fput() the vma struct's vm_file themselves on failure. Not restoring the struct's data on failure causes a double-decrement of the vm_file's refcount. Signed-off-by: John Sheu <sheu@google.com> Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch> Signed-off-by: Sumit Semwal <sumit.semwal@linaro.org>
2013-02-27dma-buf: implement vmap refcounting in the interface logicDaniel Vetter
All drivers which implement this need to have some sort of refcount to allow concurrent vmap usage. Hence implement this in the dma-buf core. To protect against concurrent calls we need a lock, which potentially causes new funny locking inversions. But this shouldn't be a problem for exporters with statically allocated backing storage, and more dynamic drivers have decent issues already anyway. Inspired by some refactoring patches from Aaron Plattner, who implemented the same idea, but only for drm/prime drivers. v2: Check in dma_buf_release that no dangling vmaps are left. Suggested by Aaron Plattner. We might want to do similar checks for attachments, but that's for another patch. Also fix up ERR_PTR return for vmap. v3: Check whether the passed-in vmap address matches with the cached one for vunmap. Eventually we might want to remove that parameter - compared to the kmap functions there's no need for the vaddr for unmapping. Suggested by Chris Wilson. v4: Fix a brown-paper-bag bug spotted by Aaron Plattner. Cc: Aaron Plattner <aplattner@nvidia.com> Reviewed-by: Aaron Plattner <aplattner@nvidia.com> Tested-by: Aaron Plattner <aplattner@nvidia.com> Reviewed-by: Rob Clark <rob@ti.com> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch> Signed-off-by: Sumit Semwal <sumit.semwal@linaro.org>
2013-02-26Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull vfs pile (part one) from Al Viro: "Assorted stuff - cleaning namei.c up a bit, fixing ->d_name/->d_parent locking violations, etc. The most visible changes here are death of FS_REVAL_DOT (replaced with "has ->d_weak_revalidate()") and a new helper getting from struct file to inode. Some bits of preparation to xattr method interface changes. Misc patches by various people sent this cycle *and* ocfs2 fixes from several cycles ago that should've been upstream right then. PS: the next vfs pile will be xattr stuff." * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (46 commits) saner proc_get_inode() calling conventions proc: avoid extra pde_put() in proc_fill_super() fs: change return values from -EACCES to -EPERM fs/exec.c: make bprm_mm_init() static ocfs2/dlm: use GFP_ATOMIC inside a spin_lock ocfs2: fix possible use-after-free with AIO ocfs2: Fix oops in ocfs2_fast_symlink_readpage() code path get_empty_filp()/alloc_file() leave both ->f_pos and ->f_version zero target: writev() on single-element vector is pointless export kernel_write(), convert open-coded instances fs: encode_fh: return FILEID_INVALID if invalid fid_type kill f_vfsmnt vfs: kill FS_REVAL_DOT by adding a d_weak_revalidate dentry op nfsd: handle vfs_getattr errors in acl protocol switch vfs_getattr() to struct path default SET_PERSONALITY() in linux/elf.h ceph: prepopulate inodes only when request is aborted d_hash_and_lookup(): export, switch open-coded instances 9p: switch v9fs_set_create_acl() to inode+fid, do it before d_instantiate() 9p: split dropping the acls from v9fs_set_create_acl() ...
2013-02-26switch vfs_getattr() to struct pathAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-02-25devres: allow adding custom actions to the stackDmitry Torokhov
Sometimes drivers need to execute one-off actions in their error handling or device teardown paths. An example would be toggling a GPIO line to reset the controlled device into predefined state. To allow performing such actions when using managed resources let's allow adding them to stack/group of devres resources. Acked-by: Tejun Heo <tj@kernel.org> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
2013-02-25Merge tag 'modules-next-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux Pull module update from Rusty Russell: "The sweeping change is to make add_taint() explicitly indicate whether to disable lockdep, but it's a mechanical change." * tag 'modules-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux: MODSIGN: Add option to not sign modules during modules_install MODSIGN: Add -s <signature> option to sign-file MODSIGN: Specify the hash algorithm on sign-file command line MODSIGN: Simplify Makefile with a Kconfig helper module: clean up load_module a little more. modpost: Ignore ARC specific non-alloc sections module: constify within_module_* taint: add explicit flag to show whether lock dep is still OK. module: printk message when module signature fail taints kernel.
2013-02-23pm / runtime: force memory allocation with no I/O during Runtime PM callbcackMing Lei
Apply the introduced memalloc_noio_save() and memalloc_noio_restore() to force memory allocation with no I/O during runtime_resume/runtime_suspend callback on device with the flag of 'memalloc_noio' set. Signed-off-by: Ming Lei <ming.lei@canonical.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: Eric Dumazet <eric.dumazet@gmail.com> Cc: David Decotigny <david.decotigny@google.com> Cc: Tom Herbert <therbert@google.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jens Axboe <axboe@kernel.dk> Cc: Minchan Kim <minchan@kernel.org> Cc: Alan Stern <stern@rowland.harvard.edu> Cc: Oliver Neukum <oneukum@suse.de> Cc: Jiri Kosina <jiri.kosina@suse.com> Cc: Mel Gorman <mel@csn.ul.ie> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Michal Hocko <mhocko@suse.cz> Cc: Ingo Molnar <mingo@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: "Rafael J. Wysocki" <rjw@sisk.pl> Cc: Greg KH <greg@kroah.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-02-23pm / runtime: introduce pm_runtime_set_memalloc_noio()Ming Lei
Introduce the flag memalloc_noio in 'struct dev_pm_info' to help PM core to teach mm not allocating memory with GFP_KERNEL flag for avoiding probable deadlock. As explained in the comment, any GFP_KERNEL allocation inside runtime_resume() or runtime_suspend() on any one of device in the path from one block or network device to the root device in the device tree may cause deadlock, the introduced pm_runtime_set_memalloc_noio() sets or clears the flag on device in the path recursively. Signed-off-by: Ming Lei <ming.lei@canonical.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Alan Stern <stern@rowland.harvard.edu> Cc: Oliver Neukum <oneukum@suse.de> Cc: Jiri Kosina <jiri.kosina@suse.com> Cc: Mel Gorman <mel@csn.ul.ie> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Michal Hocko <mhocko@suse.cz> Cc: Ingo Molnar <mingo@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: "Rafael J. Wysocki" <rjw@sisk.pl> Cc: Greg KH <greg@kroah.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: "David S. Miller" <davem@davemloft.net> Cc: Eric Dumazet <eric.dumazet@gmail.com> Cc: David Decotigny <david.decotigny@google.com> Cc: Tom Herbert <therbert@google.com> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-02-23memory-hotplug: check whether all memory blocks are offlined or not when ↵Yasuaki Ishimatsu
removing memory We remove the memory like this: 1. lock memory hotplug 2. offline a memory block 3. unlock memory hotplug 4. repeat 1-3 to offline all memory blocks 5. lock memory hotplug 6. remove memory(TODO) 7. unlock memory hotplug All memory blocks must be offlined before removing memory. But we don't hold the lock in the whole operation. So we should check whether all memory blocks are offlined before step6. Otherwise, kernel maybe panicked. Offlining a memory block and removing a memory device can be two different operations. Users can just offline some memory blocks without removing the memory device. For this purpose, the kernel has held lock_memory_hotplug() in __offline_pages(). To reuse the code for memory hot-remove, we repeat step 1-3 to offline all the memory blocks, repeatedly lock and unlock memory hotplug, but not hold the memory hotplug lock in the whole operation. Signed-off-by: Wen Congyang <wency@cn.fujitsu.com> Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Signed-off-by: Tang Chen <tangchen@cn.fujitsu.com> Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Jiang Liu <jiang.liu@huawei.com> Cc: Jianguo Wu <wujianguo@huawei.com> Cc: Kamezawa Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Wu Jianguo <wujianguo@huawei.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-02-21Merge tag 'usb-3.9-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb Pull USB patches from Greg Kroah-Hartman: "Here's the big USB merge for 3.9-rc1 Nothing major, lots of gadget fixes, and of course, xhci stuff. All of this has been in linux-next for a while, with the exception of the last 3 patches, which were reverts of patches in the tree that caused problems, they went in yesterday." * tag 'usb-3.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb: (190 commits) Revert "USB: EHCI: make ehci-vt8500 a separate driver" Revert "USB: EHCI: make ehci-orion a separate driver" Revert "USB: update host controller Kconfig entries" USB: update host controller Kconfig entries USB: EHCI: make ehci-orion a separate driver USB: EHCI: make ehci-vt8500 a separate driver USB: usb-storage: unusual_devs update for Super TOP SATA bridge USB: ehci-omap: Fix autoloading of module USB: ehci-omap: Don't free gpios that we didn't request USB: option: add Huawei "ACM" devices using protocol = vendor USB: serial: fix null-pointer dereferences on disconnect USB: option: add Yota / Megafon M100-1 4g modem drivers/usb: add missing GENERIC_HARDIRQS dependencies USB: storage: properly handle the endian issues of idProduct testusb: remove all mentions of 'usbfs' usb: gadget: imx_udc: make it depend on BROKEN usb: omap_control_usb: fix compile warning ARM: OMAP: USB: Add phy binding information ARM: OMAP2: MUSB: Specify omap4 has mailbox ARM: OMAP: devices: create device for usb part of control module ...
2013-02-21Merge tag 'driver-core-3.9-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core Pull driver core patches from Greg Kroah-Hartman: "Here is the big driver core merge for 3.9-rc1 There are two major series here, both of which touch lots of drivers all over the kernel, and will cause you some merge conflicts: - add a new function called devm_ioremap_resource() to properly be able to check return values. - remove CONFIG_EXPERIMENTAL Other than those patches, there's not much here, some minor fixes and updates" Fix up trivial conflicts * tag 'driver-core-3.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (221 commits) base: memory: fix soft/hard_offline_page permissions drivercore: Fix ordering between deferred_probe and exiting initcalls backlight: fix class_find_device() arguments TTY: mark tty_get_device call with the proper const values driver-core: constify data for class_find_device() firmware: Ignore abort check when no user-helper is used firmware: Reduce ifdef CONFIG_FW_LOADER_USER_HELPER firmware: Make user-mode helper optional firmware: Refactoring for splitting user-mode helper code Driver core: treat unregistered bus_types as having no devices watchdog: Convert to devm_ioremap_resource() thermal: Convert to devm_ioremap_resource() spi: Convert to devm_ioremap_resource() power: Convert to devm_ioremap_resource() mtd: Convert to devm_ioremap_resource() mmc: Convert to devm_ioremap_resource() mfd: Convert to devm_ioremap_resource() media: Convert to devm_ioremap_resource() iommu: Convert to devm_ioremap_resource() drm: Convert to devm_ioremap_resource() ...
2013-02-20Merge tag 'pm+acpi-3.9-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull ACPI and power management updates from Rafael Wysocki: - Rework of the ACPI namespace scanning code from Rafael J. Wysocki with contributions from Bjorn Helgaas, Jiang Liu, Mika Westerberg, Toshi Kani, and Yinghai Lu. - ACPI power resources handling and ACPI device PM update from Rafael J Wysocki. - ACPICA update to version 20130117 from Bob Moore and Lv Zheng with contributions from Aaron Lu, Chao Guan, Jesper Juhl, and Tim Gardner. - Support for Intel Lynxpoint LPSS from Mika Westerberg. - cpuidle update from Len Brown including Intel Haswell support, C1 state for intel_idle, removal of global pm_idle. - cpuidle fixes and cleanups from Daniel Lezcano. - cpufreq fixes and cleanups from Viresh Kumar and Fabio Baltieri with contributions from Stratos Karafotis and Rickard Andersson. - Intel P-states driver for Sandy Bridge processors from Dirk Brandewie. - cpufreq driver for Marvell Kirkwood SoCs from Andrew Lunn. - cpufreq fixes related to ordering issues between acpi-cpufreq and powernow-k8 from Borislav Petkov and Matthew Garrett. - cpufreq support for Calxeda Highbank processors from Mark Langsdorf and Rob Herring. - cpufreq driver for the Freescale i.MX6Q SoC and cpufreq-cpu0 update from Shawn Guo. - cpufreq Exynos fixes and cleanups from Jonghwan Choi, Sachin Kamat, and Inderpal Singh. - Support for "lightweight suspend" from Zhang Rui. - Removal of the deprecated power trace API from Paul Gortmaker. - Assorted updates from Andreas Fleig, Colin Ian King, Davidlohr Bueso, Joseph Salisbury, Kees Cook, Li Fei, Nishanth Menon, ShuoX Liu, Srinivas Pandruvada, Tejun Heo, Thomas Renninger, and Yasuaki Ishimatsu. * tag 'pm+acpi-3.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (267 commits) PM idle: remove global declaration of pm_idle unicore32 idle: delete stray pm_idle comment openrisc idle: delete pm_idle mn10300 idle: delete pm_idle microblaze idle: delete pm_idle m32r idle: delete pm_idle, and other dead idle code ia64 idle: delete pm_idle cris idle: delete idle and pm_idle ARM64 idle: delete pm_idle ARM idle: delete pm_idle blackfin idle: delete pm_idle sparc idle: rename pm_idle to sparc_idle sh idle: rename global pm_idle to static sh_idle x86 idle: rename global pm_idle to static x86_idle APM idle: register apm_cpu_idle via cpuidle cpufreq / intel_pstate: Add kernel command line option disable intel_pstate. cpufreq / intel_pstate: Change to disallow module build tools/power turbostat: display SMI count by default intel_idle: export both C1 and C1E ACPI / hotplug: Fix concurrency issues and memory leaks ...
2013-02-20Merge tag 'pinctrl-for-v3.9' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl Pull pinctrl changes from Linus Walleij: "These are the main pinctrl changes for the v3.9 merge window. The most interesting change by far is how the device core grabs pinctrl default handles avoiding the need to stick boilerplate into driver consumers. - Grabbing of default pinctrl handles from the device core. These are the hunks hitting drivers/base. All is ACKed by Greg, after a long discussion about different alternatives. - Some stuff also touches the MFD and ARM SoC trees, this has been coordinated and ACKed. - New drivers for: - The Tegra 114 sub-SoC - Allwinner sunxi - New ABx500 driver and sub-SoC drivers for AB8500, AB8505, AB9540 and AB8540. - Make it possible for hogged pins to enter a sleep mode, and make it possible for drivers to control that mode. - Various clean-up, extensions and device tree support to various pin controllers." * tag 'pinctrl-for-v3.9' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl: (68 commits) pinctrl: tegra: add clfvs function to Tegra114 support pinctrl: generic: rename input schmitt disable pinctrl/pinconfig: add debug interface pinctrl: samsung: remove duplicated line ARM: ux500: use real AB8500 IRQ numbers instead of virtual ones ARM: ux500: remove irq_base property from platform_data pinctrl/abx500: use direct IRQ defines pinctrl/abx500: replace IRQ offsets with table read-in values pinctrl/abx500: move IRQ handling to ab8500-core pinctrl: exynos5440: remove erroneous __init pinctrl/abx500: adjust offset for get_mode() pinctrl/abx500: add Device Tree support pinctrl/abx500: align GPIO cluster boundaries pinctrl/abx500: prevent error path from corrupting returning error pinctrl: sunxi: add of_xlate function pinctrl/lantiq: fix pin number in ltq_pmx_gpio_request_enable pinctrl/lantiq: add functionality to falcon_pinconf_dbg_show pinctrl/lantiq: fix pinconfig parameters pinctrl/lantiq: one of the boot leds was defined incorrectly pinctrl/lantiq: only probe available pad controllers ...
2013-02-18base: memory: fix soft/hard_offline_page permissionsFelipe Balbi
those two sysfs files don't have a 'show' method, so they shouldn't have a read permission. Thanks to Greg Kroah-Hartman for actually looking into the source code and figuring out we had a real bug with these two files. Signed-off-by: Felipe Balbi <balbi@ti.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-02-15drivercore: Fix ordering between deferred_probe and exiting initcallsGrant Likely
One of the side effects of deferred probe is that some drivers which used to be probed before initcalls completed are now happening slightly later. This causes two problems. - If a console driver gets deferred, then it may not be ready when userspace starts. For example, if a uart depends on pinctrl, then the uart will get deferred and /dev/console will not be available - __init sections will be discarded before built-in drivers are probed. Strictly speaking, __init functions should not be called in a drivers __probe path, but there are a lot of drivers (console stuff again) that do anyway. In the past it was perfectly safe to do so because all built-in drivers got probed before the end of initcalls. This patch fixes the problem by forcing the first pass of the deferred list to complete at late_initcall time. This is late enough to catch the drivers that are known to have the above issues. Signed-off-by: Grant Likely <grant.likely@secretlab.ca> Tested-by: Haojian Zhuang <haojian.zhuang@linaro.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Russell King <linux@arm.linux.org.uk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: stable <stable@vger.kernel.org> # 3.4+ Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-02-15Merge branch 'pm-cpufreq'Rafael J. Wysocki
* pm-cpufreq: (55 commits) cpufreq / intel_pstate: Fix 32 bit build cpufreq: conservative: Fix typos in comments cpufreq: ondemand: Fix typos in comments cpufreq: exynos: simplify .init() for setting policy->cpus cpufreq: kirkwood: Add a cpufreq driver for Marvell Kirkwood SoCs cpufreq/x86: Add P-state driver for sandy bridge. cpufreq_stats: do not remove sysfs files if frequency table is not present cpufreq: Do not track governor name for scaling drivers with internal governors. cpufreq: Only call cpufreq_out_of_sync() for driver that implement cpufreq_driver.target() cpufreq: Retrieve current frequency from scaling drivers with internal governors cpufreq: Fix locking issues cpufreq: Create a macro for unlock_policy_rwsem{read,write} cpufreq: Remove unused HOTPLUG_CPU code cpufreq: governors: Fix WARN_ON() for multi-policy platforms cpufreq: ondemand: Replace down_differential tuner with adj_up_threshold cpufreq / stats: Get rid of CPUFREQ_STATDEVICE_ATTR cpufreq: Don't check cpu_online(policy->cpu) cpufreq: add imx6q-cpufreq driver cpufreq: Don't remove sysfs link for policy->cpu cpufreq: Remove unnecessary use of policy->shared_type ...
2013-02-14Merge remote-tracking branch 'regmap/topic/no-bus' into regmap-nextMark Brown
2013-02-14Merge remote-tracking branch 'regmap/topic/mmio' into regmap-nextMark Brown
2013-02-14Merge remote-tracking branch 'regmap/topic/irq' into regmap-nextMark Brown
2013-02-14Merge remote-tracking branch 'regmap/topic/flat' into regmap-nextMark Brown
2013-02-14Merge remote-tracking branch 'regmap/topic/debugfs' into regmap-nextMark Brown
2013-02-14Merge remote-tracking branch 'regmap/topic/async' into regmap-nextMark Brown
2013-02-14Merge remote-tracking branch 'regmap/topic/24bit' into regmap-nextMark Brown
2013-02-14regmap: mmio: add register clock supportPhilipp Zabel
Some mmio devices have a dedicated interface clock that needs to be enabled to access their registers. This patch optionally enables a clock before accessing registers in the regmap_bus callbacks. I added (devm_)regmap_init_mmio_clk variants of the init functions that have an added clk_id string parameter. This is passed to clk_get to request the clock from the clk framework. Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2013-02-11regmap: debugfs: Factor out debugfs_tot_len calc into a functionDimitris Papastamos
In preparation to support the regmap debugfs ranges functionality factor this code out to a separate function. We'll need to ensure that the value has been correctly calculated from two separate places in the code. Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2013-02-11regmap: debugfs: Optimize seeking within blocks of registersDimitris Papastamos
Optimize this so that we can better guess where to start scanning from. We know the length of the register field format, therefore given the file pointer position align to the nearest register field and scan from there onwards. We round down in this calculation and we let the rest of the code figure out where to start scanning from. Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>