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path: root/drivers/iio/industrialio-core.c
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* iio: resistance: add IIO_RESISTANCE channel typeMatt Ranostay2015-09-231-0/+1
| | | | | Signed-off-by: Matt Ranostay <mranostay@gmail.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
* iio: chemical: Add IIO_CONCENTRATION channel typeMatt Ranostay2015-09-231-0/+3
| | | | | | | | | | | | | There are air quality sensors that report data back in parts per million of VOC (Volatile Organic Compounds) which are usually indexed from CO2 or another common pollutant. This patchset adds an IIO_CONCENTRATION type that returns a percentage of substance because no other channels types fit this use case. Modifiers for IIO_MOD_CO2 and IIO_MOD_VOC gas types are defined. Signed-off-by: Matt Ranostay <mranostay@gmail.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
* iio: Support triggered eventsVladimir Barinov2015-08-271-2/+2
| | | | | | | | | | Support triggered events. This is useful for chips that don't have their own interrupt sources. It allows to use generic/standalone iio triggers for those drivers. Signed-off-by: Vladimir Barinov <vladimir.barinov@cogentembedded.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
* iio: percolate error if event fd failsLinus Walleij2015-08-161-0/+2
| | | | | | | | | | | | This makes the error from iio_event_getfd() percolate up to userspace properly so we can know for sure there is no events on this device (-ENODEV returned). Before this patch we would bail out looking for the unsupported events on the erroneous (negative) file descriptor. Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Acked-by: Daniel Baluta <daniel.baluta@intel.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
* iio: core: Add function params for kernel docsCristina Opriceana2015-08-021-5/+20
| | | | | | | | | This patch adds the missing fields in kernel docs to remove some warnings that appear when the IIO Documentation DocBook is generated. Signed-off-by: Cristina Opriceana <cristina.opriceana@gmail.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
* iio: Add missing modifier names to corePeter Meerwald2015-06-211-0/+8
| | | | | | | | some are documented, others are in iio_event_monitor.c which was recently moved from staging Signed-off-by: Peter Meerwald <pmeerw@pmeerw.net> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
* iio: Add I/Q modifiersLars-Peter Clausen2015-05-231-0/+2
| | | | | | | | | | | I/Q modifiers can be used to denote signals which are represented by a in-phase and a quadrature component. The ABI documentation describes the I and Q modifiers for current and voltage channels for now as those will be the most likely users. Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
* iio: core: add high pass filter attributesMartin Fuzzey2015-05-171-0/+2
| | | | | | | | | | Add a high pass filter attribute for measurements (like the existing low pass) Also add both high and low pass attributes for events. Signed-off-by: Martin Fuzzey <mfuzzey@parkeon.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
* iio: core: Introduce IIO_CHAN_INFO_OVERSAMPLING_RATIOIrina Tirdea2015-05-101-0/+1
| | | | | | | | | | | | | Some magnetometers can perform a number of repetitions in HW for each measurement to increase accuracy. One example is Bosch BMC150: http://ae-bst.resource.bosch.com/media/products/dokumente/bmc150/BST-BMC150-DS000-04.pdf. Introduce an interface to set the oversampling ratio for these devices. Signed-off-by: Irina Tirdea <irina.tirdea@intel.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
* iio: core: Introduce IIO_CHAN_INFO_CALIBEMISSIVITYVianney le Clément de Saint-Marcq2015-04-091-0/+1
| | | | | | | | | | | | | | | | | Contact-less IR temperature sensors measure the temperature of an object by using its thermal radiation. Surfaces with different emissivity ratios emit different amounts of energy at the same temperature. IIO_CHAN_INFO_CALIBEMISSIVITY allows the user to inform the sensor of the emissivity of the object in front of it, in order to effectively measure its temperature. A device providing such setting is Melexis's MLX90614: http://melexis.com/Assets/IR-sensor-thermometer-MLX90614-Datasheet-5152.aspx. Signed-off-by: Vianney le Clément de Saint-Marcq <vianney.leclement@essensium.com> Cc: Arnout Vandecappelle (Essensium/Mind) <arnout@mind.be> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
* iio: core: Fix double free.Martin Fuzzey2015-03-141-2/+3
| | | | | | | | | | | | | | | | | | | | | | When an error occurred during event registration memory was freed twice resulting in kernel memory corruption and a crash in unrelated code. The problem was caused by iio_device_unregister_eventset() iio_device_unregister_sysfs() being called twice, once on the error path and then again via iio_dev_release(). Fix this by making these two functions idempotent so they may be called multiple times. The problem was observed before applying 78b33216 iio:core: Handle error when mask type is not separate Signed-off-by: Martin Fuzzey <mfuzzey@parkeon.com> Cc: <Stable@vger.kernel.org> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
* iio: core: Introduce IIO_CHAN_INFO_DEBOUNCE_COUNT and _TIMEIrina Tirdea2015-01-291-0/+2
| | | | | | | | | | | | | | | | | | | | | The pedometer needs to filter out false steps that might be generated by tapping the foot, sitting, etc. To do that it computes the number of steps that occur in a given time and decides the user is moving only if this value is over a threshold. E.g.: the user starts moving only if he takes 4 steps in 3 seconds. This filter is applied only when the user starts moving. A device that has such pedometer functionality is Freescale's MMA9553L: http://www.freescale.com/files/sensors/doc/ref_manual/MMA9553LSWRM.pdf. To export this feature, this patch introduces IIO_CHAN_INFO_DEBOUNCE_COUNT and IIO_CHAN_INFO_DEBOUNCE_TIME. For the pedometer, in_steps_debounce_count will specify the number of steps that need to occur in in_steps_debounce_time seconds so that the pedometer decides the user is moving. Signed-off-by: Irina Tirdea <irina.tirdea@intel.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
* iio: core: Introduce IIO_CHAN_INFO_CALIBWEIGHTIrina Tirdea2015-01-271-0/+1
| | | | | | | | | | Some devices need the weight of the user to compute other parameters. One of this devices is Freescale's MMA9553L (http://www.freescale.com/files/sensors/doc/ref_manual/MMA9553LSWRM.pdf) that needs the weight of the user to compute the number of calories burnt. Signed-off-by: Irina Tirdea <irina.tirdea@intel.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
* iio: core: Introduce IIO_VELOCITY and IIO_MOD_ROOT_SUM_SQUARED_X_Y_ZIrina Tirdea2015-01-271-0/+2
| | | | | | | | | | | | | | | Some devices export the current speed value of the user. One of this devices is Freescale's MMA9553L (http://www.freescale.com/files/sensors/doc/ref_manual/MMA9553LSWRM.pdf) that computes the speed of the user based on the number of steps and stride length. Introduce a new channel type VELOCITY and a modifier for the magniture or norm of the velocity vector, IIO_MOD_ROOT_SUM_SQUARED_X_Y_Z. Signed-off-by: Irina Tirdea <irina.tirdea@intel.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
* iio: core: Introduce DISTANCE channel typeIrina Tirdea2015-01-271-0/+1
| | | | | | | | | | | | | | Some devices export an estimation of the distance the user has covered since the last reset. One of this devices is Freescale's MMA9553L (http://www.freescale.com/files/sensors/doc/ref_manual/MMA9553LSWRM.pdf) that computes the distance based on the stride length and step rate. Introduce a new channel type DISTANCE to export these values. Signed-off-by: Irina Tirdea <irina.tirdea@intel.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
* iio: core: Introduce ENERGY channel typeIrina Tirdea2015-01-271-0/+1
| | | | | | | | | | | | Human activity sensors report the energy burnt by the user. One of this devices is Freescale's MMA9553L (http://www.freescale.com/files/sensors/doc/ref_manual/MMA9553LSWRM.pdf) that computes the number of calories based on weight and step rate. Introduce a new channel type ENERGY to export these values. Signed-off-by: Irina Tirdea <irina.tirdea@intel.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
* iio: ensure scan index is unique at device registerVlad Dogaru2015-01-051-0/+27
| | | | | | | | | | Having two or more channels with the same positive scan_index field makes no sense if the device supports buffering. Prevent this situation by failing to register such a device. Signed-off-by: Vlad Dogaru <vlad.dogaru@intel.com> Reviewed-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
* iio: core: Get rid of misleading commentKarol Wrona2014-12-261-1/+0Star
| | | | | | | | This comment did not fit here. It explains why devm_kmalloc uses dr_alloc. Generally is not needed at all. Signed-off-by: Karol Wrona <k.wrona@samsung.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
* iio: Move buffer registration to the coreLars-Peter Clausen2014-12-121-1/+13
| | | | | | | | | | | | | | | | | | | | | | | | | Originally device and buffer registration were kept as separate operations in IIO to allow to register two distinct sets of channels for buffered and non-buffered operations. This has since already been further restricted and the channel set registered for the buffer needs to be a subset of the channel set registered for the device. Additionally the possibility to not have a raw (or processed) attribute for a channel which was registered for the device was added a while ago. This means it is possible to not register any device level attributes for a channel even if it is registered for the device. Also if a channel's scan_index is set to -1 and the channel is registered for the buffer it is ignored. So in summary it means it is possible to register the same channel array for both the device and the buffer yet still end up with distinctive sets of channels for both of them. This makes the argument for having to have to manually register the channels for both the device and the buffer invalid. Considering that the vast majority of all drivers want to register the same set of channels for both the buffer and the device it makes sense to move the buffer registration into the core to avoid some boiler-plate code in the device driver setup path. Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
* iio: core: Introduce IIO_CHAN_INFO_CALIBHEIGHTIrina Tirdea2014-11-221-0/+1
| | | | | | | | | | | | Some devices need the height of the user to compute various parameters. One of this devices is Freescale's MMA9553L (http://www.freescale.com/files/sensors/doc/ref_manual/MMA9553LSWRM.pdf) that needs the height of the user to compute the stride length which is used further to determine distance, speed and activity type. Signed-off-by: Irina Tirdea <irina.tirdea@intel.com> Signed-off-by: Daniel Baluta <daniel.baluta@intel.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
* iio: core: Introduce STEPS channel, ENABLE mask and INSTANCE eventIrina Tirdea2014-11-221-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | These changes are needed to support the functionality of a pedometer. A pedometer has two basic functionalities: step counter and step detector. The step counter needs to be enabled and then it will count the steps in its hardware register. Whenever the application needs to check the step count, it will read the step counter register. To support the step counter a new channel type STEPS is added. Since the pedometer needs to be enabled first so that the hardware can count and store the steps, we need a specific ENABLE channel info mask. The step detector will generate an interrupt each time a step is detected. To support this functionality we add a new event type INSTANCE. For more information on the Android requirements for step counter and step detector see: http://source.android.com/devices/sensors/composite_sensors.html#counter and http://source.android.com/devices/sensors/composite_sensors.html#detector. A device that has the pedometer functionality this interface needs to support is Freescale's MMA9553L: http://www.freescale.com/files/sensors/doc/ref_manual/MMA9553LSWRM.pdf Signed-off-by: Irina Tirdea <irina.tirdea@intel.com> Signed-off-by: Daniel Baluta <daniel.baluta@intel.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
* iio: core: Introduce IIO_ACTIVITY channelDaniel Baluta2014-11-221-0/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This channel will be used for exposing information about activity composite sensors. Activities supported so far: * running * jogging * walking * still THRESHOLD event is used to signal a change in the activity state. We associate a confidence interval for each activity expressed as a percentage from 0 to 100. * 0, means the sensor IS NOT reporting that activity. * 100, means the sensor IS reporting that activity. Users of this interface have two possible means to gather information about the ongoing activities. 1. Event based, via event file descriptor * sensor may report an event when ENTERING an activity or LEAVING an activity based on a threshold value. * drivers will wake up applications waiting data on the event fd 2. Polling, by reading the sysfs associated attribute files: * /sys/bus/iio/devices/iio:device0/in_activity_running_input expressed as percentage confidence value from 0 to 100. This will offer an interface for Android significant motion composite sensor defined here: http://source.android.com/devices/sensors/composite_sensors.html Activities listed above are supported by Freescale's MMA9553 sensor: http://freescale.com/files/sensors/doc/ref_manual/MMA9553LSWRM.pdf Signed-off-by: Irina Tirdea <irina.tirdea@intel.com> Signed-off-by: Daniel Baluta <daniel.baluta@intel.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
* iio: types: Added support for rotation from north usage attributesReyad Attiyat2014-07-201-0/+4
| | | | | | | | Added the rotation from north usage attributes to the iio modifier enum and to the iio modifier names array. Signed-off-by: Reyad Attiyat <reyad.attiyat@gmail.com> Acked-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
* iio: Add TEMP_AMBIENT and TEMP_OBJECT channel modifiersPeter Meerwald2014-05-031-0/+2
| | | | | | | | useful for contactless temperature sensors to distinguish between the ambient temperature and the temperature of the object Signed-off-by: Peter Meerwald <pmeerw@pmeerw.net> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
* IIO: core: Add quaternion modifierSrinivas Pandruvada2014-04-291-0/+1
| | | | | | | Added quaternion in the list of supported modifiers. Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
* IIO: core: Introduce read_raw_multiSrinivas Pandruvada2014-04-291-22/+43
| | | | | | | | | | | | | | This callback is introduced to overcome some limitations of existing read_raw callback. The functionality of both existing read_raw and read_raw_multi is similar, both are used to request values from the device. The current read_raw callback allows only two return values. The new read_raw_multi allows returning multiple values. Instead of passing just address of val and val2, it passes length and pointer to values. Depending on the type and length of passed buffer, iio client drivers can return multiple values. Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
* iio:core: Fix bug in length of event info_mask and catch unhandled bits set ↵Jonathan Cameron2014-03-161-0/+2
| | | | | | | | | | | | | | | | | | | | in masks. The unhandled bits case was highlighted by smatch: CHECK drivers/iio/industrialio-core.c drivers/iio/industrialio-core.c:719 iio_device_add_info_mask_type() error: buffer overflow 'iio_chan_info_postfix' 17 <= 31 CC [M] drivers/iio/industrialio-core.o CHECK drivers/iio/industrialio-event.c drivers/iio/industrialio-event.c:327 iio_device_add_event() error: buffer overflow 'iio_ev_info_text' 3 <= 3 The incorrect limit for the for_each_set_bit loop was noticed whilst fixing this other case. Note that as we only have 3 possible entries a the moment and the value was set to 4, the bug would not have any effect currently. It will bite fairly soon though, so best fix it now. Signed-off-by: Jonathan Cameron <jic23@kernel.org> Cc: Lars-Peter Clausen <lars@metafoo.de> Cc: Dan Carpenter <dan.carpenter@oracle.com>
* iio: force snprintf for PAGE_SIZE bufsKees Cook2014-03-151-2/+2
| | | | | | | | | | This is a tiny preventative measure to make sure we can't write beyond PAGE_SIZE on the buffers being used in sysfs for iio. There is currently no way for this to happen, but the change makes this code more robust for the future. Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
* iio: Avoid unnecessary kasprintfLars-Peter Clausen2014-02-181-26/+13Star
| | | | | | | | | | | | | | | | | | | name_format already contains the final name and no format characters. So the code basically reads: dev_attr->attr.name = kstrdup(GFP_KERNEL, name_format); if (dev_attr->attr.name == NULL) ... kfree(name_format); Which means we can save one alloc and free pair per attribute name if we directly assign name_format to dev_attr->attr.name. The patch also renames name_format to name to denote that this is indeed the final name and has no format characters in it. Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
* iio: Don't include extended name in shared attributesLars-Peter Clausen2014-02-181-1/+1
| | | | | | | | The extended name is channel specific and should not be included in shared attributes. Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
* iio get rid of unneccessary error_retHartmut Knaack2014-02-181-7/+3Star
| | | | | | | Get rid of obsolete uses of goto error_ret and some empty lines. Signed-off-by: Hartmut Knaack <knaack.h@gmx.de> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
* iio: Add support for humidity sensorsHarald Geyer2013-12-031-0/+1
| | | | | | | | There are already humidity sensors in the hwmon subsystem, so we use their unit (milli percent) here as well. Signed-off-by: Harald Geyer <harald@ccbib.org> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
* iio: core: Move kernel doc to the right locationSachin Kamat2013-11-241-0/+42
| | | | | | | | | Documentation related to function should be placed above its implementation. Move it accordingly. Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org> Cc: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
* iio: core: Implement devm_iio_device_{register,unregister}Sachin Kamat2013-11-241-0/+59
| | | | | | | | | | | | Add device managed devm_iio_device_{register,unregister}() to automatically unregister IIO drivers thus leading to simplified IIO driver code. Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org> Cc: Lars-Peter Clausen <lars@metafoo.de> Tested-by: Lars-Peter Clausen <lars@metafoo.de> Reviewed-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
* iio: core: Add misssing bracesSachin Kamat2013-10-241-1/+1
| | | | | | | | Silences the following checkpatch warning: WARNING: sizeof *iio_attr should be sizeof(*iio_attr) Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
* iio: core: Use pr_err instead of printkSachin Kamat2013-10-241-6/+5Star
| | | | | | | Use of pr_err is preferred to printk. Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
* iio: Factor IIO value formating into its own functionLars-Peter Clausen2013-10-121-12/+26
| | | | | Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
* iio: Add a helper to free a list of IIO device attributesLars-Peter Clausen2013-10-121-16/+18
| | | | | | | | | | | We have the same code to free a IIO device attribute list in multiple place. This patch adds a new helper function to take care of this and replaces the custom instances with a call to the helper function. Note that we do not need to call list_del() for each of the list items since we will never look at any of the list items nor the list itself again. Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
* iio: Wakeup poll and blocking reads when the device is unregisteredLars-Peter Clausen2013-10-121-0/+4
| | | | | | | | | Once the device has been unregistered there won't be any new data no matter how long a userspace application waits, so we might as well wake them up and let them know. Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
* iio: Return -ENODEV for file operations if the device has been unregisteredLars-Peter Clausen2013-10-121-0/+3
| | | | | | | | | If the IIO device has been unregistered return -ENODEV for any further file operations like read() and ioctl(). This avoids userspace being able to grab new references to the device. Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
* iio: Add reference counting for buffersLars-Peter Clausen2013-10-121-0/+3
| | | | | | | | | | | | | | | | | | | | | Since the buffer is accessed by userspace we can not just free the buffers memory once we are done with it in kernel space. There might still be open file descriptors and userspace still might be accessing the buffer. This patch adds support for reference counting to the IIO buffers. When a buffer is created and initialized its initial reference count is set to 1. Instead of freeing the memory of the buffer the buffer's _free() function will drop that reference again. But only after the last reference to the buffer has been dropped the buffer the buffer's memory will be freed. The IIO device will take a reference to its primary buffer. The patch adds a small helper function for this called iio_device_attach_buffer() which will get a reference to the buffer and assign the buffer to the IIO device. This function must be used instead of assigning the buffer to the device by hand. The reference is only dropped once the IIO device is freed and we can be sure that there are no more open file handles. A reference to a buffer will also be taken whenever the buffer is active to avoid the buffer being freed while data is still being send to it. Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
* Merge 3.12-rc4 into staging-nextGreg Kroah-Hartman2013-10-071-1/+1
|\ | | | | | | | | | | We want the staging fixes in this branch as well. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * iio: Remove debugfs entries in iio_device_unregister()Lars-Peter Clausen2013-09-301-1/+1
| | | | | | | | | | | | | | | | | | Remove the the debugfs entries in iio_device_unregister(). Otherwise the debugfs entries might still be accessible even though the device used in the debugfs callback has already been freed. Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
* | Merge 3.12-rc2 into staging-next.Greg Kroah-Hartman2013-09-251-10/+21
|\| | | | | | | | | | | | | | | This resolves the merge problem with two iio drivers that Stephen Rothwell pointed out. Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * iio: Prevent race between IIO chardev opening and IIO device freeLars-Peter Clausen2013-09-211-9/+12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Set the IIO device as the parent for the character device We need to make sure that the IIO device is not freed while the character device exists, otherwise the freeing of the IIO device might race against the file open callback. Do this by setting the character device's parent to the IIO device, this will cause the character device to grab a reference to the IIO device and only release it once the character device itself has been removed. Also move the registration of the character device before the registration of the IIO device to avoid the (rather theoretical case) that the IIO device is already freed again before we can add the character device and grab a reference to the IIO device. We also need to move the call to cdev_del() from iio_dev_release() to iio_device_unregister() (where it should have been in the first place anyway) to avoid a reference cycle. As iio_dev_release() is only called once all reference are dropped, but the character device holds a reference to the IIO device. Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
| * iio: fix: Keep a reference to the IIO device for open file descriptorsLars-Peter Clausen2013-09-211-0/+4
| | | | | | | | | | | | | | | | Make sure that the IIO device is not freed while we still have file descriptors for it. Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
| * iio: Stop sampling when the device is removedLars-Peter Clausen2013-09-211-1/+5
| | | | | | | | | | | | | | | | Make sure to stop sampling when the device is removed, otherwise it will continue to sample forever. Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
* | iio: add info_mask_[shared_by_dir/shared_by_all]Jonathan Cameron2013-09-151-0/+30
| | | | | | | | | | | | | | | | | | | | | | These two additional info_mask bitmaps should allow all 'standard' numeric attributes to be handled using the read_raw and write_raw callbacks. Whilst this should reduce code, the more important element is that this makes these values easily accessible to in kernel users of IIO devices. Signed-off-by: Jonathan Cameron <jic23@kernel.org> Reviewed-by: Lars-Peter Clausen <lars@metafoo.de>
* | iio: refactor info mask and ext_info attribute creation.Jonathan Cameron2013-09-151-69/+80
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Introduce an enum to specify whether the attribute is separate or shared. Factor out the bitmap handling for loop into a separate function. Tidy up error handling and add a NULL assignment to squish a false positive warning from GCC. Change ext_info shared type from boolean to enum and update in all drivers. Signed-off-by: Jonathan Cameron <jic23@kernel.org> Reviewed-by: Lars-Peter Clausen <lars@metafoo.de>
* | iio: Add INT_TIME (integration time) channel info attributePeter Meerwald2013-09-141-0/+1
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Integration time is in seconds; it controls the measurement time and influences the gain of a sensor. There are two typical ways that scaling is implemented in a device: 1) input amplifier, 2) reference to the ADC is changed. These both result in the accuracy of the ADC varying (by applying its sampling over a more relevant range). Integration time is a way of dealing with noise inherent in the analog sensor itself. In the case of a light sensor, a mixture of photon noise and device specific noise. Photon noise is dealt with by either improving the efficiency of the sensor, (more photons actually captured) which is not easily varied dynamically, or by integrating the measurement over a longer time period. Note that this can also be thought of as an averaging of a number of individual samples and is infact sometimes implemented this way. Altering integration time implies that the duration of a measurement changes, a fact the device's user may be interested in. Hence it makes sense to distinguish between integration time and simple scale. In some devices both types of control are present and whilst they will have similar effects on the amplitude of the reading, their effect on the noise of the measurements will differ considerably. Used by adjd_s311, tsl4531, tcs3472 The following drivers have similar controls (and could be adapted): * tsl2563 (integration time is controlled via CALIBSCALE among other things) * tsl2583 (has integration_time device_attr, but driver doesn't use channels yet) * tsl2x7x (has integration_time attr) Signed-off-by: Peter Meerwald <pmeerw@pmeerw.net> Cc: Jon Brenner <jon.brenner@ams.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
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