Commit Graph

28 Commits

Author SHA1 Message Date
Jonathan Cameron d26c9abeed iio: adc: xilinx-xadc: use devm_platform_ioremap_resource
Reduces local boilerplate.
Suggested by coccinelle.
 CHECK   drivers/iio/adc/xilinx-xadc-core.c
drivers/iio/adc/xilinx-xadc-core.c:1184:1-11: WARNING: Use devm_platform_ioremap_resource for xadc -> base

Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Cc: Manish Narani <manish.narani@xilinx.com>
Reviewed-by: Sven Van Asbroeck <TheSven73@gmail.com>
2019-10-18 20:05:58 +01:00
Thomas Gleixner fda8d26e61 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 177
Based on 1 normalized pattern(s):

  licensed under the gpl 2

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-only

has been chosen to replace the boilerplate/reference in 135 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Reviewed-by: Alexios Zavras <alexios.zavras@intel.com>
Reviewed-by: Steve Winslow <swinslow@gmail.com>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190528170026.071193225@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-30 11:29:19 -07:00
Sven Van Asbroeck 2e4b88f739 iio: adc: xilinx: prevent touching unclocked h/w on remove
In remove, the clock is disabled before canceling the
delayed work. This means that the delayed work may be
touching unclocked hardware.

Fix by disabling the clock after the delayed work is
fully canceled. This is consistent with the probe error
path order.

Signed-off-by: Sven Van Asbroeck <TheSven73@gmail.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2019-03-16 15:49:56 +00:00
Sven Van Asbroeck 862e4644fd iio: adc: xilinx: fix potential use-after-free on probe
If probe errors out after request_irq(), its error path
does not explicitly cancel the delayed work, which may
have been scheduled by the interrupt handler.

This means the delayed work may still be running when
the core frees the private structure (struct xadc).
This is a potential use-after-free.

Fix by inserting cancel_delayed_work_sync() in the probe
error path.

Signed-off-by: Sven Van Asbroeck <TheSven73@gmail.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2019-03-16 15:48:51 +00:00
Sven Van Asbroeck 62039b6aef iio: adc: xilinx: fix potential use-after-free on remove
When cancel_delayed_work() returns, the delayed work may still
be running. This means that the core could potentially free
the private structure (struct xadc) while the delayed work
is still using it. This is a potential use-after-free.

Fix by calling cancel_delayed_work_sync(), which waits for
any residual work to finish before returning.

Signed-off-by: Sven Van Asbroeck <TheSven73@gmail.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2019-03-16 15:48:30 +00:00
Aditya Pakki 7fc93f3285 iio: adc: xilinx: check return value of xadc_write_adc_reg
In function xadc_probe, xadc_write_adc_reg can return an error value
when write fails. The fix checks for the return value consistent with
other invocations of the latter function.

Signed-off-by: Aditya Pakki <pakki001@umn.edu>
Reviewed-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2019-01-05 16:44:02 +00:00
Manish Narani 2fa03b92b6 iio: adc: xilinx: Move request_irq before enabling interrupts
Enabling the Interrupts before registering the irq handler is a bad
idea. This patch corrects the same for XADC driver.

Signed-off-by: Manish Narani <manish.narani@xilinx.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2018-07-29 13:30:35 +01:00
Manish Narani 50e8e9f309 iio: adc: xilinx: Remove platform_get_irq from xadc_remove function
This patch avoids getting irq number in xadc_remove function. Instead
store 'irq' in xadc struct and use xadc->irq wherever needed.
This patch also resolves a warning reported by coverity where it asks to
check return value of platform_get_irq() for any errors in xadc_remove.

Signed-off-by: Manish Narani <manish.narani@xilinx.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2018-07-29 12:52:21 +01:00
Manish Narani 81f5471838 iio: adc: xilinx: limit pcap clock frequency value
This patch limits the xadc pcap clock frequency value to be less than
200MHz. This fixes the issue when zynq is booted at higher frequency
values, pcap crosses the maximum limit of 200MHz(Fmax) as it is derived
from IOPLL.
If this limit is crossed it is required to alter the WEDGE and REDGE
bits of XADC_CFG register to make timings better in the interface. So to
avoid alteration of these bits every time, the pcap value should not
cross the Fmax limit.

Signed-off-by: Manish Narani <manish.narani@xilinx.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2018-07-29 12:49:48 +01:00
Manish Narani 0a8460966f iio: adc: xilinx: Check for return values in clk related functions
This patch adds check for return values from clock related functions.
This was reported by static code analysis tool.

Signed-off-by: Manish Narani <manish.narani@xilinx.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2018-07-29 12:46:38 +01:00
Manish Narani c344a327ba iio: adc: xilinx: Remove dead code from xadc_zynq_setup
This patch removes dead code from xadc_zynq_setup. The condition
"if (tck_rate > XADC_ZYNQ_TCK_RATE_MAX)" cannot be true at any point of
time. There is also an incompatible parameter used in the code.
This patch fixes the same reported by coverity.

Signed-off-by: Manish Narani <manish.narani@xilinx.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2018-07-23 19:18:11 +01:00
Jonathan Cameron 52b31bcc93 iio:adc: drop assign iio_info.driver_module and iio_trigger_ops.owner
The equivalent of both of these are now done via macro magic when
the relevant register calls are made.  The actual structure
elements will shortly go away.

Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Lars-Peter Clausen <lars@metafoo.de>
2017-08-22 21:22:25 +01:00
Arvind Yadav 0a178fd732 iio: adc: xilinx: Handle return value of clk_prepare_enable
clk_prepare_enable() can fail here and we must check its return value.

Signed-off-by: Arvind Yadav <arvind.yadav.cs@gmail.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-06-03 09:55:23 +01:00
Christophe JAILLET ca1c39ef76 iio: adc: xilinx: Fix error handling
Reorder error handling labels in order to match the way resources have
been allocated.

Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Acked-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-02-25 16:39:32 +00:00
Greg Kroah-Hartman f3cf3fb7ec First set of new device support, features and cleanups for IIO in the 4.5 cycle
Usual mixed bag, but the big item perhaps in this series is the DMA buffer
 support added by Lars-Peter Clausen. It's been in the works for a long time
 and it will be interesting to see what hardware support shows up now that
 this is available.
 
 New core features + associate cleanup.
 * Add generic DMA buffer infrastructure
 * Add a DMAengine framework based buffer
  Also associated minor changes.
    - Set the device buffer watermark based on the minimum watermark for all
      attached buffers rather than just the 'primary' one.
    - iio_buffer_init - only set the watermark default if one hasn't already
      been provided.  This allows simple support for devices with a fixed
      watermark.
    - read only attribute for watermark on fixed watermark devices.
    - add explicit buffer enable/disable callbacks to allow the buffer to
      do more than trivial actions when it is being turned on and off.
 * IIO_VAL_INT support in write_raw_get_fmt function.
 
 New device support
 * Freescale MMA7455/7456L accelerometers
 * Memsic MXC6255XC accelerometer
 * ST lis2dh12 accelerometer
 * TI ADS8688 ADC
 * TI Palamas (twl6035/7) gpadc
 
 New driver features
 * mma8452
   - support either of the available interrupt pins to cope with the case
     where board layout has lead to a particular one being connected.
 
 Staging graduation
 * Dummy driver
   - this driver acts as both an example and a test device for those with
     out hardware to develop userspace code against.
 
 Cleanups and minor bits and bobs.
 * treewide
   - Sort out the ordering of iio_device_register/unregister vs runtime
     pm function calls so that it's all nice and consistent and not race
     prone.
   - Check sscanf return values.  None of the cases will actually happen as
     the strings are supplied internally, but best to be consistent on this.
 * ad7780
   - switch over to the gpio descriptor interface and remove the now unused
     platform data which gets rid of a header entirely.
 * ad7793
   - drop a pointless else statement.
 * at91_adc
   - Swap kmalloc_array in for a kmalloc doing the same job.
 * dummy
   - get rid of some commented out lines that snuck in during the move of
     the driver.
 * lm3533-als
   - Print an error message on provision of an invalid resistance.
 * mcp320x
   - Add compatible strings with vendor prefix and deprecate those with
     no vendor prefix.
 * mxs-lradc
   - Use BIT macro in various places rather than shifted ones.
 * pa12203001
   - Power off the chip if the registration fails.
 * pulsedlight-lidar-lite
   - add runtime PM support.
 * xilinx XADC
   - constify an iio_buffer_setup_ops structure.
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Merge tag 'iio-for-4.5a' of git://git.kernel.org/pub/scm/linux/kernel/git/jic23/iio into staging-next

Jonathan writes:

First set of new device support, features and cleanups for IIO in the 4.5 cycle

Usual mixed bag, but the big item perhaps in this series is the DMA buffer
support added by Lars-Peter Clausen. It's been in the works for a long time
and it will be interesting to see what hardware support shows up now that
this is available.

New core features + associate cleanup.
* Add generic DMA buffer infrastructure
* Add a DMAengine framework based buffer
 Also associated minor changes.
   - Set the device buffer watermark based on the minimum watermark for all
     attached buffers rather than just the 'primary' one.
   - iio_buffer_init - only set the watermark default if one hasn't already
     been provided.  This allows simple support for devices with a fixed
     watermark.
   - read only attribute for watermark on fixed watermark devices.
   - add explicit buffer enable/disable callbacks to allow the buffer to
     do more than trivial actions when it is being turned on and off.
* IIO_VAL_INT support in write_raw_get_fmt function.

New device support
* Freescale MMA7455/7456L accelerometers
* Memsic MXC6255XC accelerometer
* ST lis2dh12 accelerometer
* TI ADS8688 ADC
* TI Palamas (twl6035/7) gpadc

New driver features
* mma8452
  - support either of the available interrupt pins to cope with the case
    where board layout has lead to a particular one being connected.

Staging graduation
* Dummy driver
  - this driver acts as both an example and a test device for those with
    out hardware to develop userspace code against.

Cleanups and minor bits and bobs.
* treewide
  - Sort out the ordering of iio_device_register/unregister vs runtime
    pm function calls so that it's all nice and consistent and not race
    prone.
  - Check sscanf return values.  None of the cases will actually happen as
    the strings are supplied internally, but best to be consistent on this.
* ad7780
  - switch over to the gpio descriptor interface and remove the now unused
    platform data which gets rid of a header entirely.
* ad7793
  - drop a pointless else statement.
* at91_adc
  - Swap kmalloc_array in for a kmalloc doing the same job.
* dummy
  - get rid of some commented out lines that snuck in during the move of
    the driver.
* lm3533-als
  - Print an error message on provision of an invalid resistance.
* mcp320x
  - Add compatible strings with vendor prefix and deprecate those with
    no vendor prefix.
* mxs-lradc
  - Use BIT macro in various places rather than shifted ones.
* pa12203001
  - Power off the chip if the registration fails.
* pulsedlight-lidar-lite
  - add runtime PM support.
* xilinx XADC
  - constify an iio_buffer_setup_ops structure.
2015-12-01 09:13:29 -08:00
Greg Kroah-Hartman 819db468b2 First set of IIO fixes for the 4.4 cycle.
This set does not include those for issues introduced during the merge
 window.  Fixes of those will follow in a future series.
 
 * ad5064
   - Make sure the local i2c_write returns 0 on success rather than the
     number of bytes transfered.  Otherwise we report an error on all writes.
   - Fix a shift for ad5629 and ad5669 which gives incorrect DAC output on
     these parts.
 * ad7793
   - The product ID on the datasheet is wrong.  Fix it in the driver.
 * IIO_DUMMY_EVGEN
   - select IRQ_WORK as a dependency.
 * lpc32xx
   - make sure clock is prepared before enabling.
 * si7020
   - data byte order was reversed. Fix it.
 * vf610
   - Internal temperature calculation was wrong if a different
     reference voltage was used.  Now use a linear interpolation
     function to make it work over the full range.
   - Fix a division by zero in the case of a device tree property
     not being present (same issue two fixes).
 * xilinx XADC
   - VREFN scale was wrong - fix it.
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Merge tag 'iio-fixes-for-4.4a' of ssh://ra.kernel.org/pub/scm/linux/kernel/git/jic23/iio into staging-linus

Jonathan writes:

First set of IIO fixes for the 4.4 cycle.

This set does not include those for issues introduced during the merge
window.  Fixes of those will follow in a future series.

* ad5064
  - Make sure the local i2c_write returns 0 on success rather than the
    number of bytes transfered.  Otherwise we report an error on all writes.
  - Fix a shift for ad5629 and ad5669 which gives incorrect DAC output on
    these parts.
* ad7793
  - The product ID on the datasheet is wrong.  Fix it in the driver.
* IIO_DUMMY_EVGEN
  - select IRQ_WORK as a dependency.
* lpc32xx
  - make sure clock is prepared before enabling.
* si7020
  - data byte order was reversed. Fix it.
* vf610
  - Internal temperature calculation was wrong if a different
    reference voltage was used.  Now use a linear interpolation
    function to make it work over the full range.
  - Fix a division by zero in the case of a device tree property
    not being present (same issue two fixes).
* xilinx XADC
  - VREFN scale was wrong - fix it.
2015-11-18 13:15:50 -08:00
Julia Lawall cef7e12585 iio: adc: xilinx: constify iio_buffer_setup_ops structure
The iio_buffer_setup_ops structures are never modified, so declare this one
as const, like the others.

Done with the help of Coccinelle.

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Acked-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2015-11-18 19:04:01 +00:00
Thomas Betker a57f8dac46 iio: adc: xilinx: Fix VREFN scale
The scaling factor for VREFN is 3.0/4096 (not 1.0/4096), just as for
VREFP. This is not immediately obvious from the specification (Xilinx
UG480), but has been confirmed by Xilinx support.

Suggested-by: Hartmut Knaack <knaack.h@gmx.de>
Signed-off-by: Thomas Betker <thomas.betker@rohde-schwarz.com>
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2015-11-15 12:36:20 +00:00
Xander Huff 70581e0ef8 iio: adc: xilinx-xadc: Push interrupts into hardirq context
The driver currently registers a pair of irq handlers using
request_threaded_irq(), however the synchronization mechanism between the
hardirq and the threadedirq handler is a regular spinlock.

Unfortunately, this breaks PREEMPT_RT builds, where a spinlock can sleep,
and is thus not able to be acquired from a hardirq handler. This patch gets
rid of the threaded handler and pushes all interrupt handling into the
hardirq context, and uses request_irq().

To validate that this change has no impact on RT performance, here are
cyclictest values with no processes running:

$ sudo cyclictest -S -m -p 98
policy: fifo: loadavg: 0.00 0.01 0.05 1/174 2539
T: 0 ( 1405) P:98 I:1000 C:167010520 Min: 9 Act: 12 Avg: 12 Max: 75
T: 1 ( 1862) P:98 I:1500 C:111340339 Min: 9 Act: 12 Avg: 12 Max: 73

Then, all xadc raw handles were accessed in a continuous loop via
/sys/bus/iio/devices/iio:device0:

$ sudo cyclictest -S -m -p 98
policy: fifo: loadavg: 7.84 7.70 7.63 3/182 4260
T: 0 ( 2559) P:98 I:1000 C:241557018 Min: 11 Act: 18 Avg: 21 Max: 74
T: 1 ( 2560) P:98 I:1500 C:161038006 Min: 10 Act: 21 Avg: 20 Max: 73

Signed-off-by: Xander Huff <xander.huff@ni.com>
Acked-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2015-08-16 10:51:27 +01:00
Thomas Betker 97ffae1d30 iio: adc: xilinx: Fix VREFN sign
The VREFN channel is bipolar, not unipolar. Small negative values do
occur (e.g., -1mV), and unsigned conversion maps them incorrectly to
large positive values (about +1V), so fix this.

Signed-off-by: Thomas Betker <thomas.betker@rohde-schwarz.com>
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2015-04-19 13:49:54 +01:00
Thomas Betker 00db4e52f4 iio: adc: xilinx: Fix VREFP scale
The scaling factor for VREFP is 3.0/4096, not 1.0/4096; fix this to get
correct readings.

Signed-off-by: Thomas Betker <thomas.betker@rohde-schwarz.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2015-04-19 13:49:44 +01:00
Thomas Betker d6c96c4228 iio: adc: xilinx: Fix "vccaux" channel .address
For the "vccaux" channel, read the VCCAUX register, not VCCINT.

Signed-off-by: Thomas Betker <thomas.betker@rohde-schwarz.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2015-04-19 13:49:00 +01:00
Greg Kroah-Hartman d84a2b0d6f Merge 3.17-rc6 into staging-next.
We want the fixes in there, and it resolves a merge issue with
drivers/iio/accel/bma180.c

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-09-22 07:30:03 -07:00
Subbaraya Sundeep Bhatta 1887e724e2 iio: adc: xilinx-xadc: assign auxiliary channels address correctly
This patch fixes incorrect logic for assigning address
to auxiliary channels of xilinx xadc.

Signed-off-by: Subbaraya Sundeep Bhatta <sbhatta@xilinx.com>
Acked-by: Lars-Peter Clausen <lars@metafoo.de>
Cc: Stable@vger.kernel.org
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2014-09-14 18:18:22 +01:00
Michal Simek ff9e762158 iio: adc: xilinx: Remove .owner field for driver
There is no need to init .owner field.

Based on the patch from Peter Griffin <peter.griffin@linaro.org>
"mmc: remove .owner field for drivers using module_platform_driver"

This patch removes the superflous .owner field for drivers which
use the module_platform_driver API, as this is overriden in
platform_driver_register anyway."

Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2014-08-19 20:25:10 +01:00
Julia Lawall 889c558095 iio: fix error return code
Convert a zero return value on error to a negative one, as returned
elsewhere in the function.

A simplified version of the semantic match that finds this problem is as
follows: (http://coccinelle.lip6.fr/)

// <smpl>
(
if@p1 (\(ret < 0\|ret != 0\))
 { ... return ret; }
|
ret@p1 = 0
)
... when != ret = e1
    when != &ret
*if(...)
{
  ... when != ret = e2
      when forall
 return ret;
}

// </smpl>

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2014-08-07 10:26:53 +01:00
Peter Meerwald 398fd22b6b iio: Remove timestamp argument from iio_trigger_poll() and iio_trigger_poll_chained()
argument has been ignored; adjust drivers accordingly

Signed-off-by: Peter Meerwald <pmeerw@pmeerw.net>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2014-06-14 16:25:59 +01:00
Lars-Peter Clausen bdc8cda1d0 iio:adc: Add Xilinx XADC driver
The Xilinx XADC is a ADC that can be found in the series 7 FPGAs from Xilinx.
The XADC has a DRP interface for communication. Currently two different
frontends for the DRP interface exist. One that is only available on the ZYNQ
family as a hardmacro in the SoC portion of the ZYNQ. The other one is available
on all series 7 platforms and is a softmacro with a AXI interface. This driver
supports both interfaces and internally has a small abstraction layer that hides
the specifics of these interfaces from the main driver logic.

The ADC has a couple of internal channels which are used for voltage and
temperature monitoring of the FPGA as well as one primary and up to 16 channels
auxiliary channels for measuring external voltages. The external auxiliary
channels can either be directly connected each to one physical pin on the FPGA
or they can make use of an external multiplexer which is responsible for
multiplexing the external signals onto one pair of physical pins.

The voltage and temperature monitoring channels also have an event capability
which allows to generate a interrupt when their value falls below or raises
above a set threshold.

Buffered sampling mode is supported by the driver, but only for AXI-XADC since
the ZYNQ XADC interface does not have capabilities for supporting buffer mode
(no end-of-conversion interrupt). If buffered mode is supported the driver will
register two triggers. One "xadc-samplerate" trigger which will generate samples
with the configured samplerate. And one "xadc-convst" trigger which will
generate one sample each time the CONVST (conversion start) signal is asserted.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2014-03-01 21:04:29 +00:00