It has two main use cases:
1) Allow drivers to reset their hardware via a GPIO line in a standard fashion
as supplied by the reset framework.
This allows adhoc driver code requesting GPIOs etc to be replaced with a
single call to device_reset().
2) Allow hardware on discoverable busses to be rest via a GPIO line
without driver modifications.
Examples of the second use case include:
* SDIO wifi modules
* USB hub chips with a reset line
In this second use case the reset has to be done externally to the driver
managing the hardware since resetting the device from the driver's probe()
method will either do nothing (if the device needs to be reset before
ennumeration will work) or cause racy beahviour (when the device disappears
from the bus during probe()).
So, in addition to providing a gpio based reset controller implementation
it is also possible to reset devices at boot via a DT property or from
userspace on request via sysfs attributes.
Change-Id: I316f9e622d99cff7167b57e8fd5ff73a34dc2a81
Signed-off-by: Martin Fuzzey <mfuzzey@parkeon.com>
Signed-off-by: Kevin Kim <ckkim@hardkernel.com>
[ Upstream commit 3cba9cfcc1520a2307a29f6fab887bcfc121c417 ]
If the device is unplugged and CONFIG_IIO is not supported, this will
result in a warning message at kernel/workqueue.
Only cancel delayed work in mcp2221_remove(), when CONFIG_IIO is enabled.
Signed-off-by: Abdelrahman Morsy <abdelrahmanhesham94@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Change-Id: I583aa986bcc453cc351ba8f2ec8e1972a365282a
[ Upstream commit 73ce9f1f2741a38f5d27393e627702ae2c46e6f2 ]
During the probe we add an I2C adapter and as soon as we add that adapter
it may be used for a transfer (e.g via the code in i2cdetect()).
Those transfers are not able to complete and time out. This is because the
HID raw_event callback (mcp2221_raw_event) will not be invoked until the
HID device's 'driver_input_lock' is marked up at the completion of the
probe in hid_device_probe(). This starves the driver of the responses it
is waiting for.
In order to allow the I2C transfers to complete while we are still in the
probe, start the IO once we have completed init of the HID device.
This issue seems to have been seen before and a patch was submitted but
it seems it was never accepted. See:
https://lore.kernel.org/all/20221103222714.21566-3-Enrik.Berkhan@inka.de/
Signed-off-by: Hamish Martin <hamish.martin@alliedtelesis.co.nz>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Change-Id: I250bb6b5c7432ddb008cd9feb4975c2502b98390
[ Upstream commit f2d4a5834638bbc967371b9168c0b481519f7c5e ]
The process of adding an I2C adapter can invoke I2C accesses on that new
adapter (see i2c_detect()).
Ensure we have set the adapter's driver data to avoid null pointer
dereferences in the xfer functions during the adapter add.
This has been noted in the past and the same fix proposed but not
completed. See:
https://lore.kernel.org/lkml/ef597e73-ed71-168e-52af-0d19b03734ac@vigem.de/
Signed-off-by: Hamish Martin <hamish.martin@alliedtelesis.co.nz>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Change-Id: I5a72d1c59d884748f73a434a02d314963c77568b
The mcp2221_raw_event retrieves the value and direction of gpio on the
same command, by setting the value on mcp->status and the direction on
mcp->gpio_dir; and the offset at which they are read is based on
mcp->gp_idx, set by the gpiochip callbacks.
However, the individual gpiochip calls set the index to look for
directly on the field they want to track. This create a "double offset"
in the final read in the response report.
Align the behaviour of mcp2221_raw_event and
mcp_gpio_get/mcp_gpio_get_direction by putting gp_idx on those calls to
the base offset of the gpio status struct.
Signed-off-by: Louis Morhet <lmorhet@kalrayinc.com>
Link: https://lore.kernel.org/r/dd0b23800a79d2a464e1e9ed429b018b69fd5df2.1680602387.git.lmorhet@kalrayinc.com
Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Change-Id: I47c3d3d3c0ad7b7072614fefa9e804d417be8bba
The documentation of the component (section 3.1.12 GET GPIO VALUES)
describes the hid report structure with two fields per gpio:
its value, followed by its direction.
However, the driver describes it with a wrong order:
direction followed by value.
Fix the structure representing the report answered by the chip to the
GET GPIO VALUES command.
Fixes commit 567b8e9fed ("HID: mcp2221: Fix GPIO output handling")
Signed-off-by: Louis Morhet <lmorhet@kalrayinc.com>
Link: https://lore.kernel.org/r/945967fbab56d53f9630ad3844b64734f8c3107e.1680602387.git.lmorhet@kalrayinc.com
Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Change-Id: I21d45bb9d4a4957c37b5e27cf67d3c8045f9b035
If the device is plugged/unplugged without giving time for mcp_init_work()
to complete, we might kick in the devm free code path and thus have
unavailable struct mcp_2221 while in delayed work.
Canceling the delayed_work item is enough to solve the issue, because
cancel_delayed_work_sync will prevent the work item to requeue itself.
Fixes: 960f9df7c6 ("HID: mcp2221: add ADC/DAC support via iio subsystem")
CC: stable@vger.kernel.org
Acked-by: Jiri Kosina <jkosina@suse.cz>
Link: https://lore.kernel.org/r/20230215-wip-mcp2221-v2-1-109f71fd036e@redhat.com
Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Change-Id: I35ca79b8a7b96dc72c702af8ea79d4c5ca92935f
Singular #ifdef IS_REACHABLE(CONFIG_GPIOLIB) weren't covering all the
gpiolib functions that were being referenced.
Update the code regions that are commented out when CONFIG_GPIOLIB isn't
enabled to avoid errors.
Fixes: 960f9df7c6 ("HID: mcp2221: add ADC/DAC support via iio subsystem")
Signed-off-by: Matt Ranostay <matt.ranostay@konsulko.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Change-Id: I0b786ac507f9eff0dd589d4a547ce3f1ff425b78
Use (__force __le16) cast for adc_values le16_to_cpu conversion to correct following sparse
warnings:
drivers/hid/hid-mcp2221.c:950:32: sparse: sparse: cast to restricted __le16
Reported-by: kernel test robot <lkp@intel.com>
Fixes: 960f9df7c6 ("HID: mcp2221: add ADC/DAC support via iio subsystem")
Signed-off-by: Matt Ranostay <matt.ranostay@konsulko.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Change-Id: If0a7a009669f6458c45089483179238525114e48
In mcp2221_raw_event(), 'tmp' is used only conditionally. Move
the declaration into the conditional block in order to prevent
unused variable warning.
Reported-by: kernel test robot <lkp@intel.com>
Fixes: 960f9df7c6 ("HID: mcp2221: add ADC/DAC support via iio subsystem")
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Change-Id: Icb349aaa2fdcfc48d975be4124532f53f894768a
Add support for 3x 10-bit ADC and 1x DAC channels registered via the iio
subsystem.
To prevent breakage and unexpected dependencies this support only is
only built if CONFIG_IIO is enabled, and is only weakly referenced by
'imply IIO' within the respective Kconfig.
Additionally the iio device only gets registered if at least one channel
is enabled in the power-on configuration read from SRAM.
Signed-off-by: Matt Ranostay <matt.ranostay@konsulko.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Change-Id: I898368e779dcced15b12d43f88a38f71a31be80f
To avoid recursive dependencies on GPIOLIB when 'imply IIO' is requested
with other drivers we should switch GPIOLIB to an imply.
This isn't the most ideal solution but avoids modifiying the Kconfig for
other drivers, and only requires a singular IS_REACHABLE(CONFIG_GPIOLIB)
check.
Signed-off-by: Matt Ranostay <matt.ranostay@konsulko.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Change-Id: Ie379ae18bd2aae09b576238298715055ca616f0d
Switch from i2c_add_adapter() to resource managed devm_i2c_add_adapter()
for matching rest of driver initialization, and more concise code.
Signed-off-by: Matt Ranostay <matt.ranostay@konsulko.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Change-Id: I642fcb5af3894a2010b4a8f2f06098abaecf6812
SoC level driver bugs to manage kernel binaries as well as import them
to initramfs to make them load very early, this could cause boot failure
when one fails to update initramfs. So such driver must be in kernel
blob itself, not to miss.
Signed-off-by: Dongjin Kim <tobetter@gmail.com>
Change-Id: Iea67d3fa3a97146db47cae25b2a7d5eb5b938f5c
