As a way to allow the user-space to stop referring to GPIOs by their
global numbers, introduce a parallel group of line attributes for
exported GPIO that live inside the GPIO chip class device and are
referred to by their HW offset within their parent chip.
Reviewed-by: Linus Walleij <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Bartosz Golaszewski <[email protected]>
In preparation for adding a parallel, per-chip attribute group for
exported GPIO lines, stop using class device APIs to refer to it in the
code. When unregistering the chip, don't call class_find_device() but
instead store exported lines in a linked list inside the GPIO chip data
object and look it up there.
Reviewed-by: Linus Walleij <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Bartosz Golaszewski <[email protected]>
Currently each exported GPIO is represented in sysfs as a separate class
device. This allows us to simply use dev_get_drvdata() to retrieve the
pointer passed to device_create_with_groups() from sysfs ops callbacks.
However, we're preparing to add a parallel set of per-line sysfs
attributes that will live inside the associated gpiochip group. They are
not registered as class devices and so have the parent device passed as
argument to their callbacks (the GPIO chip class device).
Put the attribute structs inside the GPIO descriptor data and
dereference the relevant ones using container_of() in the callbacks.
This way, we'll be able to reuse the same code for both the legacy and
new GPIO attributes.
Reviewed-by: Linus Walleij <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Bartosz Golaszewski <[email protected]>
In preparation for future commits which will make use of descriptor AND
GPIO-device data in the same functions rename the former from data to
desc_data separately which will make future changes smaller and easier
to read.
Reviewed-by: Linus Walleij <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Bartosz Golaszewski <[email protected]>
We don't use any fields from struct device in gpio_sysfs_request_irq(),
gpio_sysfs_free_irq() and gpio_sysfs_set_active_low(). We only use the
dev argument to get the associated struct gpiod_data pointer with
dev_get_drvdata().
To make the transition to not using dev_get_drvdata() across line
callbacks for sysfs attributes easier, pass gpiod_data directly to
these functions instead of having it wrapped in struct device.
Reviewed-by: Linus Walleij <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Bartosz Golaszewski <[email protected]>
In order to enable moving away from the global GPIO numberspace-based
exporting of lines over sysfs: add a parallel, per-chip entry under
/sys/class/gpio/ for every registered GPIO chip, denoted by device ID
in the file name and not its base GPIO number.
Compared to the existing chip group: it does not contain the "base"
attribute as the goal of this change is to not refer to GPIOs by their
global number from user-space anymore. It also contains its own,
per-chip export/unexport attribute pair which allow to export lines by
their hardware offset within the chip.
Caveat #1: the new device cannot be a link to (or be linked to by) the
existing "gpiochip<BASE>" entry as we cannot create links in
/sys/class/xyz/.
Caveat #2: the new entry cannot be named "gpiochipX" as it could
conflict with devices whose base is statically defined to a low number.
Let's go with "chipX" instead.
While at it: the chip label is unique so update the untrue statement
when extending the docs.
Acked-by: Linus Walleij <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Bartosz Golaszewski <[email protected]>
We have a dedicated comparator for GPIO descriptors that performs
additional checks and hides the implementation detail of whether the
same GPIO can be associated with two separate struct gpio_desc objects.
Use it in sysfs code
Reviewed-by: Linus Walleij <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Bartosz Golaszewski <[email protected]>
Using regmap_update_bits() allows to reduce the number of I2C transfers
when updating bits that haven't changed on non-volatile registers.
For example on a PCAL6416, when changing a GPIO direction from input to
output, the number of I2C transfers can be reduced from 4 to just 1 if
the pull resistors configuration hasn't changed and the output value
is the same as before.
Signed-off-by: Hugo Villeneuve <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Bartosz Golaszewski <[email protected]>
One of the users of global GPIO numbers in the kernel are the debugfs
callbacks in GPIO drivers. Before converting any custom .dbg_show()
callbacks in individual modules, let's first make GPIO core stop using
GPIO base in debugfs output. Use hardware offsets instead.
Reviewed-by: Linus Walleij <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Bartosz Golaszewski <[email protected]>
Add a new line-level, boolean property to the gpio-sim configfs
interface called 'valid'. It's set by default and the user can unset it
to make the line be included in the standard `gpio-reserved-ranges`
property when the chip is registered with GPIO core. This allows users
to specify which lines should not be available for requesting as GPIOs.
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Bartosz Golaszewski <[email protected]>
The TI TCA6418 is a 18-channel I2C I/O expander. It is slightly
different to other models from the same family, such as TCA6416,
but has enough in common with them to make it work with just a
few tweaks, which are explained in the code's documentation.
Signed-off-by: Maria Garcia <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Bartosz Golaszewski <[email protected]>
pm_runtime_put_autosuspend(), pm_runtime_put_sync_autosuspend(),
pm_runtime_autosuspend() and pm_request_autosuspend() now include a call
to pm_runtime_mark_last_busy(). Remove the now-reduntant explicit call to
pm_runtime_mark_last_busy().
Reviewed-by: Charles Keepax <[email protected]>
Signed-off-by: Sakari Ailus <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Bartosz Golaszewski <[email protected]>
Runtime PM updates related to autosuspend for 6.17
Make several autosuspend functions mark last busy stamp and update
the documentation accordingly (Sakari Ailus).
Bartosz Golaszewski