This is a note to let you know that I've just added the patch titled
gpio: Allow per-parent interrupt data
to the 5.15-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
gpio-allow-per-parent-interrupt-data.patch
and it can be found in the queue-5.15 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 1c36d1b70503fc3e139b5edcbab6a41b665b3897
Author: Marc Zyngier <maz@xxxxxxxxxx>
Date: Tue Oct 26 18:58:11 2021 +0100
gpio: Allow per-parent interrupt data
[ Upstream commit cfe6807d82e97e81c3209dca9448f091e1448a57 ]
The core gpiolib code is able to deal with multiple interrupt parents
for a single gpio irqchip. It however only allows a single piece
of data to be conveyed to all flow handlers (either the gpio_chip
or some other, driver-specific data).
This means that drivers have to go through some interesting dance
to find the correct context, something that isn't great in interrupt
context (see aebdc8abc9db86e2bd33070fc2f961012fff74b4 for a prime
example).
Instead, offer an optional way for a pinctrl/gpio driver to provide
an array of pointers which gets used to provide the correct context
to the flow handler.
Signed-off-by: Marc Zyngier <maz@xxxxxxxxxx>
Signed-off-by: Joey Gouly <joey.gouly@xxxxxxx>
Reviewed-by: Linus Walleij <linus.walleij@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20211026175815.52703-2-joey.gouly@xxxxxxx
Signed-off-by: Linus Walleij <linus.walleij@xxxxxxxxxx>
Stable-dep-of: 8c00914e5438 ("gpiolib: Fix GPIO chip IRQ initialization restriction")
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
index 8c041a8dd9d8f..099fe2e39bd63 100644
--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -1578,9 +1578,14 @@ static int gpiochip_add_irqchip(struct gpio_chip *gc,
}
if (gc->irq.parent_handler) {
- void *data = gc->irq.parent_handler_data ?: gc;
-
for (i = 0; i < gc->irq.num_parents; i++) {
+ void *data;
+
+ if (gc->irq.per_parent_data)
+ data = gc->irq.parent_handler_data_array[i];
+ else
+ data = gc->irq.parent_handler_data ?: gc;
+
/*
* The parent IRQ chip is already using the chip_data
* for this IRQ chip, so our callbacks simply use the
diff --git a/include/linux/gpio/driver.h b/include/linux/gpio/driver.h
index 11c26ae7b4fa4..65df2ce96f0b1 100644
--- a/include/linux/gpio/driver.h
+++ b/include/linux/gpio/driver.h
@@ -168,11 +168,18 @@ struct gpio_irq_chip {
/**
* @parent_handler_data:
+ * @parent_handler_data_array:
*
* Data associated, and passed to, the handler for the parent
- * interrupt.
+ * interrupt. Can either be a single pointer if @per_parent_data
+ * is false, or an array of @num_parents pointers otherwise. If
+ * @per_parent_data is true, @parent_handler_data_array cannot be
+ * NULL.
*/
- void *parent_handler_data;
+ union {
+ void *parent_handler_data;
+ void **parent_handler_data_array;
+ };
/**
* @num_parents:
@@ -203,6 +210,14 @@ struct gpio_irq_chip {
*/
bool threaded;
+ /**
+ * @per_parent_data:
+ *
+ * True if parent_handler_data_array describes a @num_parents
+ * sized array to be used as parent data.
+ */
+ bool per_parent_data;
+
/**
* @init_hw: optional routine to initialize hardware before
* an IRQ chip will be added. This is quite useful when
