Commit 6c846d02 authored by Marc Zyngier's avatar Marc Zyngier
Browse files

gpio: Don't fiddle with irqchips marked as immutable 



In order to move away from gpiolib messing with the internals of
unsuspecting irqchips, add a flag by which irqchips advertise
that they are not to be messed with, and do solemnly swear that
they correctly call into the gpiolib helpers when required.

Also nudge the users into converting their drivers to the
new model.

Reviewed-by: default avatarAndy Shevchenko <andy.shevchenko@gmail.com>
Reviewed-by: default avatarBartosz Golaszewski <brgl@bgdev.pl>
Signed-off-by: default avatarMarc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20220419141846.598305-2-maz@kernel.org
parent 31231092

drivers/gpio/gpiolib.c

+6 −1
Original line number Diff line number Diff line
@@ -1475,6 +1475,11 @@ static void gpiochip_set_irq_hooks(struct gpio_chip *gc) 
{

	struct irq_chip *irqchip = gc->irq.chip;



	if (irqchip->flags & IRQCHIP_IMMUTABLE)

		return;



	chip_warn(gc, "not an immutable chip, please consider fixing it!\n");



	if (!irqchip->irq_request_resources &&

	    !irqchip->irq_release_resources) {

		irqchip->irq_request_resources = gpiochip_irq_reqres;
@@ -1633,7 +1638,7 @@ static void gpiochip_irqchip_remove(struct gpio_chip *gc) 
		irq_domain_remove(gc->irq.domain);

	}



	if (irqchip) {

	if (irqchip && !(irqchip->flags & IRQCHIP_IMMUTABLE)) {

		if (irqchip->irq_request_resources == gpiochip_irq_reqres) {

			irqchip->irq_request_resources = NULL;

			irqchip->irq_release_resources = NULL;

include/linux/irq.h

+2 −0
Original line number Diff line number Diff line
@@ -569,6 +569,7 @@ struct irq_chip { 
 * IRQCHIP_ENABLE_WAKEUP_ON_SUSPEND:  Invokes __enable_irq()/__disable_irq() for wake irqs

 *                                    in the suspend path if they are in disabled state

 * IRQCHIP_AFFINITY_PRE_STARTUP:      Default affinity update before startup

 * IRQCHIP_IMMUTABLE:		      Don't ever change anything in this chip

 */

enum {

	IRQCHIP_SET_TYPE_MASKED			= (1 <<  0),
@@ -582,6 +583,7 @@ enum { 
	IRQCHIP_SUPPORTS_NMI			= (1 <<  8),

	IRQCHIP_ENABLE_WAKEUP_ON_SUSPEND	= (1 <<  9),

	IRQCHIP_AFFINITY_PRE_STARTUP		= (1 << 10),

	IRQCHIP_IMMUTABLE			= (1 << 11),

};



#include <linux/irqdesc.h>

kernel/irq/debugfs.c

+1 −0
Original line number Diff line number Diff line
@@ -58,6 +58,7 @@ static const struct irq_bit_descr irqchip_flags[] = { 
	BIT_MASK_DESCR(IRQCHIP_SUPPORTS_LEVEL_MSI),

	BIT_MASK_DESCR(IRQCHIP_SUPPORTS_NMI),

	BIT_MASK_DESCR(IRQCHIP_ENABLE_WAKEUP_ON_SUSPEND),

	BIT_MASK_DESCR(IRQCHIP_IMMUTABLE),

};



static void