genirq/generic_chip: Make irq_remove_generic_chip() irqdomain aware

irq_remove_generic_chip() calculates the Linux interrupt number for removing the
handler and interrupt chip based on gc::irq_base as a linear function of
the bit positions of set bits in the @msk argument.

When the generic chip is present in an irq domain, i.e. created with a call
to irq_alloc_domain_generic_chips(), gc::irq_base contains not the base
Linux interrupt number.  It contains the base hardware interrupt for this
chip. It is set to 0 for the first chip in the domain, 0 + N for the next
chip, where $N is the number of hardware interrupts per chip.

That means the Linux interrupt number cannot be calculated based on
gc::irq_base for irqdomain based chips without a domain map lookup, which
is currently missing.

Rework the code to take the irqdomain case into account and calculate the
Linux interrupt number by a irqdomain lookup of the domain specific
hardware interrupt number.

[ tglx: Massage changelog. Reshuffle the logic and add a proper comment. ]

Fixes: cfefd21e693d ("genirq: Add chip suspend and resume callbacks")
Signed-off-by: Herve Codina <herve.codina@bootlin.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20231024150335.322282-1-herve.codina@bootlin.com

diff --git a/kernel/irq/generic-chip.c b/kernel/irq/generic-chip.c
index 81ecca08caad11ad5b9c6e032273bd5545f39cef..d39a40bc542bae4b9bcec78eba8ed9bc3f1d71ca 100644 (file)
--- a/kernel/irq/generic-chip.c
+++ b/kernel/irq/generic-chip.c
@@ -548,21 +548,34 @@ EXPORT_SYMBOL_GPL(irq_setup_alt_chip);
 void irq_remove_generic_chip(struct irq_chip_generic *gc, u32 msk,
                             unsigned int clr, unsigned int set)
 {
-       unsigned int i = gc->irq_base;
+       unsigned int i, virq;
 
        raw_spin_lock(&gc_lock);
        list_del(&gc->list);
        raw_spin_unlock(&gc_lock);
 
-       for (; msk; msk >>= 1, i++) {
+       for (i = 0; msk; msk >>= 1, i++) {
                if (!(msk & 0x01))
                        continue;
 
+               /*
+                * Interrupt domain based chips store the base hardware
+                * interrupt number in gc::irq_base. Otherwise gc::irq_base
+                * contains the base Linux interrupt number.
+                */
+               if (gc->domain) {
+                       virq = irq_find_mapping(gc->domain, gc->irq_base + i);
+                       if (!virq)
+                               continue;
+               } else {
+                       virq = gc->irq_base + i;
+               }
+
                /* Remove handler first. That will mask the irq line */
-               irq_set_handler(i, NULL);
-               irq_set_chip(i, &no_irq_chip);
-               irq_set_chip_data(i, NULL);
-               irq_modify_status(i, clr, set);
+               irq_set_handler(virq, NULL);
+               irq_set_chip(virq, &no_irq_chip);
+               irq_set_chip_data(virq, NULL);
+               irq_modify_status(virq, clr, set);
        }
 }
 EXPORT_SYMBOL_GPL(irq_remove_generic_chip);