gpio: pca953x: Add support for level-triggered interrupts

Adds support for level-triggered interrupts in the PCA953x GPIO
expander driver. Previously, the driver only supported edge-triggered
interrupts, which could lead to missed events in scenarios where an
interrupt condition persists until it is explicitly cleared.

By enabling level-triggered interrupts, the driver can now detect and
respond to sustained interrupt conditions more reliably.

Signed-off-by: Potin Lai <potin.lai.pt@gmail.com>
Link: https://lore.kernel.org/r/20250409-gpio-pca953x-level-triggered-irq-v3-1-7f184d814934@gmail.com
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
This commit is contained in:
Potin Lai 2025-04-09 23:37:30 +08:00 committed by Bartosz Golaszewski
parent 73dc041f8a
commit 417b0f8d08

View File

@ -215,6 +215,8 @@ struct pca953x_chip {
DECLARE_BITMAP(irq_stat, MAX_LINE);
DECLARE_BITMAP(irq_trig_raise, MAX_LINE);
DECLARE_BITMAP(irq_trig_fall, MAX_LINE);
DECLARE_BITMAP(irq_trig_level_high, MAX_LINE);
DECLARE_BITMAP(irq_trig_level_low, MAX_LINE);
#endif
atomic_t wakeup_path;
@ -774,6 +776,8 @@ static void pca953x_irq_bus_sync_unlock(struct irq_data *d)
pca953x_read_regs(chip, chip->regs->direction, reg_direction);
bitmap_or(irq_mask, chip->irq_trig_fall, chip->irq_trig_raise, gc->ngpio);
bitmap_or(irq_mask, irq_mask, chip->irq_trig_level_high, gc->ngpio);
bitmap_or(irq_mask, irq_mask, chip->irq_trig_level_low, gc->ngpio);
bitmap_complement(reg_direction, reg_direction, gc->ngpio);
bitmap_and(irq_mask, irq_mask, reg_direction, gc->ngpio);
@ -791,13 +795,15 @@ static int pca953x_irq_set_type(struct irq_data *d, unsigned int type)
struct device *dev = &chip->client->dev;
irq_hw_number_t hwirq = irqd_to_hwirq(d);
if (!(type & IRQ_TYPE_EDGE_BOTH)) {
if (!(type & IRQ_TYPE_SENSE_MASK)) {
dev_err(dev, "irq %d: unsupported type %d\n", d->irq, type);
return -EINVAL;
}
assign_bit(hwirq, chip->irq_trig_fall, type & IRQ_TYPE_EDGE_FALLING);
assign_bit(hwirq, chip->irq_trig_raise, type & IRQ_TYPE_EDGE_RISING);
assign_bit(hwirq, chip->irq_trig_level_low, type & IRQ_TYPE_LEVEL_LOW);
assign_bit(hwirq, chip->irq_trig_level_high, type & IRQ_TYPE_LEVEL_HIGH);
return 0;
}
@ -810,6 +816,8 @@ static void pca953x_irq_shutdown(struct irq_data *d)
clear_bit(hwirq, chip->irq_trig_raise);
clear_bit(hwirq, chip->irq_trig_fall);
clear_bit(hwirq, chip->irq_trig_level_low);
clear_bit(hwirq, chip->irq_trig_level_high);
}
static void pca953x_irq_print_chip(struct irq_data *data, struct seq_file *p)
@ -840,6 +848,7 @@ static bool pca953x_irq_pending(struct pca953x_chip *chip, unsigned long *pendin
DECLARE_BITMAP(cur_stat, MAX_LINE);
DECLARE_BITMAP(new_stat, MAX_LINE);
DECLARE_BITMAP(trigger, MAX_LINE);
DECLARE_BITMAP(edges, MAX_LINE);
int ret;
ret = pca953x_read_regs(chip, chip->regs->input, cur_stat);
@ -857,13 +866,26 @@ static bool pca953x_irq_pending(struct pca953x_chip *chip, unsigned long *pendin
bitmap_copy(chip->irq_stat, new_stat, gc->ngpio);
if (bitmap_empty(trigger, gc->ngpio))
return false;
if (bitmap_empty(chip->irq_trig_level_high, gc->ngpio) &&
bitmap_empty(chip->irq_trig_level_low, gc->ngpio)) {
if (bitmap_empty(trigger, gc->ngpio))
return false;
}
bitmap_and(cur_stat, chip->irq_trig_fall, old_stat, gc->ngpio);
bitmap_and(old_stat, chip->irq_trig_raise, new_stat, gc->ngpio);
bitmap_or(new_stat, old_stat, cur_stat, gc->ngpio);
bitmap_and(pending, new_stat, trigger, gc->ngpio);
bitmap_or(edges, old_stat, cur_stat, gc->ngpio);
bitmap_and(pending, edges, trigger, gc->ngpio);
bitmap_and(cur_stat, new_stat, chip->irq_trig_level_high, gc->ngpio);
bitmap_and(cur_stat, cur_stat, chip->irq_mask, gc->ngpio);
bitmap_or(pending, pending, cur_stat, gc->ngpio);
bitmap_complement(cur_stat, new_stat, gc->ngpio);
bitmap_and(cur_stat, cur_stat, reg_direction, gc->ngpio);
bitmap_and(old_stat, cur_stat, chip->irq_trig_level_low, gc->ngpio);
bitmap_and(old_stat, old_stat, chip->irq_mask, gc->ngpio);
bitmap_or(pending, pending, old_stat, gc->ngpio);
return !bitmap_empty(pending, gc->ngpio);
}