Commit 9517d76d authored by Haotian Zhang's avatar Haotian Zhang Committed by William Breathitt Gray
Browse files

counter: 104-quad-8: Fix incorrect return value in IRQ handler 



quad8_irq_handler() should return irqreturn_t enum values, but it
directly returns negative errno codes from regmap operations on error.

Return IRQ_NONE if the interrupt status cannot be read. If clearing the
interrupt fails, return IRQ_HANDLED to prevent the kernel from disabling
the IRQ line due to a spurious interrupt storm. Also, log these regmap
failures with dev_WARN_ONCE.

Fixes: 98ffe025 ("counter: 104-quad-8: Migrate to the regmap API")
Suggested-by: default avatarAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: default avatarHaotian Zhang <vulab@iscas.ac.cn>
Link: https://lore.kernel.org/r/20251215020114.1913-1-vulab@iscas.ac.cn


Cc: stable@vger.kernel.org
Signed-off-by: default avatarWilliam Breathitt Gray <wbg@kernel.org>
parent 23f94855

drivers/counter/104-quad-8.c

+14 −6
Original line number Diff line number Diff line
@@ -1192,6 +1192,7 @@ static irqreturn_t quad8_irq_handler(int irq, void *private) 
{

	struct counter_device *counter = private;

	struct quad8 *const priv = counter_priv(counter);

	struct device *dev = counter->parent;

	unsigned int status;

	unsigned long irq_status;

	unsigned long channel;
@@ -1200,8 +1201,11 @@ static irqreturn_t quad8_irq_handler(int irq, void *private) 
	int ret;



	ret = regmap_read(priv->map, QUAD8_INTERRUPT_STATUS, &status);

	if (ret)

		return ret;

	if (ret) {

		dev_WARN_ONCE(dev, true,

			"Attempt to read Interrupt Status Register failed: %d\n", ret);

		return IRQ_NONE;

	}

	if (!status)

		return IRQ_NONE;
@@ -1223,7 +1227,8 @@ static irqreturn_t quad8_irq_handler(int irq, void *private) 
				break;

		default:

			/* should never reach this path */

			WARN_ONCE(true, "invalid interrupt trigger function %u configured for channel %lu\n",

			dev_WARN_ONCE(dev, true,

				"invalid interrupt trigger function %u configured for channel %lu\n",

				flg_pins, channel);

			continue;

		}
@@ -1232,8 +1237,11 @@ static irqreturn_t quad8_irq_handler(int irq, void *private) 
	}



	ret = regmap_write(priv->map, QUAD8_CHANNEL_OPERATION, CLEAR_PENDING_INTERRUPTS);

	if (ret)

		return ret;

	if (ret) {

		dev_WARN_ONCE(dev, true,

			"Attempt to clear pending interrupts by writing to Channel Operation Register failed: %d\n", ret);

		return IRQ_HANDLED;

	}



	return IRQ_HANDLED;

}