Re: [PATCH v3 4/5] iio: light: vcnl4000: Add IRQ disable callback on cleanup

[Andy Shevchenko <andriy.shevchenko@intel.com>]

On Thu, Sep 03, 2026 at 02:53:49PM +1000, Tsz Shan Chan wrote:
> During driver unbind, devm cleans up resources in LIFO order. The IRQ
> handler is freed before the device is powered down. This can lead to
> unhandled interrupts.
> 
> Register a devm action to disable interrupt explicitly after
> devm_request_threaded_irq(), so that the interrupt is disabled before
> the IRQ handler is freed. This prevents any unhandled interrupts.
> 
> Add a disable_irq callback to chip info structure. This allows each chip
> type to implement its own disable sequence.

...

> +static int vcnl4010_disable_irq(struct vcnl4000_data *data)
> +{
> +	int ret;
> +
> +	guard(mutex)(&data->vcnl4000_lock);
> +
> +	ret = vcnl4010_stop(data);
> +	if (ret < 0)
> +		return ret;
> +
> +	ret = i2c_smbus_read_byte_data(data->client, VCNL4010_ISR);
> +	if (ret < 0)
> +		return ret;

> +	ret &= VCNL4010_INT_THR | VCNL4010_INT_DRDY;
> +	if (!ret)
> +		return 0;
> +
> +	return i2c_smbus_write_byte_data(data->client, VCNL4010_ISR, ret);

Since ret is in use it's better to follow regular pattern

	ret &= VCNL4010_INT_THR | VCNL4010_INT_DRDY;
	if (ret)
		return i2c_smbus_write_byte_data(data->client, VCNL4010_ISR, ret);

	return 0;

BUT, since ret doesn't care an error code at this point, it's even better to
use proper typing.

	u8 byte;
	...

	byte = ret & (VCNL4010_INT_THR | VCNL4010_INT_DRDY);
	if (!byte)
		return 0;

	return i2c_smbus_write_byte_data(data->client, VCNL4010_ISR, byte);

> +}

-- 
With Best Regards,
Andy Shevchenko