From be2ea53330f1865ac5b00377f2074f8e255bf74c Mon Sep 17 00:00:00 2001 From: Quentin Schulz Date: Mon, 3 Jul 2017 15:09:26 +0200 Subject: [PATCH] iio: adc: sun4i-gpadc-iio: fix unbalanced irq enable/disable MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit When initializing interrupts, the devm_request_any_context_irq will enable them right away. An atomic flag was set in sun4i_irq_init and read in the interrupt handler to make sure no unwanted interrupts were handled. If an unwanted interrupt occurred, the handler would disable the irq and return IRQ_HANDLED. However, at the end of sun4i_irq_init, the irq would be disabled as well, resulting in an unbalanced enable (since there are more disables than enables, the code enabling the interrupt would never be called). When reading the ADC or the temperature, the respective irq would be enabled in the read function and disabled in the irq handler. In the read function, we would wait for a completion (with a timeout) that will be set in the irq handler. However, if the completion is never set or if the wait for completion times out, the irq would not be disabled in the read function resulting in an unbalanced enable once the read function is called again (since there are 2+ enables for no disable). Moving disable_irq from the irq handler to the read function get rid of these two cases of unbalanced enable. Fixes: d1caa9905538 ("iio: adc: add support for Allwinner SoCs ADC") Reported-by: Andreas Färber Signed-off-by: Quentin Schulz Acked-by: Maxime Ripard Signed-off-by: Jonathan Cameron --- drivers/iio/adc/sun4i-gpadc-iio.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/drivers/iio/adc/sun4i-gpadc-iio.c b/drivers/iio/adc/sun4i-gpadc-iio.c index 81d4c39e414a..137f577d9432 100644 --- a/drivers/iio/adc/sun4i-gpadc-iio.c +++ b/drivers/iio/adc/sun4i-gpadc-iio.c @@ -256,6 +256,7 @@ static int sun4i_gpadc_read(struct iio_dev *indio_dev, int channel, int *val, err: pm_runtime_put_autosuspend(indio_dev->dev.parent); + disable_irq(irq); mutex_unlock(&info->mutex); return ret; @@ -365,7 +366,6 @@ static irqreturn_t sun4i_gpadc_temp_data_irq_handler(int irq, void *dev_id) complete(&info->completion); out: - disable_irq_nosync(info->temp_data_irq); return IRQ_HANDLED; } @@ -380,7 +380,6 @@ static irqreturn_t sun4i_gpadc_fifo_data_irq_handler(int irq, void *dev_id) complete(&info->completion); out: - disable_irq_nosync(info->fifo_data_irq); return IRQ_HANDLED; } -- 2.30.2