From 557e585c3fdba1f6cddb4516a82da53b52fd9963 Mon Sep 17 00:00:00 2001 From: Stefan Popa Date: Thu, 13 Dec 2018 14:46:15 +0200 Subject: [PATCH] staging: iio: adc: ad7606: Use wait-for-completion handler This patch replaces the use of wait_event_interruptible() with wait_for_completion_timeout() when reading the result of a single conversion. In this way, if the interrupt never occurs, the program will not remain blocked. Signed-off-by: Stefan Popa Signed-off-by: Jonathan Cameron --- drivers/staging/iio/adc/ad7606.c | 14 +++++++------- drivers/staging/iio/adc/ad7606.h | 6 ++---- 2 files changed, 9 insertions(+), 11 deletions(-) diff --git a/drivers/staging/iio/adc/ad7606.c b/drivers/staging/iio/adc/ad7606.c index 7308fa8fbb4c..379a99ed22af 100644 --- a/drivers/staging/iio/adc/ad7606.c +++ b/drivers/staging/iio/adc/ad7606.c @@ -119,12 +119,13 @@ static int ad7606_scan_direct(struct iio_dev *indio_dev, unsigned int ch) struct ad7606_state *st = iio_priv(indio_dev); int ret; - st->done = false; gpiod_set_value(st->gpio_convst, 1); - - ret = wait_event_interruptible(st->wq_data_avail, st->done); - if (ret) + ret = wait_for_completion_timeout(&st->completion, + msecs_to_jiffies(1000)); + if (!ret) { + ret = -ETIMEDOUT; goto error_ret; + } ret = ad7606_read_samples(st); if (ret == 0) @@ -389,8 +390,7 @@ static irqreturn_t ad7606_interrupt(int irq, void *dev_id) if (iio_buffer_enabled(indio_dev)) { schedule_work(&st->poll_work); } else { - st->done = true; - wake_up_interruptible(&st->wq_data_avail); + complete(&st->completion); } return IRQ_HANDLED; @@ -474,7 +474,7 @@ int ad7606_probe(struct device *dev, int irq, void __iomem *base_address, indio_dev->channels = st->chip_info->channels; indio_dev->num_channels = st->chip_info->num_channels; - init_waitqueue_head(&st->wq_data_avail); + init_completion(&st->completion); ret = ad7606_reset(st); if (ret) diff --git a/drivers/staging/iio/adc/ad7606.h b/drivers/staging/iio/adc/ad7606.h index 86188054b60b..a46843f96e0c 100644 --- a/drivers/staging/iio/adc/ad7606.h +++ b/drivers/staging/iio/adc/ad7606.h @@ -29,11 +29,9 @@ struct ad7606_chip_info { * @reg regulator info for the the power supply of the device * @poll_work work struct for continuously reading data from the device * into an IIO triggered buffer - * @wq_data_avail wait queue struct for buffer mode * @bops bus operations (SPI or parallel) * @range voltage range selection, selects which scale to apply * @oversampling oversampling selection - * @done marks whether reading data is done * @base_address address from where to read data in parallel operation * @lock protect sensor state from concurrent accesses to GPIOs * @gpio_convst GPIO descriptor for conversion start signal (CONVST) @@ -44,6 +42,7 @@ struct ad7606_chip_info { * @gpio_frstdata GPIO descriptor for reading from device when data * is being read on the first channel * @gpio_os GPIO descriptors to control oversampling on the device + * @complete completion to indicate end of conversion * @data buffer for reading data from the device */ @@ -52,11 +51,9 @@ struct ad7606_state { const struct ad7606_chip_info *chip_info; struct regulator *reg; struct work_struct poll_work; - wait_queue_head_t wq_data_avail; const struct ad7606_bus_ops *bops; unsigned int range; unsigned int oversampling; - bool done; void __iomem *base_address; struct mutex lock; /* protect sensor state */ @@ -66,6 +63,7 @@ struct ad7606_state { struct gpio_desc *gpio_standby; struct gpio_desc *gpio_frstdata; struct gpio_descs *gpio_os; + struct completion completion; /* * DMA (thus cache coherency maintenance) requires the -- 2.30.2