Upgrade to 4.4.50-rt62

[kvmfornfv.git] / kernel / drivers / iio / adc / ti_am335x_adc.c

diff --git a/kernel/drivers/iio/adc/ti_am335x_adc.c b/kernel/drivers/iio/adc/ti_am335x_adc.c
index c1e0553..0470fc8 100644 (file)
--- a/kernel/drivers/iio/adc/ti_am335x_adc.c
+++ b/kernel/drivers/iio/adc/ti_am335x_adc.c
@@ -32,6 +32,7 @@
 
 struct tiadc_device {
        struct ti_tscadc_dev *mfd_tscadc;
+       struct mutex fifo1_lock; /* to protect fifo access */
        int channels;
        u8 channel_line[8];
        u8 channel_step[8];
@@ -360,6 +361,7 @@ static int tiadc_read_raw(struct iio_dev *indio_dev,
                int *val, int *val2, long mask)
 {
        struct tiadc_device *adc_dev = iio_priv(indio_dev);
+       int ret = IIO_VAL_INT;
        int i, map_val;
        unsigned int fifo1count, read, stepid;
        bool found = false;
@@ -373,13 +375,14 @@ static int tiadc_read_raw(struct iio_dev *indio_dev,
        if (!step_en)
                return -EINVAL;
 
+       mutex_lock(&adc_dev->fifo1_lock);
        fifo1count = tiadc_readl(adc_dev, REG_FIFO1CNT);
        while (fifo1count--)
                tiadc_readl(adc_dev, REG_FIFO1);
 
        am335x_tsc_se_set_once(adc_dev->mfd_tscadc, step_en);
 
-       timeout = jiffies + usecs_to_jiffies
+       timeout = jiffies + msecs_to_jiffies
                                (IDLE_TIMEOUT * adc_dev->channels);
        /* Wait for Fifo threshold interrupt */
        while (1) {
@@ -389,7 +392,8 @@ static int tiadc_read_raw(struct iio_dev *indio_dev,
 
                if (time_after(jiffies, timeout)) {
                        am335x_tsc_se_adc_done(adc_dev->mfd_tscadc);
-                       return -EAGAIN;
+                       ret = -EAGAIN;
+                       goto err_unlock;
                }
        }
        map_val = adc_dev->channel_step[chan->scan_index];
@@ -415,8 +419,11 @@ static int tiadc_read_raw(struct iio_dev *indio_dev,
        am335x_tsc_se_adc_done(adc_dev->mfd_tscadc);
 
        if (found == false)
-               return -EBUSY;
-       return IIO_VAL_INT;
+               ret =  -EBUSY;
+
+err_unlock:
+       mutex_unlock(&adc_dev->fifo1_lock);
+       return ret;
 }
 
 static const struct iio_info tiadc_info = {
@@ -485,6 +492,7 @@ static int tiadc_probe(struct platform_device *pdev)
 
        tiadc_step_config(indio_dev);
        tiadc_writel(adc_dev, REG_FIFO1THR, FIFO1_THRESHOLD);
+       mutex_init(&adc_dev->fifo1_lock);
 
        err = tiadc_channel_init(indio_dev, adc_dev->channels);
        if (err < 0)