staging: iio: adc: palmas: add debug prints when ADC failed.

Prints the ADC status and irq status when ADC conversion failed
with timeout. This helps on debugging the issue when such failure
occurs.

bug 1527322

Change-Id: Idc09f1d074f113941b6190f36060ebbfb7eed172
Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
Reviewed-on: http://git-master/r/428896

diff --git a/drivers/staging/iio/adc/palmas_gpadc.c b/drivers/staging/iio/adc/palmas_gpadc.c
index f726f483d7094fd5016c52b9f254631d083325aa..c99bc5ea5865b15e2b063c1d17773e1b49a4956a 100644 (file)
--- a/drivers/staging/iio/adc/palmas_gpadc.c
+++ b/drivers/staging/iio/adc/palmas_gpadc.c
@@ -106,6 +106,7 @@ struct palmas_gpadc {
        struct dentry                   *dentry;
        bool is_shutdown;
        struct mutex lock;
+       bool isr_done;
 };
 
 /*
@@ -167,6 +168,7 @@ static irqreturn_t palmas_gpadc_irq(int irq, void *data)
 {
        struct palmas_gpadc *adc = data;
 
+       adc->isr_done = true;
        complete(&adc->conv_completion);
        return IRQ_HANDLED;
 }
@@ -538,6 +540,7 @@ static int palmas_gpadc_start_convertion(struct palmas_gpadc *adc, int adc_chan)
        unsigned int val;
        int ret;
 
+       adc->isr_done = false;
        INIT_COMPLETION(adc->conv_completion);
        ret = palmas_update_bits(adc->palmas, PALMAS_GPADC_BASE,
                                PALMAS_GPADC_SW_SELECT,
@@ -552,6 +555,19 @@ static int palmas_gpadc_start_convertion(struct palmas_gpadc *adc, int adc_chan)
                                ADC_CONVERTION_TIMEOUT);
        if (ret == 0) {
                dev_err(adc->dev, "ADC conversion not completed\n");
+               dev_err(adc->dev, "Channel %d ISR status %d\n", adc_chan, adc->isr_done);
+               ret = palmas_read(adc->palmas, PALMAS_GPADC_BASE,
+                               PALMAS_GPADC_STATUS, &val);
+               dev_err(adc->dev, "GPADC_STATUS read st %d and val 0x%02x\n", ret, val);
+               ret = palmas_read(adc->palmas, PALMAS_GPADC_BASE,
+                               PALMAS_GPADC_SW_SELECT, &val);
+               dev_err(adc->dev, "GPADC_SW_SELECT read st %d and val 0x%02x\n", ret, val);
+               ret = palmas_read(adc->palmas, PALMAS_GPADC_BASE,
+                               PALMAS_GPADC_AUTO_CTRL, &val);
+               dev_err(adc->dev, "GPADC_AUTO_CTRL read st %d and val 0x%02x\n", ret, val);
+               ret = palmas_read(adc->palmas, PALMAS_GPADC_BASE,
+                               PALMAS_GPADC_RT_CTRL, &val);
+               dev_err(adc->dev, "GPADC_RT_CTRL read st %d and val 0x%02x\n", ret, val);
                ret = -ETIMEDOUT;
                return ret;
        }