Because unsigned integers cannot be negative, timeout variable is never less than zero. Hence, checks in Amlogic Meson ADC driver to detect timeouts always evaluated to false. Fix that.
Signed-off-by: Francois Berder fberder@outlook.fr --- Changes for v2: - Replace timeout handling logic by regmap_read_poll_timeout
drivers/adc/meson-saradc.c | 33 ++++++++++++++------------------- 1 file changed, 14 insertions(+), 19 deletions(-)
diff --git a/drivers/adc/meson-saradc.c b/drivers/adc/meson-saradc.c index 1a45a3a265..b36f09cdb1 100644 --- a/drivers/adc/meson-saradc.c +++ b/drivers/adc/meson-saradc.c @@ -192,7 +192,8 @@ meson_saradc_get_fifo_count(struct meson_saradc_priv *priv)
static int meson_saradc_lock(struct meson_saradc_priv *priv) { - uint val, timeout = 10000; + uint val; + int ret;
/* prevent BL30 from using the SAR ADC while we are using it */ regmap_update_bits(priv->regmap, MESON_SAR_ADC_DELAY, @@ -202,17 +203,14 @@ static int meson_saradc_lock(struct meson_saradc_priv *priv) /* * wait until BL30 releases it's lock (so we can use the SAR ADC) */ - do { - udelay(1); - regmap_read(priv->regmap, MESON_SAR_ADC_DELAY, &val); - } while (val & MESON_SAR_ADC_DELAY_BL30_BUSY && timeout--); - - if (timeout < 0) { + ret = + regmap_read_poll_timeout(priv->regmap, MESON_SAR_ADC_DELAY, val, + val & MESON_SAR_ADC_DELAY_BL30_BUSY, 1, + 10); + if (ret) printf("Timeout while waiting for BL30 unlock\n"); - return -ETIMEDOUT; - }
- return 0; + return ret; }
static void meson_saradc_unlock(struct meson_saradc_priv *priv) @@ -246,22 +244,19 @@ static int meson_saradc_calib_val(struct meson_saradc_priv *priv, int val)
static int meson_saradc_wait_busy_clear(struct meson_saradc_priv *priv) { - uint regval, timeout = 10000; + uint regval;
/* * NOTE: we need a small delay before reading the status, otherwise * the sample engine may not have started internally (which would * seem to us that sampling is already finished). */ - do { - udelay(1); - regmap_read(priv->regmap, MESON_SAR_ADC_REG0, ®val); - } while (FIELD_GET(MESON_SAR_ADC_REG0_BUSY_MASK, regval) && timeout--); + udelay(1);
- if (timeout < 0) - return -ETIMEDOUT; - - return 0; + return regmap_read_poll_timeout(priv->regmap, MESON_SAR_ADC_REG0, + regval, + FIELD_GET(MESON_SAR_ADC_REG0_BUSY_MASK, + regval), 1, 10); }
static int meson_saradc_read_raw_sample(struct meson_saradc_priv *priv,