From 06e3fe89988b1c99a3d9953b1d3b1faf3f047017 Mon Sep 17 00:00:00 2001 From: Fabrice Gasnier Date: Thu, 27 Jul 2017 18:18:59 +0200 Subject: [PATCH] iio: trigger: stm32-timer: fix get/set down count direction Fixes: 4adec7da0536 ("iio: stm32 trigger: Add quadrature encoder device") This fixes two issues: - stm32_set_count_direction: to set down direction - stm32_get_count_direction: to get down direction IIO core provides/expects value to be an index of iio_enum items array. This needs to be turned by these routines into TIM_CR1_DIR (e.g. BIT(4)) value. Also, report error when attempting to write direction, when in encoder mode: in this case, direction is read only (given by encoder inputs). Signed-off-by: Fabrice Gasnier Acked-by: Benjamin Gaignard Signed-off-by: Jonathan Cameron --- drivers/iio/trigger/stm32-timer-trigger.c | 15 +++++++++++---- 1 file changed, 11 insertions(+), 4 deletions(-) diff --git a/drivers/iio/trigger/stm32-timer-trigger.c b/drivers/iio/trigger/stm32-timer-trigger.c index 107918b3a90b..d28aa02b85e8 100644 --- a/drivers/iio/trigger/stm32-timer-trigger.c +++ b/drivers/iio/trigger/stm32-timer-trigger.c @@ -594,13 +594,20 @@ static const char *const stm32_count_direction_states[] = { static int stm32_set_count_direction(struct iio_dev *indio_dev, const struct iio_chan_spec *chan, - unsigned int mode) + unsigned int dir) { struct stm32_timer_trigger *priv = iio_priv(indio_dev); + u32 val; + int mode; - regmap_update_bits(priv->regmap, TIM_CR1, TIM_CR1_DIR, mode); + /* In encoder mode, direction is RO (given by TI1/TI2 signals) */ + regmap_read(priv->regmap, TIM_SMCR, &val); + mode = (val & TIM_SMCR_SMS) - 1; + if ((mode >= 0) || (mode < ARRAY_SIZE(stm32_quadrature_modes))) + return -EBUSY; - return 0; + return regmap_update_bits(priv->regmap, TIM_CR1, TIM_CR1_DIR, + dir ? TIM_CR1_DIR : 0); } static int stm32_get_count_direction(struct iio_dev *indio_dev, @@ -611,7 +618,7 @@ static int stm32_get_count_direction(struct iio_dev *indio_dev, regmap_read(priv->regmap, TIM_CR1, &cr1); - return (cr1 & TIM_CR1_DIR); + return ((cr1 & TIM_CR1_DIR) ? 1 : 0); } static const struct iio_enum stm32_count_direction_enum = {