On Thu, 27 Jul 2017 18:19:00 +0200
Fabrice Gasnier <fabrice.gasn...@st.com> wrote:
> In order to use encoder mode, timers needs to be enabled (e.g. CEN bit)
> along with peripheral clock.
> Add IIO_CHAN_INFO_ENABLE attribute to handle this.
> Also, in triggered mode, CEN bit is set automatically in hardware.
> Then clock must be enabled before starting triggered mode.
>
> Signed-off-by: Fabrice Gasnier <fabrice.gasn...@st.com>
This one could perhaps have been a little more compact given
it is a fix, but it's still not huge so we'll let it go.
Applied to the fixes-togreg branch of iio.git.
Thanks,
Jonathan
> ---
> drivers/iio/trigger/stm32-timer-trigger.c | 55
> +++++++++++++++++++++++--------
> 1 file changed, 41 insertions(+), 14 deletions(-)
>
> diff --git a/drivers/iio/trigger/stm32-timer-trigger.c
> b/drivers/iio/trigger/stm32-timer-trigger.c
> index d28aa02..14e6eb0 100644
> --- a/drivers/iio/trigger/stm32-timer-trigger.c
> +++ b/drivers/iio/trigger/stm32-timer-trigger.c
> @@ -366,34 +366,32 @@ static int stm32_counter_read_raw(struct iio_dev
> *indio_dev,
> int *val, int *val2, long mask)
> {
> struct stm32_timer_trigger *priv = iio_priv(indio_dev);
> + u32 dat;
>
> switch (mask) {
> case IIO_CHAN_INFO_RAW:
> - {
> - u32 cnt;
> -
> - regmap_read(priv->regmap, TIM_CNT, &cnt);
> - *val = cnt;
> + regmap_read(priv->regmap, TIM_CNT, &dat);
> + *val = dat;
> + return IIO_VAL_INT;
>
> + case IIO_CHAN_INFO_ENABLE:
> + regmap_read(priv->regmap, TIM_CR1, &dat);
> + *val = (dat & TIM_CR1_CEN) ? 1 : 0;
> return IIO_VAL_INT;
> - }
> - case IIO_CHAN_INFO_SCALE:
> - {
> - u32 smcr;
>
> - regmap_read(priv->regmap, TIM_SMCR, &smcr);
> - smcr &= TIM_SMCR_SMS;
> + case IIO_CHAN_INFO_SCALE:
> + regmap_read(priv->regmap, TIM_SMCR, &dat);
> + dat &= TIM_SMCR_SMS;
>
> *val = 1;
> *val2 = 0;
>
> /* in quadrature case scale = 0.25 */
> - if (smcr == 3)
> + if (dat == 3)
> *val2 = 2;
>
> return IIO_VAL_FRACTIONAL_LOG2;
> }
> - }
>
> return -EINVAL;
> }
> @@ -403,6 +401,7 @@ static int stm32_counter_write_raw(struct iio_dev
> *indio_dev,
> int val, int val2, long mask)
> {
> struct stm32_timer_trigger *priv = iio_priv(indio_dev);
> + u32 dat;
>
> switch (mask) {
> case IIO_CHAN_INFO_RAW:
> @@ -411,6 +410,22 @@ static int stm32_counter_write_raw(struct iio_dev
> *indio_dev,
> case IIO_CHAN_INFO_SCALE:
> /* fixed scale */
> return -EINVAL;
> +
> + case IIO_CHAN_INFO_ENABLE:
> + if (val) {
> + regmap_read(priv->regmap, TIM_CR1, &dat);
> + if (!(dat & TIM_CR1_CEN))
> + clk_enable(priv->clk);
> + regmap_update_bits(priv->regmap, TIM_CR1, TIM_CR1_CEN,
> + TIM_CR1_CEN);
> + } else {
> + regmap_read(priv->regmap, TIM_CR1, &dat);
> + regmap_update_bits(priv->regmap, TIM_CR1, TIM_CR1_CEN,
> + 0);
> + if (dat & TIM_CR1_CEN)
> + clk_disable(priv->clk);
> + }
> + return 0;
> }
>
> return -EINVAL;
> @@ -506,9 +521,19 @@ static int stm32_set_enable_mode(struct iio_dev
> *indio_dev,
> {
> struct stm32_timer_trigger *priv = iio_priv(indio_dev);
> int sms = stm32_enable_mode2sms(mode);
> + u32 val;
>
> if (sms < 0)
> return sms;
> + /*
> + * Triggered mode sets CEN bit automatically by hardware. So, first
> + * enable counter clock, so it can use it. Keeps it in sync with CEN.
> + */
> + if (sms == 6) {
> + regmap_read(priv->regmap, TIM_CR1, &val);
> + if (!(val & TIM_CR1_CEN))
> + clk_enable(priv->clk);
> + }
>
> regmap_update_bits(priv->regmap, TIM_SMCR, TIM_SMCR_SMS, sms);
>
> @@ -681,7 +706,9 @@ static ssize_t stm32_count_set_preset(struct iio_dev
> *indio_dev,
> static const struct iio_chan_spec stm32_trigger_channel = {
> .type = IIO_COUNT,
> .channel = 0,
> - .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | BIT(IIO_CHAN_INFO_SCALE),
> + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
> + BIT(IIO_CHAN_INFO_ENABLE) |
> + BIT(IIO_CHAN_INFO_SCALE),
> .ext_info = stm32_trigger_count_info,
> .indexed = 1
> };
