From 90938ca432e6b8f6bb1c22a24984738fc3d906ed Mon Sep 17 00:00:00 2001 From: Fabrice Gasnier Date: Thu, 27 Jul 2017 18:19:00 +0200 Subject: [PATCH] iio: trigger: stm32-timer: add enable attribute 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 Acked-by: Benjamin Gaignard Signed-off-by: Jonathan Cameron --- 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 d28aa02b85e8..14e6eb04bbb0 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 const struct iio_chan_spec_ext_info stm32_trigger_count_info[] = { 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 }; -- 2.39.5