[v3,2/2] iio: stm32 trigger: Add counter enable modes

Message ID 1490607804-24889-3-git-send-email-benjamin.gaignard@st.com
State Superseded
Headers show
Series
  • iio: stm32 trigger: Add quadrature device and counter
Related show

Commit Message

Benjamin Gaignard March 27, 2017, 9:43 a.m.
Device counting could be controlled by the level or the edges of
a trigger.
in_count0_enable_mode attibute allow to set the control mode.

Signed-off-by: Benjamin Gaignard <benjamin.gaignard@st.com>

---
 .../ABI/testing/sysfs-bus-iio-timer-stm32          | 23 +++++++
 drivers/iio/trigger/stm32-timer-trigger.c          | 70 ++++++++++++++++++++++
 2 files changed, 93 insertions(+)

-- 
1.9.1

Comments

William Breathitt Gray March 27, 2017, 1:55 p.m. | #1
On Mon, Mar 27, 2017 at 11:43:24AM +0200, Benjamin Gaignard wrote:
>Device counting could be controlled by the level or the edges of

>a trigger.

>in_count0_enable_mode attibute allow to set the control mode.

>

>Signed-off-by: Benjamin Gaignard <benjamin.gaignard@st.com>


This patch is pretty straight-forward and all right with me. A minor
nitpick inline regarding documentation.

Reviewed-by: William Breathitt Gray <vilhelm.gray@gmail.com>


>---

> .../ABI/testing/sysfs-bus-iio-timer-stm32          | 23 +++++++

> drivers/iio/trigger/stm32-timer-trigger.c          | 70 ++++++++++++++++++++++

> 2 files changed, 93 insertions(+)

>

>diff --git a/Documentation/ABI/testing/sysfs-bus-iio-timer-stm32 b/Documentation/ABI/testing/sysfs-bus-iio-timer-stm32

>index bf795ad..c0a1edc 100644

>--- a/Documentation/ABI/testing/sysfs-bus-iio-timer-stm32

>+++ b/Documentation/ABI/testing/sysfs-bus-iio-timer-stm32

>@@ -59,3 +59,26 @@ Description:

> 		quadrature:

> 			Encoder A and B inputs are mixed to get direction

> 			and count with a scale of 0.25.

>+

>+What:		/sys/bus/iio/devices/iio:deviceX/in_count_enable_mode_available

>+KernelVersion:	4.12

>+Contact:	benjamin.gaignard@st.com

>+Description:

>+		Reading returns the list possible enable modes.

>+

>+What:		/sys/bus/iio/devices/iio:deviceX/in_count0_enable_mode

>+KernelVersion:	4.12

>+Contact:	benjamin.gaignard@st.com

>+Description:

>+		Configure the device counter enable modes, in all case

>+		counting direction is set by in_count0_count_direction

>+		attribute and the counter is clocked by the internal clock.

>+		always:

>+			Counter is always ON.

>+

>+		gated:

>+			Counting is enabled when connected trigger signal

>+			level is high else counting is disabled.

>+

>+		triggered:

>+			Counting start on rising edge of the connected trigger.


When I read the description of the "triggered" mode, I get the
impression that counting is restarted every time there is a rising edge
from the connected trigger signal. However, from our previous
discussions I believe this mode is simply a latched enable.

Perhaps it may be beneficial for clarity to rework the description to
say something along the lines of: "Counting is enabled on rising edge of
the connected trigger, and remains enabled for the duration of this
selected mode."

William Breathitt Gray

>diff --git a/drivers/iio/trigger/stm32-timer-trigger.c b/drivers/iio/trigger/stm32-timer-trigger.c

>index 7db904c..0f1a2cf 100644

>--- a/drivers/iio/trigger/stm32-timer-trigger.c

>+++ b/drivers/iio/trigger/stm32-timer-trigger.c

>@@ -353,6 +353,74 @@ static int stm32_counter_write_raw(struct iio_dev *indio_dev,

> 	.write_raw = stm32_counter_write_raw

> };

> 

>+static const char *const stm32_enable_modes[] = {

>+	"always",

>+	"gated",

>+	"triggered",

>+};

>+

>+static int stm32_enable_mode2sms(int mode)

>+{

>+	switch (mode) {

>+	case 0:

>+		return 0;

>+	case 1:

>+		return 5;

>+	case 2:

>+		return 6;

>+	}

>+

>+	return -EINVAL;

>+}

>+

>+static int stm32_set_enable_mode(struct iio_dev *indio_dev,

>+				 const struct iio_chan_spec *chan,

>+				 unsigned int mode)

>+{

>+	struct stm32_timer_trigger *priv = iio_priv(indio_dev);

>+	int sms = stm32_enable_mode2sms(mode);

>+

>+	if (sms < 0)

>+		return sms;

>+

>+	regmap_update_bits(priv->regmap, TIM_SMCR, TIM_SMCR_SMS, sms);

>+

>+	return 0;

>+}

>+

>+static int stm32_sms2enable_mode(int mode)

>+{

>+	switch (mode) {

>+	case 0:

>+		return 0;

>+	case 5:

>+		return 1;

>+	case 6:

>+		return 2;

>+	}

>+

>+	return -EINVAL;

>+}

>+

>+static int stm32_get_enable_mode(struct iio_dev *indio_dev,

>+				 const struct iio_chan_spec *chan)

>+{

>+	struct stm32_timer_trigger *priv = iio_priv(indio_dev);

>+	u32 smcr;

>+

>+	regmap_read(priv->regmap, TIM_SMCR, &smcr);

>+	smcr &= TIM_SMCR_SMS;

>+

>+	return stm32_sms2enable_mode(smcr);

>+}

>+

>+static const struct iio_enum stm32_enable_mode_enum = {

>+	.items = stm32_enable_modes,

>+	.num_items = ARRAY_SIZE(stm32_enable_modes),

>+	.set = stm32_set_enable_mode,

>+	.get = stm32_get_enable_mode

>+};

>+

> static const char *const stm32_quadrature_modes[] = {

> 	"channel_A",

> 	"channel_B",

>@@ -466,6 +534,8 @@ static ssize_t stm32_count_set_preset(struct iio_dev *indio_dev,

> 	IIO_ENUM_AVAILABLE("count_direction", &stm32_count_direction_enum),

> 	IIO_ENUM("quadrature_mode", IIO_SEPARATE, &stm32_quadrature_mode_enum),

> 	IIO_ENUM_AVAILABLE("quadrature_mode", &stm32_quadrature_mode_enum),

>+	IIO_ENUM("enable_mode", IIO_SEPARATE, &stm32_enable_mode_enum),

>+	IIO_ENUM_AVAILABLE("enable_mode", &stm32_enable_mode_enum),

> 	{}

> };

> 

>-- 

>1.9.1

>
Benjamin Gaignard March 27, 2017, 2:43 p.m. | #2
2017-03-27 15:55 GMT+02:00 William Breathitt Gray <vilhelm.gray@gmail.com>:
> On Mon, Mar 27, 2017 at 11:43:24AM +0200, Benjamin Gaignard wrote:

>>Device counting could be controlled by the level or the edges of

>>a trigger.

>>in_count0_enable_mode attibute allow to set the control mode.

>>

>>Signed-off-by: Benjamin Gaignard <benjamin.gaignard@st.com>

>

> This patch is pretty straight-forward and all right with me. A minor

> nitpick inline regarding documentation.

>

> Reviewed-by: William Breathitt Gray <vilhelm.gray@gmail.com>

>

>>---

>> .../ABI/testing/sysfs-bus-iio-timer-stm32          | 23 +++++++

>> drivers/iio/trigger/stm32-timer-trigger.c          | 70 ++++++++++++++++++++++

>> 2 files changed, 93 insertions(+)

>>

>>diff --git a/Documentation/ABI/testing/sysfs-bus-iio-timer-stm32 b/Documentation/ABI/testing/sysfs-bus-iio-timer-stm32

>>index bf795ad..c0a1edc 100644

>>--- a/Documentation/ABI/testing/sysfs-bus-iio-timer-stm32

>>+++ b/Documentation/ABI/testing/sysfs-bus-iio-timer-stm32

>>@@ -59,3 +59,26 @@ Description:

>>               quadrature:

>>                       Encoder A and B inputs are mixed to get direction

>>                       and count with a scale of 0.25.

>>+

>>+What:         /sys/bus/iio/devices/iio:deviceX/in_count_enable_mode_available

>>+KernelVersion:        4.12

>>+Contact:      benjamin.gaignard@st.com

>>+Description:

>>+              Reading returns the list possible enable modes.

>>+

>>+What:         /sys/bus/iio/devices/iio:deviceX/in_count0_enable_mode

>>+KernelVersion:        4.12

>>+Contact:      benjamin.gaignard@st.com

>>+Description:

>>+              Configure the device counter enable modes, in all case

>>+              counting direction is set by in_count0_count_direction

>>+              attribute and the counter is clocked by the internal clock.

>>+              always:

>>+                      Counter is always ON.

>>+

>>+              gated:

>>+                      Counting is enabled when connected trigger signal

>>+                      level is high else counting is disabled.

>>+

>>+              triggered:

>>+                      Counting start on rising edge of the connected trigger.

>

> When I read the description of the "triggered" mode, I get the

> impression that counting is restarted every time there is a rising edge

> from the connected trigger signal. However, from our previous

> discussions I believe this mode is simply a latched enable.

>

> Perhaps it may be beneficial for clarity to rework the description to

> say something along the lines of: "Counting is enabled on rising edge of

> the connected trigger, and remains enabled for the duration of this

> selected mode."


I will update that in v4.

Thanks

>

> William Breathitt Gray

>

>>diff --git a/drivers/iio/trigger/stm32-timer-trigger.c b/drivers/iio/trigger/stm32-timer-trigger.c

>>index 7db904c..0f1a2cf 100644

>>--- a/drivers/iio/trigger/stm32-timer-trigger.c

>>+++ b/drivers/iio/trigger/stm32-timer-trigger.c

>>@@ -353,6 +353,74 @@ static int stm32_counter_write_raw(struct iio_dev *indio_dev,

>>       .write_raw = stm32_counter_write_raw

>> };

>>

>>+static const char *const stm32_enable_modes[] = {

>>+      "always",

>>+      "gated",

>>+      "triggered",

>>+};

>>+

>>+static int stm32_enable_mode2sms(int mode)

>>+{

>>+      switch (mode) {

>>+      case 0:

>>+              return 0;

>>+      case 1:

>>+              return 5;

>>+      case 2:

>>+              return 6;

>>+      }

>>+

>>+      return -EINVAL;

>>+}

>>+

>>+static int stm32_set_enable_mode(struct iio_dev *indio_dev,

>>+                               const struct iio_chan_spec *chan,

>>+                               unsigned int mode)

>>+{

>>+      struct stm32_timer_trigger *priv = iio_priv(indio_dev);

>>+      int sms = stm32_enable_mode2sms(mode);

>>+

>>+      if (sms < 0)

>>+              return sms;

>>+

>>+      regmap_update_bits(priv->regmap, TIM_SMCR, TIM_SMCR_SMS, sms);

>>+

>>+      return 0;

>>+}

>>+

>>+static int stm32_sms2enable_mode(int mode)

>>+{

>>+      switch (mode) {

>>+      case 0:

>>+              return 0;

>>+      case 5:

>>+              return 1;

>>+      case 6:

>>+              return 2;

>>+      }

>>+

>>+      return -EINVAL;

>>+}

>>+

>>+static int stm32_get_enable_mode(struct iio_dev *indio_dev,

>>+                               const struct iio_chan_spec *chan)

>>+{

>>+      struct stm32_timer_trigger *priv = iio_priv(indio_dev);

>>+      u32 smcr;

>>+

>>+      regmap_read(priv->regmap, TIM_SMCR, &smcr);

>>+      smcr &= TIM_SMCR_SMS;

>>+

>>+      return stm32_sms2enable_mode(smcr);

>>+}

>>+

>>+static const struct iio_enum stm32_enable_mode_enum = {

>>+      .items = stm32_enable_modes,

>>+      .num_items = ARRAY_SIZE(stm32_enable_modes),

>>+      .set = stm32_set_enable_mode,

>>+      .get = stm32_get_enable_mode

>>+};

>>+

>> static const char *const stm32_quadrature_modes[] = {

>>       "channel_A",

>>       "channel_B",

>>@@ -466,6 +534,8 @@ static ssize_t stm32_count_set_preset(struct iio_dev *indio_dev,

>>       IIO_ENUM_AVAILABLE("count_direction", &stm32_count_direction_enum),

>>       IIO_ENUM("quadrature_mode", IIO_SEPARATE, &stm32_quadrature_mode_enum),

>>       IIO_ENUM_AVAILABLE("quadrature_mode", &stm32_quadrature_mode_enum),

>>+      IIO_ENUM("enable_mode", IIO_SEPARATE, &stm32_enable_mode_enum),

>>+      IIO_ENUM_AVAILABLE("enable_mode", &stm32_enable_mode_enum),

>>       {}

>> };

>>

>>--

>>1.9.1

>>




-- 
Benjamin Gaignard

Graphic Study Group

Linaro.org │ Open source software for ARM SoCs

Follow Linaro: Facebook | Twitter | Blog
Jonathan Cameron April 2, 2017, 11:12 a.m. | #3
On 27/03/17 10:43, Benjamin Gaignard wrote:
> Device counting could be controlled by the level or the edges of

> a trigger.

> in_count0_enable_mode attibute allow to set the control mode.

> 

> Signed-off-by: Benjamin Gaignard <benjamin.gaignard@st.com>

> ---

>  .../ABI/testing/sysfs-bus-iio-timer-stm32          | 23 +++++++

>  drivers/iio/trigger/stm32-timer-trigger.c          | 70 ++++++++++++++++++++++

>  2 files changed, 93 insertions(+)

> 

> diff --git a/Documentation/ABI/testing/sysfs-bus-iio-timer-stm32 b/Documentation/ABI/testing/sysfs-bus-iio-timer-stm32

> index bf795ad..c0a1edc 100644

> --- a/Documentation/ABI/testing/sysfs-bus-iio-timer-stm32

> +++ b/Documentation/ABI/testing/sysfs-bus-iio-timer-stm32

> @@ -59,3 +59,26 @@ Description:

>  		quadrature:

>  			Encoder A and B inputs are mixed to get direction

>  			and count with a scale of 0.25.

> +

> +What:		/sys/bus/iio/devices/iio:deviceX/in_count_enable_mode_available

> +KernelVersion:	4.12

> +Contact:	benjamin.gaignard@st.com

> +Description:

> +		Reading returns the list possible enable modes.

> +

> +What:		/sys/bus/iio/devices/iio:deviceX/in_count0_enable_mode

> +KernelVersion:	4.12

> +Contact:	benjamin.gaignard@st.com

> +Description:

> +		Configure the device counter enable modes, in all case

> +		counting direction is set by in_count0_count_direction

> +		attribute and the counter is clocked by the internal clock.

Silly question, how does one use the encoder modes then?

> +		always:

> +			Counter is always ON.

> +

> +		gated:

> +			Counting is enabled when connected trigger signal

> +			level is high else counting is disabled.

> +

> +		triggered:

> +			Counting start on rising edge of the connected trigger.



> diff --git a/drivers/iio/trigger/stm32-timer-trigger.c b/drivers/iio/trigger/stm32-timer-trigger.c

> index 7db904c..0f1a2cf 100644

> --- a/drivers/iio/trigger/stm32-timer-trigger.c

> +++ b/drivers/iio/trigger/stm32-timer-trigger.c

> @@ -353,6 +353,74 @@ static int stm32_counter_write_raw(struct iio_dev *indio_dev,

>  	.write_raw = stm32_counter_write_raw

>  };

>  

> +static const char *const stm32_enable_modes[] = {

> +	"always",

> +	"gated",

> +	"triggered",

> +};

> +

> +static int stm32_enable_mode2sms(int mode)

> +{

> +	switch (mode) {

> +	case 0:

> +		return 0;

> +	case 1:

> +		return 5;

> +	case 2:

> +		return 6;

> +	}

> +

> +	return -EINVAL;

> +}

> +

> +static int stm32_set_enable_mode(struct iio_dev *indio_dev,

> +				 const struct iio_chan_spec *chan,

> +				 unsigned int mode)

> +{

> +	struct stm32_timer_trigger *priv = iio_priv(indio_dev);

> +	int sms = stm32_enable_mode2sms(mode);

> +

> +	if (sms < 0)

> +		return sms;

> +

> +	regmap_update_bits(priv->regmap, TIM_SMCR, TIM_SMCR_SMS, sms);

> +

> +	return 0;

> +}

> +

> +static int stm32_sms2enable_mode(int mode)

> +{

> +	switch (mode) {

> +	case 0:

> +		return 0;

> +	case 5:

> +		return 1;

> +	case 6:

> +		return 2;

> +	}

> +

> +	return -EINVAL;

> +}

> +

> +static int stm32_get_enable_mode(struct iio_dev *indio_dev,

> +				 const struct iio_chan_spec *chan)

> +{

> +	struct stm32_timer_trigger *priv = iio_priv(indio_dev);

> +	u32 smcr;

> +

> +	regmap_read(priv->regmap, TIM_SMCR, &smcr);

> +	smcr &= TIM_SMCR_SMS;

> +

> +	return stm32_sms2enable_mode(smcr);

> +}

> +

> +static const struct iio_enum stm32_enable_mode_enum = {

> +	.items = stm32_enable_modes,

> +	.num_items = ARRAY_SIZE(stm32_enable_modes),

> +	.set = stm32_set_enable_mode,

> +	.get = stm32_get_enable_mode

> +};

> +

>  static const char *const stm32_quadrature_modes[] = {

>  	"channel_A",

>  	"channel_B",

> @@ -466,6 +534,8 @@ static ssize_t stm32_count_set_preset(struct iio_dev *indio_dev,

>  	IIO_ENUM_AVAILABLE("count_direction", &stm32_count_direction_enum),

>  	IIO_ENUM("quadrature_mode", IIO_SEPARATE, &stm32_quadrature_mode_enum),

>  	IIO_ENUM_AVAILABLE("quadrature_mode", &stm32_quadrature_mode_enum),

> +	IIO_ENUM("enable_mode", IIO_SEPARATE, &stm32_enable_mode_enum),

> +	IIO_ENUM_AVAILABLE("enable_mode", &stm32_enable_mode_enum),

>  	{}

>  };

>  

>
Benjamin Gaignard April 3, 2017, 10:17 a.m. | #4
2017-04-02 13:12 GMT+02:00 Jonathan Cameron <jic23@kernel.org>:
> On 27/03/17 10:43, Benjamin Gaignard wrote:

>> Device counting could be controlled by the level or the edges of

>> a trigger.

>> in_count0_enable_mode attibute allow to set the control mode.

>>

>> Signed-off-by: Benjamin Gaignard <benjamin.gaignard@st.com>

>> ---

>>  .../ABI/testing/sysfs-bus-iio-timer-stm32          | 23 +++++++

>>  drivers/iio/trigger/stm32-timer-trigger.c          | 70 ++++++++++++++++++++++

>>  2 files changed, 93 insertions(+)

>>

>> diff --git a/Documentation/ABI/testing/sysfs-bus-iio-timer-stm32 b/Documentation/ABI/testing/sysfs-bus-iio-timer-stm32

>> index bf795ad..c0a1edc 100644

>> --- a/Documentation/ABI/testing/sysfs-bus-iio-timer-stm32

>> +++ b/Documentation/ABI/testing/sysfs-bus-iio-timer-stm32

>> @@ -59,3 +59,26 @@ Description:

>>               quadrature:

>>                       Encoder A and B inputs are mixed to get direction

>>                       and count with a scale of 0.25.

>> +

>> +What:                /sys/bus/iio/devices/iio:deviceX/in_count_enable_mode_available

>> +KernelVersion:       4.12

>> +Contact:     benjamin.gaignard@st.com

>> +Description:

>> +             Reading returns the list possible enable modes.

>> +

>> +What:                /sys/bus/iio/devices/iio:deviceX/in_count0_enable_mode

>> +KernelVersion:       4.12

>> +Contact:     benjamin.gaignard@st.com

>> +Description:

>> +             Configure the device counter enable modes, in all case

>> +             counting direction is set by in_count0_count_direction

>> +             attribute and the counter is clocked by the internal clock.

> Silly question, how does one use the encoder modes then?


When setting an encoder mode internal counter is enabled no need to touch to
in_count0_enable_mode in those cases

>

>> +             always:

>> +                     Counter is always ON.

>> +

>> +             gated:

>> +                     Counting is enabled when connected trigger signal

>> +                     level is high else counting is disabled.

>> +

>> +             triggered:

>> +                     Counting start on rising edge of the connected trigger.

>

>

>> diff --git a/drivers/iio/trigger/stm32-timer-trigger.c b/drivers/iio/trigger/stm32-timer-trigger.c

>> index 7db904c..0f1a2cf 100644

>> --- a/drivers/iio/trigger/stm32-timer-trigger.c

>> +++ b/drivers/iio/trigger/stm32-timer-trigger.c

>> @@ -353,6 +353,74 @@ static int stm32_counter_write_raw(struct iio_dev *indio_dev,

>>       .write_raw = stm32_counter_write_raw

>>  };

>>

>> +static const char *const stm32_enable_modes[] = {

>> +     "always",

>> +     "gated",

>> +     "triggered",

>> +};

>> +

>> +static int stm32_enable_mode2sms(int mode)

>> +{

>> +     switch (mode) {

>> +     case 0:

>> +             return 0;

>> +     case 1:

>> +             return 5;

>> +     case 2:

>> +             return 6;

>> +     }

>> +

>> +     return -EINVAL;

>> +}

>> +

>> +static int stm32_set_enable_mode(struct iio_dev *indio_dev,

>> +                              const struct iio_chan_spec *chan,

>> +                              unsigned int mode)

>> +{

>> +     struct stm32_timer_trigger *priv = iio_priv(indio_dev);

>> +     int sms = stm32_enable_mode2sms(mode);

>> +

>> +     if (sms < 0)

>> +             return sms;

>> +

>> +     regmap_update_bits(priv->regmap, TIM_SMCR, TIM_SMCR_SMS, sms);

>> +

>> +     return 0;

>> +}

>> +

>> +static int stm32_sms2enable_mode(int mode)

>> +{

>> +     switch (mode) {

>> +     case 0:

>> +             return 0;

>> +     case 5:

>> +             return 1;

>> +     case 6:

>> +             return 2;

>> +     }

>> +

>> +     return -EINVAL;

>> +}

>> +

>> +static int stm32_get_enable_mode(struct iio_dev *indio_dev,

>> +                              const struct iio_chan_spec *chan)

>> +{

>> +     struct stm32_timer_trigger *priv = iio_priv(indio_dev);

>> +     u32 smcr;

>> +

>> +     regmap_read(priv->regmap, TIM_SMCR, &smcr);

>> +     smcr &= TIM_SMCR_SMS;

>> +

>> +     return stm32_sms2enable_mode(smcr);

>> +}

>> +

>> +static const struct iio_enum stm32_enable_mode_enum = {

>> +     .items = stm32_enable_modes,

>> +     .num_items = ARRAY_SIZE(stm32_enable_modes),

>> +     .set = stm32_set_enable_mode,

>> +     .get = stm32_get_enable_mode

>> +};

>> +

>>  static const char *const stm32_quadrature_modes[] = {

>>       "channel_A",

>>       "channel_B",

>> @@ -466,6 +534,8 @@ static ssize_t stm32_count_set_preset(struct iio_dev *indio_dev,

>>       IIO_ENUM_AVAILABLE("count_direction", &stm32_count_direction_enum),

>>       IIO_ENUM("quadrature_mode", IIO_SEPARATE, &stm32_quadrature_mode_enum),

>>       IIO_ENUM_AVAILABLE("quadrature_mode", &stm32_quadrature_mode_enum),

>> +     IIO_ENUM("enable_mode", IIO_SEPARATE, &stm32_enable_mode_enum),

>> +     IIO_ENUM_AVAILABLE("enable_mode", &stm32_enable_mode_enum),

>>       {}

>>  };

>>

>>

>




-- 
Benjamin Gaignard

Graphic Study Group

Linaro.org │ Open source software for ARM SoCs

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Jonathan Cameron April 3, 2017, 7:58 p.m. | #5
On 03/04/17 11:17, Benjamin Gaignard wrote:
> 2017-04-02 13:12 GMT+02:00 Jonathan Cameron <jic23@kernel.org>:

>> On 27/03/17 10:43, Benjamin Gaignard wrote:

>>> Device counting could be controlled by the level or the edges of

>>> a trigger.

>>> in_count0_enable_mode attibute allow to set the control mode.

>>>

>>> Signed-off-by: Benjamin Gaignard <benjamin.gaignard@st.com>

>>> ---

>>>  .../ABI/testing/sysfs-bus-iio-timer-stm32          | 23 +++++++

>>>  drivers/iio/trigger/stm32-timer-trigger.c          | 70 ++++++++++++++++++++++

>>>  2 files changed, 93 insertions(+)

>>>

>>> diff --git a/Documentation/ABI/testing/sysfs-bus-iio-timer-stm32 b/Documentation/ABI/testing/sysfs-bus-iio-timer-stm32

>>> index bf795ad..c0a1edc 100644

>>> --- a/Documentation/ABI/testing/sysfs-bus-iio-timer-stm32

>>> +++ b/Documentation/ABI/testing/sysfs-bus-iio-timer-stm32

>>> @@ -59,3 +59,26 @@ Description:

>>>               quadrature:

>>>                       Encoder A and B inputs are mixed to get direction

>>>                       and count with a scale of 0.25.

>>> +

>>> +What:                /sys/bus/iio/devices/iio:deviceX/in_count_enable_mode_available

>>> +KernelVersion:       4.12

>>> +Contact:     benjamin.gaignard@st.com

>>> +Description:

>>> +             Reading returns the list possible enable modes.

>>> +

>>> +What:                /sys/bus/iio/devices/iio:deviceX/in_count0_enable_mode

>>> +KernelVersion:       4.12

>>> +Contact:     benjamin.gaignard@st.com

>>> +Description:

>>> +             Configure the device counter enable modes, in all case

>>> +             counting direction is set by in_count0_count_direction

>>> +             attribute and the counter is clocked by the internal clock.

>> Silly question, how does one use the encoder modes then?

> 

> When setting an encoder mode internal counter is enabled no need to touch to

> in_count0_enable_mode in those cases

So in that case it's ignored? 
I'd be tempted to change the docs to drop the fact it is an internal clock.
However you'll also need to ensure that when an encoder mode is selected
this attribute will always read 'always'.   I think that ends up consistent..

Also there will be other devices that do these gating and triggering etc but
will do it even when fed by an encoder.

Jonathan
> 

>>

>>> +             always:

>>> +                     Counter is always ON.

>>> +

>>> +             gated:

>>> +                     Counting is enabled when connected trigger signal

>>> +                     level is high else counting is disabled.

>>> +

>>> +             triggered:

>>> +                     Counting start on rising edge of the connected trigger.

>>

>>

>>> diff --git a/drivers/iio/trigger/stm32-timer-trigger.c b/drivers/iio/trigger/stm32-timer-trigger.c

>>> index 7db904c..0f1a2cf 100644

>>> --- a/drivers/iio/trigger/stm32-timer-trigger.c

>>> +++ b/drivers/iio/trigger/stm32-timer-trigger.c

>>> @@ -353,6 +353,74 @@ static int stm32_counter_write_raw(struct iio_dev *indio_dev,

>>>       .write_raw = stm32_counter_write_raw

>>>  };

>>>

>>> +static const char *const stm32_enable_modes[] = {

>>> +     "always",

>>> +     "gated",

>>> +     "triggered",

>>> +};

>>> +

>>> +static int stm32_enable_mode2sms(int mode)

>>> +{

>>> +     switch (mode) {

>>> +     case 0:

>>> +             return 0;

>>> +     case 1:

>>> +             return 5;

>>> +     case 2:

>>> +             return 6;

>>> +     }

>>> +

>>> +     return -EINVAL;

>>> +}

>>> +

>>> +static int stm32_set_enable_mode(struct iio_dev *indio_dev,

>>> +                              const struct iio_chan_spec *chan,

>>> +                              unsigned int mode)

>>> +{

>>> +     struct stm32_timer_trigger *priv = iio_priv(indio_dev);

>>> +     int sms = stm32_enable_mode2sms(mode);

>>> +

>>> +     if (sms < 0)

>>> +             return sms;

>>> +

>>> +     regmap_update_bits(priv->regmap, TIM_SMCR, TIM_SMCR_SMS, sms);

>>> +

>>> +     return 0;

>>> +}

>>> +

>>> +static int stm32_sms2enable_mode(int mode)

>>> +{

>>> +     switch (mode) {

>>> +     case 0:

>>> +             return 0;

>>> +     case 5:

>>> +             return 1;

>>> +     case 6:

>>> +             return 2;

>>> +     }

>>> +

>>> +     return -EINVAL;

>>> +}

>>> +

>>> +static int stm32_get_enable_mode(struct iio_dev *indio_dev,

>>> +                              const struct iio_chan_spec *chan)

>>> +{

>>> +     struct stm32_timer_trigger *priv = iio_priv(indio_dev);

>>> +     u32 smcr;

>>> +

>>> +     regmap_read(priv->regmap, TIM_SMCR, &smcr);

>>> +     smcr &= TIM_SMCR_SMS;

>>> +

>>> +     return stm32_sms2enable_mode(smcr);

>>> +}

>>> +

>>> +static const struct iio_enum stm32_enable_mode_enum = {

>>> +     .items = stm32_enable_modes,

>>> +     .num_items = ARRAY_SIZE(stm32_enable_modes),

>>> +     .set = stm32_set_enable_mode,

>>> +     .get = stm32_get_enable_mode

>>> +};

>>> +

>>>  static const char *const stm32_quadrature_modes[] = {

>>>       "channel_A",

>>>       "channel_B",

>>> @@ -466,6 +534,8 @@ static ssize_t stm32_count_set_preset(struct iio_dev *indio_dev,

>>>       IIO_ENUM_AVAILABLE("count_direction", &stm32_count_direction_enum),

>>>       IIO_ENUM("quadrature_mode", IIO_SEPARATE, &stm32_quadrature_mode_enum),

>>>       IIO_ENUM_AVAILABLE("quadrature_mode", &stm32_quadrature_mode_enum),

>>> +     IIO_ENUM("enable_mode", IIO_SEPARATE, &stm32_enable_mode_enum),

>>> +     IIO_ENUM_AVAILABLE("enable_mode", &stm32_enable_mode_enum),

>>>       {}

>>>  };

>>>

>>>

>>

> 

> 

>
Benjamin Gaignard April 4, 2017, 7:37 a.m. | #6
2017-04-03 21:58 GMT+02:00 Jonathan Cameron <jic23@kernel.org>:
> On 03/04/17 11:17, Benjamin Gaignard wrote:

>> 2017-04-02 13:12 GMT+02:00 Jonathan Cameron <jic23@kernel.org>:

>>> On 27/03/17 10:43, Benjamin Gaignard wrote:

>>>> Device counting could be controlled by the level or the edges of

>>>> a trigger.

>>>> in_count0_enable_mode attibute allow to set the control mode.

>>>>

>>>> Signed-off-by: Benjamin Gaignard <benjamin.gaignard@st.com>

>>>> ---

>>>>  .../ABI/testing/sysfs-bus-iio-timer-stm32          | 23 +++++++

>>>>  drivers/iio/trigger/stm32-timer-trigger.c          | 70 ++++++++++++++++++++++

>>>>  2 files changed, 93 insertions(+)

>>>>

>>>> diff --git a/Documentation/ABI/testing/sysfs-bus-iio-timer-stm32 b/Documentation/ABI/testing/sysfs-bus-iio-timer-stm32

>>>> index bf795ad..c0a1edc 100644

>>>> --- a/Documentation/ABI/testing/sysfs-bus-iio-timer-stm32

>>>> +++ b/Documentation/ABI/testing/sysfs-bus-iio-timer-stm32

>>>> @@ -59,3 +59,26 @@ Description:

>>>>               quadrature:

>>>>                       Encoder A and B inputs are mixed to get direction

>>>>                       and count with a scale of 0.25.

>>>> +

>>>> +What:                /sys/bus/iio/devices/iio:deviceX/in_count_enable_mode_available

>>>> +KernelVersion:       4.12

>>>> +Contact:     benjamin.gaignard@st.com

>>>> +Description:

>>>> +             Reading returns the list possible enable modes.

>>>> +

>>>> +What:                /sys/bus/iio/devices/iio:deviceX/in_count0_enable_mode

>>>> +KernelVersion:       4.12

>>>> +Contact:     benjamin.gaignard@st.com

>>>> +Description:

>>>> +             Configure the device counter enable modes, in all case

>>>> +             counting direction is set by in_count0_count_direction

>>>> +             attribute and the counter is clocked by the internal clock.

>>> Silly question, how does one use the encoder modes then?

>>

>> When setting an encoder mode internal counter is enabled no need to touch to

>> in_count0_enable_mode in those cases

> So in that case it's ignored?

> I'd be tempted to change the docs to drop the fact it is an internal clock.

> However you'll also need to ensure that when an encoder mode is selected

> this attribute will always read 'always'.   I think that ends up consistent..


The counter could be drive (i.e counting up/down) by 3 type of source:
- the internal clock with 3 modes "always", "gated" and "triggered"
- the encoder input egdes and levels: 3 modes "channel_A", "channel_B"
and "quadrature"
- the rising egdes of a  connected trigger which is an internal signal
(for a later patch)

For each counter "source" I have an attribute but in the hardware they
are exclusive.
For example set "quadrature" means that the counter is counting on the edges of
encoder inputs and no more on the rising edges of the internal clock.

I would like to keep this representing the hardware status so if an
encoder mode is
selected in_count0_enable_mode will return -EINVAL.

>

> Also there will be other devices that do these gating and triggering etc but

> will do it even when fed by an encoder.

>

> Jonathan

>>

>>>

>>>> +             always:

>>>> +                     Counter is always ON.

>>>> +

>>>> +             gated:

>>>> +                     Counting is enabled when connected trigger signal

>>>> +                     level is high else counting is disabled.

>>>> +

>>>> +             triggered:

>>>> +                     Counting start on rising edge of the connected trigger.

>>>

>>>

>>>> diff --git a/drivers/iio/trigger/stm32-timer-trigger.c b/drivers/iio/trigger/stm32-timer-trigger.c

>>>> index 7db904c..0f1a2cf 100644

>>>> --- a/drivers/iio/trigger/stm32-timer-trigger.c

>>>> +++ b/drivers/iio/trigger/stm32-timer-trigger.c

>>>> @@ -353,6 +353,74 @@ static int stm32_counter_write_raw(struct iio_dev *indio_dev,

>>>>       .write_raw = stm32_counter_write_raw

>>>>  };

>>>>

>>>> +static const char *const stm32_enable_modes[] = {

>>>> +     "always",

>>>> +     "gated",

>>>> +     "triggered",

>>>> +};

>>>> +

>>>> +static int stm32_enable_mode2sms(int mode)

>>>> +{

>>>> +     switch (mode) {

>>>> +     case 0:

>>>> +             return 0;

>>>> +     case 1:

>>>> +             return 5;

>>>> +     case 2:

>>>> +             return 6;

>>>> +     }

>>>> +

>>>> +     return -EINVAL;

>>>> +}

>>>> +

>>>> +static int stm32_set_enable_mode(struct iio_dev *indio_dev,

>>>> +                              const struct iio_chan_spec *chan,

>>>> +                              unsigned int mode)

>>>> +{

>>>> +     struct stm32_timer_trigger *priv = iio_priv(indio_dev);

>>>> +     int sms = stm32_enable_mode2sms(mode);

>>>> +

>>>> +     if (sms < 0)

>>>> +             return sms;

>>>> +

>>>> +     regmap_update_bits(priv->regmap, TIM_SMCR, TIM_SMCR_SMS, sms);

>>>> +

>>>> +     return 0;

>>>> +}

>>>> +

>>>> +static int stm32_sms2enable_mode(int mode)

>>>> +{

>>>> +     switch (mode) {

>>>> +     case 0:

>>>> +             return 0;

>>>> +     case 5:

>>>> +             return 1;

>>>> +     case 6:

>>>> +             return 2;

>>>> +     }

>>>> +

>>>> +     return -EINVAL;

>>>> +}

>>>> +

>>>> +static int stm32_get_enable_mode(struct iio_dev *indio_dev,

>>>> +                              const struct iio_chan_spec *chan)

>>>> +{

>>>> +     struct stm32_timer_trigger *priv = iio_priv(indio_dev);

>>>> +     u32 smcr;

>>>> +

>>>> +     regmap_read(priv->regmap, TIM_SMCR, &smcr);

>>>> +     smcr &= TIM_SMCR_SMS;

>>>> +

>>>> +     return stm32_sms2enable_mode(smcr);

>>>> +}

>>>> +

>>>> +static const struct iio_enum stm32_enable_mode_enum = {

>>>> +     .items = stm32_enable_modes,

>>>> +     .num_items = ARRAY_SIZE(stm32_enable_modes),

>>>> +     .set = stm32_set_enable_mode,

>>>> +     .get = stm32_get_enable_mode

>>>> +};

>>>> +

>>>>  static const char *const stm32_quadrature_modes[] = {

>>>>       "channel_A",

>>>>       "channel_B",

>>>> @@ -466,6 +534,8 @@ static ssize_t stm32_count_set_preset(struct iio_dev *indio_dev,

>>>>       IIO_ENUM_AVAILABLE("count_direction", &stm32_count_direction_enum),

>>>>       IIO_ENUM("quadrature_mode", IIO_SEPARATE, &stm32_quadrature_mode_enum),

>>>>       IIO_ENUM_AVAILABLE("quadrature_mode", &stm32_quadrature_mode_enum),

>>>> +     IIO_ENUM("enable_mode", IIO_SEPARATE, &stm32_enable_mode_enum),

>>>> +     IIO_ENUM_AVAILABLE("enable_mode", &stm32_enable_mode_enum),

>>>>       {}

>>>>  };

>>>>

>>>>

>>>

>>

>>

>>

>




-- 
Benjamin Gaignard

Graphic Study Group

Linaro.org │ Open source software for ARM SoCs

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Jonathan Cameron April 8, 2017, 5:23 p.m. | #7
On 04/04/17 08:37, Benjamin Gaignard wrote:
> 2017-04-03 21:58 GMT+02:00 Jonathan Cameron <jic23@kernel.org>:

>> On 03/04/17 11:17, Benjamin Gaignard wrote:

>>> 2017-04-02 13:12 GMT+02:00 Jonathan Cameron <jic23@kernel.org>:

>>>> On 27/03/17 10:43, Benjamin Gaignard wrote:

>>>>> Device counting could be controlled by the level or the edges of

>>>>> a trigger.

>>>>> in_count0_enable_mode attibute allow to set the control mode.

>>>>>

>>>>> Signed-off-by: Benjamin Gaignard <benjamin.gaignard@st.com>

>>>>> ---

>>>>>  .../ABI/testing/sysfs-bus-iio-timer-stm32          | 23 +++++++

>>>>>  drivers/iio/trigger/stm32-timer-trigger.c          | 70 ++++++++++++++++++++++

>>>>>  2 files changed, 93 insertions(+)

>>>>>

>>>>> diff --git a/Documentation/ABI/testing/sysfs-bus-iio-timer-stm32 b/Documentation/ABI/testing/sysfs-bus-iio-timer-stm32

>>>>> index bf795ad..c0a1edc 100644

>>>>> --- a/Documentation/ABI/testing/sysfs-bus-iio-timer-stm32

>>>>> +++ b/Documentation/ABI/testing/sysfs-bus-iio-timer-stm32

>>>>> @@ -59,3 +59,26 @@ Description:

>>>>>               quadrature:

>>>>>                       Encoder A and B inputs are mixed to get direction

>>>>>                       and count with a scale of 0.25.

>>>>> +

>>>>> +What:                /sys/bus/iio/devices/iio:deviceX/in_count_enable_mode_available

>>>>> +KernelVersion:       4.12

>>>>> +Contact:     benjamin.gaignard@st.com

>>>>> +Description:

>>>>> +             Reading returns the list possible enable modes.

>>>>> +

>>>>> +What:                /sys/bus/iio/devices/iio:deviceX/in_count0_enable_mode

>>>>> +KernelVersion:       4.12

>>>>> +Contact:     benjamin.gaignard@st.com

>>>>> +Description:

>>>>> +             Configure the device counter enable modes, in all case

>>>>> +             counting direction is set by in_count0_count_direction

>>>>> +             attribute and the counter is clocked by the internal clock.

>>>> Silly question, how does one use the encoder modes then?

>>>

>>> When setting an encoder mode internal counter is enabled no need to touch to

>>> in_count0_enable_mode in those cases

>> So in that case it's ignored?

>> I'd be tempted to change the docs to drop the fact it is an internal clock.

>> However you'll also need to ensure that when an encoder mode is selected

>> this attribute will always read 'always'.   I think that ends up consistent..

> 

> The counter could be drive (i.e counting up/down) by 3 type of source:

> - the internal clock with 3 modes "always", "gated" and "triggered"

> - the encoder input egdes and levels: 3 modes "channel_A", "channel_B"

> and "quadrature"

> - the rising egdes of a  connected trigger which is an internal signal

> (for a later patch)

> 

> For each counter "source" I have an attribute but in the hardware they

> are exclusive.

> For example set "quadrature" means that the counter is counting on the edges of

> encoder inputs and no more on the rising edges of the internal clock.

> 

> I would like to keep this representing the hardware status so if an

> encoder mode is

> selected in_count0_enable_mode will return -EINVAL.

Cool. As long as there is a valid path between modes that's an acceptable
option.
> 

>>

>> Also there will be other devices that do these gating and triggering etc but

>> will do it even when fed by an encoder.

>>

>> Jonathan

>>>

>>>>

>>>>> +             always:

>>>>> +                     Counter is always ON.

>>>>> +

>>>>> +             gated:

>>>>> +                     Counting is enabled when connected trigger signal

>>>>> +                     level is high else counting is disabled.

>>>>> +

>>>>> +             triggered:

>>>>> +                     Counting start on rising edge of the connected trigger.

>>>>

>>>>

>>>>> diff --git a/drivers/iio/trigger/stm32-timer-trigger.c b/drivers/iio/trigger/stm32-timer-trigger.c

>>>>> index 7db904c..0f1a2cf 100644

>>>>> --- a/drivers/iio/trigger/stm32-timer-trigger.c

>>>>> +++ b/drivers/iio/trigger/stm32-timer-trigger.c

>>>>> @@ -353,6 +353,74 @@ static int stm32_counter_write_raw(struct iio_dev *indio_dev,

>>>>>       .write_raw = stm32_counter_write_raw

>>>>>  };

>>>>>

>>>>> +static const char *const stm32_enable_modes[] = {

>>>>> +     "always",

>>>>> +     "gated",

>>>>> +     "triggered",

>>>>> +};

>>>>> +

>>>>> +static int stm32_enable_mode2sms(int mode)

>>>>> +{

>>>>> +     switch (mode) {

>>>>> +     case 0:

>>>>> +             return 0;

>>>>> +     case 1:

>>>>> +             return 5;

>>>>> +     case 2:

>>>>> +             return 6;

>>>>> +     }

>>>>> +

>>>>> +     return -EINVAL;

>>>>> +}

>>>>> +

>>>>> +static int stm32_set_enable_mode(struct iio_dev *indio_dev,

>>>>> +                              const struct iio_chan_spec *chan,

>>>>> +                              unsigned int mode)

>>>>> +{

>>>>> +     struct stm32_timer_trigger *priv = iio_priv(indio_dev);

>>>>> +     int sms = stm32_enable_mode2sms(mode);

>>>>> +

>>>>> +     if (sms < 0)

>>>>> +             return sms;

>>>>> +

>>>>> +     regmap_update_bits(priv->regmap, TIM_SMCR, TIM_SMCR_SMS, sms);

>>>>> +

>>>>> +     return 0;

>>>>> +}

>>>>> +

>>>>> +static int stm32_sms2enable_mode(int mode)

>>>>> +{

>>>>> +     switch (mode) {

>>>>> +     case 0:

>>>>> +             return 0;

>>>>> +     case 5:

>>>>> +             return 1;

>>>>> +     case 6:

>>>>> +             return 2;

>>>>> +     }

>>>>> +

>>>>> +     return -EINVAL;

>>>>> +}

>>>>> +

>>>>> +static int stm32_get_enable_mode(struct iio_dev *indio_dev,

>>>>> +                              const struct iio_chan_spec *chan)

>>>>> +{

>>>>> +     struct stm32_timer_trigger *priv = iio_priv(indio_dev);

>>>>> +     u32 smcr;

>>>>> +

>>>>> +     regmap_read(priv->regmap, TIM_SMCR, &smcr);

>>>>> +     smcr &= TIM_SMCR_SMS;

>>>>> +

>>>>> +     return stm32_sms2enable_mode(smcr);

>>>>> +}

>>>>> +

>>>>> +static const struct iio_enum stm32_enable_mode_enum = {

>>>>> +     .items = stm32_enable_modes,

>>>>> +     .num_items = ARRAY_SIZE(stm32_enable_modes),

>>>>> +     .set = stm32_set_enable_mode,

>>>>> +     .get = stm32_get_enable_mode

>>>>> +};

>>>>> +

>>>>>  static const char *const stm32_quadrature_modes[] = {

>>>>>       "channel_A",

>>>>>       "channel_B",

>>>>> @@ -466,6 +534,8 @@ static ssize_t stm32_count_set_preset(struct iio_dev *indio_dev,

>>>>>       IIO_ENUM_AVAILABLE("count_direction", &stm32_count_direction_enum),

>>>>>       IIO_ENUM("quadrature_mode", IIO_SEPARATE, &stm32_quadrature_mode_enum),

>>>>>       IIO_ENUM_AVAILABLE("quadrature_mode", &stm32_quadrature_mode_enum),

>>>>> +     IIO_ENUM("enable_mode", IIO_SEPARATE, &stm32_enable_mode_enum),

>>>>> +     IIO_ENUM_AVAILABLE("enable_mode", &stm32_enable_mode_enum),

>>>>>       {}

>>>>>  };

>>>>>

>>>>>

>>>>

>>>

>>>

>>>

>>

> 

> 

>

Patch

diff --git a/Documentation/ABI/testing/sysfs-bus-iio-timer-stm32 b/Documentation/ABI/testing/sysfs-bus-iio-timer-stm32
index bf795ad..c0a1edc 100644
--- a/Documentation/ABI/testing/sysfs-bus-iio-timer-stm32
+++ b/Documentation/ABI/testing/sysfs-bus-iio-timer-stm32
@@ -59,3 +59,26 @@  Description:
 		quadrature:
 			Encoder A and B inputs are mixed to get direction
 			and count with a scale of 0.25.
+
+What:		/sys/bus/iio/devices/iio:deviceX/in_count_enable_mode_available
+KernelVersion:	4.12
+Contact:	benjamin.gaignard@st.com
+Description:
+		Reading returns the list possible enable modes.
+
+What:		/sys/bus/iio/devices/iio:deviceX/in_count0_enable_mode
+KernelVersion:	4.12
+Contact:	benjamin.gaignard@st.com
+Description:
+		Configure the device counter enable modes, in all case
+		counting direction is set by in_count0_count_direction
+		attribute and the counter is clocked by the internal clock.
+		always:
+			Counter is always ON.
+
+		gated:
+			Counting is enabled when connected trigger signal
+			level is high else counting is disabled.
+
+		triggered:
+			Counting start on rising edge of the connected trigger.
diff --git a/drivers/iio/trigger/stm32-timer-trigger.c b/drivers/iio/trigger/stm32-timer-trigger.c
index 7db904c..0f1a2cf 100644
--- a/drivers/iio/trigger/stm32-timer-trigger.c
+++ b/drivers/iio/trigger/stm32-timer-trigger.c
@@ -353,6 +353,74 @@  static int stm32_counter_write_raw(struct iio_dev *indio_dev,
 	.write_raw = stm32_counter_write_raw
 };
 
+static const char *const stm32_enable_modes[] = {
+	"always",
+	"gated",
+	"triggered",
+};
+
+static int stm32_enable_mode2sms(int mode)
+{
+	switch (mode) {
+	case 0:
+		return 0;
+	case 1:
+		return 5;
+	case 2:
+		return 6;
+	}
+
+	return -EINVAL;
+}
+
+static int stm32_set_enable_mode(struct iio_dev *indio_dev,
+				 const struct iio_chan_spec *chan,
+				 unsigned int mode)
+{
+	struct stm32_timer_trigger *priv = iio_priv(indio_dev);
+	int sms = stm32_enable_mode2sms(mode);
+
+	if (sms < 0)
+		return sms;
+
+	regmap_update_bits(priv->regmap, TIM_SMCR, TIM_SMCR_SMS, sms);
+
+	return 0;
+}
+
+static int stm32_sms2enable_mode(int mode)
+{
+	switch (mode) {
+	case 0:
+		return 0;
+	case 5:
+		return 1;
+	case 6:
+		return 2;
+	}
+
+	return -EINVAL;
+}
+
+static int stm32_get_enable_mode(struct iio_dev *indio_dev,
+				 const struct iio_chan_spec *chan)
+{
+	struct stm32_timer_trigger *priv = iio_priv(indio_dev);
+	u32 smcr;
+
+	regmap_read(priv->regmap, TIM_SMCR, &smcr);
+	smcr &= TIM_SMCR_SMS;
+
+	return stm32_sms2enable_mode(smcr);
+}
+
+static const struct iio_enum stm32_enable_mode_enum = {
+	.items = stm32_enable_modes,
+	.num_items = ARRAY_SIZE(stm32_enable_modes),
+	.set = stm32_set_enable_mode,
+	.get = stm32_get_enable_mode
+};
+
 static const char *const stm32_quadrature_modes[] = {
 	"channel_A",
 	"channel_B",
@@ -466,6 +534,8 @@  static ssize_t stm32_count_set_preset(struct iio_dev *indio_dev,
 	IIO_ENUM_AVAILABLE("count_direction", &stm32_count_direction_enum),
 	IIO_ENUM("quadrature_mode", IIO_SEPARATE, &stm32_quadrature_mode_enum),
 	IIO_ENUM_AVAILABLE("quadrature_mode", &stm32_quadrature_mode_enum),
+	IIO_ENUM("enable_mode", IIO_SEPARATE, &stm32_enable_mode_enum),
+	IIO_ENUM_AVAILABLE("enable_mode", &stm32_enable_mode_enum),
 	{}
 };