Commit fae6f62e authored by William Breathitt Gray's avatar William Breathitt Gray Committed by Jonathan Cameron
Browse files

counter: stm32-timer-cnt: Report count function when SLAVE_MODE_DISABLED 



When in SLAVE_MODE_DISABLED mode, the count still increases if the
counter is enabled because an internal clock is used. This patch fixes
the stm32_count_function_get() and stm32_count_function_set() functions
to properly handle this behavior.

Fixes: ad29937e ("counter: Add STM32 Timer quadrature encoder")
Cc: Fabrice Gasnier <fabrice.gasnier@st.com>
Cc: Maxime Coquelin <mcoquelin.stm32@gmail.com>
Cc: Alexandre Torgue <alexandre.torgue@st.com>
Signed-off-by: default avatarWilliam Breathitt Gray <vilhelm.gray@gmail.com>
Reviewed-by: default avatarFabrice Gasnier <fabrice.gasnier@foss.st.com>
Link: https://lore.kernel.org/r/20210226012931.161429-1-vilhelm.gray@gmail.com


Signed-off-by: default avatarJonathan Cameron <Jonathan.Cameron@huawei.com>
parent 4f543408

drivers/counter/stm32-timer-cnt.c

+25 −14
Original line number Diff line number Diff line
@@ -44,13 +44,14 @@ struct stm32_timer_cnt { 
 * @STM32_COUNT_ENCODER_MODE_3: counts on both TI1FP1 and TI2FP2 edges

 */

enum stm32_count_function {

	STM32_COUNT_SLAVE_MODE_DISABLED = -1,

	STM32_COUNT_SLAVE_MODE_DISABLED,

	STM32_COUNT_ENCODER_MODE_1,

	STM32_COUNT_ENCODER_MODE_2,

	STM32_COUNT_ENCODER_MODE_3,

};



static enum counter_count_function stm32_count_functions[] = {

	[STM32_COUNT_SLAVE_MODE_DISABLED] = COUNTER_COUNT_FUNCTION_INCREASE,

	[STM32_COUNT_ENCODER_MODE_1] = COUNTER_COUNT_FUNCTION_QUADRATURE_X2_A,

	[STM32_COUNT_ENCODER_MODE_2] = COUNTER_COUNT_FUNCTION_QUADRATURE_X2_B,

	[STM32_COUNT_ENCODER_MODE_3] = COUNTER_COUNT_FUNCTION_QUADRATURE_X4,
@@ -90,6 +91,9 @@ static int stm32_count_function_get(struct counter_device *counter, 
	regmap_read(priv->regmap, TIM_SMCR, &smcr);



	switch (smcr & TIM_SMCR_SMS) {

	case 0:

		*function = STM32_COUNT_SLAVE_MODE_DISABLED;

		return 0;

	case 1:

		*function = STM32_COUNT_ENCODER_MODE_1;

		return 0;
@@ -99,10 +103,10 @@ static int stm32_count_function_get(struct counter_device *counter, 
	case 3:

		*function = STM32_COUNT_ENCODER_MODE_3;

		return 0;

	}



	default:

		return -EINVAL;

	}

}



static int stm32_count_function_set(struct counter_device *counter,

				    struct counter_count *count,
@@ -112,6 +116,9 @@ static int stm32_count_function_set(struct counter_device *counter, 
	u32 cr1, sms;



	switch (function) {

	case STM32_COUNT_SLAVE_MODE_DISABLED:

		sms = 0;

		break;

	case STM32_COUNT_ENCODER_MODE_1:

		sms = 1;

		break;
@@ -122,8 +129,7 @@ static int stm32_count_function_set(struct counter_device *counter, 
		sms = 3;

		break;

	default:

		sms = 0;

		break;

		return -EINVAL;

	}



	/* Store enable status */
@@ -274,31 +280,36 @@ static int stm32_action_get(struct counter_device *counter, 
	size_t function;

	int err;



	/* Default action mode (e.g. STM32_COUNT_SLAVE_MODE_DISABLED) */

	*action = STM32_SYNAPSE_ACTION_NONE;



	err = stm32_count_function_get(counter, count, &function);

	if (err)

		return 0;

		return err;



	switch (function) {

	case STM32_COUNT_SLAVE_MODE_DISABLED:

		/* counts on internal clock when CEN=1 */

		*action = STM32_SYNAPSE_ACTION_NONE;

		return 0;

	case STM32_COUNT_ENCODER_MODE_1:

		/* counts up/down on TI1FP1 edge depending on TI2FP2 level */

		if (synapse->signal->id == count->synapses[0].signal->id)

			*action = STM32_SYNAPSE_ACTION_BOTH_EDGES;

		break;

		else

			*action = STM32_SYNAPSE_ACTION_NONE;

		return 0;

	case STM32_COUNT_ENCODER_MODE_2:

		/* counts up/down on TI2FP2 edge depending on TI1FP1 level */

		if (synapse->signal->id == count->synapses[1].signal->id)

			*action = STM32_SYNAPSE_ACTION_BOTH_EDGES;

		break;

		else

			*action = STM32_SYNAPSE_ACTION_NONE;

		return 0;

	case STM32_COUNT_ENCODER_MODE_3:

		/* counts up/down on both TI1FP1 and TI2FP2 edges */

		*action = STM32_SYNAPSE_ACTION_BOTH_EDGES;

		break;

	}



		return 0;

	default:

		return -EINVAL;

	}

}



static const struct counter_ops stm32_timer_cnt_ops = {