Commit c2a75666 authored by David Lechner's avatar David Lechner Committed by William Breathitt Gray
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counter: ti-eqep: add direction support 



Add support for reading the direction and for emitting direction change
events to the ti-eqep counter driver.

Signed-off-by: default avatarDavid Lechner <dlechner@baylibre.com>
Link: https://lore.kernel.org/r/20250110-counter-ti-eqep-add-direction-support-v2-4-c6b6f96d2db9@baylibre.com


Signed-off-by: default avatarWilliam Breathitt Gray <wbg@kernel.org>
parent 37f7a388

drivers/counter/ti-eqep.c

+32 −0
Original line number Diff line number Diff line
@@ -107,6 +107,15 @@ 
#define QCLR_PCE		BIT(1)

#define QCLR_INT		BIT(0)



#define QEPSTS_UPEVNT		BIT(7)

#define QEPSTS_FDF		BIT(6)

#define QEPSTS_QDF		BIT(5)

#define QEPSTS_QDLF		BIT(4)

#define QEPSTS_COEF		BIT(3)

#define QEPSTS_CDEF		BIT(2)

#define QEPSTS_FIMF		BIT(1)

#define QEPSTS_PCEF		BIT(0)



/* EQEP Inputs */

enum {

	TI_EQEP_SIGNAL_QEPA,	/* QEPA/XCLK */
@@ -286,6 +295,9 @@ static int ti_eqep_events_configure(struct counter_device *counter) 
		case COUNTER_EVENT_UNDERFLOW:

			qeint |= QEINT_PCU;

			break;

		case COUNTER_EVENT_DIRECTION_CHANGE:

			qeint |= QEINT_QDC;

			break;

		}

	}
@@ -298,6 +310,7 @@ static int ti_eqep_watch_validate(struct counter_device *counter, 
	switch (watch->event) {

	case COUNTER_EVENT_OVERFLOW:

	case COUNTER_EVENT_UNDERFLOW:

	case COUNTER_EVENT_DIRECTION_CHANGE:

		if (watch->channel != 0)

			return -EINVAL;
@@ -368,11 +381,27 @@ static int ti_eqep_position_enable_write(struct counter_device *counter, 
	return 0;

}



static int ti_eqep_direction_read(struct counter_device *counter,

				  struct counter_count *count,

				  enum counter_count_direction *direction)

{

	struct ti_eqep_cnt *priv = counter_priv(counter);

	u32 qepsts;



	regmap_read(priv->regmap16, QEPSTS, &qepsts);



	*direction = (qepsts & QEPSTS_QDF) ? COUNTER_COUNT_DIRECTION_FORWARD

					   : COUNTER_COUNT_DIRECTION_BACKWARD;



	return 0;

}



static struct counter_comp ti_eqep_position_ext[] = {

	COUNTER_COMP_CEILING(ti_eqep_position_ceiling_read,

			     ti_eqep_position_ceiling_write),

	COUNTER_COMP_ENABLE(ti_eqep_position_enable_read,

			    ti_eqep_position_enable_write),

	COUNTER_COMP_DIRECTION(ti_eqep_direction_read),

};



static struct counter_signal ti_eqep_signals[] = {
@@ -439,6 +468,9 @@ static irqreturn_t ti_eqep_irq_handler(int irq, void *dev_id) 
	if (qflg & QFLG_PCU)

		counter_push_event(counter, COUNTER_EVENT_UNDERFLOW, 0);



	if (qflg & QFLG_QDC)

		counter_push_event(counter, COUNTER_EVENT_DIRECTION_CHANGE, 0);



	regmap_write(priv->regmap16, QCLR, qflg);



	return IRQ_HANDLED;