Commit 2425dee8 authored by Sean Anderson's avatar Sean Anderson Committed by Tomi Valkeinen
Browse files

drm: zynqmp_dp: Use AUX IRQs instead of polling 



Instead of polling the status register for the AUX status, just enable
the IRQs and signal a completion.

Signed-off-by: default avatarSean Anderson <sean.anderson@linux.dev>
Signed-off-by: default avatarTomi Valkeinen <tomi.valkeinen@ideasonboard.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240809193600.3360015-6-sean.anderson@linux.dev
parent 948a944e

drivers/gpu/drm/xlnx/zynqmp_dp.c

+25 −10
Original line number Diff line number Diff line
@@ -286,6 +286,7 @@ struct zynqmp_dp_config { 
 * @next_bridge: The downstream bridge

 * @config: IP core configuration from DTS

 * @aux: aux channel

 * @aux_done: Completed when we get an AUX reply or timeout

 * @phy: PHY handles for DP lanes

 * @num_lanes: number of enabled phy lanes

 * @hpd_work: hot plug detection worker
@@ -306,6 +307,7 @@ struct zynqmp_dp { 
	struct drm_bridge bridge;

	struct work_struct hpd_work;

	struct work_struct hpd_irq_work;

	struct completion aux_done;

	struct mutex lock;



	struct drm_bridge *next_bridge;
@@ -942,12 +944,15 @@ static int zynqmp_dp_aux_cmd_submit(struct zynqmp_dp *dp, u32 cmd, u16 addr, 
				    u8 *buf, u8 bytes, u8 *reply)

{

	bool is_read = (cmd & AUX_READ_BIT) ? true : false;

	unsigned long time_left;

	u32 reg, i;



	reg = zynqmp_dp_read(dp, ZYNQMP_DP_INTERRUPT_SIGNAL_STATE);

	if (reg & ZYNQMP_DP_INTERRUPT_SIGNAL_STATE_REQUEST)

		return -EBUSY;



	reinit_completion(&dp->aux_done);



	zynqmp_dp_write(dp, ZYNQMP_DP_AUX_ADDRESS, addr);

	if (!is_read)

		for (i = 0; i < bytes; i++)
@@ -962,17 +967,14 @@ static int zynqmp_dp_aux_cmd_submit(struct zynqmp_dp *dp, u32 cmd, u16 addr, 
	zynqmp_dp_write(dp, ZYNQMP_DP_AUX_COMMAND, reg);



	/* Wait for reply to be delivered upto 2ms */

	for (i = 0; ; i++) {

		reg = zynqmp_dp_read(dp, ZYNQMP_DP_INTERRUPT_SIGNAL_STATE);

		if (reg & ZYNQMP_DP_INTERRUPT_SIGNAL_STATE_REPLY)

			break;



		if (reg & ZYNQMP_DP_INTERRUPT_SIGNAL_STATE_REPLY_TIMEOUT ||

		    i == 2)

	time_left = wait_for_completion_timeout(&dp->aux_done,

						msecs_to_jiffies(2));

	if (!time_left)

		return -ETIMEDOUT;



		usleep_range(1000, 1100);

	}

	reg = zynqmp_dp_read(dp, ZYNQMP_DP_INTERRUPT_SIGNAL_STATE);

	if (reg & ZYNQMP_DP_INTERRUPT_SIGNAL_STATE_REPLY_TIMEOUT)

		return -ETIMEDOUT;



	reg = zynqmp_dp_read(dp, ZYNQMP_DP_AUX_REPLY_CODE);

	if (reply)
@@ -1056,6 +1058,9 @@ static int zynqmp_dp_aux_init(struct zynqmp_dp *dp) 
			(w << ZYNQMP_DP_AUX_CLK_DIVIDER_AUX_FILTER_SHIFT) |

			(rate / (1000 * 1000)));



	zynqmp_dp_write(dp, ZYNQMP_DP_INT_EN, ZYNQMP_DP_INT_REPLY_RECEIVED |

					      ZYNQMP_DP_INT_REPLY_TIMEOUT);



	dp->aux.name = "ZynqMP DP AUX";

	dp->aux.dev = dp->dev;

	dp->aux.drm_dev = dp->bridge.dev;
@@ -1073,6 +1078,9 @@ static int zynqmp_dp_aux_init(struct zynqmp_dp *dp) 
static void zynqmp_dp_aux_cleanup(struct zynqmp_dp *dp)

{

	drm_dp_aux_unregister(&dp->aux);



	zynqmp_dp_write(dp, ZYNQMP_DP_INT_DS, ZYNQMP_DP_INT_REPLY_RECEIVED |

					      ZYNQMP_DP_INT_REPLY_TIMEOUT);

}



/* -----------------------------------------------------------------------------
@@ -1730,6 +1738,12 @@ static irqreturn_t zynqmp_dp_irq_handler(int irq, void *data) 
	if (status & ZYNQMP_DP_INT_HPD_IRQ)

		schedule_work(&dp->hpd_irq_work);



	if (status & ZYNQMP_DP_INTERRUPT_SIGNAL_STATE_REPLY)

		complete(&dp->aux_done);



	if (status & ZYNQMP_DP_INTERRUPT_SIGNAL_STATE_REPLY_TIMEOUT)

		complete(&dp->aux_done);



	return IRQ_HANDLED;

}
@@ -1753,6 +1767,7 @@ int zynqmp_dp_probe(struct zynqmp_dpsub *dpsub) 
	dp->dpsub = dpsub;

	dp->status = connector_status_disconnected;

	mutex_init(&dp->lock);

	init_completion(&dp->aux_done);



	INIT_WORK(&dp->hpd_work, zynqmp_dp_hpd_work_func);

	INIT_WORK(&dp->hpd_irq_work, zynqmp_dp_hpd_irq_work_func);