linux/drivers/gpu/drm/msm/dp/dp_aux.c

// SPDX-License-Identifier: GPL-2.0-only
/*
 * Copyright (c) 2012-2020, The Linux Foundation. All rights reserved.
 */

#include <linux/delay.h>
#include <linux/phy/phy.h>
#include <drm/drm_print.h>

#include "dp_reg.h"
#include "dp_aux.h"

enum msm_dp_aux_err { … };

struct dp_aux_private { … };

#define MAX_AUX_RETRIES …

static ssize_t dp_aux_write(struct dp_aux_private *aux,
			struct drm_dp_aux_msg *msg)
{ … }

static ssize_t dp_aux_cmd_fifo_tx(struct dp_aux_private *aux,
			      struct drm_dp_aux_msg *msg)
{ … }

static ssize_t dp_aux_cmd_fifo_rx(struct dp_aux_private *aux,
		struct drm_dp_aux_msg *msg)
{ … }

static void dp_aux_update_offset_and_segment(struct dp_aux_private *aux,
					     struct drm_dp_aux_msg *input_msg)
{ … }

/**
 * dp_aux_transfer_helper() - helper function for EDID read transactions
 *
 * @aux: DP AUX private structure
 * @input_msg: input message from DRM upstream APIs
 * @send_seg: send the segment to sink
 *
 * return: void
 *
 * This helper function is used to fix EDID reads for non-compliant
 * sinks that do not handle the i2c middle-of-transaction flag correctly.
 */
static void dp_aux_transfer_helper(struct dp_aux_private *aux,
				   struct drm_dp_aux_msg *input_msg,
				   bool send_seg)
{ … }

/*
 * This function does the real job to process an AUX transaction.
 * It will call aux_reset() function to reset the AUX channel,
 * if the waiting is timeout.
 */
static ssize_t dp_aux_transfer(struct drm_dp_aux *dp_aux,
			       struct drm_dp_aux_msg *msg)
{ … }

irqreturn_t dp_aux_isr(struct drm_dp_aux *dp_aux)
{ … }

void dp_aux_enable_xfers(struct drm_dp_aux *dp_aux, bool enabled)
{ … }

void dp_aux_reconfig(struct drm_dp_aux *dp_aux)
{ … }

void dp_aux_init(struct drm_dp_aux *dp_aux)
{ … }

void dp_aux_deinit(struct drm_dp_aux *dp_aux)
{ … }

int dp_aux_register(struct drm_dp_aux *dp_aux)
{ … }

void dp_aux_unregister(struct drm_dp_aux *dp_aux)
{ … }

static int dp_wait_hpd_asserted(struct drm_dp_aux *dp_aux,
				 unsigned long wait_us)
{ … }

struct drm_dp_aux *dp_aux_get(struct device *dev, struct dp_catalog *catalog,
			      struct phy *phy,
			      bool is_edp)
{ … }

void dp_aux_put(struct drm_dp_aux *dp_aux)
{ … }