hif/src/dispatcher/multibus.c

/*
 * Copyright (c) 2016 The Linux Foundation. All rights reserved.
 *
 * Previously licensed under the ISC license by Qualcomm Atheros, Inc.
 *
 *
 * Permission to use, copy, modify, and/or distribute this software for
 * any purpose with or without fee is hereby granted, provided that the
 * above copyright notice and this permission notice appear in all
 * copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL
 * WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE
 * AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
 * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
 * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
 * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
 * PERFORMANCE OF THIS SOFTWARE.
 */

/*
 * This file was originally distributed by Qualcomm Atheros, Inc.
 * under proprietary terms before Copyright ownership was assigned
 * to the Linux Foundation.
 */


/* this file dispatches functions to bus specific definitions */
#include "hif_debug.h"
#include "hif.h"
#include "hif_main.h"
#include "multibus.h"

/**
 * hif_intialize_default_ops() - intializes default operations values
 *
 * bus specific features should assign their dummy implementations here.
 */
static void hif_intialize_default_ops(struct hif_softc *hif_sc)
{
	struct hif_bus_ops *bus_ops = &hif_sc->bus_ops;

	/* must be filled in by hif_bus_open */
	bus_ops->hif_bus_close = NULL;

	/* dummy implementations */
}

#define NUM_OPS (sizeof(struct hif_bus_ops) / sizeof(void *))

/**
 * hif_verify_basic_ops() - ensure required bus apis are defined
 *
 * all bus operations must be defined to avoid crashes
 * itterate over the structure and ensure all function pointers
 * are non null.
 *
 * Return: QDF_STATUS_SUCCESS if all the operations are defined
 */
static QDF_STATUS hif_verify_basic_ops(struct hif_softc *hif_sc)
{
	struct hif_bus_ops *bus_ops = &hif_sc->bus_ops;
	void **ops_array = (void *)bus_ops;
	QDF_STATUS status = QDF_STATUS_SUCCESS;
	int i;

	for (i = 0; i < NUM_OPS; i++) {
		if (!ops_array[i]) {
			HIF_ERROR("%s: function %d is null", __func__, i);
			status = QDF_STATUS_E_NOSUPPORT;
		}
	}
	return status;
}

/**
 * hif_bus_open() - initialize the bus_ops and call the bus specific open
 * hif_sc: hif_context
 * bus_type: type of bus being enumerated
 *
 * Return: QDF_STATUS_SUCCESS or error
 */
QDF_STATUS hif_bus_open(struct hif_softc *hif_sc,
			enum qdf_bus_type bus_type)
{
	QDF_STATUS status = QDF_STATUS_E_INVAL;

	hif_intialize_default_ops(hif_sc);

	switch (bus_type) {
	case QDF_BUS_TYPE_PCI:
		status = hif_initialize_pci_ops(&hif_sc->bus_ops);
		break;
	case QDF_BUS_TYPE_SNOC:
		status = hif_initialize_snoc_ops(&hif_sc->bus_ops);
		break;
	default:
		status = QDF_STATUS_E_NOSUPPORT;
		break;
	}

	if (status != QDF_STATUS_SUCCESS) {
		HIF_ERROR("%s: %d not supported", __func__, bus_type);
		return status;
	}

	status = hif_verify_basic_ops(hif_sc);
	if (status != QDF_STATUS_SUCCESS)
		return status;

	return hif_sc->bus_ops.hif_bus_open(hif_sc, bus_type);
}

/**
 * hif_bus_close() - close the bus
 * @hif_sc: hif_context
 */
void hif_bus_close(struct hif_softc *hif_sc)
{
	hif_sc->bus_ops.hif_bus_close(hif_sc);
}