source: mainline/uspace/lib/usbdev/src/devpoll.c@ 7dddd7b

/*
 * Copyright (c) 2011 Vojtech Horky
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * - Redistributions of source code must retain the above copyright
 *   notice, this list of conditions and the following disclaimer.
 * - Redistributions in binary form must reproduce the above copyright
 *   notice, this list of conditions and the following disclaimer in the
 *   documentation and/or other materials provided with the distribution.
 * - The name of the author may not be used to endorse or promote products
 *   derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

/** @addtogroup libusbdev
 * @{
 */
/** @file
 * USB device driver framework - automatic interrupt polling.
 */

#include <usb/dev/device.h>
#include <usb/dev/pipes.h>
#include <usb/dev/poll.h>
#include <usb/dev/request.h>
#include <usb/classes/classes.h>
#include <usb/debug.h>
#include <usb/descriptor.h>
#include <usb/usb.h>

#include <assert.h>
#include <async.h>
#include <errno.h>
#include <fibril.h>
#include <stdbool.h>
#include <stdlib.h>
#include <str_error.h>
#include <stddef.h>
#include <stdint.h>

/** Maximum number of failed consecutive requests before announcing failure. */
#define MAX_FAILED_ATTEMPTS 3

/** Data needed for polling. */
typedef struct {
        /** Parameters for automated polling. */
        usb_device_auto_polling_t auto_polling;

        /** USB device to poll. */
        usb_device_t *dev;
        /** Device enpoint mapping to use for polling. */
        usb_endpoint_mapping_t *polling_mapping;
        /** Size of the recieved data. */
        size_t request_size;
        /** Data buffer. */
        uint8_t *buffer;
} polling_data_t;


/** Polling fibril.
 *
 * @param arg Pointer to polling_data_t.
 * @return Always EOK.
 */
static int polling_fibril(void *arg)
{
        assert(arg);
        const polling_data_t *data = arg;
        /* Helper to reduce typing. */
        const usb_device_auto_polling_t *params = &data->auto_polling;

        usb_pipe_t *pipe = &data->polling_mapping->pipe;

        if (params->debug > 0) {
                const usb_endpoint_mapping_t *mapping =
                    data->polling_mapping;
                usb_log_debug("Poll (%p): started polling of `%s' - " \
                    "interface %d (%s,%d,%d), %zuB/%zu.\n",
                    data, usb_device_get_name(data->dev),
                    (int) mapping->interface->interface_number,
                    usb_str_class(mapping->interface->interface_class),
                    (int) mapping->interface->interface_subclass,
                    (int) mapping->interface->interface_protocol,
                    data->request_size, pipe->desc.max_transfer_size);
        }

        size_t failed_attempts = 0;
        while (failed_attempts <= params->max_failures) {
                size_t actual_size;
                const int rc = usb_pipe_read(pipe, data->buffer,
                    data->request_size, &actual_size);

                if (rc == EOK) {
                        if (params->debug > 1) {
                                usb_log_debug(
                                    "Poll%p: received: '%s' (%zuB).\n",
                                    data,
                                    usb_debug_str_buffer(data->buffer,
                                        actual_size, 16),
                                    actual_size);
                        }
                } else {
                                usb_log_debug(
                                    "Poll%p: polling failed: %s.\n",
                                    data, str_error(rc));
                }

                /* If the pipe stalled, we can try to reset the stall. */
                if ((rc == ESTALL) && (params->auto_clear_halt)) {
                        /*
                         * We ignore error here as this is usually a futile
                         * attempt anyway.
                         */
                        usb_request_clear_endpoint_halt(
                            usb_device_get_default_pipe(data->dev),
                            pipe->desc.endpoint_no);
                }

                if (rc != EOK) {
                        ++failed_attempts;
                        const bool cont = (params->on_error == NULL) ? true :
                            params->on_error(data->dev, rc, params->arg);
                        if (!cont) {
                                /* This is user requested abort, erases failures. */
                                failed_attempts = 0;
                                break;
                        }
                        continue;
                }

                /* We have the data, execute the callback now. */
                assert(params->on_data);
                const bool carry_on = params->on_data(
                    data->dev, data->buffer, actual_size, params->arg);

                if (!carry_on) {
                        /* This is user requested abort, erases failures. */
                        failed_attempts = 0;
                        break;
                }

                /* Reset as something might be only a temporary problem. */
                failed_attempts = 0;

                /* Take a rest before next request. */

                // FIXME TODO: This is broken, the time is in ms not us.
                // but first we need to fix drivers to actually stop using this,
                // since polling delay should be implemented in HC schedule
                async_usleep(params->delay);
        }

        const bool failed = failed_attempts > 0;

        if (params->on_polling_end != NULL) {
                params->on_polling_end(data->dev, failed, params->arg);
        }

        if (params->debug > 0) {
                if (failed) {
                        usb_log_error("Polling of device `%s' terminated: "
                            "recurring failures.\n",
                            usb_device_get_name(data->dev));
                } else {
                        usb_log_debug("Polling of device `%s' terminated: "
                            "driver request.\n",
                            usb_device_get_name(data->dev));
                }
        }

        /* Free the allocated memory. */
        free(data->buffer);
        free(data);

        return EOK;
}


/** Start automatic device polling over interrupt in pipe.
 *
 * The polling settings is copied thus it is okay to destroy the structure
 * after this function returns.
 *
 * @warning There is no guarantee when the request to the device
 * will be sent for the first time (it is possible that this
 * first request would be executed prior to return from this function).
 *
 * @param dev Device to be periodically polled.
 * @param epm Endpoint mapping to use.
 * @param polling Polling settings.
 * @param req_size How many bytes to ask for in each request.
 * @return Error code.
 * @retval EOK New fibril polling the device was already started.
 */
int usb_device_auto_polling(usb_device_t *dev, usb_endpoint_mapping_t *epm,
    const usb_device_auto_polling_t *polling, size_t req_size)
{
        int rc;
        if (!dev || !polling || !polling->on_data)
                return EBADMEM;

        if (!req_size)
                return EINVAL;

        if (!epm || (epm->pipe.desc.transfer_type != USB_TRANSFER_INTERRUPT) ||
            (epm->pipe.desc.direction != USB_DIRECTION_IN))
                return EINVAL;

        polling_data_t *polling_data = malloc(sizeof(polling_data_t));
        if (!polling_data)
                return ENOMEM;

        /* Fill-in the data. */
        polling_data->buffer = malloc(req_size);
        if (polling_data->buffer == NULL) {
                rc = ENOMEM;
                goto err_polling_data;
        }
        polling_data->request_size = req_size;
        polling_data->dev = dev;
        polling_data->polling_mapping = epm;

        /* Copy provided settings. */
        polling_data->auto_polling = *polling;

        /* Negative value means use descriptor provided value. */
        if (polling->delay < 0) {
                polling_data->auto_polling.delay =
                    epm->descriptor->poll_interval;
        }

        fid_t fibril = fibril_create(polling_fibril, polling_data);
        if (!fibril) {
                rc = ENOMEM;
                goto err_buffer;
        }
        fibril_add_ready(fibril);

        /* Fibril launched. That fibril will free the allocated data. */
        return EOK;

err_buffer:
        free(polling_data->buffer);
err_polling_data:
        free(polling_data);
        return rc;
}

/**
 * @}
 */