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Diffstat (limited to 'atmel-samd/asf4/samd21/hal/utils/src/utils_event.c')
| -rw-r--r-- | atmel-samd/asf4/samd21/hal/utils/src/utils_event.c | 135 |
1 files changed, 135 insertions, 0 deletions
diff --git a/atmel-samd/asf4/samd21/hal/utils/src/utils_event.c b/atmel-samd/asf4/samd21/hal/utils/src/utils_event.c new file mode 100644 index 000000000..ab4e9eb3f --- /dev/null +++ b/atmel-samd/asf4/samd21/hal/utils/src/utils_event.c @@ -0,0 +1,135 @@ +/** + * \file + * + * \brief Events implementation. + * + * Copyright (C) 2015 Atmel Corporation. All rights reserved. + * + * \asf_license_start + * + * \page License + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions are met: + * + * 1. Redistributions of source code must retain the above copyright notice, + * this list of conditions and the following disclaimer. + * + * 2. 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. + * + * 3. The name of Atmel may not be used to endorse or promote products derived + * from this software without specific prior written permission. + * + * 4. This software may only be redistributed and used in connection with an + * Atmel microcontroller product. + * + * THIS SOFTWARE IS PROVIDED BY ATMEL "AS IS" AND ANY EXPRESS OR IMPLIED + * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF + * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT ARE + * EXPRESSLY AND SPECIFICALLY DISCLAIMED. IN NO EVENT SHALL ATMEL 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 CAUSEsD 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. + * + * \asf_license_stop + * + */ + +#include <utils_event.h> +#include <utils_assert.h> +#include <string.h> + +#define EVENT_WORD_BITS (sizeof(event_word_t) * 8) + +static struct list_descriptor events; +static uint8_t subscribed[EVENT_MASK_SIZE]; + +int32_t event_subscribe(struct event *const event, const event_id_t id, event_cb_t cb) +{ + /* get byte and bit number of the given event in the event mask */ + const uint8_t position = id >> 3; + const uint8_t mask = 1 << (id & 0x7); + + ASSERT(event && cb && (id < EVENT_MAX_AMOUNT)); + + if (event->mask[position] & mask) { + return ERR_NO_CHANGE; /* Already subscribed */ + } + + if (!is_list_element(&events, event)) { + memset(event->mask, 0, EVENT_MASK_SIZE); + list_insert_as_head(&events, event); + } + event->cb = cb; + event->mask[position] |= mask; + + subscribed[position] |= mask; + + return ERR_NONE; +} + +int32_t event_unsubscribe(struct event *const event, const event_id_t id) +{ + /* get byte and bit number of the given event in the event mask */ + const uint8_t position = id >> 3; + const uint8_t mask = 1 << (id & 0x7); + const struct event *current; + uint8_t i; + + ASSERT(event && (id < EVENT_MAX_AMOUNT)); + + if (!(event->mask[position] & mask)) { + return ERR_NO_CHANGE; /* Already unsubscribed */ + } + + event->mask[position] &= ~mask; + + /* Check if there are more subscribers */ + for ((current = (const struct event *)list_get_head(&events)); current; + current = (const struct event *)list_get_next_element(current)) { + if (current->mask[position] & mask) { + break; + } + } + if (!current) { + subscribed[position] &= ~mask; + } + + /* Remove event from the list. Can be unsave, document it! */ + for (i = 0; i < ARRAY_SIZE(event->mask); i++) { + if (event->mask[i]) { + return ERR_NONE; + } + } + list_delete_element(&events, event); + + return ERR_NONE; +} + +void event_post(const event_id_t id, const event_data_t data) +{ + /* get byte and bit number of the given event in the event mask */ + const uint8_t position = id >> 3; + const uint8_t mask = 1 << (id & 0x7); + const struct event *current; + + ASSERT((id < EVENT_MAX_AMOUNT)); + + if (!(subscribed[position] & mask)) { + return; /* No subscribers */ + } + + /* Find all subscribers */ + for ((current = (const struct event *)list_get_head(&events)); current; + current = (const struct event *)list_get_next_element(current)) { + if (current->mask[position] & mask) { + current->cb(id, data); + } + } +} |