xref: /linux/drivers/staging/media/atomisp/pci/runtime/eventq/src/eventq.c (revision 4b4193256c8d3bc3a5397b5cd9494c2ad386317d)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Support for Intel Camera Imaging ISP subsystem.
4  * Copyright (c) 2015, Intel Corporation.
5  *
6  * This program is free software; you can redistribute it and/or modify it
7  * under the terms and conditions of the GNU General Public License,
8  * version 2, as published by the Free Software Foundation.
9  *
10  * This program is distributed in the hope it will be useful, but WITHOUT
11  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
13  * more details.
14  */
15 
16 #include "ia_css_types.h"
17 #include "assert_support.h"
18 #include "ia_css_queue.h" /* sp2host_dequeue_irq_event() */
19 #include "ia_css_eventq.h"
20 #include "ia_css_event.h"	/* ia_css_event_encode()
21 				ia_css_event_decode()
22 				*/
ia_css_eventq_recv(ia_css_queue_t * eventq_handle,uint8_t * payload)23 int ia_css_eventq_recv(
24     ia_css_queue_t *eventq_handle,
25     uint8_t *payload)
26 {
27 	u32 sp_event;
28 	int error;
29 
30 	/* dequeue the IRQ event */
31 	error = ia_css_queue_dequeue(eventq_handle, &sp_event);
32 
33 	/* check whether the IRQ event is available or not */
34 	if (!error)
35 		ia_css_event_decode(sp_event, payload);
36 	return error;
37 }
38 
39 /*
40  * @brief The Host sends the event to the SP.
41  * Refer to "sh_css_sp.h" for details.
42  */
ia_css_eventq_send(ia_css_queue_t * eventq_handle,u8 evt_id,u8 evt_payload_0,u8 evt_payload_1,uint8_t evt_payload_2)43 int ia_css_eventq_send(
44     ia_css_queue_t *eventq_handle,
45     u8 evt_id,
46     u8 evt_payload_0,
47     u8 evt_payload_1,
48     uint8_t evt_payload_2)
49 {
50 	u8 tmp[4];
51 	u32 sw_event;
52 	int error = -ENOSYS;
53 
54 	/*
55 	 * Encode the queue type, the thread ID and
56 	 * the queue ID into the event.
57 	 */
58 	tmp[0] = evt_id;
59 	tmp[1] = evt_payload_0;
60 	tmp[2] = evt_payload_1;
61 	tmp[3] = evt_payload_2;
62 	ia_css_event_encode(tmp, 4, &sw_event);
63 
64 	/* queue the software event (busy-waiting) */
65 	for ( ; ; ) {
66 		error = ia_css_queue_enqueue(eventq_handle, sw_event);
67 		if (error != -ENOBUFS) {
68 			/* We were able to successfully send the event
69 			   or had a real failure. return the status*/
70 			break;
71 		}
72 		/* Wait for the queue to be not full and try again*/
73 		udelay(1);
74 	}
75 	return error;
76 }
77