xref: /openbmc/linux/drivers/media/pci/cx18/cx18-irq.c (revision 8730046c)
1 /*
2  *  cx18 interrupt handling
3  *
4  *  Copyright (C) 2007  Hans Verkuil <hverkuil@xs4all.nl>
5  *  Copyright (C) 2008  Andy Walls <awalls@md.metrocast.net>
6  *
7  *  This program is free software; you can redistribute it and/or modify
8  *  it under the terms of the GNU General Public License as published by
9  *  the Free Software Foundation; either version 2 of the License, or
10  *  (at your option) any later version.
11  *
12  *  This program is distributed in the hope that it will be useful,
13  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
14  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15  *  GNU General Public License for more details.
16  *
17  *  You should have received a copy of the GNU General Public License
18  *  along with this program; if not, write to the Free Software
19  *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
20  *  02111-1307  USA
21  */
22 
23 #include "cx18-driver.h"
24 #include "cx18-io.h"
25 #include "cx18-irq.h"
26 #include "cx18-mailbox.h"
27 #include "cx18-scb.h"
28 
29 static void xpu_ack(struct cx18 *cx, u32 sw2)
30 {
31 	if (sw2 & IRQ_CPU_TO_EPU_ACK)
32 		wake_up(&cx->mb_cpu_waitq);
33 	if (sw2 & IRQ_APU_TO_EPU_ACK)
34 		wake_up(&cx->mb_apu_waitq);
35 }
36 
37 static void epu_cmd(struct cx18 *cx, u32 sw1)
38 {
39 	if (sw1 & IRQ_CPU_TO_EPU)
40 		cx18_api_epu_cmd_irq(cx, CPU);
41 	if (sw1 & IRQ_APU_TO_EPU)
42 		cx18_api_epu_cmd_irq(cx, APU);
43 }
44 
45 irqreturn_t cx18_irq_handler(int irq, void *dev_id)
46 {
47 	struct cx18 *cx = (struct cx18 *)dev_id;
48 	u32 sw1, sw2, hw2;
49 
50 	sw1 = cx18_read_reg(cx, SW1_INT_STATUS) & cx->sw1_irq_mask;
51 	sw2 = cx18_read_reg(cx, SW2_INT_STATUS) & cx->sw2_irq_mask;
52 	hw2 = cx18_read_reg(cx, HW2_INT_CLR_STATUS) & cx->hw2_irq_mask;
53 
54 	if (sw1)
55 		cx18_write_reg_expect(cx, sw1, SW1_INT_STATUS, ~sw1, sw1);
56 	if (sw2)
57 		cx18_write_reg_expect(cx, sw2, SW2_INT_STATUS, ~sw2, sw2);
58 	if (hw2)
59 		cx18_write_reg_expect(cx, hw2, HW2_INT_CLR_STATUS, ~hw2, hw2);
60 
61 	if (sw1 || sw2 || hw2)
62 		CX18_DEBUG_HI_IRQ("received interrupts SW1: %x	SW2: %x  HW2: %x\n",
63 				  sw1, sw2, hw2);
64 
65 	/*
66 	 * SW1 responses have to happen first.  The sending XPU times out the
67 	 * incoming mailboxes on us rather rapidly.
68 	 */
69 	if (sw1)
70 		epu_cmd(cx, sw1);
71 
72 	/* To do: interrupt-based I2C handling
73 	if (hw2 & (HW2_I2C1_INT|HW2_I2C2_INT)) {
74 	}
75 	*/
76 
77 	if (sw2)
78 		xpu_ack(cx, sw2);
79 
80 	return (sw1 || sw2 || hw2) ? IRQ_HANDLED : IRQ_NONE;
81 }
82