xref: /openbmc/linux/drivers/media/pci/cx18/cx18-irq.c (revision 4f6cce39)
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 
18 #include "cx18-driver.h"
19 #include "cx18-io.h"
20 #include "cx18-irq.h"
21 #include "cx18-mailbox.h"
22 #include "cx18-scb.h"
23 
24 static void xpu_ack(struct cx18 *cx, u32 sw2)
25 {
26 	if (sw2 & IRQ_CPU_TO_EPU_ACK)
27 		wake_up(&cx->mb_cpu_waitq);
28 	if (sw2 & IRQ_APU_TO_EPU_ACK)
29 		wake_up(&cx->mb_apu_waitq);
30 }
31 
32 static void epu_cmd(struct cx18 *cx, u32 sw1)
33 {
34 	if (sw1 & IRQ_CPU_TO_EPU)
35 		cx18_api_epu_cmd_irq(cx, CPU);
36 	if (sw1 & IRQ_APU_TO_EPU)
37 		cx18_api_epu_cmd_irq(cx, APU);
38 }
39 
40 irqreturn_t cx18_irq_handler(int irq, void *dev_id)
41 {
42 	struct cx18 *cx = (struct cx18 *)dev_id;
43 	u32 sw1, sw2, hw2;
44 
45 	sw1 = cx18_read_reg(cx, SW1_INT_STATUS) & cx->sw1_irq_mask;
46 	sw2 = cx18_read_reg(cx, SW2_INT_STATUS) & cx->sw2_irq_mask;
47 	hw2 = cx18_read_reg(cx, HW2_INT_CLR_STATUS) & cx->hw2_irq_mask;
48 
49 	if (sw1)
50 		cx18_write_reg_expect(cx, sw1, SW1_INT_STATUS, ~sw1, sw1);
51 	if (sw2)
52 		cx18_write_reg_expect(cx, sw2, SW2_INT_STATUS, ~sw2, sw2);
53 	if (hw2)
54 		cx18_write_reg_expect(cx, hw2, HW2_INT_CLR_STATUS, ~hw2, hw2);
55 
56 	if (sw1 || sw2 || hw2)
57 		CX18_DEBUG_HI_IRQ("received interrupts SW1: %x	SW2: %x  HW2: %x\n",
58 				  sw1, sw2, hw2);
59 
60 	/*
61 	 * SW1 responses have to happen first.  The sending XPU times out the
62 	 * incoming mailboxes on us rather rapidly.
63 	 */
64 	if (sw1)
65 		epu_cmd(cx, sw1);
66 
67 	/* To do: interrupt-based I2C handling
68 	if (hw2 & (HW2_I2C1_INT|HW2_I2C2_INT)) {
69 	}
70 	*/
71 
72 	if (sw2)
73 		xpu_ack(cx, sw2);
74 
75 	return (sw1 || sw2 || hw2) ? IRQ_HANDLED : IRQ_NONE;
76 }
77