xref: /openbmc/linux/drivers/media/pci/cx18/cx18-irq.c (revision 22b6e7f3)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  *  cx18 interrupt handling
4  *
5  *  Copyright (C) 2007  Hans Verkuil <hverkuil@xs4all.nl>
6  *  Copyright (C) 2008  Andy Walls <awalls@md.metrocast.net>
7  */
8 
9 #include "cx18-driver.h"
10 #include "cx18-io.h"
11 #include "cx18-irq.h"
12 #include "cx18-mailbox.h"
13 #include "cx18-scb.h"
14 
15 static void xpu_ack(struct cx18 *cx, u32 sw2)
16 {
17 	if (sw2 & IRQ_CPU_TO_EPU_ACK)
18 		wake_up(&cx->mb_cpu_waitq);
19 	if (sw2 & IRQ_APU_TO_EPU_ACK)
20 		wake_up(&cx->mb_apu_waitq);
21 }
22 
23 static void epu_cmd(struct cx18 *cx, u32 sw1)
24 {
25 	if (sw1 & IRQ_CPU_TO_EPU)
26 		cx18_api_epu_cmd_irq(cx, CPU);
27 	if (sw1 & IRQ_APU_TO_EPU)
28 		cx18_api_epu_cmd_irq(cx, APU);
29 }
30 
31 irqreturn_t cx18_irq_handler(int irq, void *dev_id)
32 {
33 	struct cx18 *cx = dev_id;
34 	u32 sw1, sw2, hw2;
35 
36 	sw1 = cx18_read_reg(cx, SW1_INT_STATUS) & cx->sw1_irq_mask;
37 	sw2 = cx18_read_reg(cx, SW2_INT_STATUS) & cx->sw2_irq_mask;
38 	hw2 = cx18_read_reg(cx, HW2_INT_CLR_STATUS) & cx->hw2_irq_mask;
39 
40 	if (sw1)
41 		cx18_write_reg_expect(cx, sw1, SW1_INT_STATUS, ~sw1, sw1);
42 	if (sw2)
43 		cx18_write_reg_expect(cx, sw2, SW2_INT_STATUS, ~sw2, sw2);
44 	if (hw2)
45 		cx18_write_reg_expect(cx, hw2, HW2_INT_CLR_STATUS, ~hw2, hw2);
46 
47 	if (sw1 || sw2 || hw2)
48 		CX18_DEBUG_HI_IRQ("received interrupts SW1: %x	SW2: %x  HW2: %x\n",
49 				  sw1, sw2, hw2);
50 
51 	/*
52 	 * SW1 responses have to happen first.  The sending XPU times out the
53 	 * incoming mailboxes on us rather rapidly.
54 	 */
55 	if (sw1)
56 		epu_cmd(cx, sw1);
57 
58 	/* To do: interrupt-based I2C handling
59 	if (hw2 & (HW2_I2C1_INT|HW2_I2C2_INT)) {
60 	}
61 	*/
62 
63 	if (sw2)
64 		xpu_ack(cx, sw2);
65 
66 	return (sw1 || sw2 || hw2) ? IRQ_HANDLED : IRQ_NONE;
67 }
68