1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * arch/sh/boards/renesas/r7780rp/psw.c
4  *
5  * push switch support for RDBRP-1/RDBREVRP-1 debug boards.
6  *
7  * Copyright (C) 2006  Paul Mundt
8  */
9 #include <linux/io.h>
10 #include <linux/module.h>
11 #include <linux/interrupt.h>
12 #include <linux/platform_device.h>
13 #include <mach/highlander.h>
14 #include <asm/push-switch.h>
15 
16 static irqreturn_t psw_irq_handler(int irq, void *arg)
17 {
18 	struct platform_device *pdev = arg;
19 	struct push_switch *psw = platform_get_drvdata(pdev);
20 	struct push_switch_platform_info *psw_info = pdev->dev.platform_data;
21 	unsigned int l, mask;
22 	int ret = 0;
23 
24 	l = __raw_readw(PA_DBSW);
25 
26 	/* Nothing to do if there's no state change */
27 	if (psw->state) {
28 		ret = 1;
29 		goto out;
30 	}
31 
32 	mask = l & 0x70;
33 	/* Figure out who raised it */
34 	if (mask & (1 << psw_info->bit)) {
35 		psw->state = !!(mask & (1 << psw_info->bit));
36 		if (psw->state)	/* debounce */
37 			mod_timer(&psw->debounce, jiffies + 50);
38 
39 		ret = 1;
40 	}
41 
42 out:
43 	/* Clear the switch IRQs */
44 	l |= (0x7 << 12);
45 	__raw_writew(l, PA_DBSW);
46 
47 	return IRQ_RETVAL(ret);
48 }
49 
50 static struct resource psw_resources[] = {
51 	[0] = {
52 		.start	= IRQ_PSW,
53 		.flags	= IORESOURCE_IRQ,
54 	},
55 };
56 
57 static struct push_switch_platform_info s2_platform_data = {
58 	.name		= "s2",
59 	.bit		= 6,
60 	.irq_flags	= IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING |
61 			  IRQF_SHARED,
62 	.irq_handler	= psw_irq_handler,
63 };
64 
65 static struct platform_device s2_switch_device = {
66 	.name		= "push-switch",
67 	.id		= 0,
68 	.num_resources	= ARRAY_SIZE(psw_resources),
69 	.resource	= psw_resources,
70 	.dev		= {
71 		.platform_data = &s2_platform_data,
72 	},
73 };
74 
75 static struct push_switch_platform_info s3_platform_data = {
76 	.name		= "s3",
77 	.bit		= 5,
78 	.irq_flags	= IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING |
79 			  IRQF_SHARED,
80 	.irq_handler	= psw_irq_handler,
81 };
82 
83 static struct platform_device s3_switch_device = {
84 	.name		= "push-switch",
85 	.id		= 1,
86 	.num_resources	= ARRAY_SIZE(psw_resources),
87 	.resource	= psw_resources,
88 	.dev		= {
89 		.platform_data = &s3_platform_data,
90 	},
91 };
92 
93 static struct push_switch_platform_info s4_platform_data = {
94 	.name		= "s4",
95 	.bit		= 4,
96 	.irq_flags	= IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING |
97 			  IRQF_SHARED,
98 	.irq_handler	= psw_irq_handler,
99 };
100 
101 static struct platform_device s4_switch_device = {
102 	.name		= "push-switch",
103 	.id		= 2,
104 	.num_resources	= ARRAY_SIZE(psw_resources),
105 	.resource	= psw_resources,
106 	.dev		= {
107 		.platform_data = &s4_platform_data,
108 	},
109 };
110 
111 static struct platform_device *psw_devices[] = {
112 	&s2_switch_device, &s3_switch_device, &s4_switch_device,
113 };
114 
115 static int __init psw_init(void)
116 {
117 	return platform_add_devices(psw_devices, ARRAY_SIZE(psw_devices));
118 }
119 module_init(psw_init);
120