summaryrefslogtreecommitdiff
path: root/arch/mips/pmc-sierra/msp71xx/msp_hwbutton.c
blob: bb57ed9ea2bd73c01a139500614c70f61d531cd1 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
/*
 * Sets up interrupt handlers for various hardware switches which are
 * connected to interrupt lines.
 *
 * Copyright 2005-2207 PMC-Sierra, Inc.
 *
 *  This program is free software; you can redistribute  it and/or modify it
 *  under  the terms of  the GNU General  Public License as published by the
 *  Free Software Foundation;  either version 2 of the  License, or (at your
 *  option) any later version.
 *
 *  THIS  SOFTWARE  IS PROVIDED   ``AS  IS'' AND   ANY  EXPRESS OR IMPLIED
 *  WARRANTIES,   INCLUDING, BUT NOT  LIMITED  TO, THE IMPLIED WARRANTIES OF
 *  MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN
 *  NO  EVENT  SHALL   THE AUTHOR  BE    LIABLE FOR ANY   DIRECT, INDIRECT,
 *  INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 *  NOT LIMITED   TO, PROCUREMENT OF  SUBSTITUTE GOODS  OR SERVICES; LOSS OF
 *  USE, DATA,  OR PROFITS; OR  BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
 *  ANY THEORY OF LIABILITY, WHETHER IN  CONTRACT, STRICT LIABILITY, OR TORT
 *  (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 *  THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 *  You should have received a copy of the  GNU General Public License along
 *  with this program; if not, write  to the Free Software Foundation, Inc.,
 *  675 Mass Ave, Cambridge, MA 02139, USA.
 */

#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/interrupt.h>

#include <msp_int.h>
#include <msp_regs.h>
#include <msp_regops.h>

/* For hwbutton_interrupt->initial_state */
#define HWBUTTON_HI	0x1
#define HWBUTTON_LO	0x2

/*
 * This struct describes a hardware button
 */
struct hwbutton_interrupt {
	char *name;			/* Name of button */
	int irq;			/* Actual LINUX IRQ */
	int eirq;			/* Extended IRQ number (0-7) */
	int initial_state;		/* The "normal" state of the switch */
	void (*handle_hi)(void *);	/* Handler: switch input has gone HI */
	void (*handle_lo)(void *);	/* Handler: switch input has gone LO */
	void *data;			/* Optional data to pass to handler */
};

#ifdef CONFIG_PMC_MSP7120_GW
extern void msp_restart(char *);

static void softreset_push(void *data)
{
	printk(KERN_WARNING "SOFTRESET switch was pushed\n");

	/*
	 * In the future you could move this to the release handler,
	 * timing the difference between the 'push' and 'release', and only
	 * doing this ungraceful restart if the button has been down for
	 * a certain amount of time; otherwise doing a graceful restart.
	 */

	msp_restart(NULL);
}

static void softreset_release(void *data)
{
	printk(KERN_WARNING "SOFTRESET switch was released\n");

	/* Do nothing */
}

static void standby_on(void *data)
{
	printk(KERN_WARNING "STANDBY switch was set to ON (not implemented)\n");

	/* TODO: Put board in standby mode */
}

static void standby_off(void *data)
{
	printk(KERN_WARNING
		"STANDBY switch was set to OFF (not implemented)\n");

	/* TODO: Take out of standby mode */
}

static struct hwbutton_interrupt softreset_sw = {
	.name = "Softreset button",
	.irq = MSP_INT_EXT0,
	.eirq = 0,
	.initial_state = HWBUTTON_HI,
	.handle_hi = softreset_release,
	.handle_lo = softreset_push,
	.data = NULL,
};

static struct hwbutton_interrupt standby_sw = {
	.name = "Standby switch",
	.irq = MSP_INT_EXT1,
	.eirq = 1,
	.initial_state = HWBUTTON_HI,
	.handle_hi = standby_off,
	.handle_lo = standby_on,
	.data = NULL,
};
#endif /* CONFIG_PMC_MSP7120_GW */

static irqreturn_t hwbutton_handler(int irq, void *data)
{
	struct hwbutton_interrupt *hirq = data;
	unsigned long cic_ext = *CIC_EXT_CFG_REG;

	if (CIC_EXT_IS_ACTIVE_HI(cic_ext, hirq->eirq)) {
		/* Interrupt: pin is now HI */
		CIC_EXT_SET_ACTIVE_LO(cic_ext, hirq->eirq);
		hirq->handle_hi(hirq->data);
	} else {
		/* Interrupt: pin is now LO */
		CIC_EXT_SET_ACTIVE_HI(cic_ext, hirq->eirq);
		hirq->handle_lo(hirq->data);
	}

	/*
	 * Invert the POLARITY of this level interrupt to ack the interrupt
	 * Thus next state change will invoke the opposite message
	 */
	*CIC_EXT_CFG_REG = cic_ext;

	return IRQ_HANDLED;
}

static int msp_hwbutton_register(struct hwbutton_interrupt *hirq)
{
	unsigned long cic_ext;

	if (hirq->handle_hi == NULL || hirq->handle_lo == NULL)
		return -EINVAL;

	cic_ext = *CIC_EXT_CFG_REG;
	CIC_EXT_SET_TRIGGER_LEVEL(cic_ext, hirq->eirq);
	if (hirq->initial_state == HWBUTTON_HI)
		CIC_EXT_SET_ACTIVE_LO(cic_ext, hirq->eirq);
	else
		CIC_EXT_SET_ACTIVE_HI(cic_ext, hirq->eirq);
	*CIC_EXT_CFG_REG = cic_ext;

	return request_irq(hirq->irq, hwbutton_handler, 0,
			   hirq->name, hirq);
}

static int __init msp_hwbutton_setup(void)
{
#ifdef CONFIG_PMC_MSP7120_GW
	msp_hwbutton_register(&softreset_sw);
	msp_hwbutton_register(&standby_sw);
#endif
	return 0;
}

subsys_initcall(msp_hwbutton_setup);