summaryrefslogtreecommitdiffstats
path: root/drivers/input/serio/arc_ps2.c
blob: c52e3e589f7283bef15c502c9e14fb3625ad2d43 (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
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
/*
 * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 * Driver is originally developed by Pavel Sokolov <psokolov@synopsys.com>
 */

#include <linux/err.h>
#include <linux/module.h>
#include <linux/interrupt.h>
#include <linux/input.h>
#include <linux/serio.h>
#include <linux/platform_device.h>
#include <linux/io.h>
#include <linux/kernel.h>
#include <linux/slab.h>

#define ARC_PS2_PORTS                   2

#define ARC_ARC_PS2_ID                  0x0001f609

#define STAT_TIMEOUT                    128

#define PS2_STAT_RX_FRM_ERR             (1)
#define PS2_STAT_RX_BUF_OVER            (1 << 1)
#define PS2_STAT_RX_INT_EN              (1 << 2)
#define PS2_STAT_RX_VAL                 (1 << 3)
#define PS2_STAT_TX_ISNOT_FUL           (1 << 4)
#define PS2_STAT_TX_INT_EN              (1 << 5)

struct arc_ps2_port {
	void __iomem *data_addr;
	void __iomem *status_addr;
	struct serio *io;
};

struct arc_ps2_data {
	struct arc_ps2_port port[ARC_PS2_PORTS];
	void __iomem *addr;
	unsigned int frame_error;
	unsigned int buf_overflow;
	unsigned int total_int;
};

static void arc_ps2_check_rx(struct arc_ps2_data *arc_ps2,
			     struct arc_ps2_port *port)
{
	unsigned int timeout = 1000;
	unsigned int flag, status;
	unsigned char data;

	do {
		status = ioread32(port->status_addr);
		if (!(status & PS2_STAT_RX_VAL))
			return;

		data = ioread32(port->data_addr) & 0xff;

		flag = 0;
		arc_ps2->total_int++;
		if (status & PS2_STAT_RX_FRM_ERR) {
			arc_ps2->frame_error++;
			flag |= SERIO_PARITY;
		} else if (status & PS2_STAT_RX_BUF_OVER) {
			arc_ps2->buf_overflow++;
			flag |= SERIO_FRAME;
		}

		serio_interrupt(port->io, data, flag);
	} while (--timeout);

	dev_err(&port->io->dev, "PS/2 hardware stuck\n");
}

static irqreturn_t arc_ps2_interrupt(int irq, void *dev)
{
	struct arc_ps2_data *arc_ps2 = dev;
	int i;

	for (i = 0; i < ARC_PS2_PORTS; i++)
		arc_ps2_check_rx(arc_ps2, &arc_ps2->port[i]);

	return IRQ_HANDLED;
}

static int arc_ps2_write(struct serio *io, unsigned char val)
{
	unsigned status;
	struct arc_ps2_port *port = io->port_data;
	int timeout = STAT_TIMEOUT;

	do {
		status = ioread32(port->status_addr);
		cpu_relax();

		if (status & PS2_STAT_TX_ISNOT_FUL) {
			iowrite32(val & 0xff, port->data_addr);
			return 0;
		}

	} while (--timeout);

	dev_err(&io->dev, "write timeout\n");
	return -ETIMEDOUT;
}

static int arc_ps2_open(struct serio *io)
{
	struct arc_ps2_port *port = io->port_data;

	iowrite32(PS2_STAT_RX_INT_EN, port->status_addr);

	return 0;
}

static void arc_ps2_close(struct serio *io)
{
	struct arc_ps2_port *port = io->port_data;

	iowrite32(ioread32(port->status_addr) & ~PS2_STAT_RX_INT_EN,
		  port->status_addr);
}

static void __iomem *arc_ps2_calc_addr(struct arc_ps2_data *arc_ps2,
						  int index, bool status)
{
	void __iomem *addr;

	addr = arc_ps2->addr + 4 + 4 * index;
	if (status)
		addr += ARC_PS2_PORTS * 4;

	return addr;
}

static void arc_ps2_inhibit_ports(struct arc_ps2_data *arc_ps2)
{
	void __iomem *addr;
	u32 val;
	int i;

	for (i = 0; i < ARC_PS2_PORTS; i++) {
		addr = arc_ps2_calc_addr(arc_ps2, i, true);
		val = ioread32(addr);
		val &= ~(PS2_STAT_RX_INT_EN | PS2_STAT_TX_INT_EN);
		iowrite32(val, addr);
	}
}

static int arc_ps2_create_port(struct platform_device *pdev,
					 struct arc_ps2_data *arc_ps2,
					 int index)
{
	struct arc_ps2_port *port = &arc_ps2->port[index];
	struct serio *io;

	io = kzalloc(sizeof(struct serio), GFP_KERNEL);
	if (!io)
		return -ENOMEM;

	io->id.type = SERIO_8042;
	io->write = arc_ps2_write;
	io->open = arc_ps2_open;
	io->close = arc_ps2_close;
	snprintf(io->name, sizeof(io->name), "ARC PS/2 port%d", index);
	snprintf(io->phys, sizeof(io->phys), "arc/serio%d", index);
	io->port_data = port;

	port->io = io;

	port->data_addr = arc_ps2_calc_addr(arc_ps2, index, false);
	port->status_addr = arc_ps2_calc_addr(arc_ps2, index, true);

	dev_dbg(&pdev->dev, "port%d is allocated (data = 0x%p, status = 0x%p)\n",
		index, port->data_addr, port->status_addr);

	serio_register_port(port->io);
	return 0;
}

static int arc_ps2_probe(struct platform_device *pdev)
{
	struct arc_ps2_data *arc_ps2;
	struct resource *res;
	int irq;
	int error, id, i;

	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	if (!res) {
		dev_err(&pdev->dev, "no IO memory defined\n");
		return -EINVAL;
	}

	irq = platform_get_irq_byname(pdev, "arc_ps2_irq");
	if (irq < 0) {
		dev_err(&pdev->dev, "no IRQ defined\n");
		return -EINVAL;
	}

	arc_ps2 = devm_kzalloc(&pdev->dev, sizeof(struct arc_ps2_data),
				GFP_KERNEL);
	if (!arc_ps2) {
		dev_err(&pdev->dev, "out of memory\n");
		return -ENOMEM;
	}

	arc_ps2->addr = devm_ioremap_resource(&pdev->dev, res);
	if (IS_ERR(arc_ps2->addr))
		return PTR_ERR(arc_ps2->addr);

	dev_info(&pdev->dev, "irq = %d, address = 0x%p, ports = %i\n",
		 irq, arc_ps2->addr, ARC_PS2_PORTS);

	id = ioread32(arc_ps2->addr);
	if (id != ARC_ARC_PS2_ID) {
		dev_err(&pdev->dev, "device id does not match\n");
		return -ENXIO;
	}

	arc_ps2_inhibit_ports(arc_ps2);

	error = devm_request_irq(&pdev->dev, irq, arc_ps2_interrupt,
				 0, "arc_ps2", arc_ps2);
	if (error) {
		dev_err(&pdev->dev, "Could not allocate IRQ\n");
		return error;
	}

	for (i = 0; i < ARC_PS2_PORTS; i++) {
		error = arc_ps2_create_port(pdev, arc_ps2, i);
		if (error) {
			while (--i >= 0)
				serio_unregister_port(arc_ps2->port[i].io);
			return error;
		}
	}

	platform_set_drvdata(pdev, arc_ps2);

	return 0;
}

static int arc_ps2_remove(struct platform_device *pdev)
{
	struct arc_ps2_data *arc_ps2 = platform_get_drvdata(pdev);
	int i;

	for (i = 0; i < ARC_PS2_PORTS; i++)
		serio_unregister_port(arc_ps2->port[i].io);

	dev_dbg(&pdev->dev, "interrupt count = %i\n", arc_ps2->total_int);
	dev_dbg(&pdev->dev, "frame error count = %i\n", arc_ps2->frame_error);
	dev_dbg(&pdev->dev, "buffer overflow count = %i\n",
		arc_ps2->buf_overflow);

	return 0;
}

static struct platform_driver arc_ps2_driver = {
	.driver	= {
		.name	= "arc_ps2",
		.owner	= THIS_MODULE,
	},
	.probe	= arc_ps2_probe,
	.remove	= arc_ps2_remove,
};

module_platform_driver(arc_ps2_driver);

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Pavel Sokolov <psokolov@synopsys.com>");
MODULE_DESCRIPTION("ARC PS/2 Driver");
OpenPOWER on IntegriCloud