tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1/*
2 * linux/drivers/input/serio/ambakmi.c
3 *
4 * Copyright (C) 2000-2003 Deep Blue Solutions Ltd.
5 * Copyright (C) 2002 Russell King.
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#include <linux/module.h>
13#include <linux/serio.h>
14#include <linux/errno.h>
15#include <linux/interrupt.h>
16#include <linux/ioport.h>
17#include <linux/device.h>
18#include <linux/delay.h>
19#include <linux/slab.h>
20#include <linux/err.h>
21#include <linux/amba/bus.h>
22#include <linux/amba/kmi.h>
23#include <linux/clk.h>
24
25#include <asm/io.h>
26#include <asm/irq.h>
27
28#define KMI_BASE (kmi->base)
29
30struct amba_kmi_port {
31 struct serio *io;
32 struct clk *clk;
33 void __iomem *base;
34 unsigned int irq;
35 unsigned int divisor;
36 unsigned int open;
37};
38
39static irqreturn_t amba_kmi_int(int irq, void *dev_id)
40{
41 struct amba_kmi_port *kmi = dev_id;
42 unsigned int status = readb(KMIIR);
43 int handled = IRQ_NONE;
44
45 while (status & KMIIR_RXINTR) {
46 serio_interrupt(kmi->io, readb(KMIDATA), 0);
47 status = readb(KMIIR);
48 handled = IRQ_HANDLED;
49 }
50
51 return handled;
52}
53
54static int amba_kmi_write(struct serio *io, unsigned char val)
55{
56 struct amba_kmi_port *kmi = io->port_data;
57 unsigned int timeleft = 10000; /* timeout in 100ms */
58
59 while ((readb(KMISTAT) & KMISTAT_TXEMPTY) == 0 && --timeleft)
60 udelay(10);
61
62 if (timeleft)
63 writeb(val, KMIDATA);
64
65 return timeleft ? 0 : SERIO_TIMEOUT;
66}
67
68static int amba_kmi_open(struct serio *io)
69{
70 struct amba_kmi_port *kmi = io->port_data;
71 unsigned int divisor;
72 int ret;
73
74 ret = clk_prepare_enable(kmi->clk);
75 if (ret)
76 goto out;
77
78 divisor = clk_get_rate(kmi->clk) / 8000000 - 1;
79 writeb(divisor, KMICLKDIV);
80 writeb(KMICR_EN, KMICR);
81
82 ret = request_irq(kmi->irq, amba_kmi_int, 0, "kmi-pl050", kmi);
83 if (ret) {
84 printk(KERN_ERR "kmi: failed to claim IRQ%d\n", kmi->irq);
85 writeb(0, KMICR);
86 goto clk_disable;
87 }
88
89 writeb(KMICR_EN | KMICR_RXINTREN, KMICR);
90
91 return 0;
92
93 clk_disable:
94 clk_disable_unprepare(kmi->clk);
95 out:
96 return ret;
97}
98
99static void amba_kmi_close(struct serio *io)
100{
101 struct amba_kmi_port *kmi = io->port_data;
102
103 writeb(0, KMICR);
104
105 free_irq(kmi->irq, kmi);
106 clk_disable_unprepare(kmi->clk);
107}
108
109static int amba_kmi_probe(struct amba_device *dev,
110 const struct amba_id *id)
111{
112 struct amba_kmi_port *kmi;
113 struct serio *io;
114 int ret;
115
116 ret = amba_request_regions(dev, NULL);
117 if (ret)
118 return ret;
119
120 kmi = kzalloc(sizeof(struct amba_kmi_port), GFP_KERNEL);
121 io = kzalloc(sizeof(struct serio), GFP_KERNEL);
122 if (!kmi || !io) {
123 ret = -ENOMEM;
124 goto out;
125 }
126
127
128 io->id.type = SERIO_8042;
129 io->write = amba_kmi_write;
130 io->open = amba_kmi_open;
131 io->close = amba_kmi_close;
132 strlcpy(io->name, dev_name(&dev->dev), sizeof(io->name));
133 strlcpy(io->phys, dev_name(&dev->dev), sizeof(io->phys));
134 io->port_data = kmi;
135 io->dev.parent = &dev->dev;
136
137 kmi->io = io;
138 kmi->base = ioremap(dev->res.start, resource_size(&dev->res));
139 if (!kmi->base) {
140 ret = -ENOMEM;
141 goto out;
142 }
143
144 kmi->clk = clk_get(&dev->dev, "KMIREFCLK");
145 if (IS_ERR(kmi->clk)) {
146 ret = PTR_ERR(kmi->clk);
147 goto unmap;
148 }
149
150 kmi->irq = dev->irq[0];
151 amba_set_drvdata(dev, kmi);
152
153 serio_register_port(kmi->io);
154 return 0;
155
156 unmap:
157 iounmap(kmi->base);
158 out:
159 kfree(kmi);
160 kfree(io);
161 amba_release_regions(dev);
162 return ret;
163}
164
165static int amba_kmi_remove(struct amba_device *dev)
166{
167 struct amba_kmi_port *kmi = amba_get_drvdata(dev);
168
169 serio_unregister_port(kmi->io);
170 clk_put(kmi->clk);
171 iounmap(kmi->base);
172 kfree(kmi);
173 amba_release_regions(dev);
174 return 0;
175}
176
177static int amba_kmi_resume(struct amba_device *dev)
178{
179 struct amba_kmi_port *kmi = amba_get_drvdata(dev);
180
181 /* kick the serio layer to rescan this port */
182 serio_reconnect(kmi->io);
183
184 return 0;
185}
186
187static struct amba_id amba_kmi_idtable[] = {
188 {
189 .id = 0x00041050,
190 .mask = 0x000fffff,
191 },
192 { 0, 0 }
193};
194
195MODULE_DEVICE_TABLE(amba, amba_kmi_idtable);
196
197static struct amba_driver ambakmi_driver = {
198 .drv = {
199 .name = "kmi-pl050",
200 .owner = THIS_MODULE,
201 },
202 .id_table = amba_kmi_idtable,
203 .probe = amba_kmi_probe,
204 .remove = amba_kmi_remove,
205 .resume = amba_kmi_resume,
206};
207
208module_amba_driver(ambakmi_driver);
209
210MODULE_AUTHOR("Russell King <rmk@arm.linux.org.uk>");
211MODULE_DESCRIPTION("AMBA KMI controller driver");
212MODULE_LICENSE("GPL");