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