1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  *  Copyright (c) 2000-2001 Vojtech Pavlik
4  *  Copyright (c) 2002 Russell King
5  */
6 
7 /*
8  * Acorn RiscPC PS/2 keyboard controller driver for Linux/ARM
9  */
10 
11 #include <linux/module.h>
12 #include <linux/interrupt.h>
13 #include <linux/serio.h>
14 #include <linux/err.h>
15 #include <linux/platform_device.h>
16 #include <linux/io.h>
17 #include <linux/slab.h>
18 
19 #include <mach/hardware.h>
20 #include <asm/hardware/iomd.h>
21 
22 MODULE_AUTHOR("Vojtech Pavlik, Russell King");
23 MODULE_DESCRIPTION("Acorn RiscPC PS/2 keyboard controller driver");
24 MODULE_LICENSE("GPL");
25 MODULE_ALIAS("platform:kart");
26 
27 struct rpckbd_data {
28 	int tx_irq;
29 	int rx_irq;
30 };
31 
rpckbd_write(struct serio * port,unsigned char val)32 static int rpckbd_write(struct serio *port, unsigned char val)
33 {
34 	while (!(iomd_readb(IOMD_KCTRL) & (1 << 7)))
35 		cpu_relax();
36 
37 	iomd_writeb(val, IOMD_KARTTX);
38 
39 	return 0;
40 }
41 
rpckbd_rx(int irq,void * dev_id)42 static irqreturn_t rpckbd_rx(int irq, void *dev_id)
43 {
44 	struct serio *port = dev_id;
45 	unsigned int byte;
46 	int handled = IRQ_NONE;
47 
48 	while (iomd_readb(IOMD_KCTRL) & (1 << 5)) {
49 		byte = iomd_readb(IOMD_KARTRX);
50 
51 		serio_interrupt(port, byte, 0);
52 		handled = IRQ_HANDLED;
53 	}
54 	return handled;
55 }
56 
rpckbd_tx(int irq,void * dev_id)57 static irqreturn_t rpckbd_tx(int irq, void *dev_id)
58 {
59 	return IRQ_HANDLED;
60 }
61 
rpckbd_open(struct serio * port)62 static int rpckbd_open(struct serio *port)
63 {
64 	struct rpckbd_data *rpckbd = port->port_data;
65 
66 	/* Reset the keyboard state machine. */
67 	iomd_writeb(0, IOMD_KCTRL);
68 	iomd_writeb(8, IOMD_KCTRL);
69 	iomd_readb(IOMD_KARTRX);
70 
71 	if (request_irq(rpckbd->rx_irq, rpckbd_rx, 0, "rpckbd", port) != 0) {
72 		printk(KERN_ERR "rpckbd.c: Could not allocate keyboard receive IRQ\n");
73 		return -EBUSY;
74 	}
75 
76 	if (request_irq(rpckbd->tx_irq, rpckbd_tx, 0, "rpckbd", port) != 0) {
77 		printk(KERN_ERR "rpckbd.c: Could not allocate keyboard transmit IRQ\n");
78 		free_irq(rpckbd->rx_irq, port);
79 		return -EBUSY;
80 	}
81 
82 	return 0;
83 }
84 
rpckbd_close(struct serio * port)85 static void rpckbd_close(struct serio *port)
86 {
87 	struct rpckbd_data *rpckbd = port->port_data;
88 
89 	free_irq(rpckbd->rx_irq, port);
90 	free_irq(rpckbd->tx_irq, port);
91 }
92 
93 /*
94  * Allocate and initialize serio structure for subsequent registration
95  * with serio core.
96  */
rpckbd_probe(struct platform_device * dev)97 static int rpckbd_probe(struct platform_device *dev)
98 {
99 	struct rpckbd_data *rpckbd;
100 	struct serio *serio;
101 	int tx_irq, rx_irq;
102 
103 	rx_irq = platform_get_irq(dev, 0);
104 	if (rx_irq <= 0)
105 		return rx_irq < 0 ? rx_irq : -ENXIO;
106 
107 	tx_irq = platform_get_irq(dev, 1);
108 	if (tx_irq <= 0)
109 		return tx_irq < 0 ? tx_irq : -ENXIO;
110 
111 	serio = kzalloc(sizeof(struct serio), GFP_KERNEL);
112 	rpckbd = kzalloc(sizeof(*rpckbd), GFP_KERNEL);
113 	if (!serio || !rpckbd) {
114 		kfree(rpckbd);
115 		kfree(serio);
116 		return -ENOMEM;
117 	}
118 
119 	rpckbd->rx_irq = rx_irq;
120 	rpckbd->tx_irq = tx_irq;
121 
122 	serio->id.type		= SERIO_8042;
123 	serio->write		= rpckbd_write;
124 	serio->open		= rpckbd_open;
125 	serio->close		= rpckbd_close;
126 	serio->dev.parent	= &dev->dev;
127 	serio->port_data	= rpckbd;
128 	strscpy(serio->name, "RiscPC PS/2 kbd port", sizeof(serio->name));
129 	strscpy(serio->phys, "rpckbd/serio0", sizeof(serio->phys));
130 
131 	platform_set_drvdata(dev, serio);
132 	serio_register_port(serio);
133 	return 0;
134 }
135 
rpckbd_remove(struct platform_device * dev)136 static int rpckbd_remove(struct platform_device *dev)
137 {
138 	struct serio *serio = platform_get_drvdata(dev);
139 	struct rpckbd_data *rpckbd = serio->port_data;
140 
141 	serio_unregister_port(serio);
142 	kfree(rpckbd);
143 
144 	return 0;
145 }
146 
147 static struct platform_driver rpckbd_driver = {
148 	.probe		= rpckbd_probe,
149 	.remove		= rpckbd_remove,
150 	.driver		= {
151 		.name	= "kart",
152 	},
153 };
154 module_platform_driver(rpckbd_driver);
155