2 * linux/drivers/input/serio/sa1111ps2.c
4 * Copyright (C) 2002 Russell King
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License.
10 #include <linux/module.h>
11 #include <linux/init.h>
12 #include <linux/input.h>
13 #include <linux/serio.h>
14 #include <linux/errno.h>
15 #include <linux/interrupt.h>
16 #include <linux/ioport.h>
17 #include <linux/delay.h>
18 #include <linux/device.h>
19 #include <linux/slab.h>
20 #include <linux/spinlock.h>
24 #include <asm/system.h>
26 #include <asm/hardware/sa1111.h>
30 struct sa1111_dev *dev;
40 * Read all bytes waiting in the PS2 port. There should be
41 * at the most one, but we loop for safety. If there was a
42 * framing error, we have to manually clear the status.
44 static irqreturn_t ps2_rxint(int irq, void *dev_id, struct pt_regs *regs)
46 struct ps2if *ps2if = dev_id;
47 unsigned int scancode, flag, status;
48 int handled = IRQ_NONE;
50 status = sa1111_readl(ps2if->base + SA1111_PS2STAT);
51 while (status & PS2STAT_RXF) {
52 if (status & PS2STAT_STP)
53 sa1111_writel(PS2STAT_STP, ps2if->base + SA1111_PS2STAT);
55 flag = (status & PS2STAT_STP ? SERIO_FRAME : 0) |
56 (status & PS2STAT_RXP ? 0 : SERIO_PARITY);
58 scancode = sa1111_readl(ps2if->base + SA1111_PS2DATA) & 0xff;
60 if (hweight8(scancode) & 1)
63 serio_interrupt(&ps2if->io, scancode, flag, regs);
65 status = sa1111_readl(ps2if->base + SA1111_PS2STAT);
67 handled = IRQ_HANDLED;
74 * Completion of ps2 write
76 static irqreturn_t ps2_txint(int irq, void *dev_id, struct pt_regs *regs)
78 struct ps2if *ps2if = dev_id;
81 spin_lock(&ps2if->lock);
82 status = sa1111_readl(ps2if->base + SA1111_PS2STAT);
83 if (ps2if->head == ps2if->tail) {
86 } else if (status & PS2STAT_TXE) {
87 sa1111_writel(ps2if->buf[ps2if->tail], ps2if->base + SA1111_PS2DATA);
88 ps2if->tail = (ps2if->tail + 1) & (sizeof(ps2if->buf) - 1);
90 spin_unlock(&ps2if->lock);
96 * Write a byte to the PS2 port. We have to wait for the
97 * port to indicate that the transmitter is empty.
99 static int ps2_write(struct serio *io, unsigned char val)
101 struct ps2if *ps2if = io->driver;
105 spin_lock_irqsave(&ps2if->lock, flags);
108 * If the TX register is empty, we can go straight out.
110 if (sa1111_readl(ps2if->base + SA1111_PS2STAT) & PS2STAT_TXE) {
111 sa1111_writel(val, ps2if->base + SA1111_PS2DATA);
113 if (ps2if->head == ps2if->tail)
114 enable_irq(ps2if->dev->irq[1]);
115 head = (ps2if->head + 1) & (sizeof(ps2if->buf) - 1);
116 if (head != ps2if->tail) {
117 ps2if->buf[ps2if->head] = val;
122 spin_unlock_irqrestore(&ps2if->lock, flags);
126 static int ps2_open(struct serio *io)
128 struct ps2if *ps2if = io->driver;
131 sa1111_enable_device(ps2if->dev);
133 ret = request_irq(ps2if->dev->irq[0], ps2_rxint, 0,
134 SA1111_DRIVER_NAME(ps2if->dev), ps2if);
136 printk(KERN_ERR "sa1111ps2: could not allocate IRQ%d: %d\n",
137 ps2if->dev->irq[0], ret);
141 ret = request_irq(ps2if->dev->irq[1], ps2_txint, 0,
142 SA1111_DRIVER_NAME(ps2if->dev), ps2if);
144 printk(KERN_ERR "sa1111ps2: could not allocate IRQ%d: %d\n",
145 ps2if->dev->irq[1], ret);
146 free_irq(ps2if->dev->irq[0], ps2if);
152 enable_irq_wake(ps2if->dev->irq[0]);
154 sa1111_writel(PS2CR_ENA, ps2if->base + SA1111_PS2CR);
158 static void ps2_close(struct serio *io)
160 struct ps2if *ps2if = io->driver;
162 sa1111_writel(0, ps2if->base + SA1111_PS2CR);
164 disable_irq_wake(ps2if->dev->irq[0]);
168 free_irq(ps2if->dev->irq[1], ps2if);
169 free_irq(ps2if->dev->irq[0], ps2if);
171 sa1111_disable_device(ps2if->dev);
175 * Clear the input buffer.
177 static void __init ps2_clear_input(struct ps2if *ps2if)
182 if ((sa1111_readl(ps2if->base + SA1111_PS2DATA) & 0xff) == 0xff)
187 static inline unsigned int
188 ps2_test_one(struct ps2if *ps2if, unsigned int mask)
192 sa1111_writel(PS2CR_ENA | mask, ps2if->base + SA1111_PS2CR);
196 val = sa1111_readl(ps2if->base + SA1111_PS2STAT);
197 return val & (PS2STAT_KBC | PS2STAT_KBD);
201 * Test the keyboard interface. We basically check to make sure that
202 * we can drive each line to the keyboard independently of each other.
204 static int __init ps2_test(struct ps2if *ps2if)
209 stat = ps2_test_one(ps2if, PS2CR_FKC);
210 if (stat != PS2STAT_KBD) {
211 printk("PS/2 interface test failed[1]: %02x\n", stat);
215 stat = ps2_test_one(ps2if, 0);
216 if (stat != (PS2STAT_KBC | PS2STAT_KBD)) {
217 printk("PS/2 interface test failed[2]: %02x\n", stat);
221 stat = ps2_test_one(ps2if, PS2CR_FKD);
222 if (stat != PS2STAT_KBC) {
223 printk("PS/2 interface test failed[3]: %02x\n", stat);
227 sa1111_writel(0, ps2if->base + SA1111_PS2CR);
233 * Add one device to this driver.
235 static int ps2_probe(struct sa1111_dev *dev)
240 ps2if = kmalloc(sizeof(struct ps2if), GFP_KERNEL);
245 memset(ps2if, 0, sizeof(struct ps2if));
247 ps2if->io.type = SERIO_8042;
248 ps2if->io.write = ps2_write;
249 ps2if->io.open = ps2_open;
250 ps2if->io.close = ps2_close;
251 ps2if->io.name = dev->dev.bus_id;
252 ps2if->io.phys = dev->dev.bus_id;
253 ps2if->io.driver = ps2if;
255 sa1111_set_drvdata(dev, ps2if);
257 spin_lock_init(&ps2if->lock);
260 * Request the physical region for this PS2 port.
262 if (!request_mem_region(dev->res.start,
263 dev->res.end - dev->res.start + 1,
264 SA1111_DRIVER_NAME(dev))) {
270 * Our parent device has already mapped the region.
272 ps2if->base = (unsigned long)dev->mapbase;
274 sa1111_enable_device(ps2if->dev);
276 /* Incoming clock is 8MHz */
277 sa1111_writel(0, ps2if->base + SA1111_PS2CLKDIV);
278 sa1111_writel(127, ps2if->base + SA1111_PS2PRECNT);
281 * Flush any pending input.
283 ps2_clear_input(ps2if);
286 * Test the keyboard interface.
288 ret = ps2_test(ps2if);
293 * Flush any pending input.
295 ps2_clear_input(ps2if);
297 sa1111_disable_device(ps2if->dev);
298 serio_register_port(&ps2if->io);
302 sa1111_disable_device(ps2if->dev);
303 release_mem_region(dev->res.start,
304 dev->res.end - dev->res.start + 1);
306 sa1111_set_drvdata(dev, NULL);
312 * Remove one device from this driver.
314 static int ps2_remove(struct sa1111_dev *dev)
316 struct ps2if *ps2if = sa1111_get_drvdata(dev);
318 serio_unregister_port(&ps2if->io);
319 release_mem_region(dev->res.start,
320 dev->res.end - dev->res.start + 1);
321 sa1111_set_drvdata(dev, NULL);
329 * Our device driver structure
331 static struct sa1111_driver ps2_driver = {
333 .name = "sa1111-ps2",
335 .devid = SA1111_DEVID_PS2,
337 .remove = ps2_remove,
340 static int __init ps2_init(void)
342 return sa1111_driver_register(&ps2_driver);
345 static void __exit ps2_exit(void)
347 sa1111_driver_unregister(&ps2_driver);
350 module_init(ps2_init);
351 module_exit(ps2_exit);
353 MODULE_AUTHOR("Russell King <rmk@arm.linux.org.uk>");
354 MODULE_DESCRIPTION("SA1111 PS2 controller driver");
355 MODULE_LICENSE("GPL");