/*
* drivers/input/serio/gscps2.c
*
* Copyright (c) 2004-2006 Helge Deller <deller@gmx.de>
* Copyright (c) 2002 Laurent Canet <canetl@esiee.fr>
* Copyright (c) 2002 Thibaut Varene <varenet@parisc-linux.org>
*
* Pieces of code based on linux-2.4's hp_mouse.c & hp_keyb.c
* Copyright (c) 1999 Alex deVries <alex@onefishtwo.ca>
* Copyright (c) 1999-2000 Philipp Rumpf <prumpf@tux.org>
* Copyright (c) 2000 Xavier Debacker <debackex@esiee.fr>
* Copyright (c) 2000-2001 Thomas Marteau <marteaut@esiee.fr>
*
* HP GSC PS/2 port driver, found in PA/RISC Workstations
*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*
* TODO:
* - Dino testing (did HP ever shipped a machine on which this port
* was usable/enabled ?)
*/
#include <linux/init.h>
#include <linux/module.h>
#include <linux/serio.h>
#include <linux/input.h>
#include <linux/interrupt.h>
#include <linux/spinlock.h>
#include <linux/delay.h>
#include <linux/ioport.h>
#include <linux/pci_ids.h>
#include <asm/irq.h>
#include <asm/io.h>
#include <asm/parisc-device.h>
MODULE_AUTHOR("Laurent Canet <canetl@esiee.fr>, Thibaut Varene <varenet@parisc-linux.org>, Helge Deller <deller@gmx.de>");
MODULE_DESCRIPTION("HP GSC PS2 port driver");
MODULE_LICENSE("GPL");
MODULE_DEVICE_TABLE(parisc, gscps2_device_tbl);
#define PFX "gscps2.c: "
/*
* Driver constants
*/
/* various constants */
#define ENABLE 1
#define DISABLE 0
#define GSC_DINO_OFFSET 0x0800 /* offset for DINO controller versus LASI one */
/* PS/2 IO port offsets */
#define GSC_ID 0x00 /* device ID offset (see: GSC_ID_XXX) */
#define GSC_RESET 0x00 /* reset port offset */
#define GSC_RCVDATA 0x04 /* receive port offset */
#define GSC_XMTDATA 0x04 /* transmit port offset */
#define GSC_CONTROL 0x08 /* see: Control register bits */
#define GSC_STATUS 0x0C /* see: Status register bits */
/* Control register bits */
#define GSC_CTRL_ENBL 0x01 /* enable interface */
#define GSC_CTRL_LPBXR 0x02 /* loopback operation */
#define GSC_CTRL_DIAG 0x20 /* directly control clock/data line */
#define GSC_CTRL_DATDIR 0x40 /* data line direct control */
#define GSC_CTRL_CLKDIR 0x80 /* clock line direct control */
/* Status register bits */
#define GSC_STAT_RBNE 0x01 /* Receive Buffer Not Empty */
#define GSC_STAT_TBNE 0x02 /* Transmit Buffer Not Empty */
#define GSC_STAT_TERR 0x04 /* Timeout Error */
#define GSC_STAT_PERR 0x08 /* Parity Error */
#define GSC_STAT_CMPINTR 0x10 /* Composite Interrupt = irq on any port */
#define GSC_STAT_DATSHD 0x40 /* Data Line Shadow */
#define GSC_STAT_CLKSHD 0x80 /* Clock Line Shadow */
/* IDs returned by GSC_ID port register */
#define GSC_ID_KEYBOARD 0 /* device ID values */
#define GSC_ID_MOUSE 1
static irqreturn_t gscps2_interrupt(int irq, void *dev);
#define BUFFER_SIZE 0x0f
/* GSC PS/2 port device struct */
struct gscps2port {
struct list_head node;
struct parisc_device *padev;
struct serio *port;
spinlock_t lock;
char *addr;
u8 act, append; /* position in buffer[] */
struct {
u8 data;
u8 str;
} buffer[BUFFER_SIZE+1];
int id;
};
/*
* Various HW level routines
*/
#define gscps2_readb_input(x) readb((x)+GSC_RCVDATA)
#define gscps2_readb_control(x) readb((x)+GSC_CONTROL)
#define gscps2_readb_status(x) readb((x)+GSC_STATUS)
#define gscps2_writeb_control(x, y) writeb((x), (y)+GSC_CONTROL)
/*
* wait_TBE() - wait for Transmit Buffer Empty
*/
static int wait_TBE(char *addr)
{
int timeout = 25000; /* device is expected to react within 250 msec */
while (gscps2_readb_status(addr) & GSC_STAT_TBNE) {
if (!--timeout)
return 0; /* This should not happen */
udelay(10);
}
return 1;
}
/*
* gscps2_flush() - flush the receive buffer
*/
static void gscps2_flush(struct gscps2port *ps2port)
{
while (gscps2_readb_status(ps2port->addr) & GSC_STAT_RBNE)
gscps2_readb_input(ps2port->addr);
ps2port->act = ps2port->append = 0;
}
/*
* gscps2_writeb_output() - write a byte to the port
*
* returns 1 on success, 0 on error
*/
static inline int gscps2_writeb_output(struct gscps2port *ps2port, u8 data)
{
unsigned long flags;
char *addr = ps2port->addr;
if (!wait_TBE(addr)) {
printk(KERN_DEBUG PFX "timeout - could not write byte %#x\n", data);
return 0;
}
while (gscps2_readb_status(ps2port->addr) & GSC_STAT_RBNE)
/* wait */;
spin_lock_irqsave(&ps2port->lock, flags);
writeb(data, addr+GSC_XMTDATA);
spin_unlock_irqrestore(&ps2port->lock, flags);
/* this is ugly, but due to timing of the port it seems to be necessary. */
mdelay(6);
/* make sure any received data is returned as fast as possible */
/* this is important e.g. when we set the LEDs on the keyboard */
gscps2_interrupt(0, NULL);
return 1;
}
/*
* gscps2_enable() - enables or disables the port
*/
static void gscps2_enable(struct gscps2port *ps2port, int enable)
{
unsigned long flags;
u8 data;
/* now enable/disable the port */
spin_lock_irqsave(&ps2port->lock, flags);
gscps2_flush(ps2port);
data = gscps2_readb_control(ps2port->addr);
if (enable)
data |= GSC_CTRL_ENBL;
else
data &= ~GSC_CTRL_ENBL;
gscps2_writeb_control(data, ps2port->addr);
spin_unlock_irqrestore(&ps2port->lock, flags);
wait_TBE(ps2port->addr);
gscps2_flush(ps2port);
}
/*
* gscps2_reset() - resets the PS/2 port
*/
static void gscps2_reset(struct gscps2port *ps2port)
{
char *addr = ps2port->addr;
unsigned long flags;
/* reset the interface */
spin_lock_irqsave(&ps2port->lock, flags);
gscps2_flush(ps2port);
writeb(0xff, addr+GSC_RESET);
gscps2_flush(ps2port);
spin_unlock_irqrestore(&ps2port->lock, flags);
}
static LIST_HEAD(ps2port_list);
/**
* gscps2_interrupt() - Interruption service routine
*
* This function reads received PS/2 bytes and processes them on
* all interfaces.
* The problematic part here is, that the keyboard and mouse PS/2 port
* share the same interrupt and it's not possible to send data if any
* one of them holds input data. To solve this problem we try to receive
* the data as fast as possible and handle the reporting to the upper layer
* later.
*/
static irqreturn_t gscps2_interrupt(int irq, void *dev)
{
struct gscps2port *ps2port;
list_for_each_entry(ps2port, &ps2port_list, node) {
unsigned long flags;
spin_lock_irqsave(&ps2port->lock, flags);
while ( (ps2port->buffer[ps2port->append].str =
gscps2_readb_status(ps2port->addr)) & GSC_STAT_RBNE ) {
ps2port->buffer[ps2port->append].data =
gscps2_readb_input(ps2port->addr);
ps2port->append = ((ps2port->append+1) & BUFFER_SIZE);
}
spin_unlock_irqrestore(&ps2port->lock, flags);
} /* list_for_each_entry */
/* all data was read from the ports - now report the data to upper layer */
list_for_each_entry(ps2port, &ps2port_list, node) {
while (ps2port->act != ps2port->append) {
unsigned int rxflags;
u8 data, status;
/* Did new data arrived while we read existing data ?
If yes, exit now and let the new irq handler start over again */
if (gscps2_readb_status(ps2port->addr) & GSC_STAT_CMPINTR)
return IRQ_HANDLED;
status = ps2port->buffer[ps2port->act].str;
data = ps2port->buffer[ps2port->act].data;
ps2port->act = ((ps2port->act+1) & BUFFER_SIZE);
rxflags = ((status & GSC_STAT_TERR) ? SERIO_TIMEOUT : 0 ) |
((status & GSC_STAT_PERR) ? SERIO_PARITY : 0 );
serio_interrupt(ps2port->port, data, rxflags);
} /* while() */
} /* list_for_each_entry */
return IRQ_HANDLED;
}
/*
* gscps2_write() - send a byte out through the aux interface.
*/
static int gscps2_write(struct serio *port, unsigned char data)
{
struct gscps2port *ps2port = port->port_data;
if (!gscps2_writeb_output(ps2port, data)) {
printk(KERN_DEBUG PFX "sending byte %#x failed.\n", data);
return -1;
}
return 0;
}
/*
* gscps2_open() is called when a port is opened by the higher layer.
* It resets and enables the port.
*/
static int gscps2_open(struct serio *port)
{
struct gscps2port *ps2port = port->port_data;
gscps2_reset(ps2port);
/* enable it */
gscps2_enable(ps2port, ENABLE);
gscps2_interrupt(0, NULL);
return 0;
}
/*
* gscps2_close() disables the port
*/
static void gscps2_close(struct serio *port)
{
struct gscps2port *ps2port = port->port_data;
gscps2_enable(ps2port, DISABLE);
}
/**
* gscps2_probe() - Probes PS2 devices
* @return: success/error report
*/
static int __init gscps2_probe(struct parisc_device *dev)
{
struct gscps2port *ps2port;
struct serio *serio;
unsigned long hpa = dev->hpa.start;
int ret;
if (!dev->irq)
return -ENODEV;
/* Offset for DINO PS/2. Works with LASI even */
if (dev->id.sversion == 0x96)
hpa += GSC_DINO_OFFSET;
ps2port = kzalloc(sizeof(struct gscps2port), GFP_KERNEL);
serio = kzalloc(sizeof(struct serio), GFP_KERNEL);
if (!ps2port || !serio) {
ret = -ENOMEM;
goto fail_nomem;
}
dev_set_drvdata(&dev->dev, ps2port);
ps2port->port = serio;
ps2port->padev = dev;
ps2port->addr = ioremap_nocache(hpa, GSC_STATUS + 4);
spin_lock_init(&ps2port->lock);
gscps2_reset(ps2port);
ps2port->id = readb(ps2port->addr + GSC_ID) & 0x0f;
snprintf(serio->name, sizeof(serio->name), "GSC PS/2 %s",
(ps2port->id == GSC_ID_KEYBOARD) ? "keyboard" : "mouse");
strlcpy(serio->phys, dev->dev.bus_id, sizeof(serio->phys));
serio->id.type = SERIO_8042;
serio->write = gscps2_write;
serio->open = gscps2_open;
serio->close = gscps2_close;
serio->port_data = ps2port;
serio->dev.parent = &dev->dev;
ret = -EBUSY;
if (request_irq(dev->irq, gscps2_interrupt, IRQF_SHARED, ps2port->port->name, ps2port))
goto fail_miserably;
if (ps2port->id != GSC_ID_KEYBOARD && ps2port->id != GSC_ID_MOUSE) {
printk(KERN_WARNING PFX "Unsupported PS/2 port at 0x%08lx (id=%d) ignored\n",
hpa, ps2port->id);
ret = -ENODEV;
goto fail;
}
#if 0
if (!request_mem_region(hpa, GSC_STATUS + 4, ps2port->port.name))
goto fail;
#endif
printk(KERN_INFO "serio: %s port at 0x%p irq %d @ %s\n",
ps2port->port->name,
ps2port->addr,
ps2port->padev->irq,
ps2port->port->phys);
serio_register_port(ps2port->port);
list_add_tail(&ps2port->node, &ps2port_list);
return 0;
fail:
free_irq(dev->irq, ps2port);
fail_miserably:
iounmap(ps2port->addr);
release_mem_region(dev->hpa.start, GSC_STATUS + 4);
fail_nomem:
kfree(ps2port);
kfree(serio);
return ret;
}
/**
* gscps2_remove() - Removes PS2 devices
* @return: success/error report
*/
static int __devexit gscps2_remove(struct parisc_device *dev)
{
struct gscps2port *ps2port = dev_get_drvdata(&dev->dev);
serio_unregister_port(ps2port->port);
free_irq(dev->irq, ps2port);
gscps2_flush(ps2port);
list_del(&ps2port->node);
iounmap(ps2port->addr);
#if 0
release_mem_region(dev->hpa, GSC_STATUS + 4);
#endif
dev_set_drvdata(&dev->dev, NULL);
kfree(ps2port);
return 0;
}
static struct parisc_device_id gscps2_device_tbl[] = {
{ HPHW_FIO, HVERSION_REV_ANY_ID, HVERSION_ANY_ID, 0x00084 }, /* LASI PS/2 */
#ifdef DINO_TESTED
{ HPHW_FIO, HVERSION_REV_ANY_ID, HVERSION_ANY_ID, 0x00096 }, /* DINO PS/2 */
#endif
{ 0, } /* 0 terminated list */
};
static struct parisc_driver parisc_ps2_driver = {
.name = "gsc_ps2",
.id_table = gscps2_device_tbl,
.probe = gscps2_probe,
.remove = gscps2_remove,
};
static int __init gscps2_init(void)
{
register_parisc_driver(&parisc_ps2_driver);
return 0;
}
static void __exit gscps2_exit(void)
{
unregister_parisc_driver(&parisc_ps2_driver);
}
module_init(gscps2_init);
module_exit(gscps2_exit);
