348 lines
8.8 KiB
C
348 lines
8.8 KiB
C
/* ------------------------------------------------------------------------- */
|
|
/* i2c-elektor.c i2c-hw access for PCF8584 style isa bus adaptes */
|
|
/* ------------------------------------------------------------------------- */
|
|
/* Copyright (C) 1995-97 Simon G. Vogl
|
|
1998-99 Hans Berglund
|
|
|
|
This program is free software; you can redistribute it and/or modify
|
|
it under the terms of the GNU General Public License as published by
|
|
the Free Software Foundation; either version 2 of the License, or
|
|
(at your option) any later version.
|
|
|
|
This program is distributed in the hope that it will be useful,
|
|
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
GNU General Public License for more details.
|
|
|
|
You should have received a copy of the GNU General Public License
|
|
along with this program; if not, write to the Free Software
|
|
Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */
|
|
/* ------------------------------------------------------------------------- */
|
|
|
|
/* With some changes from Kyösti Mälkki <kmalkki@cc.hut.fi> and even
|
|
Frodo Looijaard <frodol@dds.nl> */
|
|
|
|
/* Partially rewriten by Oleg I. Vdovikin for mmapped support of
|
|
for Alpha Processor Inc. UP-2000(+) boards */
|
|
|
|
#include <linux/kernel.h>
|
|
#include <linux/ioport.h>
|
|
#include <linux/module.h>
|
|
#include <linux/delay.h>
|
|
#include <linux/init.h>
|
|
#include <linux/interrupt.h>
|
|
#include <linux/pci.h>
|
|
#include <linux/wait.h>
|
|
|
|
#include <linux/isa.h>
|
|
#include <linux/i2c.h>
|
|
#include <linux/i2c-algo-pcf.h>
|
|
#include <linux/io.h>
|
|
|
|
#include <asm/irq.h>
|
|
|
|
#include "../algos/i2c-algo-pcf.h"
|
|
|
|
#define DEFAULT_BASE 0x330
|
|
|
|
static int base;
|
|
static u8 __iomem *base_iomem;
|
|
|
|
static int irq;
|
|
static int clock = 0x1c;
|
|
static int own = 0x55;
|
|
static int mmapped;
|
|
|
|
/* vdovikin: removed static struct i2c_pcf_isa gpi; code -
|
|
this module in real supports only one device, due to missing arguments
|
|
in some functions, called from the algo-pcf module. Sometimes it's
|
|
need to be rewriten - but for now just remove this for simpler reading */
|
|
|
|
static wait_queue_head_t pcf_wait;
|
|
static int pcf_pending;
|
|
static spinlock_t lock;
|
|
|
|
static struct i2c_adapter pcf_isa_ops;
|
|
|
|
/* ----- local functions ---------------------------------------------- */
|
|
|
|
static void pcf_isa_setbyte(void *data, int ctl, int val)
|
|
{
|
|
u8 __iomem *address = ctl ? (base_iomem + 1) : base_iomem;
|
|
|
|
/* enable irq if any specified for serial operation */
|
|
if (ctl && irq && (val & I2C_PCF_ESO)) {
|
|
val |= I2C_PCF_ENI;
|
|
}
|
|
|
|
pr_debug("%s: Write %p 0x%02X\n", pcf_isa_ops.name, address, val);
|
|
iowrite8(val, address);
|
|
#ifdef __alpha__
|
|
/* API UP2000 needs some hardware fudging to make the write stick */
|
|
iowrite8(val, address);
|
|
#endif
|
|
}
|
|
|
|
static int pcf_isa_getbyte(void *data, int ctl)
|
|
{
|
|
u8 __iomem *address = ctl ? (base_iomem + 1) : base_iomem;
|
|
int val = ioread8(address);
|
|
|
|
pr_debug("%s: Read %p 0x%02X\n", pcf_isa_ops.name, address, val);
|
|
return (val);
|
|
}
|
|
|
|
static int pcf_isa_getown(void *data)
|
|
{
|
|
return (own);
|
|
}
|
|
|
|
|
|
static int pcf_isa_getclock(void *data)
|
|
{
|
|
return (clock);
|
|
}
|
|
|
|
static void pcf_isa_waitforpin(void *data)
|
|
{
|
|
DEFINE_WAIT(wait);
|
|
int timeout = 2;
|
|
unsigned long flags;
|
|
|
|
if (irq > 0) {
|
|
spin_lock_irqsave(&lock, flags);
|
|
if (pcf_pending == 0) {
|
|
spin_unlock_irqrestore(&lock, flags);
|
|
prepare_to_wait(&pcf_wait, &wait, TASK_INTERRUPTIBLE);
|
|
if (schedule_timeout(timeout*HZ)) {
|
|
spin_lock_irqsave(&lock, flags);
|
|
if (pcf_pending == 1) {
|
|
pcf_pending = 0;
|
|
}
|
|
spin_unlock_irqrestore(&lock, flags);
|
|
}
|
|
finish_wait(&pcf_wait, &wait);
|
|
} else {
|
|
pcf_pending = 0;
|
|
spin_unlock_irqrestore(&lock, flags);
|
|
}
|
|
} else {
|
|
udelay(100);
|
|
}
|
|
}
|
|
|
|
|
|
static irqreturn_t pcf_isa_handler(int this_irq, void *dev_id) {
|
|
spin_lock(&lock);
|
|
pcf_pending = 1;
|
|
spin_unlock(&lock);
|
|
wake_up_interruptible(&pcf_wait);
|
|
return IRQ_HANDLED;
|
|
}
|
|
|
|
|
|
static int pcf_isa_init(void)
|
|
{
|
|
spin_lock_init(&lock);
|
|
if (!mmapped) {
|
|
if (!request_region(base, 2, pcf_isa_ops.name)) {
|
|
printk(KERN_ERR "%s: requested I/O region (%#x:2) is "
|
|
"in use\n", pcf_isa_ops.name, base);
|
|
return -ENODEV;
|
|
}
|
|
base_iomem = ioport_map(base, 2);
|
|
if (!base_iomem) {
|
|
printk(KERN_ERR "%s: remap of I/O region %#x failed\n",
|
|
pcf_isa_ops.name, base);
|
|
release_region(base, 2);
|
|
return -ENODEV;
|
|
}
|
|
} else {
|
|
if (!request_mem_region(base, 2, pcf_isa_ops.name)) {
|
|
printk(KERN_ERR "%s: requested memory region (%#x:2) "
|
|
"is in use\n", pcf_isa_ops.name, base);
|
|
return -ENODEV;
|
|
}
|
|
base_iomem = ioremap(base, 2);
|
|
if (base_iomem == NULL) {
|
|
printk(KERN_ERR "%s: remap of memory region %#x "
|
|
"failed\n", pcf_isa_ops.name, base);
|
|
release_mem_region(base, 2);
|
|
return -ENODEV;
|
|
}
|
|
}
|
|
pr_debug("%s: registers %#x remapped to %p\n", pcf_isa_ops.name, base,
|
|
base_iomem);
|
|
|
|
if (irq > 0) {
|
|
if (request_irq(irq, pcf_isa_handler, 0, pcf_isa_ops.name,
|
|
NULL) < 0) {
|
|
printk(KERN_ERR "%s: Request irq%d failed\n",
|
|
pcf_isa_ops.name, irq);
|
|
irq = 0;
|
|
} else
|
|
enable_irq(irq);
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
/* ------------------------------------------------------------------------
|
|
* Encapsulate the above functions in the correct operations structure.
|
|
* This is only done when more than one hardware adapter is supported.
|
|
*/
|
|
static struct i2c_algo_pcf_data pcf_isa_data = {
|
|
.setpcf = pcf_isa_setbyte,
|
|
.getpcf = pcf_isa_getbyte,
|
|
.getown = pcf_isa_getown,
|
|
.getclock = pcf_isa_getclock,
|
|
.waitforpin = pcf_isa_waitforpin,
|
|
};
|
|
|
|
static struct i2c_adapter pcf_isa_ops = {
|
|
.owner = THIS_MODULE,
|
|
.class = I2C_CLASS_HWMON | I2C_CLASS_SPD,
|
|
.algo_data = &pcf_isa_data,
|
|
.name = "i2c-elektor",
|
|
};
|
|
|
|
static int __devinit elektor_match(struct device *dev, unsigned int id)
|
|
{
|
|
#ifdef __alpha__
|
|
/* check to see we have memory mapped PCF8584 connected to the
|
|
Cypress cy82c693 PCI-ISA bridge as on UP2000 board */
|
|
if (base == 0) {
|
|
struct pci_dev *cy693_dev;
|
|
|
|
cy693_dev = pci_get_device(PCI_VENDOR_ID_CONTAQ,
|
|
PCI_DEVICE_ID_CONTAQ_82C693, NULL);
|
|
if (cy693_dev) {
|
|
unsigned char config;
|
|
/* yeap, we've found cypress, let's check config */
|
|
if (!pci_read_config_byte(cy693_dev, 0x47, &config)) {
|
|
|
|
dev_dbg(dev, "found cy82c693, config "
|
|
"register 0x47 = 0x%02x\n", config);
|
|
|
|
/* UP2000 board has this register set to 0xe1,
|
|
but the most significant bit as seems can be
|
|
reset during the proper initialisation
|
|
sequence if guys from API decides to do that
|
|
(so, we can even enable Tsunami Pchip
|
|
window for the upper 1 Gb) */
|
|
|
|
/* so just check for ROMCS at 0xe0000,
|
|
ROMCS enabled for writes
|
|
and external XD Bus buffer in use. */
|
|
if ((config & 0x7f) == 0x61) {
|
|
/* seems to be UP2000 like board */
|
|
base = 0xe0000;
|
|
mmapped = 1;
|
|
/* UP2000 drives ISA with
|
|
8.25 MHz (PCI/4) clock
|
|
(this can be read from cypress) */
|
|
clock = I2C_PCF_CLK | I2C_PCF_TRNS90;
|
|
dev_info(dev, "found API UP2000 like "
|
|
"board, will probe PCF8584 "
|
|
"later\n");
|
|
}
|
|
}
|
|
pci_dev_put(cy693_dev);
|
|
}
|
|
}
|
|
#endif
|
|
|
|
/* sanity checks for mmapped I/O */
|
|
if (mmapped && base < 0xc8000) {
|
|
dev_err(dev, "incorrect base address (%#x) specified "
|
|
"for mmapped I/O\n", base);
|
|
return 0;
|
|
}
|
|
|
|
if (base == 0) {
|
|
base = DEFAULT_BASE;
|
|
}
|
|
return 1;
|
|
}
|
|
|
|
static int __devinit elektor_probe(struct device *dev, unsigned int id)
|
|
{
|
|
init_waitqueue_head(&pcf_wait);
|
|
if (pcf_isa_init())
|
|
return -ENODEV;
|
|
pcf_isa_ops.dev.parent = dev;
|
|
if (i2c_pcf_add_bus(&pcf_isa_ops) < 0)
|
|
goto fail;
|
|
|
|
dev_info(dev, "found device at %#x\n", base);
|
|
|
|
return 0;
|
|
|
|
fail:
|
|
if (irq > 0) {
|
|
disable_irq(irq);
|
|
free_irq(irq, NULL);
|
|
}
|
|
|
|
if (!mmapped) {
|
|
ioport_unmap(base_iomem);
|
|
release_region(base, 2);
|
|
} else {
|
|
iounmap(base_iomem);
|
|
release_mem_region(base, 2);
|
|
}
|
|
return -ENODEV;
|
|
}
|
|
|
|
static int __devexit elektor_remove(struct device *dev, unsigned int id)
|
|
{
|
|
i2c_del_adapter(&pcf_isa_ops);
|
|
|
|
if (irq > 0) {
|
|
disable_irq(irq);
|
|
free_irq(irq, NULL);
|
|
}
|
|
|
|
if (!mmapped) {
|
|
ioport_unmap(base_iomem);
|
|
release_region(base, 2);
|
|
} else {
|
|
iounmap(base_iomem);
|
|
release_mem_region(base, 2);
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static struct isa_driver i2c_elektor_driver = {
|
|
.match = elektor_match,
|
|
.probe = elektor_probe,
|
|
.remove = __devexit_p(elektor_remove),
|
|
.driver = {
|
|
.owner = THIS_MODULE,
|
|
.name = "i2c-elektor",
|
|
},
|
|
};
|
|
|
|
static int __init i2c_pcfisa_init(void)
|
|
{
|
|
return isa_register_driver(&i2c_elektor_driver, 1);
|
|
}
|
|
|
|
static void __exit i2c_pcfisa_exit(void)
|
|
{
|
|
isa_unregister_driver(&i2c_elektor_driver);
|
|
}
|
|
|
|
MODULE_AUTHOR("Hans Berglund <hb@spacetec.no>");
|
|
MODULE_DESCRIPTION("I2C-Bus adapter routines for PCF8584 ISA bus adapter");
|
|
MODULE_LICENSE("GPL");
|
|
|
|
module_param(base, int, 0);
|
|
module_param(irq, int, 0);
|
|
module_param(clock, int, 0);
|
|
module_param(own, int, 0);
|
|
module_param(mmapped, int, 0);
|
|
|
|
module_init(i2c_pcfisa_init);
|
|
module_exit(i2c_pcfisa_exit);
|