/*
* Driver for CC770 and AN82527 CAN controllers on the legacy ISA bus
*
* Copyright (C) 2009, 2011 Wolfgang Grandegger <wg@grandegger.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the version 2 of the GNU General Public License
* as published by the Free Software Foundation
*
* 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.
*/
/*
* Bosch CC770 and Intel AN82527 CAN controllers on the ISA or PC-104 bus.
* The I/O port or memory address and the IRQ number must be specified via
* module parameters:
*
* insmod cc770_isa.ko port=0x310,0x380 irq=7,11
*
* for ISA devices using I/O ports or:
*
* insmod cc770_isa.ko mem=0xd1000,0xd1000 irq=7,11
*
* for memory mapped ISA devices.
*
* Indirect access via address and data port is supported as well:
*
* insmod cc770_isa.ko port=0x310,0x380 indirect=1 irq=7,11
*
* Furthermore, the following mode parameter can be defined:
*
* clk: External oscillator clock frequency (default=16000000 [16 MHz])
* cir: CPU interface register (default=0x40 [DSC])
* bcr: Bus configuration register (default=0x40 [CBY])
* cor: Clockout register (default=0x00)
*
* Note: for clk, cir, bcr and cor, the first argument re-defines the
* default for all other devices, e.g.:
*
* insmod cc770_isa.ko mem=0xd1000,0xd1000 irq=7,11 clk=24000000
*
* is equivalent to
*
* insmod cc770_isa.ko mem=0xd1000,0xd1000 irq=7,11 clk=24000000,24000000
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/interrupt.h>
#include <linux/netdevice.h>
#include <linux/delay.h>
#include <linux/irq.h>
#include <linux/io.h>
#include <linux/can.h>
#include <linux/can/dev.h>
#include <linux/can/platform/cc770.h>
#include "cc770.h"
#define MAXDEV 8
MODULE_AUTHOR("Wolfgang Grandegger <wg@grandegger.com>");
MODULE_DESCRIPTION("Socket-CAN driver for CC770 on the ISA bus");
MODULE_LICENSE("GPL v2");
#define CLK_DEFAULT 16000000 /* 16 MHz */
#define COR_DEFAULT 0x00
#define BCR_DEFAULT BUSCFG_CBY
static unsigned long port[MAXDEV];
static unsigned long mem[MAXDEV];
static int irq[MAXDEV];
static int clk[MAXDEV];
static u8 cir[MAXDEV] = {[0 ... (MAXDEV - 1)] = 0xff};
static u8 cor[MAXDEV] = {[0 ... (MAXDEV - 1)] = 0xff};
static u8 bcr[MAXDEV] = {[0 ... (MAXDEV - 1)] = 0xff};
static int indirect[MAXDEV] = {[0 ... (MAXDEV - 1)] = -1};
module_param_array(port, ulong, NULL, S_IRUGO);
MODULE_PARM_DESC(port, "I/O port number");
module_param_array(mem, ulong, NULL, S_IRUGO);
MODULE_PARM_DESC(mem, "I/O memory address");
module_param_array(indirect, int, NULL, S_IRUGO);
MODULE_PARM_DESC(indirect, "Indirect access via address and data port");
module_param_array(irq, int, NULL, S_IRUGO);
MODULE_PARM_DESC(irq, "IRQ number");
module_param_array(clk, int, NULL, S_IRUGO);
MODULE_PARM_DESC(clk, "External oscillator clock frequency "
"(default=16000000 [16 MHz])");
module_param_array(cir, byte, NULL, S_IRUGO);
MODULE_PARM_DESC(cir, "CPU interface register (default=0x40 [DSC])");
module_param_array(cor, byte, NULL, S_IRUGO);
MODULE_PARM_DESC(cor, "Clockout register (default=0x00)");
module_param_array(bcr, byte, NULL, S_IRUGO);
MODULE_PARM_DESC(bcr, "Bus configuration register (default=0x40 [CBY])");
#define CC770_IOSIZE 0x20
#define CC770_IOSIZE_INDIRECT 0x02
/* Spinlock for cc770_isa_port_write_reg_indirect
* and cc770_isa_port_read_reg_indirect
*/
static DEFINE_SPINLOCK(cc770_isa_port_lock);
static struct platform_device *cc770_isa_devs[MAXDEV];
static u8 cc770_isa_mem_read_reg(const struct cc770_priv *priv, int reg)
{
return readb(priv->reg_base + reg);
}
static void cc770_isa_mem_write_reg(const struct cc770_priv *priv,
int reg, u8 val)
{
writeb(val, priv->reg_base + reg);
}
static u8 cc770_isa_port_read_reg(const struct cc770_priv *priv, int reg)
{
return inb((unsigned long)priv->reg_base + reg);
}
static void cc770_isa_port_write_reg(const struct cc770_priv *priv,
int reg, u8 val)
{
outb(val, (unsigned long)priv->reg_base + reg);
}
static u8 cc770_isa_port_read_reg_indirect(const struct cc770_priv *priv,
int reg)
{
unsigned long base = (unsigned long)priv->reg_base;
unsigned long flags;
u8 val;
spin_lock_irqsave(&cc770_isa_port_lock, flags);
outb(reg, base);
val = inb(base + 1);
spin_unlock_irqrestore(&cc770_isa_port_lock, flags);
return val;
}
static void cc770_isa_port_write_reg_indirect(const struct cc770_priv *priv,
int reg, u8 val)
{
unsigned long base = (unsigned long)priv->reg_base;
unsigned long flags;
spin_lock_irqsave(&cc770_isa_port_lock, flags);
outb(reg, base);
outb(val, base + 1);
spin_unlock_irqrestore(&cc770_isa_port_lock, flags);
}
static int cc770_isa_probe(struct platform_device *pdev)
{
struct net_device *dev;
struct cc770_priv *priv;
void __iomem *base = NULL;
int iosize = CC770_IOSIZE;
int idx = pdev->id;
int err;
u32 clktmp;
dev_dbg(&pdev->dev, "probing idx=%d: port=%#lx, mem=%#lx, irq=%d\n",
idx, port[idx], mem[idx], irq[idx]);
if (mem[idx]) {
if (!request_mem_region(mem[idx], iosize, KBUILD_MODNAME)) {
err = -EBUSY;
goto exit;
}
base = ioremap_nocache(mem[idx], iosize);
if (!base) {
err = -ENOMEM;
goto exit_release;
}
} else {
if (indirect[idx] > 0 ||
(indirect[idx] == -1 && indirect[0] > 0))
iosize = CC770_IOSIZE_INDIRECT;
if (!request_region(port[idx], iosize, KBUILD_MODNAME)) {
err = -EBUSY;
goto exit;
}
}
dev = alloc_cc770dev(0);
if (!dev) {
err = -ENOMEM;
goto exit_unmap;
}
priv = netdev_priv(dev);
dev->irq = irq[idx];
priv->irq_flags = IRQF_SHARED;
if (mem[idx]) {
priv->reg_base = base;
dev->base_addr = mem[idx];
priv->read_reg = cc770_isa_mem_read_reg;
priv->write_reg = cc770_isa_mem_write_reg;
} else {
priv->reg_base = (void __iomem *)port[idx];
dev->base_addr = port[idx];
if (iosize == CC770_IOSIZE_INDIRECT) {
priv->read_reg = cc770_isa_port_read_reg_indirect;
priv->write_reg = cc770_isa_port_write_reg_indirect;
} else {
priv->read_reg = cc770_isa_port_read_reg;
priv->write_reg = cc770_isa_port_write_reg;
}
}
if (clk[idx])
clktmp = clk[idx];
else if (clk[0])
clktmp = clk[0];
else
clktmp = CLK_DEFAULT;
priv->can.clock.freq = clktmp;
if (cir[idx] != 0xff) {
priv->cpu_interface = cir[idx];
} else if (cir[0] != 0xff) {
priv->cpu_interface = cir[0];
} else {
/* The system clock may not exceed 10 MHz */
if (clktmp > 10000000) {
priv->cpu_interface |= CPUIF_DSC;
clktmp /= 2;
}
/* The memory clock may not exceed 8 MHz */
if (clktmp > 8000000)
priv->cpu_interface |= CPUIF_DMC;
}
if (priv->cpu_interface & CPUIF_DSC)
priv->can.clock.freq /= 2;
if (bcr[idx] != 0xff)
priv->bus_config = bcr[idx];
else if (bcr[0] != 0xff)
priv->bus_config = bcr[0];
else
priv->bus_config = BCR_DEFAULT;
if (cor[idx] != 0xff)
priv->clkout = cor[idx];
else if (cor[0] != 0xff)
priv->clkout = cor[0];
else
priv->clkout = COR_DEFAULT;
platform_set_drvdata(pdev, dev);
SET_NETDEV_DEV(dev, &pdev->dev);
err = register_cc770dev(dev);
if (err) {
dev_err(&pdev->dev,
"couldn't register device (err=%d)\n", err);
goto exit_unmap;
}
dev_info(&pdev->dev, "device registered (reg_base=0x%p, irq=%d)\n",
priv->reg_base, dev->irq);
return 0;
exit_unmap:
if (mem[idx])
iounmap(base);
exit_release:
if (mem[idx])
release_mem_region(mem[idx], iosize);
else
release_region(port[idx], iosize);
exit:
return err;
}
static int cc770_isa_remove(struct platform_device *pdev)
{
struct net_device *dev = platform_get_drvdata(pdev);
struct cc770_priv *priv = netdev_priv(dev);
int idx = pdev->id;
unregister_cc770dev(dev);
if (mem[idx]) {
iounmap(priv->reg_base);
release_mem_region(mem[idx], CC770_IOSIZE);
} else {
if (priv->read_reg == cc770_isa_port_read_reg_indirect)
release_region(port[idx], CC770_IOSIZE_INDIRECT);
else
release_region(port[idx], CC770_IOSIZE);
}
free_cc770dev(dev);
return 0;
}
static struct platform_driver cc770_isa_driver = {
.probe = cc770_isa_probe,
.remove = cc770_isa_remove,
.driver = {
.name = KBUILD_MODNAME,
},
};
static int __init cc770_isa_init(void)
{
int idx, err;
for (idx = 0; idx < ARRAY_SIZE(cc770_isa_devs); idx++) {
if ((port[idx] || mem[idx]) && irq[idx]) {
cc770_isa_devs[idx] =
platform_device_alloc(KBUILD_MODNAME, idx);
if (!cc770_isa_devs[idx]) {
err = -ENOMEM;
goto exit_free_devices;
}
err = platform_device_add(cc770_isa_devs[idx]);
if (err) {
platform_device_put(cc770_isa_devs[idx]);
goto exit_free_devices;
}
pr_debug("platform device %d: port=%#lx, mem=%#lx, "
"irq=%d\n",
idx, port[idx], mem[idx], irq[idx]);
} else if (idx == 0 || port[idx] || mem[idx]) {
pr_err("insufficient parameters supplied\n");
err = -EINVAL;
goto exit_free_devices;
}
}
err = platform_driver_register(&cc770_isa_driver);
if (err)
goto exit_free_devices;
pr_info("driver for max. %d devices registered\n", MAXDEV);
return 0;
exit_free_devices:
while (--idx >= 0) {
if (cc770_isa_devs[idx])
platform_device_unregister(cc770_isa_devs[idx]);
}
return err;
}
module_init(cc770_isa_init);
static void __exit cc770_isa_exit(void)
{
int idx;
platform_driver_unregister(&cc770_isa_driver);
for (idx = 0; idx < ARRAY_SIZE(cc770_isa_devs); idx++) {
if (cc770_isa_devs[idx])
platform_device_unregister(cc770_isa_devs[idx]);
}
}
module_exit(cc770_isa_exit);