linux/drivers/net/can/sja1000/sja1000_of_platform.c
Jeff Kirsher 05780d9808 can: Fix FSF address in file headers
Several files refer to an old address for the Free Software Foundation
in the file header comment.  Resolve by replacing the address with
the URL <http://www.gnu.org/licenses/> so that we do not have to keep
updating the header comments anytime the address changes.

CC: Wolfgang Grandegger <wg@grandegger.com>
CC: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2013-12-17 11:47:21 +01:00

221 lines
5.5 KiB
C

/*
* Driver for SJA1000 CAN controllers on the OpenFirmware platform bus
*
* Copyright (C) 2008-2009 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.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, see <http://www.gnu.org/licenses/>.
*/
/* This is a generic driver for SJA1000 chips on the OpenFirmware platform
* bus found on embedded PowerPC systems. You need a SJA1000 CAN node
* definition in your flattened device tree source (DTS) file similar to:
*
* can@3,100 {
* compatible = "nxp,sja1000";
* reg = <3 0x100 0x80>;
* interrupts = <2 0>;
* interrupt-parent = <&mpic>;
* nxp,external-clock-frequency = <16000000>;
* };
*
* See "Documentation/devicetree/bindings/net/can/sja1000.txt" for further
* information.
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/interrupt.h>
#include <linux/netdevice.h>
#include <linux/delay.h>
#include <linux/io.h>
#include <linux/can/dev.h>
#include <linux/of_platform.h>
#include <linux/of_address.h>
#include <linux/of_irq.h>
#include "sja1000.h"
#define DRV_NAME "sja1000_of_platform"
MODULE_AUTHOR("Wolfgang Grandegger <wg@grandegger.com>");
MODULE_DESCRIPTION("Socket-CAN driver for SJA1000 on the OF platform bus");
MODULE_LICENSE("GPL v2");
#define SJA1000_OFP_CAN_CLOCK (16000000 / 2)
#define SJA1000_OFP_OCR OCR_TX0_PULLDOWN
#define SJA1000_OFP_CDR (CDR_CBP | CDR_CLK_OFF)
static u8 sja1000_ofp_read_reg(const struct sja1000_priv *priv, int reg)
{
return ioread8(priv->reg_base + reg);
}
static void sja1000_ofp_write_reg(const struct sja1000_priv *priv,
int reg, u8 val)
{
iowrite8(val, priv->reg_base + reg);
}
static int sja1000_ofp_remove(struct platform_device *ofdev)
{
struct net_device *dev = platform_get_drvdata(ofdev);
struct sja1000_priv *priv = netdev_priv(dev);
struct device_node *np = ofdev->dev.of_node;
struct resource res;
unregister_sja1000dev(dev);
free_sja1000dev(dev);
iounmap(priv->reg_base);
irq_dispose_mapping(dev->irq);
of_address_to_resource(np, 0, &res);
release_mem_region(res.start, resource_size(&res));
return 0;
}
static int sja1000_ofp_probe(struct platform_device *ofdev)
{
struct device_node *np = ofdev->dev.of_node;
struct net_device *dev;
struct sja1000_priv *priv;
struct resource res;
u32 prop;
int err, irq, res_size;
void __iomem *base;
err = of_address_to_resource(np, 0, &res);
if (err) {
dev_err(&ofdev->dev, "invalid address\n");
return err;
}
res_size = resource_size(&res);
if (!request_mem_region(res.start, res_size, DRV_NAME)) {
dev_err(&ofdev->dev, "couldn't request %pR\n", &res);
return -EBUSY;
}
base = ioremap_nocache(res.start, res_size);
if (!base) {
dev_err(&ofdev->dev, "couldn't ioremap %pR\n", &res);
err = -ENOMEM;
goto exit_release_mem;
}
irq = irq_of_parse_and_map(np, 0);
if (irq == 0) {
dev_err(&ofdev->dev, "no irq found\n");
err = -ENODEV;
goto exit_unmap_mem;
}
dev = alloc_sja1000dev(0);
if (!dev) {
err = -ENOMEM;
goto exit_dispose_irq;
}
priv = netdev_priv(dev);
priv->read_reg = sja1000_ofp_read_reg;
priv->write_reg = sja1000_ofp_write_reg;
err = of_property_read_u32(np, "nxp,external-clock-frequency", &prop);
if (!err)
priv->can.clock.freq = prop / 2;
else
priv->can.clock.freq = SJA1000_OFP_CAN_CLOCK; /* default */
err = of_property_read_u32(np, "nxp,tx-output-mode", &prop);
if (!err)
priv->ocr |= prop & OCR_MODE_MASK;
else
priv->ocr |= OCR_MODE_NORMAL; /* default */
err = of_property_read_u32(np, "nxp,tx-output-config", &prop);
if (!err)
priv->ocr |= (prop << OCR_TX_SHIFT) & OCR_TX_MASK;
else
priv->ocr |= OCR_TX0_PULLDOWN; /* default */
err = of_property_read_u32(np, "nxp,clock-out-frequency", &prop);
if (!err && prop) {
u32 divider = priv->can.clock.freq * 2 / prop;
if (divider > 1)
priv->cdr |= divider / 2 - 1;
else
priv->cdr |= CDR_CLKOUT_MASK;
} else {
priv->cdr |= CDR_CLK_OFF; /* default */
}
if (!of_property_read_bool(np, "nxp,no-comparator-bypass"))
priv->cdr |= CDR_CBP; /* default */
priv->irq_flags = IRQF_SHARED;
priv->reg_base = base;
dev->irq = irq;
dev_info(&ofdev->dev,
"reg_base=0x%p irq=%d clock=%d ocr=0x%02x cdr=0x%02x\n",
priv->reg_base, dev->irq, priv->can.clock.freq,
priv->ocr, priv->cdr);
platform_set_drvdata(ofdev, dev);
SET_NETDEV_DEV(dev, &ofdev->dev);
err = register_sja1000dev(dev);
if (err) {
dev_err(&ofdev->dev, "registering %s failed (err=%d)\n",
DRV_NAME, err);
goto exit_free_sja1000;
}
return 0;
exit_free_sja1000:
free_sja1000dev(dev);
exit_dispose_irq:
irq_dispose_mapping(irq);
exit_unmap_mem:
iounmap(base);
exit_release_mem:
release_mem_region(res.start, res_size);
return err;
}
static struct of_device_id sja1000_ofp_table[] = {
{.compatible = "nxp,sja1000"},
{},
};
MODULE_DEVICE_TABLE(of, sja1000_ofp_table);
static struct platform_driver sja1000_ofp_driver = {
.driver = {
.owner = THIS_MODULE,
.name = DRV_NAME,
.of_match_table = sja1000_ofp_table,
},
.probe = sja1000_ofp_probe,
.remove = sja1000_ofp_remove,
};
module_platform_driver(sja1000_ofp_driver);