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/*
* Copyright (C) 2005 Sascha Hauer, Pengutronix
* Copyright (C) 2007 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/>.
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/interrupt.h>
#include <linux/netdevice.h>
#include <linux/delay.h>
#include <linux/pci.h>
#include <linux/platform_device.h>
#include <linux/irq.h>
#include <linux/can/dev.h>
#include <linux/can/platform/sja1000.h>
#include <linux/io.h>
#include <linux/of.h>
#include <linux/of_irq.h>
#include "sja1000.h"
#define DRV_NAME "sja1000_platform"
#define SP_CAN_CLOCK (16000000 / 2)
MODULE_AUTHOR("Sascha Hauer <s.hauer@pengutronix.de>");
MODULE_AUTHOR("Wolfgang Grandegger <wg@grandegger.com>");
MODULE_DESCRIPTION("Socket-CAN driver for SJA1000 on the platform bus");
MODULE_ALIAS("platform:" DRV_NAME);
MODULE_LICENSE("GPL v2");
static u8 sp_read_reg8(const struct sja1000_priv *priv, int reg)
{
return ioread8(priv->reg_base + reg);
}
static void sp_write_reg8(const struct sja1000_priv *priv, int reg, u8 val)
{
iowrite8(val, priv->reg_base + reg);
}
static u8 sp_read_reg16(const struct sja1000_priv *priv, int reg)
{
return ioread8(priv->reg_base + reg * 2);
}
static void sp_write_reg16(const struct sja1000_priv *priv, int reg, u8 val)
{
iowrite8(val, priv->reg_base + reg * 2);
}
static u8 sp_read_reg32(const struct sja1000_priv *priv, int reg)
{
return ioread8(priv->reg_base + reg * 4);
}
static void sp_write_reg32(const struct sja1000_priv *priv, int reg, u8 val)
{
iowrite8(val, priv->reg_base + reg * 4);
}
static void sp_populate(struct sja1000_priv *priv,
struct sja1000_platform_data *pdata,
unsigned long resource_mem_flags)
{
/* The CAN clock frequency is half the oscillator clock frequency */
priv->can.clock.freq = pdata->osc_freq / 2;
priv->ocr = pdata->ocr;
priv->cdr = pdata->cdr;
switch (resource_mem_flags & IORESOURCE_MEM_TYPE_MASK) {
case IORESOURCE_MEM_32BIT:
priv->read_reg = sp_read_reg32;
priv->write_reg = sp_write_reg32;
break;
case IORESOURCE_MEM_16BIT:
priv->read_reg = sp_read_reg16;
priv->write_reg = sp_write_reg16;
break;
case IORESOURCE_MEM_8BIT:
default:
priv->read_reg = sp_read_reg8;
priv->write_reg = sp_write_reg8;
break;
}
}
static void sp_populate_of(struct sja1000_priv *priv, struct device_node *of)
{
int err;
u32 prop;
err = of_property_read_u32(of, "reg-io-width", &prop);
if (err)
prop = 1; /* 8 bit is default */
switch (prop) {
case 4:
priv->read_reg = sp_read_reg32;
priv->write_reg = sp_write_reg32;
break;
case 2:
priv->read_reg = sp_read_reg16;
priv->write_reg = sp_write_reg16;
break;
case 1: /* fallthrough */
default:
priv->read_reg = sp_read_reg8;
priv->write_reg = sp_write_reg8;
}
err = of_property_read_u32(of, "nxp,external-clock-frequency", &prop);
if (!err)
priv->can.clock.freq = prop / 2;
else
priv->can.clock.freq = SP_CAN_CLOCK; /* default */
err = of_property_read_u32(of, "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(of, "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(of, "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(of, "nxp,no-comparator-bypass"))
priv->cdr |= CDR_CBP; /* default */
}
static int sp_probe(struct platform_device *pdev)
{
int err, irq = 0;
void __iomem *addr;
struct net_device *dev;
struct sja1000_priv *priv;
struct resource *res_mem, *res_irq = NULL;
struct sja1000_platform_data *pdata;
struct device_node *of = pdev->dev.of_node;
pdata = dev_get_platdata(&pdev->dev);
if (!pdata && !of) {
dev_err(&pdev->dev, "No platform data provided!\n");
return -ENODEV;
}
res_mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (!res_mem)
return -ENODEV;
if (!devm_request_mem_region(&pdev->dev, res_mem->start,
resource_size(res_mem), DRV_NAME))
return -EBUSY;
addr = devm_ioremap_nocache(&pdev->dev, res_mem->start,
resource_size(res_mem));
if (!addr)
return -ENOMEM;
if (of)
irq = irq_of_parse_and_map(of, 0);
else
res_irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
if (!irq && !res_irq)
return -ENODEV;
dev = alloc_sja1000dev(0);
if (!dev)
return -ENOMEM;
priv = netdev_priv(dev);
if (res_irq) {
irq = res_irq->start;
priv->irq_flags = res_irq->flags & IRQF_TRIGGER_MASK;
if (res_irq->flags & IORESOURCE_IRQ_SHAREABLE)
priv->irq_flags |= IRQF_SHARED;
} else {
priv->irq_flags = IRQF_SHARED;
}
dev->irq = irq;
priv->reg_base = addr;
if (of)
sp_populate_of(priv, of);
else
sp_populate(priv, pdata, res_mem->flags);
platform_set_drvdata(pdev, dev);
SET_NETDEV_DEV(dev, &pdev->dev);
err = register_sja1000dev(dev);
if (err) {
dev_err(&pdev->dev, "registering %s failed (err=%d)\n",
DRV_NAME, err);
goto exit_free;
}
dev_info(&pdev->dev, "%s device registered (reg_base=%p, irq=%d)\n",
DRV_NAME, priv->reg_base, dev->irq);
return 0;
exit_free:
free_sja1000dev(dev);
return err;
}
static int sp_remove(struct platform_device *pdev)
{
struct net_device *dev = platform_get_drvdata(pdev);
unregister_sja1000dev(dev);
free_sja1000dev(dev);
return 0;
}
static struct of_device_id sp_of_table[] = {
{.compatible = "nxp,sja1000"},
{},
};
MODULE_DEVICE_TABLE(of, sp_of_table);
static struct platform_driver sp_driver = {
.probe = sp_probe,
.remove = sp_remove,
.driver = {
.name = DRV_NAME,
.owner = THIS_MODULE,
.of_match_table = sp_of_table,
},
};
module_platform_driver(sp_driver);
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