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Release 4.11 drivers/net/can/sja1000/tscan1.c

/*
 * tscan1.c: driver for Technologic Systems TS-CAN1 PC104 boards
 *
 * Copyright 2010 Andre B. Oliveira
 *
 * 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, see <http://www.gnu.org/licenses/>.
 */

/*
 * References:
 * - Getting started with TS-CAN1, Technologic Systems, Jun 2009
 *      http://www.embeddedarm.com/documentation/ts-can1-manual.pdf
 */

#include <linux/init.h>
#include <linux/io.h>
#include <linux/ioport.h>
#include <linux/isa.h>
#include <linux/module.h>
#include <linux/netdevice.h>
#include "sja1000.h"

MODULE_DESCRIPTION("Driver for Technologic Systems TS-CAN1 PC104 boards");
MODULE_AUTHOR("Andre B. Oliveira <anbadeol@gmail.com>");
MODULE_LICENSE("GPL");

/* Maximum number of boards (one in each JP1:JP2 setting of IO address) */

#define TSCAN1_MAXDEV 4

/* PLD registers address offsets */

#define TSCAN1_ID1	0

#define TSCAN1_ID2	1

#define TSCAN1_VERSION	2

#define TSCAN1_LED	3

#define TSCAN1_PAGE	4

#define TSCAN1_MODE	5

#define TSCAN1_JUMPERS	6

/* PLD board identifier registers magic values */

#define TSCAN1_ID1_VALUE 0xf6

#define TSCAN1_ID2_VALUE 0xb9

/* PLD mode register SJA1000 IO enable bit */

#define TSCAN1_MODE_ENABLE 0x40

/* PLD jumpers register bits */

#define TSCAN1_JP4 0x10

#define TSCAN1_JP5 0x20

/* PLD IO base addresses start */

#define TSCAN1_PLD_ADDRESS 0x150

/* PLD register space size */

#define TSCAN1_PLD_SIZE 8

/* SJA1000 register space size */

#define TSCAN1_SJA1000_SIZE 32

/* SJA1000 crystal frequency (16MHz) */

#define TSCAN1_SJA1000_XTAL 16000000

/* SJA1000 IO base addresses */

static const unsigned short tscan1_sja1000_addresses[] = {
	0x100, 0x120, 0x180, 0x1a0, 0x200, 0x240, 0x280, 0x320
};

/* Read SJA1000 register */

static u8 tscan1_read(const struct sja1000_priv *priv, int reg) { return inb((unsigned long)priv->reg_base + reg); }

Contributors

PersonTokensPropCommitsCommitProp
Andre B. Oliveira29100.00%1100.00%
Total29100.00%1100.00%

/* Write SJA1000 register */
static void tscan1_write(const struct sja1000_priv *priv, int reg, u8 val) { outb(val, (unsigned long)priv->reg_base + reg); }

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Andre B. Oliveira33100.00%1100.00%
Total33100.00%1100.00%

/* Probe for a TS-CAN1 board with JP2:JP1 jumper setting ID */
static int tscan1_probe(struct device *dev, unsigned id) { struct net_device *netdev; struct sja1000_priv *priv; unsigned long pld_base, sja1000_base; int irq, i; pld_base = TSCAN1_PLD_ADDRESS + id * TSCAN1_PLD_SIZE; if (!request_region(pld_base, TSCAN1_PLD_SIZE, dev_name(dev))) return -EBUSY; if (inb(pld_base + TSCAN1_ID1) != TSCAN1_ID1_VALUE || inb(pld_base + TSCAN1_ID2) != TSCAN1_ID2_VALUE) { release_region(pld_base, TSCAN1_PLD_SIZE); return -ENODEV; } switch (inb(pld_base + TSCAN1_JUMPERS) & (TSCAN1_JP4 | TSCAN1_JP5)) { case TSCAN1_JP4: irq = 6; break; case TSCAN1_JP5: irq = 7; break; case TSCAN1_JP4 | TSCAN1_JP5: irq = 5; break; default: dev_err(dev, "invalid JP4:JP5 setting (no IRQ)\n"); release_region(pld_base, TSCAN1_PLD_SIZE); return -EINVAL; } netdev = alloc_sja1000dev(0); if (!netdev) { release_region(pld_base, TSCAN1_PLD_SIZE); return -ENOMEM; } dev_set_drvdata(dev, netdev); SET_NETDEV_DEV(netdev, dev); netdev->base_addr = pld_base; netdev->irq = irq; priv = netdev_priv(netdev); priv->read_reg = tscan1_read; priv->write_reg = tscan1_write; priv->can.clock.freq = TSCAN1_SJA1000_XTAL / 2; priv->cdr = CDR_CBP | CDR_CLK_OFF; priv->ocr = OCR_TX0_PUSHPULL; /* Select the first SJA1000 IO address that is free and that works */ for (i = 0; i < ARRAY_SIZE(tscan1_sja1000_addresses); i++) { sja1000_base = tscan1_sja1000_addresses[i]; if (!request_region(sja1000_base, TSCAN1_SJA1000_SIZE, dev_name(dev))) continue; /* Set SJA1000 IO base address and enable it */ outb(TSCAN1_MODE_ENABLE | i, pld_base + TSCAN1_MODE); priv->reg_base = (void __iomem *)sja1000_base; if (!register_sja1000dev(netdev)) { /* SJA1000 probe succeeded; turn LED off and return */ outb(0, pld_base + TSCAN1_LED); netdev_info(netdev, "TS-CAN1 at 0x%lx 0x%lx irq %d\n", pld_base, sja1000_base, irq); return 0; } /* SJA1000 probe failed; release and try next address */ outb(0, pld_base + TSCAN1_MODE); release_region(sja1000_base, TSCAN1_SJA1000_SIZE); } dev_err(dev, "failed to assign SJA1000 IO address\n"); dev_set_drvdata(dev, NULL); free_sja1000dev(netdev); release_region(pld_base, TSCAN1_PLD_SIZE); return -ENXIO; }

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Andre B. Oliveira401100.00%1100.00%
Total401100.00%1100.00%


static int tscan1_remove(struct device *dev, unsigned id /*unused*/) { struct net_device *netdev; struct sja1000_priv *priv; unsigned long pld_base, sja1000_base; netdev = dev_get_drvdata(dev); unregister_sja1000dev(netdev); dev_set_drvdata(dev, NULL); priv = netdev_priv(netdev); pld_base = netdev->base_addr; sja1000_base = (unsigned long)priv->reg_base; outb(0, pld_base + TSCAN1_MODE); /* disable SJA1000 IO space */ release_region(sja1000_base, TSCAN1_SJA1000_SIZE); release_region(pld_base, TSCAN1_PLD_SIZE); free_sja1000dev(netdev); return 0; }

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PersonTokensPropCommitsCommitProp
Andre B. Oliveira105100.00%1100.00%
Total105100.00%1100.00%

static struct isa_driver tscan1_isa_driver = { .probe = tscan1_probe, .remove = tscan1_remove, .driver = { .name = "tscan1", }, }; module_isa_driver(tscan1_isa_driver, TSCAN1_MAXDEV);

Overall Contributors

PersonTokensPropCommitsCommitProp
Andre B. Oliveira74599.87%150.00%
William Breathitt Gray10.13%150.00%
Bill Pemberton0.00%00.00%
Total746100.00%2100.00%
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