diff options
Diffstat (limited to 'drivers/net/can/sja1000/tscan1.c')
| -rw-r--r-- | drivers/net/can/sja1000/tscan1.c | 206 |
1 files changed, 206 insertions, 0 deletions
diff --git a/drivers/net/can/sja1000/tscan1.c b/drivers/net/can/sja1000/tscan1.c new file mode 100644 index 000000000..79572457a --- /dev/null +++ b/drivers/net/can/sja1000/tscan1.c @@ -0,0 +1,206 @@ +/* + * 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); +} + +/* Write SJA1000 register */ +static void tscan1_write(const struct sja1000_priv *priv, int reg, u8 val) +{ + outb(val, (unsigned long)priv->reg_base + reg); +} + +/* 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; +} + +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; +} + +static struct isa_driver tscan1_isa_driver = { + .probe = tscan1_probe, + .remove = tscan1_remove, + .driver = { + .name = "tscan1", + }, +}; + +module_isa_driver(tscan1_isa_driver, TSCAN1_MAXDEV); |