| // SPDX-License-Identifier: GPL-2.0-or-later |
| /* |
| * tscan1.c: driver for Technologic Systems TS-CAN1 PC104 boards |
| * |
| * Copyright 2010 Andre B. Oliveira |
| */ |
| |
| /* References: |
| * - Getting started with TS-CAN1, Technologic Systems, Feb 2022 |
| * https://docs.embeddedts.com/TS-CAN1 |
| */ |
| |
| #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 void 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); |
| } |
| |
| static struct isa_driver tscan1_isa_driver = { |
| .probe = tscan1_probe, |
| .remove = tscan1_remove, |
| .driver = { |
| .name = "tscan1", |
| }, |
| }; |
| |
| module_isa_driver(tscan1_isa_driver, TSCAN1_MAXDEV); |