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1// SPDX-License-Identifier: GPL-2.0-or-later2/*3 * tscan1.c: driver for Technologic Systems TS-CAN1 PC104 boards4 *5 * Copyright 2010 Andre B. Oliveira6 */7 8/* References:9 * - Getting started with TS-CAN1, Technologic Systems, Feb 202210 * https://docs.embeddedts.com/TS-CAN111 */12 13#include <linux/init.h>14#include <linux/io.h>15#include <linux/ioport.h>16#include <linux/isa.h>17#include <linux/module.h>18#include <linux/netdevice.h>19#include "sja1000.h"20 21MODULE_DESCRIPTION("Driver for Technologic Systems TS-CAN1 PC104 boards");22MODULE_AUTHOR("Andre B. Oliveira <anbadeol@gmail.com>");23MODULE_LICENSE("GPL");24 25/* Maximum number of boards (one in each JP1:JP2 setting of IO address) */26#define TSCAN1_MAXDEV 427 28/* PLD registers address offsets */29#define TSCAN1_ID1 030#define TSCAN1_ID2 131#define TSCAN1_VERSION 232#define TSCAN1_LED 333#define TSCAN1_PAGE 434#define TSCAN1_MODE 535#define TSCAN1_JUMPERS 636 37/* PLD board identifier registers magic values */38#define TSCAN1_ID1_VALUE 0xf639#define TSCAN1_ID2_VALUE 0xb940 41/* PLD mode register SJA1000 IO enable bit */42#define TSCAN1_MODE_ENABLE 0x4043 44/* PLD jumpers register bits */45#define TSCAN1_JP4 0x1046#define TSCAN1_JP5 0x2047 48/* PLD IO base addresses start */49#define TSCAN1_PLD_ADDRESS 0x15050 51/* PLD register space size */52#define TSCAN1_PLD_SIZE 853 54/* SJA1000 register space size */55#define TSCAN1_SJA1000_SIZE 3256 57/* SJA1000 crystal frequency (16MHz) */58#define TSCAN1_SJA1000_XTAL 1600000059 60/* SJA1000 IO base addresses */61static const unsigned short tscan1_sja1000_addresses[] = {62 0x100, 0x120, 0x180, 0x1a0, 0x200, 0x240, 0x280, 0x32063};64 65/* Read SJA1000 register */66static u8 tscan1_read(const struct sja1000_priv *priv, int reg)67{68 return inb((unsigned long)priv->reg_base + reg);69}70 71/* Write SJA1000 register */72static void tscan1_write(const struct sja1000_priv *priv, int reg, u8 val)73{74 outb(val, (unsigned long)priv->reg_base + reg);75}76 77/* Probe for a TS-CAN1 board with JP2:JP1 jumper setting ID */78static int tscan1_probe(struct device *dev, unsigned id)79{80 struct net_device *netdev;81 struct sja1000_priv *priv;82 unsigned long pld_base, sja1000_base;83 int irq, i;84 85 pld_base = TSCAN1_PLD_ADDRESS + id * TSCAN1_PLD_SIZE;86 if (!request_region(pld_base, TSCAN1_PLD_SIZE, dev_name(dev)))87 return -EBUSY;88 89 if (inb(pld_base + TSCAN1_ID1) != TSCAN1_ID1_VALUE ||90 inb(pld_base + TSCAN1_ID2) != TSCAN1_ID2_VALUE) {91 release_region(pld_base, TSCAN1_PLD_SIZE);92 return -ENODEV;93 }94 95 switch (inb(pld_base + TSCAN1_JUMPERS) & (TSCAN1_JP4 | TSCAN1_JP5)) {96 case TSCAN1_JP4:97 irq = 6;98 break;99 case TSCAN1_JP5:100 irq = 7;101 break;102 case TSCAN1_JP4 | TSCAN1_JP5:103 irq = 5;104 break;105 default:106 dev_err(dev, "invalid JP4:JP5 setting (no IRQ)\n");107 release_region(pld_base, TSCAN1_PLD_SIZE);108 return -EINVAL;109 }110 111 netdev = alloc_sja1000dev(0);112 if (!netdev) {113 release_region(pld_base, TSCAN1_PLD_SIZE);114 return -ENOMEM;115 }116 117 dev_set_drvdata(dev, netdev);118 SET_NETDEV_DEV(netdev, dev);119 120 netdev->base_addr = pld_base;121 netdev->irq = irq;122 123 priv = netdev_priv(netdev);124 priv->read_reg = tscan1_read;125 priv->write_reg = tscan1_write;126 priv->can.clock.freq = TSCAN1_SJA1000_XTAL / 2;127 priv->cdr = CDR_CBP | CDR_CLK_OFF;128 priv->ocr = OCR_TX0_PUSHPULL;129 130 /* Select the first SJA1000 IO address that is free and that works */131 for (i = 0; i < ARRAY_SIZE(tscan1_sja1000_addresses); i++) {132 sja1000_base = tscan1_sja1000_addresses[i];133 if (!request_region(sja1000_base, TSCAN1_SJA1000_SIZE,134 dev_name(dev)))135 continue;136 137 /* Set SJA1000 IO base address and enable it */138 outb(TSCAN1_MODE_ENABLE | i, pld_base + TSCAN1_MODE);139 140 priv->reg_base = (void __iomem *)sja1000_base;141 if (!register_sja1000dev(netdev)) {142 /* SJA1000 probe succeeded; turn LED off and return */143 outb(0, pld_base + TSCAN1_LED);144 netdev_info(netdev, "TS-CAN1 at 0x%lx 0x%lx irq %d\n",145 pld_base, sja1000_base, irq);146 return 0;147 }148 149 /* SJA1000 probe failed; release and try next address */150 outb(0, pld_base + TSCAN1_MODE);151 release_region(sja1000_base, TSCAN1_SJA1000_SIZE);152 }153 154 dev_err(dev, "failed to assign SJA1000 IO address\n");155 dev_set_drvdata(dev, NULL);156 free_sja1000dev(netdev);157 release_region(pld_base, TSCAN1_PLD_SIZE);158 return -ENXIO;159}160 161static void tscan1_remove(struct device *dev, unsigned id /*unused*/)162{163 struct net_device *netdev;164 struct sja1000_priv *priv;165 unsigned long pld_base, sja1000_base;166 167 netdev = dev_get_drvdata(dev);168 unregister_sja1000dev(netdev);169 dev_set_drvdata(dev, NULL);170 171 priv = netdev_priv(netdev);172 pld_base = netdev->base_addr;173 sja1000_base = (unsigned long)priv->reg_base;174 175 outb(0, pld_base + TSCAN1_MODE); /* disable SJA1000 IO space */176 177 release_region(sja1000_base, TSCAN1_SJA1000_SIZE);178 release_region(pld_base, TSCAN1_PLD_SIZE);179 180 free_sja1000dev(netdev);181}182 183static struct isa_driver tscan1_isa_driver = {184 .probe = tscan1_probe,185 .remove = tscan1_remove,186 .driver = {187 .name = "tscan1",188 },189};190 191module_isa_driver(tscan1_isa_driver, TSCAN1_MAXDEV);192