1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * tscan1.c: driver for Technologic Systems TS-CAN1 PC104 boards 4 * 5 * Copyright 2010 Andre B. Oliveira 6 */ 7 8 /* 9 * References: 10 * - Getting started with TS-CAN1, Technologic Systems, Jun 2009 11 * http://www.embeddedarm.com/documentation/ts-can1-manual.pdf 12 */ 13 14 #include <linux/init.h> 15 #include <linux/io.h> 16 #include <linux/ioport.h> 17 #include <linux/isa.h> 18 #include <linux/module.h> 19 #include <linux/netdevice.h> 20 #include "sja1000.h" 21 22 MODULE_DESCRIPTION("Driver for Technologic Systems TS-CAN1 PC104 boards"); 23 MODULE_AUTHOR("Andre B. Oliveira <anbadeol@gmail.com>"); 24 MODULE_LICENSE("GPL"); 25 26 /* Maximum number of boards (one in each JP1:JP2 setting of IO address) */ 27 #define TSCAN1_MAXDEV 4 28 29 /* PLD registers address offsets */ 30 #define TSCAN1_ID1 0 31 #define TSCAN1_ID2 1 32 #define TSCAN1_VERSION 2 33 #define TSCAN1_LED 3 34 #define TSCAN1_PAGE 4 35 #define TSCAN1_MODE 5 36 #define TSCAN1_JUMPERS 6 37 38 /* PLD board identifier registers magic values */ 39 #define TSCAN1_ID1_VALUE 0xf6 40 #define TSCAN1_ID2_VALUE 0xb9 41 42 /* PLD mode register SJA1000 IO enable bit */ 43 #define TSCAN1_MODE_ENABLE 0x40 44 45 /* PLD jumpers register bits */ 46 #define TSCAN1_JP4 0x10 47 #define TSCAN1_JP5 0x20 48 49 /* PLD IO base addresses start */ 50 #define TSCAN1_PLD_ADDRESS 0x150 51 52 /* PLD register space size */ 53 #define TSCAN1_PLD_SIZE 8 54 55 /* SJA1000 register space size */ 56 #define TSCAN1_SJA1000_SIZE 32 57 58 /* SJA1000 crystal frequency (16MHz) */ 59 #define TSCAN1_SJA1000_XTAL 16000000 60 61 /* SJA1000 IO base addresses */ 62 static const unsigned short tscan1_sja1000_addresses[] = { 63 0x100, 0x120, 0x180, 0x1a0, 0x200, 0x240, 0x280, 0x320 64 }; 65 66 /* Read SJA1000 register */ 67 static u8 tscan1_read(const struct sja1000_priv *priv, int reg) 68 { 69 return inb((unsigned long)priv->reg_base + reg); 70 } 71 72 /* Write SJA1000 register */ 73 static void tscan1_write(const struct sja1000_priv *priv, int reg, u8 val) 74 { 75 outb(val, (unsigned long)priv->reg_base + reg); 76 } 77 78 /* Probe for a TS-CAN1 board with JP2:JP1 jumper setting ID */ 79 static int tscan1_probe(struct device *dev, unsigned id) 80 { 81 struct net_device *netdev; 82 struct sja1000_priv *priv; 83 unsigned long pld_base, sja1000_base; 84 int irq, i; 85 86 pld_base = TSCAN1_PLD_ADDRESS + id * TSCAN1_PLD_SIZE; 87 if (!request_region(pld_base, TSCAN1_PLD_SIZE, dev_name(dev))) 88 return -EBUSY; 89 90 if (inb(pld_base + TSCAN1_ID1) != TSCAN1_ID1_VALUE || 91 inb(pld_base + TSCAN1_ID2) != TSCAN1_ID2_VALUE) { 92 release_region(pld_base, TSCAN1_PLD_SIZE); 93 return -ENODEV; 94 } 95 96 switch (inb(pld_base + TSCAN1_JUMPERS) & (TSCAN1_JP4 | TSCAN1_JP5)) { 97 case TSCAN1_JP4: 98 irq = 6; 99 break; 100 case TSCAN1_JP5: 101 irq = 7; 102 break; 103 case TSCAN1_JP4 | TSCAN1_JP5: 104 irq = 5; 105 break; 106 default: 107 dev_err(dev, "invalid JP4:JP5 setting (no IRQ)\n"); 108 release_region(pld_base, TSCAN1_PLD_SIZE); 109 return -EINVAL; 110 } 111 112 netdev = alloc_sja1000dev(0); 113 if (!netdev) { 114 release_region(pld_base, TSCAN1_PLD_SIZE); 115 return -ENOMEM; 116 } 117 118 dev_set_drvdata(dev, netdev); 119 SET_NETDEV_DEV(netdev, dev); 120 121 netdev->base_addr = pld_base; 122 netdev->irq = irq; 123 124 priv = netdev_priv(netdev); 125 priv->read_reg = tscan1_read; 126 priv->write_reg = tscan1_write; 127 priv->can.clock.freq = TSCAN1_SJA1000_XTAL / 2; 128 priv->cdr = CDR_CBP | CDR_CLK_OFF; 129 priv->ocr = OCR_TX0_PUSHPULL; 130 131 /* Select the first SJA1000 IO address that is free and that works */ 132 for (i = 0; i < ARRAY_SIZE(tscan1_sja1000_addresses); i++) { 133 sja1000_base = tscan1_sja1000_addresses[i]; 134 if (!request_region(sja1000_base, TSCAN1_SJA1000_SIZE, 135 dev_name(dev))) 136 continue; 137 138 /* Set SJA1000 IO base address and enable it */ 139 outb(TSCAN1_MODE_ENABLE | i, pld_base + TSCAN1_MODE); 140 141 priv->reg_base = (void __iomem *)sja1000_base; 142 if (!register_sja1000dev(netdev)) { 143 /* SJA1000 probe succeeded; turn LED off and return */ 144 outb(0, pld_base + TSCAN1_LED); 145 netdev_info(netdev, "TS-CAN1 at 0x%lx 0x%lx irq %d\n", 146 pld_base, sja1000_base, irq); 147 return 0; 148 } 149 150 /* SJA1000 probe failed; release and try next address */ 151 outb(0, pld_base + TSCAN1_MODE); 152 release_region(sja1000_base, TSCAN1_SJA1000_SIZE); 153 } 154 155 dev_err(dev, "failed to assign SJA1000 IO address\n"); 156 dev_set_drvdata(dev, NULL); 157 free_sja1000dev(netdev); 158 release_region(pld_base, TSCAN1_PLD_SIZE); 159 return -ENXIO; 160 } 161 162 static void tscan1_remove(struct device *dev, unsigned id /*unused*/) 163 { 164 struct net_device *netdev; 165 struct sja1000_priv *priv; 166 unsigned long pld_base, sja1000_base; 167 168 netdev = dev_get_drvdata(dev); 169 unregister_sja1000dev(netdev); 170 dev_set_drvdata(dev, NULL); 171 172 priv = netdev_priv(netdev); 173 pld_base = netdev->base_addr; 174 sja1000_base = (unsigned long)priv->reg_base; 175 176 outb(0, pld_base + TSCAN1_MODE); /* disable SJA1000 IO space */ 177 178 release_region(sja1000_base, TSCAN1_SJA1000_SIZE); 179 release_region(pld_base, TSCAN1_PLD_SIZE); 180 181 free_sja1000dev(netdev); 182 } 183 184 static struct isa_driver tscan1_isa_driver = { 185 .probe = tscan1_probe, 186 .remove = tscan1_remove, 187 .driver = { 188 .name = "tscan1", 189 }, 190 }; 191 192 module_isa_driver(tscan1_isa_driver, TSCAN1_MAXDEV); 193