drivers/net/can/sja1000/sja1000_isa.c

   1 /*
   2  * Copyright (C) 2009 Wolfgang Grandegger <wg@grandegger.com>
   3  *
   4  * This program is free software; you can redistribute it and/or modify
   5  * it under the terms of the version 2 of the GNU General Public License
   6  * as published by the Free Software Foundation
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  11  * GNU General Public License for more details.
  12  *
  13  * You should have received a copy of the GNU General Public License
  14  * along with this program; if not, see <http://www.gnu.org/licenses/>.
  15  */
  16
  17 #include <linux/kernel.h>
  18 #include <linux/module.h>
  19 #include <linux/platform_device.h>
  20 #include <linux/interrupt.h>
  21 #include <linux/netdevice.h>
  22 #include <linux/delay.h>
  23 #include <linux/irq.h>
  24 #include <linux/io.h>
  25 #include <linux/can/dev.h>
  26 #include <linux/can/platform/sja1000.h>
  27
  28 #include "sja1000.h"
  29
  30 #define DRV_NAME "sja1000_isa"
  31
  32 #define MAXDEV 8
  33
  34 MODULE_AUTHOR("Wolfgang Grandegger <wg@grandegger.com>");
  35 MODULE_DESCRIPTION("Socket-CAN driver for SJA1000 on the ISA bus");
  36 MODULE_LICENSE("GPL v2");
  37
  38 #define CLK_DEFAULT     16000000        /* 16 MHz */
  39 #define CDR_DEFAULT     (CDR_CBP | CDR_CLK_OFF)
  40 #define OCR_DEFAULT     OCR_TX0_PUSHPULL
  41
  42 static unsigned long port[MAXDEV];
  43 static unsigned long mem[MAXDEV];
  44 static int irq[MAXDEV];
  45 static int clk[MAXDEV];
  46 static unsigned char cdr[MAXDEV] = {[0 ... (MAXDEV - 1)] = 0xff};
  47 static unsigned char ocr[MAXDEV] = {[0 ... (MAXDEV - 1)] = 0xff};
  48 static int indirect[MAXDEV] = {[0 ... (MAXDEV - 1)] = -1};
  49 static spinlock_t indirect_lock[MAXDEV];  /* lock for indirect access mode */
  50
  51 module_param_hw_array(port, ulong, ioport, NULL, 0444);
  52 MODULE_PARM_DESC(port, "I/O port number");
  53
  54 module_param_hw_array(mem, ulong, iomem, NULL, 0444);
  55 MODULE_PARM_DESC(mem, "I/O memory address");
  56
  57 module_param_hw_array(indirect, int, ioport, NULL, 0444);
  58 MODULE_PARM_DESC(indirect, "Indirect access via address and data port");
  59
  60 module_param_hw_array(irq, int, irq, NULL, 0444);
  61 MODULE_PARM_DESC(irq, "IRQ number");
  62
  63 module_param_array(clk, int, NULL, 0444);
  64 MODULE_PARM_DESC(clk, "External oscillator clock frequency "
  65                  "(default=16000000 [16 MHz])");
  66
  67 module_param_array(cdr, byte, NULL, 0444);
  68 MODULE_PARM_DESC(cdr, "Clock divider register "
  69                  "(default=0x48 [CDR_CBP | CDR_CLK_OFF])");
  70
  71 module_param_array(ocr, byte, NULL, 0444);
  72 MODULE_PARM_DESC(ocr, "Output control register "
  73                  "(default=0x18 [OCR_TX0_PUSHPULL])");
  74
  75 #define SJA1000_IOSIZE          0x20
  76 #define SJA1000_IOSIZE_INDIRECT 0x02
  77
  78 static struct platform_device *sja1000_isa_devs[MAXDEV];
  79
  80 static u8 sja1000_isa_mem_read_reg(const struct sja1000_priv *priv, int reg)
  81 {
  82         return readb(priv->reg_base + reg);
  83 }
  84
  85 static void sja1000_isa_mem_write_reg(const struct sja1000_priv *priv,
  86                                       int reg, u8 val)
  87 {
  88         writeb(val, priv->reg_base + reg);
  89 }
  90
  91 static u8 sja1000_isa_port_read_reg(const struct sja1000_priv *priv, int reg)
  92 {
  93         return inb((unsigned long)priv->reg_base + reg);
  94 }
  95
  96 static void sja1000_isa_port_write_reg(const struct sja1000_priv *priv,
  97                                        int reg, u8 val)
  98 {
  99         outb(val, (unsigned long)priv->reg_base + reg);
 100 }
 101
 102 static u8 sja1000_isa_port_read_reg_indirect(const struct sja1000_priv *priv,
 103                                              int reg)
 104 {
 105         unsigned long flags, base = (unsigned long)priv->reg_base;
 106         u8 readval;
 107
 108         spin_lock_irqsave(&indirect_lock[priv->dev->dev_id], flags);
 109         outb(reg, base);
 110         readval = inb(base + 1);
 111         spin_unlock_irqrestore(&indirect_lock[priv->dev->dev_id], flags);
 112
 113         return readval;
 114 }
 115
 116 static void sja1000_isa_port_write_reg_indirect(const struct sja1000_priv *priv,
 117                                                 int reg, u8 val)
 118 {
 119         unsigned long flags, base = (unsigned long)priv->reg_base;
 120
 121         spin_lock_irqsave(&indirect_lock[priv->dev->dev_id], flags);
 122         outb(reg, base);
 123         outb(val, base + 1);
 124         spin_unlock_irqrestore(&indirect_lock[priv->dev->dev_id], flags);
 125 }
 126
 127 static int sja1000_isa_probe(struct platform_device *pdev)
 128 {
 129         struct net_device *dev;
 130         struct sja1000_priv *priv;
 131         void __iomem *base = NULL;
 132         int iosize = SJA1000_IOSIZE;
 133         int idx = pdev->id;
 134         int err;
 135
 136         dev_dbg(&pdev->dev, "probing idx=%d: port=%#lx, mem=%#lx, irq=%d\n",
 137                 idx, port[idx], mem[idx], irq[idx]);
 138
 139         if (mem[idx]) {
 140                 if (!request_mem_region(mem[idx], iosize, DRV_NAME)) {
 141                         err = -EBUSY;
 142                         goto exit;
 143                 }
 144                 base = ioremap_nocache(mem[idx], iosize);
 145                 if (!base) {
 146                         err = -ENOMEM;
 147                         goto exit_release;
 148                 }
 149         } else {
 150                 if (indirect[idx] > 0 ||
 151                     (indirect[idx] == -1 && indirect[0] > 0))
 152                         iosize = SJA1000_IOSIZE_INDIRECT;
 153                 if (!request_region(port[idx], iosize, DRV_NAME)) {
 154                         err = -EBUSY;
 155                         goto exit;
 156                 }
 157         }
 158
 159         dev = alloc_sja1000dev(0);
 160         if (!dev) {
 161                 err = -ENOMEM;
 162                 goto exit_unmap;
 163         }
 164         priv = netdev_priv(dev);
 165
 166         dev->irq = irq[idx];
 167         priv->irq_flags = IRQF_SHARED;
 168         if (mem[idx]) {
 169                 priv->reg_base = base;
 170                 dev->base_addr = mem[idx];
 171                 priv->read_reg = sja1000_isa_mem_read_reg;
 172                 priv->write_reg = sja1000_isa_mem_write_reg;
 173         } else {
 174                 priv->reg_base = (void __iomem *)port[idx];
 175                 dev->base_addr = port[idx];
 176
 177                 if (iosize == SJA1000_IOSIZE_INDIRECT) {
 178                         priv->read_reg = sja1000_isa_port_read_reg_indirect;
 179                         priv->write_reg = sja1000_isa_port_write_reg_indirect;
 180                         spin_lock_init(&indirect_lock[idx]);
 181                 } else {
 182                         priv->read_reg = sja1000_isa_port_read_reg;
 183                         priv->write_reg = sja1000_isa_port_write_reg;
 184                 }
 185         }
 186
 187         if (clk[idx])
 188                 priv->can.clock.freq = clk[idx] / 2;
 189         else if (clk[0])
 190                 priv->can.clock.freq = clk[0] / 2;
 191         else
 192                 priv->can.clock.freq = CLK_DEFAULT / 2;
 193
 194         if (ocr[idx] != 0xff)
 195                 priv->ocr = ocr[idx];
 196         else if (ocr[0] != 0xff)
 197                 priv->ocr = ocr[0];
 198         else
 199                 priv->ocr = OCR_DEFAULT;
 200
 201         if (cdr[idx] != 0xff)
 202                 priv->cdr = cdr[idx];
 203         else if (cdr[0] != 0xff)
 204                 priv->cdr = cdr[0];
 205         else
 206                 priv->cdr = CDR_DEFAULT;
 207
 208         platform_set_drvdata(pdev, dev);
 209         SET_NETDEV_DEV(dev, &pdev->dev);
 210         dev->dev_id = idx;
 211
 212         err = register_sja1000dev(dev);
 213         if (err) {
 214                 dev_err(&pdev->dev, "registering %s failed (err=%d)\n",
 215                         DRV_NAME, err);
 216                 goto exit_free;
 217         }
 218
 219         dev_info(&pdev->dev, "%s device registered (reg_base=0x%p, irq=%d)\n",
 220                  DRV_NAME, priv->reg_base, dev->irq);
 221         return 0;
 222
 223 exit_free:
 224         free_sja1000dev(dev);
 225 exit_unmap:
 226         if (mem[idx])
 227                 iounmap(base);
 228 exit_release:
 229         if (mem[idx])
 230                 release_mem_region(mem[idx], iosize);
 231         else
 232                 release_region(port[idx], iosize);
 233 exit:
 234         return err;
 235 }
 236
 237 static int sja1000_isa_remove(struct platform_device *pdev)
 238 {
 239         struct net_device *dev = platform_get_drvdata(pdev);
 240         struct sja1000_priv *priv = netdev_priv(dev);
 241         int idx = pdev->id;
 242
 243         unregister_sja1000dev(dev);
 244
 245         if (mem[idx]) {
 246                 iounmap(priv->reg_base);
 247                 release_mem_region(mem[idx], SJA1000_IOSIZE);
 248         } else {
 249                 if (priv->read_reg == sja1000_isa_port_read_reg_indirect)
 250                         release_region(port[idx], SJA1000_IOSIZE_INDIRECT);
 251                 else
 252                         release_region(port[idx], SJA1000_IOSIZE);
 253         }
 254         free_sja1000dev(dev);
 255
 256         return 0;
 257 }
 258
 259 static struct platform_driver sja1000_isa_driver = {
 260         .probe = sja1000_isa_probe,
 261         .remove = sja1000_isa_remove,
 262         .driver = {
 263                 .name = DRV_NAME,
 264         },
 265 };
 266
 267 static int __init sja1000_isa_init(void)
 268 {
 269         int idx, err;
 270
 271         for (idx = 0; idx < MAXDEV; idx++) {
 272                 if ((port[idx] || mem[idx]) && irq[idx]) {
 273                         sja1000_isa_devs[idx] =
 274                                 platform_device_alloc(DRV_NAME, idx);
 275                         if (!sja1000_isa_devs[idx]) {
 276                                 err = -ENOMEM;
 277                                 goto exit_free_devices;
 278                         }
 279                         err = platform_device_add(sja1000_isa_devs[idx]);
 280                         if (err) {
 281                                 platform_device_put(sja1000_isa_devs[idx]);
 282                                 goto exit_free_devices;
 283                         }
 284                         pr_debug("%s: platform device %d: port=%#lx, mem=%#lx, "
 285                                  "irq=%d\n",
 286                                  DRV_NAME, idx, port[idx], mem[idx], irq[idx]);
 287                 } else if (idx == 0 || port[idx] || mem[idx]) {
 288                                 pr_err("%s: insufficient parameters supplied\n",
 289                                        DRV_NAME);
 290                                 err = -EINVAL;
 291                                 goto exit_free_devices;
 292                 }
 293         }
 294
 295         err = platform_driver_register(&sja1000_isa_driver);
 296         if (err)
 297                 goto exit_free_devices;
 298
 299         pr_info("Legacy %s driver for max. %d devices registered\n",
 300                 DRV_NAME, MAXDEV);
 301
 302         return 0;
 303
 304 exit_free_devices:
 305         while (--idx >= 0) {
 306                 if (sja1000_isa_devs[idx])
 307                         platform_device_unregister(sja1000_isa_devs[idx]);
 308         }
 309
 310         return err;
 311 }
 312
 313 static void __exit sja1000_isa_exit(void)
 314 {
 315         int idx;
 316
 317         platform_driver_unregister(&sja1000_isa_driver);
 318         for (idx = 0; idx < MAXDEV; idx++) {
 319                 if (sja1000_isa_devs[idx])
 320                         platform_device_unregister(sja1000_isa_devs[idx]);
 321         }
 322 }
 323
 324 module_init(sja1000_isa_init);
 325 module_exit(sja1000_isa_exit);