1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Driver for CC770 and AN82527 CAN controllers on the legacy ISA bus 4 * 5 * Copyright (C) 2009, 2011 Wolfgang Grandegger <wg@grandegger.com> 6 */ 7 8 /* 9 * Bosch CC770 and Intel AN82527 CAN controllers on the ISA or PC-104 bus. 10 * The I/O port or memory address and the IRQ number must be specified via 11 * module parameters: 12 * 13 * insmod cc770_isa.ko port=0x310,0x380 irq=7,11 14 * 15 * for ISA devices using I/O ports or: 16 * 17 * insmod cc770_isa.ko mem=0xd1000,0xd1000 irq=7,11 18 * 19 * for memory mapped ISA devices. 20 * 21 * Indirect access via address and data port is supported as well: 22 * 23 * insmod cc770_isa.ko port=0x310,0x380 indirect=1 irq=7,11 24 * 25 * Furthermore, the following mode parameter can be defined: 26 * 27 * clk: External oscillator clock frequency (default=16000000 [16 MHz]) 28 * cir: CPU interface register (default=0x40 [DSC]) 29 * bcr: Bus configuration register (default=0x40 [CBY]) 30 * cor: Clockout register (default=0x00) 31 * 32 * Note: for clk, cir, bcr and cor, the first argument re-defines the 33 * default for all other devices, e.g.: 34 * 35 * insmod cc770_isa.ko mem=0xd1000,0xd1000 irq=7,11 clk=24000000 36 * 37 * is equivalent to 38 * 39 * insmod cc770_isa.ko mem=0xd1000,0xd1000 irq=7,11 clk=24000000,24000000 40 */ 41 42 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 43 44 #include <linux/kernel.h> 45 #include <linux/module.h> 46 #include <linux/platform_device.h> 47 #include <linux/interrupt.h> 48 #include <linux/netdevice.h> 49 #include <linux/delay.h> 50 #include <linux/irq.h> 51 #include <linux/io.h> 52 #include <linux/can.h> 53 #include <linux/can/dev.h> 54 #include <linux/can/platform/cc770.h> 55 56 #include "cc770.h" 57 58 #define MAXDEV 8 59 60 MODULE_AUTHOR("Wolfgang Grandegger <wg@grandegger.com>"); 61 MODULE_DESCRIPTION("Socket-CAN driver for CC770 on the ISA bus"); 62 MODULE_LICENSE("GPL v2"); 63 64 #define CLK_DEFAULT 16000000 /* 16 MHz */ 65 #define COR_DEFAULT 0x00 66 #define BCR_DEFAULT BUSCFG_CBY 67 68 static unsigned long port[MAXDEV]; 69 static unsigned long mem[MAXDEV]; 70 static int irq[MAXDEV]; 71 static int clk[MAXDEV]; 72 static u8 cir[MAXDEV] = {[0 ... (MAXDEV - 1)] = 0xff}; 73 static u8 cor[MAXDEV] = {[0 ... (MAXDEV - 1)] = 0xff}; 74 static u8 bcr[MAXDEV] = {[0 ... (MAXDEV - 1)] = 0xff}; 75 static int indirect[MAXDEV] = {[0 ... (MAXDEV - 1)] = -1}; 76 77 module_param_hw_array(port, ulong, ioport, NULL, 0444); 78 MODULE_PARM_DESC(port, "I/O port number"); 79 80 module_param_hw_array(mem, ulong, iomem, NULL, 0444); 81 MODULE_PARM_DESC(mem, "I/O memory address"); 82 83 module_param_hw_array(indirect, int, ioport, NULL, 0444); 84 MODULE_PARM_DESC(indirect, "Indirect access via address and data port"); 85 86 module_param_hw_array(irq, int, irq, NULL, 0444); 87 MODULE_PARM_DESC(irq, "IRQ number"); 88 89 module_param_array(clk, int, NULL, 0444); 90 MODULE_PARM_DESC(clk, "External oscillator clock frequency " 91 "(default=16000000 [16 MHz])"); 92 93 module_param_array(cir, byte, NULL, 0444); 94 MODULE_PARM_DESC(cir, "CPU interface register (default=0x40 [DSC])"); 95 96 module_param_array(cor, byte, NULL, 0444); 97 MODULE_PARM_DESC(cor, "Clockout register (default=0x00)"); 98 99 module_param_array(bcr, byte, NULL, 0444); 100 MODULE_PARM_DESC(bcr, "Bus configuration register (default=0x40 [CBY])"); 101 102 #define CC770_IOSIZE 0x20 103 #define CC770_IOSIZE_INDIRECT 0x02 104 105 /* Spinlock for cc770_isa_port_write_reg_indirect 106 * and cc770_isa_port_read_reg_indirect 107 */ 108 static DEFINE_SPINLOCK(cc770_isa_port_lock); 109 110 static struct platform_device *cc770_isa_devs[MAXDEV]; 111 112 static u8 cc770_isa_mem_read_reg(const struct cc770_priv *priv, int reg) 113 { 114 return readb(priv->reg_base + reg); 115 } 116 117 static void cc770_isa_mem_write_reg(const struct cc770_priv *priv, 118 int reg, u8 val) 119 { 120 writeb(val, priv->reg_base + reg); 121 } 122 123 static u8 cc770_isa_port_read_reg(const struct cc770_priv *priv, int reg) 124 { 125 return inb((unsigned long)priv->reg_base + reg); 126 } 127 128 static void cc770_isa_port_write_reg(const struct cc770_priv *priv, 129 int reg, u8 val) 130 { 131 outb(val, (unsigned long)priv->reg_base + reg); 132 } 133 134 static u8 cc770_isa_port_read_reg_indirect(const struct cc770_priv *priv, 135 int reg) 136 { 137 unsigned long base = (unsigned long)priv->reg_base; 138 unsigned long flags; 139 u8 val; 140 141 spin_lock_irqsave(&cc770_isa_port_lock, flags); 142 outb(reg, base); 143 val = inb(base + 1); 144 spin_unlock_irqrestore(&cc770_isa_port_lock, flags); 145 146 return val; 147 } 148 149 static void cc770_isa_port_write_reg_indirect(const struct cc770_priv *priv, 150 int reg, u8 val) 151 { 152 unsigned long base = (unsigned long)priv->reg_base; 153 unsigned long flags; 154 155 spin_lock_irqsave(&cc770_isa_port_lock, flags); 156 outb(reg, base); 157 outb(val, base + 1); 158 spin_unlock_irqrestore(&cc770_isa_port_lock, flags); 159 } 160 161 static int cc770_isa_probe(struct platform_device *pdev) 162 { 163 struct net_device *dev; 164 struct cc770_priv *priv; 165 void __iomem *base = NULL; 166 int iosize = CC770_IOSIZE; 167 int idx = pdev->id; 168 int err; 169 u32 clktmp; 170 171 dev_dbg(&pdev->dev, "probing idx=%d: port=%#lx, mem=%#lx, irq=%d\n", 172 idx, port[idx], mem[idx], irq[idx]); 173 if (mem[idx]) { 174 if (!request_mem_region(mem[idx], iosize, KBUILD_MODNAME)) { 175 err = -EBUSY; 176 goto exit; 177 } 178 base = ioremap(mem[idx], iosize); 179 if (!base) { 180 err = -ENOMEM; 181 goto exit_release; 182 } 183 } else { 184 if (indirect[idx] > 0 || 185 (indirect[idx] == -1 && indirect[0] > 0)) 186 iosize = CC770_IOSIZE_INDIRECT; 187 if (!request_region(port[idx], iosize, KBUILD_MODNAME)) { 188 err = -EBUSY; 189 goto exit; 190 } 191 } 192 193 dev = alloc_cc770dev(0); 194 if (!dev) { 195 err = -ENOMEM; 196 goto exit_unmap; 197 } 198 priv = netdev_priv(dev); 199 200 dev->irq = irq[idx]; 201 priv->irq_flags = IRQF_SHARED; 202 if (mem[idx]) { 203 priv->reg_base = base; 204 dev->base_addr = mem[idx]; 205 priv->read_reg = cc770_isa_mem_read_reg; 206 priv->write_reg = cc770_isa_mem_write_reg; 207 } else { 208 priv->reg_base = (void __iomem *)port[idx]; 209 dev->base_addr = port[idx]; 210 211 if (iosize == CC770_IOSIZE_INDIRECT) { 212 priv->read_reg = cc770_isa_port_read_reg_indirect; 213 priv->write_reg = cc770_isa_port_write_reg_indirect; 214 } else { 215 priv->read_reg = cc770_isa_port_read_reg; 216 priv->write_reg = cc770_isa_port_write_reg; 217 } 218 } 219 220 if (clk[idx]) 221 clktmp = clk[idx]; 222 else if (clk[0]) 223 clktmp = clk[0]; 224 else 225 clktmp = CLK_DEFAULT; 226 priv->can.clock.freq = clktmp; 227 228 if (cir[idx] != 0xff) { 229 priv->cpu_interface = cir[idx]; 230 } else if (cir[0] != 0xff) { 231 priv->cpu_interface = cir[0]; 232 } else { 233 /* The system clock may not exceed 10 MHz */ 234 if (clktmp > 10000000) { 235 priv->cpu_interface |= CPUIF_DSC; 236 clktmp /= 2; 237 } 238 /* The memory clock may not exceed 8 MHz */ 239 if (clktmp > 8000000) 240 priv->cpu_interface |= CPUIF_DMC; 241 } 242 243 if (priv->cpu_interface & CPUIF_DSC) 244 priv->can.clock.freq /= 2; 245 246 if (bcr[idx] != 0xff) 247 priv->bus_config = bcr[idx]; 248 else if (bcr[0] != 0xff) 249 priv->bus_config = bcr[0]; 250 else 251 priv->bus_config = BCR_DEFAULT; 252 253 if (cor[idx] != 0xff) 254 priv->clkout = cor[idx]; 255 else if (cor[0] != 0xff) 256 priv->clkout = cor[0]; 257 else 258 priv->clkout = COR_DEFAULT; 259 260 platform_set_drvdata(pdev, dev); 261 SET_NETDEV_DEV(dev, &pdev->dev); 262 263 err = register_cc770dev(dev); 264 if (err) { 265 dev_err(&pdev->dev, 266 "couldn't register device (err=%d)\n", err); 267 goto exit_free; 268 } 269 270 dev_info(&pdev->dev, "device registered (reg_base=0x%p, irq=%d)\n", 271 priv->reg_base, dev->irq); 272 return 0; 273 274 exit_free: 275 free_cc770dev(dev); 276 exit_unmap: 277 if (mem[idx]) 278 iounmap(base); 279 exit_release: 280 if (mem[idx]) 281 release_mem_region(mem[idx], iosize); 282 else 283 release_region(port[idx], iosize); 284 exit: 285 return err; 286 } 287 288 static void cc770_isa_remove(struct platform_device *pdev) 289 { 290 struct net_device *dev = platform_get_drvdata(pdev); 291 struct cc770_priv *priv = netdev_priv(dev); 292 int idx = pdev->id; 293 294 unregister_cc770dev(dev); 295 296 if (mem[idx]) { 297 iounmap(priv->reg_base); 298 release_mem_region(mem[idx], CC770_IOSIZE); 299 } else { 300 if (priv->read_reg == cc770_isa_port_read_reg_indirect) 301 release_region(port[idx], CC770_IOSIZE_INDIRECT); 302 else 303 release_region(port[idx], CC770_IOSIZE); 304 } 305 free_cc770dev(dev); 306 } 307 308 static struct platform_driver cc770_isa_driver = { 309 .probe = cc770_isa_probe, 310 .remove_new = cc770_isa_remove, 311 .driver = { 312 .name = KBUILD_MODNAME, 313 }, 314 }; 315 316 static int __init cc770_isa_init(void) 317 { 318 int idx, err; 319 320 for (idx = 0; idx < ARRAY_SIZE(cc770_isa_devs); idx++) { 321 if ((port[idx] || mem[idx]) && irq[idx]) { 322 cc770_isa_devs[idx] = 323 platform_device_alloc(KBUILD_MODNAME, idx); 324 if (!cc770_isa_devs[idx]) { 325 err = -ENOMEM; 326 goto exit_free_devices; 327 } 328 err = platform_device_add(cc770_isa_devs[idx]); 329 if (err) { 330 platform_device_put(cc770_isa_devs[idx]); 331 goto exit_free_devices; 332 } 333 pr_debug("platform device %d: port=%#lx, mem=%#lx, " 334 "irq=%d\n", 335 idx, port[idx], mem[idx], irq[idx]); 336 } else if (idx == 0 || port[idx] || mem[idx]) { 337 pr_err("insufficient parameters supplied\n"); 338 err = -EINVAL; 339 goto exit_free_devices; 340 } 341 } 342 343 err = platform_driver_register(&cc770_isa_driver); 344 if (err) 345 goto exit_free_devices; 346 347 pr_info("driver for max. %d devices registered\n", MAXDEV); 348 349 return 0; 350 351 exit_free_devices: 352 while (--idx >= 0) { 353 if (cc770_isa_devs[idx]) 354 platform_device_unregister(cc770_isa_devs[idx]); 355 } 356 357 return err; 358 } 359 module_init(cc770_isa_init); 360 361 static void __exit cc770_isa_exit(void) 362 { 363 int idx; 364 365 platform_driver_unregister(&cc770_isa_driver); 366 for (idx = 0; idx < ARRAY_SIZE(cc770_isa_devs); idx++) { 367 if (cc770_isa_devs[idx]) 368 platform_device_unregister(cc770_isa_devs[idx]); 369 } 370 } 371 module_exit(cc770_isa_exit); 372