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
cc770_isa_mem_read_reg(const struct cc770_priv * priv,int reg)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
cc770_isa_mem_write_reg(const struct cc770_priv * priv,int reg,u8 val)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
cc770_isa_port_read_reg(const struct cc770_priv * priv,int reg)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
cc770_isa_port_write_reg(const struct cc770_priv * priv,int reg,u8 val)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
cc770_isa_port_read_reg_indirect(const struct cc770_priv * priv,int reg)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
cc770_isa_port_write_reg_indirect(const struct cc770_priv * priv,int reg,u8 val)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
cc770_isa_probe(struct platform_device * pdev)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
cc770_isa_remove(struct platform_device * pdev)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
cc770_isa_init(void)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
cc770_isa_exit(void)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