sja1000_isa.c revision 05780d9808f72dc28a5c3602e11a7c53aef972ad 
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
34MODULE_AUTHOR("Wolfgang Grandegger <wg@grandegger.com>");
35MODULE_DESCRIPTION("Socket-CAN driver for SJA1000 on the ISA bus");
36MODULE_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
42static unsigned long port[MAXDEV];
43static unsigned long mem[MAXDEV];
44static int irq[MAXDEV];
45static int clk[MAXDEV];
46static unsigned char cdr[MAXDEV] = {[0 ... (MAXDEV - 1)] = 0xff};
47static unsigned char ocr[MAXDEV] = {[0 ... (MAXDEV - 1)] = 0xff};
48static int indirect[MAXDEV] = {[0 ... (MAXDEV - 1)] = -1};
49
50module_param_array(port, ulong, NULL, S_IRUGO);
51MODULE_PARM_DESC(port, "I/O port number");
52
53module_param_array(mem, ulong, NULL, S_IRUGO);
54MODULE_PARM_DESC(mem, "I/O memory address");
55
56module_param_array(indirect, int, NULL, S_IRUGO);
57MODULE_PARM_DESC(indirect, "Indirect access via address and data port");
58
59module_param_array(irq, int, NULL, S_IRUGO);
60MODULE_PARM_DESC(irq, "IRQ number");
61
62module_param_array(clk, int, NULL, S_IRUGO);
63MODULE_PARM_DESC(clk, "External oscillator clock frequency "
64		 "(default=16000000 [16 MHz])");
65
66module_param_array(cdr, byte, NULL, S_IRUGO);
67MODULE_PARM_DESC(cdr, "Clock divider register "
68		 "(default=0x48 [CDR_CBP | CDR_CLK_OFF])");
69
70module_param_array(ocr, byte, NULL, S_IRUGO);
71MODULE_PARM_DESC(ocr, "Output control register "
72		 "(default=0x18 [OCR_TX0_PUSHPULL])");
73
74#define SJA1000_IOSIZE          0x20
75#define SJA1000_IOSIZE_INDIRECT 0x02
76
77static struct platform_device *sja1000_isa_devs[MAXDEV];
78
79static u8 sja1000_isa_mem_read_reg(const struct sja1000_priv *priv, int reg)
80{
81	return readb(priv->reg_base + reg);
82}
83
84static void sja1000_isa_mem_write_reg(const struct sja1000_priv *priv,
85				      int reg, u8 val)
86{
87	writeb(val, priv->reg_base + reg);
88}
89
90static u8 sja1000_isa_port_read_reg(const struct sja1000_priv *priv, int reg)
91{
92	return inb((unsigned long)priv->reg_base + reg);
93}
94
95static void sja1000_isa_port_write_reg(const struct sja1000_priv *priv,
96				       int reg, u8 val)
97{
98	outb(val, (unsigned long)priv->reg_base + reg);
99}
100
101static u8 sja1000_isa_port_read_reg_indirect(const struct sja1000_priv *priv,
102					     int reg)
103{
104	unsigned long base = (unsigned long)priv->reg_base;
105
106	outb(reg, base);
107	return inb(base + 1);
108}
109
110static void sja1000_isa_port_write_reg_indirect(const struct sja1000_priv *priv,
111						int reg, u8 val)
112{
113	unsigned long base = (unsigned long)priv->reg_base;
114
115	outb(reg, base);
116	outb(val, base + 1);
117}
118
119static int sja1000_isa_probe(struct platform_device *pdev)
120{
121	struct net_device *dev;
122	struct sja1000_priv *priv;
123	void __iomem *base = NULL;
124	int iosize = SJA1000_IOSIZE;
125	int idx = pdev->id;
126	int err;
127
128	dev_dbg(&pdev->dev, "probing idx=%d: port=%#lx, mem=%#lx, irq=%d\n",
129		idx, port[idx], mem[idx], irq[idx]);
130
131	if (mem[idx]) {
132		if (!request_mem_region(mem[idx], iosize, DRV_NAME)) {
133			err = -EBUSY;
134			goto exit;
135		}
136		base = ioremap_nocache(mem[idx], iosize);
137		if (!base) {
138			err = -ENOMEM;
139			goto exit_release;
140		}
141	} else {
142		if (indirect[idx] > 0 ||
143		    (indirect[idx] == -1 && indirect[0] > 0))
144			iosize = SJA1000_IOSIZE_INDIRECT;
145		if (!request_region(port[idx], iosize, DRV_NAME)) {
146			err = -EBUSY;
147			goto exit;
148		}
149	}
150
151	dev = alloc_sja1000dev(0);
152	if (!dev) {
153		err = -ENOMEM;
154		goto exit_unmap;
155	}
156	priv = netdev_priv(dev);
157
158	dev->irq = irq[idx];
159	priv->irq_flags = IRQF_SHARED;
160	if (mem[idx]) {
161		priv->reg_base = base;
162		dev->base_addr = mem[idx];
163		priv->read_reg = sja1000_isa_mem_read_reg;
164		priv->write_reg = sja1000_isa_mem_write_reg;
165	} else {
166		priv->reg_base = (void __iomem *)port[idx];
167		dev->base_addr = port[idx];
168
169		if (iosize == SJA1000_IOSIZE_INDIRECT) {
170			priv->read_reg = sja1000_isa_port_read_reg_indirect;
171			priv->write_reg = sja1000_isa_port_write_reg_indirect;
172		} else {
173			priv->read_reg = sja1000_isa_port_read_reg;
174			priv->write_reg = sja1000_isa_port_write_reg;
175		}
176	}
177
178	if (clk[idx])
179		priv->can.clock.freq = clk[idx] / 2;
180	else if (clk[0])
181		priv->can.clock.freq = clk[0] / 2;
182	else
183		priv->can.clock.freq = CLK_DEFAULT / 2;
184
185	if (ocr[idx] != 0xff)
186		priv->ocr = ocr[idx];
187	else if (ocr[0] != 0xff)
188		priv->ocr = ocr[0];
189	else
190		priv->ocr = OCR_DEFAULT;
191
192	if (cdr[idx] != 0xff)
193		priv->cdr = cdr[idx];
194	else if (cdr[0] != 0xff)
195		priv->cdr = cdr[0];
196	else
197		priv->cdr = CDR_DEFAULT;
198
199	platform_set_drvdata(pdev, dev);
200	SET_NETDEV_DEV(dev, &pdev->dev);
201
202	err = register_sja1000dev(dev);
203	if (err) {
204		dev_err(&pdev->dev, "registering %s failed (err=%d)\n",
205			DRV_NAME, err);
206		goto exit_unmap;
207	}
208
209	dev_info(&pdev->dev, "%s device registered (reg_base=0x%p, irq=%d)\n",
210		 DRV_NAME, priv->reg_base, dev->irq);
211	return 0;
212
213 exit_unmap:
214	if (mem[idx])
215		iounmap(base);
216 exit_release:
217	if (mem[idx])
218		release_mem_region(mem[idx], iosize);
219	else
220		release_region(port[idx], iosize);
221 exit:
222	return err;
223}
224
225static int sja1000_isa_remove(struct platform_device *pdev)
226{
227	struct net_device *dev = platform_get_drvdata(pdev);
228	struct sja1000_priv *priv = netdev_priv(dev);
229	int idx = pdev->id;
230
231	unregister_sja1000dev(dev);
232
233	if (mem[idx]) {
234		iounmap(priv->reg_base);
235		release_mem_region(mem[idx], SJA1000_IOSIZE);
236	} else {
237		if (priv->read_reg == sja1000_isa_port_read_reg_indirect)
238			release_region(port[idx], SJA1000_IOSIZE_INDIRECT);
239		else
240			release_region(port[idx], SJA1000_IOSIZE);
241	}
242	free_sja1000dev(dev);
243
244	return 0;
245}
246
247static struct platform_driver sja1000_isa_driver = {
248	.probe = sja1000_isa_probe,
249	.remove = sja1000_isa_remove,
250	.driver = {
251		.name = DRV_NAME,
252		.owner = THIS_MODULE,
253	},
254};
255
256static int __init sja1000_isa_init(void)
257{
258	int idx, err;
259
260	for (idx = 0; idx < MAXDEV; idx++) {
261		if ((port[idx] || mem[idx]) && irq[idx]) {
262			sja1000_isa_devs[idx] =
263				platform_device_alloc(DRV_NAME, idx);
264			if (!sja1000_isa_devs[idx]) {
265				err = -ENOMEM;
266				goto exit_free_devices;
267			}
268			err = platform_device_add(sja1000_isa_devs[idx]);
269			if (err) {
270				platform_device_put(sja1000_isa_devs[idx]);
271				goto exit_free_devices;
272			}
273			pr_debug("%s: platform device %d: port=%#lx, mem=%#lx, "
274				 "irq=%d\n",
275				 DRV_NAME, idx, port[idx], mem[idx], irq[idx]);
276		} else if (idx == 0 || port[idx] || mem[idx]) {
277				pr_err("%s: insufficient parameters supplied\n",
278				       DRV_NAME);
279				err = -EINVAL;
280				goto exit_free_devices;
281		}
282	}
283
284	err = platform_driver_register(&sja1000_isa_driver);
285	if (err)
286		goto exit_free_devices;
287
288	pr_info("Legacy %s driver for max. %d devices registered\n",
289		DRV_NAME, MAXDEV);
290
291	return 0;
292
293exit_free_devices:
294	while (--idx >= 0) {
295		if (sja1000_isa_devs[idx])
296			platform_device_unregister(sja1000_isa_devs[idx]);
297	}
298
299	return err;
300}
301
302static void __exit sja1000_isa_exit(void)
303{
304	int idx;
305
306	platform_driver_unregister(&sja1000_isa_driver);
307	for (idx = 0; idx < MAXDEV; idx++) {
308		if (sja1000_isa_devs[idx])
309			platform_device_unregister(sja1000_isa_devs[idx]);
310	}
311}
312
313module_init(sja1000_isa_init);
314module_exit(sja1000_isa_exit);
315