sja1000_isa.c revision a9edcdedbd3d8f3ffcd7bdcab5812707a25e554e 
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};
49static spinlock_t indirect_lock[MAXDEV];  /* lock for indirect access mode */
50
51module_param_array(port, ulong, NULL, S_IRUGO);
52MODULE_PARM_DESC(port, "I/O port number");
53
54module_param_array(mem, ulong, NULL, S_IRUGO);
55MODULE_PARM_DESC(mem, "I/O memory address");
56
57module_param_array(indirect, int, NULL, S_IRUGO);
58MODULE_PARM_DESC(indirect, "Indirect access via address and data port");
59
60module_param_array(irq, int, NULL, S_IRUGO);
61MODULE_PARM_DESC(irq, "IRQ number");
62
63module_param_array(clk, int, NULL, S_IRUGO);
64MODULE_PARM_DESC(clk, "External oscillator clock frequency "
65		 "(default=16000000 [16 MHz])");
66
67module_param_array(cdr, byte, NULL, S_IRUGO);
68MODULE_PARM_DESC(cdr, "Clock divider register "
69		 "(default=0x48 [CDR_CBP | CDR_CLK_OFF])");
70
71module_param_array(ocr, byte, NULL, S_IRUGO);
72MODULE_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
78static struct platform_device *sja1000_isa_devs[MAXDEV];
79
80static u8 sja1000_isa_mem_read_reg(const struct sja1000_priv *priv, int reg)
81{
82	return readb(priv->reg_base + reg);
83}
84
85static 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
91static 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
96static 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
102static 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
116static 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
127static 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_unmap;
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_unmap:
224	if (mem[idx])
225		iounmap(base);
226 exit_release:
227	if (mem[idx])
228		release_mem_region(mem[idx], iosize);
229	else
230		release_region(port[idx], iosize);
231 exit:
232	return err;
233}
234
235static int sja1000_isa_remove(struct platform_device *pdev)
236{
237	struct net_device *dev = platform_get_drvdata(pdev);
238	struct sja1000_priv *priv = netdev_priv(dev);
239	int idx = pdev->id;
240
241	unregister_sja1000dev(dev);
242
243	if (mem[idx]) {
244		iounmap(priv->reg_base);
245		release_mem_region(mem[idx], SJA1000_IOSIZE);
246	} else {
247		if (priv->read_reg == sja1000_isa_port_read_reg_indirect)
248			release_region(port[idx], SJA1000_IOSIZE_INDIRECT);
249		else
250			release_region(port[idx], SJA1000_IOSIZE);
251	}
252	free_sja1000dev(dev);
253
254	return 0;
255}
256
257static struct platform_driver sja1000_isa_driver = {
258	.probe = sja1000_isa_probe,
259	.remove = sja1000_isa_remove,
260	.driver = {
261		.name = DRV_NAME,
262		.owner = THIS_MODULE,
263	},
264};
265
266static int __init sja1000_isa_init(void)
267{
268	int idx, err;
269
270	for (idx = 0; idx < MAXDEV; idx++) {
271		if ((port[idx] || mem[idx]) && irq[idx]) {
272			sja1000_isa_devs[idx] =
273				platform_device_alloc(DRV_NAME, idx);
274			if (!sja1000_isa_devs[idx]) {
275				err = -ENOMEM;
276				goto exit_free_devices;
277			}
278			err = platform_device_add(sja1000_isa_devs[idx]);
279			if (err) {
280				platform_device_put(sja1000_isa_devs[idx]);
281				goto exit_free_devices;
282			}
283			pr_debug("%s: platform device %d: port=%#lx, mem=%#lx, "
284				 "irq=%d\n",
285				 DRV_NAME, idx, port[idx], mem[idx], irq[idx]);
286		} else if (idx == 0 || port[idx] || mem[idx]) {
287				pr_err("%s: insufficient parameters supplied\n",
288				       DRV_NAME);
289				err = -EINVAL;
290				goto exit_free_devices;
291		}
292	}
293
294	err = platform_driver_register(&sja1000_isa_driver);
295	if (err)
296		goto exit_free_devices;
297
298	pr_info("Legacy %s driver for max. %d devices registered\n",
299		DRV_NAME, MAXDEV);
300
301	return 0;
302
303exit_free_devices:
304	while (--idx >= 0) {
305		if (sja1000_isa_devs[idx])
306			platform_device_unregister(sja1000_isa_devs[idx]);
307	}
308
309	return err;
310}
311
312static void __exit sja1000_isa_exit(void)
313{
314	int idx;
315
316	platform_driver_unregister(&sja1000_isa_driver);
317	for (idx = 0; idx < MAXDEV; idx++) {
318		if (sja1000_isa_devs[idx])
319			platform_device_unregister(sja1000_isa_devs[idx]);
320	}
321}
322
323module_init(sja1000_isa_init);
324module_exit(sja1000_isa_exit);
325