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, write to the Free Software
15  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
16  */
17 
18 #include <linux/kernel.h>
19 #include <linux/module.h>
20 #include <linux/platform_device.h>
21 #include <linux/interrupt.h>
22 #include <linux/netdevice.h>
23 #include <linux/delay.h>
24 #include <linux/irq.h>
25 #include <linux/io.h>
26 #include <linux/can/dev.h>
27 #include <linux/can/platform/sja1000.h>
28 
29 #include "sja1000.h"
30 
31 #define DRV_NAME "sja1000_isa"
32 
33 #define MAXDEV 8
34 
35 MODULE_AUTHOR("Wolfgang Grandegger <wg@grandegger.com>");
36 MODULE_DESCRIPTION("Socket-CAN driver for SJA1000 on the ISA bus");
37 MODULE_LICENSE("GPL v2");
38 
39 #define CLK_DEFAULT	16000000	/* 16 MHz */
40 #define CDR_DEFAULT	(CDR_CBP | CDR_CLK_OFF)
41 #define OCR_DEFAULT	OCR_TX0_PUSHPULL
42 
43 static unsigned long port[MAXDEV];
44 static unsigned long mem[MAXDEV];
45 static int irq[MAXDEV];
46 static int clk[MAXDEV];
47 static unsigned char cdr[MAXDEV] = {[0 ... (MAXDEV - 1)] = 0xff};
48 static unsigned char ocr[MAXDEV] = {[0 ... (MAXDEV - 1)] = 0xff};
49 static int indirect[MAXDEV] = {[0 ... (MAXDEV - 1)] = -1};
50 
51 module_param_array(port, ulong, NULL, S_IRUGO);
52 MODULE_PARM_DESC(port, "I/O port number");
53 
54 module_param_array(mem, ulong, NULL, S_IRUGO);
55 MODULE_PARM_DESC(mem, "I/O memory address");
56 
57 module_param_array(indirect, int, NULL, S_IRUGO);
58 MODULE_PARM_DESC(indirect, "Indirect access via address and data port");
59 
60 module_param_array(irq, int, NULL, S_IRUGO);
61 MODULE_PARM_DESC(irq, "IRQ number");
62 
63 module_param_array(clk, int, NULL, S_IRUGO);
64 MODULE_PARM_DESC(clk, "External oscillator clock frequency "
65 		 "(default=16000000 [16 MHz])");
66 
67 module_param_array(cdr, byte, NULL, S_IRUGO);
68 MODULE_PARM_DESC(cdr, "Clock divider register "
69 		 "(default=0x48 [CDR_CBP | CDR_CLK_OFF])");
70 
71 module_param_array(ocr, byte, NULL, S_IRUGO);
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 base = (unsigned long)priv->reg_base;
106 
107 	outb(reg, base);
108 	return inb(base + 1);
109 }
110 
111 static void sja1000_isa_port_write_reg_indirect(const struct sja1000_priv *priv,
112 						int reg, u8 val)
113 {
114 	unsigned long base = (unsigned long)priv->reg_base;
115 
116 	outb(reg, base);
117 	outb(val, base + 1);
118 }
119 
120 static int sja1000_isa_probe(struct platform_device *pdev)
121 {
122 	struct net_device *dev;
123 	struct sja1000_priv *priv;
124 	void __iomem *base = NULL;
125 	int iosize = SJA1000_IOSIZE;
126 	int idx = pdev->id;
127 	int err;
128 
129 	dev_dbg(&pdev->dev, "probing idx=%d: port=%#lx, mem=%#lx, irq=%d\n",
130 		idx, port[idx], mem[idx], irq[idx]);
131 
132 	if (mem[idx]) {
133 		if (!request_mem_region(mem[idx], iosize, DRV_NAME)) {
134 			err = -EBUSY;
135 			goto exit;
136 		}
137 		base = ioremap_nocache(mem[idx], iosize);
138 		if (!base) {
139 			err = -ENOMEM;
140 			goto exit_release;
141 		}
142 	} else {
143 		if (indirect[idx] > 0 ||
144 		    (indirect[idx] == -1 && indirect[0] > 0))
145 			iosize = SJA1000_IOSIZE_INDIRECT;
146 		if (!request_region(port[idx], iosize, DRV_NAME)) {
147 			err = -EBUSY;
148 			goto exit;
149 		}
150 	}
151 
152 	dev = alloc_sja1000dev(0);
153 	if (!dev) {
154 		err = -ENOMEM;
155 		goto exit_unmap;
156 	}
157 	priv = netdev_priv(dev);
158 
159 	dev->irq = irq[idx];
160 	priv->irq_flags = IRQF_SHARED;
161 	if (mem[idx]) {
162 		priv->reg_base = base;
163 		dev->base_addr = mem[idx];
164 		priv->read_reg = sja1000_isa_mem_read_reg;
165 		priv->write_reg = sja1000_isa_mem_write_reg;
166 	} else {
167 		priv->reg_base = (void __iomem *)port[idx];
168 		dev->base_addr = port[idx];
169 
170 		if (iosize == SJA1000_IOSIZE_INDIRECT) {
171 			priv->read_reg = sja1000_isa_port_read_reg_indirect;
172 			priv->write_reg = sja1000_isa_port_write_reg_indirect;
173 		} else {
174 			priv->read_reg = sja1000_isa_port_read_reg;
175 			priv->write_reg = sja1000_isa_port_write_reg;
176 		}
177 	}
178 
179 	if (clk[idx])
180 		priv->can.clock.freq = clk[idx] / 2;
181 	else if (clk[0])
182 		priv->can.clock.freq = clk[0] / 2;
183 	else
184 		priv->can.clock.freq = CLK_DEFAULT / 2;
185 
186 	if (ocr[idx] != 0xff)
187 		priv->ocr = ocr[idx];
188 	else if (ocr[0] != 0xff)
189 		priv->ocr = ocr[0];
190 	else
191 		priv->ocr = OCR_DEFAULT;
192 
193 	if (cdr[idx] != 0xff)
194 		priv->cdr = cdr[idx];
195 	else if (cdr[0] != 0xff)
196 		priv->cdr = cdr[0];
197 	else
198 		priv->cdr = CDR_DEFAULT;
199 
200 	platform_set_drvdata(pdev, dev);
201 	SET_NETDEV_DEV(dev, &pdev->dev);
202 
203 	err = register_sja1000dev(dev);
204 	if (err) {
205 		dev_err(&pdev->dev, "registering %s failed (err=%d)\n",
206 			DRV_NAME, err);
207 		goto exit_unmap;
208 	}
209 
210 	dev_info(&pdev->dev, "%s device registered (reg_base=0x%p, irq=%d)\n",
211 		 DRV_NAME, priv->reg_base, dev->irq);
212 	return 0;
213 
214  exit_unmap:
215 	if (mem[idx])
216 		iounmap(base);
217  exit_release:
218 	if (mem[idx])
219 		release_mem_region(mem[idx], iosize);
220 	else
221 		release_region(port[idx], iosize);
222  exit:
223 	return err;
224 }
225 
226 static int sja1000_isa_remove(struct platform_device *pdev)
227 {
228 	struct net_device *dev = platform_get_drvdata(pdev);
229 	struct sja1000_priv *priv = netdev_priv(dev);
230 	int idx = pdev->id;
231 
232 	unregister_sja1000dev(dev);
233 
234 	if (mem[idx]) {
235 		iounmap(priv->reg_base);
236 		release_mem_region(mem[idx], SJA1000_IOSIZE);
237 	} else {
238 		if (priv->read_reg == sja1000_isa_port_read_reg_indirect)
239 			release_region(port[idx], SJA1000_IOSIZE_INDIRECT);
240 		else
241 			release_region(port[idx], SJA1000_IOSIZE);
242 	}
243 	free_sja1000dev(dev);
244 
245 	return 0;
246 }
247 
248 static struct platform_driver sja1000_isa_driver = {
249 	.probe = sja1000_isa_probe,
250 	.remove = sja1000_isa_remove,
251 	.driver = {
252 		.name = DRV_NAME,
253 		.owner = THIS_MODULE,
254 	},
255 };
256 
257 static int __init sja1000_isa_init(void)
258 {
259 	int idx, err;
260 
261 	for (idx = 0; idx < MAXDEV; idx++) {
262 		if ((port[idx] || mem[idx]) && irq[idx]) {
263 			sja1000_isa_devs[idx] =
264 				platform_device_alloc(DRV_NAME, idx);
265 			if (!sja1000_isa_devs[idx]) {
266 				err = -ENOMEM;
267 				goto exit_free_devices;
268 			}
269 			err = platform_device_add(sja1000_isa_devs[idx]);
270 			if (err) {
271 				platform_device_put(sja1000_isa_devs[idx]);
272 				goto exit_free_devices;
273 			}
274 			pr_debug("%s: platform device %d: port=%#lx, mem=%#lx, "
275 				 "irq=%d\n",
276 				 DRV_NAME, idx, port[idx], mem[idx], irq[idx]);
277 		} else if (idx == 0 || port[idx] || mem[idx]) {
278 				pr_err("%s: insufficient parameters supplied\n",
279 				       DRV_NAME);
280 				err = -EINVAL;
281 				goto exit_free_devices;
282 		}
283 	}
284 
285 	err = platform_driver_register(&sja1000_isa_driver);
286 	if (err)
287 		goto exit_free_devices;
288 
289 	pr_info("Legacy %s driver for max. %d devices registered\n",
290 		DRV_NAME, MAXDEV);
291 
292 	return 0;
293 
294 exit_free_devices:
295 	while (--idx >= 0) {
296 		if (sja1000_isa_devs[idx])
297 			platform_device_unregister(sja1000_isa_devs[idx]);
298 	}
299 
300 	return err;
301 }
302 
303 static void __exit sja1000_isa_exit(void)
304 {
305 	int idx;
306 
307 	platform_driver_unregister(&sja1000_isa_driver);
308 	for (idx = 0; idx < MAXDEV; idx++) {
309 		if (sja1000_isa_devs[idx])
310 			platform_device_unregister(sja1000_isa_devs[idx]);
311 	}
312 }
313 
314 module_init(sja1000_isa_init);
315 module_exit(sja1000_isa_exit);
316