1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Copyright (C) 2009 Wolfgang Grandegger <wg@grandegger.com>
4 */
5
6 #include <linux/kernel.h>
7 #include <linux/module.h>
8 #include <linux/platform_device.h>
9 #include <linux/interrupt.h>
10 #include <linux/netdevice.h>
11 #include <linux/delay.h>
12 #include <linux/irq.h>
13 #include <linux/io.h>
14 #include <linux/can/dev.h>
15 #include <linux/can/platform/sja1000.h>
16
17 #include "sja1000.h"
18
19 #define DRV_NAME "sja1000_isa"
20
21 #define MAXDEV 8
22
23 MODULE_AUTHOR("Wolfgang Grandegger <wg@grandegger.com>");
24 MODULE_DESCRIPTION("Socket-CAN driver for SJA1000 on the ISA bus");
25 MODULE_LICENSE("GPL v2");
26
27 #define CLK_DEFAULT 16000000 /* 16 MHz */
28 #define CDR_DEFAULT (CDR_CBP | CDR_CLK_OFF)
29 #define OCR_DEFAULT OCR_TX0_PUSHPULL
30
31 static unsigned long port[MAXDEV];
32 static unsigned long mem[MAXDEV];
33 static int irq[MAXDEV];
34 static int clk[MAXDEV];
35 static unsigned char cdr[MAXDEV] = {[0 ... (MAXDEV - 1)] = 0xff};
36 static unsigned char ocr[MAXDEV] = {[0 ... (MAXDEV - 1)] = 0xff};
37 static int indirect[MAXDEV] = {[0 ... (MAXDEV - 1)] = -1};
38 static spinlock_t indirect_lock[MAXDEV]; /* lock for indirect access mode */
39
40 module_param_hw_array(port, ulong, ioport, NULL, 0444);
41 MODULE_PARM_DESC(port, "I/O port number");
42
43 module_param_hw_array(mem, ulong, iomem, NULL, 0444);
44 MODULE_PARM_DESC(mem, "I/O memory address");
45
46 module_param_hw_array(indirect, int, ioport, NULL, 0444);
47 MODULE_PARM_DESC(indirect, "Indirect access via address and data port");
48
49 module_param_hw_array(irq, int, irq, NULL, 0444);
50 MODULE_PARM_DESC(irq, "IRQ number");
51
52 module_param_array(clk, int, NULL, 0444);
53 MODULE_PARM_DESC(clk, "External oscillator clock frequency "
54 "(default=16000000 [16 MHz])");
55
56 module_param_array(cdr, byte, NULL, 0444);
57 MODULE_PARM_DESC(cdr, "Clock divider register "
58 "(default=0x48 [CDR_CBP | CDR_CLK_OFF])");
59
60 module_param_array(ocr, byte, NULL, 0444);
61 MODULE_PARM_DESC(ocr, "Output control register "
62 "(default=0x18 [OCR_TX0_PUSHPULL])");
63
64 #define SJA1000_IOSIZE 0x20
65 #define SJA1000_IOSIZE_INDIRECT 0x02
66
67 static struct platform_device *sja1000_isa_devs[MAXDEV];
68
sja1000_isa_mem_read_reg(const struct sja1000_priv * priv,int reg)69 static u8 sja1000_isa_mem_read_reg(const struct sja1000_priv *priv, int reg)
70 {
71 return readb(priv->reg_base + reg);
72 }
73
sja1000_isa_mem_write_reg(const struct sja1000_priv * priv,int reg,u8 val)74 static void sja1000_isa_mem_write_reg(const struct sja1000_priv *priv,
75 int reg, u8 val)
76 {
77 writeb(val, priv->reg_base + reg);
78 }
79
sja1000_isa_port_read_reg(const struct sja1000_priv * priv,int reg)80 static u8 sja1000_isa_port_read_reg(const struct sja1000_priv *priv, int reg)
81 {
82 return inb((unsigned long)priv->reg_base + reg);
83 }
84
sja1000_isa_port_write_reg(const struct sja1000_priv * priv,int reg,u8 val)85 static void sja1000_isa_port_write_reg(const struct sja1000_priv *priv,
86 int reg, u8 val)
87 {
88 outb(val, (unsigned long)priv->reg_base + reg);
89 }
90
sja1000_isa_port_read_reg_indirect(const struct sja1000_priv * priv,int reg)91 static u8 sja1000_isa_port_read_reg_indirect(const struct sja1000_priv *priv,
92 int reg)
93 {
94 unsigned long flags, base = (unsigned long)priv->reg_base;
95 u8 readval;
96
97 spin_lock_irqsave(&indirect_lock[priv->dev->dev_id], flags);
98 outb(reg, base);
99 readval = inb(base + 1);
100 spin_unlock_irqrestore(&indirect_lock[priv->dev->dev_id], flags);
101
102 return readval;
103 }
104
sja1000_isa_port_write_reg_indirect(const struct sja1000_priv * priv,int reg,u8 val)105 static void sja1000_isa_port_write_reg_indirect(const struct sja1000_priv *priv,
106 int reg, u8 val)
107 {
108 unsigned long flags, base = (unsigned long)priv->reg_base;
109
110 spin_lock_irqsave(&indirect_lock[priv->dev->dev_id], flags);
111 outb(reg, base);
112 outb(val, base + 1);
113 spin_unlock_irqrestore(&indirect_lock[priv->dev->dev_id], flags);
114 }
115
sja1000_isa_probe(struct platform_device * pdev)116 static int sja1000_isa_probe(struct platform_device *pdev)
117 {
118 struct net_device *dev;
119 struct sja1000_priv *priv;
120 void __iomem *base = NULL;
121 int iosize = SJA1000_IOSIZE;
122 int idx = pdev->id;
123 int err;
124
125 dev_dbg(&pdev->dev, "probing idx=%d: port=%#lx, mem=%#lx, irq=%d\n",
126 idx, port[idx], mem[idx], irq[idx]);
127
128 if (mem[idx]) {
129 if (!request_mem_region(mem[idx], iosize, DRV_NAME)) {
130 err = -EBUSY;
131 goto exit;
132 }
133 base = ioremap(mem[idx], iosize);
134 if (!base) {
135 err = -ENOMEM;
136 goto exit_release;
137 }
138 } else {
139 if (indirect[idx] > 0 ||
140 (indirect[idx] == -1 && indirect[0] > 0))
141 iosize = SJA1000_IOSIZE_INDIRECT;
142 if (!request_region(port[idx], iosize, DRV_NAME)) {
143 err = -EBUSY;
144 goto exit;
145 }
146 }
147
148 dev = alloc_sja1000dev(0);
149 if (!dev) {
150 err = -ENOMEM;
151 goto exit_unmap;
152 }
153 priv = netdev_priv(dev);
154
155 dev->irq = irq[idx];
156 priv->irq_flags = IRQF_SHARED;
157 if (mem[idx]) {
158 priv->reg_base = base;
159 dev->base_addr = mem[idx];
160 priv->read_reg = sja1000_isa_mem_read_reg;
161 priv->write_reg = sja1000_isa_mem_write_reg;
162 } else {
163 priv->reg_base = (void __iomem *)port[idx];
164 dev->base_addr = port[idx];
165
166 if (iosize == SJA1000_IOSIZE_INDIRECT) {
167 priv->read_reg = sja1000_isa_port_read_reg_indirect;
168 priv->write_reg = sja1000_isa_port_write_reg_indirect;
169 spin_lock_init(&indirect_lock[idx]);
170 } else {
171 priv->read_reg = sja1000_isa_port_read_reg;
172 priv->write_reg = sja1000_isa_port_write_reg;
173 }
174 }
175
176 if (clk[idx])
177 priv->can.clock.freq = clk[idx] / 2;
178 else if (clk[0])
179 priv->can.clock.freq = clk[0] / 2;
180 else
181 priv->can.clock.freq = CLK_DEFAULT / 2;
182
183 if (ocr[idx] != 0xff)
184 priv->ocr = ocr[idx];
185 else if (ocr[0] != 0xff)
186 priv->ocr = ocr[0];
187 else
188 priv->ocr = OCR_DEFAULT;
189
190 if (cdr[idx] != 0xff)
191 priv->cdr = cdr[idx];
192 else if (cdr[0] != 0xff)
193 priv->cdr = cdr[0];
194 else
195 priv->cdr = CDR_DEFAULT;
196
197 platform_set_drvdata(pdev, dev);
198 SET_NETDEV_DEV(dev, &pdev->dev);
199 dev->dev_id = idx;
200
201 err = register_sja1000dev(dev);
202 if (err) {
203 dev_err(&pdev->dev, "registering %s failed (err=%d)\n",
204 DRV_NAME, err);
205 goto exit_free;
206 }
207
208 dev_info(&pdev->dev, "%s device registered (reg_base=0x%p, irq=%d)\n",
209 DRV_NAME, priv->reg_base, dev->irq);
210 return 0;
211
212 exit_free:
213 free_sja1000dev(dev);
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
sja1000_isa_remove(struct platform_device * pdev)226 static void 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
246 static struct platform_driver sja1000_isa_driver = {
247 .probe = sja1000_isa_probe,
248 .remove = sja1000_isa_remove,
249 .driver = {
250 .name = DRV_NAME,
251 },
252 };
253
sja1000_isa_init(void)254 static int __init sja1000_isa_init(void)
255 {
256 int idx, err;
257
258 for (idx = 0; idx < MAXDEV; idx++) {
259 if ((port[idx] || mem[idx]) && irq[idx]) {
260 sja1000_isa_devs[idx] =
261 platform_device_alloc(DRV_NAME, idx);
262 if (!sja1000_isa_devs[idx]) {
263 err = -ENOMEM;
264 goto exit_free_devices;
265 }
266 err = platform_device_add(sja1000_isa_devs[idx]);
267 if (err) {
268 platform_device_put(sja1000_isa_devs[idx]);
269 goto exit_free_devices;
270 }
271 pr_debug("%s: platform device %d: port=%#lx, mem=%#lx, "
272 "irq=%d\n",
273 DRV_NAME, idx, port[idx], mem[idx], irq[idx]);
274 } else if (idx == 0 || port[idx] || mem[idx]) {
275 pr_err("%s: insufficient parameters supplied\n",
276 DRV_NAME);
277 err = -EINVAL;
278 goto exit_free_devices;
279 }
280 }
281
282 err = platform_driver_register(&sja1000_isa_driver);
283 if (err)
284 goto exit_free_devices;
285
286 pr_info("Legacy %s driver for max. %d devices registered\n",
287 DRV_NAME, MAXDEV);
288
289 return 0;
290
291 exit_free_devices:
292 while (--idx >= 0) {
293 if (sja1000_isa_devs[idx])
294 platform_device_unregister(sja1000_isa_devs[idx]);
295 }
296
297 return err;
298 }
299
sja1000_isa_exit(void)300 static void __exit sja1000_isa_exit(void)
301 {
302 int idx;
303
304 platform_driver_unregister(&sja1000_isa_driver);
305 for (idx = 0; idx < MAXDEV; idx++) {
306 if (sja1000_isa_devs[idx])
307 platform_device_unregister(sja1000_isa_devs[idx]);
308 }
309 }
310
311 module_init(sja1000_isa_init);
312 module_exit(sja1000_isa_exit);
313