1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21#include <linux/init.h>
22#include <linux/module.h>
23#include <linux/kernel.h>
24#include <linux/delay.h>
25#include <linux/device.h>
26#include <linux/parport.h>
27#include <linux/sysfs.h>
28#include <linux/workqueue.h>
29
30
31#include <linux/spi/spi.h>
32#include <linux/spi/spi_bitbang.h>
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74#define DRVNAME "spi-lm70llp"
75
76#define lm70_INIT 0xBE
77#define SIO 0x10
78#define nCS 0x20
79#define SCLK 0x40
80
81
82
83struct spi_lm70llp {
84 struct spi_bitbang bitbang;
85 struct parport *port;
86 struct pardevice *pd;
87 struct spi_device *spidev_lm70;
88 struct spi_board_info info;
89
90};
91
92
93static struct spi_lm70llp *lm70llp;
94
95
96
97
98static inline struct spi_lm70llp *spidev_to_pp(struct spi_device *spi)
99{
100 return spi->controller_data;
101}
102
103
104
105
106
107
108
109
110static inline void deassertCS(struct spi_lm70llp *pp)
111{
112 u8 data = parport_read_data(pp->port);
113
114 data &= ~0x80;
115 parport_write_data(pp->port, data | nCS);
116}
117
118static inline void assertCS(struct spi_lm70llp *pp)
119{
120 u8 data = parport_read_data(pp->port);
121
122 data |= 0x80;
123 parport_write_data(pp->port, data & ~nCS);
124}
125
126static inline void clkHigh(struct spi_lm70llp *pp)
127{
128 u8 data = parport_read_data(pp->port);
129 parport_write_data(pp->port, data | SCLK);
130}
131
132static inline void clkLow(struct spi_lm70llp *pp)
133{
134 u8 data = parport_read_data(pp->port);
135 parport_write_data(pp->port, data & ~SCLK);
136}
137
138
139
140static inline void spidelay(unsigned d)
141{
142 udelay(d);
143}
144
145static inline void setsck(struct spi_device *s, int is_on)
146{
147 struct spi_lm70llp *pp = spidev_to_pp(s);
148
149 if (is_on)
150 clkHigh(pp);
151 else
152 clkLow(pp);
153}
154
155static inline void setmosi(struct spi_device *s, int is_on)
156{
157
158
159
160
161}
162
163
164
165
166
167
168
169
170static inline int getmiso(struct spi_device *s)
171{
172 struct spi_lm70llp *pp = spidev_to_pp(s);
173 return ((SIO == (parport_read_status(pp->port) & SIO)) ? 0 : 1 );
174}
175
176
177#include "spi_bitbang_txrx.h"
178
179static void lm70_chipselect(struct spi_device *spi, int value)
180{
181 struct spi_lm70llp *pp = spidev_to_pp(spi);
182
183 if (value)
184 assertCS(pp);
185 else
186 deassertCS(pp);
187}
188
189
190
191
192static u32 lm70_txrx(struct spi_device *spi, unsigned nsecs, u32 word, u8 bits)
193{
194 return bitbang_txrx_be_cpha0(spi, nsecs, 0, 0, word, bits);
195}
196
197static void spi_lm70llp_attach(struct parport *p)
198{
199 struct pardevice *pd;
200 struct spi_lm70llp *pp;
201 struct spi_master *master;
202 int status;
203
204 if (lm70llp) {
205 printk(KERN_WARNING
206 "%s: spi_lm70llp instance already loaded. Aborting.\n",
207 DRVNAME);
208 return;
209 }
210
211
212
213
214
215 master = spi_alloc_master(p->physport->dev, sizeof *pp);
216 if (!master) {
217 status = -ENOMEM;
218 goto out_fail;
219 }
220 pp = spi_master_get_devdata(master);
221
222 master->bus_num = -1;
223 master->num_chipselect = 1;
224
225
226
227
228 pp->bitbang.master = spi_master_get(master);
229 pp->bitbang.chipselect = lm70_chipselect;
230 pp->bitbang.txrx_word[SPI_MODE_0] = lm70_txrx;
231 pp->bitbang.flags = SPI_3WIRE;
232
233
234
235
236 pp->port = p;
237 pd = parport_register_device(p, DRVNAME,
238 NULL, NULL, NULL,
239 PARPORT_FLAG_EXCL, pp);
240 if (!pd) {
241 status = -ENOMEM;
242 goto out_free_master;
243 }
244 pp->pd = pd;
245
246 status = parport_claim(pd);
247 if (status < 0)
248 goto out_parport_unreg;
249
250
251
252
253 status = spi_bitbang_start(&pp->bitbang);
254 if (status < 0) {
255 printk(KERN_WARNING
256 "%s: spi_bitbang_start failed with status %d\n",
257 DRVNAME, status);
258 goto out_off_and_release;
259 }
260
261
262
263
264
265
266
267 strcpy(pp->info.modalias, "lm70");
268 pp->info.max_speed_hz = 6 * 1000 * 1000;
269 pp->info.chip_select = 0;
270 pp->info.mode = SPI_3WIRE | SPI_MODE_0;
271
272
273 parport_write_data(pp->port, lm70_INIT);
274
275
276
277
278 pp->info.controller_data = pp;
279 pp->spidev_lm70 = spi_new_device(pp->bitbang.master, &pp->info);
280 if (pp->spidev_lm70)
281 dev_dbg(&pp->spidev_lm70->dev, "spidev_lm70 at %s\n",
282 dev_name(&pp->spidev_lm70->dev));
283 else {
284 printk(KERN_WARNING "%s: spi_new_device failed\n", DRVNAME);
285 status = -ENODEV;
286 goto out_bitbang_stop;
287 }
288 pp->spidev_lm70->bits_per_word = 8;
289
290 lm70llp = pp;
291 return;
292
293out_bitbang_stop:
294 spi_bitbang_stop(&pp->bitbang);
295out_off_and_release:
296
297 parport_write_data(pp->port, 0);
298 mdelay(10);
299 parport_release(pp->pd);
300out_parport_unreg:
301 parport_unregister_device(pd);
302out_free_master:
303 (void) spi_master_put(master);
304out_fail:
305 pr_info("%s: spi_lm70llp probe fail, status %d\n", DRVNAME, status);
306}
307
308static void spi_lm70llp_detach(struct parport *p)
309{
310 struct spi_lm70llp *pp;
311
312 if (!lm70llp || lm70llp->port != p)
313 return;
314
315 pp = lm70llp;
316 spi_bitbang_stop(&pp->bitbang);
317
318
319 parport_write_data(pp->port, 0);
320
321 parport_release(pp->pd);
322 parport_unregister_device(pp->pd);
323
324 (void) spi_master_put(pp->bitbang.master);
325
326 lm70llp = NULL;
327}
328
329
330static struct parport_driver spi_lm70llp_drv = {
331 .name = DRVNAME,
332 .attach = spi_lm70llp_attach,
333 .detach = spi_lm70llp_detach,
334};
335
336static int __init init_spi_lm70llp(void)
337{
338 return parport_register_driver(&spi_lm70llp_drv);
339}
340module_init(init_spi_lm70llp);
341
342static void __exit cleanup_spi_lm70llp(void)
343{
344 parport_unregister_driver(&spi_lm70llp_drv);
345}
346module_exit(cleanup_spi_lm70llp);
347
348MODULE_AUTHOR("Kaiwan N Billimoria <kaiwan@designergraphix.com>");
349MODULE_DESCRIPTION(
350 "Parport adapter for the National Semiconductor LM70 LLP eval board");
351MODULE_LICENSE("GPL");
352