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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>
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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
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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
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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
223
224
225 pp->bitbang.master = spi_master_get(master);
226 pp->bitbang.chipselect = lm70_chipselect;
227 pp->bitbang.txrx_word[SPI_MODE_0] = lm70_txrx;
228 pp->bitbang.flags = SPI_3WIRE;
229
230
231
232
233 pp->port = p;
234 pd = parport_register_device(p, DRVNAME,
235 NULL, NULL, NULL,
236 PARPORT_FLAG_EXCL, pp);
237 if (!pd) {
238 status = -ENOMEM;
239 goto out_free_master;
240 }
241 pp->pd = pd;
242
243 status = parport_claim(pd);
244 if (status < 0)
245 goto out_parport_unreg;
246
247
248
249
250 status = spi_bitbang_start(&pp->bitbang);
251 if (status < 0) {
252 printk(KERN_WARNING
253 "%s: spi_bitbang_start failed with status %d\n",
254 DRVNAME, status);
255 goto out_off_and_release;
256 }
257
258
259
260
261
262
263
264 strcpy(pp->info.modalias, "lm70");
265 pp->info.max_speed_hz = 6 * 1000 * 1000;
266 pp->info.chip_select = 0;
267 pp->info.mode = SPI_3WIRE | SPI_MODE_0;
268
269
270 parport_write_data(pp->port, lm70_INIT);
271
272
273
274
275 pp->info.controller_data = pp;
276 pp->spidev_lm70 = spi_new_device(pp->bitbang.master, &pp->info);
277 if (pp->spidev_lm70)
278 dev_dbg(&pp->spidev_lm70->dev, "spidev_lm70 at %s\n",
279 dev_name(&pp->spidev_lm70->dev));
280 else {
281 printk(KERN_WARNING "%s: spi_new_device failed\n", DRVNAME);
282 status = -ENODEV;
283 goto out_bitbang_stop;
284 }
285 pp->spidev_lm70->bits_per_word = 8;
286
287 lm70llp = pp;
288 return;
289
290out_bitbang_stop:
291 spi_bitbang_stop(&pp->bitbang);
292out_off_and_release:
293
294 parport_write_data(pp->port, 0);
295 mdelay(10);
296 parport_release(pp->pd);
297out_parport_unreg:
298 parport_unregister_device(pd);
299out_free_master:
300 (void) spi_master_put(master);
301out_fail:
302 pr_info("%s: spi_lm70llp probe fail, status %d\n", DRVNAME, status);
303}
304
305static void spi_lm70llp_detach(struct parport *p)
306{
307 struct spi_lm70llp *pp;
308
309 if (!lm70llp || lm70llp->port != p)
310 return;
311
312 pp = lm70llp;
313 spi_bitbang_stop(&pp->bitbang);
314
315
316 parport_write_data(pp->port, 0);
317
318 parport_release(pp->pd);
319 parport_unregister_device(pp->pd);
320
321 (void) spi_master_put(pp->bitbang.master);
322
323 lm70llp = NULL;
324}
325
326
327static struct parport_driver spi_lm70llp_drv = {
328 .name = DRVNAME,
329 .attach = spi_lm70llp_attach,
330 .detach = spi_lm70llp_detach,
331};
332
333static int __init init_spi_lm70llp(void)
334{
335 return parport_register_driver(&spi_lm70llp_drv);
336}
337module_init(init_spi_lm70llp);
338
339static void __exit cleanup_spi_lm70llp(void)
340{
341 parport_unregister_driver(&spi_lm70llp_drv);
342}
343module_exit(cleanup_spi_lm70llp);
344
345MODULE_AUTHOR("Kaiwan N Billimoria <kaiwan@designergraphix.com>");
346MODULE_DESCRIPTION(
347 "Parport adapter for the National Semiconductor LM70 LLP eval board");
348MODULE_LICENSE("GPL");
349