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20#include <linux/kernel.h>
21#include <linux/init.h>
22#include <linux/delay.h>
23#include <linux/device.h>
24#include <linux/parport.h>
25
26#include <linux/sched.h>
27#include <linux/spi/spi.h>
28#include <linux/spi/spi_bitbang.h>
29#include <linux/spi/flash.h>
30
31#include <linux/mtd/partitions.h>
32
33
34
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36
37
38
39
40
41
42
43
44
45#define butterfly_nreset (1 << 1)
46
47#define spi_sck_bit (1 << 0)
48#define spi_mosi_bit (1 << 7)
49
50#define vcc_bits ((1 << 6) | (1 << 5))
51
52
53#define spi_miso_bit PARPORT_STATUS_BUSY
54
55
56#define spi_cs_bit PARPORT_CONTROL_SELECT
57
58
59
60static inline struct butterfly *spidev_to_pp(struct spi_device *spi)
61{
62 return spi->controller_data;
63}
64
65
66struct butterfly {
67
68 struct spi_bitbang bitbang;
69
70 struct parport *port;
71 struct pardevice *pd;
72
73 u8 lastbyte;
74
75 struct spi_device *dataflash;
76 struct spi_device *butterfly;
77 struct spi_board_info info[2];
78
79};
80
81
82
83static inline void
84setsck(struct spi_device *spi, int is_on)
85{
86 struct butterfly *pp = spidev_to_pp(spi);
87 u8 bit, byte = pp->lastbyte;
88
89 bit = spi_sck_bit;
90
91 if (is_on)
92 byte |= bit;
93 else
94 byte &= ~bit;
95 parport_write_data(pp->port, byte);
96 pp->lastbyte = byte;
97}
98
99static inline void
100setmosi(struct spi_device *spi, int is_on)
101{
102 struct butterfly *pp = spidev_to_pp(spi);
103 u8 bit, byte = pp->lastbyte;
104
105 bit = spi_mosi_bit;
106
107 if (is_on)
108 byte |= bit;
109 else
110 byte &= ~bit;
111 parport_write_data(pp->port, byte);
112 pp->lastbyte = byte;
113}
114
115static inline int getmiso(struct spi_device *spi)
116{
117 struct butterfly *pp = spidev_to_pp(spi);
118 int value;
119 u8 bit;
120
121 bit = spi_miso_bit;
122
123
124 value = !(parport_read_status(pp->port) & bit);
125 return (bit == PARPORT_STATUS_BUSY) ? value : !value;
126}
127
128static void butterfly_chipselect(struct spi_device *spi, int value)
129{
130 struct butterfly *pp = spidev_to_pp(spi);
131
132
133 if (value != BITBANG_CS_INACTIVE)
134 setsck(spi, spi->mode & SPI_CPOL);
135
136
137
138
139
140 if (spi_cs_bit == PARPORT_CONTROL_INIT)
141 value = !value;
142
143 parport_frob_control(pp->port, spi_cs_bit, value ? spi_cs_bit : 0);
144}
145
146
147
148
149#define spidelay(X) do{}while(0)
150
151
152#include "spi_bitbang_txrx.h"
153
154static u32
155butterfly_txrx_word_mode0(struct spi_device *spi,
156 unsigned nsecs,
157 u32 word, u8 bits)
158{
159 return bitbang_txrx_be_cpha0(spi, nsecs, 0, 0, word, bits);
160}
161
162
163
164
165static struct mtd_partition partitions[] = { {
166
167
168
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170
171
172
173 .name = "bookkeeping",
174 .offset = 0,
175 .size = (8 + 248) * 264,
176
177}, {
178
179
180
181 .name = "filesystem",
182 .offset = MTDPART_OFS_APPEND,
183 .size = MTDPART_SIZ_FULL,
184} };
185
186static struct flash_platform_data flash = {
187 .name = "butterflash",
188 .parts = partitions,
189 .nr_parts = ARRAY_SIZE(partitions),
190};
191
192
193
194static struct butterfly *butterfly;
195
196static void butterfly_attach(struct parport *p)
197{
198 struct pardevice *pd;
199 int status;
200 struct butterfly *pp;
201 struct spi_master *master;
202 struct device *dev = p->physport->dev;
203
204 if (butterfly || !dev)
205 return;
206
207
208
209
210
211 master = spi_alloc_master(dev, sizeof *pp);
212 if (!master) {
213 status = -ENOMEM;
214 goto done;
215 }
216 pp = spi_master_get_devdata(master);
217
218
219
220
221
222
223
224 master->bus_num = 42;
225 master->num_chipselect = 2;
226
227 pp->bitbang.master = spi_master_get(master);
228 pp->bitbang.chipselect = butterfly_chipselect;
229 pp->bitbang.txrx_word[SPI_MODE_0] = butterfly_txrx_word_mode0;
230
231
232
233
234 pp->port = p;
235 pd = parport_register_device(p, "spi_butterfly",
236 NULL, NULL, NULL,
237 0 , pp);
238 if (!pd) {
239 status = -ENOMEM;
240 goto clean0;
241 }
242 pp->pd = pd;
243
244 status = parport_claim(pd);
245 if (status < 0)
246 goto clean1;
247
248
249
250
251 pr_debug("%s: powerup/reset Butterfly\n", p->name);
252
253
254 parport_frob_control(pp->port, spi_cs_bit, 0);
255
256
257
258
259 pp->lastbyte |= vcc_bits;
260 parport_write_data(pp->port, pp->lastbyte);
261 msleep(5);
262
263
264 pp->lastbyte |= butterfly_nreset;
265 parport_write_data(pp->port, pp->lastbyte);
266 msleep(100);
267
268
269
270
271
272 status = spi_bitbang_start(&pp->bitbang);
273 if (status < 0)
274 goto clean2;
275
276
277
278
279
280
281 pp->info[0].max_speed_hz = 15 * 1000 * 1000;
282 strcpy(pp->info[0].modalias, "mtd_dataflash");
283 pp->info[0].platform_data = &flash;
284 pp->info[0].chip_select = 1;
285 pp->info[0].controller_data = pp;
286 pp->dataflash = spi_new_device(pp->bitbang.master, &pp->info[0]);
287 if (pp->dataflash)
288 pr_debug("%s: dataflash at %s\n", p->name,
289 dev_name(&pp->dataflash->dev));
290
291
292 pr_info("%s: AVR Butterfly\n", p->name);
293 butterfly = pp;
294 return;
295
296clean2:
297
298 parport_write_data(pp->port, 0);
299
300 parport_release(pp->pd);
301clean1:
302 parport_unregister_device(pd);
303clean0:
304 (void) spi_master_put(pp->bitbang.master);
305done:
306 pr_debug("%s: butterfly probe, fail %d\n", p->name, status);
307}
308
309static void butterfly_detach(struct parport *p)
310{
311 struct butterfly *pp;
312 int status;
313
314
315
316
317
318 if (!butterfly || butterfly->port != p)
319 return;
320 pp = butterfly;
321 butterfly = NULL;
322
323
324 status = spi_bitbang_stop(&pp->bitbang);
325
326
327 parport_write_data(pp->port, 0);
328 msleep(10);
329
330 parport_release(pp->pd);
331 parport_unregister_device(pp->pd);
332
333 (void) spi_master_put(pp->bitbang.master);
334}
335
336static struct parport_driver butterfly_driver = {
337 .name = "spi_butterfly",
338 .attach = butterfly_attach,
339 .detach = butterfly_detach,
340};
341
342
343static int __init butterfly_init(void)
344{
345 return parport_register_driver(&butterfly_driver);
346}
347device_initcall(butterfly_init);
348
349static void __exit butterfly_exit(void)
350{
351 parport_unregister_driver(&butterfly_driver);
352}
353module_exit(butterfly_exit);
354
355MODULE_DESCRIPTION("Parport Adapter driver for AVR Butterfly");
356MODULE_LICENSE("GPL");
357