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1/*
2 * parport-to-butterfly adapter
3 *
4 * Copyright (C) 2005 David Brownell
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
10 *
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
19 */
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/*
35 * This uses SPI to talk with an "AVR Butterfly", which is a $US20 card
36 * with a battery powered AVR microcontroller and lots of goodies. You
37 * can use GCC to develop firmware for this.
38 *
39 * See Documentation/spi/butterfly for information about how to build
40 * and use this custom parallel port cable.
41 */
42
43
44/* DATA output bits (pins 2..9 == D0..D7) */
45#define butterfly_nreset (1 << 1) /* pin 3 */
46
47#define spi_sck_bit (1 << 0) /* pin 2 */
48#define spi_mosi_bit (1 << 7) /* pin 9 */
49
50#define vcc_bits ((1 << 6) | (1 << 5)) /* pins 7, 8 */
51
52/* STATUS input bits */
53#define spi_miso_bit PARPORT_STATUS_BUSY /* pin 11 */
54
55/* CONTROL output bits */
56#define spi_cs_bit PARPORT_CONTROL_SELECT /* pin 17 */
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 /* REVISIT ... for now, this must be first */
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 /* only STATUS_BUSY is NOT negated */
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 /* set default clock polarity */
133 if (value != BITBANG_CS_INACTIVE)
134 setsck(spi, spi->mode & SPI_CPOL);
135
136 /* here, value == "activate or not";
137 * most PARPORT_CONTROL_* bits are negated, so we must
138 * morph it to value == "bit value to write in control register"
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/* we only needed to implement one mode here, and choose SPI_MODE_0 */
148
149#define spidelay(X) do{}while(0)
150//#define spidelay ndelay
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/* override default partitioning with cmdlinepart */
165static struct mtd_partition partitions[] = { {
166 /* JFFS2 wants partitions of 4*N blocks for this device,
167 * so sectors 0 and 1 can't be partitions by themselves.
168 */
169
170 /* sector 0 = 8 pages * 264 bytes/page (1 block)
171 * sector 1 = 248 pages * 264 bytes/page
172 */
173 .name = "bookkeeping", // 66 KB
174 .offset = 0,
175 .size = (8 + 248) * 264,
176// .mask_flags = MTD_WRITEABLE,
177}, {
178 /* sector 2 = 256 pages * 264 bytes/page
179 * sectors 3-5 = 512 pages * 264 bytes/page
180 */
181 .name = "filesystem", // 462 KB
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/* REVISIT remove this ugly global and its "only one" limitation */
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 /* REVISIT: this just _assumes_ a butterfly is there ... no probe,
208 * and no way to be selective about what it binds to.
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 * SPI and bitbang hookup
220 *
221 * use default setup(), cleanup(), and transfer() methods; and
222 * only bother implementing mode 0. Start it later.
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 * parport hookup
233 */
234 pp->port = p;
235 pd = parport_register_device(p, "spi_butterfly",
236 NULL, NULL, NULL,
237 0 /* FLAGS */, 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 * Butterfly reset, powerup, run firmware
250 */
251 pr_debug("%s: powerup/reset Butterfly\n", p->name);
252
253 /* nCS for dataflash (this bit is inverted on output) */
254 parport_frob_control(pp->port, spi_cs_bit, 0);
255
256 /* stabilize power with chip in reset (nRESET), and
257 * spi_sck_bit clear (CPOL=0)
258 */
259 pp->lastbyte |= vcc_bits;
260 parport_write_data(pp->port, pp->lastbyte);
261 msleep(5);
262
263 /* take it out of reset; assume long reset delay */
264 pp->lastbyte |= butterfly_nreset;
265 parport_write_data(pp->port, pp->lastbyte);
266 msleep(100);
267
268
269 /*
270 * Start SPI ... for now, hide that we're two physical busses.
271 */
272 status = spi_bitbang_start(&pp->bitbang);
273 if (status < 0)
274 goto clean2;
275
276 /* Bus 1 lets us talk to at45db041b (firmware disables AVR SPI), AVR
277 * (firmware resets at45, acts as spi slave) or neither (we ignore
278 * both, AVR uses AT45). Here we expect firmware for the first option.
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 // dev_info(_what?_, ...)
292 pr_info("%s: AVR Butterfly\n", p->name);
293 butterfly = pp;
294 return;
295
296clean2:
297 /* turn off VCC */
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 /* FIXME this global is ugly ... but, how to quickly get from
315 * the parport to the "struct butterfly" associated with it?
316 * "old school" driver-internal device lists?
317 */
318 if (!butterfly || butterfly->port != p)
319 return;
320 pp = butterfly;
321 butterfly = NULL;
322
323 /* stop() unregisters child devices too */
324 status = spi_bitbang_stop(&pp->bitbang);
325
326 /* turn off VCC */
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");
1/*
2 * parport-to-butterfly adapter
3 *
4 * Copyright (C) 2005 David Brownell
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
10 *
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
19 */
20#include <linux/kernel.h>
21#include <linux/init.h>
22#include <linux/delay.h>
23#include <linux/module.h>
24#include <linux/device.h>
25#include <linux/parport.h>
26
27#include <linux/sched.h>
28#include <linux/spi/spi.h>
29#include <linux/spi/spi_bitbang.h>
30#include <linux/spi/flash.h>
31
32#include <linux/mtd/partitions.h>
33
34
35/*
36 * This uses SPI to talk with an "AVR Butterfly", which is a $US20 card
37 * with a battery powered AVR microcontroller and lots of goodies. You
38 * can use GCC to develop firmware for this.
39 *
40 * See Documentation/spi/butterfly for information about how to build
41 * and use this custom parallel port cable.
42 */
43
44
45/* DATA output bits (pins 2..9 == D0..D7) */
46#define butterfly_nreset (1 << 1) /* pin 3 */
47
48#define spi_sck_bit (1 << 0) /* pin 2 */
49#define spi_mosi_bit (1 << 7) /* pin 9 */
50
51#define vcc_bits ((1 << 6) | (1 << 5)) /* pins 7, 8 */
52
53/* STATUS input bits */
54#define spi_miso_bit PARPORT_STATUS_BUSY /* pin 11 */
55
56/* CONTROL output bits */
57#define spi_cs_bit PARPORT_CONTROL_SELECT /* pin 17 */
58
59
60
61static inline struct butterfly *spidev_to_pp(struct spi_device *spi)
62{
63 return spi->controller_data;
64}
65
66
67struct butterfly {
68 /* REVISIT ... for now, this must be first */
69 struct spi_bitbang bitbang;
70
71 struct parport *port;
72 struct pardevice *pd;
73
74 u8 lastbyte;
75
76 struct spi_device *dataflash;
77 struct spi_device *butterfly;
78 struct spi_board_info info[2];
79
80};
81
82/*----------------------------------------------------------------------*/
83
84static inline void
85setsck(struct spi_device *spi, int is_on)
86{
87 struct butterfly *pp = spidev_to_pp(spi);
88 u8 bit, byte = pp->lastbyte;
89
90 bit = spi_sck_bit;
91
92 if (is_on)
93 byte |= bit;
94 else
95 byte &= ~bit;
96 parport_write_data(pp->port, byte);
97 pp->lastbyte = byte;
98}
99
100static inline void
101setmosi(struct spi_device *spi, int is_on)
102{
103 struct butterfly *pp = spidev_to_pp(spi);
104 u8 bit, byte = pp->lastbyte;
105
106 bit = spi_mosi_bit;
107
108 if (is_on)
109 byte |= bit;
110 else
111 byte &= ~bit;
112 parport_write_data(pp->port, byte);
113 pp->lastbyte = byte;
114}
115
116static inline int getmiso(struct spi_device *spi)
117{
118 struct butterfly *pp = spidev_to_pp(spi);
119 int value;
120 u8 bit;
121
122 bit = spi_miso_bit;
123
124 /* only STATUS_BUSY is NOT negated */
125 value = !(parport_read_status(pp->port) & bit);
126 return (bit == PARPORT_STATUS_BUSY) ? value : !value;
127}
128
129static void butterfly_chipselect(struct spi_device *spi, int value)
130{
131 struct butterfly *pp = spidev_to_pp(spi);
132
133 /* set default clock polarity */
134 if (value != BITBANG_CS_INACTIVE)
135 setsck(spi, spi->mode & SPI_CPOL);
136
137 /* here, value == "activate or not";
138 * most PARPORT_CONTROL_* bits are negated, so we must
139 * morph it to value == "bit value to write in control register"
140 */
141 if (spi_cs_bit == PARPORT_CONTROL_INIT)
142 value = !value;
143
144 parport_frob_control(pp->port, spi_cs_bit, value ? spi_cs_bit : 0);
145}
146
147
148/* we only needed to implement one mode here, and choose SPI_MODE_0 */
149
150#define spidelay(X) do { } while (0)
151/* #define spidelay ndelay */
152
153#include "spi-bitbang-txrx.h"
154
155static u32
156butterfly_txrx_word_mode0(struct spi_device *spi,
157 unsigned nsecs,
158 u32 word, u8 bits)
159{
160 return bitbang_txrx_be_cpha0(spi, nsecs, 0, 0, word, bits);
161}
162
163/*----------------------------------------------------------------------*/
164
165/* override default partitioning with cmdlinepart */
166static struct mtd_partition partitions[] = { {
167 /* JFFS2 wants partitions of 4*N blocks for this device,
168 * so sectors 0 and 1 can't be partitions by themselves.
169 */
170
171 /* sector 0 = 8 pages * 264 bytes/page (1 block)
172 * sector 1 = 248 pages * 264 bytes/page
173 */
174 .name = "bookkeeping", /* 66 KB */
175 .offset = 0,
176 .size = (8 + 248) * 264,
177 /* .mask_flags = MTD_WRITEABLE, */
178}, {
179 /* sector 2 = 256 pages * 264 bytes/page
180 * sectors 3-5 = 512 pages * 264 bytes/page
181 */
182 .name = "filesystem", /* 462 KB */
183 .offset = MTDPART_OFS_APPEND,
184 .size = MTDPART_SIZ_FULL,
185} };
186
187static struct flash_platform_data flash = {
188 .name = "butterflash",
189 .parts = partitions,
190 .nr_parts = ARRAY_SIZE(partitions),
191};
192
193
194/* REVISIT remove this ugly global and its "only one" limitation */
195static struct butterfly *butterfly;
196
197static void butterfly_attach(struct parport *p)
198{
199 struct pardevice *pd;
200 int status;
201 struct butterfly *pp;
202 struct spi_master *master;
203 struct device *dev = p->physport->dev;
204
205 if (butterfly || !dev)
206 return;
207
208 /* REVISIT: this just _assumes_ a butterfly is there ... no probe,
209 * and no way to be selective about what it binds to.
210 */
211
212 master = spi_alloc_master(dev, sizeof(*pp));
213 if (!master) {
214 status = -ENOMEM;
215 goto done;
216 }
217 pp = spi_master_get_devdata(master);
218
219 /*
220 * SPI and bitbang hookup
221 *
222 * use default setup(), cleanup(), and transfer() methods; and
223 * only bother implementing mode 0. Start it later.
224 */
225 master->bus_num = 42;
226 master->num_chipselect = 2;
227
228 pp->bitbang.master = master;
229 pp->bitbang.chipselect = butterfly_chipselect;
230 pp->bitbang.txrx_word[SPI_MODE_0] = butterfly_txrx_word_mode0;
231
232 /*
233 * parport hookup
234 */
235 pp->port = p;
236 pd = parport_register_device(p, "spi_butterfly",
237 NULL, NULL, NULL,
238 0 /* FLAGS */, pp);
239 if (!pd) {
240 status = -ENOMEM;
241 goto clean0;
242 }
243 pp->pd = pd;
244
245 status = parport_claim(pd);
246 if (status < 0)
247 goto clean1;
248
249 /*
250 * Butterfly reset, powerup, run firmware
251 */
252 pr_debug("%s: powerup/reset Butterfly\n", p->name);
253
254 /* nCS for dataflash (this bit is inverted on output) */
255 parport_frob_control(pp->port, spi_cs_bit, 0);
256
257 /* stabilize power with chip in reset (nRESET), and
258 * spi_sck_bit clear (CPOL=0)
259 */
260 pp->lastbyte |= vcc_bits;
261 parport_write_data(pp->port, pp->lastbyte);
262 msleep(5);
263
264 /* take it out of reset; assume long reset delay */
265 pp->lastbyte |= butterfly_nreset;
266 parport_write_data(pp->port, pp->lastbyte);
267 msleep(100);
268
269
270 /*
271 * Start SPI ... for now, hide that we're two physical busses.
272 */
273 status = spi_bitbang_start(&pp->bitbang);
274 if (status < 0)
275 goto clean2;
276
277 /* Bus 1 lets us talk to at45db041b (firmware disables AVR SPI), AVR
278 * (firmware resets at45, acts as spi slave) or neither (we ignore
279 * both, AVR uses AT45). Here we expect firmware for the first option.
280 */
281
282 pp->info[0].max_speed_hz = 15 * 1000 * 1000;
283 strcpy(pp->info[0].modalias, "mtd_dataflash");
284 pp->info[0].platform_data = &flash;
285 pp->info[0].chip_select = 1;
286 pp->info[0].controller_data = pp;
287 pp->dataflash = spi_new_device(pp->bitbang.master, &pp->info[0]);
288 if (pp->dataflash)
289 pr_debug("%s: dataflash at %s\n", p->name,
290 dev_name(&pp->dataflash->dev));
291
292 pr_info("%s: AVR Butterfly\n", p->name);
293 butterfly = pp;
294 return;
295
296clean2:
297 /* turn off VCC */
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
313 /* FIXME this global is ugly ... but, how to quickly get from
314 * the parport to the "struct butterfly" associated with it?
315 * "old school" driver-internal device lists?
316 */
317 if (!butterfly || butterfly->port != p)
318 return;
319 pp = butterfly;
320 butterfly = NULL;
321
322 /* stop() unregisters child devices too */
323 spi_bitbang_stop(&pp->bitbang);
324
325 /* turn off VCC */
326 parport_write_data(pp->port, 0);
327 msleep(10);
328
329 parport_release(pp->pd);
330 parport_unregister_device(pp->pd);
331
332 (void) spi_master_put(pp->bitbang.master);
333}
334
335static struct parport_driver butterfly_driver = {
336 .name = "spi_butterfly",
337 .attach = butterfly_attach,
338 .detach = butterfly_detach,
339};
340
341
342static int __init butterfly_init(void)
343{
344 return parport_register_driver(&butterfly_driver);
345}
346device_initcall(butterfly_init);
347
348static void __exit butterfly_exit(void)
349{
350 parport_unregister_driver(&butterfly_driver);
351}
352module_exit(butterfly_exit);
353
354MODULE_DESCRIPTION("Parport Adapter driver for AVR Butterfly");
355MODULE_LICENSE("GPL");