1 /*
2 * Simple synchronous serial port driver for ETRAX FS and ARTPEC-3.
3 *
4 * Copyright (c) 2005, 2008 Axis Communications AB
5 * Author: Mikael Starvik
6 *
7 */
8
9 #include <linux/module.h>
10 #include <linux/kernel.h>
11 #include <linux/types.h>
12 #include <linux/errno.h>
13 #include <linux/major.h>
14 #include <linux/sched.h>
15 #include <linux/mutex.h>
16 #include <linux/interrupt.h>
17 #include <linux/poll.h>
18 #include <linux/fs.h>
19 #include <linux/cdev.h>
20 #include <linux/device.h>
21 #include <linux/wait.h>
22
23 #include <asm/io.h>
24 #include <mach/dma.h>
25 #include <pinmux.h>
26 #include <hwregs/reg_rdwr.h>
27 #include <hwregs/sser_defs.h>
28 #include <hwregs/timer_defs.h>
29 #include <hwregs/dma_defs.h>
30 #include <hwregs/dma.h>
31 #include <hwregs/intr_vect_defs.h>
32 #include <hwregs/intr_vect.h>
33 #include <hwregs/reg_map.h>
34 #include <asm/sync_serial.h>
35
36
37 /* The receiver is a bit tricky because of the continuous stream of data.*/
38 /* */
39 /* Three DMA descriptors are linked together. Each DMA descriptor is */
40 /* responsible for port->bufchunk of a common buffer. */
41 /* */
42 /* +---------------------------------------------+ */
43 /* | +----------+ +----------+ +----------+ | */
44 /* +-> | Descr[0] |-->| Descr[1] |-->| Descr[2] |-+ */
45 /* +----------+ +----------+ +----------+ */
46 /* | | | */
47 /* v v v */
48 /* +-------------------------------------+ */
49 /* | BUFFER | */
50 /* +-------------------------------------+ */
51 /* |<- data_avail ->| */
52 /* readp writep */
53 /* */
54 /* If the application keeps up the pace readp will be right after writep.*/
55 /* If the application can't keep the pace we have to throw away data. */
56 /* The idea is that readp should be ready with the data pointed out by */
57 /* Descr[i] when the DMA has filled in Descr[i+1]. */
58 /* Otherwise we will discard */
59 /* the rest of the data pointed out by Descr1 and set readp to the start */
60 /* of Descr2 */
61
62 /* IN_BUFFER_SIZE should be a multiple of 6 to make sure that 24 bit */
63 /* words can be handled */
64 #define IN_DESCR_SIZE SSP_INPUT_CHUNK_SIZE
65 #define NBR_IN_DESCR (8*6)
66 #define IN_BUFFER_SIZE (IN_DESCR_SIZE * NBR_IN_DESCR)
67
68 #define NBR_OUT_DESCR 8
69 #define OUT_BUFFER_SIZE (1024 * NBR_OUT_DESCR)
70
71 #define DEFAULT_FRAME_RATE 0
72 #define DEFAULT_WORD_RATE 7
73
74 /* To be removed when we move to pure udev. */
75 #define SYNC_SERIAL_MAJOR 125
76
77 /* NOTE: Enabling some debug will likely cause overrun or underrun,
78 * especially if manual mode is used.
79 */
80 #define DEBUG(x)
81 #define DEBUGREAD(x)
82 #define DEBUGWRITE(x)
83 #define DEBUGPOLL(x)
84 #define DEBUGRXINT(x)
85 #define DEBUGTXINT(x)
86 #define DEBUGTRDMA(x)
87 #define DEBUGOUTBUF(x)
88
89 enum syncser_irq_setup {
90 no_irq_setup = 0,
91 dma_irq_setup = 1,
92 manual_irq_setup = 2,
93 };
94
95 struct sync_port {
96 unsigned long regi_sser;
97 unsigned long regi_dmain;
98 unsigned long regi_dmaout;
99
100 /* Interrupt vectors. */
101 unsigned long dma_in_intr_vect; /* Used for DMA in. */
102 unsigned long dma_out_intr_vect; /* Used for DMA out. */
103 unsigned long syncser_intr_vect; /* Used when no DMA. */
104
105 /* DMA number for in and out. */
106 unsigned int dma_in_nbr;
107 unsigned int dma_out_nbr;
108
109 /* DMA owner. */
110 enum dma_owner req_dma;
111
112 char started; /* 1 if port has been started */
113 char port_nbr; /* Port 0 or 1 */
114 char busy; /* 1 if port is busy */
115
116 char enabled; /* 1 if port is enabled */
117 char use_dma; /* 1 if port uses dma */
118 char tr_running;
119
120 enum syncser_irq_setup init_irqs;
121 int output;
122 int input;
123
124 /* Next byte to be read by application */
125 unsigned char *readp;
126 /* Next byte to be written by etrax */
127 unsigned char *writep;
128
129 unsigned int in_buffer_size;
130 unsigned int in_buffer_len;
131 unsigned int inbufchunk;
132 /* Data buffers for in and output. */
133 unsigned char out_buffer[OUT_BUFFER_SIZE] __aligned(32);
134 unsigned char in_buffer[IN_BUFFER_SIZE] __aligned(32);
135 unsigned char flip[IN_BUFFER_SIZE] __aligned(32);
136 struct timespec timestamp[NBR_IN_DESCR];
137 struct dma_descr_data *next_rx_desc;
138 struct dma_descr_data *prev_rx_desc;
139
140 struct timeval last_timestamp;
141 int read_ts_idx;
142 int write_ts_idx;
143
144 /* Pointer to the first available descriptor in the ring,
145 * unless active_tr_descr == catch_tr_descr and a dma
146 * transfer is active */
147 struct dma_descr_data *active_tr_descr;
148
149 /* Pointer to the first allocated descriptor in the ring */
150 struct dma_descr_data *catch_tr_descr;
151
152 /* Pointer to the descriptor with the current end-of-list */
153 struct dma_descr_data *prev_tr_descr;
154 int full;
155
156 /* Pointer to the first byte being read by DMA
157 * or current position in out_buffer if not using DMA. */
158 unsigned char *out_rd_ptr;
159
160 /* Number of bytes currently locked for being read by DMA */
161 int out_buf_count;
162
163 dma_descr_context in_context __aligned(32);
164 dma_descr_context out_context __aligned(32);
165 dma_descr_data in_descr[NBR_IN_DESCR] __aligned(16);
166 dma_descr_data out_descr[NBR_OUT_DESCR] __aligned(16);
167
168 wait_queue_head_t out_wait_q;
169 wait_queue_head_t in_wait_q;
170
171 spinlock_t lock;
172 };
173
174 static DEFINE_MUTEX(sync_serial_mutex);
175 static int etrax_sync_serial_init(void);
176 static void initialize_port(int portnbr);
177 static inline int sync_data_avail(struct sync_port *port);
178
179 static int sync_serial_open(struct inode *, struct file *);
180 static int sync_serial_release(struct inode *, struct file *);
181 static unsigned int sync_serial_poll(struct file *filp, poll_table *wait);
182
183 static long sync_serial_ioctl(struct file *file,
184 unsigned int cmd, unsigned long arg);
185 static int sync_serial_ioctl_unlocked(struct file *file,
186 unsigned int cmd, unsigned long arg);
187 static ssize_t sync_serial_write(struct file *file, const char __user *buf,
188 size_t count, loff_t *ppos);
189 static ssize_t sync_serial_read(struct file *file, char __user *buf,
190 size_t count, loff_t *ppos);
191
192 #if ((defined(CONFIG_ETRAX_SYNCHRONOUS_SERIAL_PORT0) && \
193 defined(CONFIG_ETRAX_SYNCHRONOUS_SERIAL0_DMA)) || \
194 (defined(CONFIG_ETRAX_SYNCHRONOUS_SERIAL_PORT1) && \
195 defined(CONFIG_ETRAX_SYNCHRONOUS_SERIAL1_DMA)))
196 #define SYNC_SER_DMA
197 #else
198 #define SYNC_SER_MANUAL
199 #endif
200
201 #ifdef SYNC_SER_DMA
202 static void start_dma_out(struct sync_port *port, const char *data, int count);
203 static void start_dma_in(struct sync_port *port);
204 static irqreturn_t tr_interrupt(int irq, void *dev_id);
205 static irqreturn_t rx_interrupt(int irq, void *dev_id);
206 #endif
207 #ifdef SYNC_SER_MANUAL
208 static void send_word(struct sync_port *port);
209 static irqreturn_t manual_interrupt(int irq, void *dev_id);
210 #endif
211
212 #define artpec_pinmux_alloc_fixed crisv32_pinmux_alloc_fixed
213 #define artpec_request_dma crisv32_request_dma
214 #define artpec_free_dma crisv32_free_dma
215
216 #ifdef CONFIG_ETRAXFS
217 /* ETRAX FS */
218 #define DMA_OUT_NBR0 SYNC_SER0_TX_DMA_NBR
219 #define DMA_IN_NBR0 SYNC_SER0_RX_DMA_NBR
220 #define DMA_OUT_NBR1 SYNC_SER1_TX_DMA_NBR
221 #define DMA_IN_NBR1 SYNC_SER1_RX_DMA_NBR
222 #define PINMUX_SSER0 pinmux_sser0
223 #define PINMUX_SSER1 pinmux_sser1
224 #define SYNCSER_INST0 regi_sser0
225 #define SYNCSER_INST1 regi_sser1
226 #define SYNCSER_INTR_VECT0 SSER0_INTR_VECT
227 #define SYNCSER_INTR_VECT1 SSER1_INTR_VECT
228 #define OUT_DMA_INST0 regi_dma4
229 #define IN_DMA_INST0 regi_dma5
230 #define DMA_OUT_INTR_VECT0 DMA4_INTR_VECT
231 #define DMA_OUT_INTR_VECT1 DMA7_INTR_VECT
232 #define DMA_IN_INTR_VECT0 DMA5_INTR_VECT
233 #define DMA_IN_INTR_VECT1 DMA6_INTR_VECT
234 #define REQ_DMA_SYNCSER0 dma_sser0
235 #define REQ_DMA_SYNCSER1 dma_sser1
236 #if defined(CONFIG_ETRAX_SYNCHRONOUS_SERIAL1_DMA)
237 #define PORT1_DMA 1
238 #else
239 #define PORT1_DMA 0
240 #endif
241 #elif defined(CONFIG_CRIS_MACH_ARTPEC3)
242 /* ARTPEC-3 */
243 #define DMA_OUT_NBR0 SYNC_SER_TX_DMA_NBR
244 #define DMA_IN_NBR0 SYNC_SER_RX_DMA_NBR
245 #define PINMUX_SSER0 pinmux_sser
246 #define SYNCSER_INST0 regi_sser
247 #define SYNCSER_INTR_VECT0 SSER_INTR_VECT
248 #define OUT_DMA_INST0 regi_dma6
249 #define IN_DMA_INST0 regi_dma7
250 #define DMA_OUT_INTR_VECT0 DMA6_INTR_VECT
251 #define DMA_IN_INTR_VECT0 DMA7_INTR_VECT
252 #define REQ_DMA_SYNCSER0 dma_sser
253 #define REQ_DMA_SYNCSER1 dma_sser
254 #endif
255
256 #if defined(CONFIG_ETRAX_SYNCHRONOUS_SERIAL0_DMA)
257 #define PORT0_DMA 1
258 #else
259 #define PORT0_DMA 0
260 #endif
261
262 /* The ports */
263 static struct sync_port ports[] = {
264 {
265 .regi_sser = SYNCSER_INST0,
266 .regi_dmaout = OUT_DMA_INST0,
267 .regi_dmain = IN_DMA_INST0,
268 .use_dma = PORT0_DMA,
269 .dma_in_intr_vect = DMA_IN_INTR_VECT0,
270 .dma_out_intr_vect = DMA_OUT_INTR_VECT0,
271 .dma_in_nbr = DMA_IN_NBR0,
272 .dma_out_nbr = DMA_OUT_NBR0,
273 .req_dma = REQ_DMA_SYNCSER0,
274 .syncser_intr_vect = SYNCSER_INTR_VECT0,
275 },
276 #ifdef CONFIG_ETRAXFS
277 {
278 .regi_sser = SYNCSER_INST1,
279 .regi_dmaout = regi_dma6,
280 .regi_dmain = regi_dma7,
281 .use_dma = PORT1_DMA,
282 .dma_in_intr_vect = DMA_IN_INTR_VECT1,
283 .dma_out_intr_vect = DMA_OUT_INTR_VECT1,
284 .dma_in_nbr = DMA_IN_NBR1,
285 .dma_out_nbr = DMA_OUT_NBR1,
286 .req_dma = REQ_DMA_SYNCSER1,
287 .syncser_intr_vect = SYNCSER_INTR_VECT1,
288 },
289 #endif
290 };
291
292 #define NBR_PORTS ARRAY_SIZE(ports)
293
294 static const struct file_operations syncser_fops = {
295 .owner = THIS_MODULE,
296 .write = sync_serial_write,
297 .read = sync_serial_read,
298 .poll = sync_serial_poll,
299 .unlocked_ioctl = sync_serial_ioctl,
300 .open = sync_serial_open,
301 .release = sync_serial_release,
302 .llseek = noop_llseek,
303 };
304
305 static dev_t syncser_first;
306 static int minor_count = NBR_PORTS;
307 #define SYNCSER_NAME "syncser"
308 static struct cdev *syncser_cdev;
309 static struct class *syncser_class;
310
sync_serial_start_port(struct sync_port * port)311 static void sync_serial_start_port(struct sync_port *port)
312 {
313 reg_sser_rw_cfg cfg = REG_RD(sser, port->regi_sser, rw_cfg);
314 reg_sser_rw_tr_cfg tr_cfg =
315 REG_RD(sser, port->regi_sser, rw_tr_cfg);
316 reg_sser_rw_rec_cfg rec_cfg =
317 REG_RD(sser, port->regi_sser, rw_rec_cfg);
318 cfg.en = regk_sser_yes;
319 tr_cfg.tr_en = regk_sser_yes;
320 rec_cfg.rec_en = regk_sser_yes;
321 REG_WR(sser, port->regi_sser, rw_cfg, cfg);
322 REG_WR(sser, port->regi_sser, rw_tr_cfg, tr_cfg);
323 REG_WR(sser, port->regi_sser, rw_rec_cfg, rec_cfg);
324 port->started = 1;
325 }
326
initialize_port(int portnbr)327 static void __init initialize_port(int portnbr)
328 {
329 struct sync_port *port = &ports[portnbr];
330 reg_sser_rw_cfg cfg = { 0 };
331 reg_sser_rw_frm_cfg frm_cfg = { 0 };
332 reg_sser_rw_tr_cfg tr_cfg = { 0 };
333 reg_sser_rw_rec_cfg rec_cfg = { 0 };
334
335 DEBUG(pr_info("Init sync serial port %d\n", portnbr));
336
337 port->port_nbr = portnbr;
338 port->init_irqs = no_irq_setup;
339
340 port->out_rd_ptr = port->out_buffer;
341 port->out_buf_count = 0;
342
343 port->output = 1;
344 port->input = 0;
345
346 port->readp = port->flip;
347 port->writep = port->flip;
348 port->in_buffer_size = IN_BUFFER_SIZE;
349 port->in_buffer_len = 0;
350 port->inbufchunk = IN_DESCR_SIZE;
351
352 port->read_ts_idx = 0;
353 port->write_ts_idx = 0;
354
355 init_waitqueue_head(&port->out_wait_q);
356 init_waitqueue_head(&port->in_wait_q);
357
358 spin_lock_init(&port->lock);
359
360 cfg.out_clk_src = regk_sser_intern_clk;
361 cfg.out_clk_pol = regk_sser_pos;
362 cfg.clk_od_mode = regk_sser_no;
363 cfg.clk_dir = regk_sser_out;
364 cfg.gate_clk = regk_sser_no;
365 cfg.base_freq = regk_sser_f29_493;
366 cfg.clk_div = 256;
367 REG_WR(sser, port->regi_sser, rw_cfg, cfg);
368
369 frm_cfg.wordrate = DEFAULT_WORD_RATE;
370 frm_cfg.type = regk_sser_edge;
371 frm_cfg.frame_pin_dir = regk_sser_out;
372 frm_cfg.frame_pin_use = regk_sser_frm;
373 frm_cfg.status_pin_dir = regk_sser_in;
374 frm_cfg.status_pin_use = regk_sser_hold;
375 frm_cfg.out_on = regk_sser_tr;
376 frm_cfg.tr_delay = 1;
377 REG_WR(sser, port->regi_sser, rw_frm_cfg, frm_cfg);
378
379 tr_cfg.urun_stop = regk_sser_no;
380 tr_cfg.sample_size = 7;
381 tr_cfg.sh_dir = regk_sser_msbfirst;
382 tr_cfg.use_dma = port->use_dma ? regk_sser_yes : regk_sser_no;
383 #if 0
384 tr_cfg.rate_ctrl = regk_sser_bulk;
385 tr_cfg.data_pin_use = regk_sser_dout;
386 #else
387 tr_cfg.rate_ctrl = regk_sser_iso;
388 tr_cfg.data_pin_use = regk_sser_dout;
389 #endif
390 tr_cfg.bulk_wspace = 1;
391 REG_WR(sser, port->regi_sser, rw_tr_cfg, tr_cfg);
392
393 rec_cfg.sample_size = 7;
394 rec_cfg.sh_dir = regk_sser_msbfirst;
395 rec_cfg.use_dma = port->use_dma ? regk_sser_yes : regk_sser_no;
396 rec_cfg.fifo_thr = regk_sser_inf;
397 REG_WR(sser, port->regi_sser, rw_rec_cfg, rec_cfg);
398
399 #ifdef SYNC_SER_DMA
400 {
401 int i;
402 /* Setup the descriptor ring for dma out/transmit. */
403 for (i = 0; i < NBR_OUT_DESCR; i++) {
404 dma_descr_data *descr = &port->out_descr[i];
405 descr->wait = 0;
406 descr->intr = 1;
407 descr->eol = 0;
408 descr->out_eop = 0;
409 descr->next =
410 (dma_descr_data *)virt_to_phys(&descr[i+1]);
411 }
412 }
413
414 /* Create a ring from the list. */
415 port->out_descr[NBR_OUT_DESCR-1].next =
416 (dma_descr_data *)virt_to_phys(&port->out_descr[0]);
417
418 /* Setup context for traversing the ring. */
419 port->active_tr_descr = &port->out_descr[0];
420 port->prev_tr_descr = &port->out_descr[NBR_OUT_DESCR-1];
421 port->catch_tr_descr = &port->out_descr[0];
422 #endif
423 }
424
sync_data_avail(struct sync_port * port)425 static inline int sync_data_avail(struct sync_port *port)
426 {
427 return port->in_buffer_len;
428 }
429
sync_serial_open(struct inode * inode,struct file * file)430 static int sync_serial_open(struct inode *inode, struct file *file)
431 {
432 int ret = 0;
433 int dev = iminor(inode);
434 struct sync_port *port;
435 #ifdef SYNC_SER_DMA
436 reg_dma_rw_cfg cfg = { .en = regk_dma_yes };
437 reg_dma_rw_intr_mask intr_mask = { .data = regk_dma_yes };
438 #endif
439
440 DEBUG(pr_debug("Open sync serial port %d\n", dev));
441
442 if (dev < 0 || dev >= NBR_PORTS || !ports[dev].enabled) {
443 DEBUG(pr_info("Invalid minor %d\n", dev));
444 return -ENODEV;
445 }
446 port = &ports[dev];
447 /* Allow open this device twice (assuming one reader and one writer) */
448 if (port->busy == 2) {
449 DEBUG(pr_info("syncser%d is busy\n", dev));
450 return -EBUSY;
451 }
452
453 mutex_lock(&sync_serial_mutex);
454
455 /* Clear any stale date left in the flip buffer */
456 port->readp = port->writep = port->flip;
457 port->in_buffer_len = 0;
458 port->read_ts_idx = 0;
459 port->write_ts_idx = 0;
460
461 if (port->init_irqs != no_irq_setup) {
462 /* Init only on first call. */
463 port->busy++;
464 mutex_unlock(&sync_serial_mutex);
465 return 0;
466 }
467 if (port->use_dma) {
468 #ifdef SYNC_SER_DMA
469 const char *tmp;
470 DEBUG(pr_info("Using DMA for syncser%d\n", dev));
471
472 tmp = dev == 0 ? "syncser0 tx" : "syncser1 tx";
473 if (request_irq(port->dma_out_intr_vect, tr_interrupt, 0,
474 tmp, port)) {
475 pr_err("Can't alloc syncser%d TX IRQ", dev);
476 ret = -EBUSY;
477 goto unlock_and_exit;
478 }
479 if (artpec_request_dma(port->dma_out_nbr, tmp,
480 DMA_VERBOSE_ON_ERROR, 0, port->req_dma)) {
481 free_irq(port->dma_out_intr_vect, port);
482 pr_err("Can't alloc syncser%d TX DMA", dev);
483 ret = -EBUSY;
484 goto unlock_and_exit;
485 }
486 tmp = dev == 0 ? "syncser0 rx" : "syncser1 rx";
487 if (request_irq(port->dma_in_intr_vect, rx_interrupt, 0,
488 tmp, port)) {
489 artpec_free_dma(port->dma_out_nbr);
490 free_irq(port->dma_out_intr_vect, port);
491 pr_err("Can't alloc syncser%d RX IRQ", dev);
492 ret = -EBUSY;
493 goto unlock_and_exit;
494 }
495 if (artpec_request_dma(port->dma_in_nbr, tmp,
496 DMA_VERBOSE_ON_ERROR, 0, port->req_dma)) {
497 artpec_free_dma(port->dma_out_nbr);
498 free_irq(port->dma_out_intr_vect, port);
499 free_irq(port->dma_in_intr_vect, port);
500 pr_err("Can't alloc syncser%d RX DMA", dev);
501 ret = -EBUSY;
502 goto unlock_and_exit;
503 }
504 /* Enable DMAs */
505 REG_WR(dma, port->regi_dmain, rw_cfg, cfg);
506 REG_WR(dma, port->regi_dmaout, rw_cfg, cfg);
507 /* Enable DMA IRQs */
508 REG_WR(dma, port->regi_dmain, rw_intr_mask, intr_mask);
509 REG_WR(dma, port->regi_dmaout, rw_intr_mask, intr_mask);
510 /* Set up wordsize = 1 for DMAs. */
511 DMA_WR_CMD(port->regi_dmain, regk_dma_set_w_size1);
512 DMA_WR_CMD(port->regi_dmaout, regk_dma_set_w_size1);
513
514 start_dma_in(port);
515 port->init_irqs = dma_irq_setup;
516 #endif
517 } else { /* !port->use_dma */
518 #ifdef SYNC_SER_MANUAL
519 const char *tmp = dev == 0 ? "syncser0 manual irq" :
520 "syncser1 manual irq";
521 if (request_irq(port->syncser_intr_vect, manual_interrupt,
522 0, tmp, port)) {
523 pr_err("Can't alloc syncser%d manual irq",
524 dev);
525 ret = -EBUSY;
526 goto unlock_and_exit;
527 }
528 port->init_irqs = manual_irq_setup;
529 #else
530 panic("sync_serial: Manual mode not supported\n");
531 #endif /* SYNC_SER_MANUAL */
532 }
533 port->busy++;
534 ret = 0;
535
536 unlock_and_exit:
537 mutex_unlock(&sync_serial_mutex);
538 return ret;
539 }
540
sync_serial_release(struct inode * inode,struct file * file)541 static int sync_serial_release(struct inode *inode, struct file *file)
542 {
543 int dev = iminor(inode);
544 struct sync_port *port;
545
546 if (dev < 0 || dev >= NBR_PORTS || !ports[dev].enabled) {
547 DEBUG(pr_info("Invalid minor %d\n", dev));
548 return -ENODEV;
549 }
550 port = &ports[dev];
551 if (port->busy)
552 port->busy--;
553 if (!port->busy)
554 /* XXX */;
555 return 0;
556 }
557
sync_serial_poll(struct file * file,poll_table * wait)558 static unsigned int sync_serial_poll(struct file *file, poll_table *wait)
559 {
560 int dev = iminor(file_inode(file));
561 unsigned int mask = 0;
562 struct sync_port *port;
563 DEBUGPOLL(
564 static unsigned int prev_mask;
565 );
566
567 port = &ports[dev];
568
569 if (!port->started)
570 sync_serial_start_port(port);
571
572 poll_wait(file, &port->out_wait_q, wait);
573 poll_wait(file, &port->in_wait_q, wait);
574
575 /* No active transfer, descriptors are available */
576 if (port->output && !port->tr_running)
577 mask |= POLLOUT | POLLWRNORM;
578
579 /* Descriptor and buffer space available. */
580 if (port->output &&
581 port->active_tr_descr != port->catch_tr_descr &&
582 port->out_buf_count < OUT_BUFFER_SIZE)
583 mask |= POLLOUT | POLLWRNORM;
584
585 /* At least an inbufchunk of data */
586 if (port->input && sync_data_avail(port) >= port->inbufchunk)
587 mask |= POLLIN | POLLRDNORM;
588
589 DEBUGPOLL(
590 if (mask != prev_mask)
591 pr_info("sync_serial_poll: mask 0x%08X %s %s\n",
592 mask,
593 mask & POLLOUT ? "POLLOUT" : "",
594 mask & POLLIN ? "POLLIN" : "");
595 prev_mask = mask;
596 );
597 return mask;
598 }
599
__sync_serial_read(struct file * file,char __user * buf,size_t count,loff_t * ppos,struct timespec * ts)600 static ssize_t __sync_serial_read(struct file *file,
601 char __user *buf,
602 size_t count,
603 loff_t *ppos,
604 struct timespec *ts)
605 {
606 unsigned long flags;
607 int dev = MINOR(file_inode(file)->i_rdev);
608 int avail;
609 struct sync_port *port;
610 unsigned char *start;
611 unsigned char *end;
612
613 if (dev < 0 || dev >= NBR_PORTS || !ports[dev].enabled) {
614 DEBUG(pr_info("Invalid minor %d\n", dev));
615 return -ENODEV;
616 }
617 port = &ports[dev];
618
619 if (!port->started)
620 sync_serial_start_port(port);
621
622 /* Calculate number of available bytes */
623 /* Save pointers to avoid that they are modified by interrupt */
624 spin_lock_irqsave(&port->lock, flags);
625 start = port->readp;
626 end = port->writep;
627 spin_unlock_irqrestore(&port->lock, flags);
628
629 while ((start == end) && !port->in_buffer_len) {
630 if (file->f_flags & O_NONBLOCK)
631 return -EAGAIN;
632
633 wait_event_interruptible(port->in_wait_q,
634 !(start == end && !port->full));
635
636 if (signal_pending(current))
637 return -EINTR;
638
639 spin_lock_irqsave(&port->lock, flags);
640 start = port->readp;
641 end = port->writep;
642 spin_unlock_irqrestore(&port->lock, flags);
643 }
644
645 DEBUGREAD(pr_info("R%d c %d ri %u wi %u /%u\n",
646 dev, count,
647 start - port->flip, end - port->flip,
648 port->in_buffer_size));
649
650 /* Lazy read, never return wrapped data. */
651 if (end > start)
652 avail = end - start;
653 else
654 avail = port->flip + port->in_buffer_size - start;
655
656 count = count > avail ? avail : count;
657 if (copy_to_user(buf, start, count))
658 return -EFAULT;
659
660 /* If timestamp requested, find timestamp of first returned byte
661 * and copy it.
662 * N.B: Applications that request timstamps MUST read data in
663 * chunks that are multiples of IN_DESCR_SIZE.
664 * Otherwise the timestamps will not be aligned to the data read.
665 */
666 if (ts != NULL) {
667 int idx = port->read_ts_idx;
668 memcpy(ts, &port->timestamp[idx], sizeof(struct timespec));
669 port->read_ts_idx += count / IN_DESCR_SIZE;
670 if (port->read_ts_idx >= NBR_IN_DESCR)
671 port->read_ts_idx = 0;
672 }
673
674 spin_lock_irqsave(&port->lock, flags);
675 port->readp += count;
676 /* Check for wrap */
677 if (port->readp >= port->flip + port->in_buffer_size)
678 port->readp = port->flip;
679 port->in_buffer_len -= count;
680 port->full = 0;
681 spin_unlock_irqrestore(&port->lock, flags);
682
683 DEBUGREAD(pr_info("r %d\n", count));
684
685 return count;
686 }
687
sync_serial_input(struct file * file,unsigned long arg)688 static ssize_t sync_serial_input(struct file *file, unsigned long arg)
689 {
690 struct ssp_request req;
691 int count;
692 int ret;
693
694 /* Copy the request structure from user-mode. */
695 ret = copy_from_user(&req, (struct ssp_request __user *)arg,
696 sizeof(struct ssp_request));
697
698 if (ret) {
699 DEBUG(pr_info("sync_serial_input copy from user failed\n"));
700 return -EFAULT;
701 }
702
703 /* To get the timestamps aligned, make sure that 'len'
704 * is a multiple of IN_DESCR_SIZE.
705 */
706 if ((req.len % IN_DESCR_SIZE) != 0) {
707 DEBUG(pr_info("sync_serial: req.len %x, IN_DESCR_SIZE %x\n",
708 req.len, IN_DESCR_SIZE));
709 return -EFAULT;
710 }
711
712 /* Do the actual read. */
713 /* Note that req.buf is actually a pointer to user space. */
714 count = __sync_serial_read(file, req.buf, req.len,
715 NULL, &req.ts);
716
717 if (count < 0) {
718 DEBUG(pr_info("sync_serial_input read failed\n"));
719 return count;
720 }
721
722 /* Copy the request back to user-mode. */
723 ret = copy_to_user((struct ssp_request __user *)arg, &req,
724 sizeof(struct ssp_request));
725
726 if (ret) {
727 DEBUG(pr_info("syncser input copy2user failed\n"));
728 return -EFAULT;
729 }
730
731 /* Return the number of bytes read. */
732 return count;
733 }
734
735
sync_serial_ioctl_unlocked(struct file * file,unsigned int cmd,unsigned long arg)736 static int sync_serial_ioctl_unlocked(struct file *file,
737 unsigned int cmd, unsigned long arg)
738 {
739 int return_val = 0;
740 int dma_w_size = regk_dma_set_w_size1;
741 int dev = iminor(file_inode(file));
742 struct sync_port *port;
743 reg_sser_rw_tr_cfg tr_cfg;
744 reg_sser_rw_rec_cfg rec_cfg;
745 reg_sser_rw_frm_cfg frm_cfg;
746 reg_sser_rw_cfg gen_cfg;
747 reg_sser_rw_intr_mask intr_mask;
748
749 if (dev < 0 || dev >= NBR_PORTS || !ports[dev].enabled) {
750 DEBUG(pr_info("Invalid minor %d\n", dev));
751 return -1;
752 }
753
754 if (cmd == SSP_INPUT)
755 return sync_serial_input(file, arg);
756
757 port = &ports[dev];
758 spin_lock_irq(&port->lock);
759
760 tr_cfg = REG_RD(sser, port->regi_sser, rw_tr_cfg);
761 rec_cfg = REG_RD(sser, port->regi_sser, rw_rec_cfg);
762 frm_cfg = REG_RD(sser, port->regi_sser, rw_frm_cfg);
763 gen_cfg = REG_RD(sser, port->regi_sser, rw_cfg);
764 intr_mask = REG_RD(sser, port->regi_sser, rw_intr_mask);
765
766 switch (cmd) {
767 case SSP_SPEED:
768 if (GET_SPEED(arg) == CODEC) {
769 unsigned int freq;
770
771 gen_cfg.base_freq = regk_sser_f32;
772
773 /* Clock divider will internally be
774 * gen_cfg.clk_div + 1.
775 */
776
777 freq = GET_FREQ(arg);
778 switch (freq) {
779 case FREQ_32kHz:
780 case FREQ_64kHz:
781 case FREQ_128kHz:
782 case FREQ_256kHz:
783 gen_cfg.clk_div = 125 *
784 (1 << (freq - FREQ_256kHz)) - 1;
785 break;
786 case FREQ_512kHz:
787 gen_cfg.clk_div = 62;
788 break;
789 case FREQ_1MHz:
790 case FREQ_2MHz:
791 case FREQ_4MHz:
792 gen_cfg.clk_div = 8 * (1 << freq) - 1;
793 break;
794 }
795 } else if (GET_SPEED(arg) == CODEC_f32768) {
796 gen_cfg.base_freq = regk_sser_f32_768;
797 switch (GET_FREQ(arg)) {
798 case FREQ_4096kHz:
799 gen_cfg.clk_div = 7;
800 break;
801 default:
802 spin_unlock_irq(&port->lock);
803 return -EINVAL;
804 }
805 } else {
806 gen_cfg.base_freq = regk_sser_f29_493;
807 switch (GET_SPEED(arg)) {
808 case SSP150:
809 gen_cfg.clk_div = 29493000 / (150 * 8) - 1;
810 break;
811 case SSP300:
812 gen_cfg.clk_div = 29493000 / (300 * 8) - 1;
813 break;
814 case SSP600:
815 gen_cfg.clk_div = 29493000 / (600 * 8) - 1;
816 break;
817 case SSP1200:
818 gen_cfg.clk_div = 29493000 / (1200 * 8) - 1;
819 break;
820 case SSP2400:
821 gen_cfg.clk_div = 29493000 / (2400 * 8) - 1;
822 break;
823 case SSP4800:
824 gen_cfg.clk_div = 29493000 / (4800 * 8) - 1;
825 break;
826 case SSP9600:
827 gen_cfg.clk_div = 29493000 / (9600 * 8) - 1;
828 break;
829 case SSP19200:
830 gen_cfg.clk_div = 29493000 / (19200 * 8) - 1;
831 break;
832 case SSP28800:
833 gen_cfg.clk_div = 29493000 / (28800 * 8) - 1;
834 break;
835 case SSP57600:
836 gen_cfg.clk_div = 29493000 / (57600 * 8) - 1;
837 break;
838 case SSP115200:
839 gen_cfg.clk_div = 29493000 / (115200 * 8) - 1;
840 break;
841 case SSP230400:
842 gen_cfg.clk_div = 29493000 / (230400 * 8) - 1;
843 break;
844 case SSP460800:
845 gen_cfg.clk_div = 29493000 / (460800 * 8) - 1;
846 break;
847 case SSP921600:
848 gen_cfg.clk_div = 29493000 / (921600 * 8) - 1;
849 break;
850 case SSP3125000:
851 gen_cfg.base_freq = regk_sser_f100;
852 gen_cfg.clk_div = 100000000 / (3125000 * 8) - 1;
853 break;
854
855 }
856 }
857 frm_cfg.wordrate = GET_WORD_RATE(arg);
858
859 break;
860 case SSP_MODE:
861 switch (arg) {
862 case MASTER_OUTPUT:
863 port->output = 1;
864 port->input = 0;
865 frm_cfg.out_on = regk_sser_tr;
866 frm_cfg.frame_pin_dir = regk_sser_out;
867 gen_cfg.clk_dir = regk_sser_out;
868 break;
869 case SLAVE_OUTPUT:
870 port->output = 1;
871 port->input = 0;
872 frm_cfg.frame_pin_dir = regk_sser_in;
873 gen_cfg.clk_dir = regk_sser_in;
874 break;
875 case MASTER_INPUT:
876 port->output = 0;
877 port->input = 1;
878 frm_cfg.frame_pin_dir = regk_sser_out;
879 frm_cfg.out_on = regk_sser_intern_tb;
880 gen_cfg.clk_dir = regk_sser_out;
881 break;
882 case SLAVE_INPUT:
883 port->output = 0;
884 port->input = 1;
885 frm_cfg.frame_pin_dir = regk_sser_in;
886 gen_cfg.clk_dir = regk_sser_in;
887 break;
888 case MASTER_BIDIR:
889 port->output = 1;
890 port->input = 1;
891 frm_cfg.frame_pin_dir = regk_sser_out;
892 frm_cfg.out_on = regk_sser_intern_tb;
893 gen_cfg.clk_dir = regk_sser_out;
894 break;
895 case SLAVE_BIDIR:
896 port->output = 1;
897 port->input = 1;
898 frm_cfg.frame_pin_dir = regk_sser_in;
899 gen_cfg.clk_dir = regk_sser_in;
900 break;
901 default:
902 spin_unlock_irq(&port->lock);
903 return -EINVAL;
904 }
905 if (!port->use_dma || arg == MASTER_OUTPUT ||
906 arg == SLAVE_OUTPUT)
907 intr_mask.rdav = regk_sser_yes;
908 break;
909 case SSP_FRAME_SYNC:
910 if (arg & NORMAL_SYNC) {
911 frm_cfg.rec_delay = 1;
912 frm_cfg.tr_delay = 1;
913 } else if (arg & EARLY_SYNC)
914 frm_cfg.rec_delay = frm_cfg.tr_delay = 0;
915 else if (arg & LATE_SYNC) {
916 frm_cfg.tr_delay = 2;
917 frm_cfg.rec_delay = 2;
918 } else if (arg & SECOND_WORD_SYNC) {
919 frm_cfg.rec_delay = 7;
920 frm_cfg.tr_delay = 1;
921 }
922
923 tr_cfg.bulk_wspace = frm_cfg.tr_delay;
924 frm_cfg.early_wend = regk_sser_yes;
925 if (arg & BIT_SYNC)
926 frm_cfg.type = regk_sser_edge;
927 else if (arg & WORD_SYNC)
928 frm_cfg.type = regk_sser_level;
929 else if (arg & EXTENDED_SYNC)
930 frm_cfg.early_wend = regk_sser_no;
931
932 if (arg & SYNC_ON)
933 frm_cfg.frame_pin_use = regk_sser_frm;
934 else if (arg & SYNC_OFF)
935 frm_cfg.frame_pin_use = regk_sser_gio0;
936
937 dma_w_size = regk_dma_set_w_size2;
938 if (arg & WORD_SIZE_8) {
939 rec_cfg.sample_size = tr_cfg.sample_size = 7;
940 dma_w_size = regk_dma_set_w_size1;
941 } else if (arg & WORD_SIZE_12)
942 rec_cfg.sample_size = tr_cfg.sample_size = 11;
943 else if (arg & WORD_SIZE_16)
944 rec_cfg.sample_size = tr_cfg.sample_size = 15;
945 else if (arg & WORD_SIZE_24)
946 rec_cfg.sample_size = tr_cfg.sample_size = 23;
947 else if (arg & WORD_SIZE_32)
948 rec_cfg.sample_size = tr_cfg.sample_size = 31;
949
950 if (arg & BIT_ORDER_MSB)
951 rec_cfg.sh_dir = tr_cfg.sh_dir = regk_sser_msbfirst;
952 else if (arg & BIT_ORDER_LSB)
953 rec_cfg.sh_dir = tr_cfg.sh_dir = regk_sser_lsbfirst;
954
955 if (arg & FLOW_CONTROL_ENABLE) {
956 frm_cfg.status_pin_use = regk_sser_frm;
957 rec_cfg.fifo_thr = regk_sser_thr16;
958 } else if (arg & FLOW_CONTROL_DISABLE) {
959 frm_cfg.status_pin_use = regk_sser_gio0;
960 rec_cfg.fifo_thr = regk_sser_inf;
961 }
962
963 if (arg & CLOCK_NOT_GATED)
964 gen_cfg.gate_clk = regk_sser_no;
965 else if (arg & CLOCK_GATED)
966 gen_cfg.gate_clk = regk_sser_yes;
967
968 break;
969 case SSP_IPOLARITY:
970 /* NOTE!! negedge is considered NORMAL */
971 if (arg & CLOCK_NORMAL)
972 rec_cfg.clk_pol = regk_sser_neg;
973 else if (arg & CLOCK_INVERT)
974 rec_cfg.clk_pol = regk_sser_pos;
975
976 if (arg & FRAME_NORMAL)
977 frm_cfg.level = regk_sser_pos_hi;
978 else if (arg & FRAME_INVERT)
979 frm_cfg.level = regk_sser_neg_lo;
980
981 if (arg & STATUS_NORMAL)
982 gen_cfg.hold_pol = regk_sser_pos;
983 else if (arg & STATUS_INVERT)
984 gen_cfg.hold_pol = regk_sser_neg;
985 break;
986 case SSP_OPOLARITY:
987 if (arg & CLOCK_NORMAL)
988 gen_cfg.out_clk_pol = regk_sser_pos;
989 else if (arg & CLOCK_INVERT)
990 gen_cfg.out_clk_pol = regk_sser_neg;
991
992 if (arg & FRAME_NORMAL)
993 frm_cfg.level = regk_sser_pos_hi;
994 else if (arg & FRAME_INVERT)
995 frm_cfg.level = regk_sser_neg_lo;
996
997 if (arg & STATUS_NORMAL)
998 gen_cfg.hold_pol = regk_sser_pos;
999 else if (arg & STATUS_INVERT)
1000 gen_cfg.hold_pol = regk_sser_neg;
1001 break;
1002 case SSP_SPI:
1003 rec_cfg.fifo_thr = regk_sser_inf;
1004 rec_cfg.sh_dir = tr_cfg.sh_dir = regk_sser_msbfirst;
1005 rec_cfg.sample_size = tr_cfg.sample_size = 7;
1006 frm_cfg.frame_pin_use = regk_sser_frm;
1007 frm_cfg.type = regk_sser_level;
1008 frm_cfg.tr_delay = 1;
1009 frm_cfg.level = regk_sser_neg_lo;
1010 if (arg & SPI_SLAVE) {
1011 rec_cfg.clk_pol = regk_sser_neg;
1012 gen_cfg.clk_dir = regk_sser_in;
1013 port->input = 1;
1014 port->output = 0;
1015 } else {
1016 gen_cfg.out_clk_pol = regk_sser_pos;
1017 port->input = 0;
1018 port->output = 1;
1019 gen_cfg.clk_dir = regk_sser_out;
1020 }
1021 break;
1022 case SSP_INBUFCHUNK:
1023 break;
1024 default:
1025 return_val = -1;
1026 }
1027
1028
1029 if (port->started) {
1030 rec_cfg.rec_en = port->input;
1031 gen_cfg.en = (port->output | port->input);
1032 }
1033
1034 REG_WR(sser, port->regi_sser, rw_tr_cfg, tr_cfg);
1035 REG_WR(sser, port->regi_sser, rw_rec_cfg, rec_cfg);
1036 REG_WR(sser, port->regi_sser, rw_frm_cfg, frm_cfg);
1037 REG_WR(sser, port->regi_sser, rw_intr_mask, intr_mask);
1038 REG_WR(sser, port->regi_sser, rw_cfg, gen_cfg);
1039
1040
1041 if (cmd == SSP_FRAME_SYNC && (arg & (WORD_SIZE_8 | WORD_SIZE_12 |
1042 WORD_SIZE_16 | WORD_SIZE_24 | WORD_SIZE_32))) {
1043 int en = gen_cfg.en;
1044 gen_cfg.en = 0;
1045 REG_WR(sser, port->regi_sser, rw_cfg, gen_cfg);
1046 /* ##### Should DMA be stoped before we change dma size? */
1047 DMA_WR_CMD(port->regi_dmain, dma_w_size);
1048 DMA_WR_CMD(port->regi_dmaout, dma_w_size);
1049 gen_cfg.en = en;
1050 REG_WR(sser, port->regi_sser, rw_cfg, gen_cfg);
1051 }
1052
1053 spin_unlock_irq(&port->lock);
1054 return return_val;
1055 }
1056
sync_serial_ioctl(struct file * file,unsigned int cmd,unsigned long arg)1057 static long sync_serial_ioctl(struct file *file,
1058 unsigned int cmd, unsigned long arg)
1059 {
1060 long ret;
1061
1062 mutex_lock(&sync_serial_mutex);
1063 ret = sync_serial_ioctl_unlocked(file, cmd, arg);
1064 mutex_unlock(&sync_serial_mutex);
1065
1066 return ret;
1067 }
1068
1069 /* NOTE: sync_serial_write does not support concurrency */
sync_serial_write(struct file * file,const char __user * buf,size_t count,loff_t * ppos)1070 static ssize_t sync_serial_write(struct file *file, const char __user *buf,
1071 size_t count, loff_t *ppos)
1072 {
1073 int dev = iminor(file_inode(file));
1074 DECLARE_WAITQUEUE(wait, current);
1075 struct sync_port *port;
1076 int trunc_count;
1077 unsigned long flags;
1078 int bytes_free;
1079 int out_buf_count;
1080
1081 unsigned char *rd_ptr; /* First allocated byte in the buffer */
1082 unsigned char *wr_ptr; /* First free byte in the buffer */
1083 unsigned char *buf_stop_ptr; /* Last byte + 1 */
1084
1085 if (dev < 0 || dev >= NBR_PORTS || !ports[dev].enabled) {
1086 DEBUG(pr_info("Invalid minor %d\n", dev));
1087 return -ENODEV;
1088 }
1089 port = &ports[dev];
1090
1091 /* |<- OUT_BUFFER_SIZE ->|
1092 * |<- out_buf_count ->|
1093 * |<- trunc_count ->| ...->|
1094 * ______________________________________________________
1095 * | free | data | free |
1096 * |_________|___________________|________________________|
1097 * ^ rd_ptr ^ wr_ptr
1098 */
1099 DEBUGWRITE(pr_info("W d%d c %u a: %p c: %p\n",
1100 port->port_nbr, count, port->active_tr_descr,
1101 port->catch_tr_descr));
1102
1103 /* Read variables that may be updated by interrupts */
1104 spin_lock_irqsave(&port->lock, flags);
1105 rd_ptr = port->out_rd_ptr;
1106 out_buf_count = port->out_buf_count;
1107 spin_unlock_irqrestore(&port->lock, flags);
1108
1109 /* Check if resources are available */
1110 if (port->tr_running &&
1111 ((port->use_dma && port->active_tr_descr == port->catch_tr_descr) ||
1112 out_buf_count >= OUT_BUFFER_SIZE)) {
1113 DEBUGWRITE(pr_info("sser%d full\n", dev));
1114 return -EAGAIN;
1115 }
1116
1117 buf_stop_ptr = port->out_buffer + OUT_BUFFER_SIZE;
1118
1119 /* Determine pointer to the first free byte, before copying. */
1120 wr_ptr = rd_ptr + out_buf_count;
1121 if (wr_ptr >= buf_stop_ptr)
1122 wr_ptr -= OUT_BUFFER_SIZE;
1123
1124 /* If we wrap the ring buffer, let the user space program handle it by
1125 * truncating the data. This could be more elegant, small buffer
1126 * fragments may occur.
1127 */
1128 bytes_free = OUT_BUFFER_SIZE - out_buf_count;
1129 if (wr_ptr + bytes_free > buf_stop_ptr)
1130 bytes_free = buf_stop_ptr - wr_ptr;
1131 trunc_count = (count < bytes_free) ? count : bytes_free;
1132
1133 if (copy_from_user(wr_ptr, buf, trunc_count))
1134 return -EFAULT;
1135
1136 DEBUGOUTBUF(pr_info("%-4d + %-4d = %-4d %p %p %p\n",
1137 out_buf_count, trunc_count,
1138 port->out_buf_count, port->out_buffer,
1139 wr_ptr, buf_stop_ptr));
1140
1141 /* Make sure transmitter/receiver is running */
1142 if (!port->started) {
1143 reg_sser_rw_cfg cfg = REG_RD(sser, port->regi_sser, rw_cfg);
1144 reg_sser_rw_rec_cfg rec_cfg =
1145 REG_RD(sser, port->regi_sser, rw_rec_cfg);
1146 cfg.en = regk_sser_yes;
1147 rec_cfg.rec_en = port->input;
1148 REG_WR(sser, port->regi_sser, rw_cfg, cfg);
1149 REG_WR(sser, port->regi_sser, rw_rec_cfg, rec_cfg);
1150 port->started = 1;
1151 }
1152
1153 /* Setup wait if blocking */
1154 if (!(file->f_flags & O_NONBLOCK)) {
1155 add_wait_queue(&port->out_wait_q, &wait);
1156 set_current_state(TASK_INTERRUPTIBLE);
1157 }
1158
1159 spin_lock_irqsave(&port->lock, flags);
1160 port->out_buf_count += trunc_count;
1161 if (port->use_dma) {
1162 #ifdef SYNC_SER_DMA
1163 start_dma_out(port, wr_ptr, trunc_count);
1164 #endif
1165 } else if (!port->tr_running) {
1166 #ifdef SYNC_SER_MANUAL
1167 reg_sser_rw_intr_mask intr_mask;
1168 intr_mask = REG_RD(sser, port->regi_sser, rw_intr_mask);
1169 /* Start sender by writing data */
1170 send_word(port);
1171 /* and enable transmitter ready IRQ */
1172 intr_mask.trdy = 1;
1173 REG_WR(sser, port->regi_sser, rw_intr_mask, intr_mask);
1174 #endif
1175 }
1176 spin_unlock_irqrestore(&port->lock, flags);
1177
1178 /* Exit if non blocking */
1179 if (file->f_flags & O_NONBLOCK) {
1180 DEBUGWRITE(pr_info("w d%d c %u %08x\n",
1181 port->port_nbr, trunc_count,
1182 REG_RD_INT(dma, port->regi_dmaout, r_intr)));
1183 return trunc_count;
1184 }
1185
1186 schedule();
1187 remove_wait_queue(&port->out_wait_q, &wait);
1188
1189 if (signal_pending(current))
1190 return -EINTR;
1191
1192 DEBUGWRITE(pr_info("w d%d c %u\n", port->port_nbr, trunc_count));
1193 return trunc_count;
1194 }
1195
sync_serial_read(struct file * file,char __user * buf,size_t count,loff_t * ppos)1196 static ssize_t sync_serial_read(struct file *file, char __user *buf,
1197 size_t count, loff_t *ppos)
1198 {
1199 return __sync_serial_read(file, buf, count, ppos, NULL);
1200 }
1201
1202 #ifdef SYNC_SER_MANUAL
send_word(struct sync_port * port)1203 static void send_word(struct sync_port *port)
1204 {
1205 reg_sser_rw_tr_cfg tr_cfg = REG_RD(sser, port->regi_sser, rw_tr_cfg);
1206 reg_sser_rw_tr_data tr_data = {0};
1207
1208 switch (tr_cfg.sample_size) {
1209 case 8:
1210 port->out_buf_count--;
1211 tr_data.data = *port->out_rd_ptr++;
1212 REG_WR(sser, port->regi_sser, rw_tr_data, tr_data);
1213 if (port->out_rd_ptr >= port->out_buffer + OUT_BUFFER_SIZE)
1214 port->out_rd_ptr = port->out_buffer;
1215 break;
1216 case 12:
1217 {
1218 int data = (*port->out_rd_ptr++) << 8;
1219 data |= *port->out_rd_ptr++;
1220 port->out_buf_count -= 2;
1221 tr_data.data = data;
1222 REG_WR(sser, port->regi_sser, rw_tr_data, tr_data);
1223 if (port->out_rd_ptr >= port->out_buffer + OUT_BUFFER_SIZE)
1224 port->out_rd_ptr = port->out_buffer;
1225 break;
1226 }
1227 case 16:
1228 port->out_buf_count -= 2;
1229 tr_data.data = *(unsigned short *)port->out_rd_ptr;
1230 REG_WR(sser, port->regi_sser, rw_tr_data, tr_data);
1231 port->out_rd_ptr += 2;
1232 if (port->out_rd_ptr >= port->out_buffer + OUT_BUFFER_SIZE)
1233 port->out_rd_ptr = port->out_buffer;
1234 break;
1235 case 24:
1236 port->out_buf_count -= 3;
1237 tr_data.data = *(unsigned short *)port->out_rd_ptr;
1238 REG_WR(sser, port->regi_sser, rw_tr_data, tr_data);
1239 port->out_rd_ptr += 2;
1240 tr_data.data = *port->out_rd_ptr++;
1241 REG_WR(sser, port->regi_sser, rw_tr_data, tr_data);
1242 if (port->out_rd_ptr >= port->out_buffer + OUT_BUFFER_SIZE)
1243 port->out_rd_ptr = port->out_buffer;
1244 break;
1245 case 32:
1246 port->out_buf_count -= 4;
1247 tr_data.data = *(unsigned short *)port->out_rd_ptr;
1248 REG_WR(sser, port->regi_sser, rw_tr_data, tr_data);
1249 port->out_rd_ptr += 2;
1250 tr_data.data = *(unsigned short *)port->out_rd_ptr;
1251 REG_WR(sser, port->regi_sser, rw_tr_data, tr_data);
1252 port->out_rd_ptr += 2;
1253 if (port->out_rd_ptr >= port->out_buffer + OUT_BUFFER_SIZE)
1254 port->out_rd_ptr = port->out_buffer;
1255 break;
1256 }
1257 }
1258 #endif
1259
1260 #ifdef SYNC_SER_DMA
start_dma_out(struct sync_port * port,const char * data,int count)1261 static void start_dma_out(struct sync_port *port, const char *data, int count)
1262 {
1263 port->active_tr_descr->buf = (char *)virt_to_phys((char *)data);
1264 port->active_tr_descr->after = port->active_tr_descr->buf + count;
1265 port->active_tr_descr->intr = 1;
1266
1267 port->active_tr_descr->eol = 1;
1268 port->prev_tr_descr->eol = 0;
1269
1270 DEBUGTRDMA(pr_info("Inserting eolr:%p eol@:%p\n",
1271 port->prev_tr_descr, port->active_tr_descr));
1272 port->prev_tr_descr = port->active_tr_descr;
1273 port->active_tr_descr = phys_to_virt((int)port->active_tr_descr->next);
1274
1275 if (!port->tr_running) {
1276 reg_sser_rw_tr_cfg tr_cfg = REG_RD(sser, port->regi_sser,
1277 rw_tr_cfg);
1278
1279 port->out_context.next = NULL;
1280 port->out_context.saved_data =
1281 (dma_descr_data *)virt_to_phys(port->prev_tr_descr);
1282 port->out_context.saved_data_buf = port->prev_tr_descr->buf;
1283
1284 DMA_START_CONTEXT(port->regi_dmaout,
1285 virt_to_phys((char *)&port->out_context));
1286
1287 tr_cfg.tr_en = regk_sser_yes;
1288 REG_WR(sser, port->regi_sser, rw_tr_cfg, tr_cfg);
1289 DEBUGTRDMA(pr_info("dma s\n"););
1290 } else {
1291 DMA_CONTINUE_DATA(port->regi_dmaout);
1292 DEBUGTRDMA(pr_info("dma c\n"););
1293 }
1294
1295 port->tr_running = 1;
1296 }
1297
start_dma_in(struct sync_port * port)1298 static void start_dma_in(struct sync_port *port)
1299 {
1300 int i;
1301 char *buf;
1302 unsigned long flags;
1303 spin_lock_irqsave(&port->lock, flags);
1304 port->writep = port->flip;
1305 spin_unlock_irqrestore(&port->lock, flags);
1306
1307 buf = (char *)virt_to_phys(port->in_buffer);
1308 for (i = 0; i < NBR_IN_DESCR; i++) {
1309 port->in_descr[i].buf = buf;
1310 port->in_descr[i].after = buf + port->inbufchunk;
1311 port->in_descr[i].intr = 1;
1312 port->in_descr[i].next =
1313 (dma_descr_data *)virt_to_phys(&port->in_descr[i+1]);
1314 port->in_descr[i].buf = buf;
1315 buf += port->inbufchunk;
1316 }
1317 /* Link the last descriptor to the first */
1318 port->in_descr[i-1].next =
1319 (dma_descr_data *)virt_to_phys(&port->in_descr[0]);
1320 port->in_descr[i-1].eol = regk_sser_yes;
1321 port->next_rx_desc = &port->in_descr[0];
1322 port->prev_rx_desc = &port->in_descr[NBR_IN_DESCR - 1];
1323 port->in_context.saved_data =
1324 (dma_descr_data *)virt_to_phys(&port->in_descr[0]);
1325 port->in_context.saved_data_buf = port->in_descr[0].buf;
1326 DMA_START_CONTEXT(port->regi_dmain, virt_to_phys(&port->in_context));
1327 }
1328
tr_interrupt(int irq,void * dev_id)1329 static irqreturn_t tr_interrupt(int irq, void *dev_id)
1330 {
1331 reg_dma_r_masked_intr masked;
1332 reg_dma_rw_ack_intr ack_intr = { .data = regk_dma_yes };
1333 reg_dma_rw_stat stat;
1334 int i;
1335 int found = 0;
1336 int stop_sser = 0;
1337
1338 for (i = 0; i < NBR_PORTS; i++) {
1339 struct sync_port *port = &ports[i];
1340 if (!port->enabled || !port->use_dma)
1341 continue;
1342
1343 /* IRQ active for the port? */
1344 masked = REG_RD(dma, port->regi_dmaout, r_masked_intr);
1345 if (!masked.data)
1346 continue;
1347
1348 found = 1;
1349
1350 /* Check if we should stop the DMA transfer */
1351 stat = REG_RD(dma, port->regi_dmaout, rw_stat);
1352 if (stat.list_state == regk_dma_data_at_eol)
1353 stop_sser = 1;
1354
1355 /* Clear IRQ */
1356 REG_WR(dma, port->regi_dmaout, rw_ack_intr, ack_intr);
1357
1358 if (!stop_sser) {
1359 /* The DMA has completed a descriptor, EOL was not
1360 * encountered, so step relevant descriptor and
1361 * datapointers forward. */
1362 int sent;
1363 sent = port->catch_tr_descr->after -
1364 port->catch_tr_descr->buf;
1365 DEBUGTXINT(pr_info("%-4d - %-4d = %-4d\t"
1366 "in descr %p (ac: %p)\n",
1367 port->out_buf_count, sent,
1368 port->out_buf_count - sent,
1369 port->catch_tr_descr,
1370 port->active_tr_descr););
1371 port->out_buf_count -= sent;
1372 port->catch_tr_descr =
1373 phys_to_virt((int) port->catch_tr_descr->next);
1374 port->out_rd_ptr =
1375 phys_to_virt((int) port->catch_tr_descr->buf);
1376 } else {
1377 reg_sser_rw_tr_cfg tr_cfg;
1378 int j, sent;
1379 /* EOL handler.
1380 * Note that if an EOL was encountered during the irq
1381 * locked section of sync_ser_write the DMA will be
1382 * restarted and the eol flag will be cleared.
1383 * The remaining descriptors will be traversed by
1384 * the descriptor interrupts as usual.
1385 */
1386 j = 0;
1387 while (!port->catch_tr_descr->eol) {
1388 sent = port->catch_tr_descr->after -
1389 port->catch_tr_descr->buf;
1390 DEBUGOUTBUF(pr_info(
1391 "traversing descr %p -%d (%d)\n",
1392 port->catch_tr_descr,
1393 sent,
1394 port->out_buf_count));
1395 port->out_buf_count -= sent;
1396 port->catch_tr_descr = phys_to_virt(
1397 (int)port->catch_tr_descr->next);
1398 j++;
1399 if (j >= NBR_OUT_DESCR) {
1400 /* TODO: Reset and recover */
1401 panic("sync_serial: missing eol");
1402 }
1403 }
1404 sent = port->catch_tr_descr->after -
1405 port->catch_tr_descr->buf;
1406 DEBUGOUTBUF(pr_info("eol at descr %p -%d (%d)\n",
1407 port->catch_tr_descr,
1408 sent,
1409 port->out_buf_count));
1410
1411 port->out_buf_count -= sent;
1412
1413 /* Update read pointer to first free byte, we
1414 * may already be writing data there. */
1415 port->out_rd_ptr =
1416 phys_to_virt((int) port->catch_tr_descr->after);
1417 if (port->out_rd_ptr > port->out_buffer +
1418 OUT_BUFFER_SIZE)
1419 port->out_rd_ptr = port->out_buffer;
1420
1421 tr_cfg = REG_RD(sser, port->regi_sser, rw_tr_cfg);
1422 DEBUGTXINT(pr_info(
1423 "tr_int DMA stop %d, set catch @ %p\n",
1424 port->out_buf_count,
1425 port->active_tr_descr));
1426 if (port->out_buf_count != 0)
1427 pr_err("sync_ser: buf not empty after eol\n");
1428 port->catch_tr_descr = port->active_tr_descr;
1429 port->tr_running = 0;
1430 tr_cfg.tr_en = regk_sser_no;
1431 REG_WR(sser, port->regi_sser, rw_tr_cfg, tr_cfg);
1432 }
1433 /* wake up the waiting process */
1434 wake_up_interruptible(&port->out_wait_q);
1435 }
1436 return IRQ_RETVAL(found);
1437 } /* tr_interrupt */
1438
1439
handle_rx_packet(struct sync_port * port)1440 static inline void handle_rx_packet(struct sync_port *port)
1441 {
1442 int idx;
1443 reg_dma_rw_ack_intr ack_intr = { .data = regk_dma_yes };
1444 unsigned long flags;
1445
1446 DEBUGRXINT(pr_info("!"));
1447 spin_lock_irqsave(&port->lock, flags);
1448
1449 /* If we overrun the user experience is crap regardless if we
1450 * drop new or old data. Its much easier to get it right when
1451 * dropping new data so lets do that.
1452 */
1453 if ((port->writep + port->inbufchunk <=
1454 port->flip + port->in_buffer_size) &&
1455 (port->in_buffer_len + port->inbufchunk < IN_BUFFER_SIZE)) {
1456 memcpy(port->writep,
1457 phys_to_virt((unsigned)port->next_rx_desc->buf),
1458 port->inbufchunk);
1459 port->writep += port->inbufchunk;
1460 if (port->writep >= port->flip + port->in_buffer_size)
1461 port->writep = port->flip;
1462
1463 /* Timestamp the new data chunk. */
1464 if (port->write_ts_idx == NBR_IN_DESCR)
1465 port->write_ts_idx = 0;
1466 idx = port->write_ts_idx++;
1467 ktime_get_ts(&port->timestamp[idx]);
1468 port->in_buffer_len += port->inbufchunk;
1469 }
1470 spin_unlock_irqrestore(&port->lock, flags);
1471
1472 port->next_rx_desc->eol = 1;
1473 port->prev_rx_desc->eol = 0;
1474 /* Cache bug workaround */
1475 flush_dma_descr(port->prev_rx_desc, 0);
1476 port->prev_rx_desc = port->next_rx_desc;
1477 port->next_rx_desc = phys_to_virt((unsigned)port->next_rx_desc->next);
1478 /* Cache bug workaround */
1479 flush_dma_descr(port->prev_rx_desc, 1);
1480 /* wake up the waiting process */
1481 wake_up_interruptible(&port->in_wait_q);
1482 DMA_CONTINUE(port->regi_dmain);
1483 REG_WR(dma, port->regi_dmain, rw_ack_intr, ack_intr);
1484
1485 }
1486
rx_interrupt(int irq,void * dev_id)1487 static irqreturn_t rx_interrupt(int irq, void *dev_id)
1488 {
1489 reg_dma_r_masked_intr masked;
1490
1491 int i;
1492 int found = 0;
1493
1494 DEBUG(pr_info("rx_interrupt\n"));
1495
1496 for (i = 0; i < NBR_PORTS; i++) {
1497 struct sync_port *port = &ports[i];
1498
1499 if (!port->enabled || !port->use_dma)
1500 continue;
1501
1502 masked = REG_RD(dma, port->regi_dmain, r_masked_intr);
1503
1504 if (!masked.data)
1505 continue;
1506
1507 /* Descriptor interrupt */
1508 found = 1;
1509 while (REG_RD(dma, port->regi_dmain, rw_data) !=
1510 virt_to_phys(port->next_rx_desc))
1511 handle_rx_packet(port);
1512 }
1513 return IRQ_RETVAL(found);
1514 } /* rx_interrupt */
1515 #endif /* SYNC_SER_DMA */
1516
1517 #ifdef SYNC_SER_MANUAL
manual_interrupt(int irq,void * dev_id)1518 static irqreturn_t manual_interrupt(int irq, void *dev_id)
1519 {
1520 unsigned long flags;
1521 int i;
1522 int found = 0;
1523 reg_sser_r_masked_intr masked;
1524
1525 for (i = 0; i < NBR_PORTS; i++) {
1526 struct sync_port *port = &ports[i];
1527
1528 if (!port->enabled || port->use_dma)
1529 continue;
1530
1531 masked = REG_RD(sser, port->regi_sser, r_masked_intr);
1532 /* Data received? */
1533 if (masked.rdav) {
1534 reg_sser_rw_rec_cfg rec_cfg =
1535 REG_RD(sser, port->regi_sser, rw_rec_cfg);
1536 reg_sser_r_rec_data data = REG_RD(sser,
1537 port->regi_sser, r_rec_data);
1538 found = 1;
1539 /* Read data */
1540 spin_lock_irqsave(&port->lock, flags);
1541 switch (rec_cfg.sample_size) {
1542 case 8:
1543 *port->writep++ = data.data & 0xff;
1544 break;
1545 case 12:
1546 *port->writep = (data.data & 0x0ff0) >> 4;
1547 *(port->writep + 1) = data.data & 0x0f;
1548 port->writep += 2;
1549 break;
1550 case 16:
1551 *(unsigned short *)port->writep = data.data;
1552 port->writep += 2;
1553 break;
1554 case 24:
1555 *(unsigned int *)port->writep = data.data;
1556 port->writep += 3;
1557 break;
1558 case 32:
1559 *(unsigned int *)port->writep = data.data;
1560 port->writep += 4;
1561 break;
1562 }
1563
1564 /* Wrap? */
1565 if (port->writep >= port->flip + port->in_buffer_size)
1566 port->writep = port->flip;
1567 if (port->writep == port->readp) {
1568 /* Receive buf overrun, discard oldest data */
1569 port->readp++;
1570 /* Wrap? */
1571 if (port->readp >= port->flip +
1572 port->in_buffer_size)
1573 port->readp = port->flip;
1574 }
1575 spin_unlock_irqrestore(&port->lock, flags);
1576 if (sync_data_avail(port) >= port->inbufchunk)
1577 /* Wake up application */
1578 wake_up_interruptible(&port->in_wait_q);
1579 }
1580
1581 /* Transmitter ready? */
1582 if (masked.trdy) {
1583 found = 1;
1584 /* More data to send */
1585 if (port->out_buf_count > 0)
1586 send_word(port);
1587 else {
1588 /* Transmission finished */
1589 reg_sser_rw_intr_mask intr_mask;
1590 intr_mask = REG_RD(sser, port->regi_sser,
1591 rw_intr_mask);
1592 intr_mask.trdy = 0;
1593 REG_WR(sser, port->regi_sser,
1594 rw_intr_mask, intr_mask);
1595 /* Wake up application */
1596 wake_up_interruptible(&port->out_wait_q);
1597 }
1598 }
1599 }
1600 return IRQ_RETVAL(found);
1601 }
1602 #endif
1603
etrax_sync_serial_init(void)1604 static int __init etrax_sync_serial_init(void)
1605 {
1606 #if 1
1607 /* This code will be removed when we move to udev for all devices. */
1608 syncser_first = MKDEV(SYNC_SERIAL_MAJOR, 0);
1609 if (register_chrdev_region(syncser_first, minor_count, SYNCSER_NAME)) {
1610 pr_err("Failed to register major %d\n", SYNC_SERIAL_MAJOR);
1611 return -1;
1612 }
1613 #else
1614 /* Allocate dynamic major number. */
1615 if (alloc_chrdev_region(&syncser_first, 0, minor_count, SYNCSER_NAME)) {
1616 pr_err("Failed to allocate character device region\n");
1617 return -1;
1618 }
1619 #endif
1620 syncser_cdev = cdev_alloc();
1621 if (!syncser_cdev) {
1622 pr_err("Failed to allocate cdev for syncser\n");
1623 unregister_chrdev_region(syncser_first, minor_count);
1624 return -1;
1625 }
1626 cdev_init(syncser_cdev, &syncser_fops);
1627
1628 /* Create a sysfs class for syncser */
1629 syncser_class = class_create(THIS_MODULE, "syncser_class");
1630
1631 /* Initialize Ports */
1632 #if defined(CONFIG_ETRAX_SYNCHRONOUS_SERIAL_PORT0)
1633 if (artpec_pinmux_alloc_fixed(PINMUX_SSER0)) {
1634 pr_warn("Unable to alloc pins for synchronous serial port 0\n");
1635 unregister_chrdev_region(syncser_first, minor_count);
1636 return -EIO;
1637 }
1638 initialize_port(0);
1639 ports[0].enabled = 1;
1640 /* Register with sysfs so udev can pick it up. */
1641 device_create(syncser_class, NULL, syncser_first, NULL,
1642 "%s%d", SYNCSER_NAME, 0);
1643 #endif
1644
1645 #if defined(CONFIG_ETRAXFS) && defined(CONFIG_ETRAX_SYNCHRONOUS_SERIAL_PORT1)
1646 if (artpec_pinmux_alloc_fixed(PINMUX_SSER1)) {
1647 pr_warn("Unable to alloc pins for synchronous serial port 1\n");
1648 unregister_chrdev_region(syncser_first, minor_count);
1649 class_destroy(syncser_class);
1650 return -EIO;
1651 }
1652 initialize_port(1);
1653 ports[1].enabled = 1;
1654 /* Register with sysfs so udev can pick it up. */
1655 device_create(syncser_class, NULL, syncser_first, NULL,
1656 "%s%d", SYNCSER_NAME, 0);
1657 #endif
1658
1659 /* Add it to system */
1660 if (cdev_add(syncser_cdev, syncser_first, minor_count) < 0) {
1661 pr_err("Failed to add syncser as char device\n");
1662 device_destroy(syncser_class, syncser_first);
1663 class_destroy(syncser_class);
1664 cdev_del(syncser_cdev);
1665 unregister_chrdev_region(syncser_first, minor_count);
1666 return -1;
1667 }
1668
1669
1670 pr_info("ARTPEC synchronous serial port (%s: %d, %d)\n",
1671 SYNCSER_NAME, MAJOR(syncser_first), MINOR(syncser_first));
1672
1673 return 0;
1674 }
1675
etrax_sync_serial_exit(void)1676 static void __exit etrax_sync_serial_exit(void)
1677 {
1678 int i;
1679 device_destroy(syncser_class, syncser_first);
1680 class_destroy(syncser_class);
1681
1682 if (syncser_cdev) {
1683 cdev_del(syncser_cdev);
1684 unregister_chrdev_region(syncser_first, minor_count);
1685 }
1686 for (i = 0; i < NBR_PORTS; i++) {
1687 struct sync_port *port = &ports[i];
1688 if (port->init_irqs == dma_irq_setup) {
1689 /* Free dma irqs and dma channels. */
1690 #ifdef SYNC_SER_DMA
1691 artpec_free_dma(port->dma_in_nbr);
1692 artpec_free_dma(port->dma_out_nbr);
1693 free_irq(port->dma_out_intr_vect, port);
1694 free_irq(port->dma_in_intr_vect, port);
1695 #endif
1696 } else if (port->init_irqs == manual_irq_setup) {
1697 /* Free manual irq. */
1698 free_irq(port->syncser_intr_vect, port);
1699 }
1700 }
1701
1702 pr_info("ARTPEC synchronous serial port unregistered\n");
1703 }
1704
1705 module_init(etrax_sync_serial_init);
1706 module_exit(etrax_sync_serial_exit);
1707
1708 MODULE_LICENSE("GPL");
1709
1710