Merge branch 'kvm-updates/2.6.36' of git://git.kernel.org/pub/scm/virt/kvm/kvm
[pandora-kernel.git] / arch / cris / arch-v32 / drivers / sync_serial.c
1 /*
2  * Simple synchronous serial port driver for ETRAX FS and Artpec-3.
3  *
4  * Copyright (c) 2005 Axis Communications AB
5  *
6  * Author: Mikael Starvik
7  *
8  */
9
10 #include <linux/module.h>
11 #include <linux/kernel.h>
12 #include <linux/types.h>
13 #include <linux/errno.h>
14 #include <linux/major.h>
15 #include <linux/sched.h>
16 #include <linux/smp_lock.h>
17 #include <linux/interrupt.h>
18 #include <linux/poll.h>
19 #include <linux/init.h>
20 #include <linux/timer.h>
21 #include <linux/spinlock.h>
22
23 #include <asm/io.h>
24 #include <dma.h>
25 #include <pinmux.h>
26 #include <hwregs/reg_rdwr.h>
27 #include <hwregs/sser_defs.h>
28 #include <hwregs/dma_defs.h>
29 #include <hwregs/dma.h>
30 #include <hwregs/intr_vect_defs.h>
31 #include <hwregs/intr_vect.h>
32 #include <hwregs/reg_map.h>
33 #include <asm/sync_serial.h>
34
35
36 /* The receiver is a bit tricky beacuse of the continuous stream of data.*/
37 /*                                                                       */
38 /* Three DMA descriptors are linked together. Each DMA descriptor is     */
39 /* responsible for port->bufchunk of a common buffer.                    */
40 /*                                                                       */
41 /* +---------------------------------------------+                       */
42 /* |   +----------+   +----------+   +----------+ |                      */
43 /* +-> | Descr[0] |-->| Descr[1] |-->| Descr[2] |-+                      */
44 /*     +----------+   +----------+   +----------+                        */
45 /*         |            |              |                                 */
46 /*         v            v              v                                 */
47 /*   +-------------------------------------+                             */
48 /*   |        BUFFER                       |                             */
49 /*   +-------------------------------------+                             */
50 /*      |<- data_avail ->|                                               */
51 /*    readp          writep                                              */
52 /*                                                                       */
53 /* If the application keeps up the pace readp will be right after writep.*/
54 /* If the application can't keep the pace we have to throw away data.    */
55 /* The idea is that readp should be ready with the data pointed out by   */
56 /* Descr[i] when the DMA has filled in Descr[i+1].                       */
57 /* Otherwise we will discard                                             */
58 /* the rest of the data pointed out by Descr1 and set readp to the start */
59 /* of Descr2                                                             */
60
61 #define SYNC_SERIAL_MAJOR 125
62
63 /* IN_BUFFER_SIZE should be a multiple of 6 to make sure that 24 bit */
64 /* words can be handled */
65 #define IN_BUFFER_SIZE 12288
66 #define IN_DESCR_SIZE 256
67 #define NBR_IN_DESCR (IN_BUFFER_SIZE/IN_DESCR_SIZE)
68
69 #define OUT_BUFFER_SIZE 1024*8
70 #define NBR_OUT_DESCR 8
71
72 #define DEFAULT_FRAME_RATE 0
73 #define DEFAULT_WORD_RATE 7
74
75 /* NOTE: Enabling some debug will likely cause overrun or underrun,
76  * especially if manual mode is use.
77  */
78 #define DEBUG(x)
79 #define DEBUGREAD(x)
80 #define DEBUGWRITE(x)
81 #define DEBUGPOLL(x)
82 #define DEBUGRXINT(x)
83 #define DEBUGTXINT(x)
84 #define DEBUGTRDMA(x)
85 #define DEBUGOUTBUF(x)
86
87 typedef struct sync_port
88 {
89         reg_scope_instances regi_sser;
90         reg_scope_instances regi_dmain;
91         reg_scope_instances regi_dmaout;
92
93         char started; /* 1 if port has been started */
94         char port_nbr; /* Port 0 or 1 */
95         char busy; /* 1 if port is busy */
96
97         char enabled;  /* 1 if port is enabled */
98         char use_dma;  /* 1 if port uses dma */
99         char tr_running;
100
101         char init_irqs;
102         int output;
103         int input;
104
105         /* Next byte to be read by application */
106         volatile unsigned char *volatile readp;
107         /* Next byte to be written by etrax */
108         volatile unsigned char *volatile writep;
109
110         unsigned int in_buffer_size;
111         unsigned int inbufchunk;
112         unsigned char out_buffer[OUT_BUFFER_SIZE] __attribute__ ((aligned(32)));
113         unsigned char in_buffer[IN_BUFFER_SIZE]__attribute__ ((aligned(32)));
114         unsigned char flip[IN_BUFFER_SIZE] __attribute__ ((aligned(32)));
115         struct dma_descr_data* next_rx_desc;
116         struct dma_descr_data* prev_rx_desc;
117
118         /* Pointer to the first available descriptor in the ring,
119          * unless active_tr_descr == catch_tr_descr and a dma
120          * transfer is active */
121         struct dma_descr_data *active_tr_descr;
122
123         /* Pointer to the first allocated descriptor in the ring */
124         struct dma_descr_data *catch_tr_descr;
125
126         /* Pointer to the descriptor with the current end-of-list */
127         struct dma_descr_data *prev_tr_descr;
128         int full;
129
130         /* Pointer to the first byte being read by DMA
131          * or current position in out_buffer if not using DMA. */
132         unsigned char *out_rd_ptr;
133
134         /* Number of bytes currently locked for being read by DMA */
135         int out_buf_count;
136
137         dma_descr_data in_descr[NBR_IN_DESCR] __attribute__ ((__aligned__(16)));
138         dma_descr_context in_context __attribute__ ((__aligned__(32)));
139         dma_descr_data out_descr[NBR_OUT_DESCR]
140                 __attribute__ ((__aligned__(16)));
141         dma_descr_context out_context __attribute__ ((__aligned__(32)));
142         wait_queue_head_t out_wait_q;
143         wait_queue_head_t in_wait_q;
144
145         spinlock_t lock;
146 } sync_port;
147
148 static int etrax_sync_serial_init(void);
149 static void initialize_port(int portnbr);
150 static inline int sync_data_avail(struct sync_port *port);
151
152 static int sync_serial_open(struct inode *, struct file*);
153 static int sync_serial_release(struct inode*, struct file*);
154 static unsigned int sync_serial_poll(struct file *filp, poll_table *wait);
155
156 static int sync_serial_ioctl(struct file *,
157                              unsigned int cmd, unsigned long arg);
158 static ssize_t sync_serial_write(struct file * file, const char * buf,
159                                  size_t count, loff_t *ppos);
160 static ssize_t sync_serial_read(struct file *file, char *buf,
161                                 size_t count, loff_t *ppos);
162
163 #if (defined(CONFIG_ETRAX_SYNCHRONOUS_SERIAL_PORT0) && \
164      defined(CONFIG_ETRAX_SYNCHRONOUS_SERIAL0_DMA)) || \
165     (defined(CONFIG_ETRAX_SYNCHRONOUS_SERIAL_PORT1) && \
166      defined(CONFIG_ETRAX_SYNCHRONOUS_SERIAL1_DMA))
167 #define SYNC_SER_DMA
168 #endif
169
170 static void send_word(sync_port* port);
171 static void start_dma_out(struct sync_port *port, const char *data, int count);
172 static void start_dma_in(sync_port* port);
173 #ifdef SYNC_SER_DMA
174 static irqreturn_t tr_interrupt(int irq, void *dev_id);
175 static irqreturn_t rx_interrupt(int irq, void *dev_id);
176 #endif
177
178 #if (defined(CONFIG_ETRAX_SYNCHRONOUS_SERIAL_PORT0) && \
179      !defined(CONFIG_ETRAX_SYNCHRONOUS_SERIAL0_DMA)) || \
180     (defined(CONFIG_ETRAX_SYNCHRONOUS_SERIAL_PORT1) && \
181      !defined(CONFIG_ETRAX_SYNCHRONOUS_SERIAL1_DMA))
182 #define SYNC_SER_MANUAL
183 #endif
184 #ifdef SYNC_SER_MANUAL
185 static irqreturn_t manual_interrupt(int irq, void *dev_id);
186 #endif
187
188 #ifdef CONFIG_ETRAXFS   /* ETRAX FS */
189 #define OUT_DMA_NBR 4
190 #define IN_DMA_NBR 5
191 #define PINMUX_SSER pinmux_sser0
192 #define SYNCSER_INST regi_sser0
193 #define SYNCSER_INTR_VECT SSER0_INTR_VECT
194 #define OUT_DMA_INST regi_dma4
195 #define IN_DMA_INST regi_dma5
196 #define DMA_OUT_INTR_VECT DMA4_INTR_VECT
197 #define DMA_IN_INTR_VECT DMA5_INTR_VECT
198 #define REQ_DMA_SYNCSER dma_sser0
199 #else                   /* Artpec-3 */
200 #define OUT_DMA_NBR 6
201 #define IN_DMA_NBR 7
202 #define PINMUX_SSER pinmux_sser
203 #define SYNCSER_INST regi_sser
204 #define SYNCSER_INTR_VECT SSER_INTR_VECT
205 #define OUT_DMA_INST regi_dma6
206 #define IN_DMA_INST regi_dma7
207 #define DMA_OUT_INTR_VECT DMA6_INTR_VECT
208 #define DMA_IN_INTR_VECT DMA7_INTR_VECT
209 #define REQ_DMA_SYNCSER dma_sser
210 #endif
211
212 /* The ports */
213 static struct sync_port ports[]=
214 {
215         {
216                 .regi_sser             = SYNCSER_INST,
217                 .regi_dmaout           = OUT_DMA_INST,
218                 .regi_dmain            = IN_DMA_INST,
219 #if defined(CONFIG_ETRAX_SYNCHRONOUS_SERIAL0_DMA)
220                 .use_dma               = 1,
221 #else
222                 .use_dma               = 0,
223 #endif
224         }
225 #ifdef CONFIG_ETRAXFS
226         ,
227
228         {
229                 .regi_sser             = regi_sser1,
230                 .regi_dmaout           = regi_dma6,
231                 .regi_dmain            = regi_dma7,
232 #if defined(CONFIG_ETRAX_SYNCHRONOUS_SERIAL1_DMA)
233                 .use_dma               = 1,
234 #else
235                 .use_dma               = 0,
236 #endif
237         }
238 #endif
239 };
240
241 #define NBR_PORTS ARRAY_SIZE(ports)
242
243 static const struct file_operations sync_serial_fops = {
244         .owner          = THIS_MODULE,
245         .write          = sync_serial_write,
246         .read           = sync_serial_read,
247         .poll           = sync_serial_poll,
248         .unlocked_ioctl = sync_serial_ioctl,
249         .open           = sync_serial_open,
250         .release        = sync_serial_release
251 };
252
253 static int __init etrax_sync_serial_init(void)
254 {
255         ports[0].enabled = 0;
256 #ifdef CONFIG_ETRAXFS
257         ports[1].enabled = 0;
258 #endif
259         if (register_chrdev(SYNC_SERIAL_MAJOR, "sync serial",
260                         &sync_serial_fops) < 0) {
261                 printk(KERN_WARNING
262                         "Unable to get major for synchronous serial port\n");
263                 return -EBUSY;
264         }
265
266         /* Initialize Ports */
267 #if defined(CONFIG_ETRAX_SYNCHRONOUS_SERIAL_PORT0)
268         if (crisv32_pinmux_alloc_fixed(PINMUX_SSER)) {
269                 printk(KERN_WARNING
270                         "Unable to alloc pins for synchronous serial port 0\n");
271                 return -EIO;
272         }
273         ports[0].enabled = 1;
274         initialize_port(0);
275 #endif
276
277 #if defined(CONFIG_ETRAX_SYNCHRONOUS_SERIAL_PORT1)
278         if (crisv32_pinmux_alloc_fixed(pinmux_sser1)) {
279                 printk(KERN_WARNING
280                         "Unable to alloc pins for synchronous serial port 0\n");
281                 return -EIO;
282         }
283         ports[1].enabled = 1;
284         initialize_port(1);
285 #endif
286
287 #ifdef CONFIG_ETRAXFS
288         printk(KERN_INFO "ETRAX FS synchronous serial port driver\n");
289 #else
290         printk(KERN_INFO "Artpec-3 synchronous serial port driver\n");
291 #endif
292         return 0;
293 }
294
295 static void __init initialize_port(int portnbr)
296 {
297         int __attribute__((unused)) i;
298         struct sync_port *port = &ports[portnbr];
299         reg_sser_rw_cfg cfg = {0};
300         reg_sser_rw_frm_cfg frm_cfg = {0};
301         reg_sser_rw_tr_cfg tr_cfg = {0};
302         reg_sser_rw_rec_cfg rec_cfg = {0};
303
304         DEBUG(printk(KERN_DEBUG "Init sync serial port %d\n", portnbr));
305
306         port->port_nbr = portnbr;
307         port->init_irqs = 1;
308
309         port->out_rd_ptr = port->out_buffer;
310         port->out_buf_count = 0;
311
312         port->output = 1;
313         port->input = 0;
314
315         port->readp = port->flip;
316         port->writep = port->flip;
317         port->in_buffer_size = IN_BUFFER_SIZE;
318         port->inbufchunk = IN_DESCR_SIZE;
319         port->next_rx_desc = &port->in_descr[0];
320         port->prev_rx_desc = &port->in_descr[NBR_IN_DESCR-1];
321         port->prev_rx_desc->eol = 1;
322
323         init_waitqueue_head(&port->out_wait_q);
324         init_waitqueue_head(&port->in_wait_q);
325
326         spin_lock_init(&port->lock);
327
328         cfg.out_clk_src = regk_sser_intern_clk;
329         cfg.out_clk_pol = regk_sser_pos;
330         cfg.clk_od_mode = regk_sser_no;
331         cfg.clk_dir = regk_sser_out;
332         cfg.gate_clk = regk_sser_no;
333         cfg.base_freq = regk_sser_f29_493;
334         cfg.clk_div = 256;
335         REG_WR(sser, port->regi_sser, rw_cfg, cfg);
336
337         frm_cfg.wordrate = DEFAULT_WORD_RATE;
338         frm_cfg.type = regk_sser_edge;
339         frm_cfg.frame_pin_dir = regk_sser_out;
340         frm_cfg.frame_pin_use = regk_sser_frm;
341         frm_cfg.status_pin_dir = regk_sser_in;
342         frm_cfg.status_pin_use = regk_sser_hold;
343         frm_cfg.out_on = regk_sser_tr;
344         frm_cfg.tr_delay = 1;
345         REG_WR(sser, port->regi_sser, rw_frm_cfg, frm_cfg);
346
347         tr_cfg.urun_stop = regk_sser_no;
348         tr_cfg.sample_size = 7;
349         tr_cfg.sh_dir = regk_sser_msbfirst;
350         tr_cfg.use_dma = port->use_dma ? regk_sser_yes : regk_sser_no;
351 #if 0
352         tr_cfg.rate_ctrl = regk_sser_bulk;
353         tr_cfg.data_pin_use = regk_sser_dout;
354 #else
355         tr_cfg.rate_ctrl = regk_sser_iso;
356         tr_cfg.data_pin_use = regk_sser_dout;
357 #endif
358         tr_cfg.bulk_wspace = 1;
359         REG_WR(sser, port->regi_sser, rw_tr_cfg, tr_cfg);
360
361         rec_cfg.sample_size = 7;
362         rec_cfg.sh_dir = regk_sser_msbfirst;
363         rec_cfg.use_dma = port->use_dma ? regk_sser_yes : regk_sser_no;
364         rec_cfg.fifo_thr = regk_sser_inf;
365         REG_WR(sser, port->regi_sser, rw_rec_cfg, rec_cfg);
366
367 #ifdef SYNC_SER_DMA
368         /* Setup the descriptor ring for dma out/transmit. */
369         for (i = 0; i < NBR_OUT_DESCR; i++) {
370                 port->out_descr[i].wait = 0;
371                 port->out_descr[i].intr = 1;
372                 port->out_descr[i].eol = 0;
373                 port->out_descr[i].out_eop = 0;
374                 port->out_descr[i].next =
375                         (dma_descr_data *)virt_to_phys(&port->out_descr[i+1]);
376         }
377
378         /* Create a ring from the list. */
379         port->out_descr[NBR_OUT_DESCR-1].next =
380                 (dma_descr_data *)virt_to_phys(&port->out_descr[0]);
381
382         /* Setup context for traversing the ring. */
383         port->active_tr_descr = &port->out_descr[0];
384         port->prev_tr_descr = &port->out_descr[NBR_OUT_DESCR-1];
385         port->catch_tr_descr = &port->out_descr[0];
386 #endif
387 }
388
389 static inline int sync_data_avail(struct sync_port *port)
390 {
391         int avail;
392         unsigned char *start;
393         unsigned char *end;
394
395         start = (unsigned char*)port->readp; /* cast away volatile */
396         end = (unsigned char*)port->writep;  /* cast away volatile */
397         /* 0123456789  0123456789
398          *  -----      -    -----
399          *  ^rp  ^wp    ^wp ^rp
400          */
401
402         if (end >= start)
403                 avail = end - start;
404         else
405                 avail = port->in_buffer_size - (start - end);
406         return avail;
407 }
408
409 static inline int sync_data_avail_to_end(struct sync_port *port)
410 {
411         int avail;
412         unsigned char *start;
413         unsigned char *end;
414
415         start = (unsigned char*)port->readp; /* cast away volatile */
416         end = (unsigned char*)port->writep;  /* cast away volatile */
417         /* 0123456789  0123456789
418          *  -----           -----
419          *  ^rp  ^wp    ^wp ^rp
420          */
421
422         if (end >= start)
423                 avail = end - start;
424         else
425                 avail = port->flip + port->in_buffer_size - start;
426         return avail;
427 }
428
429 static int sync_serial_open(struct inode *inode, struct file *file)
430 {
431         int dev = iminor(inode);
432         int ret = -EBUSY;
433         sync_port *port;
434         reg_dma_rw_cfg cfg = {.en = regk_dma_yes};
435         reg_dma_rw_intr_mask intr_mask = {.data = regk_dma_yes};
436
437         lock_kernel();
438         DEBUG(printk(KERN_DEBUG "Open sync serial port %d\n", dev));
439
440         if (dev < 0 || dev >= NBR_PORTS || !ports[dev].enabled)
441         {
442                 DEBUG(printk(KERN_DEBUG "Invalid minor %d\n", dev));
443                 ret = -ENODEV;
444                 goto out;
445         }
446         port = &ports[dev];
447         /* Allow open this device twice (assuming one reader and one writer) */
448         if (port->busy == 2)
449         {
450                 DEBUG(printk(KERN_DEBUG "Device is busy.. \n"));
451                 goto out;
452         }
453
454
455         if (port->init_irqs) {
456                 if (port->use_dma) {
457                         if (port == &ports[0]) {
458 #ifdef SYNC_SER_DMA
459                                 if (request_irq(DMA_OUT_INTR_VECT,
460                                                 tr_interrupt,
461                                                 0,
462                                                 "synchronous serial 0 dma tr",
463                                                 &ports[0])) {
464                                         printk(KERN_CRIT "Can't allocate sync serial port 0 IRQ");
465                                         goto out;
466                                 } else if (request_irq(DMA_IN_INTR_VECT,
467                                                 rx_interrupt,
468                                                 0,
469                                                 "synchronous serial 1 dma rx",
470                                                 &ports[0])) {
471                                         free_irq(DMA_OUT_INTR_VECT, &port[0]);
472                                         printk(KERN_CRIT "Can't allocate sync serial port 0 IRQ");
473                                         goto out;
474                                 } else if (crisv32_request_dma(OUT_DMA_NBR,
475                                                 "synchronous serial 0 dma tr",
476                                                 DMA_VERBOSE_ON_ERROR,
477                                                 0,
478                                                 REQ_DMA_SYNCSER)) {
479                                         free_irq(DMA_OUT_INTR_VECT, &port[0]);
480                                         free_irq(DMA_IN_INTR_VECT, &port[0]);
481                                         printk(KERN_CRIT "Can't allocate sync serial port 0 TX DMA channel");
482                                         goto out;
483                                 } else if (crisv32_request_dma(IN_DMA_NBR,
484                                                 "synchronous serial 0 dma rec",
485                                                 DMA_VERBOSE_ON_ERROR,
486                                                 0,
487                                                 REQ_DMA_SYNCSER)) {
488                                         crisv32_free_dma(OUT_DMA_NBR);
489                                         free_irq(DMA_OUT_INTR_VECT, &port[0]);
490                                         free_irq(DMA_IN_INTR_VECT, &port[0]);
491                                         printk(KERN_CRIT "Can't allocate sync serial port 1 RX DMA channel");
492                                         goto out;
493                                 }
494 #endif
495                         }
496 #ifdef CONFIG_ETRAXFS
497                         else if (port == &ports[1]) {
498 #ifdef SYNC_SER_DMA
499                                 if (request_irq(DMA6_INTR_VECT,
500                                                 tr_interrupt,
501                                                 0,
502                                                 "synchronous serial 1 dma tr",
503                                                 &ports[1])) {
504                                         printk(KERN_CRIT "Can't allocate sync serial port 1 IRQ");
505                                         goto out;
506                                 } else if (request_irq(DMA7_INTR_VECT,
507                                                        rx_interrupt,
508                                                        0,
509                                                        "synchronous serial 1 dma rx",
510                                                        &ports[1])) {
511                                         free_irq(DMA6_INTR_VECT, &ports[1]);
512                                         printk(KERN_CRIT "Can't allocate sync serial port 3 IRQ");
513                                         goto out;
514                                 } else if (crisv32_request_dma(
515                                                 SYNC_SER1_TX_DMA_NBR,
516                                                 "synchronous serial 1 dma tr",
517                                                 DMA_VERBOSE_ON_ERROR,
518                                                 0,
519                                                 dma_sser1)) {
520                                         free_irq(DMA6_INTR_VECT, &ports[1]);
521                                         free_irq(DMA7_INTR_VECT, &ports[1]);
522                                         printk(KERN_CRIT "Can't allocate sync serial port 3 TX DMA channel");
523                                         goto out;
524                                 } else if (crisv32_request_dma(
525                                                 SYNC_SER1_RX_DMA_NBR,
526                                                 "synchronous serial 3 dma rec",
527                                                 DMA_VERBOSE_ON_ERROR,
528                                                 0,
529                                                 dma_sser1)) {
530                                         crisv32_free_dma(SYNC_SER1_TX_DMA_NBR);
531                                         free_irq(DMA6_INTR_VECT, &ports[1]);
532                                         free_irq(DMA7_INTR_VECT, &ports[1]);
533                                         printk(KERN_CRIT "Can't allocate sync serial port 3 RX DMA channel");
534                                         goto out;
535                                 }
536 #endif
537                         }
538 #endif
539                         /* Enable DMAs */
540                         REG_WR(dma, port->regi_dmain, rw_cfg, cfg);
541                         REG_WR(dma, port->regi_dmaout, rw_cfg, cfg);
542                         /* Enable DMA IRQs */
543                         REG_WR(dma, port->regi_dmain, rw_intr_mask, intr_mask);
544                         REG_WR(dma, port->regi_dmaout, rw_intr_mask, intr_mask);
545                         /* Set up wordsize = 1 for DMAs. */
546                         DMA_WR_CMD (port->regi_dmain, regk_dma_set_w_size1);
547                         DMA_WR_CMD (port->regi_dmaout, regk_dma_set_w_size1);
548
549                         start_dma_in(port);
550                         port->init_irqs = 0;
551                 } else { /* !port->use_dma */
552 #ifdef SYNC_SER_MANUAL
553                         if (port == &ports[0]) {
554                                 if (request_irq(SYNCSER_INTR_VECT,
555                                                 manual_interrupt,
556                                                 0,
557                                                 "synchronous serial manual irq",
558                                                 &ports[0])) {
559                                         printk("Can't allocate sync serial manual irq");
560                                         goto out;
561                                 }
562                         }
563 #ifdef CONFIG_ETRAXFS
564                         else if (port == &ports[1]) {
565                                 if (request_irq(SSER1_INTR_VECT,
566                                                 manual_interrupt,
567                                                 0,
568                                                 "synchronous serial manual irq",
569                                                 &ports[1])) {
570                                         printk(KERN_CRIT "Can't allocate sync serial manual irq");
571                                         goto out;
572                                 }
573                         }
574 #endif
575                         port->init_irqs = 0;
576 #else
577                         panic("sync_serial: Manual mode not supported.\n");
578 #endif /* SYNC_SER_MANUAL */
579                 }
580
581         } /* port->init_irqs */
582
583         port->busy++;
584         ret = 0;
585 out:
586         unlock_kernel();
587         return ret;
588 }
589
590 static int sync_serial_release(struct inode *inode, struct file *file)
591 {
592         int dev = iminor(inode);
593         sync_port *port;
594
595         if (dev < 0 || dev >= NBR_PORTS || !ports[dev].enabled)
596         {
597                 DEBUG(printk("Invalid minor %d\n", dev));
598                 return -ENODEV;
599         }
600         port = &ports[dev];
601         if (port->busy)
602                 port->busy--;
603         if (!port->busy)
604           /* XXX */ ;
605         return 0;
606 }
607
608 static unsigned int sync_serial_poll(struct file *file, poll_table *wait)
609 {
610         int dev = iminor(file->f_path.dentry->d_inode);
611         unsigned int mask = 0;
612         sync_port *port;
613         DEBUGPOLL( static unsigned int prev_mask = 0; );
614
615         port = &ports[dev];
616
617         if (!port->started) {
618                 reg_sser_rw_cfg cfg = REG_RD(sser, port->regi_sser, rw_cfg);
619                 reg_sser_rw_rec_cfg rec_cfg =
620                         REG_RD(sser, port->regi_sser, rw_rec_cfg);
621                 cfg.en = regk_sser_yes;
622                 rec_cfg.rec_en = port->input;
623                 REG_WR(sser, port->regi_sser, rw_cfg, cfg);
624                 REG_WR(sser, port->regi_sser, rw_rec_cfg, rec_cfg);
625                 port->started = 1;
626         }
627
628         poll_wait(file, &port->out_wait_q, wait);
629         poll_wait(file, &port->in_wait_q, wait);
630
631         /* No active transfer, descriptors are available */
632         if (port->output && !port->tr_running)
633                 mask |= POLLOUT | POLLWRNORM;
634
635         /* Descriptor and buffer space available. */
636         if (port->output &&
637             port->active_tr_descr != port->catch_tr_descr &&
638             port->out_buf_count < OUT_BUFFER_SIZE)
639                 mask |=  POLLOUT | POLLWRNORM;
640
641         /* At least an inbufchunk of data */
642         if (port->input && sync_data_avail(port) >= port->inbufchunk)
643                 mask |= POLLIN | POLLRDNORM;
644
645         DEBUGPOLL(if (mask != prev_mask)
646               printk("sync_serial_poll: mask 0x%08X %s %s\n", mask,
647                      mask&POLLOUT?"POLLOUT":"", mask&POLLIN?"POLLIN":"");
648               prev_mask = mask;
649               );
650         return mask;
651 }
652
653 static int sync_serial_ioctl(struct file *file,
654                   unsigned int cmd, unsigned long arg)
655 {
656         int return_val = 0;
657         int dma_w_size = regk_dma_set_w_size1;
658         int dev = iminor(file->f_path.dentry->d_inode);
659         sync_port *port;
660         reg_sser_rw_tr_cfg tr_cfg;
661         reg_sser_rw_rec_cfg rec_cfg;
662         reg_sser_rw_frm_cfg frm_cfg;
663         reg_sser_rw_cfg gen_cfg;
664         reg_sser_rw_intr_mask intr_mask;
665
666         if (dev < 0 || dev >= NBR_PORTS || !ports[dev].enabled)
667         {
668                 DEBUG(printk("Invalid minor %d\n", dev));
669                 return -1;
670         }
671         port = &ports[dev];
672         spin_lock_irq(&port->lock);
673
674         tr_cfg = REG_RD(sser, port->regi_sser, rw_tr_cfg);
675         rec_cfg = REG_RD(sser, port->regi_sser, rw_rec_cfg);
676         frm_cfg = REG_RD(sser, port->regi_sser, rw_frm_cfg);
677         gen_cfg = REG_RD(sser, port->regi_sser, rw_cfg);
678         intr_mask = REG_RD(sser, port->regi_sser, rw_intr_mask);
679
680         switch(cmd)
681         {
682         case SSP_SPEED:
683                 if (GET_SPEED(arg) == CODEC)
684                 {
685                         unsigned int freq;
686
687                         gen_cfg.base_freq = regk_sser_f32;
688
689                         /* Clock divider will internally be
690                          * gen_cfg.clk_div + 1.
691                          */
692
693                         freq = GET_FREQ(arg);
694                         switch (freq) {
695                         case FREQ_32kHz:
696                         case FREQ_64kHz:
697                         case FREQ_128kHz:
698                         case FREQ_256kHz:
699                                 gen_cfg.clk_div = 125 *
700                                         (1 << (freq - FREQ_256kHz)) - 1;
701                         break;
702                         case FREQ_512kHz:
703                                 gen_cfg.clk_div = 62;
704                         break;
705                         case FREQ_1MHz:
706                         case FREQ_2MHz:
707                         case FREQ_4MHz:
708                                 gen_cfg.clk_div = 8 * (1 << freq) - 1;
709                         break;
710                         }
711                 } else {
712                         gen_cfg.base_freq = regk_sser_f29_493;
713                         switch (GET_SPEED(arg)) {
714                         case SSP150:
715                                 gen_cfg.clk_div = 29493000 / (150 * 8) - 1;
716                                 break;
717                         case SSP300:
718                                 gen_cfg.clk_div = 29493000 / (300 * 8) - 1;
719                                 break;
720                         case SSP600:
721                                 gen_cfg.clk_div = 29493000 / (600 * 8) - 1;
722                                 break;
723                         case SSP1200:
724                                 gen_cfg.clk_div = 29493000 / (1200 * 8) - 1;
725                                 break;
726                         case SSP2400:
727                                 gen_cfg.clk_div = 29493000 / (2400 * 8) - 1;
728                                 break;
729                         case SSP4800:
730                                 gen_cfg.clk_div = 29493000 / (4800 * 8) - 1;
731                                 break;
732                         case SSP9600:
733                                 gen_cfg.clk_div = 29493000 / (9600 * 8) - 1;
734                                 break;
735                         case SSP19200:
736                                 gen_cfg.clk_div = 29493000 / (19200 * 8) - 1;
737                                 break;
738                         case SSP28800:
739                                 gen_cfg.clk_div = 29493000 / (28800 * 8) - 1;
740                                 break;
741                         case SSP57600:
742                                 gen_cfg.clk_div = 29493000 / (57600 * 8) - 1;
743                                 break;
744                         case SSP115200:
745                                 gen_cfg.clk_div = 29493000 / (115200 * 8) - 1;
746                                 break;
747                         case SSP230400:
748                                 gen_cfg.clk_div = 29493000 / (230400 * 8) - 1;
749                                 break;
750                         case SSP460800:
751                                 gen_cfg.clk_div = 29493000 / (460800 * 8) - 1;
752                                 break;
753                         case SSP921600:
754                                 gen_cfg.clk_div = 29493000 / (921600 * 8) - 1;
755                                 break;
756                         case SSP3125000:
757                                 gen_cfg.base_freq = regk_sser_f100;
758                                 gen_cfg.clk_div = 100000000 / (3125000 * 8) - 1;
759                                 break;
760
761                         }
762                 }
763                 frm_cfg.wordrate = GET_WORD_RATE(arg);
764
765                 break;
766         case SSP_MODE:
767                 switch(arg)
768                 {
769                         case MASTER_OUTPUT:
770                                 port->output = 1;
771                                 port->input = 0;
772                                 frm_cfg.out_on = regk_sser_tr;
773                                 frm_cfg.frame_pin_dir = regk_sser_out;
774                                 gen_cfg.clk_dir = regk_sser_out;
775                                 break;
776                         case SLAVE_OUTPUT:
777                                 port->output = 1;
778                                 port->input = 0;
779                                 frm_cfg.frame_pin_dir = regk_sser_in;
780                                 gen_cfg.clk_dir = regk_sser_in;
781                                 break;
782                         case MASTER_INPUT:
783                                 port->output = 0;
784                                 port->input = 1;
785                                 frm_cfg.frame_pin_dir = regk_sser_out;
786                                 frm_cfg.out_on = regk_sser_intern_tb;
787                                 gen_cfg.clk_dir = regk_sser_out;
788                                 break;
789                         case SLAVE_INPUT:
790                                 port->output = 0;
791                                 port->input = 1;
792                                 frm_cfg.frame_pin_dir = regk_sser_in;
793                                 gen_cfg.clk_dir = regk_sser_in;
794                                 break;
795                         case MASTER_BIDIR:
796                                 port->output = 1;
797                                 port->input = 1;
798                                 frm_cfg.frame_pin_dir = regk_sser_out;
799                                 frm_cfg.out_on = regk_sser_intern_tb;
800                                 gen_cfg.clk_dir = regk_sser_out;
801                                 break;
802                         case SLAVE_BIDIR:
803                                 port->output = 1;
804                                 port->input = 1;
805                                 frm_cfg.frame_pin_dir = regk_sser_in;
806                                 gen_cfg.clk_dir = regk_sser_in;
807                                 break;
808                         default:
809                                 spin_unlock_irq(&port->lock);
810                                 return -EINVAL;
811                 }
812                 if (!port->use_dma || (arg == MASTER_OUTPUT || arg == SLAVE_OUTPUT))
813                         intr_mask.rdav = regk_sser_yes;
814                 break;
815         case SSP_FRAME_SYNC:
816                 if (arg & NORMAL_SYNC) {
817                         frm_cfg.rec_delay = 1;
818                         frm_cfg.tr_delay = 1;
819                 }
820                 else if (arg & EARLY_SYNC)
821                         frm_cfg.rec_delay = frm_cfg.tr_delay = 0;
822                 else if (arg & SECOND_WORD_SYNC) {
823                         frm_cfg.rec_delay = 7;
824                         frm_cfg.tr_delay = 1;
825                 }
826
827                 tr_cfg.bulk_wspace = frm_cfg.tr_delay;
828                 frm_cfg.early_wend = regk_sser_yes;
829                 if (arg & BIT_SYNC)
830                         frm_cfg.type = regk_sser_edge;
831                 else if (arg & WORD_SYNC)
832                         frm_cfg.type = regk_sser_level;
833                 else if (arg & EXTENDED_SYNC)
834                         frm_cfg.early_wend = regk_sser_no;
835
836                 if (arg & SYNC_ON)
837                         frm_cfg.frame_pin_use = regk_sser_frm;
838                 else if (arg & SYNC_OFF)
839                         frm_cfg.frame_pin_use = regk_sser_gio0;
840
841                 dma_w_size = regk_dma_set_w_size2;
842                 if (arg & WORD_SIZE_8) {
843                         rec_cfg.sample_size = tr_cfg.sample_size = 7;
844                         dma_w_size = regk_dma_set_w_size1;
845                 } else if (arg & WORD_SIZE_12)
846                         rec_cfg.sample_size = tr_cfg.sample_size = 11;
847                 else if (arg & WORD_SIZE_16)
848                         rec_cfg.sample_size = tr_cfg.sample_size = 15;
849                 else if (arg & WORD_SIZE_24)
850                         rec_cfg.sample_size = tr_cfg.sample_size = 23;
851                 else if (arg & WORD_SIZE_32)
852                         rec_cfg.sample_size = tr_cfg.sample_size = 31;
853
854                 if (arg & BIT_ORDER_MSB)
855                         rec_cfg.sh_dir = tr_cfg.sh_dir = regk_sser_msbfirst;
856                 else if (arg & BIT_ORDER_LSB)
857                         rec_cfg.sh_dir = tr_cfg.sh_dir = regk_sser_lsbfirst;
858
859                 if (arg & FLOW_CONTROL_ENABLE) {
860                         frm_cfg.status_pin_use = regk_sser_frm;
861                         rec_cfg.fifo_thr = regk_sser_thr16;
862                 } else if (arg & FLOW_CONTROL_DISABLE) {
863                         frm_cfg.status_pin_use = regk_sser_gio0;
864                         rec_cfg.fifo_thr = regk_sser_inf;
865                 }
866
867                 if (arg & CLOCK_NOT_GATED)
868                         gen_cfg.gate_clk = regk_sser_no;
869                 else if (arg & CLOCK_GATED)
870                         gen_cfg.gate_clk = regk_sser_yes;
871
872                 break;
873         case SSP_IPOLARITY:
874                 /* NOTE!! negedge is considered NORMAL */
875                 if (arg & CLOCK_NORMAL)
876                         rec_cfg.clk_pol = regk_sser_neg;
877                 else if (arg & CLOCK_INVERT)
878                         rec_cfg.clk_pol = regk_sser_pos;
879
880                 if (arg & FRAME_NORMAL)
881                         frm_cfg.level = regk_sser_pos_hi;
882                 else if (arg & FRAME_INVERT)
883                         frm_cfg.level = regk_sser_neg_lo;
884
885                 if (arg & STATUS_NORMAL)
886                         gen_cfg.hold_pol = regk_sser_pos;
887                 else if (arg & STATUS_INVERT)
888                         gen_cfg.hold_pol = regk_sser_neg;
889                 break;
890         case SSP_OPOLARITY:
891                 if (arg & CLOCK_NORMAL)
892                         gen_cfg.out_clk_pol = regk_sser_pos;
893                 else if (arg & CLOCK_INVERT)
894                         gen_cfg.out_clk_pol = regk_sser_neg;
895
896                 if (arg & FRAME_NORMAL)
897                         frm_cfg.level = regk_sser_pos_hi;
898                 else if (arg & FRAME_INVERT)
899                         frm_cfg.level = regk_sser_neg_lo;
900
901                 if (arg & STATUS_NORMAL)
902                         gen_cfg.hold_pol = regk_sser_pos;
903                 else if (arg & STATUS_INVERT)
904                         gen_cfg.hold_pol = regk_sser_neg;
905                 break;
906         case SSP_SPI:
907                 rec_cfg.fifo_thr = regk_sser_inf;
908                 rec_cfg.sh_dir = tr_cfg.sh_dir = regk_sser_msbfirst;
909                 rec_cfg.sample_size = tr_cfg.sample_size = 7;
910                 frm_cfg.frame_pin_use = regk_sser_frm;
911                 frm_cfg.type = regk_sser_level;
912                 frm_cfg.tr_delay = 1;
913                 frm_cfg.level = regk_sser_neg_lo;
914                 if (arg & SPI_SLAVE)
915                 {
916                         rec_cfg.clk_pol = regk_sser_neg;
917                         gen_cfg.clk_dir = regk_sser_in;
918                         port->input = 1;
919                         port->output = 0;
920                 }
921                 else
922                 {
923                         gen_cfg.out_clk_pol = regk_sser_pos;
924                         port->input = 0;
925                         port->output = 1;
926                         gen_cfg.clk_dir = regk_sser_out;
927                 }
928                 break;
929         case SSP_INBUFCHUNK:
930                 break;
931         default:
932                 return_val = -1;
933         }
934
935
936         if (port->started) {
937                 rec_cfg.rec_en = port->input;
938                 gen_cfg.en = (port->output | port->input);
939         }
940
941         REG_WR(sser, port->regi_sser, rw_tr_cfg, tr_cfg);
942         REG_WR(sser, port->regi_sser, rw_rec_cfg, rec_cfg);
943         REG_WR(sser, port->regi_sser, rw_frm_cfg, frm_cfg);
944         REG_WR(sser, port->regi_sser, rw_intr_mask, intr_mask);
945         REG_WR(sser, port->regi_sser, rw_cfg, gen_cfg);
946
947
948         if (cmd == SSP_FRAME_SYNC && (arg & (WORD_SIZE_8 | WORD_SIZE_12 |
949                         WORD_SIZE_16 | WORD_SIZE_24 | WORD_SIZE_32))) {
950                 int en = gen_cfg.en;
951                 gen_cfg.en = 0;
952                 REG_WR(sser, port->regi_sser, rw_cfg, gen_cfg);
953                 /* ##### Should DMA be stoped before we change dma size? */
954                 DMA_WR_CMD(port->regi_dmain, dma_w_size);
955                 DMA_WR_CMD(port->regi_dmaout, dma_w_size);
956                 gen_cfg.en = en;
957                 REG_WR(sser, port->regi_sser, rw_cfg, gen_cfg);
958         }
959
960         spin_unlock_irq(&port->lock);
961         return return_val;
962 }
963
964 static long sync_serial_ioctl(struct file *file,
965                              unsigned int cmd, unsigned long arg)
966 {
967        long ret;
968
969        lock_kernel();
970        ret = sync_serial_ioctl_unlocked(file, cmd, arg);
971        unlock_kernel();
972
973        return ret;
974 }
975
976 /* NOTE: sync_serial_write does not support concurrency */
977 static ssize_t sync_serial_write(struct file *file, const char *buf,
978                                  size_t count, loff_t *ppos)
979 {
980         int dev = iminor(file->f_path.dentry->d_inode);
981         DECLARE_WAITQUEUE(wait, current);
982         struct sync_port *port;
983         int trunc_count;
984         unsigned long flags;
985         int bytes_free;
986         int out_buf_count;
987
988         unsigned char *rd_ptr;       /* First allocated byte in the buffer */
989         unsigned char *wr_ptr;       /* First free byte in the buffer */
990         unsigned char *buf_stop_ptr; /* Last byte + 1 */
991
992         if (dev < 0 || dev >= NBR_PORTS || !ports[dev].enabled) {
993                 DEBUG(printk("Invalid minor %d\n", dev));
994                 return -ENODEV;
995         }
996         port = &ports[dev];
997
998         /* |<-         OUT_BUFFER_SIZE                          ->|
999          *           |<- out_buf_count ->|
1000          *                               |<- trunc_count ->| ...->|
1001          *  ______________________________________________________
1002          * |  free   |   data            | free                   |
1003          * |_________|___________________|________________________|
1004          *           ^ rd_ptr            ^ wr_ptr
1005          */
1006         DEBUGWRITE(printk(KERN_DEBUG "W d%d c %lu a: %p c: %p\n",
1007                           port->port_nbr, count, port->active_tr_descr,
1008                           port->catch_tr_descr));
1009
1010         /* Read variables that may be updated by interrupts */
1011         spin_lock_irqsave(&port->lock, flags);
1012         rd_ptr = port->out_rd_ptr;
1013         out_buf_count = port->out_buf_count;
1014         spin_unlock_irqrestore(&port->lock, flags);
1015
1016         /* Check if resources are available */
1017         if (port->tr_running &&
1018             ((port->use_dma && port->active_tr_descr == port->catch_tr_descr) ||
1019              out_buf_count >= OUT_BUFFER_SIZE)) {
1020                 DEBUGWRITE(printk(KERN_DEBUG "sser%d full\n", dev));
1021                 return -EAGAIN;
1022         }
1023
1024         buf_stop_ptr = port->out_buffer + OUT_BUFFER_SIZE;
1025
1026         /* Determine pointer to the first free byte, before copying. */
1027         wr_ptr = rd_ptr + out_buf_count;
1028         if (wr_ptr >= buf_stop_ptr)
1029                 wr_ptr -= OUT_BUFFER_SIZE;
1030
1031         /* If we wrap the ring buffer, let the user space program handle it by
1032          * truncating the data. This could be more elegant, small buffer
1033          * fragments may occur.
1034          */
1035         bytes_free = OUT_BUFFER_SIZE - out_buf_count;
1036         if (wr_ptr + bytes_free > buf_stop_ptr)
1037                 bytes_free = buf_stop_ptr - wr_ptr;
1038         trunc_count = (count < bytes_free) ? count : bytes_free;
1039
1040         if (copy_from_user(wr_ptr, buf, trunc_count))
1041                 return -EFAULT;
1042
1043         DEBUGOUTBUF(printk(KERN_DEBUG "%-4d + %-4d = %-4d     %p %p %p\n",
1044                            out_buf_count, trunc_count,
1045                            port->out_buf_count, port->out_buffer,
1046                            wr_ptr, buf_stop_ptr));
1047
1048         /* Make sure transmitter/receiver is running */
1049         if (!port->started) {
1050                 reg_sser_rw_cfg cfg = REG_RD(sser, port->regi_sser, rw_cfg);
1051                 reg_sser_rw_rec_cfg rec_cfg = REG_RD(sser, port->regi_sser, rw_rec_cfg);
1052                 cfg.en = regk_sser_yes;
1053                 rec_cfg.rec_en = port->input;
1054                 REG_WR(sser, port->regi_sser, rw_cfg, cfg);
1055                 REG_WR(sser, port->regi_sser, rw_rec_cfg, rec_cfg);
1056                 port->started = 1;
1057         }
1058
1059         /* Setup wait if blocking */
1060         if (!(file->f_flags & O_NONBLOCK)) {
1061                 add_wait_queue(&port->out_wait_q, &wait);
1062                 set_current_state(TASK_INTERRUPTIBLE);
1063         }
1064
1065         spin_lock_irqsave(&port->lock, flags);
1066         port->out_buf_count += trunc_count;
1067         if (port->use_dma) {
1068                 start_dma_out(port, wr_ptr, trunc_count);
1069         } else if (!port->tr_running) {
1070                 reg_sser_rw_intr_mask intr_mask;
1071                 intr_mask = REG_RD(sser, port->regi_sser, rw_intr_mask);
1072                 /* Start sender by writing data */
1073                 send_word(port);
1074                 /* and enable transmitter ready IRQ */
1075                 intr_mask.trdy = 1;
1076                 REG_WR(sser, port->regi_sser, rw_intr_mask, intr_mask);
1077         }
1078         spin_unlock_irqrestore(&port->lock, flags);
1079
1080         /* Exit if non blocking */
1081         if (file->f_flags & O_NONBLOCK) {
1082                 DEBUGWRITE(printk(KERN_DEBUG "w d%d c %lu  %08x\n",
1083                                   port->port_nbr, trunc_count,
1084                                   REG_RD_INT(dma, port->regi_dmaout, r_intr)));
1085                 return trunc_count;
1086         }
1087
1088         schedule();
1089         set_current_state(TASK_RUNNING);
1090         remove_wait_queue(&port->out_wait_q, &wait);
1091
1092         if (signal_pending(current))
1093                 return -EINTR;
1094
1095         DEBUGWRITE(printk(KERN_DEBUG "w d%d c %lu\n",
1096                           port->port_nbr, trunc_count));
1097         return trunc_count;
1098 }
1099
1100 static ssize_t sync_serial_read(struct file * file, char * buf,
1101                                 size_t count, loff_t *ppos)
1102 {
1103         int dev = iminor(file->f_path.dentry->d_inode);
1104         int avail;
1105         sync_port *port;
1106         unsigned char* start;
1107         unsigned char* end;
1108         unsigned long flags;
1109
1110         if (dev < 0 || dev >= NBR_PORTS || !ports[dev].enabled)
1111         {
1112                 DEBUG(printk("Invalid minor %d\n", dev));
1113                 return -ENODEV;
1114         }
1115         port = &ports[dev];
1116
1117         DEBUGREAD(printk("R%d c %d ri %lu wi %lu /%lu\n", dev, count, port->readp - port->flip, port->writep - port->flip, port->in_buffer_size));
1118
1119         if (!port->started)
1120         {
1121                 reg_sser_rw_cfg cfg = REG_RD(sser, port->regi_sser, rw_cfg);
1122                 reg_sser_rw_tr_cfg tr_cfg = REG_RD(sser, port->regi_sser, rw_tr_cfg);
1123                 reg_sser_rw_rec_cfg rec_cfg = REG_RD(sser, port->regi_sser, rw_rec_cfg);
1124                 cfg.en = regk_sser_yes;
1125                 tr_cfg.tr_en = regk_sser_yes;
1126                 rec_cfg.rec_en = regk_sser_yes;
1127                 REG_WR(sser, port->regi_sser, rw_cfg, cfg);
1128                 REG_WR(sser, port->regi_sser, rw_tr_cfg, tr_cfg);
1129                 REG_WR(sser, port->regi_sser, rw_rec_cfg, rec_cfg);
1130                 port->started = 1;
1131         }
1132
1133         /* Calculate number of available bytes */
1134         /* Save pointers to avoid that they are modified by interrupt */
1135         spin_lock_irqsave(&port->lock, flags);
1136         start = (unsigned char*)port->readp; /* cast away volatile */
1137         end = (unsigned char*)port->writep;  /* cast away volatile */
1138         spin_unlock_irqrestore(&port->lock, flags);
1139         while ((start == end) && !port->full) /* No data */
1140         {
1141                 DEBUGREAD(printk(KERN_DEBUG "&"));
1142                 if (file->f_flags & O_NONBLOCK)
1143                         return -EAGAIN;
1144
1145                 interruptible_sleep_on(&port->in_wait_q);
1146                 if (signal_pending(current))
1147                         return -EINTR;
1148
1149                 spin_lock_irqsave(&port->lock, flags);
1150                 start = (unsigned char*)port->readp; /* cast away volatile */
1151                 end = (unsigned char*)port->writep;  /* cast away volatile */
1152                 spin_unlock_irqrestore(&port->lock, flags);
1153         }
1154
1155         /* Lazy read, never return wrapped data. */
1156         if (port->full)
1157                 avail = port->in_buffer_size;
1158         else if (end > start)
1159                 avail = end - start;
1160         else
1161                 avail = port->flip + port->in_buffer_size - start;
1162
1163         count = count > avail ? avail : count;
1164         if (copy_to_user(buf, start, count))
1165                 return -EFAULT;
1166         /* Disable interrupts while updating readp */
1167         spin_lock_irqsave(&port->lock, flags);
1168         port->readp += count;
1169         if (port->readp >= port->flip + port->in_buffer_size) /* Wrap? */
1170                 port->readp = port->flip;
1171         port->full = 0;
1172         spin_unlock_irqrestore(&port->lock, flags);
1173         DEBUGREAD(printk("r %d\n", count));
1174         return count;
1175 }
1176
1177 static void send_word(sync_port* port)
1178 {
1179         reg_sser_rw_tr_cfg tr_cfg = REG_RD(sser, port->regi_sser, rw_tr_cfg);
1180         reg_sser_rw_tr_data tr_data =  {0};
1181
1182         switch(tr_cfg.sample_size)
1183         {
1184          case 8:
1185                  port->out_buf_count--;
1186                  tr_data.data = *port->out_rd_ptr++;
1187                  REG_WR(sser, port->regi_sser, rw_tr_data, tr_data);
1188                  if (port->out_rd_ptr >= port->out_buffer + OUT_BUFFER_SIZE)
1189                          port->out_rd_ptr = port->out_buffer;
1190                  break;
1191          case 12:
1192          {
1193                 int data = (*port->out_rd_ptr++) << 8;
1194                 data |= *port->out_rd_ptr++;
1195                 port->out_buf_count -= 2;
1196                 tr_data.data = data;
1197                 REG_WR(sser, port->regi_sser, rw_tr_data, tr_data);
1198                 if (port->out_rd_ptr >= port->out_buffer + OUT_BUFFER_SIZE)
1199                         port->out_rd_ptr = port->out_buffer;
1200         }
1201         break;
1202         case 16:
1203                 port->out_buf_count -= 2;
1204                 tr_data.data = *(unsigned short *)port->out_rd_ptr;
1205                 REG_WR(sser, port->regi_sser, rw_tr_data, tr_data);
1206                 port->out_rd_ptr += 2;
1207                 if (port->out_rd_ptr >= port->out_buffer + OUT_BUFFER_SIZE)
1208                         port->out_rd_ptr = port->out_buffer;
1209                 break;
1210         case 24:
1211                 port->out_buf_count -= 3;
1212                 tr_data.data = *(unsigned short *)port->out_rd_ptr;
1213                 REG_WR(sser, port->regi_sser, rw_tr_data, tr_data);
1214                 port->out_rd_ptr += 2;
1215                 tr_data.data = *port->out_rd_ptr++;
1216                 REG_WR(sser, port->regi_sser, rw_tr_data, tr_data);
1217                 if (port->out_rd_ptr >= port->out_buffer + OUT_BUFFER_SIZE)
1218                         port->out_rd_ptr = port->out_buffer;
1219                 break;
1220         case 32:
1221                 port->out_buf_count -= 4;
1222                 tr_data.data = *(unsigned short *)port->out_rd_ptr;
1223                 REG_WR(sser, port->regi_sser, rw_tr_data, tr_data);
1224                 port->out_rd_ptr += 2;
1225                 tr_data.data = *(unsigned short *)port->out_rd_ptr;
1226                 REG_WR(sser, port->regi_sser, rw_tr_data, tr_data);
1227                 port->out_rd_ptr += 2;
1228                 if (port->out_rd_ptr >= port->out_buffer + OUT_BUFFER_SIZE)
1229                         port->out_rd_ptr = port->out_buffer;
1230                 break;
1231         }
1232 }
1233
1234 static void start_dma_out(struct sync_port *port,
1235                           const char *data, int count)
1236 {
1237         port->active_tr_descr->buf = (char *) virt_to_phys((char *) data);
1238         port->active_tr_descr->after = port->active_tr_descr->buf + count;
1239         port->active_tr_descr->intr = 1;
1240
1241         port->active_tr_descr->eol = 1;
1242         port->prev_tr_descr->eol = 0;
1243
1244         DEBUGTRDMA(printk(KERN_DEBUG "Inserting eolr:%p eol@:%p\n",
1245                 port->prev_tr_descr, port->active_tr_descr));
1246         port->prev_tr_descr = port->active_tr_descr;
1247         port->active_tr_descr = phys_to_virt((int) port->active_tr_descr->next);
1248
1249         if (!port->tr_running) {
1250                 reg_sser_rw_tr_cfg tr_cfg = REG_RD(sser, port->regi_sser,
1251                         rw_tr_cfg);
1252
1253                 port->out_context.next = 0;
1254                 port->out_context.saved_data =
1255                         (dma_descr_data *)virt_to_phys(port->prev_tr_descr);
1256                 port->out_context.saved_data_buf = port->prev_tr_descr->buf;
1257
1258                 DMA_START_CONTEXT(port->regi_dmaout,
1259                         virt_to_phys((char *)&port->out_context));
1260
1261                 tr_cfg.tr_en = regk_sser_yes;
1262                 REG_WR(sser, port->regi_sser, rw_tr_cfg, tr_cfg);
1263                 DEBUGTRDMA(printk(KERN_DEBUG "dma s\n"););
1264         } else {
1265                 DMA_CONTINUE_DATA(port->regi_dmaout);
1266                 DEBUGTRDMA(printk(KERN_DEBUG "dma c\n"););
1267         }
1268
1269         port->tr_running = 1;
1270 }
1271
1272 static void start_dma_in(sync_port *port)
1273 {
1274         int i;
1275         char *buf;
1276         port->writep = port->flip;
1277
1278         if (port->writep > port->flip + port->in_buffer_size) {
1279                 panic("Offset too large in sync serial driver\n");
1280                 return;
1281         }
1282         buf = (char*)virt_to_phys(port->in_buffer);
1283         for (i = 0; i < NBR_IN_DESCR; i++) {
1284                 port->in_descr[i].buf = buf;
1285                 port->in_descr[i].after = buf + port->inbufchunk;
1286                 port->in_descr[i].intr = 1;
1287                 port->in_descr[i].next = (dma_descr_data*)virt_to_phys(&port->in_descr[i+1]);
1288                 port->in_descr[i].buf = buf;
1289                 buf += port->inbufchunk;
1290         }
1291         /* Link the last descriptor to the first */
1292         port->in_descr[i-1].next = (dma_descr_data*)virt_to_phys(&port->in_descr[0]);
1293         port->in_descr[i-1].eol = regk_sser_yes;
1294         port->next_rx_desc = &port->in_descr[0];
1295         port->prev_rx_desc = &port->in_descr[NBR_IN_DESCR - 1];
1296         port->in_context.saved_data = (dma_descr_data*)virt_to_phys(&port->in_descr[0]);
1297         port->in_context.saved_data_buf = port->in_descr[0].buf;
1298         DMA_START_CONTEXT(port->regi_dmain, virt_to_phys(&port->in_context));
1299 }
1300
1301 #ifdef SYNC_SER_DMA
1302 static irqreturn_t tr_interrupt(int irq, void *dev_id)
1303 {
1304         reg_dma_r_masked_intr masked;
1305         reg_dma_rw_ack_intr ack_intr = {.data = regk_dma_yes};
1306         reg_dma_rw_stat stat;
1307         int i;
1308         int found = 0;
1309         int stop_sser = 0;
1310
1311         for (i = 0; i < NBR_PORTS; i++) {
1312                 sync_port *port = &ports[i];
1313                 if (!port->enabled  || !port->use_dma)
1314                         continue;
1315
1316                 /* IRQ active for the port? */
1317                 masked = REG_RD(dma, port->regi_dmaout, r_masked_intr);
1318                 if (!masked.data)
1319                         continue;
1320
1321                 found = 1;
1322
1323                 /* Check if we should stop the DMA transfer */
1324                 stat = REG_RD(dma, port->regi_dmaout, rw_stat);
1325                 if (stat.list_state == regk_dma_data_at_eol)
1326                         stop_sser = 1;
1327
1328                 /* Clear IRQ */
1329                 REG_WR(dma, port->regi_dmaout, rw_ack_intr, ack_intr);
1330
1331                 if (!stop_sser) {
1332                         /* The DMA has completed a descriptor, EOL was not
1333                          * encountered, so step relevant descriptor and
1334                          * datapointers forward. */
1335                         int sent;
1336                         sent = port->catch_tr_descr->after -
1337                                 port->catch_tr_descr->buf;
1338                         DEBUGTXINT(printk(KERN_DEBUG "%-4d - %-4d = %-4d\t"
1339                                           "in descr %p (ac: %p)\n",
1340                                           port->out_buf_count, sent,
1341                                           port->out_buf_count - sent,
1342                                           port->catch_tr_descr,
1343                                           port->active_tr_descr););
1344                         port->out_buf_count -= sent;
1345                         port->catch_tr_descr =
1346                                 phys_to_virt((int) port->catch_tr_descr->next);
1347                         port->out_rd_ptr =
1348                                 phys_to_virt((int) port->catch_tr_descr->buf);
1349                 } else {
1350                         int i, sent;
1351                         /* EOL handler.
1352                          * Note that if an EOL was encountered during the irq
1353                          * locked section of sync_ser_write the DMA will be
1354                          * restarted and the eol flag will be cleared.
1355                          * The remaining descriptors will be traversed by
1356                          * the descriptor interrupts as usual.
1357                          */
1358                         i = 0;
1359                         while (!port->catch_tr_descr->eol) {
1360                                 sent = port->catch_tr_descr->after -
1361                                         port->catch_tr_descr->buf;
1362                                 DEBUGOUTBUF(printk(KERN_DEBUG
1363                                         "traversing descr %p -%d (%d)\n",
1364                                         port->catch_tr_descr,
1365                                         sent,
1366                                         port->out_buf_count));
1367                                 port->out_buf_count -= sent;
1368                                 port->catch_tr_descr = phys_to_virt(
1369                                         (int)port->catch_tr_descr->next);
1370                                 i++;
1371                                 if (i >= NBR_OUT_DESCR) {
1372                                         /* TODO: Reset and recover */
1373                                         panic("sync_serial: missing eol");
1374                                 }
1375                         }
1376                         sent = port->catch_tr_descr->after -
1377                                 port->catch_tr_descr->buf;
1378                         DEBUGOUTBUF(printk(KERN_DEBUG
1379                                 "eol at descr %p -%d (%d)\n",
1380                                 port->catch_tr_descr,
1381                                 sent,
1382                                 port->out_buf_count));
1383
1384                         port->out_buf_count -= sent;
1385
1386                         /* Update read pointer to first free byte, we
1387                          * may already be writing data there. */
1388                         port->out_rd_ptr =
1389                                 phys_to_virt((int) port->catch_tr_descr->after);
1390                         if (port->out_rd_ptr > port->out_buffer +
1391                                         OUT_BUFFER_SIZE)
1392                                 port->out_rd_ptr = port->out_buffer;
1393
1394                         reg_sser_rw_tr_cfg tr_cfg =
1395                                 REG_RD(sser, port->regi_sser, rw_tr_cfg);
1396                         DEBUGTXINT(printk(KERN_DEBUG
1397                                 "tr_int DMA stop %d, set catch @ %p\n",
1398                                 port->out_buf_count,
1399                                 port->active_tr_descr));
1400                         if (port->out_buf_count != 0)
1401                                 printk(KERN_CRIT "sync_ser: buffer not "
1402                                         "empty after eol.\n");
1403                         port->catch_tr_descr = port->active_tr_descr;
1404                         port->tr_running = 0;
1405                         tr_cfg.tr_en = regk_sser_no;
1406                         REG_WR(sser, port->regi_sser, rw_tr_cfg, tr_cfg);
1407                 }
1408                 /* wake up the waiting process */
1409                 wake_up_interruptible(&port->out_wait_q);
1410         }
1411         return IRQ_RETVAL(found);
1412 } /* tr_interrupt */
1413
1414 static irqreturn_t rx_interrupt(int irq, void *dev_id)
1415 {
1416         reg_dma_r_masked_intr masked;
1417         reg_dma_rw_ack_intr ack_intr = {.data = regk_dma_yes};
1418
1419         int i;
1420         int found = 0;
1421
1422         for (i = 0; i < NBR_PORTS; i++)
1423         {
1424                 sync_port *port = &ports[i];
1425
1426                 if (!port->enabled || !port->use_dma )
1427                         continue;
1428
1429                 masked = REG_RD(dma, port->regi_dmain, r_masked_intr);
1430
1431                 if (masked.data) /* Descriptor interrupt */
1432                 {
1433                         found = 1;
1434                         while (REG_RD(dma, port->regi_dmain, rw_data) !=
1435                                virt_to_phys(port->next_rx_desc)) {
1436                                 DEBUGRXINT(printk(KERN_DEBUG "!"));
1437                                 if (port->writep + port->inbufchunk > port->flip + port->in_buffer_size) {
1438                                         int first_size = port->flip + port->in_buffer_size - port->writep;
1439                                         memcpy((char*)port->writep, phys_to_virt((unsigned)port->next_rx_desc->buf), first_size);
1440                                         memcpy(port->flip, phys_to_virt((unsigned)port->next_rx_desc->buf+first_size), port->inbufchunk - first_size);
1441                                         port->writep = port->flip + port->inbufchunk - first_size;
1442                                 } else {
1443                                         memcpy((char*)port->writep,
1444                                                phys_to_virt((unsigned)port->next_rx_desc->buf),
1445                                                port->inbufchunk);
1446                                         port->writep += port->inbufchunk;
1447                                         if (port->writep >= port->flip + port->in_buffer_size)
1448                                                 port->writep = port->flip;
1449                                 }
1450                                 if (port->writep == port->readp)
1451                                 {
1452                                   port->full = 1;
1453                                 }
1454
1455                                 port->next_rx_desc->eol = 1;
1456                                 port->prev_rx_desc->eol = 0;
1457                                 /* Cache bug workaround */
1458                                 flush_dma_descr(port->prev_rx_desc, 0);
1459                                 port->prev_rx_desc = port->next_rx_desc;
1460                                 port->next_rx_desc = phys_to_virt((unsigned)port->next_rx_desc->next);
1461                                 /* Cache bug workaround */
1462                                 flush_dma_descr(port->prev_rx_desc, 1);
1463                                 /* wake up the waiting process */
1464                                 wake_up_interruptible(&port->in_wait_q);
1465                                 DMA_CONTINUE(port->regi_dmain);
1466                                 REG_WR(dma, port->regi_dmain, rw_ack_intr, ack_intr);
1467
1468                         }
1469                 }
1470         }
1471         return IRQ_RETVAL(found);
1472 } /* rx_interrupt */
1473 #endif /* SYNC_SER_DMA */
1474
1475 #ifdef SYNC_SER_MANUAL
1476 static irqreturn_t manual_interrupt(int irq, void *dev_id)
1477 {
1478         int i;
1479         int found = 0;
1480         reg_sser_r_masked_intr masked;
1481
1482         for (i = 0; i < NBR_PORTS; i++)
1483         {
1484                 sync_port *port = &ports[i];
1485
1486                 if (!port->enabled || port->use_dma)
1487                 {
1488                         continue;
1489                 }
1490
1491                 masked = REG_RD(sser, port->regi_sser, r_masked_intr);
1492                 if (masked.rdav)        /* Data received? */
1493                 {
1494                         reg_sser_rw_rec_cfg rec_cfg = REG_RD(sser, port->regi_sser, rw_rec_cfg);
1495                         reg_sser_r_rec_data data = REG_RD(sser, port->regi_sser, r_rec_data);
1496                         found = 1;
1497                         /* Read data */
1498                         switch(rec_cfg.sample_size)
1499                         {
1500                         case 8:
1501                                 *port->writep++ = data.data & 0xff;
1502                                 break;
1503                         case 12:
1504                                 *port->writep = (data.data & 0x0ff0) >> 4;
1505                                 *(port->writep + 1) = data.data & 0x0f;
1506                                 port->writep+=2;
1507                                 break;
1508                         case 16:
1509                                 *(unsigned short*)port->writep = data.data;
1510                                 port->writep+=2;
1511                                 break;
1512                         case 24:
1513                                 *(unsigned int*)port->writep = data.data;
1514                                 port->writep+=3;
1515                                 break;
1516                         case 32:
1517                                 *(unsigned int*)port->writep = data.data;
1518                                 port->writep+=4;
1519                                 break;
1520                         }
1521
1522                         if (port->writep >= port->flip + port->in_buffer_size) /* Wrap? */
1523                                 port->writep = port->flip;
1524                         if (port->writep == port->readp) {
1525                                 /* receive buffer overrun, discard oldest data
1526                                  */
1527                                 port->readp++;
1528                                 if (port->readp >= port->flip + port->in_buffer_size) /* Wrap? */
1529                                         port->readp = port->flip;
1530                         }
1531                         if (sync_data_avail(port) >= port->inbufchunk)
1532                                 wake_up_interruptible(&port->in_wait_q); /* Wake up application */
1533                 }
1534
1535                 if (masked.trdy) /* Transmitter ready? */
1536                 {
1537                         found = 1;
1538                         if (port->out_buf_count > 0) /* More data to send */
1539                                 send_word(port);
1540                         else /* transmission finished */
1541                         {
1542                                 reg_sser_rw_intr_mask intr_mask;
1543                                 intr_mask = REG_RD(sser, port->regi_sser, rw_intr_mask);
1544                                 intr_mask.trdy = 0;
1545                                 REG_WR(sser, port->regi_sser, rw_intr_mask, intr_mask);
1546                                 wake_up_interruptible(&port->out_wait_q); /* Wake up application */
1547                         }
1548                 }
1549         }
1550         return IRQ_RETVAL(found);
1551 }
1552 #endif
1553
1554 module_init(etrax_sync_serial_init);