1/*
2 * Simple synchronous serial port driver for ETRAX 100LX.
3 *
4 * Synchronous serial ports are used for continuous streamed data like audio.
5 * The default setting for this driver is compatible with the STA 013 MP3
6 * decoder. The driver can easily be tuned to fit other audio encoder/decoders
7 * and SPI
8 *
9 * Copyright (c) 2001-2008 Axis Communications AB
10 *
11 * Author: Mikael Starvik, Johan Adolfsson
12 *
13 */
14#include <linux/module.h>
15#include <linux/kernel.h>
16#include <linux/types.h>
17#include <linux/errno.h>
18#include <linux/major.h>
19#include <linux/sched.h>
20#include <linux/interrupt.h>
21#include <linux/poll.h>
22#include <linux/init.h>
23#include <linux/mutex.h>
24#include <linux/timer.h>
25#include <linux/wait.h>
26#include <asm/irq.h>
27#include <asm/dma.h>
28#include <asm/io.h>
29#include <arch/svinto.h>
30#include <asm/uaccess.h>
31#include <asm/sync_serial.h>
32#include <arch/io_interface_mux.h>
33
34/* The receiver is a bit tricky because of the continuous stream of data.*/
35/*                                                                       */
36/* Three DMA descriptors are linked together. Each DMA descriptor is     */
37/* responsible for port->bufchunk of a common buffer.                    */
38/*                                                                       */
39/* +---------------------------------------------+                       */
40/* |   +----------+   +----------+   +----------+ |                      */
41/* +-> | Descr[0] |-->| Descr[1] |-->| Descr[2] |-+                      */
42/*     +----------+   +----------+   +----------+                        */
43/*         |            |              |                                 */
44/*         v            v              v                                 */
45/*   +-------------------------------------+                             */
46/*   |        BUFFER                       |                             */
47/*   +-------------------------------------+                             */
48/*      |<- data_avail ->|                                               */
49/*    readp          writep                                              */
50/*                                                                       */
51/* If the application keeps up the pace readp will be right after writep.*/
52/* If the application can't keep the pace we have to throw away data.    */
53/* The idea is that readp should be ready with the data pointed out by	 */
54/* Descr[i] when the DMA has filled in Descr[i+1].                       */
55/* Otherwise we will discard	                                         */
56/* the rest of the data pointed out by Descr1 and set readp to the start */
57/* of Descr2                                                             */
58
59#define SYNC_SERIAL_MAJOR 125
60
61/* IN_BUFFER_SIZE should be a multiple of 6 to make sure that 24 bit */
62/* words can be handled */
63#define IN_BUFFER_SIZE 12288
64#define IN_DESCR_SIZE 256
65#define NUM_IN_DESCR (IN_BUFFER_SIZE/IN_DESCR_SIZE)
66#define OUT_BUFFER_SIZE 4096
67
68#define DEFAULT_FRAME_RATE 0
69#define DEFAULT_WORD_RATE 7
70
71/* NOTE: Enabling some debug will likely cause overrun or underrun,
72 * especially if manual mode is use.
73 */
74#define DEBUG(x)
75#define DEBUGREAD(x)
76#define DEBUGWRITE(x)
77#define DEBUGPOLL(x)
78#define DEBUGRXINT(x)
79#define DEBUGTXINT(x)
80
81/* Define some macros to access ETRAX 100 registers */
82#define SETF(var, reg, field, val) \
83	do { \
84		var = (var & ~IO_MASK_(reg##_, field##_)) | \
85			IO_FIELD_(reg##_, field##_, val); \
86	} while (0)
87
88#define SETS(var, reg, field, val) \
89	do { \
90		var = (var & ~IO_MASK_(reg##_, field##_)) | \
91			IO_STATE_(reg##_, field##_, _##val); \
92	} while (0)
93
94struct sync_port {
95	/* Etrax registers and bits*/
96	const volatile unsigned *const status;
97	volatile unsigned *const ctrl_data;
98	volatile unsigned *const output_dma_first;
99	volatile unsigned char *const output_dma_cmd;
100	volatile unsigned char *const output_dma_clr_irq;
101	volatile unsigned *const input_dma_first;
102	volatile unsigned char *const input_dma_cmd;
103	volatile unsigned *const input_dma_descr;
104	/* 8*4 */
105	volatile unsigned char *const input_dma_clr_irq;
106	volatile unsigned *const data_out;
107	const volatile unsigned *const data_in;
108	char data_avail_bit; /* In R_IRQ_MASK1_RD/SET/CLR */
109	char transmitter_ready_bit; /* In R_IRQ_MASK1_RD/SET/CLR */
110	char input_dma_descr_bit; /* In R_IRQ_MASK2_RD */
111
112	char output_dma_bit; /* In R_IRQ_MASK2_RD */
113	/* End of fields initialised in array */
114	char started; /* 1 if port has been started */
115	char port_nbr; /* Port 0 or 1 */
116	char busy; /* 1 if port is busy */
117
118	char enabled;  /* 1 if port is enabled */
119	char use_dma;  /* 1 if port uses dma */
120	char tr_running;
121
122	char init_irqs;
123
124	/* Register shadow */
125	unsigned int ctrl_data_shadow;
126	/* Remaining bytes for current transfer */
127	volatile unsigned int out_count;
128	/* Current position in out_buffer */
129	unsigned char *outp;
130	/* 16*4 */
131	/* Next byte to be read by application */
132	volatile unsigned char *volatile readp;
133	/* Next byte to be written by etrax */
134	volatile unsigned char *volatile writep;
135
136	unsigned int in_buffer_size;
137	unsigned int inbufchunk;
138	struct etrax_dma_descr out_descr __attribute__ ((aligned(32)));
139	struct etrax_dma_descr in_descr[NUM_IN_DESCR] __attribute__ ((aligned(32)));
140	unsigned char out_buffer[OUT_BUFFER_SIZE] __attribute__ ((aligned(32)));
141	unsigned char in_buffer[IN_BUFFER_SIZE]__attribute__ ((aligned(32)));
142	unsigned char flip[IN_BUFFER_SIZE] __attribute__ ((aligned(32)));
143	struct etrax_dma_descr *next_rx_desc;
144	struct etrax_dma_descr *prev_rx_desc;
145	int full;
146
147	wait_queue_head_t out_wait_q;
148	wait_queue_head_t in_wait_q;
149};
150
151
152static DEFINE_MUTEX(sync_serial_mutex);
153static int etrax_sync_serial_init(void);
154static void initialize_port(int portnbr);
155static inline int sync_data_avail(struct sync_port *port);
156
157static int sync_serial_open(struct inode *inode, struct file *file);
158static int sync_serial_release(struct inode *inode, struct file *file);
159static unsigned int sync_serial_poll(struct file *filp, poll_table *wait);
160
161static long sync_serial_ioctl(struct file *file,
162	unsigned int cmd, unsigned long arg);
163static ssize_t sync_serial_write(struct file *file, const char *buf,
164	size_t count, loff_t *ppos);
165static ssize_t sync_serial_read(struct file *file, char *buf,
166	size_t count, loff_t *ppos);
167
168#if ((defined(CONFIG_ETRAX_SYNCHRONOUS_SERIAL_PORT0) && \
169     defined(CONFIG_ETRAX_SYNCHRONOUS_SERIAL0_DMA)) || \
170    (defined(CONFIG_ETRAX_SYNCHRONOUS_SERIAL_PORT1) && \
171     defined(CONFIG_ETRAX_SYNCHRONOUS_SERIAL1_DMA)))
172#define SYNC_SER_DMA
173#endif
174
175static void send_word(struct sync_port *port);
176static void start_dma(struct sync_port *port, const char *data, int count);
177static void start_dma_in(struct sync_port *port);
178#ifdef SYNC_SER_DMA
179static irqreturn_t tr_interrupt(int irq, void *dev_id);
180static irqreturn_t rx_interrupt(int irq, void *dev_id);
181#endif
182#if ((defined(CONFIG_ETRAX_SYNCHRONOUS_SERIAL_PORT0) && \
183     !defined(CONFIG_ETRAX_SYNCHRONOUS_SERIAL0_DMA)) || \
184    (defined(CONFIG_ETRAX_SYNCHRONOUS_SERIAL_PORT1) && \
185     !defined(CONFIG_ETRAX_SYNCHRONOUS_SERIAL1_DMA)))
186#define SYNC_SER_MANUAL
187#endif
188#ifdef SYNC_SER_MANUAL
189static irqreturn_t manual_interrupt(int irq, void *dev_id);
190#endif
191
192/* The ports */
193static struct sync_port ports[] = {
194	{
195		.status                = R_SYNC_SERIAL1_STATUS,
196		.ctrl_data             = R_SYNC_SERIAL1_CTRL,
197		.output_dma_first      = R_DMA_CH8_FIRST,
198		.output_dma_cmd        = R_DMA_CH8_CMD,
199		.output_dma_clr_irq    = R_DMA_CH8_CLR_INTR,
200		.input_dma_first       = R_DMA_CH9_FIRST,
201		.input_dma_cmd         = R_DMA_CH9_CMD,
202		.input_dma_descr       = R_DMA_CH9_DESCR,
203		.input_dma_clr_irq     = R_DMA_CH9_CLR_INTR,
204		.data_out              = R_SYNC_SERIAL1_TR_DATA,
205		.data_in               = R_SYNC_SERIAL1_REC_DATA,
206		.data_avail_bit        = IO_BITNR(R_IRQ_MASK1_RD, ser1_data),
207		.transmitter_ready_bit = IO_BITNR(R_IRQ_MASK1_RD, ser1_ready),
208		.input_dma_descr_bit   = IO_BITNR(R_IRQ_MASK2_RD, dma9_descr),
209		.output_dma_bit        = IO_BITNR(R_IRQ_MASK2_RD, dma8_eop),
210		.init_irqs             = 1,
211#if defined(CONFIG_ETRAX_SYNCHRONOUS_SERIAL0_DMA)
212		.use_dma               = 1,
213#else
214		.use_dma               = 0,
215#endif
216	},
217	{
218		.status                = R_SYNC_SERIAL3_STATUS,
219		.ctrl_data             = R_SYNC_SERIAL3_CTRL,
220		.output_dma_first      = R_DMA_CH4_FIRST,
221		.output_dma_cmd        = R_DMA_CH4_CMD,
222		.output_dma_clr_irq    = R_DMA_CH4_CLR_INTR,
223		.input_dma_first       = R_DMA_CH5_FIRST,
224		.input_dma_cmd         = R_DMA_CH5_CMD,
225		.input_dma_descr       = R_DMA_CH5_DESCR,
226		.input_dma_clr_irq     = R_DMA_CH5_CLR_INTR,
227		.data_out              = R_SYNC_SERIAL3_TR_DATA,
228		.data_in               = R_SYNC_SERIAL3_REC_DATA,
229		.data_avail_bit        = IO_BITNR(R_IRQ_MASK1_RD, ser3_data),
230		.transmitter_ready_bit = IO_BITNR(R_IRQ_MASK1_RD, ser3_ready),
231		.input_dma_descr_bit   = IO_BITNR(R_IRQ_MASK2_RD, dma5_descr),
232		.output_dma_bit        = IO_BITNR(R_IRQ_MASK2_RD, dma4_eop),
233		.init_irqs             = 1,
234#if defined(CONFIG_ETRAX_SYNCHRONOUS_SERIAL1_DMA)
235		.use_dma               = 1,
236#else
237		.use_dma               = 0,
238#endif
239	}
240};
241
242/* Register shadows */
243static unsigned sync_serial_prescale_shadow;
244
245#define NUMBER_OF_PORTS 2
246
247static const struct file_operations sync_serial_fops = {
248	.owner		= THIS_MODULE,
249	.write		= sync_serial_write,
250	.read		= sync_serial_read,
251	.poll		= sync_serial_poll,
252	.unlocked_ioctl	= sync_serial_ioctl,
253	.open		= sync_serial_open,
254	.release	= sync_serial_release,
255	.llseek		= noop_llseek,
256};
257
258static int __init etrax_sync_serial_init(void)
259{
260	ports[0].enabled = 0;
261	ports[1].enabled = 0;
262
263#if defined(CONFIG_ETRAX_SYNCHRONOUS_SERIAL_PORT0)
264	if (cris_request_io_interface(if_sync_serial_1, "sync_ser1")) {
265		printk(KERN_CRIT "ETRAX100LX sync_serial: "
266			"Could not allocate IO group for port %d\n", 0);
267		return -EBUSY;
268	}
269#endif
270#if defined(CONFIG_ETRAX_SYNCHRONOUS_SERIAL_PORT1)
271	if (cris_request_io_interface(if_sync_serial_3, "sync_ser3")) {
272#if defined(CONFIG_ETRAX_SYNCHRONOUS_SERIAL_PORT0)
273		cris_free_io_interface(if_sync_serial_1);
274#endif
275		printk(KERN_CRIT "ETRAX100LX sync_serial: "
276			"Could not allocate IO group for port %d\n", 1);
277		return -EBUSY;
278	}
279#endif
280
281	if (register_chrdev(SYNC_SERIAL_MAJOR, "sync serial",
282			&sync_serial_fops) < 0) {
283#if defined(CONFIG_ETRAX_SYNCHRONOUS_SERIAL_PORT1)
284		cris_free_io_interface(if_sync_serial_3);
285#endif
286#if defined(CONFIG_ETRAX_SYNCHRONOUS_SERIAL_PORT0)
287		cris_free_io_interface(if_sync_serial_1);
288#endif
289		printk("unable to get major for synchronous serial port\n");
290		return -EBUSY;
291	}
292
293	/* Deselect synchronous serial ports while configuring. */
294	SETS(gen_config_ii_shadow, R_GEN_CONFIG_II, sermode1, async);
295	SETS(gen_config_ii_shadow, R_GEN_CONFIG_II, sermode3, async);
296	*R_GEN_CONFIG_II = gen_config_ii_shadow;
297
298	/* Initialize Ports */
299#if defined(CONFIG_ETRAX_SYNCHRONOUS_SERIAL_PORT0)
300	ports[0].enabled = 1;
301	SETS(port_pb_i2c_shadow, R_PORT_PB_I2C, syncser1, ss1extra);
302	SETS(gen_config_ii_shadow, R_GEN_CONFIG_II, sermode1, sync);
303#if defined(CONFIG_ETRAX_SYNCHRONOUS_SERIAL0_DMA)
304	ports[0].use_dma = 1;
305#else
306	ports[0].use_dma = 0;
307#endif
308	initialize_port(0);
309#endif
310
311#if defined(CONFIG_ETRAX_SYNCHRONOUS_SERIAL_PORT1)
312	ports[1].enabled = 1;
313	SETS(port_pb_i2c_shadow, R_PORT_PB_I2C, syncser3, ss3extra);
314	SETS(gen_config_ii_shadow, R_GEN_CONFIG_II, sermode3, sync);
315#if defined(CONFIG_ETRAX_SYNCHRONOUS_SERIAL1_DMA)
316	ports[1].use_dma = 1;
317#else
318	ports[1].use_dma = 0;
319#endif
320	initialize_port(1);
321#endif
322
323	*R_PORT_PB_I2C = port_pb_i2c_shadow; /* Use PB4/PB7 */
324
325	/* Set up timing */
326	*R_SYNC_SERIAL_PRESCALE = sync_serial_prescale_shadow = (
327		IO_STATE(R_SYNC_SERIAL_PRESCALE, clk_sel_u1, codec) |
328		IO_STATE(R_SYNC_SERIAL_PRESCALE, word_stb_sel_u1, external) |
329		IO_STATE(R_SYNC_SERIAL_PRESCALE, clk_sel_u3, codec) |
330		IO_STATE(R_SYNC_SERIAL_PRESCALE, word_stb_sel_u3, external) |
331		IO_STATE(R_SYNC_SERIAL_PRESCALE, prescaler, div4) |
332		IO_FIELD(R_SYNC_SERIAL_PRESCALE, frame_rate,
333			DEFAULT_FRAME_RATE) |
334		IO_FIELD(R_SYNC_SERIAL_PRESCALE, word_rate, DEFAULT_WORD_RATE) |
335		IO_STATE(R_SYNC_SERIAL_PRESCALE, warp_mode, normal));
336
337	/* Select synchronous ports */
338	*R_GEN_CONFIG_II = gen_config_ii_shadow;
339
340	printk(KERN_INFO "ETRAX 100LX synchronous serial port driver\n");
341	return 0;
342}
343
344static void __init initialize_port(int portnbr)
345{
346	struct sync_port *port = &ports[portnbr];
347
348	DEBUG(printk(KERN_DEBUG "Init sync serial port %d\n", portnbr));
349
350	port->started = 0;
351	port->port_nbr = portnbr;
352	port->busy = 0;
353	port->tr_running = 0;
354
355	port->out_count = 0;
356	port->outp = port->out_buffer;
357
358	port->readp = port->flip;
359	port->writep = port->flip;
360	port->in_buffer_size = IN_BUFFER_SIZE;
361	port->inbufchunk = IN_DESCR_SIZE;
362	port->next_rx_desc = &port->in_descr[0];
363	port->prev_rx_desc = &port->in_descr[NUM_IN_DESCR-1];
364	port->prev_rx_desc->ctrl = d_eol;
365
366	init_waitqueue_head(&port->out_wait_q);
367	init_waitqueue_head(&port->in_wait_q);
368
369	port->ctrl_data_shadow =
370		IO_STATE(R_SYNC_SERIAL1_CTRL, tr_baud, c115k2Hz)   |
371		IO_STATE(R_SYNC_SERIAL1_CTRL, mode, master_output) |
372		IO_STATE(R_SYNC_SERIAL1_CTRL, error, ignore)       |
373		IO_STATE(R_SYNC_SERIAL1_CTRL, rec_enable, disable) |
374		IO_STATE(R_SYNC_SERIAL1_CTRL, f_synctype, normal)  |
375		IO_STATE(R_SYNC_SERIAL1_CTRL, f_syncsize, word)    |
376		IO_STATE(R_SYNC_SERIAL1_CTRL, f_sync, on)	     |
377		IO_STATE(R_SYNC_SERIAL1_CTRL, clk_mode, normal)    |
378		IO_STATE(R_SYNC_SERIAL1_CTRL, clk_halt, stopped)   |
379		IO_STATE(R_SYNC_SERIAL1_CTRL, bitorder, msb)	     |
380		IO_STATE(R_SYNC_SERIAL1_CTRL, tr_enable, disable)  |
381		IO_STATE(R_SYNC_SERIAL1_CTRL, wordsize, size8bit)  |
382		IO_STATE(R_SYNC_SERIAL1_CTRL, buf_empty, lmt_8)    |
383		IO_STATE(R_SYNC_SERIAL1_CTRL, buf_full, lmt_8)     |
384		IO_STATE(R_SYNC_SERIAL1_CTRL, flow_ctrl, enabled)  |
385		IO_STATE(R_SYNC_SERIAL1_CTRL, clk_polarity, neg)   |
386		IO_STATE(R_SYNC_SERIAL1_CTRL, frame_polarity, normal)|
387		IO_STATE(R_SYNC_SERIAL1_CTRL, status_polarity, inverted)|
388		IO_STATE(R_SYNC_SERIAL1_CTRL, clk_driver, normal)   |
389		IO_STATE(R_SYNC_SERIAL1_CTRL, frame_driver, normal) |
390		IO_STATE(R_SYNC_SERIAL1_CTRL, status_driver, normal)|
391		IO_STATE(R_SYNC_SERIAL1_CTRL, def_out0, high);
392
393	if (port->use_dma)
394		port->ctrl_data_shadow |= IO_STATE(R_SYNC_SERIAL1_CTRL,
395			dma_enable, on);
396	else
397		port->ctrl_data_shadow |= IO_STATE(R_SYNC_SERIAL1_CTRL,
398			dma_enable, off);
399
400	*port->ctrl_data = port->ctrl_data_shadow;
401}
402
403static inline int sync_data_avail(struct sync_port *port)
404{
405	int avail;
406	unsigned char *start;
407	unsigned char *end;
408
409	start = (unsigned char *)port->readp; /* cast away volatile */
410	end = (unsigned char *)port->writep;  /* cast away volatile */
411	/* 0123456789  0123456789
412	 *  -----      -    -----
413	 *  ^rp  ^wp    ^wp ^rp
414	 */
415	if (end >= start)
416		avail = end - start;
417	else
418		avail = port->in_buffer_size - (start - end);
419	return avail;
420}
421
422static inline int sync_data_avail_to_end(struct sync_port *port)
423{
424	int avail;
425	unsigned char *start;
426	unsigned char *end;
427
428	start = (unsigned char *)port->readp; /* cast away volatile */
429	end = (unsigned char *)port->writep;  /* cast away volatile */
430	/* 0123456789  0123456789
431	 *  -----           -----
432	 *  ^rp  ^wp    ^wp ^rp
433	 */
434
435	if (end >= start)
436		avail = end - start;
437	else
438		avail = port->flip + port->in_buffer_size - start;
439	return avail;
440}
441
442
443static int sync_serial_open(struct inode *inode, struct file *file)
444{
445	int dev = MINOR(inode->i_rdev);
446	struct sync_port *port;
447	int mode;
448	int err = -EBUSY;
449
450	mutex_lock(&sync_serial_mutex);
451	DEBUG(printk(KERN_DEBUG "Open sync serial port %d\n", dev));
452
453	if (dev < 0 || dev >= NUMBER_OF_PORTS || !ports[dev].enabled) {
454		DEBUG(printk(KERN_DEBUG "Invalid minor %d\n", dev));
455		err = -ENODEV;
456		goto out;
457	}
458	port = &ports[dev];
459	/* Allow open this device twice (assuming one reader and one writer) */
460	if (port->busy == 2) {
461		DEBUG(printk(KERN_DEBUG "Device is busy.. \n"));
462		goto out;
463	}
464	if (port->init_irqs) {
465		if (port->use_dma) {
466			if (port == &ports[0]) {
467#ifdef SYNC_SER_DMA
468				if (request_irq(24, tr_interrupt, 0,
469						"synchronous serial 1 dma tr",
470						&ports[0])) {
471					printk(KERN_CRIT "Can't alloc "
472						"sync serial port 1 IRQ");
473					goto out;
474				} else if (request_irq(25, rx_interrupt, 0,
475						"synchronous serial 1 dma rx",
476						&ports[0])) {
477					free_irq(24, &port[0]);
478					printk(KERN_CRIT "Can't alloc "
479						"sync serial port 1 IRQ");
480					goto out;
481				} else if (cris_request_dma(8,
482						"synchronous serial 1 dma tr",
483						DMA_VERBOSE_ON_ERROR,
484						dma_ser1)) {
485					free_irq(24, &port[0]);
486					free_irq(25, &port[0]);
487					printk(KERN_CRIT "Can't alloc "
488						"sync serial port 1 "
489						"TX DMA channel");
490					goto out;
491				} else if (cris_request_dma(9,
492						"synchronous serial 1 dma rec",
493						DMA_VERBOSE_ON_ERROR,
494						dma_ser1)) {
495					cris_free_dma(8, NULL);
496					free_irq(24, &port[0]);
497					free_irq(25, &port[0]);
498					printk(KERN_CRIT "Can't alloc "
499						"sync serial port 1 "
500						"RX DMA channel");
501					goto out;
502				}
503#endif
504				RESET_DMA(8); WAIT_DMA(8);
505				RESET_DMA(9); WAIT_DMA(9);
506				*R_DMA_CH8_CLR_INTR =
507					IO_STATE(R_DMA_CH8_CLR_INTR, clr_eop,
508						do) |
509					IO_STATE(R_DMA_CH8_CLR_INTR, clr_descr,
510						do);
511				*R_DMA_CH9_CLR_INTR =
512					IO_STATE(R_DMA_CH9_CLR_INTR, clr_eop,
513						do) |
514					IO_STATE(R_DMA_CH9_CLR_INTR, clr_descr,
515						do);
516				*R_IRQ_MASK2_SET =
517					IO_STATE(R_IRQ_MASK2_SET, dma8_eop,
518						set) |
519					IO_STATE(R_IRQ_MASK2_SET, dma9_descr,
520						set);
521			} else if (port == &ports[1]) {
522#ifdef SYNC_SER_DMA
523				if (request_irq(20, tr_interrupt, 0,
524						"synchronous serial 3 dma tr",
525						&ports[1])) {
526					printk(KERN_CRIT "Can't alloc "
527						"sync serial port 3 IRQ");
528					goto out;
529				} else if (request_irq(21, rx_interrupt, 0,
530						"synchronous serial 3 dma rx",
531						&ports[1])) {
532					free_irq(20, &ports[1]);
533					printk(KERN_CRIT "Can't alloc "
534						"sync serial port 3 IRQ");
535					goto out;
536				} else if (cris_request_dma(4,
537						"synchronous serial 3 dma tr",
538						DMA_VERBOSE_ON_ERROR,
539						dma_ser3)) {
540					free_irq(21, &ports[1]);
541					free_irq(20, &ports[1]);
542					printk(KERN_CRIT "Can't alloc "
543						"sync serial port 3 "
544						"TX DMA channel");
545					goto out;
546				} else if (cris_request_dma(5,
547						"synchronous serial 3 dma rec",
548						DMA_VERBOSE_ON_ERROR,
549						dma_ser3)) {
550					cris_free_dma(4, NULL);
551					free_irq(21, &ports[1]);
552					free_irq(20, &ports[1]);
553					printk(KERN_CRIT "Can't alloc "
554						"sync serial port 3 "
555						"RX DMA channel");
556					goto out;
557				}
558#endif
559				RESET_DMA(4); WAIT_DMA(4);
560				RESET_DMA(5); WAIT_DMA(5);
561				*R_DMA_CH4_CLR_INTR =
562					IO_STATE(R_DMA_CH4_CLR_INTR, clr_eop,
563						do) |
564					IO_STATE(R_DMA_CH4_CLR_INTR, clr_descr,
565						do);
566				*R_DMA_CH5_CLR_INTR =
567					IO_STATE(R_DMA_CH5_CLR_INTR, clr_eop,
568						do) |
569					IO_STATE(R_DMA_CH5_CLR_INTR, clr_descr,
570						do);
571				*R_IRQ_MASK2_SET =
572					IO_STATE(R_IRQ_MASK2_SET, dma4_eop,
573						set) |
574					IO_STATE(R_IRQ_MASK2_SET, dma5_descr,
575						set);
576			}
577			start_dma_in(port);
578			port->init_irqs = 0;
579		} else { /* !port->use_dma */
580#ifdef SYNC_SER_MANUAL
581			if (port == &ports[0]) {
582				if (request_irq(8,
583						manual_interrupt,
584						IRQF_SHARED,
585						"synchronous serial manual irq",
586						&ports[0])) {
587					printk(KERN_CRIT "Can't alloc "
588						"sync serial manual irq");
589					goto out;
590				}
591			} else if (port == &ports[1]) {
592				if (request_irq(8,
593						manual_interrupt,
594						IRQF_SHARED,
595						"synchronous serial manual irq",
596						&ports[1])) {
597					printk(KERN_CRIT "Can't alloc "
598						"sync serial manual irq");
599					goto out;
600				}
601			}
602			port->init_irqs = 0;
603#else
604			panic("sync_serial: Manual mode not supported.\n");
605#endif /* SYNC_SER_MANUAL */
606		}
607	} /* port->init_irqs */
608
609	port->busy++;
610	/* Start port if we use it as input */
611	mode = IO_EXTRACT(R_SYNC_SERIAL1_CTRL, mode, port->ctrl_data_shadow);
612	if (mode == IO_STATE_VALUE(R_SYNC_SERIAL1_CTRL, mode, master_input) ||
613	    mode == IO_STATE_VALUE(R_SYNC_SERIAL1_CTRL, mode, slave_input) ||
614	    mode == IO_STATE_VALUE(R_SYNC_SERIAL1_CTRL, mode, master_bidir) ||
615	    mode == IO_STATE_VALUE(R_SYNC_SERIAL1_CTRL, mode, slave_bidir)) {
616		SETS(port->ctrl_data_shadow, R_SYNC_SERIAL1_CTRL, clk_halt,
617			running);
618		SETS(port->ctrl_data_shadow, R_SYNC_SERIAL1_CTRL, tr_enable,
619			enable);
620		SETS(port->ctrl_data_shadow, R_SYNC_SERIAL1_CTRL, rec_enable,
621			enable);
622		port->started = 1;
623		*port->ctrl_data = port->ctrl_data_shadow;
624		if (!port->use_dma)
625			*R_IRQ_MASK1_SET = 1 << port->data_avail_bit;
626		DEBUG(printk(KERN_DEBUG "sser%d rec started\n", dev));
627	}
628	err = 0;
629
630out:
631	mutex_unlock(&sync_serial_mutex);
632	return err;
633}
634
635static int sync_serial_release(struct inode *inode, struct file *file)
636{
637	int dev = MINOR(inode->i_rdev);
638	struct sync_port *port;
639
640	if (dev < 0 || dev >= NUMBER_OF_PORTS || !ports[dev].enabled) {
641		DEBUG(printk(KERN_DEBUG "Invalid minor %d\n", dev));
642		return -ENODEV;
643	}
644	port = &ports[dev];
645	if (port->busy)
646		port->busy--;
647	if (!port->busy)
648		*R_IRQ_MASK1_CLR = ((1 << port->data_avail_bit) |
649				    (1 << port->transmitter_ready_bit));
650
651	return 0;
652}
653
654
655
656static unsigned int sync_serial_poll(struct file *file, poll_table *wait)
657{
658	int dev = MINOR(file_inode(file)->i_rdev);
659	unsigned int mask = 0;
660	struct sync_port *port;
661	DEBUGPOLL(static unsigned int prev_mask = 0);
662
663	port = &ports[dev];
664	poll_wait(file, &port->out_wait_q, wait);
665	poll_wait(file, &port->in_wait_q, wait);
666	/* Some room to write */
667	if (port->out_count < OUT_BUFFER_SIZE)
668		mask |=  POLLOUT | POLLWRNORM;
669	/* At least an inbufchunk of data */
670	if (sync_data_avail(port) >= port->inbufchunk)
671		mask |= POLLIN | POLLRDNORM;
672
673	DEBUGPOLL(if (mask != prev_mask)
674		printk(KERN_DEBUG "sync_serial_poll: mask 0x%08X %s %s\n",
675			mask,
676			mask & POLLOUT ? "POLLOUT" : "",
677			mask & POLLIN ? "POLLIN" : "");
678		prev_mask = mask;
679	);
680	return mask;
681}
682
683static int sync_serial_ioctl_unlocked(struct file *file,
684		  unsigned int cmd, unsigned long arg)
685{
686	int return_val = 0;
687	unsigned long flags;
688
689	int dev = MINOR(file_inode(file)->i_rdev);
690	struct sync_port *port;
691
692	if (dev < 0 || dev >= NUMBER_OF_PORTS || !ports[dev].enabled) {
693		DEBUG(printk(KERN_DEBUG "Invalid minor %d\n", dev));
694		return -1;
695	}
696	port = &ports[dev];
697
698	local_irq_save(flags);
699	/* Disable port while changing config */
700	if (dev) {
701		if (port->use_dma) {
702			RESET_DMA(4); WAIT_DMA(4);
703			port->tr_running = 0;
704			port->out_count = 0;
705			port->outp = port->out_buffer;
706			*R_DMA_CH4_CLR_INTR =
707				IO_STATE(R_DMA_CH4_CLR_INTR, clr_eop, do) |
708				IO_STATE(R_DMA_CH4_CLR_INTR, clr_descr, do);
709		}
710		SETS(gen_config_ii_shadow, R_GEN_CONFIG_II, sermode3, async);
711	} else {
712		if (port->use_dma) {
713			RESET_DMA(8); WAIT_DMA(8);
714			port->tr_running = 0;
715			port->out_count = 0;
716			port->outp = port->out_buffer;
717			*R_DMA_CH8_CLR_INTR =
718				IO_STATE(R_DMA_CH8_CLR_INTR, clr_eop, do) |
719				IO_STATE(R_DMA_CH8_CLR_INTR, clr_descr, do);
720		}
721		SETS(gen_config_ii_shadow, R_GEN_CONFIG_II, sermode1, async);
722	}
723	*R_GEN_CONFIG_II = gen_config_ii_shadow;
724	local_irq_restore(flags);
725
726	switch (cmd) {
727	case SSP_SPEED:
728		if (GET_SPEED(arg) == CODEC) {
729			if (dev)
730				SETS(sync_serial_prescale_shadow,
731					R_SYNC_SERIAL_PRESCALE, clk_sel_u3,
732					codec);
733			else
734				SETS(sync_serial_prescale_shadow,
735					R_SYNC_SERIAL_PRESCALE, clk_sel_u1,
736					codec);
737
738			SETF(sync_serial_prescale_shadow,
739				R_SYNC_SERIAL_PRESCALE, prescaler,
740				GET_FREQ(arg));
741			SETF(sync_serial_prescale_shadow,
742				R_SYNC_SERIAL_PRESCALE, frame_rate,
743				GET_FRAME_RATE(arg));
744			SETF(sync_serial_prescale_shadow,
745				R_SYNC_SERIAL_PRESCALE, word_rate,
746				GET_WORD_RATE(arg));
747		} else {
748			SETF(port->ctrl_data_shadow, R_SYNC_SERIAL1_CTRL,
749				tr_baud, GET_SPEED(arg));
750			if (dev)
751				SETS(sync_serial_prescale_shadow,
752					R_SYNC_SERIAL_PRESCALE, clk_sel_u3,
753					baudrate);
754			else
755				SETS(sync_serial_prescale_shadow,
756					R_SYNC_SERIAL_PRESCALE, clk_sel_u1,
757					baudrate);
758		}
759		break;
760	case SSP_MODE:
761		if (arg > 5)
762			return -EINVAL;
763		if (arg == MASTER_OUTPUT || arg == SLAVE_OUTPUT)
764			*R_IRQ_MASK1_CLR = 1 << port->data_avail_bit;
765		else if (!port->use_dma)
766			*R_IRQ_MASK1_SET = 1 << port->data_avail_bit;
767		SETF(port->ctrl_data_shadow, R_SYNC_SERIAL1_CTRL, mode, arg);
768		break;
769	case SSP_FRAME_SYNC:
770		if (arg & NORMAL_SYNC)
771			SETS(port->ctrl_data_shadow, R_SYNC_SERIAL1_CTRL,
772				f_synctype, normal);
773		else if (arg & EARLY_SYNC)
774			SETS(port->ctrl_data_shadow, R_SYNC_SERIAL1_CTRL,
775				f_synctype, early);
776
777		if (arg & BIT_SYNC)
778			SETS(port->ctrl_data_shadow, R_SYNC_SERIAL1_CTRL,
779				f_syncsize, bit);
780		else if (arg & WORD_SYNC)
781			SETS(port->ctrl_data_shadow, R_SYNC_SERIAL1_CTRL,
782				f_syncsize, word);
783		else if (arg & EXTENDED_SYNC)
784			SETS(port->ctrl_data_shadow, R_SYNC_SERIAL1_CTRL,
785				f_syncsize, extended);
786
787		if (arg & SYNC_ON)
788			SETS(port->ctrl_data_shadow, R_SYNC_SERIAL1_CTRL,
789				f_sync, on);
790		else if (arg & SYNC_OFF)
791			SETS(port->ctrl_data_shadow, R_SYNC_SERIAL1_CTRL,
792				f_sync, off);
793
794		if (arg & WORD_SIZE_8)
795			SETS(port->ctrl_data_shadow, R_SYNC_SERIAL1_CTRL,
796				wordsize, size8bit);
797		else if (arg & WORD_SIZE_12)
798			SETS(port->ctrl_data_shadow, R_SYNC_SERIAL1_CTRL,
799				wordsize, size12bit);
800		else if (arg & WORD_SIZE_16)
801			SETS(port->ctrl_data_shadow, R_SYNC_SERIAL1_CTRL,
802				wordsize, size16bit);
803		else if (arg & WORD_SIZE_24)
804			SETS(port->ctrl_data_shadow, R_SYNC_SERIAL1_CTRL,
805				wordsize, size24bit);
806		else if (arg & WORD_SIZE_32)
807			SETS(port->ctrl_data_shadow, R_SYNC_SERIAL1_CTRL,
808				wordsize, size32bit);
809
810		if (arg & BIT_ORDER_MSB)
811			SETS(port->ctrl_data_shadow, R_SYNC_SERIAL1_CTRL,
812				bitorder, msb);
813		else if (arg & BIT_ORDER_LSB)
814			SETS(port->ctrl_data_shadow, R_SYNC_SERIAL1_CTRL,
815				bitorder, lsb);
816
817		if (arg & FLOW_CONTROL_ENABLE)
818			SETS(port->ctrl_data_shadow, R_SYNC_SERIAL1_CTRL,
819				flow_ctrl, enabled);
820		else if (arg & FLOW_CONTROL_DISABLE)
821			SETS(port->ctrl_data_shadow, R_SYNC_SERIAL1_CTRL,
822				flow_ctrl, disabled);
823
824		if (arg & CLOCK_NOT_GATED)
825			SETS(port->ctrl_data_shadow, R_SYNC_SERIAL1_CTRL,
826				clk_mode, normal);
827		else if (arg & CLOCK_GATED)
828			SETS(port->ctrl_data_shadow, R_SYNC_SERIAL1_CTRL,
829				clk_mode, gated);
830
831		break;
832	case SSP_IPOLARITY:
833		/* NOTE!! negedge is considered NORMAL */
834		if (arg & CLOCK_NORMAL)
835			SETS(port->ctrl_data_shadow, R_SYNC_SERIAL1_CTRL,
836				clk_polarity, neg);
837		else if (arg & CLOCK_INVERT)
838			SETS(port->ctrl_data_shadow, R_SYNC_SERIAL1_CTRL,
839				clk_polarity, pos);
840
841		if (arg & FRAME_NORMAL)
842			SETS(port->ctrl_data_shadow, R_SYNC_SERIAL1_CTRL,
843				frame_polarity, normal);
844		else if (arg & FRAME_INVERT)
845			SETS(port->ctrl_data_shadow, R_SYNC_SERIAL1_CTRL,
846				frame_polarity, inverted);
847
848		if (arg & STATUS_NORMAL)
849			SETS(port->ctrl_data_shadow, R_SYNC_SERIAL1_CTRL,
850				status_polarity, normal);
851		else if (arg & STATUS_INVERT)
852			SETS(port->ctrl_data_shadow, R_SYNC_SERIAL1_CTRL,
853				status_polarity, inverted);
854		break;
855	case SSP_OPOLARITY:
856		if (arg & CLOCK_NORMAL)
857			SETS(port->ctrl_data_shadow, R_SYNC_SERIAL1_CTRL,
858				clk_driver, normal);
859		else if (arg & CLOCK_INVERT)
860			SETS(port->ctrl_data_shadow, R_SYNC_SERIAL1_CTRL,
861				clk_driver, inverted);
862
863		if (arg & FRAME_NORMAL)
864			SETS(port->ctrl_data_shadow, R_SYNC_SERIAL1_CTRL,
865				frame_driver, normal);
866		else if (arg & FRAME_INVERT)
867			SETS(port->ctrl_data_shadow, R_SYNC_SERIAL1_CTRL,
868				frame_driver, inverted);
869
870		if (arg & STATUS_NORMAL)
871			SETS(port->ctrl_data_shadow, R_SYNC_SERIAL1_CTRL,
872				status_driver, normal);
873		else if (arg & STATUS_INVERT)
874			SETS(port->ctrl_data_shadow, R_SYNC_SERIAL1_CTRL,
875				status_driver, inverted);
876		break;
877	case SSP_SPI:
878		SETS(port->ctrl_data_shadow, R_SYNC_SERIAL1_CTRL, flow_ctrl,
879			disabled);
880		SETS(port->ctrl_data_shadow, R_SYNC_SERIAL1_CTRL, bitorder,
881			msb);
882		SETS(port->ctrl_data_shadow, R_SYNC_SERIAL1_CTRL, wordsize,
883			size8bit);
884		SETS(port->ctrl_data_shadow, R_SYNC_SERIAL1_CTRL, f_sync, on);
885		SETS(port->ctrl_data_shadow, R_SYNC_SERIAL1_CTRL, f_syncsize,
886			word);
887		SETS(port->ctrl_data_shadow, R_SYNC_SERIAL1_CTRL, f_synctype,
888			normal);
889		if (arg & SPI_SLAVE) {
890			SETS(port->ctrl_data_shadow, R_SYNC_SERIAL1_CTRL,
891				frame_polarity, inverted);
892			SETS(port->ctrl_data_shadow, R_SYNC_SERIAL1_CTRL,
893				clk_polarity, neg);
894			SETF(port->ctrl_data_shadow, R_SYNC_SERIAL1_CTRL,
895				mode, SLAVE_INPUT);
896		} else {
897			SETS(port->ctrl_data_shadow, R_SYNC_SERIAL1_CTRL,
898				frame_driver, inverted);
899			SETS(port->ctrl_data_shadow, R_SYNC_SERIAL1_CTRL,
900				clk_driver, inverted);
901			SETF(port->ctrl_data_shadow, R_SYNC_SERIAL1_CTRL,
902				mode, MASTER_OUTPUT);
903		}
904		break;
905	case SSP_INBUFCHUNK:
906#if 0
907		if (arg > port->in_buffer_size/NUM_IN_DESCR)
908			return -EINVAL;
909		port->inbufchunk = arg;
910		/* Make sure in_buffer_size is a multiple of inbufchunk */
911		port->in_buffer_size =
912			(port->in_buffer_size/port->inbufchunk) *
913			port->inbufchunk;
914		DEBUG(printk(KERN_DEBUG "inbufchunk %i in_buffer_size: %i\n",
915			port->inbufchunk, port->in_buffer_size));
916		if (port->use_dma) {
917			if (port->port_nbr == 0) {
918				RESET_DMA(9);
919				WAIT_DMA(9);
920			} else {
921				RESET_DMA(5);
922				WAIT_DMA(5);
923			}
924			start_dma_in(port);
925		}
926#endif
927		break;
928	default:
929		return_val = -1;
930	}
931	/* Make sure we write the config without interruption */
932	local_irq_save(flags);
933	/* Set config and enable port */
934	*port->ctrl_data = port->ctrl_data_shadow;
935	nop(); nop(); nop(); nop();
936	*R_SYNC_SERIAL_PRESCALE = sync_serial_prescale_shadow;
937	nop(); nop(); nop(); nop();
938	if (dev)
939		SETS(gen_config_ii_shadow, R_GEN_CONFIG_II, sermode3, sync);
940	else
941		SETS(gen_config_ii_shadow, R_GEN_CONFIG_II, sermode1, sync);
942
943	*R_GEN_CONFIG_II = gen_config_ii_shadow;
944	/* Reset DMA. At readout from serial port the data could be shifted
945	 * one byte if not resetting DMA.
946	 */
947	if (port->use_dma) {
948		if (port->port_nbr == 0) {
949			RESET_DMA(9);
950			WAIT_DMA(9);
951		} else {
952			RESET_DMA(5);
953			WAIT_DMA(5);
954		}
955		start_dma_in(port);
956	}
957	local_irq_restore(flags);
958	return return_val;
959}
960
961static long sync_serial_ioctl(struct file *file,
962			      unsigned int cmd, unsigned long arg)
963{
964	long ret;
965
966	mutex_lock(&sync_serial_mutex);
967	ret = sync_serial_ioctl_unlocked(file, cmd, arg);
968	mutex_unlock(&sync_serial_mutex);
969
970	return ret;
971}
972
973
974static ssize_t sync_serial_write(struct file *file, const char *buf,
975	size_t count, loff_t *ppos)
976{
977	int dev = MINOR(file_inode(file)->i_rdev);
978	DECLARE_WAITQUEUE(wait, current);
979	struct sync_port *port;
980	unsigned long flags;
981	unsigned long c, c1;
982	unsigned long free_outp;
983	unsigned long outp;
984	unsigned long out_buffer;
985
986	if (dev < 0 || dev >= NUMBER_OF_PORTS || !ports[dev].enabled) {
987		DEBUG(printk(KERN_DEBUG "Invalid minor %d\n", dev));
988		return -ENODEV;
989	}
990	port = &ports[dev];
991
992	DEBUGWRITE(printk(KERN_DEBUG "W d%d c %lu (%d/%d)\n",
993		port->port_nbr, count, port->out_count, OUT_BUFFER_SIZE));
994	/* Space to end of buffer */
995	/*
996	 * out_buffer <c1>012345<-   c    ->OUT_BUFFER_SIZE
997	 *            outp^    +out_count
998	 *                      ^free_outp
999	 * out_buffer 45<-     c      ->0123OUT_BUFFER_SIZE
1000	 *             +out_count   outp^
1001	 *              free_outp
1002	 *
1003	 */
1004
1005	/* Read variables that may be updated by interrupts */
1006	local_irq_save(flags);
1007	if (count > OUT_BUFFER_SIZE - port->out_count)
1008		count = OUT_BUFFER_SIZE - port->out_count;
1009
1010	outp = (unsigned long)port->outp;
1011	free_outp = outp + port->out_count;
1012	local_irq_restore(flags);
1013	out_buffer = (unsigned long)port->out_buffer;
1014
1015	/* Find out where and how much to write */
1016	if (free_outp >= out_buffer + OUT_BUFFER_SIZE)
1017		free_outp -= OUT_BUFFER_SIZE;
1018	if (free_outp >= outp)
1019		c = out_buffer + OUT_BUFFER_SIZE - free_outp;
1020	else
1021		c = outp - free_outp;
1022	if (c > count)
1023		c = count;
1024
1025	DEBUGWRITE(printk(KERN_DEBUG "w op %08lX fop %08lX c %lu\n",
1026		outp, free_outp, c));
1027	if (copy_from_user((void *)free_outp, buf, c))
1028		return -EFAULT;
1029
1030	if (c != count) {
1031		buf += c;
1032		c1 = count - c;
1033		DEBUGWRITE(printk(KERN_DEBUG "w2 fi %lu c %lu c1 %lu\n",
1034			free_outp-out_buffer, c, c1));
1035		if (copy_from_user((void *)out_buffer, buf, c1))
1036			return -EFAULT;
1037	}
1038	local_irq_save(flags);
1039	port->out_count += count;
1040	local_irq_restore(flags);
1041
1042	/* Make sure transmitter/receiver is running */
1043	if (!port->started) {
1044		SETS(port->ctrl_data_shadow, R_SYNC_SERIAL1_CTRL, clk_halt,
1045			running);
1046		SETS(port->ctrl_data_shadow, R_SYNC_SERIAL1_CTRL, tr_enable,
1047			enable);
1048		SETS(port->ctrl_data_shadow, R_SYNC_SERIAL1_CTRL, rec_enable,
1049			enable);
1050		port->started = 1;
1051	}
1052
1053	*port->ctrl_data = port->ctrl_data_shadow;
1054
1055	if (file->f_flags & O_NONBLOCK)	{
1056		local_irq_save(flags);
1057		if (!port->tr_running) {
1058			if (!port->use_dma) {
1059				/* Start sender by writing data */
1060				send_word(port);
1061				/* and enable transmitter ready IRQ */
1062				*R_IRQ_MASK1_SET = 1 <<
1063					port->transmitter_ready_bit;
1064			} else
1065				start_dma(port,
1066					(unsigned char *volatile)port->outp, c);
1067		}
1068		local_irq_restore(flags);
1069		DEBUGWRITE(printk(KERN_DEBUG "w d%d c %lu NB\n",
1070			port->port_nbr, count));
1071		return count;
1072	}
1073
1074	/* Sleep until all sent */
1075	add_wait_queue(&port->out_wait_q, &wait);
1076	set_current_state(TASK_INTERRUPTIBLE);
1077	local_irq_save(flags);
1078	if (!port->tr_running) {
1079		if (!port->use_dma) {
1080			/* Start sender by writing data */
1081			send_word(port);
1082			/* and enable transmitter ready IRQ */
1083			*R_IRQ_MASK1_SET = 1 << port->transmitter_ready_bit;
1084		} else
1085			start_dma(port, port->outp, c);
1086	}
1087	local_irq_restore(flags);
1088	schedule();
1089	remove_wait_queue(&port->out_wait_q, &wait);
1090	if (signal_pending(current))
1091		return -EINTR;
1092
1093	DEBUGWRITE(printk(KERN_DEBUG "w d%d c %lu\n", port->port_nbr, count));
1094	return count;
1095}
1096
1097static ssize_t sync_serial_read(struct file *file, char *buf,
1098				size_t count, loff_t *ppos)
1099{
1100	int dev = MINOR(file_inode(file)->i_rdev);
1101	int avail;
1102	struct sync_port *port;
1103	unsigned char *start;
1104	unsigned char *end;
1105	unsigned long flags;
1106
1107	if (dev < 0 || dev >= NUMBER_OF_PORTS || !ports[dev].enabled) {
1108		DEBUG(printk(KERN_DEBUG "Invalid minor %d\n", dev));
1109		return -ENODEV;
1110	}
1111	port = &ports[dev];
1112
1113	DEBUGREAD(printk(KERN_DEBUG "R%d c %d ri %lu wi %lu /%lu\n",
1114		dev, count, port->readp - port->flip,
1115		port->writep - port->flip, port->in_buffer_size));
1116
1117	if (!port->started) {
1118		SETS(port->ctrl_data_shadow, R_SYNC_SERIAL1_CTRL, clk_halt,
1119			running);
1120		SETS(port->ctrl_data_shadow, R_SYNC_SERIAL1_CTRL, tr_enable,
1121			enable);
1122		SETS(port->ctrl_data_shadow, R_SYNC_SERIAL1_CTRL, rec_enable,
1123			enable);
1124		port->started = 1;
1125	}
1126	*port->ctrl_data = port->ctrl_data_shadow;
1127
1128	/* Calculate number of available bytes */
1129	/* Save pointers to avoid that they are modified by interrupt */
1130	local_irq_save(flags);
1131	start = (unsigned char *)port->readp; /* cast away volatile */
1132	end = (unsigned char *)port->writep;  /* cast away volatile */
1133	local_irq_restore(flags);
1134	while (start == end && !port->full) {
1135		/* No data */
1136		if (file->f_flags & O_NONBLOCK)
1137			return -EAGAIN;
1138
1139		wait_event_interruptible(port->in_wait_q,
1140					 !(start == end && !port->full));
1141		if (signal_pending(current))
1142			return -EINTR;
1143
1144		local_irq_save(flags);
1145		start = (unsigned char *)port->readp; /* cast away volatile */
1146		end = (unsigned char *)port->writep;  /* cast away volatile */
1147		local_irq_restore(flags);
1148	}
1149
1150	/* Lazy read, never return wrapped data. */
1151	if (port->full)
1152		avail = port->in_buffer_size;
1153	else if (end > start)
1154		avail = end - start;
1155	else
1156		avail = port->flip + port->in_buffer_size - start;
1157
1158	count = count > avail ? avail : count;
1159	if (copy_to_user(buf, start, count))
1160		return -EFAULT;
1161	/* Disable interrupts while updating readp */
1162	local_irq_save(flags);
1163	port->readp += count;
1164	if (port->readp >= port->flip + port->in_buffer_size) /* Wrap? */
1165		port->readp = port->flip;
1166	port->full = 0;
1167	local_irq_restore(flags);
1168	DEBUGREAD(printk(KERN_DEBUG "r %d\n", count));
1169	return count;
1170}
1171
1172static void send_word(struct sync_port *port)
1173{
1174	switch (IO_EXTRACT(R_SYNC_SERIAL1_CTRL, wordsize,
1175			port->ctrl_data_shadow)) {
1176	case IO_STATE_VALUE(R_SYNC_SERIAL1_CTRL, wordsize, size8bit):
1177		 port->out_count--;
1178		 *port->data_out = *port->outp++;
1179		 if (port->outp >= port->out_buffer + OUT_BUFFER_SIZE)
1180			 port->outp = port->out_buffer;
1181		 break;
1182	case IO_STATE_VALUE(R_SYNC_SERIAL1_CTRL, wordsize, size12bit):
1183	{
1184		int data = (*port->outp++) << 8;
1185		data |= *port->outp++;
1186		port->out_count -= 2;
1187		*port->data_out = data;
1188		if (port->outp >= port->out_buffer + OUT_BUFFER_SIZE)
1189			port->outp = port->out_buffer;
1190		break;
1191	}
1192	case IO_STATE_VALUE(R_SYNC_SERIAL1_CTRL, wordsize, size16bit):
1193		port->out_count -= 2;
1194		*port->data_out = *(unsigned short *)port->outp;
1195		port->outp += 2;
1196		if (port->outp >= port->out_buffer + OUT_BUFFER_SIZE)
1197			port->outp = port->out_buffer;
1198		break;
1199	case IO_STATE_VALUE(R_SYNC_SERIAL1_CTRL, wordsize, size24bit):
1200		port->out_count -= 3;
1201		*port->data_out = *(unsigned int *)port->outp;
1202		port->outp += 3;
1203		if (port->outp >= port->out_buffer + OUT_BUFFER_SIZE)
1204			port->outp = port->out_buffer;
1205		break;
1206	case IO_STATE_VALUE(R_SYNC_SERIAL1_CTRL, wordsize, size32bit):
1207		port->out_count -= 4;
1208		*port->data_out = *(unsigned int *)port->outp;
1209		port->outp += 4;
1210		if (port->outp >= port->out_buffer + OUT_BUFFER_SIZE)
1211			port->outp = port->out_buffer;
1212		break;
1213	}
1214}
1215
1216
1217static void start_dma(struct sync_port *port, const char *data, int count)
1218{
1219	port->tr_running = 1;
1220	port->out_descr.hw_len = 0;
1221	port->out_descr.next = 0;
1222	port->out_descr.ctrl = d_eol | d_eop; /* No d_wait to avoid glitches */
1223	port->out_descr.sw_len = count;
1224	port->out_descr.buf = virt_to_phys(data);
1225	port->out_descr.status = 0;
1226
1227	*port->output_dma_first = virt_to_phys(&port->out_descr);
1228	*port->output_dma_cmd = IO_STATE(R_DMA_CH0_CMD, cmd, start);
1229	DEBUGTXINT(printk(KERN_DEBUG "dma %08lX c %d\n",
1230		(unsigned long)data, count));
1231}
1232
1233static void start_dma_in(struct sync_port *port)
1234{
1235	int i;
1236	unsigned long buf;
1237	port->writep = port->flip;
1238
1239	if (port->writep > port->flip + port->in_buffer_size) {
1240		panic("Offset too large in sync serial driver\n");
1241		return;
1242	}
1243	buf = virt_to_phys(port->in_buffer);
1244	for (i = 0; i < NUM_IN_DESCR; i++) {
1245		port->in_descr[i].sw_len = port->inbufchunk;
1246		port->in_descr[i].ctrl = d_int;
1247		port->in_descr[i].next = virt_to_phys(&port->in_descr[i+1]);
1248		port->in_descr[i].buf = buf;
1249		port->in_descr[i].hw_len = 0;
1250		port->in_descr[i].status = 0;
1251		port->in_descr[i].fifo_len = 0;
1252		buf += port->inbufchunk;
1253		prepare_rx_descriptor(&port->in_descr[i]);
1254	}
1255	/* Link the last descriptor to the first */
1256	port->in_descr[i-1].next = virt_to_phys(&port->in_descr[0]);
1257	port->in_descr[i-1].ctrl |= d_eol;
1258	port->next_rx_desc = &port->in_descr[0];
1259	port->prev_rx_desc = &port->in_descr[NUM_IN_DESCR - 1];
1260	*port->input_dma_first = virt_to_phys(port->next_rx_desc);
1261	*port->input_dma_cmd = IO_STATE(R_DMA_CH0_CMD, cmd, start);
1262}
1263
1264#ifdef SYNC_SER_DMA
1265static irqreturn_t tr_interrupt(int irq, void *dev_id)
1266{
1267	unsigned long ireg = *R_IRQ_MASK2_RD;
1268	struct etrax_dma_descr *descr;
1269	unsigned int sentl;
1270	int handled = 0;
1271	int i;
1272
1273	for (i = 0; i < NUMBER_OF_PORTS; i++) {
1274		struct sync_port *port = &ports[i];
1275		if (!port->enabled  || !port->use_dma)
1276			continue;
1277
1278		/* IRQ active for the port? */
1279		if (!(ireg & (1 << port->output_dma_bit)))
1280			continue;
1281
1282		handled = 1;
1283
1284		/* Clear IRQ */
1285		*port->output_dma_clr_irq =
1286			IO_STATE(R_DMA_CH0_CLR_INTR, clr_eop, do) |
1287			IO_STATE(R_DMA_CH0_CLR_INTR, clr_descr, do);
1288
1289		descr = &port->out_descr;
1290		if (!(descr->status & d_stop))
1291			sentl = descr->sw_len;
1292		else
1293			/* Otherwise find amount of data sent here */
1294			sentl = descr->hw_len;
1295
1296		port->out_count -= sentl;
1297		port->outp += sentl;
1298		if (port->outp >= port->out_buffer + OUT_BUFFER_SIZE)
1299			port->outp = port->out_buffer;
1300		if (port->out_count) {
1301			int c = port->out_buffer + OUT_BUFFER_SIZE - port->outp;
1302			if (c > port->out_count)
1303				c = port->out_count;
1304			DEBUGTXINT(printk(KERN_DEBUG
1305				"tx_int DMAWRITE %i %i\n", sentl, c));
1306			start_dma(port, port->outp, c);
1307		} else  {
1308			DEBUGTXINT(printk(KERN_DEBUG
1309				"tx_int DMA stop %i\n", sentl));
1310			port->tr_running = 0;
1311		}
1312		/* wake up the waiting process */
1313		wake_up_interruptible(&port->out_wait_q);
1314	}
1315	return IRQ_RETVAL(handled);
1316} /* tr_interrupt */
1317
1318static irqreturn_t rx_interrupt(int irq, void *dev_id)
1319{
1320	unsigned long ireg = *R_IRQ_MASK2_RD;
1321	int i;
1322	int handled = 0;
1323
1324	for (i = 0; i < NUMBER_OF_PORTS; i++) {
1325		struct sync_port *port = &ports[i];
1326
1327		if (!port->enabled || !port->use_dma)
1328			continue;
1329
1330		if (!(ireg & (1 << port->input_dma_descr_bit)))
1331			continue;
1332
1333		/* Descriptor interrupt */
1334		handled = 1;
1335		while (*port->input_dma_descr !=
1336				virt_to_phys(port->next_rx_desc)) {
1337			if (port->writep + port->inbufchunk > port->flip +
1338					port->in_buffer_size) {
1339				int first_size = port->flip +
1340					port->in_buffer_size - port->writep;
1341				memcpy(port->writep,
1342					phys_to_virt(port->next_rx_desc->buf),
1343					first_size);
1344				memcpy(port->flip,
1345					phys_to_virt(port->next_rx_desc->buf +
1346					first_size),
1347					port->inbufchunk - first_size);
1348				port->writep = port->flip +
1349					port->inbufchunk - first_size;
1350			} else {
1351				memcpy(port->writep,
1352					phys_to_virt(port->next_rx_desc->buf),
1353					port->inbufchunk);
1354				port->writep += port->inbufchunk;
1355				if (port->writep >= port->flip
1356						+ port->in_buffer_size)
1357					port->writep = port->flip;
1358			}
1359			if (port->writep == port->readp)
1360				port->full = 1;
1361			prepare_rx_descriptor(port->next_rx_desc);
1362			port->next_rx_desc->ctrl |= d_eol;
1363			port->prev_rx_desc->ctrl &= ~d_eol;
1364			port->prev_rx_desc = phys_to_virt((unsigned)
1365				port->next_rx_desc);
1366			port->next_rx_desc = phys_to_virt((unsigned)
1367				port->next_rx_desc->next);
1368			/* Wake up the waiting process */
1369			wake_up_interruptible(&port->in_wait_q);
1370			*port->input_dma_cmd = IO_STATE(R_DMA_CH1_CMD,
1371				cmd, restart);
1372			/* DMA has reached end of descriptor */
1373			*port->input_dma_clr_irq = IO_STATE(R_DMA_CH0_CLR_INTR,
1374				clr_descr, do);
1375		}
1376	}
1377	return IRQ_RETVAL(handled);
1378} /* rx_interrupt */
1379#endif /* SYNC_SER_DMA */
1380
1381#ifdef SYNC_SER_MANUAL
1382static irqreturn_t manual_interrupt(int irq, void *dev_id)
1383{
1384	int i;
1385	int handled = 0;
1386
1387	for (i = 0; i < NUMBER_OF_PORTS; i++) {
1388		struct sync_port *port = &ports[i];
1389
1390		if (!port->enabled || port->use_dma)
1391			continue;
1392
1393		/* Data received? */
1394		if (*R_IRQ_MASK1_RD & (1 << port->data_avail_bit)) {
1395			handled = 1;
1396			/* Read data */
1397			switch (port->ctrl_data_shadow &
1398				IO_MASK(R_SYNC_SERIAL1_CTRL, wordsize)) {
1399			case IO_STATE(R_SYNC_SERIAL1_CTRL, wordsize, size8bit):
1400				*port->writep++ =
1401					*(volatile char *)port->data_in;
1402				break;
1403			case IO_STATE(R_SYNC_SERIAL1_CTRL, wordsize, size12bit):
1404			{
1405				int data = *(unsigned short *)port->data_in;
1406				*port->writep = (data & 0x0ff0) >> 4;
1407				*(port->writep + 1) = data & 0x0f;
1408				port->writep += 2;
1409				break;
1410			}
1411			case IO_STATE(R_SYNC_SERIAL1_CTRL, wordsize, size16bit):
1412				*(unsigned short *)port->writep =
1413					*(volatile unsigned short *)port->data_in;
1414				port->writep += 2;
1415				break;
1416			case IO_STATE(R_SYNC_SERIAL1_CTRL, wordsize, size24bit):
1417				*(unsigned int *)port->writep = *port->data_in;
1418				port->writep += 3;
1419				break;
1420			case IO_STATE(R_SYNC_SERIAL1_CTRL, wordsize, size32bit):
1421				*(unsigned int *)port->writep = *port->data_in;
1422				port->writep += 4;
1423				break;
1424			}
1425
1426			/* Wrap? */
1427			if (port->writep >= port->flip + port->in_buffer_size)
1428				port->writep = port->flip;
1429			if (port->writep == port->readp) {
1430				/* Receive buffer overrun, discard oldest */
1431				port->readp++;
1432				/* Wrap? */
1433				if (port->readp >= port->flip +
1434						port->in_buffer_size)
1435					port->readp = port->flip;
1436			}
1437			if (sync_data_avail(port) >= port->inbufchunk) {
1438				/* Wake up application */
1439				wake_up_interruptible(&port->in_wait_q);
1440			}
1441		}
1442
1443		/* Transmitter ready? */
1444		if (*R_IRQ_MASK1_RD & (1 << port->transmitter_ready_bit)) {
1445			if (port->out_count > 0) {
1446				/* More data to send */
1447				send_word(port);
1448			} else {
1449				/* Transmission finished */
1450				/* Turn off IRQ */
1451				*R_IRQ_MASK1_CLR = 1 <<
1452					port->transmitter_ready_bit;
1453				/* Wake up application */
1454				wake_up_interruptible(&port->out_wait_q);
1455			}
1456		}
1457	}
1458	return IRQ_RETVAL(handled);
1459}
1460#endif
1461
1462module_init(etrax_sync_serial_init);
1463