1/*
2 *  pti.c - PTI driver for cJTAG data extration
3 *
4 *  Copyright (C) Intel 2010
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 as
8 * published by the Free Software Foundation.
9 *
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13 * GNU General Public License for more details.
14 *
15 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
16 *
17 * The PTI (Parallel Trace Interface) driver directs trace data routed from
18 * various parts in the system out through the Intel Penwell PTI port and
19 * out of the mobile device for analysis with a debugging tool
20 * (Lauterbach, Fido). This is part of a solution for the MIPI P1149.7,
21 * compact JTAG, standard.
22 */
23
24#include <linux/init.h>
25#include <linux/sched.h>
26#include <linux/interrupt.h>
27#include <linux/console.h>
28#include <linux/kernel.h>
29#include <linux/module.h>
30#include <linux/tty.h>
31#include <linux/tty_driver.h>
32#include <linux/pci.h>
33#include <linux/mutex.h>
34#include <linux/miscdevice.h>
35#include <linux/pti.h>
36#include <linux/slab.h>
37#include <linux/uaccess.h>
38
39#define DRIVERNAME		"pti"
40#define PCINAME			"pciPTI"
41#define TTYNAME			"ttyPTI"
42#define CHARNAME		"pti"
43#define PTITTY_MINOR_START	0
44#define PTITTY_MINOR_NUM	2
45#define MAX_APP_IDS		16   /* 128 channel ids / u8 bit size */
46#define MAX_OS_IDS		16   /* 128 channel ids / u8 bit size */
47#define MAX_MODEM_IDS		16   /* 128 channel ids / u8 bit size */
48#define MODEM_BASE_ID		71   /* modem master ID address    */
49#define CONTROL_ID		72   /* control master ID address  */
50#define CONSOLE_ID		73   /* console master ID address  */
51#define OS_BASE_ID		74   /* base OS master ID address  */
52#define APP_BASE_ID		80   /* base App master ID address */
53#define CONTROL_FRAME_LEN	32   /* PTI control frame maximum size */
54#define USER_COPY_SIZE		8192 /* 8Kb buffer for user space copy */
55#define APERTURE_14		0x3800000 /* offset to first OS write addr */
56#define APERTURE_LEN		0x400000  /* address length */
57
58struct pti_tty {
59	struct pti_masterchannel *mc;
60};
61
62struct pti_dev {
63	struct tty_port port[PTITTY_MINOR_NUM];
64	unsigned long pti_addr;
65	unsigned long aperture_base;
66	void __iomem *pti_ioaddr;
67	u8 ia_app[MAX_APP_IDS];
68	u8 ia_os[MAX_OS_IDS];
69	u8 ia_modem[MAX_MODEM_IDS];
70};
71
72/*
73 * This protects access to ia_app, ia_os, and ia_modem,
74 * which keeps track of channels allocated in
75 * an aperture write id.
76 */
77static DEFINE_MUTEX(alloclock);
78
79static const struct pci_device_id pci_ids[] = {
80		{PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x82B)},
81		{0}
82};
83
84static struct tty_driver *pti_tty_driver;
85static struct pti_dev *drv_data;
86
87static unsigned int pti_console_channel;
88static unsigned int pti_control_channel;
89
90/**
91 *  pti_write_to_aperture()- The private write function to PTI HW.
92 *
93 *  @mc: The 'aperture'. It's part of a write address that holds
94 *       a master and channel ID.
95 *  @buf: Data being written to the HW that will ultimately be seen
96 *        in a debugging tool (Fido, Lauterbach).
97 *  @len: Size of buffer.
98 *
99 *  Since each aperture is specified by a unique
100 *  master/channel ID, no two processes will be writing
101 *  to the same aperture at the same time so no lock is required. The
102 *  PTI-Output agent will send these out in the order that they arrived, and
103 *  thus, it will intermix these messages. The debug tool can then later
104 *  regroup the appropriate message segments together reconstituting each
105 *  message.
106 */
107static void pti_write_to_aperture(struct pti_masterchannel *mc,
108				  u8 *buf,
109				  int len)
110{
111	int dwordcnt;
112	int final;
113	int i;
114	u32 ptiword;
115	u32 __iomem *aperture;
116	u8 *p = buf;
117
118	/*
119	 * calculate the aperture offset from the base using the master and
120	 * channel id's.
121	 */
122	aperture = drv_data->pti_ioaddr + (mc->master << 15)
123		+ (mc->channel << 8);
124
125	dwordcnt = len >> 2;
126	final = len - (dwordcnt << 2);	    /* final = trailing bytes    */
127	if (final == 0 && dwordcnt != 0) {  /* always need a final dword */
128		final += 4;
129		dwordcnt--;
130	}
131
132	for (i = 0; i < dwordcnt; i++) {
133		ptiword = be32_to_cpu(*(u32 *)p);
134		p += 4;
135		iowrite32(ptiword, aperture);
136	}
137
138	aperture += PTI_LASTDWORD_DTS;	/* adding DTS signals that is EOM */
139
140	ptiword = 0;
141	for (i = 0; i < final; i++)
142		ptiword |= *p++ << (24-(8*i));
143
144	iowrite32(ptiword, aperture);
145	return;
146}
147
148/**
149 *  pti_control_frame_built_and_sent()- control frame build and send function.
150 *
151 *  @mc:          The master / channel structure on which the function
152 *                built a control frame.
153 *  @thread_name: The thread name associated with the master / channel or
154 *                'NULL' if using the 'current' global variable.
155 *
156 *  To be able to post process the PTI contents on host side, a control frame
157 *  is added before sending any PTI content. So the host side knows on
158 *  each PTI frame the name of the thread using a dedicated master / channel.
159 *  The thread name is retrieved from 'current' global variable if 'thread_name'
160 *  is 'NULL', else it is retrieved from 'thread_name' parameter.
161 *  This function builds this frame and sends it to a master ID CONTROL_ID.
162 *  The overhead is only 32 bytes since the driver only writes to HW
163 *  in 32 byte chunks.
164 */
165static void pti_control_frame_built_and_sent(struct pti_masterchannel *mc,
166					     const char *thread_name)
167{
168	/*
169	 * Since we access the comm member in current's task_struct, we only
170	 * need to be as large as what 'comm' in that structure is.
171	 */
172	char comm[TASK_COMM_LEN];
173	struct pti_masterchannel mccontrol = {.master = CONTROL_ID,
174					      .channel = 0};
175	const char *thread_name_p;
176	const char *control_format = "%3d %3d %s";
177	u8 control_frame[CONTROL_FRAME_LEN];
178
179	if (!thread_name) {
180		if (!in_interrupt())
181			get_task_comm(comm, current);
182		else
183			strncpy(comm, "Interrupt", TASK_COMM_LEN);
184
185		/* Absolutely ensure our buffer is zero terminated. */
186		comm[TASK_COMM_LEN-1] = 0;
187		thread_name_p = comm;
188	} else {
189		thread_name_p = thread_name;
190	}
191
192	mccontrol.channel = pti_control_channel;
193	pti_control_channel = (pti_control_channel + 1) & 0x7f;
194
195	snprintf(control_frame, CONTROL_FRAME_LEN, control_format, mc->master,
196		mc->channel, thread_name_p);
197	pti_write_to_aperture(&mccontrol, control_frame, strlen(control_frame));
198}
199
200/**
201 *  pti_write_full_frame_to_aperture()- high level function to
202 *					write to PTI.
203 *
204 *  @mc:  The 'aperture'. It's part of a write address that holds
205 *        a master and channel ID.
206 *  @buf: Data being written to the HW that will ultimately be seen
207 *        in a debugging tool (Fido, Lauterbach).
208 *  @len: Size of buffer.
209 *
210 *  All threads sending data (either console, user space application, ...)
211 *  are calling the high level function to write to PTI meaning that it is
212 *  possible to add a control frame before sending the content.
213 */
214static void pti_write_full_frame_to_aperture(struct pti_masterchannel *mc,
215						const unsigned char *buf,
216						int len)
217{
218	pti_control_frame_built_and_sent(mc, NULL);
219	pti_write_to_aperture(mc, (u8 *)buf, len);
220}
221
222/**
223 * get_id()- Allocate a master and channel ID.
224 *
225 * @id_array:    an array of bits representing what channel
226 *               id's are allocated for writing.
227 * @max_ids:     The max amount of available write IDs to use.
228 * @base_id:     The starting SW channel ID, based on the Intel
229 *               PTI arch.
230 * @thread_name: The thread name associated with the master / channel or
231 *               'NULL' if using the 'current' global variable.
232 *
233 * Returns:
234 *	pti_masterchannel struct with master, channel ID address
235 *	0 for error
236 *
237 * Each bit in the arrays ia_app and ia_os correspond to a master and
238 * channel id. The bit is one if the id is taken and 0 if free. For
239 * every master there are 128 channel id's.
240 */
241static struct pti_masterchannel *get_id(u8 *id_array,
242					int max_ids,
243					int base_id,
244					const char *thread_name)
245{
246	struct pti_masterchannel *mc;
247	int i, j, mask;
248
249	mc = kmalloc(sizeof(struct pti_masterchannel), GFP_KERNEL);
250	if (mc == NULL)
251		return NULL;
252
253	/* look for a byte with a free bit */
254	for (i = 0; i < max_ids; i++)
255		if (id_array[i] != 0xff)
256			break;
257	if (i == max_ids) {
258		kfree(mc);
259		return NULL;
260	}
261	/* find the bit in the 128 possible channel opportunities */
262	mask = 0x80;
263	for (j = 0; j < 8; j++) {
264		if ((id_array[i] & mask) == 0)
265			break;
266		mask >>= 1;
267	}
268
269	/* grab it */
270	id_array[i] |= mask;
271	mc->master  = base_id;
272	mc->channel = ((i & 0xf)<<3) + j;
273	/* write new master Id / channel Id allocation to channel control */
274	pti_control_frame_built_and_sent(mc, thread_name);
275	return mc;
276}
277
278/*
279 * The following three functions:
280 * pti_request_mastercahannel(), mipi_release_masterchannel()
281 * and pti_writedata() are an API for other kernel drivers to
282 * access PTI.
283 */
284
285/**
286 * pti_request_masterchannel()- Kernel API function used to allocate
287 *				a master, channel ID address
288 *				to write to PTI HW.
289 *
290 * @type:        0- request Application  master, channel aperture ID
291 *                  write address.
292 *               1- request OS master, channel aperture ID write
293 *                  address.
294 *               2- request Modem master, channel aperture ID
295 *                  write address.
296 *               Other values, error.
297 * @thread_name: The thread name associated with the master / channel or
298 *               'NULL' if using the 'current' global variable.
299 *
300 * Returns:
301 *	pti_masterchannel struct
302 *	0 for error
303 */
304struct pti_masterchannel *pti_request_masterchannel(u8 type,
305						    const char *thread_name)
306{
307	struct pti_masterchannel *mc;
308
309	mutex_lock(&alloclock);
310
311	switch (type) {
312
313	case 0:
314		mc = get_id(drv_data->ia_app, MAX_APP_IDS,
315			    APP_BASE_ID, thread_name);
316		break;
317
318	case 1:
319		mc = get_id(drv_data->ia_os, MAX_OS_IDS,
320			    OS_BASE_ID, thread_name);
321		break;
322
323	case 2:
324		mc = get_id(drv_data->ia_modem, MAX_MODEM_IDS,
325			    MODEM_BASE_ID, thread_name);
326		break;
327	default:
328		mc = NULL;
329	}
330
331	mutex_unlock(&alloclock);
332	return mc;
333}
334EXPORT_SYMBOL_GPL(pti_request_masterchannel);
335
336/**
337 * pti_release_masterchannel()- Kernel API function used to release
338 *				a master, channel ID address
339 *				used to write to PTI HW.
340 *
341 * @mc: master, channel apeture ID address to be released.  This
342 *      will de-allocate the structure via kfree().
343 */
344void pti_release_masterchannel(struct pti_masterchannel *mc)
345{
346	u8 master, channel, i;
347
348	mutex_lock(&alloclock);
349
350	if (mc) {
351		master = mc->master;
352		channel = mc->channel;
353
354		if (master == APP_BASE_ID) {
355			i = channel >> 3;
356			drv_data->ia_app[i] &=  ~(0x80>>(channel & 0x7));
357		} else if (master == OS_BASE_ID) {
358			i = channel >> 3;
359			drv_data->ia_os[i] &= ~(0x80>>(channel & 0x7));
360		} else {
361			i = channel >> 3;
362			drv_data->ia_modem[i] &= ~(0x80>>(channel & 0x7));
363		}
364
365		kfree(mc);
366	}
367
368	mutex_unlock(&alloclock);
369}
370EXPORT_SYMBOL_GPL(pti_release_masterchannel);
371
372/**
373 * pti_writedata()- Kernel API function used to write trace
374 *                  debugging data to PTI HW.
375 *
376 * @mc:    Master, channel aperture ID address to write to.
377 *         Null value will return with no write occurring.
378 * @buf:   Trace debuging data to write to the PTI HW.
379 *         Null value will return with no write occurring.
380 * @count: Size of buf. Value of 0 or a negative number will
381 *         return with no write occuring.
382 */
383void pti_writedata(struct pti_masterchannel *mc, u8 *buf, int count)
384{
385	/*
386	 * since this function is exported, this is treated like an
387	 * API function, thus, all parameters should
388	 * be checked for validity.
389	 */
390	if ((mc != NULL) && (buf != NULL) && (count > 0))
391		pti_write_to_aperture(mc, buf, count);
392	return;
393}
394EXPORT_SYMBOL_GPL(pti_writedata);
395
396/*
397 * for the tty_driver_*() basic function descriptions, see tty_driver.h.
398 * Specific header comments made for PTI-related specifics.
399 */
400
401/**
402 * pti_tty_driver_open()- Open an Application master, channel aperture
403 * ID to the PTI device via tty device.
404 *
405 * @tty: tty interface.
406 * @filp: filp interface pased to tty_port_open() call.
407 *
408 * Returns:
409 *	int, 0 for success
410 *	otherwise, fail value
411 *
412 * The main purpose of using the tty device interface is for
413 * each tty port to have a unique PTI write aperture.  In an
414 * example use case, ttyPTI0 gets syslogd and an APP aperture
415 * ID and ttyPTI1 is where the n_tracesink ldisc hooks to route
416 * modem messages into PTI.  Modem trace data does not have to
417 * go to ttyPTI1, but ttyPTI0 and ttyPTI1 do need to be distinct
418 * master IDs.  These messages go through the PTI HW and out of
419 * the handheld platform and to the Fido/Lauterbach device.
420 */
421static int pti_tty_driver_open(struct tty_struct *tty, struct file *filp)
422{
423	/*
424	 * we actually want to allocate a new channel per open, per
425	 * system arch.  HW gives more than plenty channels for a single
426	 * system task to have its own channel to write trace data. This
427	 * also removes a locking requirement for the actual write
428	 * procedure.
429	 */
430	return tty_port_open(tty->port, tty, filp);
431}
432
433/**
434 * pti_tty_driver_close()- close tty device and release Application
435 * master, channel aperture ID to the PTI device via tty device.
436 *
437 * @tty: tty interface.
438 * @filp: filp interface pased to tty_port_close() call.
439 *
440 * The main purpose of using the tty device interface is to route
441 * syslog daemon messages to the PTI HW and out of the handheld platform
442 * and to the Fido/Lauterbach device.
443 */
444static void pti_tty_driver_close(struct tty_struct *tty, struct file *filp)
445{
446	tty_port_close(tty->port, tty, filp);
447}
448
449/**
450 * pti_tty_install()- Used to set up specific master-channels
451 *		      to tty ports for organizational purposes when
452 *		      tracing viewed from debuging tools.
453 *
454 * @driver: tty driver information.
455 * @tty: tty struct containing pti information.
456 *
457 * Returns:
458 *	0 for success
459 *	otherwise, error
460 */
461static int pti_tty_install(struct tty_driver *driver, struct tty_struct *tty)
462{
463	int idx = tty->index;
464	struct pti_tty *pti_tty_data;
465	int ret = tty_standard_install(driver, tty);
466
467	if (ret == 0) {
468		pti_tty_data = kmalloc(sizeof(struct pti_tty), GFP_KERNEL);
469		if (pti_tty_data == NULL)
470			return -ENOMEM;
471
472		if (idx == PTITTY_MINOR_START)
473			pti_tty_data->mc = pti_request_masterchannel(0, NULL);
474		else
475			pti_tty_data->mc = pti_request_masterchannel(2, NULL);
476
477		if (pti_tty_data->mc == NULL) {
478			kfree(pti_tty_data);
479			return -ENXIO;
480		}
481		tty->driver_data = pti_tty_data;
482	}
483
484	return ret;
485}
486
487/**
488 * pti_tty_cleanup()- Used to de-allocate master-channel resources
489 *		      tied to tty's of this driver.
490 *
491 * @tty: tty struct containing pti information.
492 */
493static void pti_tty_cleanup(struct tty_struct *tty)
494{
495	struct pti_tty *pti_tty_data = tty->driver_data;
496	if (pti_tty_data == NULL)
497		return;
498	pti_release_masterchannel(pti_tty_data->mc);
499	kfree(pti_tty_data);
500	tty->driver_data = NULL;
501}
502
503/**
504 * pti_tty_driver_write()-  Write trace debugging data through the char
505 * interface to the PTI HW.  Part of the misc device implementation.
506 *
507 * @filp: Contains private data which is used to obtain
508 *        master, channel write ID.
509 * @data: trace data to be written.
510 * @len:  # of byte to write.
511 *
512 * Returns:
513 *	int, # of bytes written
514 *	otherwise, error
515 */
516static int pti_tty_driver_write(struct tty_struct *tty,
517	const unsigned char *buf, int len)
518{
519	struct pti_tty *pti_tty_data = tty->driver_data;
520	if ((pti_tty_data != NULL) && (pti_tty_data->mc != NULL)) {
521		pti_write_to_aperture(pti_tty_data->mc, (u8 *)buf, len);
522		return len;
523	}
524	/*
525	 * we can't write to the pti hardware if the private driver_data
526	 * and the mc address is not there.
527	 */
528	else
529		return -EFAULT;
530}
531
532/**
533 * pti_tty_write_room()- Always returns 2048.
534 *
535 * @tty: contains tty info of the pti driver.
536 */
537static int pti_tty_write_room(struct tty_struct *tty)
538{
539	return 2048;
540}
541
542/**
543 * pti_char_open()- Open an Application master, channel aperture
544 * ID to the PTI device. Part of the misc device implementation.
545 *
546 * @inode: not used.
547 * @filp:  Output- will have a masterchannel struct set containing
548 *                 the allocated application PTI aperture write address.
549 *
550 * Returns:
551 *	int, 0 for success
552 *	otherwise, a fail value
553 */
554static int pti_char_open(struct inode *inode, struct file *filp)
555{
556	struct pti_masterchannel *mc;
557
558	/*
559	 * We really do want to fail immediately if
560	 * pti_request_masterchannel() fails,
561	 * before assigning the value to filp->private_data.
562	 * Slightly easier to debug if this driver needs debugging.
563	 */
564	mc = pti_request_masterchannel(0, NULL);
565	if (mc == NULL)
566		return -ENOMEM;
567	filp->private_data = mc;
568	return 0;
569}
570
571/**
572 * pti_char_release()-  Close a char channel to the PTI device. Part
573 * of the misc device implementation.
574 *
575 * @inode: Not used in this implementaiton.
576 * @filp:  Contains private_data that contains the master, channel
577 *         ID to be released by the PTI device.
578 *
579 * Returns:
580 *	always 0
581 */
582static int pti_char_release(struct inode *inode, struct file *filp)
583{
584	pti_release_masterchannel(filp->private_data);
585	filp->private_data = NULL;
586	return 0;
587}
588
589/**
590 * pti_char_write()-  Write trace debugging data through the char
591 * interface to the PTI HW.  Part of the misc device implementation.
592 *
593 * @filp:  Contains private data which is used to obtain
594 *         master, channel write ID.
595 * @data:  trace data to be written.
596 * @len:   # of byte to write.
597 * @ppose: Not used in this function implementation.
598 *
599 * Returns:
600 *	int, # of bytes written
601 *	otherwise, error value
602 *
603 * Notes: From side discussions with Alan Cox and experimenting
604 * with PTI debug HW like Nokia's Fido box and Lauterbach
605 * devices, 8192 byte write buffer used by USER_COPY_SIZE was
606 * deemed an appropriate size for this type of usage with
607 * debugging HW.
608 */
609static ssize_t pti_char_write(struct file *filp, const char __user *data,
610			      size_t len, loff_t *ppose)
611{
612	struct pti_masterchannel *mc;
613	void *kbuf;
614	const char __user *tmp;
615	size_t size = USER_COPY_SIZE;
616	size_t n = 0;
617
618	tmp = data;
619	mc = filp->private_data;
620
621	kbuf = kmalloc(size, GFP_KERNEL);
622	if (kbuf == NULL)  {
623		pr_err("%s(%d): buf allocation failed\n",
624			__func__, __LINE__);
625		return -ENOMEM;
626	}
627
628	do {
629		if (len - n > USER_COPY_SIZE)
630			size = USER_COPY_SIZE;
631		else
632			size = len - n;
633
634		if (copy_from_user(kbuf, tmp, size)) {
635			kfree(kbuf);
636			return n ? n : -EFAULT;
637		}
638
639		pti_write_to_aperture(mc, kbuf, size);
640		n  += size;
641		tmp += size;
642
643	} while (len > n);
644
645	kfree(kbuf);
646	return len;
647}
648
649static const struct tty_operations pti_tty_driver_ops = {
650	.open		= pti_tty_driver_open,
651	.close		= pti_tty_driver_close,
652	.write		= pti_tty_driver_write,
653	.write_room	= pti_tty_write_room,
654	.install	= pti_tty_install,
655	.cleanup	= pti_tty_cleanup
656};
657
658static const struct file_operations pti_char_driver_ops = {
659	.owner		= THIS_MODULE,
660	.write		= pti_char_write,
661	.open		= pti_char_open,
662	.release	= pti_char_release,
663};
664
665static struct miscdevice pti_char_driver = {
666	.minor		= MISC_DYNAMIC_MINOR,
667	.name		= CHARNAME,
668	.fops		= &pti_char_driver_ops
669};
670
671/**
672 * pti_console_write()-  Write to the console that has been acquired.
673 *
674 * @c:   Not used in this implementaiton.
675 * @buf: Data to be written.
676 * @len: Length of buf.
677 */
678static void pti_console_write(struct console *c, const char *buf, unsigned len)
679{
680	static struct pti_masterchannel mc = {.master  = CONSOLE_ID,
681					      .channel = 0};
682
683	mc.channel = pti_console_channel;
684	pti_console_channel = (pti_console_channel + 1) & 0x7f;
685
686	pti_write_full_frame_to_aperture(&mc, buf, len);
687}
688
689/**
690 * pti_console_device()-  Return the driver tty structure and set the
691 *			  associated index implementation.
692 *
693 * @c:     Console device of the driver.
694 * @index: index associated with c.
695 *
696 * Returns:
697 *	always value of pti_tty_driver structure when this function
698 *	is called.
699 */
700static struct tty_driver *pti_console_device(struct console *c, int *index)
701{
702	*index = c->index;
703	return pti_tty_driver;
704}
705
706/**
707 * pti_console_setup()-  Initialize console variables used by the driver.
708 *
709 * @c:     Not used.
710 * @opts:  Not used.
711 *
712 * Returns:
713 *	always 0.
714 */
715static int pti_console_setup(struct console *c, char *opts)
716{
717	pti_console_channel = 0;
718	pti_control_channel = 0;
719	return 0;
720}
721
722/*
723 * pti_console struct, used to capture OS printk()'s and shift
724 * out to the PTI device for debugging.  This cannot be
725 * enabled upon boot because of the possibility of eating
726 * any serial console printk's (race condition discovered).
727 * The console should be enabled upon when the tty port is
728 * used for the first time.  Since the primary purpose for
729 * the tty port is to hook up syslog to it, the tty port
730 * will be open for a really long time.
731 */
732static struct console pti_console = {
733	.name		= TTYNAME,
734	.write		= pti_console_write,
735	.device		= pti_console_device,
736	.setup		= pti_console_setup,
737	.flags		= CON_PRINTBUFFER,
738	.index		= 0,
739};
740
741/**
742 * pti_port_activate()- Used to start/initialize any items upon
743 * first opening of tty_port().
744 *
745 * @port- The tty port number of the PTI device.
746 * @tty-  The tty struct associated with this device.
747 *
748 * Returns:
749 *	always returns 0
750 *
751 * Notes: The primary purpose of the PTI tty port 0 is to hook
752 * the syslog daemon to it; thus this port will be open for a
753 * very long time.
754 */
755static int pti_port_activate(struct tty_port *port, struct tty_struct *tty)
756{
757	if (port->tty->index == PTITTY_MINOR_START)
758		console_start(&pti_console);
759	return 0;
760}
761
762/**
763 * pti_port_shutdown()- Used to stop/shutdown any items upon the
764 * last tty port close.
765 *
766 * @port- The tty port number of the PTI device.
767 *
768 * Notes: The primary purpose of the PTI tty port 0 is to hook
769 * the syslog daemon to it; thus this port will be open for a
770 * very long time.
771 */
772static void pti_port_shutdown(struct tty_port *port)
773{
774	if (port->tty->index == PTITTY_MINOR_START)
775		console_stop(&pti_console);
776}
777
778static const struct tty_port_operations tty_port_ops = {
779	.activate = pti_port_activate,
780	.shutdown = pti_port_shutdown,
781};
782
783/*
784 * Note the _probe() call sets everything up and ties the char and tty
785 * to successfully detecting the PTI device on the pci bus.
786 */
787
788/**
789 * pti_pci_probe()- Used to detect pti on the pci bus and set
790 *		    things up in the driver.
791 *
792 * @pdev- pci_dev struct values for pti.
793 * @ent-  pci_device_id struct for pti driver.
794 *
795 * Returns:
796 *	0 for success
797 *	otherwise, error
798 */
799static int pti_pci_probe(struct pci_dev *pdev,
800		const struct pci_device_id *ent)
801{
802	unsigned int a;
803	int retval = -EINVAL;
804	int pci_bar = 1;
805
806	dev_dbg(&pdev->dev, "%s %s(%d): PTI PCI ID %04x:%04x\n", __FILE__,
807			__func__, __LINE__, pdev->vendor, pdev->device);
808
809	retval = misc_register(&pti_char_driver);
810	if (retval) {
811		pr_err("%s(%d): CHAR registration failed of pti driver\n",
812			__func__, __LINE__);
813		pr_err("%s(%d): Error value returned: %d\n",
814			__func__, __LINE__, retval);
815		goto err;
816	}
817
818	retval = pci_enable_device(pdev);
819	if (retval != 0) {
820		dev_err(&pdev->dev,
821			"%s: pci_enable_device() returned error %d\n",
822			__func__, retval);
823		goto err_unreg_misc;
824	}
825
826	drv_data = kzalloc(sizeof(*drv_data), GFP_KERNEL);
827	if (drv_data == NULL) {
828		retval = -ENOMEM;
829		dev_err(&pdev->dev,
830			"%s(%d): kmalloc() returned NULL memory.\n",
831			__func__, __LINE__);
832		goto err_disable_pci;
833	}
834	drv_data->pti_addr = pci_resource_start(pdev, pci_bar);
835
836	retval = pci_request_region(pdev, pci_bar, dev_name(&pdev->dev));
837	if (retval != 0) {
838		dev_err(&pdev->dev,
839			"%s(%d): pci_request_region() returned error %d\n",
840			__func__, __LINE__, retval);
841		goto err_free_dd;
842	}
843	drv_data->aperture_base = drv_data->pti_addr+APERTURE_14;
844	drv_data->pti_ioaddr =
845		ioremap_nocache((u32)drv_data->aperture_base,
846		APERTURE_LEN);
847	if (!drv_data->pti_ioaddr) {
848		retval = -ENOMEM;
849		goto err_rel_reg;
850	}
851
852	pci_set_drvdata(pdev, drv_data);
853
854	for (a = 0; a < PTITTY_MINOR_NUM; a++) {
855		struct tty_port *port = &drv_data->port[a];
856		tty_port_init(port);
857		port->ops = &tty_port_ops;
858
859		tty_port_register_device(port, pti_tty_driver, a, &pdev->dev);
860	}
861
862	register_console(&pti_console);
863
864	return 0;
865err_rel_reg:
866	pci_release_region(pdev, pci_bar);
867err_free_dd:
868	kfree(drv_data);
869err_disable_pci:
870	pci_disable_device(pdev);
871err_unreg_misc:
872	misc_deregister(&pti_char_driver);
873err:
874	return retval;
875}
876
877/**
878 * pti_pci_remove()- Driver exit method to remove PTI from
879 *		   PCI bus.
880 * @pdev: variable containing pci info of PTI.
881 */
882static void pti_pci_remove(struct pci_dev *pdev)
883{
884	struct pti_dev *drv_data = pci_get_drvdata(pdev);
885	unsigned int a;
886
887	unregister_console(&pti_console);
888
889	for (a = 0; a < PTITTY_MINOR_NUM; a++) {
890		tty_unregister_device(pti_tty_driver, a);
891		tty_port_destroy(&drv_data->port[a]);
892	}
893
894	iounmap(drv_data->pti_ioaddr);
895	kfree(drv_data);
896	pci_release_region(pdev, 1);
897	pci_disable_device(pdev);
898
899	misc_deregister(&pti_char_driver);
900}
901
902static struct pci_driver pti_pci_driver = {
903	.name		= PCINAME,
904	.id_table	= pci_ids,
905	.probe		= pti_pci_probe,
906	.remove		= pti_pci_remove,
907};
908
909/**
910 *
911 * pti_init()- Overall entry/init call to the pti driver.
912 *             It starts the registration process with the kernel.
913 *
914 * Returns:
915 *	int __init, 0 for success
916 *	otherwise value is an error
917 *
918 */
919static int __init pti_init(void)
920{
921	int retval = -EINVAL;
922
923	/* First register module as tty device */
924
925	pti_tty_driver = alloc_tty_driver(PTITTY_MINOR_NUM);
926	if (pti_tty_driver == NULL) {
927		pr_err("%s(%d): Memory allocation failed for ptiTTY driver\n",
928			__func__, __LINE__);
929		return -ENOMEM;
930	}
931
932	pti_tty_driver->driver_name		= DRIVERNAME;
933	pti_tty_driver->name			= TTYNAME;
934	pti_tty_driver->major			= 0;
935	pti_tty_driver->minor_start		= PTITTY_MINOR_START;
936	pti_tty_driver->type			= TTY_DRIVER_TYPE_SYSTEM;
937	pti_tty_driver->subtype			= SYSTEM_TYPE_SYSCONS;
938	pti_tty_driver->flags			= TTY_DRIVER_REAL_RAW |
939						  TTY_DRIVER_DYNAMIC_DEV;
940	pti_tty_driver->init_termios		= tty_std_termios;
941
942	tty_set_operations(pti_tty_driver, &pti_tty_driver_ops);
943
944	retval = tty_register_driver(pti_tty_driver);
945	if (retval) {
946		pr_err("%s(%d): TTY registration failed of pti driver\n",
947			__func__, __LINE__);
948		pr_err("%s(%d): Error value returned: %d\n",
949			__func__, __LINE__, retval);
950
951		goto put_tty;
952	}
953
954	retval = pci_register_driver(&pti_pci_driver);
955	if (retval) {
956		pr_err("%s(%d): PCI registration failed of pti driver\n",
957			__func__, __LINE__);
958		pr_err("%s(%d): Error value returned: %d\n",
959			__func__, __LINE__, retval);
960		goto unreg_tty;
961	}
962
963	return 0;
964unreg_tty:
965	tty_unregister_driver(pti_tty_driver);
966put_tty:
967	put_tty_driver(pti_tty_driver);
968	pti_tty_driver = NULL;
969	return retval;
970}
971
972/**
973 * pti_exit()- Unregisters this module as a tty and pci driver.
974 */
975static void __exit pti_exit(void)
976{
977	tty_unregister_driver(pti_tty_driver);
978	pci_unregister_driver(&pti_pci_driver);
979	put_tty_driver(pti_tty_driver);
980}
981
982module_init(pti_init);
983module_exit(pti_exit);
984
985MODULE_LICENSE("GPL");
986MODULE_AUTHOR("Ken Mills, Jay Freyensee");
987MODULE_DESCRIPTION("PTI Driver");
988
989