[linux.git] / drivers / char / snsc.c

/*
 * SN Platform system controller communication support
 *
 * This file is subject to the terms and conditions of the GNU General Public
 * License.  See the file "COPYING" in the main directory of this archive
 * for more details.
 *
 * Copyright (C) 2004, 2006 Silicon Graphics, Inc. All rights reserved.
 */

/*
 * System controller communication driver
 *
 * This driver allows a user process to communicate with the system
 * controller (a.k.a. "IRouter") network in an SGI SN system.
 */

#include <linux/interrupt.h>
#include <linux/sched.h>
#include <linux/device.h>
#include <linux/poll.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/mutex.h>
#include <asm/sn/io.h>
#include <asm/sn/sn_sal.h>
#include <asm/sn/module.h>
#include <asm/sn/geo.h>
#include <asm/sn/nodepda.h>
#include "snsc.h"

#define SYSCTL_BASENAME	"snsc"

#define SCDRV_BUFSZ	2048
#define SCDRV_TIMEOUT	1000

static DEFINE_MUTEX(scdrv_mutex);
static irqreturn_t
scdrv_interrupt(int irq, void *subch_data)
{
	struct subch_data_s *sd = subch_data;
	unsigned long flags;
	int status;

	spin_lock_irqsave(&sd->sd_rlock, flags);
	spin_lock(&sd->sd_wlock);
	status = ia64_sn_irtr_intr(sd->sd_nasid, sd->sd_subch);

	if (status > 0) {
		if (status & SAL_IROUTER_INTR_RECV) {
			wake_up(&sd->sd_rq);
		}
		if (status & SAL_IROUTER_INTR_XMIT) {
			ia64_sn_irtr_intr_disable
			    (sd->sd_nasid, sd->sd_subch,
			     SAL_IROUTER_INTR_XMIT);
			wake_up(&sd->sd_wq);
		}
	}
	spin_unlock(&sd->sd_wlock);
	spin_unlock_irqrestore(&sd->sd_rlock, flags);
	return IRQ_HANDLED;
}

/*
 * scdrv_open
 *
 * Reserve a subchannel for system controller communication.
 */

static int
scdrv_open(struct inode *inode, struct file *file)
{
	struct sysctl_data_s *scd;
	struct subch_data_s *sd;
	int rv;

	/* look up device info for this device file */
	scd = container_of(inode->i_cdev, struct sysctl_data_s, scd_cdev);

	/* allocate memory for subchannel data */
	sd = kzalloc(sizeof (struct subch_data_s), GFP_KERNEL);
	if (sd == NULL) {
		printk("%s: couldn't allocate subchannel data\n",
		       __func__);
		return -ENOMEM;
	}

	/* initialize subch_data_s fields */
	sd->sd_nasid = scd->scd_nasid;
	sd->sd_subch = ia64_sn_irtr_open(scd->scd_nasid);

	if (sd->sd_subch < 0) {
		kfree(sd);
		printk("%s: couldn't allocate subchannel\n", __func__);
		return -EBUSY;
	}

	spin_lock_init(&sd->sd_rlock);
	spin_lock_init(&sd->sd_wlock);
	init_waitqueue_head(&sd->sd_rq);
	init_waitqueue_head(&sd->sd_wq);
	sema_init(&sd->sd_rbs, 1);
	sema_init(&sd->sd_wbs, 1);

	file->private_data = sd;

	/* hook this subchannel up to the system controller interrupt */
	mutex_lock(&scdrv_mutex);
	rv = request_irq(SGI_UART_VECTOR, scdrv_interrupt,
			 IRQF_SHARED | IRQF_DISABLED,
			 SYSCTL_BASENAME, sd);
	if (rv) {
		ia64_sn_irtr_close(sd->sd_nasid, sd->sd_subch);
		kfree(sd);
		printk("%s: irq request failed (%d)\n", __func__, rv);
		mutex_unlock(&scdrv_mutex);
		return -EBUSY;
	}
	mutex_unlock(&scdrv_mutex);
	return 0;
}

/*
 * scdrv_release
 *
 * Release a previously-reserved subchannel.
 */

static int
scdrv_release(struct inode *inode, struct file *file)
{
	struct subch_data_s *sd = (struct subch_data_s *) file->private_data;
	int rv;

	/* free the interrupt */
	free_irq(SGI_UART_VECTOR, sd);

	/* ask SAL to close the subchannel */
	rv = ia64_sn_irtr_close(sd->sd_nasid, sd->sd_subch);

	kfree(sd);
	return rv;
}

/*
 * scdrv_read
 *
 * Called to read bytes from the open IRouter pipe.
 *
 */

static inline int
read_status_check(struct subch_data_s *sd, int *len)
{
	return ia64_sn_irtr_recv(sd->sd_nasid, sd->sd_subch, sd->sd_rb, len);
}

static ssize_t
scdrv_read(struct file *file, char __user *buf, size_t count, loff_t *f_pos)
{
	int status;
	int len;
	unsigned long flags;
	struct subch_data_s *sd = (struct subch_data_s *) file->private_data;

	/* try to get control of the read buffer */
	if (down_trylock(&sd->sd_rbs)) {
		/* somebody else has it now;
		 * if we're non-blocking, then exit...
		 */
		if (file->f_flags & O_NONBLOCK) {
			return -EAGAIN;
		}
		/* ...or if we want to block, then do so here */
		if (down_interruptible(&sd->sd_rbs)) {
			/* something went wrong with wait */
			return -ERESTARTSYS;
		}
	}

	/* anything to read? */
	len = CHUNKSIZE;
	spin_lock_irqsave(&sd->sd_rlock, flags);
	status = read_status_check(sd, &len);

	/* if not, and we're blocking I/O, loop */
	while (status < 0) {
		DECLARE_WAITQUEUE(wait, current);

		if (file->f_flags & O_NONBLOCK) {
			spin_unlock_irqrestore(&sd->sd_rlock, flags);
			up(&sd->sd_rbs);
			return -EAGAIN;
		}

		len = CHUNKSIZE;
		set_current_state(TASK_INTERRUPTIBLE);
		add_wait_queue(&sd->sd_rq, &wait);
		spin_unlock_irqrestore(&sd->sd_rlock, flags);

		schedule_timeout(SCDRV_TIMEOUT);

		remove_wait_queue(&sd->sd_rq, &wait);
		if (signal_pending(current)) {
			/* wait was interrupted */
			up(&sd->sd_rbs);
			return -ERESTARTSYS;
		}

		spin_lock_irqsave(&sd->sd_rlock, flags);
		status = read_status_check(sd, &len);
	}
	spin_unlock_irqrestore(&sd->sd_rlock, flags);

	if (len > 0) {
		/* we read something in the last read_status_check(); copy
		 * it out to user space
		 */
		if (count < len) {
			pr_debug("%s: only accepting %d of %d bytes\n",
				 __func__, (int) count, len);
		}
		len = min((int) count, len);
		if (copy_to_user(buf, sd->sd_rb, len))
			len = -EFAULT;
	}

	/* release the read buffer and wake anyone who might be
	 * waiting for it
	 */
	up(&sd->sd_rbs);

	/* return the number of characters read in */
	return len;
}

/*
 * scdrv_write
 *
 * Writes a chunk of an IRouter packet (or other system controller data)
 * to the system controller.
 *
 */
static inline int
write_status_check(struct subch_data_s *sd, int count)
{
	return ia64_sn_irtr_send(sd->sd_nasid, sd->sd_subch, sd->sd_wb, count);
}

static ssize_t
scdrv_write(struct file *file, const char __user *buf,
	    size_t count, loff_t *f_pos)
{
	unsigned long flags;
	int status;
	struct subch_data_s *sd = (struct subch_data_s *) file->private_data;

	/* try to get control of the write buffer */
	if (down_trylock(&sd->sd_wbs)) {
		/* somebody else has it now;
		 * if we're non-blocking, then exit...
		 */
		if (file->f_flags & O_NONBLOCK) {
			return -EAGAIN;
		}
		/* ...or if we want to block, then do so here */
		if (down_interruptible(&sd->sd_wbs)) {
			/* something went wrong with wait */
			return -ERESTARTSYS;
		}
	}

	count = min((int) count, CHUNKSIZE);
	if (copy_from_user(sd->sd_wb, buf, count)) {
		up(&sd->sd_wbs);
		return -EFAULT;
	}

	/* try to send the buffer */
	spin_lock_irqsave(&sd->sd_wlock, flags);
	status = write_status_check(sd, count);

	/* if we failed, and we want to block, then loop */
	while (status <= 0) {
		DECLARE_WAITQUEUE(wait, current);

		if (file->f_flags & O_NONBLOCK) {
			spin_unlock(&sd->sd_wlock);
			up(&sd->sd_wbs);
			return -EAGAIN;
		}

		set_current_state(TASK_INTERRUPTIBLE);
		add_wait_queue(&sd->sd_wq, &wait);
		spin_unlock_irqrestore(&sd->sd_wlock, flags);

		schedule_timeout(SCDRV_TIMEOUT);

		remove_wait_queue(&sd->sd_wq, &wait);
		if (signal_pending(current)) {
			/* wait was interrupted */
			up(&sd->sd_wbs);
			return -ERESTARTSYS;
		}

		spin_lock_irqsave(&sd->sd_wlock, flags);
		status = write_status_check(sd, count);
	}
	spin_unlock_irqrestore(&sd->sd_wlock, flags);

	/* release the write buffer and wake anyone who's waiting for it */
	up(&sd->sd_wbs);

	/* return the number of characters accepted (should be the complete
	 * "chunk" as requested)
	 */
	if ((status >= 0) && (status < count)) {
		pr_debug("Didn't accept the full chunk; %d of %d\n",
			 status, (int) count);
	}
	return status;
}

static unsigned int
scdrv_poll(struct file *file, struct poll_table_struct *wait)
{
	unsigned int mask = 0;
	int status = 0;
	struct subch_data_s *sd = (struct subch_data_s *) file->private_data;
	unsigned long flags;

	poll_wait(file, &sd->sd_rq, wait);
	poll_wait(file, &sd->sd_wq, wait);

	spin_lock_irqsave(&sd->sd_rlock, flags);
	spin_lock(&sd->sd_wlock);
	status = ia64_sn_irtr_intr(sd->sd_nasid, sd->sd_subch);
	spin_unlock(&sd->sd_wlock);
	spin_unlock_irqrestore(&sd->sd_rlock, flags);

	if (status > 0) {
		if (status & SAL_IROUTER_INTR_RECV) {
			mask |= POLLIN | POLLRDNORM;
		}
		if (status & SAL_IROUTER_INTR_XMIT) {
			mask |= POLLOUT | POLLWRNORM;
		}
	}

	return mask;
}

static const struct file_operations scdrv_fops = {
	.owner =	THIS_MODULE,
	.read =		scdrv_read,
	.write =	scdrv_write,
	.poll =		scdrv_poll,
	.open =		scdrv_open,
	.release =	scdrv_release,
	.llseek =	noop_llseek,
};

static struct class *snsc_class;

/*
 * scdrv_init
 *
 * Called at boot time to initialize the system controller communication
 * facility.
 */
int __init
scdrv_init(void)
{
	geoid_t geoid;
	cnodeid_t cnode;
	char devname[32];
	char *devnamep;
	struct sysctl_data_s *scd;
	void *salbuf;
	dev_t first_dev, dev;
	nasid_t event_nasid;

	if (!ia64_platform_is("sn2"))
		return -ENODEV;

	event_nasid = ia64_sn_get_console_nasid();

	if (alloc_chrdev_region(&first_dev, 0, num_cnodes,
				SYSCTL_BASENAME) < 0) {
		printk("%s: failed to register SN system controller device\n",
		       __func__);
		return -ENODEV;
	}
	snsc_class = class_create(THIS_MODULE, SYSCTL_BASENAME);

	for (cnode = 0; cnode < num_cnodes; cnode++) {
			geoid = cnodeid_get_geoid(cnode);
			devnamep = devname;
			format_module_id(devnamep, geo_module(geoid),
					 MODULE_FORMAT_BRIEF);
			devnamep = devname + strlen(devname);
			sprintf(devnamep, "^%d#%d", geo_slot(geoid),
				geo_slab(geoid));

			/* allocate sysctl device data */
			scd = kzalloc(sizeof (struct sysctl_data_s),
				      GFP_KERNEL);
			if (!scd) {
				printk("%s: failed to allocate device info"
				       "for %s/%s\n", __func__,
				       SYSCTL_BASENAME, devname);
				continue;
			}

			/* initialize sysctl device data fields */
			scd->scd_nasid = cnodeid_to_nasid(cnode);
			if (!(salbuf = kmalloc(SCDRV_BUFSZ, GFP_KERNEL))) {
				printk("%s: failed to allocate driver buffer"
				       "(%s%s)\n", __func__,
				       SYSCTL_BASENAME, devname);
				kfree(scd);
				continue;
			}

			if (ia64_sn_irtr_init(scd->scd_nasid, salbuf,
					      SCDRV_BUFSZ) < 0) {
				printk
				    ("%s: failed to initialize SAL for"
				     " system controller communication"
				     " (%s/%s): outdated PROM?\n",
				     __func__, SYSCTL_BASENAME, devname);
				kfree(scd);
				kfree(salbuf);
				continue;
			}

			dev = first_dev + cnode;
			cdev_init(&scd->scd_cdev, &scdrv_fops);
			if (cdev_add(&scd->scd_cdev, dev, 1)) {
				printk("%s: failed to register system"
				       " controller device (%s%s)\n",
				       __func__, SYSCTL_BASENAME, devname);
				kfree(scd);
				kfree(salbuf);
				continue;
			}

			device_create(snsc_class, NULL, dev, NULL,
				      "%s", devname);

			ia64_sn_irtr_intr_enable(scd->scd_nasid,
						 0 /*ignored */ ,
						 SAL_IROUTER_INTR_RECV);

                        /* on the console nasid, prepare to receive
                         * system controller environmental events
                         */
                        if(scd->scd_nasid == event_nasid) {
                                scdrv_event_init(scd);
                        }
	}
	return 0;
}

module_init(scdrv_init);
Commit	Line	Data
1da177e4 LT	1	/*
	2	* SN Platform system controller communication support
	3	*
	4	* This file is subject to the terms and conditions of the GNU General Public
	5	* License. See the file "COPYING" in the main directory of this archive
	6	* for more details.
	7	*
40953ed8	8	* Copyright (C) 2004, 2006 Silicon Graphics, Inc. All rights reserved.
1da177e4 LT	9	*/
	10
	11	/*
	12	* System controller communication driver
	13	*
	14	* This driver allows a user process to communicate with the system
	15	* controller (a.k.a. "IRouter") network in an SGI SN system.
	16	*/
	17
	18	#include <linux/interrupt.h>
	19	#include <linux/sched.h>
	20	#include <linux/device.h>
	21	#include <linux/poll.h>
	22	#include <linux/module.h>
	23	#include <linux/slab.h>
613655fa	24	#include <linux/mutex.h>
1da177e4 LT	25	#include <asm/sn/io.h>
	26	#include <asm/sn/sn_sal.h>
	27	#include <asm/sn/module.h>
	28	#include <asm/sn/geo.h>
	29	#include <asm/sn/nodepda.h>
	30	#include "snsc.h"
	31
	32	#define SYSCTL_BASENAME "snsc"
	33
	34	#define SCDRV_BUFSZ 2048
	35	#define SCDRV_TIMEOUT 1000
	36
613655fa	37	static DEFINE_MUTEX(scdrv_mutex);
1da177e4	38	static irqreturn_t
7d12e780	39	scdrv_interrupt(int irq, void *subch_data)
1da177e4 LT	40	{
	41	struct subch_data_s *sd = subch_data;
	42	unsigned long flags;
	43	int status;
	44
	45	spin_lock_irqsave(&sd->sd_rlock, flags);
	46	spin_lock(&sd->sd_wlock);
	47	status = ia64_sn_irtr_intr(sd->sd_nasid, sd->sd_subch);
	48
	49	if (status > 0) {
	50	if (status & SAL_IROUTER_INTR_RECV) {
	51	wake_up(&sd->sd_rq);
	52	}
	53	if (status & SAL_IROUTER_INTR_XMIT) {
	54	ia64_sn_irtr_intr_disable
	55	(sd->sd_nasid, sd->sd_subch,
	56	SAL_IROUTER_INTR_XMIT);
	57	wake_up(&sd->sd_wq);
	58	}
	59	}
	60	spin_unlock(&sd->sd_wlock);
	61	spin_unlock_irqrestore(&sd->sd_rlock, flags);
	62	return IRQ_HANDLED;
	63	}
	64
	65	/*
	66	* scdrv_open
	67	*
	68	* Reserve a subchannel for system controller communication.
	69	*/
	70
	71	static int
	72	scdrv_open(struct inode inode, struct file file)
	73	{
	74	struct sysctl_data_s *scd;
	75	struct subch_data_s *sd;
	76	int rv;
	77
	78	/* look up device info for this device file */
	79	scd = container_of(inode->i_cdev, struct sysctl_data_s, scd_cdev);
	80
	81	/* allocate memory for subchannel data */
40953ed8	82	sd = kzalloc(sizeof (struct subch_data_s), GFP_KERNEL);
1da177e4 LT	83	if (sd == NULL) {
1da177e4 LT	84	printk("%s: couldn't allocate subchannel data\n",
bf9d8929	85	__func__);
1da177e4 LT	86	return -ENOMEM;
	87	}
	88
	89	/* initialize subch_data_s fields */
1da177e4 LT	90	sd->sd_nasid = scd->scd_nasid;
	91	sd->sd_subch = ia64_sn_irtr_open(scd->scd_nasid);
	92
	93	if (sd->sd_subch < 0) {
	94	kfree(sd);
bf9d8929	95	printk("%s: couldn't allocate subchannel\n", __func__);
1da177e4 LT	96	return -EBUSY;
	97	}
	98
	99	spin_lock_init(&sd->sd_rlock);
	100	spin_lock_init(&sd->sd_wlock);
	101	init_waitqueue_head(&sd->sd_rq);
	102	init_waitqueue_head(&sd->sd_wq);
	103	sema_init(&sd->sd_rbs, 1);
	104	sema_init(&sd->sd_wbs, 1);
	105
	106	file->private_data = sd;
	107
	108	/* hook this subchannel up to the system controller interrupt */
613655fa	109	mutex_lock(&scdrv_mutex);
1da177e4	110	rv = request_irq(SGI_UART_VECTOR, scdrv_interrupt,
0f2ed4c6	111	IRQF_SHARED \| IRQF_DISABLED,
1da177e4 LT	112	SYSCTL_BASENAME, sd);
	113	if (rv) {
	114	ia64_sn_irtr_close(sd->sd_nasid, sd->sd_subch);
	115	kfree(sd);
bf9d8929	116	printk("%s: irq request failed (%d)\n", __func__, rv);
613655fa	117	mutex_unlock(&scdrv_mutex);
1da177e4 LT	118	return -EBUSY;
1da177e4 LT	119	}
613655fa	120	mutex_unlock(&scdrv_mutex);
1da177e4 LT	121	return 0;
	122	}
	123
	124	/*
	125	* scdrv_release
	126	*
	127	* Release a previously-reserved subchannel.
	128	*/
	129
	130	static int
	131	scdrv_release(struct inode inode, struct file file)
	132	{
	133	struct subch_data_s sd = (struct subch_data_s ) file->private_data;
	134	int rv;
	135
	136	/* free the interrupt */
	137	free_irq(SGI_UART_VECTOR, sd);
	138
	139	/* ask SAL to close the subchannel */
	140	rv = ia64_sn_irtr_close(sd->sd_nasid, sd->sd_subch);
	141
	142	kfree(sd);
	143	return rv;
	144	}
	145
	146	/*
	147	* scdrv_read
	148	*
	149	* Called to read bytes from the open IRouter pipe.
	150	*
	151	*/
	152
	153	static inline int
	154	read_status_check(struct subch_data_s sd, int len)
	155	{
	156	return ia64_sn_irtr_recv(sd->sd_nasid, sd->sd_subch, sd->sd_rb, len);
	157	}
	158
	159	static ssize_t
	160	scdrv_read(struct file file, char __user buf, size_t count, loff_t *f_pos)
	161	{
	162	int status;
	163	int len;
	164	unsigned long flags;
	165	struct subch_data_s sd = (struct subch_data_s ) file->private_data;
	166
	167	/* try to get control of the read buffer */
	168	if (down_trylock(&sd->sd_rbs)) {
	169	/* somebody else has it now;
	170	* if we're non-blocking, then exit...
	171	*/
	172	if (file->f_flags & O_NONBLOCK) {
	173	return -EAGAIN;
	174	}
	175	/* ...or if we want to block, then do so here */
	176	if (down_interruptible(&sd->sd_rbs)) {
	177	/* something went wrong with wait */
	178	return -ERESTARTSYS;
	179	}
	180	}
	181
	182	/* anything to read? */
	183	len = CHUNKSIZE;
	184	spin_lock_irqsave(&sd->sd_rlock, flags);
185	status = read_status_check(sd, &len);
186
187	/* if not, and we're blocking I/O, loop */
188	while (status < 0) {
189	DECLARE_WAITQUEUE(wait, current);
190
191	if (file->f_flags & O_NONBLOCK) {
192	spin_unlock_irqrestore(&sd->sd_rlock, flags);
193	up(&sd->sd_rbs);
194	return -EAGAIN;
195	}
196
197	len = CHUNKSIZE;
198	set_current_state(TASK_INTERRUPTIBLE);
199	add_wait_queue(&sd->sd_rq, &wait);
200	spin_unlock_irqrestore(&sd->sd_rlock, flags);
201
202	schedule_timeout(SCDRV_TIMEOUT);
203
204	remove_wait_queue(&sd->sd_rq, &wait);
205	if (signal_pending(current)) {
206	/* wait was interrupted */
207	up(&sd->sd_rbs);
208	return -ERESTARTSYS;
209	}
210
211	spin_lock_irqsave(&sd->sd_rlock, flags);
212	status = read_status_check(sd, &len);
213	}
214	spin_unlock_irqrestore(&sd->sd_rlock, flags);
215
216	if (len > 0) {
217	/* we read something in the last read_status_check(); copy
218	* it out to user space
219	*/
220	if (count < len) {
221	pr_debug("%s: only accepting %d of %d bytes\n",
bf9d8929	222	__func__, (int) count, len);
1da177e4 LT	223	}
	224	len = min((int) count, len);
	225	if (copy_to_user(buf, sd->sd_rb, len))
	226	len = -EFAULT;
	227	}
	228
	229	/* release the read buffer and wake anyone who might be
	230	* waiting for it
	231	*/
	232	up(&sd->sd_rbs);
	233
	234	/* return the number of characters read in */
	235	return len;
	236	}
	237
	238	/*
	239	* scdrv_write
	240	*
	241	* Writes a chunk of an IRouter packet (or other system controller data)
	242	* to the system controller.
	243	*
	244	*/
	245	static inline int
	246	write_status_check(struct subch_data_s *sd, int count)
	247	{
	248	return ia64_sn_irtr_send(sd->sd_nasid, sd->sd_subch, sd->sd_wb, count);
	249	}
	250
	251	static ssize_t
	252	scdrv_write(struct file file, const char __user buf,
	253	size_t count, loff_t *f_pos)
	254	{
	255	unsigned long flags;
	256	int status;
	257	struct subch_data_s sd = (struct subch_data_s ) file->private_data;
	258
	259	/* try to get control of the write buffer */
	260	if (down_trylock(&sd->sd_wbs)) {
	261	/* somebody else has it now;
	262	* if we're non-blocking, then exit...
	263	*/
	264	if (file->f_flags & O_NONBLOCK) {
	265	return -EAGAIN;
	266	}
	267	/* ...or if we want to block, then do so here */
	268	if (down_interruptible(&sd->sd_wbs)) {
	269	/* something went wrong with wait */
	270	return -ERESTARTSYS;
	271	}
	272	}
	273
	274	count = min((int) count, CHUNKSIZE);
	275	if (copy_from_user(sd->sd_wb, buf, count)) {
	276	up(&sd->sd_wbs);
	277	return -EFAULT;
	278	}
	279
	280	/* try to send the buffer */
	281	spin_lock_irqsave(&sd->sd_wlock, flags);
	282	status = write_status_check(sd, count);
	283
	284	/* if we failed, and we want to block, then loop */
	285	while (status <= 0) {
	286	DECLARE_WAITQUEUE(wait, current);
287
288	if (file->f_flags & O_NONBLOCK) {
289	spin_unlock(&sd->sd_wlock);
290	up(&sd->sd_wbs);
291	return -EAGAIN;
292	}
293
294	set_current_state(TASK_INTERRUPTIBLE);
295	add_wait_queue(&sd->sd_wq, &wait);
296	spin_unlock_irqrestore(&sd->sd_wlock, flags);
297
298	schedule_timeout(SCDRV_TIMEOUT);
299
300	remove_wait_queue(&sd->sd_wq, &wait);
301	if (signal_pending(current)) {
302	/* wait was interrupted */
303	up(&sd->sd_wbs);
304	return -ERESTARTSYS;
305	}
306
307	spin_lock_irqsave(&sd->sd_wlock, flags);
308	status = write_status_check(sd, count);
309	}
310	spin_unlock_irqrestore(&sd->sd_wlock, flags);
311
312	/* release the write buffer and wake anyone who's waiting for it */
313	up(&sd->sd_wbs);
314
315	/* return the number of characters accepted (should be the complete
316	* "chunk" as requested)
317	*/
318	if ((status >= 0) && (status < count)) {
319	pr_debug("Didn't accept the full chunk; %d of %d\n",
320	status, (int) count);
321	}
322	return status;
323	}
324
325	static unsigned int
326	scdrv_poll(struct file file, struct poll_table_struct wait)
327	{
328	unsigned int mask = 0;
329	int status = 0;
330	struct subch_data_s sd = (struct subch_data_s ) file->private_data;
331	unsigned long flags;
332
333	poll_wait(file, &sd->sd_rq, wait);
334	poll_wait(file, &sd->sd_wq, wait);
335
336	spin_lock_irqsave(&sd->sd_rlock, flags);
337	spin_lock(&sd->sd_wlock);
338	status = ia64_sn_irtr_intr(sd->sd_nasid, sd->sd_subch);
339	spin_unlock(&sd->sd_wlock);
340	spin_unlock_irqrestore(&sd->sd_rlock, flags);
341
342	if (status > 0) {
343	if (status & SAL_IROUTER_INTR_RECV) {
344	mask \|= POLLIN \| POLLRDNORM;
345	}
346	if (status & SAL_IROUTER_INTR_XMIT) {
347	mask \|= POLLOUT \| POLLWRNORM;
348	}
349	}
350
351	return mask;
352	}
353
62322d25	354	static const struct file_operations scdrv_fops = {
1da177e4 LT	355	.owner = THIS_MODULE,
	356	.read = scdrv_read,
	357	.write = scdrv_write,
	358	.poll = scdrv_poll,
	359	.open = scdrv_open,
	360	.release = scdrv_release,
6038f373	361	.llseek = noop_llseek,
1da177e4 LT	362	};
1da177e4 LT	363
ca8eca68 GKH	364	static struct class *snsc_class;
ca8eca68 GKH	365
1da177e4 LT	366	/*
	367	* scdrv_init
	368	*
	369	* Called at boot time to initialize the system controller communication
	370	* facility.
	371	*/
	372	int __init
	373	scdrv_init(void)
	374	{
	375	geoid_t geoid;
	376	cnodeid_t cnode;
	377	char devname[32];
	378	char *devnamep;
	379	struct sysctl_data_s *scd;
	380	void *salbuf;
1da177e4	381	dev_t first_dev, dev;
c7c17423 GE	382	nasid_t event_nasid;
	383
	384	if (!ia64_platform_is("sn2"))
	385	return -ENODEV;
	386
	387	event_nasid = ia64_sn_get_console_nasid();
1da177e4	388
24ee0a6d	389	if (alloc_chrdev_region(&first_dev, 0, num_cnodes,
1da177e4 LT	390	SYSCTL_BASENAME) < 0) {
1da177e4 LT	391	printk("%s: failed to register SN system controller device\n",
bf9d8929	392	__func__);
1da177e4 LT	393	return -ENODEV;
1da177e4 LT	394	}
ca8eca68	395	snsc_class = class_create(THIS_MODULE, SYSCTL_BASENAME);
1da177e4	396
24ee0a6d	397	for (cnode = 0; cnode < num_cnodes; cnode++) {
1da177e4 LT	398	geoid = cnodeid_get_geoid(cnode);
	399	devnamep = devname;
	400	format_module_id(devnamep, geo_module(geoid),
	401	MODULE_FORMAT_BRIEF);
	402	devnamep = devname + strlen(devname);
8c4335a8	403	sprintf(devnamep, "^%d#%d", geo_slot(geoid),
8c4335a8	404	geo_slab(geoid));
1da177e4 LT	405
1da177e4 LT	406	/* allocate sysctl device data */
40953ed8	407	scd = kzalloc(sizeof (struct sysctl_data_s),
1da177e4 LT	408	GFP_KERNEL);
	409	if (!scd) {
	410	printk("%s: failed to allocate device info"
bf9d8929	411	"for %s/%s\n", __func__,
1da177e4 LT	412	SYSCTL_BASENAME, devname);
	413	continue;
	414	}
1da177e4 LT	415
	416	/* initialize sysctl device data fields */
	417	scd->scd_nasid = cnodeid_to_nasid(cnode);
	418	if (!(salbuf = kmalloc(SCDRV_BUFSZ, GFP_KERNEL))) {
	419	printk("%s: failed to allocate driver buffer"
bf9d8929	420	"(%s%s)\n", __func__,
1da177e4 LT	421	SYSCTL_BASENAME, devname);
	422	kfree(scd);
	423	continue;
	424	}
	425
	426	if (ia64_sn_irtr_init(scd->scd_nasid, salbuf,
	427	SCDRV_BUFSZ) < 0) {
	428	printk
	429	("%s: failed to initialize SAL for"
	430	" system controller communication"
	431	" (%s/%s): outdated PROM?\n",
bf9d8929	432	__func__, SYSCTL_BASENAME, devname);
1da177e4 LT	433	kfree(scd);
	434	kfree(salbuf);
	435	continue;
	436	}
	437
	438	dev = first_dev + cnode;
	439	cdev_init(&scd->scd_cdev, &scdrv_fops);
	440	if (cdev_add(&scd->scd_cdev, dev, 1)) {
	441	printk("%s: failed to register system"
	442	" controller device (%s%s)\n",
bf9d8929	443	__func__, SYSCTL_BASENAME, devname);
1da177e4 LT	444	kfree(scd);
	445	kfree(salbuf);
	446	continue;
	447	}
	448
03457cd4 GKH	449	device_create(snsc_class, NULL, dev, NULL,
03457cd4 GKH	450	"%s", devname);
1da177e4 LT	451
	452	ia64_sn_irtr_intr_enable(scd->scd_nasid,
	453	0 /ignored / ,
	454	SAL_IROUTER_INTR_RECV);
67639deb GH	455
	456	/* on the console nasid, prepare to receive
	457	* system controller environmental events
	458	*/
	459	if(scd->scd_nasid == event_nasid) {
	460	scdrv_event_init(scd);
	461	}
1da177e4 LT	462	}
	463	return 0;
	464	}
	465
	466	module_init(scdrv_init);