Linux-2.6.12-rc2v2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!

1 files changed, 1045 insertions, 0 deletions

diff --git a/drivers/block/acsi_slm.c b/drivers/block/acsi_slm.c
new file mode 100644
index 00000000000..e3be8c31a74
--- /dev/null
+++ b/drivers/block/acsi_slm.c
@@ -0,0 +1,1045 @@
+/*
+ * acsi_slm.c -- Device driver for the Atari SLM laser printer
+ *
+ * Copyright 1995 Roman Hodek <Roman.Hodek@informatik.uni-erlangen.de>
+ *
+ * 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.
+ * 
+ */
+
+/*
+
+Notes:
+
+The major number for SLM printers is 28 (like ACSI), but as a character
+device, not block device. The minor number is the number of the printer (if
+you have more than one SLM; currently max. 2 (#define-constant) SLMs are
+supported). The device can be opened for reading and writing. If reading it,
+you get some status infos (MODE SENSE data). Writing mode is used for the data
+to be printed. Some ioctls allow to get the printer status and to tune printer
+modes and some internal variables.
+
+A special problem of the SLM driver is the timing and thus the buffering of
+the print data. The problem is that all the data for one page must be present
+in memory when printing starts, else --when swapping occurs-- the timing could
+not be guaranteed. There are several ways to assure this:
+
+ 1) Reserve a buffer of 1196k (maximum page size) statically by
+    atari_stram_alloc(). The data are collected there until they're complete,
+	and then printing starts. Since the buffer is reserved, no further
+	considerations about memory and swapping are needed. So this is the
+	simplest method, but it needs a lot of memory for just the SLM.
+
+    An striking advantage of this method is (supposed the SLM_CONT_CNT_REPROG
+	method works, see there), that there are no timing problems with the DMA
+	anymore.
+	
+ 2) The other method would be to reserve the buffer dynamically each time
+    printing is required. I could think of looking at mem_map where the
+	largest unallocted ST-RAM area is, taking the area, and then extending it
+	by swapping out the neighbored pages, until the needed size is reached.
+	This requires some mm hacking, but seems possible. The only obstacle could
+	be pages that cannot be swapped out (reserved pages)...
+
+ 3) Another possibility would be to leave the real data in user space and to
+    work with two dribble buffers of about 32k in the driver: While the one
+	buffer is DMAed to the SLM, the other can be filled with new data. But
+	to keep the timing, that requires that the user data remain in memory and
+	are not swapped out. Requires mm hacking, too, but maybe not so bad as
+	method 2).
+
+*/
+
+#include <linux/module.h>
+
+#include <linux/errno.h>
+#include <linux/sched.h>
+#include <linux/timer.h>
+#include <linux/fs.h>
+#include <linux/major.h>
+#include <linux/kernel.h>
+#include <linux/delay.h>
+#include <linux/interrupt.h>
+#include <linux/time.h>
+#include <linux/mm.h>
+#include <linux/slab.h>
+#include <linux/devfs_fs_kernel.h>
+#include <linux/smp_lock.h>
+
+#include <asm/pgtable.h>
+#include <asm/system.h>
+#include <asm/uaccess.h>
+#include <asm/atarihw.h>
+#include <asm/atariints.h>
+#include <asm/atari_acsi.h>
+#include <asm/atari_stdma.h>
+#include <asm/atari_stram.h>
+#include <asm/atari_SLM.h>
+
+
+#undef	DEBUG
+
+/* Define this if the page data are continuous in physical memory. That
+ * requires less reprogramming of the ST-DMA */
+#define	SLM_CONTINUOUS_DMA
+
+/* Use continuous reprogramming of the ST-DMA counter register. This is
+ * --strictly speaking-- not allowed, Atari recommends not to look at the
+ * counter register while a DMA is going on. But I don't know if that applies
+ * only for reading the register, or also writing to it. Writing only works
+ * fine for me... The advantage is that the timing becomes absolutely
+ * uncritical: Just update each, say 200ms, the counter reg to its maximum,
+ * and the DMA will work until the status byte interrupt occurs.
+ */
+#define	SLM_CONT_CNT_REPROG
+
+#define CMDSET_TARG_LUN(cmd,targ,lun)			\
+    do {										\
+		cmd[0] = (cmd[0] & ~0xe0) | (targ)<<5;	\
+		cmd[1] = (cmd[1] & ~0xe0) | (lun)<<5;	\
+	} while(0)
+
+#define	START_TIMER(to)	mod_timer(&slm_timer, jiffies + (to))
+#define	STOP_TIMER()	del_timer(&slm_timer)
+
+
+static char slmreqsense_cmd[6] = { 0x03, 0, 0, 0, 0, 0 };
+static char slmprint_cmd[6]    = { 0x0a, 0, 0, 0, 0, 0 };
+static char slminquiry_cmd[6]  = { 0x12, 0, 0, 0, 0, 0x80 };
+static char slmmsense_cmd[6]   = { 0x1a, 0, 0, 0, 255, 0 };
+#if 0
+static char slmmselect_cmd[6]  = { 0x15, 0, 0, 0, 0, 0 };
+#endif
+
+
+#define	MAX_SLM		2
+
+static struct slm {
+	unsigned	target;			/* target number */
+	unsigned	lun;			/* LUN in target controller */
+	atomic_t	wr_ok; 			/* set to 0 if output part busy */
+	atomic_t	rd_ok;			/* set to 0 if status part busy */
+} slm_info[MAX_SLM];
+
+int N_SLM_Printers = 0;
+
+/* printer buffer */
+static unsigned char	*SLMBuffer;	/* start of buffer */
+static unsigned char	*BufferP;	/* current position in buffer */
+static int				BufferSize;	/* length of buffer for page size */
+
+typedef enum { IDLE, FILLING, PRINTING } SLMSTATE;
+static SLMSTATE			SLMState;
+static int				SLMBufOwner;	/* SLM# currently using the buffer */
+
+/* DMA variables */
+#ifndef SLM_CONT_CNT_REPROG
+static unsigned long	SLMCurAddr;		/* current base addr of DMA chunk */
+static unsigned long	SLMEndAddr;		/* expected end addr */
+static unsigned long	SLMSliceSize;	/* size of one DMA chunk */
+#endif
+static int				SLMError;
+
+/* wait queues */
+static DECLARE_WAIT_QUEUE_HEAD(slm_wait);	/* waiting for buffer */
+static DECLARE_WAIT_QUEUE_HEAD(print_wait);	/* waiting for printing finished */
+
+/* status codes */
+#define	SLMSTAT_OK		0x00
+#define	SLMSTAT_ORNERY	0x02
+#define	SLMSTAT_TONER	0x03
+#define	SLMSTAT_WARMUP	0x04
+#define	SLMSTAT_PAPER	0x05
+#define	SLMSTAT_DRUM	0x06
+#define	SLMSTAT_INJAM	0x07
+#define	SLMSTAT_THRJAM	0x08
+#define	SLMSTAT_OUTJAM	0x09
+#define	SLMSTAT_COVER	0x0a
+#define	SLMSTAT_FUSER	0x0b
+#define	SLMSTAT_IMAGER	0x0c
+#define	SLMSTAT_MOTOR	0x0d
+#define	SLMSTAT_VIDEO	0x0e
+#define	SLMSTAT_SYSTO	0x10
+#define	SLMSTAT_OPCODE	0x12
+#define	SLMSTAT_DEVNUM	0x15
+#define	SLMSTAT_PARAM	0x1a
+#define	SLMSTAT_ACSITO	0x1b	/* driver defined */
+#define	SLMSTAT_NOTALL	0x1c	/* driver defined */
+
+static char *SLMErrors[] = {
+	/* 0x00 */	"OK and ready",
+	/* 0x01 */	NULL,
+	/* 0x02 */	"ornery printer",
+	/* 0x03 */	"toner empty",
+	/* 0x04 */	"warming up",
+	/* 0x05 */	"paper empty",
+	/* 0x06 */	"drum empty",
+	/* 0x07 */	"input jam",
+	/* 0x08 */	"through jam",
+	/* 0x09 */	"output jam",
+	/* 0x0a */	"cover open",
+	/* 0x0b */	"fuser malfunction",
+	/* 0x0c */	"imager malfunction",
+	/* 0x0d */	"motor malfunction",
+	/* 0x0e */	"video malfunction",
+	/* 0x0f */	NULL,
+	/* 0x10 */	"printer system timeout",
+	/* 0x11 */	NULL,
+	/* 0x12 */	"invalid operation code",
+	/* 0x13 */	NULL,
+	/* 0x14 */	NULL,
+	/* 0x15 */	"invalid device number",
+	/* 0x16 */	NULL,
+	/* 0x17 */	NULL,
+	/* 0x18 */	NULL,
+	/* 0x19 */	NULL,
+	/* 0x1a */	"invalid parameter list",
+	/* 0x1b */	"ACSI timeout",
+	/* 0x1c */	"not all printed"
+};
+
+#define	N_ERRORS	(sizeof(SLMErrors)/sizeof(*SLMErrors))
+
+/* real (driver caused) error? */
+#define	IS_REAL_ERROR(x)	(x > 0x10)
+
+
+static struct {
+	char	*name;
+	int 	w, h;
+} StdPageSize[] = {
+	{ "Letter", 2400, 3180 },
+	{ "Legal",  2400, 4080 },
+	{ "A4",     2336, 3386 },
+	{ "B5",     2016, 2914 }
+};
+
+#define	N_STD_SIZES		(sizeof(StdPageSize)/sizeof(*StdPageSize))
+
+#define	SLM_BUFFER_SIZE	(2336*3386/8)	/* A4 for now */
+#define	SLM_DMA_AMOUNT	255				/* #sectors to program the DMA for */
+
+#ifdef	SLM_CONTINUOUS_DMA
+# define	SLM_DMA_INT_OFFSET	0		/* DMA goes until seccnt 0, no offs */
+# define	SLM_DMA_END_OFFSET	32		/* 32 Byte ST-DMA FIFO */
+# define	SLM_SLICE_SIZE(w) 	(255*512)
+#else
+# define	SLM_DMA_INT_OFFSET	32		/* 32 Byte ST-DMA FIFO */
+# define	SLM_DMA_END_OFFSET	32		/* 32 Byte ST-DMA FIFO */
+# define	SLM_SLICE_SIZE(w)	((254*512)/(w/8)*(w/8))
+#endif
+
+/* calculate the number of jiffies to wait for 'n' bytes */
+#ifdef SLM_CONT_CNT_REPROG
+#define	DMA_TIME_FOR(n)		50
+#define	DMA_STARTUP_TIME	0
+#else
+#define	DMA_TIME_FOR(n)		(n/1400-1)
+#define	DMA_STARTUP_TIME	650
+#endif
+
+/***************************** Prototypes *****************************/
+
+static char *slm_errstr( int stat );
+static int slm_getstats( char *buffer, int device );
+static ssize_t slm_read( struct file* file, char *buf, size_t count, loff_t
+                         *ppos );
+static void start_print( int device );
+static irqreturn_t slm_interrupt(int irc, void *data, struct pt_regs *fp);
+static void slm_test_ready( unsigned long dummy );
+static void set_dma_addr( unsigned long paddr );
+static unsigned long get_dma_addr( void );
+static ssize_t slm_write( struct file *file, const char *buf, size_t count,
+                          loff_t *ppos );
+static int slm_ioctl( struct inode *inode, struct file *file, unsigned int
+                      cmd, unsigned long arg );
+static int slm_open( struct inode *inode, struct file *file );
+static int slm_release( struct inode *inode, struct file *file );
+static int slm_req_sense( int device );
+static int slm_mode_sense( int device, char *buffer, int abs_flag );
+#if 0
+static int slm_mode_select( int device, char *buffer, int len, int
+                            default_flag );
+#endif
+static int slm_get_pagesize( int device, int *w, int *h );
+
+/************************* End of Prototypes **************************/
+
+
+static struct timer_list slm_timer = TIMER_INITIALIZER(slm_test_ready, 0, 0);
+
+static struct file_operations slm_fops = {
+	.owner =	THIS_MODULE,
+	.read =		slm_read,
+	.write =	slm_write,
+	.ioctl =	slm_ioctl,
+	.open =		slm_open,
+	.release =	slm_release,
+};
+
+
+/* ---------------------------------------------------------------------- */
+/*							   Status Functions							  */
+
+
+static char *slm_errstr( int stat )
+
+{	char *p;
+	static char	str[22];
+
+	stat &= 0x1f;
+	if (stat >= 0 && stat < N_ERRORS && (p = SLMErrors[stat]))
+		return( p );
+	sprintf( str, "unknown status 0x%02x", stat );
+	return( str );
+}
+
+
+static int slm_getstats( char *buffer, int device )
+
+{	int 			len = 0, stat, i, w, h;
+	unsigned char	buf[256];
+	
+	stat = slm_mode_sense( device, buf, 0 );
+	if (IS_REAL_ERROR(stat))
+		return( -EIO );
+	
+#define SHORTDATA(i)		((buf[i] << 8) | buf[i+1])
+#define	BOOLDATA(i,mask)	((buf[i] & mask) ? "on" : "off")
+
+	w = SHORTDATA( 3 );
+	h = SHORTDATA( 1 );
+		
+	len += sprintf( buffer+len, "Status\t\t%s\n",
+					slm_errstr( stat ) );
+	len += sprintf( buffer+len, "Page Size\t%dx%d",
+					w, h );
+
+	for( i = 0; i < N_STD_SIZES; ++i ) {
+		if (w == StdPageSize[i].w && h == StdPageSize[i].h)
+			break;
+	}
+	if (i < N_STD_SIZES)
+		len += sprintf( buffer+len, " (%s)", StdPageSize[i].name );
+	buffer[len++] = '\n';
+
+	len += sprintf( buffer+len, "Top/Left Margin\t%d/%d\n",
+					SHORTDATA( 5 ), SHORTDATA( 7 ) );
+	len += sprintf( buffer+len, "Manual Feed\t%s\n",
+					BOOLDATA( 9, 0x01 ) );
+	len += sprintf( buffer+len, "Input Select\t%d\n",
+					(buf[9] >> 1) & 7 );
+	len += sprintf( buffer+len, "Auto Select\t%s\n",
+					BOOLDATA( 9, 0x10 ) );
+	len += sprintf( buffer+len, "Prefeed Paper\t%s\n",
+					BOOLDATA( 9, 0x20 ) );
+	len += sprintf( buffer+len, "Thick Pixels\t%s\n",
+					BOOLDATA( 9, 0x40 ) );
+	len += sprintf( buffer+len, "H/V Resol.\t%d/%d dpi\n",
+					SHORTDATA( 12 ), SHORTDATA( 10 ) );
+	len += sprintf( buffer+len, "System Timeout\t%d\n",
+					buf[14] );
+	len += sprintf( buffer+len, "Scan Time\t%d\n",
+					SHORTDATA( 15 ) );
+	len += sprintf( buffer+len, "Page Count\t%d\n",
+					SHORTDATA( 17 ) );
+	len += sprintf( buffer+len, "In/Out Cap.\t%d/%d\n",
+					SHORTDATA( 19 ), SHORTDATA( 21 ) );
+	len += sprintf( buffer+len, "Stagger Output\t%s\n",
+					BOOLDATA( 23, 0x01 ) );
+	len += sprintf( buffer+len, "Output Select\t%d\n",
+					(buf[23] >> 1) & 7 );
+	len += sprintf( buffer+len, "Duplex Print\t%s\n",
+					BOOLDATA( 23, 0x10 ) );
+	len += sprintf( buffer+len, "Color Sep.\t%s\n",
+					BOOLDATA( 23, 0x20 ) );
+
+	return( len );
+}
+
+
+static ssize_t slm_read( struct file *file, char *buf, size_t count,
+						 loff_t *ppos )
+
+{
+	struct inode *node = file->f_dentry->d_inode;
+	unsigned long page;
+	int length;
+	int end;
+
+	if (count < 0)
+		return( -EINVAL );
+	if (!(page = __get_free_page( GFP_KERNEL )))
+		return( -ENOMEM );
+	
+	length = slm_getstats( (char *)page, iminor(node) );
+	if (length < 0) {
+		count = length;
+		goto out;
+	}
+	if (file->f_pos >= length) {
+		count = 0;
+		goto out;
+	}
+	if (count + file->f_pos > length)
+		count = length - file->f_pos;
+	end = count + file->f_pos;
+	if (copy_to_user(buf, (char *)page + file->f_pos, count)) {
+		count = -EFAULT;
+		goto out;
+	}
+	file->f_pos = end;
+out:	free_page( page );
+	return( count );
+}
+
+
+/* ---------------------------------------------------------------------- */
+/*								   Printing								  */
+
+
+static void start_print( int device )
+
+{	struct slm *sip = &slm_info[device];
+	unsigned char	*cmd;
+	unsigned long	paddr;
+	int				i;
+	
+	stdma_lock( slm_interrupt, NULL );
+
+	CMDSET_TARG_LUN( slmprint_cmd, sip->target, sip->lun );
+	cmd = slmprint_cmd;
+	paddr = virt_to_phys( SLMBuffer );
+	dma_cache_maintenance( paddr, virt_to_phys(BufferP)-paddr, 1 );
+	DISABLE_IRQ();
+
+	/* Low on A1 */
+	dma_wd.dma_mode_status = 0x88;
+	MFPDELAY();
+
+	/* send the command bytes except the last */
+	for( i = 0; i < 5; ++i ) {
+		DMA_LONG_WRITE( *cmd++, 0x8a );
+		udelay(20);
+		if (!acsi_wait_for_IRQ( HZ/2 )) {
+			SLMError = 1;
+			return; /* timeout */
+		}
+	}
+	/* last command byte */
+	DMA_LONG_WRITE( *cmd++, 0x82 );
+	MFPDELAY();
+	/* set DMA address */
+	set_dma_addr( paddr );
+	/* program DMA for write and select sector counter reg */
+	dma_wd.dma_mode_status = 0x192;
+	MFPDELAY();
+	/* program for 255*512 bytes and start DMA */
+	DMA_LONG_WRITE( SLM_DMA_AMOUNT, 0x112 );
+
+#ifndef SLM_CONT_CNT_REPROG
+	SLMCurAddr = paddr;
+	SLMEndAddr = paddr + SLMSliceSize + SLM_DMA_INT_OFFSET;
+#endif
+	START_TIMER( DMA_STARTUP_TIME + DMA_TIME_FOR( SLMSliceSize ));
+#if !defined(SLM_CONT_CNT_REPROG) && defined(DEBUG)
+	printk( "SLM: CurAddr=%#lx EndAddr=%#lx timer=%ld\n",
+			SLMCurAddr, SLMEndAddr, DMA_TIME_FOR( SLMSliceSize ) );
+#endif
+	
+	ENABLE_IRQ();
+}
+
+
+/* Only called when an error happened or at the end of a page */
+
+static irqreturn_t slm_interrupt(int irc, void *data, struct pt_regs *fp)
+
+{	unsigned long	addr;
+	int				stat;
+	
+	STOP_TIMER();
+	addr = get_dma_addr();
+	stat = acsi_getstatus();
+	SLMError = (stat < 0)             ? SLMSTAT_ACSITO :
+		       (addr < virt_to_phys(BufferP)) ? SLMSTAT_NOTALL :
+									    stat;
+
+	dma_wd.dma_mode_status = 0x80;
+	MFPDELAY();
+#ifdef DEBUG
+	printk( "SLM: interrupt, addr=%#lx, error=%d\n", addr, SLMError );
+#endif
+
+	wake_up( &print_wait );
+	stdma_release();
+	ENABLE_IRQ();
+	return IRQ_HANDLED;
+}
+
+
+static void slm_test_ready( unsigned long dummy )
+
+{
+#ifdef SLM_CONT_CNT_REPROG
+	/* program for 255*512 bytes again */
+	dma_wd.fdc_acces_seccount = SLM_DMA_AMOUNT;
+	START_TIMER( DMA_TIME_FOR(0) );
+#ifdef DEBUG
+	printk( "SLM: reprogramming timer for %d jiffies, addr=%#lx\n",
+			DMA_TIME_FOR(0), get_dma_addr() );
+#endif
+	
+#else /* !SLM_CONT_CNT_REPROG */
+
+	unsigned long	flags, addr;
+	int				d, ti;
+#ifdef DEBUG
+	struct timeval start_tm, end_tm;
+	int			   did_wait = 0;
+#endif
+
+	local_irq_save(flags);
+
+	addr = get_dma_addr();
+	if ((d = SLMEndAddr - addr) > 0) {
+		local_irq_restore(flags);
+		
+		/* slice not yet finished, decide whether to start another timer or to
+		 * busy-wait */
+		ti = DMA_TIME_FOR( d );
+		if (ti > 0) {
+#ifdef DEBUG
+			printk( "SLM: reprogramming timer for %d jiffies, rest %d bytes\n",
+					ti, d );
+#endif
+			START_TIMER( ti );
+			return;
+		}
+		/* wait for desired end address to be reached */
+#ifdef DEBUG
+		do_gettimeofday( &start_tm );
+		did_wait = 1;
+#endif
+		local_irq_disable();
+		while( get_dma_addr() < SLMEndAddr )
+			barrier();
+	}
+
+	/* slice finished, start next one */
+	SLMCurAddr += SLMSliceSize;
+
+#ifdef SLM_CONTINUOUS_DMA
+	/* program for 255*512 bytes again */
+	dma_wd.fdc_acces_seccount = SLM_DMA_AMOUNT;
+#else
+	/* set DMA address;
+	 * add 2 bytes for the ones in the SLM controller FIFO! */
+	set_dma_addr( SLMCurAddr + 2 );
+	/* toggle DMA to write and select sector counter reg */
+	dma_wd.dma_mode_status = 0x92;
+	MFPDELAY();
+	dma_wd.dma_mode_status = 0x192;
+	MFPDELAY();
+	/* program for 255*512 bytes and start DMA */
+	DMA_LONG_WRITE( SLM_DMA_AMOUNT, 0x112 );
+#endif
+	
+	local_irq_restore(flags);
+
+#ifdef DEBUG
+	if (did_wait) {
+		int ms;
+		do_gettimeofday( &end_tm );
+		ms = (end_tm.tv_sec*1000000+end_tm.tv_usec) -
+			 (start_tm.tv_sec*1000000+start_tm.tv_usec); 
+		printk( "SLM: did %ld.%ld ms busy waiting for %d bytes\n",
+				ms/1000, ms%1000, d );
+	}
+	else
+		printk( "SLM: didn't wait (!)\n" );
+#endif
+
+	if ((unsigned char *)PTOV( SLMCurAddr + SLMSliceSize ) >= BufferP) {
+		/* will be last slice, no timer necessary */
+#ifdef DEBUG
+		printk( "SLM: CurAddr=%#lx EndAddr=%#lx last slice -> no timer\n",
+				SLMCurAddr, SLMEndAddr );
+#endif
+	}
+	else {
+		/* not last slice */
+		SLMEndAddr = SLMCurAddr + SLMSliceSize + SLM_DMA_INT_OFFSET;
+		START_TIMER( DMA_TIME_FOR( SLMSliceSize ));
+#ifdef DEBUG
+		printk( "SLM: CurAddr=%#lx EndAddr=%#lx timer=%ld\n",
+				SLMCurAddr, SLMEndAddr, DMA_TIME_FOR( SLMSliceSize ) );
+#endif
+	}
+#endif /* SLM_CONT_CNT_REPROG */
+}
+
+
+static void set_dma_addr( unsigned long paddr )
+
+{	unsigned long flags;
+
+	local_irq_save(flags);
+	dma_wd.dma_lo = (unsigned char)paddr;
+	paddr >>= 8;
+	MFPDELAY();
+	dma_wd.dma_md = (unsigned char)paddr;
+	paddr >>= 8;
+	MFPDELAY();
+	if (ATARIHW_PRESENT( EXTD_DMA ))
+		st_dma_ext_dmahi = (unsigned short)paddr;
+	else
+		dma_wd.dma_hi = (unsigned char)paddr;
+	MFPDELAY();
+	local_irq_restore(flags);
+}
+
+
+static unsigned long get_dma_addr( void )
+
+{	unsigned long	addr;
+	
+	addr = dma_wd.dma_lo & 0xff;
+	MFPDELAY();
+	addr |= (dma_wd.dma_md & 0xff) << 8;
+	MFPDELAY();
+	addr |= (dma_wd.dma_hi & 0xff) << 16;
+	MFPDELAY();
+
+	return( addr );
+}
+
+
+static ssize_t slm_write( struct file *file, const char *buf, size_t count,
+						  loff_t *ppos )
+
+{
+	struct inode *node = file->f_dentry->d_inode;
+	int		device = iminor(node);
+	int		n, filled, w, h;
+
+	while( SLMState == PRINTING ||
+		   (SLMState == FILLING && SLMBufOwner != device) ) {
+		interruptible_sleep_on( &slm_wait );
+		if (signal_pending(current))
+			return( -ERESTARTSYS );
+	}
+	if (SLMState == IDLE) {
+		/* first data of page: get current page size  */
+		if (slm_get_pagesize( device, &w, &h ))
+			return( -EIO );
+		BufferSize = w*h/8;
+		if (BufferSize > SLM_BUFFER_SIZE)
+			return( -ENOMEM );
+
+		SLMState = FILLING;
+		SLMBufOwner = device;
+	}
+
+	n = count;
+	filled = BufferP - SLMBuffer;
+	if (filled + n > BufferSize)
+		n = BufferSize - filled;
+
+	if (copy_from_user(BufferP, buf, n))
+		return -EFAULT;
+	BufferP += n;
+	filled += n;
+
+	if (filled == BufferSize) {
+		/* Check the paper size again! The user may have switched it in the
+		 * time between starting the data and finishing them. Would end up in
+		 * a trashy page... */
+		if (slm_get_pagesize( device, &w, &h ))
+			return( -EIO );
+		if (BufferSize != w*h/8) {
+			printk( KERN_NOTICE "slm%d: page size changed while printing\n",
+					device );
+			return( -EAGAIN );
+		}
+
+		SLMState = PRINTING;
+		/* choose a slice size that is a multiple of the line size */
+#ifndef SLM_CONT_CNT_REPROG
+		SLMSliceSize = SLM_SLICE_SIZE(w);
+#endif
+		
+		start_print( device );
+		sleep_on( &print_wait );
+		if (SLMError && IS_REAL_ERROR(SLMError)) {
+			printk( KERN_ERR "slm%d: %s\n", device, slm_errstr(SLMError) );
+			n = -EIO;
+		}
+
+		SLMState = IDLE;
+		BufferP = SLMBuffer;
+		wake_up_interruptible( &slm_wait );
+	}
+	
+	return( n );
+}
+
+
+/* ---------------------------------------------------------------------- */
+/*							   ioctl Functions							  */
+
+
+static int slm_ioctl( struct inode *inode, struct file *file,
+					  unsigned int cmd, unsigned long arg )
+
+{	int		device = iminor(inode), err;
+	
+	/* I can think of setting:
+	 *  - manual feed
+	 *  - paper format
+	 *  - copy count
+	 *  - ...
+	 * but haven't implemented that yet :-)
+	 * BTW, has anybody better docs about the MODE SENSE/MODE SELECT data?
+	 */
+	switch( cmd ) {
+
+	  case SLMIORESET:		/* reset buffer, i.e. empty the buffer */
+		if (!(file->f_mode & 2))
+			return( -EINVAL );
+		if (SLMState == PRINTING)
+			return( -EBUSY );
+		SLMState = IDLE;
+		BufferP = SLMBuffer;
+		wake_up_interruptible( &slm_wait );
+		return( 0 );
+		
+	  case SLMIOGSTAT: {	/* get status */
+		int stat;
+		char *str;
+
+		stat = slm_req_sense( device );
+		if (arg) {
+			str = slm_errstr( stat );
+			if (put_user(stat,
+    	    	    	    	     (long *)&((struct SLM_status *)arg)->stat))
+    	    	    	    	return -EFAULT;
+			if (copy_to_user( ((struct SLM_status *)arg)->str, str,
+						 strlen(str) + 1))
+				return -EFAULT;
+		}
+		return( stat );
+	  }
+		
+	  case SLMIOGPSIZE: {	/* get paper size */
+		int w, h;
+		
+		if ((err = slm_get_pagesize( device, &w, &h ))) return( err );
+		
+    	    	if (put_user(w, (long *)&((struct SLM_paper_size *)arg)->width))
+			return -EFAULT;
+		if (put_user(h, (long *)&((struct SLM_paper_size *)arg)->height))
+			return -EFAULT;
+		return( 0 );
+	  }
+		
+	  case SLMIOGMFEED:	/* get manual feed */
+		return( -EINVAL );
+
+	  case SLMIOSPSIZE:	/* set paper size */
+		return( -EINVAL );
+
+	  case SLMIOSMFEED:	/* set manual feed */
+		return( -EINVAL );
+
+	}
+	return( -EINVAL );
+}
+
+
+/* ---------------------------------------------------------------------- */
+/*							 Opening and Closing						  */
+
+
+static int slm_open( struct inode *inode, struct file *file )
+
+{	int device;
+	struct slm *sip;
+	
+	device = iminor(inode);
+	if (device >= N_SLM_Printers)
+		return( -ENXIO );
+	sip = &slm_info[device];
+
+	if (file->f_mode & 2) {
+		/* open for writing is exclusive */
+		if ( !atomic_dec_and_test(&sip->wr_ok) ) {
+			atomic_inc(&sip->wr_ok);	
+			return( -EBUSY );
+		}
+	}
+	if (file->f_mode & 1) {
+		/* open for reading is exclusive */
+                if ( !atomic_dec_and_test(&sip->rd_ok) ) {
+                        atomic_inc(&sip->rd_ok);
+                        return( -EBUSY );
+                }
+	}
+
+	return( 0 );
+}
+
+
+static int slm_release( struct inode *inode, struct file *file )
+
+{	int device;
+	struct slm *sip;
+	
+	device = iminor(inode);
+	sip = &slm_info[device];
+
+	if (file->f_mode & 2)
+		atomic_inc( &sip->wr_ok );
+	if (file->f_mode & 1)
+		atomic_inc( &sip->rd_ok );
+	
+	return( 0 );
+}
+
+
+/* ---------------------------------------------------------------------- */
+/*						 ACSI Primitives for the SLM					  */
+
+
+static int slm_req_sense( int device )
+
+{	int			stat, rv;
+	struct slm *sip = &slm_info[device];
+	
+	stdma_lock( NULL, NULL );
+
+	CMDSET_TARG_LUN( slmreqsense_cmd, sip->target, sip->lun );
+	if (!acsicmd_nodma( slmreqsense_cmd, 0 ) ||
+		(stat = acsi_getstatus()) < 0)
+		rv = SLMSTAT_ACSITO;
+	else
+		rv = stat & 0x1f;
+
+	ENABLE_IRQ();
+	stdma_release();
+	return( rv );
+}
+
+
+static int slm_mode_sense( int device, char *buffer, int abs_flag )
+
+{	unsigned char	stat, len;
+	int				rv = 0;
+	struct slm		*sip = &slm_info[device];
+	
+	stdma_lock( NULL, NULL );
+
+	CMDSET_TARG_LUN( slmmsense_cmd, sip->target, sip->lun );
+	slmmsense_cmd[5] = abs_flag ? 0x80 : 0;
+	if (!acsicmd_nodma( slmmsense_cmd, 0 )) {
+		rv = SLMSTAT_ACSITO;
+		goto the_end;
+	}
+
+	if (!acsi_extstatus( &stat, 1 )) {
+		acsi_end_extstatus();
+		rv = SLMSTAT_ACSITO;
+		goto the_end;
+	}
+	
+	if (!acsi_extstatus( &len, 1 )) {
+		acsi_end_extstatus();
+		rv = SLMSTAT_ACSITO;
+		goto the_end;
+	}
+	buffer[0] = len;
+	if (!acsi_extstatus( buffer+1, len )) {
+		acsi_end_extstatus();
+		rv = SLMSTAT_ACSITO;
+		goto the_end;
+	}
+	
+	acsi_end_extstatus();
+	rv = stat & 0x1f;
+
+  the_end:
+	ENABLE_IRQ();
+	stdma_release();
+	return( rv );
+}
+
+
+#if 0
+/* currently unused */
+static int slm_mode_select( int device, char *buffer, int len,
+							int default_flag )
+
+{	int			stat, rv;
+	struct slm	*sip = &slm_info[device];
+	
+	stdma_lock( NULL, NULL );
+
+	CMDSET_TARG_LUN( slmmselect_cmd, sip->target, sip->lun );
+	slmmselect_cmd[5] = default_flag ? 0x80 : 0;
+	if (!acsicmd_nodma( slmmselect_cmd, 0 )) {
+		rv = SLMSTAT_ACSITO;
+		goto the_end;
+	}
+
+	if (!default_flag) {
+		unsigned char c = len;
+		if (!acsi_extcmd( &c, 1 )) {
+			rv = SLMSTAT_ACSITO;
+			goto the_end;
+		}
+		if (!acsi_extcmd( buffer, len )) {
+			rv = SLMSTAT_ACSITO;
+			goto the_end;
+		}
+	}
+	
+	stat = acsi_getstatus();
+	rv = (stat < 0 ? SLMSTAT_ACSITO : stat);
+
+  the_end:
+	ENABLE_IRQ();
+	stdma_release();
+	return( rv );
+}
+#endif
+
+
+static int slm_get_pagesize( int device, int *w, int *h )
+
+{	char	buf[256];
+	int		stat;
+	
+	stat = slm_mode_sense( device, buf, 0 );
+	ENABLE_IRQ();
+	stdma_release();
+
+	if (stat != SLMSTAT_OK)
+		return( -EIO );
+
+	*w = (buf[3] << 8) | buf[4];
+	*h = (buf[1] << 8) | buf[2];
+	return( 0 );
+}
+
+
+/* ---------------------------------------------------------------------- */
+/*								Initialization							  */
+
+
+int attach_slm( int target, int lun )
+
+{	static int	did_register;
+	int			len;
+
+	if (N_SLM_Printers >= MAX_SLM) {
+		printk( KERN_WARNING "Too much SLMs\n" );
+		return( 0 );
+	}
+	
+	/* do an INQUIRY */
+	udelay(100);
+	CMDSET_TARG_LUN( slminquiry_cmd, target, lun );
+	if (!acsicmd_nodma( slminquiry_cmd, 0 )) {
+	  inq_timeout:
+		printk( KERN_ERR "SLM inquiry command timed out.\n" );
+	  inq_fail:
+		acsi_end_extstatus();
+		return( 0 );
+	}
+	/* read status and header of return data */
+	if (!acsi_extstatus( SLMBuffer, 6 ))
+		goto inq_timeout;
+
+	if (SLMBuffer[1] != 2) { /* device type == printer? */
+		printk( KERN_ERR "SLM inquiry returned device type != printer\n" );
+		goto inq_fail;
+	}
+	len = SLMBuffer[5];
+	
+	/* read id string */
+	if (!acsi_extstatus( SLMBuffer, len ))
+		goto inq_timeout;
+	acsi_end_extstatus();
+	SLMBuffer[len] = 0;
+
+	if (!did_register) {
+		did_register = 1;
+	}
+
+	slm_info[N_SLM_Printers].target = target;
+	slm_info[N_SLM_Printers].lun    = lun;
+	atomic_set(&slm_info[N_SLM_Printers].wr_ok, 1 ); 
+	atomic_set(&slm_info[N_SLM_Printers].rd_ok, 1 );
+	
+	printk( KERN_INFO "  Printer: %s\n", SLMBuffer );
+	printk( KERN_INFO "Detected slm%d at id %d lun %d\n",
+			N_SLM_Printers, target, lun );
+	N_SLM_Printers++;
+	return( 1 );
+}
+
+int slm_init( void )
+
+{
+	int i;
+	if (register_chrdev( ACSI_MAJOR, "slm", &slm_fops )) {
+		printk( KERN_ERR "Unable to get major %d for ACSI SLM\n", ACSI_MAJOR );
+		return -EBUSY;
+	}
+	
+	if (!(SLMBuffer = atari_stram_alloc( SLM_BUFFER_SIZE, "SLM" ))) {
+		printk( KERN_ERR "Unable to get SLM ST-Ram buffer.\n" );
+		unregister_chrdev( ACSI_MAJOR, "slm" );
+		return -ENOMEM;
+	}
+	BufferP = SLMBuffer;
+	SLMState = IDLE;
+	
+	devfs_mk_dir("slm");
+	for (i = 0; i < MAX_SLM; i++) {
+		devfs_mk_cdev(MKDEV(ACSI_MAJOR, i),
+				S_IFCHR|S_IRUSR|S_IWUSR, "slm/%d", i);
+	}
+	return 0;
+}
+
+#ifdef MODULE
+
+/* from acsi.c */
+void acsi_attach_SLMs( int (*attach_func)( int, int ) );
+
+int init_module(void)
+{
+	int err;
+
+	if ((err = slm_init()))
+		return( err );
+	/* This calls attach_slm() for every target/lun where acsi.c detected a
+	 * printer */
+	acsi_attach_SLMs( attach_slm );
+	return( 0 );
+}
+
+void cleanup_module(void)
+{
+	int i;
+	for (i = 0; i < MAX_SLM; i++)
+		devfs_remove("slm/%d", i);
+	devfs_remove("slm");
+	if (unregister_chrdev( ACSI_MAJOR, "slm" ) != 0)
+		printk( KERN_ERR "acsi_slm: cleanup_module failed\n");
+	atari_stram_free( SLMBuffer );
+}
+#endif