Merge with /home/shaggy/git/linus-clean/

8 files changed, 251 insertions, 225 deletions

diff --git a/drivers/parport/Kconfig b/drivers/parport/Kconfig
index 725a14119f2..f605dea5722 100644
--- a/drivers/parport/Kconfig
+++ b/drivers/parport/Kconfig
@@ -34,7 +34,7 @@ config PARPORT
 
 config PARPORT_PC
 	tristate "PC-style hardware"
-	depends on PARPORT && (!SPARC64 || PCI) && !SPARC32 && !M32R
+	depends on PARPORT && (!SPARC64 || PCI) && !SPARC32 && !M32R && !FRV
 	---help---
 	  You should say Y here if you have a PC-style parallel port. All
 	  IBM PC compatible computers and some Alphas have PC-style
@@ -77,7 +77,7 @@ config PARPORT_PC_SUPERIO
 
 config PARPORT_PC_PCMCIA
 	tristate "Support for PCMCIA management for PC-style ports"
-	depends on PARPORT!=n && (PCMCIA!=n && PARPORT_PC=m && PARPORT_PC || PARPORT_PC=y && PCMCIA)
+	depends on PCMCIA && PARPORT_PC
 	help
 	  Say Y here if you need PCMCIA support for your PC-style parallel
 	  ports. If unsure, say N.
@@ -121,6 +121,7 @@ config PARPORT_GSC
 	tristate
 	default GSC
 	depends on PARPORT
+	select PARPORT_NOT_PC
 
 config PARPORT_SUNBPP
 	tristate "Sparc hardware (EXPERIMENTAL)"
diff --git a/drivers/parport/daisy.c b/drivers/parport/daisy.c
index 075c7eb5c85..9ee67321b63 100644
--- a/drivers/parport/daisy.c
+++ b/drivers/parport/daisy.c
@@ -144,9 +144,9 @@ again:
 	add_dev (numdevs++, port, -1);
 
 	/* Find out the legacy device's IEEE 1284 device ID. */
-	deviceid = kmalloc (1000, GFP_KERNEL);
+	deviceid = kmalloc (1024, GFP_KERNEL);
 	if (deviceid) {
-		if (parport_device_id (numdevs - 1, deviceid, 1000) > 2)
+		if (parport_device_id (numdevs - 1, deviceid, 1024) > 2)
 			detected++;
 
 		kfree (deviceid);
@@ -252,7 +252,7 @@ struct pardevice *parport_open (int devnum, const char *name,
 		selected = port->daisy;
 		parport_release (dev);
 
-		if (selected != port->daisy) {
+		if (selected != daisy) {
 			/* No corresponding device. */
 			parport_unregister_device (dev);
 			return NULL;
@@ -344,9 +344,9 @@ static int cpp_daisy (struct parport *port, int cmd)
 			      PARPORT_CONTROL_STROBE,
 			      PARPORT_CONTROL_STROBE);
 	udelay (1);
+	s = parport_read_status (port);
 	parport_frob_control (port, PARPORT_CONTROL_STROBE, 0);
 	udelay (1);
-	s = parport_read_status (port);
 	parport_write_data (port, 0xff); udelay (2);
 
 	return s;
@@ -395,15 +395,15 @@ int parport_daisy_select (struct parport *port, int daisy, int mode)
 		case IEEE1284_MODE_EPP:
 		case IEEE1284_MODE_EPPSL:
 		case IEEE1284_MODE_EPPSWE:
-			return (cpp_daisy (port, 0x20 + daisy) &
-				PARPORT_STATUS_ERROR);
+			return !(cpp_daisy (port, 0x20 + daisy) &
+				 PARPORT_STATUS_ERROR);
 
 		// For these modes we should switch to ECP mode:
 		case IEEE1284_MODE_ECP:
 		case IEEE1284_MODE_ECPRLE:
 		case IEEE1284_MODE_ECPSWE: 
-			return (cpp_daisy (port, 0xd0 + daisy) &
-				PARPORT_STATUS_ERROR);
+			return !(cpp_daisy (port, 0xd0 + daisy) &
+				 PARPORT_STATUS_ERROR);
 
 		// Nothing was told for BECP in Daisy chain specification.
 		// May be it's wise to use ECP?
@@ -413,8 +413,8 @@ int parport_daisy_select (struct parport *port, int daisy, int mode)
 		case IEEE1284_MODE_BYTE:
 		case IEEE1284_MODE_COMPAT:
 		default:
-			return (cpp_daisy (port, 0xe0 + daisy) &
-				PARPORT_STATUS_ERROR);
+			return !(cpp_daisy (port, 0xe0 + daisy) &
+				 PARPORT_STATUS_ERROR);
 	}
 }
 
@@ -436,7 +436,7 @@ static int select_port (struct parport *port)
 
 static int assign_addrs (struct parport *port)
 {
-	unsigned char s, last_dev;
+	unsigned char s;
 	unsigned char daisy;
 	int thisdev = numdevs;
 	int detected;
@@ -472,10 +472,13 @@ static int assign_addrs (struct parport *port)
 	}
 
 	parport_write_data (port, 0x78); udelay (2);
-	last_dev = 0; /* We've just been speaking to a device, so we
-			 know there must be at least _one_ out there. */
+	s = parport_read_status (port);
 
-	for (daisy = 0; daisy < 4; daisy++) {
+	for (daisy = 0;
+	     (s & (PARPORT_STATUS_PAPEROUT|PARPORT_STATUS_SELECT))
+		     == (PARPORT_STATUS_PAPEROUT|PARPORT_STATUS_SELECT)
+		     && daisy < 4;
+	     ++daisy) {
 		parport_write_data (port, daisy);
 		udelay (2);
 		parport_frob_control (port,
@@ -485,14 +488,18 @@ static int assign_addrs (struct parport *port)
 		parport_frob_control (port, PARPORT_CONTROL_STROBE, 0);
 		udelay (1);
 
-		if (last_dev)
-			/* No more devices. */
-			break;
+		add_dev (numdevs++, port, daisy);
 
-		last_dev = !(parport_read_status (port)
-			     & PARPORT_STATUS_BUSY);
+		/* See if this device thought it was the last in the
+		 * chain. */
+		if (!(s & PARPORT_STATUS_BUSY))
+			break;
 
-		add_dev (numdevs++, port, daisy);
+		/* We are seeing pass through status now. We see
+		   last_dev from next device or if last_dev does not
+		   work status lines from some non-daisy chain
+		   device. */
+		s = parport_read_status (port);
 	}
 
 	parport_write_data (port, 0xff); udelay (2);
@@ -501,11 +508,11 @@ static int assign_addrs (struct parport *port)
 		 detected);
 
 	/* Ask the new devices to introduce themselves. */
-	deviceid = kmalloc (1000, GFP_KERNEL);
+	deviceid = kmalloc (1024, GFP_KERNEL);
 	if (!deviceid) return 0;
 
 	for (daisy = 0; thisdev < numdevs; thisdev++, daisy++)
-		parport_device_id (thisdev, deviceid, 1000);
+		parport_device_id (thisdev, deviceid, 1024);
 
 	kfree (deviceid);
 	return detected;
diff --git a/drivers/parport/ieee1284_ops.c b/drivers/parport/ieee1284_ops.c
index ce1e2aad8b1..d6c77658231 100644
--- a/drivers/parport/ieee1284_ops.c
+++ b/drivers/parport/ieee1284_ops.c
@@ -165,17 +165,7 @@ size_t parport_ieee1284_read_nibble (struct parport *port,
 		/* Does the error line indicate end of data? */
 		if (((i & 1) == 0) &&
 		    (parport_read_status(port) & PARPORT_STATUS_ERROR)) {
-			port->physport->ieee1284.phase = IEEE1284_PH_HBUSY_DNA;
-			DPRINTK (KERN_DEBUG
-				"%s: No more nibble data (%d bytes)\n",
-				port->name, i/2);
-
-			/* Go to reverse idle phase. */
-			parport_frob_control (port,
-					      PARPORT_CONTROL_AUTOFD,
-					      PARPORT_CONTROL_AUTOFD);
-			port->physport->ieee1284.phase = IEEE1284_PH_REV_IDLE;
-			break;
+			goto end_of_data;
 		}
 
 		/* Event 7: Set nAutoFd low. */
@@ -225,18 +215,25 @@ size_t parport_ieee1284_read_nibble (struct parport *port,
 			byte = nibble;
 	}
 
-	i /= 2; /* i is now in bytes */
-
 	if (i == len) {
 		/* Read the last nibble without checking data avail. */
-		port = port->physport;
-		if (parport_read_status (port) & PARPORT_STATUS_ERROR)
-			port->ieee1284.phase = IEEE1284_PH_HBUSY_DNA;
+		if (parport_read_status (port) & PARPORT_STATUS_ERROR) {
+		end_of_data:
+			DPRINTK (KERN_DEBUG
+				"%s: No more nibble data (%d bytes)\n",
+				port->name, i/2);
+
+			/* Go to reverse idle phase. */
+			parport_frob_control (port,
+					      PARPORT_CONTROL_AUTOFD,
+					      PARPORT_CONTROL_AUTOFD);
+			port->physport->ieee1284.phase = IEEE1284_PH_REV_IDLE;
+		}
 		else
-			port->ieee1284.phase = IEEE1284_PH_HBUSY_DAVAIL;
+			port->physport->ieee1284.phase = IEEE1284_PH_HBUSY_DAVAIL;
 	}
 
-	return i;
+	return i/2;
 #endif /* IEEE1284 support */
 }
 
@@ -256,17 +253,7 @@ size_t parport_ieee1284_read_byte (struct parport *port,
 
 		/* Data available? */
 		if (parport_read_status (port) & PARPORT_STATUS_ERROR) {
-			port->physport->ieee1284.phase = IEEE1284_PH_HBUSY_DNA;
-			DPRINTK (KERN_DEBUG
-				 "%s: No more byte data (%Zd bytes)\n",
-				 port->name, count);
-
-			/* Go to reverse idle phase. */
-			parport_frob_control (port,
-					      PARPORT_CONTROL_AUTOFD,
-					      PARPORT_CONTROL_AUTOFD);
-			port->physport->ieee1284.phase = IEEE1284_PH_REV_IDLE;
-			break;
+			goto end_of_data;
 		}
 
 		/* Event 14: Place data bus in high impedance state. */
@@ -318,11 +305,20 @@ size_t parport_ieee1284_read_byte (struct parport *port,
 
 	if (count == len) {
 		/* Read the last byte without checking data avail. */
-		port = port->physport;
-		if (parport_read_status (port) & PARPORT_STATUS_ERROR)
-			port->ieee1284.phase = IEEE1284_PH_HBUSY_DNA;
+		if (parport_read_status (port) & PARPORT_STATUS_ERROR) {
+		end_of_data:
+			DPRINTK (KERN_DEBUG
+				 "%s: No more byte data (%Zd bytes)\n",
+				 port->name, count);
+
+			/* Go to reverse idle phase. */
+			parport_frob_control (port,
+					      PARPORT_CONTROL_AUTOFD,
+					      PARPORT_CONTROL_AUTOFD);
+			port->physport->ieee1284.phase = IEEE1284_PH_REV_IDLE;
+		}
 		else
-			port->ieee1284.phase = IEEE1284_PH_HBUSY_DAVAIL;
+			port->physport->ieee1284.phase = IEEE1284_PH_HBUSY_DAVAIL;
 	}
 
 	return count;
diff --git a/drivers/parport/parport_cs.c b/drivers/parport/parport_cs.c
index 24e6aacddb7..158d9256325 100644
--- a/drivers/parport/parport_cs.c
+++ b/drivers/parport/parport_cs.c
@@ -87,15 +87,9 @@ typedef struct parport_info_t {
     struct parport	*port;
 } parport_info_t;
 
-static dev_link_t *parport_attach(void);
-static void parport_detach(dev_link_t *);
+static void parport_detach(struct pcmcia_device *p_dev);
 static void parport_config(dev_link_t *link);
 static void parport_cs_release(dev_link_t *);
-static int parport_event(event_t event, int priority,
-			 event_callback_args_t *args);
-
-static dev_info_t dev_info = "parport_cs";
-static dev_link_t *dev_list = NULL;
 
 /*======================================================================
 
@@ -105,18 +99,16 @@ static dev_link_t *dev_list = NULL;
 
 ======================================================================*/
 
-static dev_link_t *parport_attach(void)
+static int parport_attach(struct pcmcia_device *p_dev)
 {
     parport_info_t *info;
     dev_link_t *link;
-    client_reg_t client_reg;
-    int ret;
-    
+
     DEBUG(0, "parport_attach()\n");
 
     /* Create new parport device */
     info = kmalloc(sizeof(*info), GFP_KERNEL);
-    if (!info) return NULL;
+    if (!info) return -ENOMEM;
     memset(info, 0, sizeof(*info));
     link = &info->link; link->priv = info;
 
@@ -127,21 +119,14 @@ static dev_link_t *parport_attach(void)
     link->conf.Attributes = CONF_ENABLE_IRQ;
     link->conf.Vcc = 50;
     link->conf.IntType = INT_MEMORY_AND_IO;
-    
-    /* Register with Card Services */
-    link->next = dev_list;
-    dev_list = link;
-    client_reg.dev_info = &dev_info;
-    client_reg.Version = 0x0210;
-    client_reg.event_callback_args.client_data = link;
-    ret = pcmcia_register_client(&link->handle, &client_reg);
-    if (ret != CS_SUCCESS) {
-	cs_error(link->handle, RegisterClient, ret);
-	parport_detach(link);
-	return NULL;
-    }
-    
-    return link;
+
+    link->handle = p_dev;
+    p_dev->instance = link;
+
+    link->state |= DEV_PRESENT | DEV_CONFIG_PENDING;
+    parport_config(link);
+
+    return 0;
 } /* parport_attach */
 
 /*======================================================================
@@ -153,32 +138,16 @@ static dev_link_t *parport_attach(void)
 
 ======================================================================*/
 
-static void parport_detach(dev_link_t *link)
+static void parport_detach(struct pcmcia_device *p_dev)
 {
-    dev_link_t **linkp;
-    int ret;
+    dev_link_t *link = dev_to_instance(p_dev);
 
     DEBUG(0, "parport_detach(0x%p)\n", link);
-    
-    /* Locate device structure */
-    for (linkp = &dev_list; *linkp; linkp = &(*linkp)->next)
-	if (*linkp == link) break;
-    if (*linkp == NULL)
-	return;
 
     if (link->state & DEV_CONFIG)
 	parport_cs_release(link);
-    
-    if (link->handle) {
-	ret = pcmcia_deregister_client(link->handle);
-	if (ret != CS_SUCCESS)
-	    cs_error(link->handle, DeregisterClient, ret);
-    }
-    
-    /* Unlink, free device structure */
-    *linkp = link->next;
+
     kfree(link->priv);
-    
 } /* parport_detach */
 
 /*======================================================================
@@ -325,47 +294,27 @@ void parport_cs_release(dev_link_t *link)
 
 } /* parport_cs_release */
 
-/*======================================================================
-
-    The card status event handler.  Mostly, this schedules other
-    stuff to run after an event is received.
-    
-======================================================================*/
-
-int parport_event(event_t event, int priority,
-		  event_callback_args_t *args)
+static int parport_suspend(struct pcmcia_device *dev)
 {
-    dev_link_t *link = args->client_data;
+	dev_link_t *link = dev_to_instance(dev);
 
-    DEBUG(1, "parport_event(0x%06x)\n", event);
-    
-    switch (event) {
-    case CS_EVENT_CARD_REMOVAL:
-	link->state &= ~DEV_PRESENT;
-	if (link->state & DEV_CONFIG)
-		parport_cs_release(link);
-	break;
-    case CS_EVENT_CARD_INSERTION:
-	link->state |= DEV_PRESENT | DEV_CONFIG_PENDING;
-	parport_config(link);
-	break;
-    case CS_EVENT_PM_SUSPEND:
 	link->state |= DEV_SUSPEND;
-	/* Fall through... */
-    case CS_EVENT_RESET_PHYSICAL:
 	if (link->state & DEV_CONFIG)
-	    pcmcia_release_configuration(link->handle);
-	break;
-    case CS_EVENT_PM_RESUME:
+		pcmcia_release_configuration(link->handle);
+
+	return 0;
+}
+
+static int parport_resume(struct pcmcia_device *dev)
+{
+	dev_link_t *link = dev_to_instance(dev);
+
 	link->state &= ~DEV_SUSPEND;
-	/* Fall through... */
-    case CS_EVENT_CARD_RESET:
 	if (DEV_OK(link))
-	    pcmcia_request_configuration(link->handle, &link->conf);
-	break;
-    }
-    return 0;
-} /* parport_event */
+		pcmcia_request_configuration(link->handle, &link->conf);
+
+	return 0;
+}
 
 static struct pcmcia_device_id parport_ids[] = {
 	PCMCIA_DEVICE_FUNC_ID(3),
@@ -379,11 +328,11 @@ static struct pcmcia_driver parport_cs_driver = {
 	.drv		= {
 		.name	= "parport_cs",
 	},
-	.attach		= parport_attach,
-	.event		= parport_event,
-	.detach		= parport_detach,
+	.probe		= parport_attach,
+	.remove		= parport_detach,
 	.id_table	= parport_ids,
-
+	.suspend	= parport_suspend,
+	.resume		= parport_resume,
 };
 
 static int __init init_parport_cs(void)
@@ -394,7 +343,6 @@ static int __init init_parport_cs(void)
 static void __exit exit_parport_cs(void)
 {
 	pcmcia_unregister_driver(&parport_cs_driver);
-	BUG_ON(dev_list != NULL);
 }
 
 module_init(init_parport_cs);
diff --git a/drivers/parport/parport_pc.c b/drivers/parport/parport_pc.c
index c6493ad7c0c..9302b8fd746 100644
--- a/drivers/parport/parport_pc.c
+++ b/drivers/parport/parport_pc.c
@@ -1169,7 +1169,7 @@ dump_parport_state ("fwd idle", port);
 
 /* GCC is not inlining extern inline function later overwriten to non-inline,
    so we use outlined_ variants here.  */
-static struct parport_operations parport_pc_ops =
+static const struct parport_operations parport_pc_ops =
 {
 	.write_data	= parport_pc_write_data,
 	.read_data	= parport_pc_read_data,
@@ -1211,10 +1211,11 @@ static struct parport_operations parport_pc_ops =
 static void __devinit show_parconfig_smsc37c669(int io, int key)
 {
 	int cr1,cr4,cra,cr23,cr26,cr27,i=0;
-	static const char *modes[]={ "SPP and Bidirectional (PS/2)",	
-				     "EPP and SPP",
-				     "ECP",
-				     "ECP and EPP" };
+	static const char *const modes[]={
+		"SPP and Bidirectional (PS/2)",
+		"EPP and SPP",
+		"ECP",
+		"ECP and EPP" };
 
 	outb(key,io);
 	outb(key,io);
@@ -1288,7 +1289,7 @@ static void __devinit show_parconfig_smsc37c669(int io, int key)
 static void __devinit show_parconfig_winbond(int io, int key)
 {
 	int cr30,cr60,cr61,cr70,cr74,crf0,i=0;
-	static const char *modes[] = {
+	static const char *const modes[] = {
 		"Standard (SPP) and Bidirectional(PS/2)", /* 0 */
 		"EPP-1.9 and SPP",
 		"ECP",
@@ -1297,7 +1298,9 @@ static void __devinit show_parconfig_winbond(int io, int key)
 		"EPP-1.7 and SPP",		/* 5 */
 		"undefined!",
 		"ECP and EPP-1.7" };
-	static char *irqtypes[] = { "pulsed low, high-Z", "follows nACK" };
+	static char *const irqtypes[] = {
+		"pulsed low, high-Z",
+		"follows nACK" };
 		
 	/* The registers are called compatible-PnP because the
            register layout is modelled after ISA-PnP, the access
@@ -2368,8 +2371,10 @@ void parport_pc_unregister_port (struct parport *p)
 	spin_lock(&ports_lock);
 	list_del_init(&priv->list);
 	spin_unlock(&ports_lock);
+#if defined(CONFIG_PARPORT_PC_FIFO) && defined(HAS_DMA)
 	if (p->dma != PARPORT_DMA_NONE)
 		free_dma(p->dma);
+#endif
 	if (p->irq != PARPORT_IRQ_NONE)
 		free_irq(p->irq, p);
 	release_region(p->base, 3);
@@ -2377,14 +2382,12 @@ void parport_pc_unregister_port (struct parport *p)
 		release_region(p->base + 3, p->size - 3);
 	if (p->modes & PARPORT_MODE_ECP)
 		release_region(p->base_hi, 3);
-#ifdef CONFIG_PARPORT_PC_FIFO
-#ifdef HAS_DMA
+#if defined(CONFIG_PARPORT_PC_FIFO) && defined(HAS_DMA)
 	if (priv->dma_buf)
 		pci_free_consistent(priv->dev, PAGE_SIZE,
 				    priv->dma_buf,
 				    priv->dma_handle);
 #endif
-#endif
 	kfree (p->private_data);
 	parport_put_port(p);
 	kfree (ops); /* hope no-one cached it */
@@ -2396,7 +2399,8 @@ EXPORT_SYMBOL (parport_pc_unregister_port);
 
 /* ITE support maintained by Rich Liu <richliu@poorman.org> */
 static int __devinit sio_ite_8872_probe (struct pci_dev *pdev, int autoirq,
-					 int autodma, struct parport_pc_via_data *via)
+					 int autodma,
+					 const struct parport_pc_via_data *via)
 {
 	short inta_addr[6] = { 0x2A0, 0x2C0, 0x220, 0x240, 0x1E0 };
 	struct resource *base_res;
@@ -2524,7 +2528,8 @@ static struct parport_pc_via_data via_8231_data __devinitdata = {
 };
 
 static int __devinit sio_via_probe (struct pci_dev *pdev, int autoirq,
-					 int autodma, struct parport_pc_via_data *via)
+				    int autodma,
+				    const struct parport_pc_via_data *via)
 {
 	u8 tmp, tmp2, siofunc;
 	u8 ppcontrol = 0;
@@ -2694,8 +2699,9 @@ enum parport_pc_sio_types {
 
 /* each element directly indexed from enum list, above */
 static struct parport_pc_superio {
-	int (*probe) (struct pci_dev *pdev, int autoirq, int autodma, struct parport_pc_via_data *via);
-	struct parport_pc_via_data *via;
+	int (*probe) (struct pci_dev *pdev, int autoirq, int autodma,
+		      const struct parport_pc_via_data *via);
+	const struct parport_pc_via_data *via;
 } parport_pc_superio_info[] __devinitdata = {
 	{ sio_via_probe, &via_686a_data, },
 	{ sio_via_probe, &via_8231_data, },
@@ -2828,7 +2834,7 @@ static struct parport_pc_pci {
 	/* netmos_9815 */               { 2, { { 0, -1 }, { 2, -1 }, } }, /* untested */
 };
 
-static struct pci_device_id parport_pc_pci_tbl[] = {
+static const struct pci_device_id parport_pc_pci_tbl[] = {
 	/* Super-IO onboard chips */
 	{ 0x1106, 0x0686, PCI_ANY_ID, PCI_ANY_ID, 0, 0, sio_via_686a },
 	{ 0x1106, 0x8231, PCI_ANY_ID, PCI_ANY_ID, 0, 0, sio_via_8231 },
diff --git a/drivers/parport/parport_serial.c b/drivers/parport/parport_serial.c
index d3dad0aac7c..76dd077e318 100644
--- a/drivers/parport/parport_serial.c
+++ b/drivers/parport/parport_serial.c
@@ -464,7 +464,7 @@ static struct pci_driver parport_serial_pci_driver = {
 
 static int __init parport_serial_init (void)
 {
-	return pci_module_init (&parport_serial_pci_driver);
+	return pci_register_driver (&parport_serial_pci_driver);
 }
 
 static void __exit parport_serial_exit (void)
diff --git a/drivers/parport/probe.c b/drivers/parport/probe.c
index 4b48b31ec23..b62aee8de3c 100644
--- a/drivers/parport/probe.c
+++ b/drivers/parport/probe.c
@@ -11,9 +11,9 @@
 #include <linux/string.h>
 #include <asm/uaccess.h>
 
-static struct {
-	char *token;
-	char *descr;
+static const struct {
+	const char *token;
+	const char *descr;
 } classes[] = {
 	{ "",            "Legacy device" },
 	{ "PRINTER",     "Printer" },
@@ -128,8 +128,131 @@ static void parse_data(struct parport *port, int device, char *str)
 	kfree(txt);
 }
 
+/* Read up to count-1 bytes of device id. Terminate buffer with
+ * '\0'. Buffer begins with two Device ID length bytes as given by
+ * device. */
+static ssize_t parport_read_device_id (struct parport *port, char *buffer,
+				       size_t count)
+{
+	unsigned char length[2];
+	unsigned lelen, belen;
+	size_t idlens[4];
+	unsigned numidlens;
+	unsigned current_idlen;
+	ssize_t retval;
+	size_t len;
+
+	/* First two bytes are MSB,LSB of inclusive length. */
+	retval = parport_read (port, length, 2);
+
+	if (retval < 0)
+		return retval;
+	if (retval != 2)
+		return -EIO;
+
+	if (count < 2)
+		return 0;
+	memcpy(buffer, length, 2);
+	len = 2;
+
+	/* Some devices wrongly send LE length, and some send it two
+	 * bytes short. Construct a sorted array of lengths to try. */
+	belen = (length[0] << 8) + length[1];
+	lelen = (length[1] << 8) + length[0];
+	idlens[0] = min(belen, lelen);
+	idlens[1] = idlens[0]+2;
+	if (belen != lelen) {
+		int off = 2;
+		/* Don't try lenghts of 0x100 and 0x200 as 1 and 2 */
+		if (idlens[0] <= 2)
+			off = 0;
+		idlens[off] = max(belen, lelen);
+		idlens[off+1] = idlens[off]+2;
+		numidlens = off+2;
+	}
+	else {
+		/* Some devices don't truly implement Device ID, but
+		 * just return constant nibble forever. This catches
+		 * also those cases. */
+		if (idlens[0] == 0 || idlens[0] > 0xFFF) {
+			printk (KERN_DEBUG "%s: reported broken Device ID"
+				" length of %#zX bytes\n",
+				port->name, idlens[0]);
+			return -EIO;
+		}
+		numidlens = 2;
+	}
+
+	/* Try to respect the given ID length despite all the bugs in
+	 * the ID length. Read according to shortest possible ID
+	 * first. */
+	for (current_idlen = 0; current_idlen < numidlens; ++current_idlen) {
+		size_t idlen = idlens[current_idlen];
+		if (idlen+1 >= count)
+			break;
+
+		retval = parport_read (port, buffer+len, idlen-len);
+
+		if (retval < 0)
+			return retval;
+		len += retval;
+
+		if (port->physport->ieee1284.phase != IEEE1284_PH_HBUSY_DAVAIL) {
+			if (belen != len) {
+				printk (KERN_DEBUG "%s: Device ID was %d bytes"
+					" while device told it would be %d"
+					" bytes\n",
+					port->name, len, belen);
+			}
+			goto done;
+		}
+
+		/* This might end reading the Device ID too
+		 * soon. Hopefully the needed fields were already in
+		 * the first 256 bytes or so that we must have read so
+		 * far. */
+		if (buffer[len-1] == ';') {
+ 			printk (KERN_DEBUG "%s: Device ID reading stopped"
+				" before device told data not available. "
+				"Current idlen %d of %d, len bytes %02X %02X\n",
+				port->name, current_idlen, numidlens,
+				length[0], length[1]);
+			goto done;
+		}
+	}
+	if (current_idlen < numidlens) {
+		/* Buffer not large enough, read to end of buffer. */
+		size_t idlen, len2;
+		if (len+1 < count) {
+			retval = parport_read (port, buffer+len, count-len-1);
+			if (retval < 0)
+				return retval;
+			len += retval;
+		}
+		/* Read the whole ID since some devices would not
+		 * otherwise give back the Device ID from beginning
+		 * next time when asked. */
+		idlen = idlens[current_idlen];
+		len2 = len;
+		while(len2 < idlen && retval > 0) {
+			char tmp[4];
+			retval = parport_read (port, tmp,
+					       min(sizeof tmp, idlen-len2));
+			if (retval < 0)
+				return retval;
+			len2 += retval;
+		}
+	}
+	/* In addition, there are broken devices out there that don't
+	   even finish off with a semi-colon. We do not need to care
+	   about those at this time. */
+ done:
+	buffer[len] = '\0';
+	return len;
+}
+
 /* Get Std 1284 Device ID. */
-ssize_t parport_device_id (int devnum, char *buffer, size_t len)
+ssize_t parport_device_id (int devnum, char *buffer, size_t count)
 {
 	ssize_t retval = -ENXIO;
 	struct pardevice *dev = parport_open (devnum, "Device ID probe",
@@ -139,76 +262,20 @@ ssize_t parport_device_id (int devnum, char *buffer, size_t len)
 
 	parport_claim_or_block (dev);
 
-	/* Negotiate to compatibility mode, and then to device ID mode.
-	 * (This is in case we are already in device ID mode.) */
+	/* Negotiate to compatibility mode, and then to device ID
+	 * mode. (This so that we start form beginning of device ID if
+	 * already in device ID mode.) */
 	parport_negotiate (dev->port, IEEE1284_MODE_COMPAT);
 	retval = parport_negotiate (dev->port,
 				    IEEE1284_MODE_NIBBLE | IEEE1284_DEVICEID);
 
 	if (!retval) {
-		int idlen;
-		unsigned char length[2];
-
-		/* First two bytes are MSB,LSB of inclusive length. */
-		retval = parport_read (dev->port, length, 2);
-
-		if (retval != 2) goto end_id;
-
-		idlen = (length[0] << 8) + length[1] - 2;
-		/*
-		 * Check if the caller-allocated buffer is large enough
-		 * otherwise bail out or there will be an at least off by one.
-		 */
-		if (idlen + 1 < len)
-			len = idlen;
-		else {
-			retval = -EINVAL;
-			goto out;
-		}
-		retval = parport_read (dev->port, buffer, len);
-
-		if (retval != len)
-			printk (KERN_DEBUG "%s: only read %Zd of %Zd ID bytes\n",
-				dev->port->name, retval,
-				len);
-
-		/* Some printer manufacturers mistakenly believe that
-                   the length field is supposed to be _exclusive_.
-		   In addition, there are broken devices out there
-                   that don't even finish off with a semi-colon. */
-		if (buffer[len - 1] != ';') {
-			ssize_t diff;
-			diff = parport_read (dev->port, buffer + len, 2);
-			retval += diff;
-
-			if (diff)
-				printk (KERN_DEBUG
-					"%s: device reported incorrect "
-					"length field (%d, should be %Zd)\n",
-					dev->port->name, idlen, retval);
-			else {
-				/* One semi-colon short of a device ID. */
-				buffer[len++] = ';';
-				printk (KERN_DEBUG "%s: faking semi-colon\n",
-					dev->port->name);
-
-				/* If we get here, I don't think we
-                                   need to worry about the possible
-                                   standard violation of having read
-                                   more than we were told to.  The
-                                   device is non-compliant anyhow. */
-			}
-		}
-
-	end_id:
-		buffer[len] = '\0';
+		retval = parport_read_device_id (dev->port, buffer, count);
 		parport_negotiate (dev->port, IEEE1284_MODE_COMPAT);
+		if (retval > 2)
+			parse_data (dev->port, dev->daisy, buffer+2);
 	}
 
-	if (retval > 2)
-		parse_data (dev->port, dev->daisy, buffer);
-
-out:
 	parport_release (dev);
 	parport_close (dev);
 	return retval;
diff --git a/drivers/parport/share.c b/drivers/parport/share.c
index 9cb3ab156b0..ea62bed6bc8 100644
--- a/drivers/parport/share.c
+++ b/drivers/parport/share.c
@@ -1002,6 +1002,7 @@ EXPORT_SYMBOL(parport_register_driver);
 EXPORT_SYMBOL(parport_unregister_driver);
 EXPORT_SYMBOL(parport_register_device);
 EXPORT_SYMBOL(parport_unregister_device);
+EXPORT_SYMBOL(parport_get_port);
 EXPORT_SYMBOL(parport_put_port);
 EXPORT_SYMBOL(parport_find_number);
 EXPORT_SYMBOL(parport_find_base);