Merge tag 'staging-4.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging

Pull staging and IIO updates from Greg KH:
 "Here is the big staging and IIO driver pull request for 4.9-rc1.

  There are a lot of patches in here, the majority due to the
  drivers/staging/greybus/ subsystem being merged in with full
  development history that went back a few years, in order to preserve
  the work that those developers did over time.

  Lots and lots of tiny cleanups happened in the tree as well, due to
  the Outreachy application process and lots of other developers showing
  up for the first time to clean code up.  Along with those changes, we
  deleted a wireless driver, and added a raspberrypi driver (currently
  marked broken), and lots of new iio drivers.

  Overall the tree still shrunk with more lines removed than added,
  about 10 thousand lines removed in total. Full details are in the very
  long shortlog below.

  All of this has been in the linux-next tree with no issues. There will
  be some merge problems with other subsystem trees, but those are all
  minor problems and shouldn't be hard to work out when they happen
  (MAINTAINERS and some lustre build problems with the IB tree)"

And furter from me asking for clarification about greybus:
 "Right now there is a phone from Motorola shipping with this code (a
  slightly older version, but the same tree), so even though Ara is not
  alive in the same form, the functionality is happening. We are working
  with the developers of that phone to merge the newer stuff in with
  their fork so they can use the upstream version in future versions of
  their phone product line.

  Toshiba has at least one chip shipping in their catalog that
  needs/uses this protocol over a Unipro link, and rumor has it that
  there might be more in the future.

  There are also other users of the greybus protocols, there is a talk
  next week at ELC that shows how it is being used across a network
  connection to control a device, and previous ELC talks have showed the
  protocol stack being used over USB to drive embedded Linux boards.
  I've also talked to some people who are starting to work to add a host
  controller driver to control arduinos as the greybus PHY protocols are
  very useful to control a serial/i2c/spio/whatever device across a
  random physical link, as it is a way to have a self-describing device
  be attached to a host without needing manual configuration.

  So yes, people are using it, and there is still the chance that it
  will show up in a phone/laptop/tablet/whatever from Google in the
  future as well, the tech isn't dead, even if the original large phone
  project happens to be"

* tag 'staging-4.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging: (3703 commits)
  Staging: fbtft: Fix bug in fbtft-core
  staging: rtl8188eu: fix double unlock error in rtw_resume_process()
  staging:r8188eu: remove GEN_MLME_EXT_HANDLER macro
  staging:r8188eu: remove GEN_DRV_CMD_HANDLER macro
  staging:r8188eu: remove GEN_EVT_CODE macro
  staging:r8188eu: remove GEN_CMD_CODE macro
  staging:r8188eu: remove pkt_newalloc member of the recv_buf structure
  staging:r8188eu: remove rtw_handle_dualmac declaration
  staging:r8188eu: remove (RGTRY|BSSID)_(OFT|SZ) macros
  staging:r8188eu: change rtl8188e_process_phy_info function argument type
  Staging: fsl-mc: Remove blank lines
  Staging: fsl-mc: Fix unaligned * in block comments
  Staging: comedi: Align the * in block comments
  Staging : ks7010 : Fix block comments warninig
  Staging: vt6655: Remove explicit NULL comparison using Coccinelle
  staging: rtl8188eu: core: rtw_xmit: Use macros instead of constants
  staging: rtl8188eu: core: rtw_xmit: Move constant of the right side
  staging: dgnc: Fix lines longer than 80 characters
  Staging: dgnc: constify attribute_group structures
  Staging: most: hdm-dim2: constify attribute_group structures
  ...

1 files changed, 752 insertions, 841 deletions

diff --git a/drivers/staging/unisys/visorbus/visorchipset.c b/drivers/staging/unisys/visorbus/visorchipset.c
index d248c94..5987149 100644
--- a/drivers/staging/unisys/visorbus/visorchipset.c
+++ b/drivers/staging/unisys/visorbus/visorchipset.c
@@ -25,21 +25,12 @@
 #include <linux/uuid.h>
 #include <linux/crash_dump.h>
 
-#include "channel_guid.h"
-#include "controlvmchannel.h"
-#include "controlvmcompletionstatus.h"
-#include "guestlinuxdebug.h"
-#include "periodic_work.h"
-#include "version.h"
 #include "visorbus.h"
 #include "visorbus_private.h"
 #include "vmcallinterface.h"
 
 #define CURRENT_FILE_PC VISOR_CHIPSET_PC_visorchipset_main_c
 
-#define MAX_NAME_SIZE 128
-#define MAX_IP_SIZE   50
-#define MAXOUTSTANDINGCHANNELCOMMAND 256
 #define POLLJIFFIES_CONTROLVMCHANNEL_FAST   1
 #define POLLJIFFIES_CONTROLVMCHANNEL_SLOW 100
 
@@ -58,9 +49,6 @@
  * Module parameters
  */
 static int visorchipset_major;
-static int visorchipset_visorbusregwait = 1;	/* default is on */
-static unsigned long controlvm_payload_bytes_buffered;
-static u32 dump_vhba_bus;
 
 static int
 visorchipset_open(struct inode *inode, struct file *file)
@@ -79,15 +67,15 @@ visorchipset_release(struct inode *inode, struct file *file)
 	return 0;
 }
 
-/* When the controlvm channel is idle for at least MIN_IDLE_SECONDS,
-* we switch to slow polling mode.  As soon as we get a controlvm
-* message, we switch back to fast polling mode.
-*/
+/*
+ * When the controlvm channel is idle for at least MIN_IDLE_SECONDS,
+ * we switch to slow polling mode. As soon as we get a controlvm
+ * message, we switch back to fast polling mode.
+ */
 #define MIN_IDLE_SECONDS 10
 static unsigned long poll_jiffies = POLLJIFFIES_CONTROLVMCHANNEL_FAST;
 /* when we got our last controlvm message */
 static unsigned long most_recent_message_jiffies;
-static int visorbusregistered;
 
 struct parser_context {
 	unsigned long allocbytes;
@@ -99,51 +87,36 @@ struct parser_context {
 };
 
 static struct delayed_work periodic_controlvm_work;
-static DEFINE_SEMAPHORE(notifier_lock);
 
 static struct cdev file_cdev;
 static struct visorchannel **file_controlvm_channel;
-static struct controlvm_message_packet g_devicechangestate_packet;
-
-static LIST_HEAD(bus_info_list);
-static LIST_HEAD(dev_info_list);
 
 static struct visorchannel *controlvm_channel;
 
 /* Manages the request payload in the controlvm channel */
 struct visor_controlvm_payload_info {
 	u8 *ptr;		/* pointer to base address of payload pool */
-	u64 offset;		/* offset from beginning of controlvm
+	u64 offset;		/*
+				 * offset from beginning of controlvm
 				 * channel to beginning of payload * pool
 				 */
 	u32 bytes;		/* number of bytes in payload pool */
 };
 
 static struct visor_controlvm_payload_info controlvm_payload_info;
+static unsigned long controlvm_payload_bytes_buffered;
 
-/* The following globals are used to handle the scenario where we are unable to
- * offload the payload from a controlvm message due to memory requirements.  In
+/*
+ * The following globals are used to handle the scenario where we are unable to
+ * offload the payload from a controlvm message due to memory requirements. In
  * this scenario, we simply stash the controlvm message, then attempt to
  * process it again the next time controlvm_periodic_work() runs.
  */
 static struct controlvm_message controlvm_pending_msg;
 static bool controlvm_pending_msg_valid;
 
-/* This identifies a data buffer that has been received via a controlvm messages
- * in a remote --> local CONTROLVM_TRANSMIT_FILE conversation.
- */
-struct putfile_buffer_entry {
-	struct list_head next;	/* putfile_buffer_entry list */
-	struct parser_context *parser_ctx; /* points to input data buffer */
-};
-
-/* List of struct putfile_request *, via next_putfile_request member.
- * Each entry in this list identifies an outstanding TRANSMIT_FILE
- * conversation.
- */
-static LIST_HEAD(putfile_request_list);
-
-/* This describes a buffer and its current state of transfer (e.g., how many
+/*
+ * This describes a buffer and its current state of transfer (e.g., how many
  * bytes have already been supplied as putfile data, and how many bytes are
  * remaining) for a putfile_request.
  */
@@ -155,8 +128,9 @@ struct putfile_active_buffer {
 };
 
 #define PUTFILE_REQUEST_SIG 0x0906101302281211
-/* This identifies a single remote --> local CONTROLVM_TRANSMIT_FILE
- * conversation.  Structs of this type are dynamically linked into
+/*
+ * This identifies a single remote --> local CONTROLVM_TRANSMIT_FILE
+ * conversation. Structs of this type are dynamically linked into
  * <Putfile_request_list>.
  */
 struct putfile_request {
@@ -168,7 +142,8 @@ struct putfile_request {
 	/* link to next struct putfile_request */
 	struct list_head next_putfile_request;
 
-	/* head of putfile_buffer_entry list, which describes the data to be
+	/*
+	 * head of putfile_buffer_entry list, which describes the data to be
 	 * supplied as putfile data;
 	 * - this list is added to when controlvm messages come in that supply
 	 * file data
@@ -184,11 +159,13 @@ struct putfile_request {
 	/* data not yet read within current putfile_buffer_entry */
 	struct putfile_active_buffer active_buf;
 
-	/* <0 = failed, 0 = in-progress, >0 = successful; */
-	/* note that this must be set with req_list_lock, and if you set <0, */
-	/* it is your responsibility to also free up all of the other objects */
-	/* in this struct (like input_buffer_list, active_buf.parser_ctx) */
-	/* before releasing the lock */
+	/*
+	 * <0 = failed, 0 = in-progress, >0 = successful;
+	 * note that this must be set with req_list_lock, and if you set <0,
+	 * it is your responsibility to also free up all of the other objects
+	 * in this struct (like input_buffer_list, active_buf.parser_ctx)
+	 * before releasing the lock
+	 */
 	int completion_status;
 };
 
@@ -199,289 +176,11 @@ struct parahotplug_request {
 	struct controlvm_message msg;
 };
 
-static LIST_HEAD(parahotplug_request_list);
-static DEFINE_SPINLOCK(parahotplug_request_list_lock);	/* lock for above */
-static void parahotplug_process_list(void);
-
-/* Manages the info for a CONTROLVM_DUMP_CAPTURESTATE /
- * CONTROLVM_REPORTEVENT.
- */
-static struct visorchipset_busdev_notifiers busdev_notifiers;
-
-static void bus_create_response(struct visor_device *p, int response);
-static void bus_destroy_response(struct visor_device *p, int response);
-static void device_create_response(struct visor_device *p, int response);
-static void device_destroy_response(struct visor_device *p, int response);
-static void device_resume_response(struct visor_device *p, int response);
-
-static void visorchipset_device_pause_response(struct visor_device *p,
-					       int response);
-
-static struct visorchipset_busdev_responders busdev_responders = {
-	.bus_create = bus_create_response,
-	.bus_destroy = bus_destroy_response,
-	.device_create = device_create_response,
-	.device_destroy = device_destroy_response,
-	.device_pause = visorchipset_device_pause_response,
-	.device_resume = device_resume_response,
-};
-
 /* info for /dev/visorchipset */
-static dev_t major_dev = -1; /**< indicates major num for device */
+static dev_t major_dev = -1; /*< indicates major num for device */
 
 /* prototypes for attributes */
 static ssize_t toolaction_show(struct device *dev,
-			       struct device_attribute *attr, char *buf);
-static ssize_t toolaction_store(struct device *dev,
-				struct device_attribute *attr,
-				const char *buf, size_t count);
-static DEVICE_ATTR_RW(toolaction);
-
-static ssize_t boottotool_show(struct device *dev,
-			       struct device_attribute *attr, char *buf);
-static ssize_t boottotool_store(struct device *dev,
-				struct device_attribute *attr, const char *buf,
-				size_t count);
-static DEVICE_ATTR_RW(boottotool);
-
-static ssize_t error_show(struct device *dev, struct device_attribute *attr,
-			  char *buf);
-static ssize_t error_store(struct device *dev, struct device_attribute *attr,
-			   const char *buf, size_t count);
-static DEVICE_ATTR_RW(error);
-
-static ssize_t textid_show(struct device *dev, struct device_attribute *attr,
-			   char *buf);
-static ssize_t textid_store(struct device *dev, struct device_attribute *attr,
-			    const char *buf, size_t count);
-static DEVICE_ATTR_RW(textid);
-
-static ssize_t remaining_steps_show(struct device *dev,
-				    struct device_attribute *attr, char *buf);
-static ssize_t remaining_steps_store(struct device *dev,
-				     struct device_attribute *attr,
-				     const char *buf, size_t count);
-static DEVICE_ATTR_RW(remaining_steps);
-
-static ssize_t devicedisabled_store(struct device *dev,
-				    struct device_attribute *attr,
-				    const char *buf, size_t count);
-static DEVICE_ATTR_WO(devicedisabled);
-
-static ssize_t deviceenabled_store(struct device *dev,
-				   struct device_attribute *attr,
-				   const char *buf, size_t count);
-static DEVICE_ATTR_WO(deviceenabled);
-
-static struct attribute *visorchipset_install_attrs[] = {
-	&dev_attr_toolaction.attr,
-	&dev_attr_boottotool.attr,
-	&dev_attr_error.attr,
-	&dev_attr_textid.attr,
-	&dev_attr_remaining_steps.attr,
-	NULL
-};
-
-static struct attribute_group visorchipset_install_group = {
-	.name = "install",
-	.attrs = visorchipset_install_attrs
-};
-
-static struct attribute *visorchipset_parahotplug_attrs[] = {
-	&dev_attr_devicedisabled.attr,
-	&dev_attr_deviceenabled.attr,
-	NULL
-};
-
-static struct attribute_group visorchipset_parahotplug_group = {
-	.name = "parahotplug",
-	.attrs = visorchipset_parahotplug_attrs
-};
-
-static const struct attribute_group *visorchipset_dev_groups[] = {
-	&visorchipset_install_group,
-	&visorchipset_parahotplug_group,
-	NULL
-};
-
-static void visorchipset_dev_release(struct device *dev)
-{
-}
-
-/* /sys/devices/platform/visorchipset */
-static struct platform_device visorchipset_platform_device = {
-	.name = "visorchipset",
-	.id = -1,
-	.dev.groups = visorchipset_dev_groups,
-	.dev.release = visorchipset_dev_release,
-};
-
-/* Function prototypes */
-static void controlvm_respond(struct controlvm_message_header *msg_hdr,
-			      int response);
-static void controlvm_respond_chipset_init(
-		struct controlvm_message_header *msg_hdr, int response,
-		enum ultra_chipset_feature features);
-static void controlvm_respond_physdev_changestate(
-		struct controlvm_message_header *msg_hdr, int response,
-		struct spar_segment_state state);
-
-static void parser_done(struct parser_context *ctx);
-
-static struct parser_context *
-parser_init_byte_stream(u64 addr, u32 bytes, bool local, bool *retry)
-{
-	int allocbytes = sizeof(struct parser_context) + bytes;
-	struct parser_context *ctx;
-
-	if (retry)
-		*retry = false;
-
-	/*
-	 * alloc an 0 extra byte to ensure payload is
-	 * '\0'-terminated
-	 */
-	allocbytes++;
-	if ((controlvm_payload_bytes_buffered + bytes)
-	    > MAX_CONTROLVM_PAYLOAD_BYTES) {
-		if (retry)
-			*retry = true;
-		return NULL;
-	}
-	ctx = kzalloc(allocbytes, GFP_KERNEL | __GFP_NORETRY);
-	if (!ctx) {
-		if (retry)
-			*retry = true;
-		return NULL;
-	}
-
-	ctx->allocbytes = allocbytes;
-	ctx->param_bytes = bytes;
-	ctx->curr = NULL;
-	ctx->bytes_remaining = 0;
-	ctx->byte_stream = false;
-	if (local) {
-		void *p;
-
-		if (addr > virt_to_phys(high_memory - 1))
-			goto err_finish_ctx;
-		p = __va((unsigned long)(addr));
-		memcpy(ctx->data, p, bytes);
-	} else {
-		void *mapping = memremap(addr, bytes, MEMREMAP_WB);
-
-		if (!mapping)
-			goto err_finish_ctx;
-		memcpy(ctx->data, mapping, bytes);
-		memunmap(mapping);
-	}
-
-	ctx->byte_stream = true;
-	controlvm_payload_bytes_buffered += ctx->param_bytes;
-
-	return ctx;
-
-err_finish_ctx:
-	parser_done(ctx);
-	return NULL;
-}
-
-static uuid_le
-parser_id_get(struct parser_context *ctx)
-{
-	struct spar_controlvm_parameters_header *phdr = NULL;
-
-	if (!ctx)
-		return NULL_UUID_LE;
-	phdr = (struct spar_controlvm_parameters_header *)(ctx->data);
-	return phdr->id;
-}
-
-/** Describes the state from the perspective of which controlvm messages have
- *  been received for a bus or device.
- */
-
-enum PARSER_WHICH_STRING {
-	PARSERSTRING_INITIATOR,
-	PARSERSTRING_TARGET,
-	PARSERSTRING_CONNECTION,
-	PARSERSTRING_NAME, /* TODO: only PARSERSTRING_NAME is used ? */
-};
-
-static void
-parser_param_start(struct parser_context *ctx,
-		   enum PARSER_WHICH_STRING which_string)
-{
-	struct spar_controlvm_parameters_header *phdr = NULL;
-
-	if (!ctx)
-		return;
-
-	phdr = (struct spar_controlvm_parameters_header *)(ctx->data);
-	switch (which_string) {
-	case PARSERSTRING_INITIATOR:
-		ctx->curr = ctx->data + phdr->initiator_offset;
-		ctx->bytes_remaining = phdr->initiator_length;
-		break;
-	case PARSERSTRING_TARGET:
-		ctx->curr = ctx->data + phdr->target_offset;
-		ctx->bytes_remaining = phdr->target_length;
-		break;
-	case PARSERSTRING_CONNECTION:
-		ctx->curr = ctx->data + phdr->connection_offset;
-		ctx->bytes_remaining = phdr->connection_length;
-		break;
-	case PARSERSTRING_NAME:
-		ctx->curr = ctx->data + phdr->name_offset;
-		ctx->bytes_remaining = phdr->name_length;
-		break;
-	default:
-		break;
-	}
-}
-
-static void parser_done(struct parser_context *ctx)
-{
-	if (!ctx)
-		return;
-	controlvm_payload_bytes_buffered -= ctx->param_bytes;
-	kfree(ctx);
-}
-
-static void *
-parser_string_get(struct parser_context *ctx)
-{
-	u8 *pscan;
-	unsigned long nscan;
-	int value_length = -1;
-	void *value = NULL;
-	int i;
-
-	if (!ctx)
-		return NULL;
-	pscan = ctx->curr;
-	nscan = ctx->bytes_remaining;
-	if (nscan == 0)
-		return NULL;
-	if (!pscan)
-		return NULL;
-	for (i = 0, value_length = -1; i < nscan; i++)
-		if (pscan[i] == '\0') {
-			value_length = i;
-			break;
-		}
-	if (value_length < 0)	/* '\0' was not included in the length */
-		value_length = nscan;
-	value = kmalloc(value_length + 1, GFP_KERNEL | __GFP_NORETRY);
-	if (!value)
-		return NULL;
-	if (value_length > 0)
-		memcpy(value, pscan, value_length);
-	((u8 *)(value))[value_length] = '\0';
-	return value;
-}
-
-static ssize_t toolaction_show(struct device *dev,
 			       struct device_attribute *attr,
 			       char *buf)
 {
@@ -513,6 +212,7 @@ static ssize_t toolaction_store(struct device *dev,
 		return ret;
 	return count;
 }
+static DEVICE_ATTR_RW(toolaction);
 
 static ssize_t boottotool_show(struct device *dev,
 			       struct device_attribute *attr,
@@ -549,6 +249,7 @@ static ssize_t boottotool_store(struct device *dev,
 		return ret;
 	return count;
 }
+static DEVICE_ATTR_RW(boottotool);
 
 static ssize_t error_show(struct device *dev, struct device_attribute *attr,
 			  char *buf)
@@ -580,6 +281,7 @@ static ssize_t error_store(struct device *dev, struct device_attribute *attr,
 		return ret;
 	return count;
 }
+static DEVICE_ATTR_RW(error);
 
 static ssize_t textid_show(struct device *dev, struct device_attribute *attr,
 			   char *buf)
@@ -612,6 +314,7 @@ static ssize_t textid_store(struct device *dev, struct device_attribute *attr,
 		return ret;
 	return count;
 }
+static DEVICE_ATTR_RW(textid);
 
 static ssize_t remaining_steps_show(struct device *dev,
 				    struct device_attribute *attr, char *buf)
@@ -644,6 +347,103 @@ static ssize_t remaining_steps_store(struct device *dev,
 		return ret;
 	return count;
 }
+static DEVICE_ATTR_RW(remaining_steps);
+
+static uuid_le
+parser_id_get(struct parser_context *ctx)
+{
+	struct spar_controlvm_parameters_header *phdr = NULL;
+
+	if (!ctx)
+		return NULL_UUID_LE;
+	phdr = (struct spar_controlvm_parameters_header *)(ctx->data);
+	return phdr->id;
+}
+
+/*
+ * Describes the state from the perspective of which controlvm messages have
+ * been received for a bus or device.
+ */
+
+enum PARSER_WHICH_STRING {
+	PARSERSTRING_INITIATOR,
+	PARSERSTRING_TARGET,
+	PARSERSTRING_CONNECTION,
+	PARSERSTRING_NAME, /* TODO: only PARSERSTRING_NAME is used ? */
+};
+
+static void
+parser_param_start(struct parser_context *ctx,
+		   enum PARSER_WHICH_STRING which_string)
+{
+	struct spar_controlvm_parameters_header *phdr = NULL;
+
+	if (!ctx)
+		return;
+
+	phdr = (struct spar_controlvm_parameters_header *)(ctx->data);
+	switch (which_string) {
+	case PARSERSTRING_INITIATOR:
+		ctx->curr = ctx->data + phdr->initiator_offset;
+		ctx->bytes_remaining = phdr->initiator_length;
+		break;
+	case PARSERSTRING_TARGET:
+		ctx->curr = ctx->data + phdr->target_offset;
+		ctx->bytes_remaining = phdr->target_length;
+		break;
+	case PARSERSTRING_CONNECTION:
+		ctx->curr = ctx->data + phdr->connection_offset;
+		ctx->bytes_remaining = phdr->connection_length;
+		break;
+	case PARSERSTRING_NAME:
+		ctx->curr = ctx->data + phdr->name_offset;
+		ctx->bytes_remaining = phdr->name_length;
+		break;
+	default:
+		break;
+	}
+}
+
+static void parser_done(struct parser_context *ctx)
+{
+	if (!ctx)
+		return;
+	controlvm_payload_bytes_buffered -= ctx->param_bytes;
+	kfree(ctx);
+}
+
+static void *
+parser_string_get(struct parser_context *ctx)
+{
+	u8 *pscan;
+	unsigned long nscan;
+	int value_length = -1;
+	void *value = NULL;
+	int i;
+
+	if (!ctx)
+		return NULL;
+	pscan = ctx->curr;
+	nscan = ctx->bytes_remaining;
+	if (nscan == 0)
+		return NULL;
+	if (!pscan)
+		return NULL;
+	for (i = 0, value_length = -1; i < nscan; i++)
+		if (pscan[i] == '\0') {
+			value_length = i;
+			break;
+		}
+	if (value_length < 0)	/* '\0' was not included in the length */
+		value_length = nscan;
+	value = kmalloc(value_length + 1, GFP_KERNEL | __GFP_NORETRY);
+	if (!value)
+		return NULL;
+	if (value_length > 0)
+		memcpy(value, pscan, value_length);
+	((u8 *)(value))[value_length] = '\0';
+	return value;
+}
 
 struct visor_busdev {
 	u32 bus_no;
@@ -683,32 +483,36 @@ struct visor_device *visorbus_get_device_by_id(u32 bus_no, u32 dev_no,
 		vdev = to_visor_device(dev);
 	return vdev;
 }
-EXPORT_SYMBOL(visorbus_get_device_by_id);
 
-void
-visorchipset_register_busdev(
-			struct visorchipset_busdev_notifiers *notifiers,
-			struct visorchipset_busdev_responders *responders,
-			struct ultra_vbus_deviceinfo *driver_info)
-{
-	down(&notifier_lock);
-	if (!notifiers) {
-		memset(&busdev_notifiers, 0,
-		       sizeof(busdev_notifiers));
-		visorbusregistered = 0;	/* clear flag */
-	} else {
-		busdev_notifiers = *notifiers;
-		visorbusregistered = 1;	/* set flag */
+static void
+controlvm_init_response(struct controlvm_message *msg,
+			struct controlvm_message_header *msg_hdr, int response)
+{
+	memset(msg, 0, sizeof(struct controlvm_message));
+	memcpy(&msg->hdr, msg_hdr, sizeof(struct controlvm_message_header));
+	msg->hdr.payload_bytes = 0;
+	msg->hdr.payload_vm_offset = 0;
+	msg->hdr.payload_max_bytes = 0;
+	if (response < 0) {
+		msg->hdr.flags.failed = 1;
+		msg->hdr.completion_status = (u32)(-response);
 	}
-	if (responders)
-		*responders = busdev_responders;
-	if (driver_info)
-		bus_device_info_init(driver_info, "chipset", "visorchipset",
-				     VERSION, NULL);
+}
+
+static void
+controlvm_respond_chipset_init(struct controlvm_message_header *msg_hdr,
+			       int response,
+			       enum ultra_chipset_feature features)
+{
+	struct controlvm_message outmsg;
 
-	up(&notifier_lock);
+	controlvm_init_response(&outmsg, msg_hdr, response);
+	outmsg.cmd.init_chipset.features = features;
+	if (visorchannel_signalinsert(controlvm_channel,
+				      CONTROLVM_QUEUE_REQUEST, &outmsg)) {
+		return;
+	}
 }
-EXPORT_SYMBOL_GPL(visorchipset_register_busdev);
 
 static void
 chipset_init(struct controlvm_message *inmsg)
@@ -725,14 +529,16 @@ chipset_init(struct controlvm_message *inmsg)
 	chipset_inited = 1;
 	POSTCODE_LINUX_2(CHIPSET_INIT_EXIT_PC, POSTCODE_SEVERITY_INFO);
 
-	/* Set features to indicate we support parahotplug (if Command
+	/*
+	 * Set features to indicate we support parahotplug (if Command
 	 * also supports it).
 	 */
 	features =
 	    inmsg->cmd.init_chipset.
 	    features & ULTRA_CHIPSET_FEATURE_PARA_HOTPLUG;
 
-	/* Set the "reply" bit so Command knows this is a
+	/*
+	 * Set the "reply" bit so Command knows this is a
 	 * features-aware driver.
 	 */
 	features |= ULTRA_CHIPSET_FEATURE_REPLY;
@@ -743,21 +549,6 @@ out_respond:
 }
 
 static void
-controlvm_init_response(struct controlvm_message *msg,
-			struct controlvm_message_header *msg_hdr, int response)
-{
-	memset(msg, 0, sizeof(struct controlvm_message));
-	memcpy(&msg->hdr, msg_hdr, sizeof(struct controlvm_message_header));
-	msg->hdr.payload_bytes = 0;
-	msg->hdr.payload_vm_offset = 0;
-	msg->hdr.payload_max_bytes = 0;
-	if (response < 0) {
-		msg->hdr.flags.failed = 1;
-		msg->hdr.completion_status = (u32)(-response);
-	}
-}
-
-static void
 controlvm_respond(struct controlvm_message_header *msg_hdr, int response)
 {
 	struct controlvm_message outmsg;
@@ -766,23 +557,8 @@ controlvm_respond(struct controlvm_message_header *msg_hdr, int response)
 	if (outmsg.hdr.flags.test_message == 1)
 		return;
 
-	if (!visorchannel_signalinsert(controlvm_channel,
-				       CONTROLVM_QUEUE_REQUEST, &outmsg)) {
-		return;
-	}
-}
-
-static void
-controlvm_respond_chipset_init(struct controlvm_message_header *msg_hdr,
-			       int response,
-			       enum ultra_chipset_feature features)
-{
-	struct controlvm_message outmsg;
-
-	controlvm_init_response(&outmsg, msg_hdr, response);
-	outmsg.cmd.init_chipset.features = features;
-	if (!visorchannel_signalinsert(controlvm_channel,
-				       CONTROLVM_QUEUE_REQUEST, &outmsg)) {
+	if (visorchannel_signalinsert(controlvm_channel,
+				      CONTROLVM_QUEUE_REQUEST, &outmsg)) {
 		return;
 	}
 }
@@ -796,8 +572,8 @@ static void controlvm_respond_physdev_changestate(
 	controlvm_init_response(&outmsg, msg_hdr, response);
 	outmsg.cmd.device_change_state.state = state;
 	outmsg.cmd.device_change_state.flags.phys_device = 1;
-	if (!visorchannel_signalinsert(controlvm_channel,
-				       CONTROLVM_QUEUE_REQUEST, &outmsg)) {
+	if (visorchannel_signalinsert(controlvm_channel,
+				      CONTROLVM_QUEUE_REQUEST, &outmsg)) {
 		return;
 	}
 }
@@ -894,8 +670,8 @@ device_changestate_responder(enum controlvm_id cmd_id,
 	outmsg.cmd.device_change_state.dev_no = dev_no;
 	outmsg.cmd.device_change_state.state = response_state;
 
-	if (!visorchannel_signalinsert(controlvm_channel,
-				       CONTROLVM_QUEUE_REQUEST, &outmsg))
+	if (visorchannel_signalinsert(controlvm_channel,
+				      CONTROLVM_QUEUE_REQUEST, &outmsg))
 		return;
 }
 
@@ -920,20 +696,20 @@ bus_epilog(struct visor_device *bus_info,
 {
 	struct controlvm_message_header *pmsg_hdr = NULL;
 
-	down(&notifier_lock);
-
 	if (!bus_info) {
-		/* relying on a valid passed in response code */
-		/* be lazy and re-use msg_hdr for this failure, is this ok?? */
+		/*
+		 * relying on a valid passed in response code
+		 * be lazy and re-use msg_hdr for this failure, is this ok??
+		 */
 		pmsg_hdr = msg_hdr;
-		goto out_respond_and_unlock;
+		goto out_respond;
 	}
 
 	if (bus_info->pending_msg_hdr) {
 		/* only non-NULL if dev is still waiting on a response */
 		response = -CONTROLVM_RESP_ERROR_MESSAGE_ID_INVALID_FOR_CLIENT;
 		pmsg_hdr = bus_info->pending_msg_hdr;
-		goto out_respond_and_unlock;
+		goto out_respond;
 	}
 
 	if (need_response) {
@@ -942,7 +718,7 @@ bus_epilog(struct visor_device *bus_info,
 			POSTCODE_LINUX_4(MALLOC_FAILURE_PC, cmd,
 					 bus_info->chipset_bus_no,
 					 POSTCODE_SEVERITY_ERR);
-			goto out_unlock;
+			return;
 		}
 
 		memcpy(pmsg_hdr, msg_hdr,
@@ -953,25 +729,16 @@ bus_epilog(struct visor_device *bus_info,
 	if (response == CONTROLVM_RESP_SUCCESS) {
 		switch (cmd) {
 		case CONTROLVM_BUS_CREATE:
-			if (busdev_notifiers.bus_create) {
-				(*busdev_notifiers.bus_create) (bus_info);
-				goto out_unlock;
-			}
+			chipset_bus_create(bus_info);
 			break;
 		case CONTROLVM_BUS_DESTROY:
-			if (busdev_notifiers.bus_destroy) {
-				(*busdev_notifiers.bus_destroy) (bus_info);
-				goto out_unlock;
-			}
+			chipset_bus_destroy(bus_info);
 			break;
 		}
 	}
 
-out_respond_and_unlock:
+out_respond:
 	bus_responder(cmd, pmsg_hdr, response);
-
-out_unlock:
-	up(&notifier_lock);
 }
 
 static void
@@ -980,31 +747,29 @@ device_epilog(struct visor_device *dev_info,
 	      struct controlvm_message_header *msg_hdr, int response,
 	      bool need_response, bool for_visorbus)
 {
-	struct visorchipset_busdev_notifiers *notifiers;
 	struct controlvm_message_header *pmsg_hdr = NULL;
 
-	notifiers = &busdev_notifiers;
-
-	down(&notifier_lock);
 	if (!dev_info) {
-		/* relying on a valid passed in response code */
-		/* be lazy and re-use msg_hdr for this failure, is this ok?? */
+		/*
+		 * relying on a valid passed in response code
+		 * be lazy and re-use msg_hdr for this failure, is this ok??
+		 */
 		pmsg_hdr = msg_hdr;
-		goto out_respond_and_unlock;
+		goto out_respond;
 	}
 
 	if (dev_info->pending_msg_hdr) {
 		/* only non-NULL if dev is still waiting on a response */
 		response = -CONTROLVM_RESP_ERROR_MESSAGE_ID_INVALID_FOR_CLIENT;
 		pmsg_hdr = dev_info->pending_msg_hdr;
-		goto out_respond_and_unlock;
+		goto out_respond;
 	}
 
 	if (need_response) {
 		pmsg_hdr = kzalloc(sizeof(*pmsg_hdr), GFP_KERNEL);
 		if (!pmsg_hdr) {
 			response = -CONTROLVM_RESP_ERROR_KMALLOC_FAILED;
-			goto out_respond_and_unlock;
+			goto out_respond;
 		}
 
 		memcpy(pmsg_hdr, msg_hdr,
@@ -1015,48 +780,34 @@ device_epilog(struct visor_device *dev_info,
 	if (response >= 0) {
 		switch (cmd) {
 		case CONTROLVM_DEVICE_CREATE:
-			if (notifiers->device_create) {
-				(*notifiers->device_create) (dev_info);
-				goto out_unlock;
-			}
+			chipset_device_create(dev_info);
 			break;
 		case CONTROLVM_DEVICE_CHANGESTATE:
 			/* ServerReady / ServerRunning / SegmentStateRunning */
 			if (state.alive == segment_state_running.alive &&
 			    state.operating ==
 				segment_state_running.operating) {
-				if (notifiers->device_resume) {
-					(*notifiers->device_resume) (dev_info);
-					goto out_unlock;
-				}
+				chipset_device_resume(dev_info);
 			}
 			/* ServerNotReady / ServerLost / SegmentStateStandby */
 			else if (state.alive == segment_state_standby.alive &&
 				 state.operating ==
 				 segment_state_standby.operating) {
-				/* technically this is standby case
+				/*
+				 * technically this is standby case
 				 * where server is lost
 				 */
-				if (notifiers->device_pause) {
-					(*notifiers->device_pause) (dev_info);
-					goto out_unlock;
-				}
+				chipset_device_pause(dev_info);
 			}
 			break;
 		case CONTROLVM_DEVICE_DESTROY:
-			if (notifiers->device_destroy) {
-				(*notifiers->device_destroy) (dev_info);
-				goto out_unlock;
-			}
+			chipset_device_destroy(dev_info);
 			break;
 		}
 	}
 
-out_respond_and_unlock:
+out_respond:
 	device_responder(cmd, pmsg_hdr, response);
-
-out_unlock:
-	up(&notifier_lock);
 }
 
 static void
@@ -1103,10 +854,8 @@ bus_create(struct controlvm_message *inmsg)
 		goto out_bus_epilog;
 	}
 	bus_info->visorchannel = visorchannel;
-	if (uuid_le_cmp(cmd->create_bus.bus_inst_uuid, spar_siovm_uuid) == 0) {
-		dump_vhba_bus = bus_no;
+	if (uuid_le_cmp(cmd->create_bus.bus_inst_uuid, spar_siovm_uuid) == 0)
 		save_crash_message(inmsg, CRASH_BUS);
-	}
 
 	POSTCODE_LINUX_3(BUS_CREATE_EXIT_PC, bus_no, POSTCODE_SEVERITY_INFO);
 
@@ -1303,11 +1052,19 @@ my_device_destroy(struct controlvm_message *inmsg)
 			      inmsg->hdr.flags.response_expected == 1, 1);
 }
 
-/* When provided with the physical address of the controlvm channel
+/**
+ * initialize_controlvm_payload_info() - init controlvm_payload_info struct
+ * @phys_addr: the physical address of controlvm channel
+ * @offset:    the offset to payload
+ * @bytes:     the size of the payload in bytes
+ * @info:      the returning valid struct
+ *
+ * When provided with the physical address of the controlvm channel
  * (phys_addr), the offset to the payload area we need to manage
  * (offset), and the size of this payload area (bytes), fills in the
- * controlvm_payload_info struct.  Returns true for success or false
- * for failure.
+ * controlvm_payload_info struct.
+ *
+ * Return: CONTROLVM_RESP_SUCCESS for success or a negative for failure
  */
 static int
 initialize_controlvm_payload_info(u64 phys_addr, u64 offset, u32 bytes,
@@ -1371,95 +1128,14 @@ initialize_controlvm_payload(void)
 					  &controlvm_payload_info);
 }
 
-/*  Send ACTION=online for DEVPATH=/sys/devices/platform/visorchipset.
- *  Returns CONTROLVM_RESP_xxx code.
- */
-static int
-visorchipset_chipset_ready(void)
-{
-	kobject_uevent(&visorchipset_platform_device.dev.kobj, KOBJ_ONLINE);
-	return CONTROLVM_RESP_SUCCESS;
-}
-
-static int
-visorchipset_chipset_selftest(void)
-{
-	char env_selftest[20];
-	char *envp[] = { env_selftest, NULL };
-
-	sprintf(env_selftest, "SPARSP_SELFTEST=%d", 1);
-	kobject_uevent_env(&visorchipset_platform_device.dev.kobj, KOBJ_CHANGE,
-			   envp);
-	return CONTROLVM_RESP_SUCCESS;
-}
-
-/*  Send ACTION=offline for DEVPATH=/sys/devices/platform/visorchipset.
- *  Returns CONTROLVM_RESP_xxx code.
- */
-static int
-visorchipset_chipset_notready(void)
-{
-	kobject_uevent(&visorchipset_platform_device.dev.kobj, KOBJ_OFFLINE);
-	return CONTROLVM_RESP_SUCCESS;
-}
-
-static void
-chipset_ready(struct controlvm_message_header *msg_hdr)
-{
-	int rc = visorchipset_chipset_ready();
-
-	if (rc != CONTROLVM_RESP_SUCCESS)
-		rc = -rc;
-	if (msg_hdr->flags.response_expected)
-		controlvm_respond(msg_hdr, rc);
-}
-
-static void
-chipset_selftest(struct controlvm_message_header *msg_hdr)
-{
-	int rc = visorchipset_chipset_selftest();
-
-	if (rc != CONTROLVM_RESP_SUCCESS)
-		rc = -rc;
-	if (msg_hdr->flags.response_expected)
-		controlvm_respond(msg_hdr, rc);
-}
-
-static void
-chipset_notready(struct controlvm_message_header *msg_hdr)
-{
-	int rc = visorchipset_chipset_notready();
-
-	if (rc != CONTROLVM_RESP_SUCCESS)
-		rc = -rc;
-	if (msg_hdr->flags.response_expected)
-		controlvm_respond(msg_hdr, rc);
-}
-
-/* This is your "one-stop" shop for grabbing the next message from the
- * CONTROLVM_QUEUE_EVENT queue in the controlvm channel.
- */
-static bool
-read_controlvm_event(struct controlvm_message *msg)
-{
-	if (visorchannel_signalremove(controlvm_channel,
-				      CONTROLVM_QUEUE_EVENT, msg)) {
-		/* got a message */
-		if (msg->hdr.flags.test_message == 1)
-			return false;
-		return true;
-	}
-	return false;
-}
-
 /*
- * The general parahotplug flow works as follows.  The visorchipset
+ * The general parahotplug flow works as follows. The visorchipset
  * driver receives a DEVICE_CHANGESTATE message from Command
- * specifying a physical device to enable or disable.  The CONTROLVM
+ * specifying a physical device to enable or disable. The CONTROLVM
  * message handler calls parahotplug_process_message, which then adds
  * the message to a global list and kicks off a udev event which
  * causes a user level script to enable or disable the specified
- * device.  The udev script then writes to
+ * device. The udev script then writes to
  * /proc/visorchipset/parahotplug, which causes parahotplug_proc_write
  * to get called, at which point the appropriate CONTROLVM message is
  * retrieved from the list and responded to.
@@ -1467,9 +1143,11 @@ read_controlvm_event(struct controlvm_message *msg)
 
 #define PARAHOTPLUG_TIMEOUT_MS 2000
 
-/*
- * Generate unique int to match an outstanding CONTROLVM message with a
- * udev script /proc response
+/**
+ * parahotplug_next_id() - generate unique int to match an outstanding CONTROLVM
+ *                         message with a udev script /proc response
+ *
+ * Return: a unique integer value
  */
 static int
 parahotplug_next_id(void)
@@ -1479,9 +1157,12 @@ parahotplug_next_id(void)
 	return atomic_inc_return(&id);
 }
 
-/*
- * Returns the time (in jiffies) when a CONTROLVM message on the list
- * should expire -- PARAHOTPLUG_TIMEOUT_MS in the future
+/**
+ * parahotplug_next_expiration() - returns the time (in jiffies) when a
+ *                                 CONTROLVM message on the list should expire
+ *                                 -- PARAHOTPLUG_TIMEOUT_MS in the future
+ *
+ * Return: expected expiration time (in jiffies)
  */
 static unsigned long
 parahotplug_next_expiration(void)
@@ -1489,9 +1170,13 @@ parahotplug_next_expiration(void)
 	return jiffies + msecs_to_jiffies(PARAHOTPLUG_TIMEOUT_MS);
 }
 
-/*
- * Create a parahotplug_request, which is basically a wrapper for a
- * CONTROLVM_MESSAGE that we can stick on a list
+/**
+ * parahotplug_request_create() - create a parahotplug_request, which is
+ *                                basically a wrapper for a CONTROLVM_MESSAGE
+ *                                that we can stick on a list
+ * @msg: the message to insert in the request
+ *
+ * Return: the request containing the provided message
  */
 static struct parahotplug_request *
 parahotplug_request_create(struct controlvm_message *msg)
@@ -1509,8 +1194,9 @@ parahotplug_request_create(struct controlvm_message *msg)
 	return req;
 }
 
-/*
- * Free a parahotplug_request.
+/**
+ * parahotplug_request_destroy() - free a parahotplug_request
+ * @req: the request to deallocate
  */
 static void
 parahotplug_request_destroy(struct parahotplug_request *req)
@@ -1518,71 +1204,19 @@ parahotplug_request_destroy(struct parahotplug_request *req)
 	kfree(req);
 }
 
-/*
- * Cause uevent to run the user level script to do the disable/enable
- * specified in (the CONTROLVM message in) the specified
- * parahotplug_request
- */
-static void
-parahotplug_request_kickoff(struct parahotplug_request *req)
-{
-	struct controlvm_message_packet *cmd = &req->msg.cmd;
-	char env_cmd[40], env_id[40], env_state[40], env_bus[40], env_dev[40],
-	    env_func[40];
-	char *envp[] = {
-		env_cmd, env_id, env_state, env_bus, env_dev, env_func, NULL
-	};
-
-	sprintf(env_cmd, "SPAR_PARAHOTPLUG=1");
-	sprintf(env_id, "SPAR_PARAHOTPLUG_ID=%d", req->id);
-	sprintf(env_state, "SPAR_PARAHOTPLUG_STATE=%d",
-		cmd->device_change_state.state.active);
-	sprintf(env_bus, "SPAR_PARAHOTPLUG_BUS=%d",
-		cmd->device_change_state.bus_no);
-	sprintf(env_dev, "SPAR_PARAHOTPLUG_DEVICE=%d",
-		cmd->device_change_state.dev_no >> 3);
-	sprintf(env_func, "SPAR_PARAHOTPLUG_FUNCTION=%d",
-		cmd->device_change_state.dev_no & 0x7);
-
-	kobject_uevent_env(&visorchipset_platform_device.dev.kobj, KOBJ_CHANGE,
-			   envp);
-}
-
-/*
- * Remove any request from the list that's been on there too long and
- * respond with an error.
- */
-static void
-parahotplug_process_list(void)
-{
-	struct list_head *pos;
-	struct list_head *tmp;
-
-	spin_lock(&parahotplug_request_list_lock);
-
-	list_for_each_safe(pos, tmp, &parahotplug_request_list) {
-		struct parahotplug_request *req =
-		    list_entry(pos, struct parahotplug_request, list);
-
-		if (!time_after_eq(jiffies, req->expiration))
-			continue;
-
-		list_del(pos);
-		if (req->msg.hdr.flags.response_expected)
-			controlvm_respond_physdev_changestate(
-				&req->msg.hdr,
-				CONTROLVM_RESP_ERROR_DEVICE_UDEV_TIMEOUT,
-				req->msg.cmd.device_change_state.state);
-		parahotplug_request_destroy(req);
-	}
-
-	spin_unlock(&parahotplug_request_list_lock);
-}
+static LIST_HEAD(parahotplug_request_list);
+static DEFINE_SPINLOCK(parahotplug_request_list_lock);	/* lock for above */
 
-/*
+/**
+ * parahotplug_request_complete() - mark request as complete
+ * @id:     the id of the request
+ * @active: indicates whether the request is assigned to active partition
+ *
  * Called from the /proc handler, which means the user script has
- * finished the enable/disable.  Find the matching identifier, and
+ * finished the enable/disable. Find the matching identifier, and
  * respond to the CONTROLVM message with success.
+ *
+ * Return: 0 on success or -EINVAL on failure
  */
 static int
 parahotplug_request_complete(int id, u16 active)
@@ -1597,7 +1231,8 @@ parahotplug_request_complete(int id, u16 active)
 		struct parahotplug_request *req =
 		    list_entry(pos, struct parahotplug_request, list);
 		if (req->id == id) {
-			/* Found a match.  Remove it from the list and
+			/*
+			 * Found a match. Remove it from the list and
 			 * respond.
 			 */
 			list_del(pos);
@@ -1616,8 +1251,142 @@ parahotplug_request_complete(int id, u16 active)
 	return -EINVAL;
 }
 
-/*
- * Enables or disables a PCI device by kicking off a udev script
+/**
+ * devicedisabled_store() - disables the hotplug device
+ * @dev:   sysfs interface variable not utilized in this function
+ * @attr:  sysfs interface variable not utilized in this function
+ * @buf:   buffer containing the device id
+ * @count: the size of the buffer
+ *
+ * The parahotplug/devicedisabled interface gets called by our support script
+ * when an SR-IOV device has been shut down. The ID is passed to the script
+ * and then passed back when the device has been removed.
+ *
+ * Return: the size of the buffer for success or negative for error
+ */
+static ssize_t devicedisabled_store(struct device *dev,
+				    struct device_attribute *attr,
+				    const char *buf, size_t count)
+{
+	unsigned int id;
+	int err;
+
+	if (kstrtouint(buf, 10, &id))
+		return -EINVAL;
+
+	err = parahotplug_request_complete(id, 0);
+	if (err < 0)
+		return err;
+	return count;
+}
+static DEVICE_ATTR_WO(devicedisabled);
+
+/**
+ * deviceenabled_store() - enables the hotplug device
+ * @dev:   sysfs interface variable not utilized in this function
+ * @attr:  sysfs interface variable not utilized in this function
+ * @buf:   buffer containing the device id
+ * @count: the size of the buffer
+ *
+ * The parahotplug/deviceenabled interface gets called by our support script
+ * when an SR-IOV device has been recovered. The ID is passed to the script
+ * and then passed back when the device has been brought back up.
+ *
+ * Return: the size of the buffer for success or negative for error
+ */
+static ssize_t deviceenabled_store(struct device *dev,
+				   struct device_attribute *attr,
+				   const char *buf, size_t count)
+{
+	unsigned int id;
+
+	if (kstrtouint(buf, 10, &id))
+		return -EINVAL;
+
+	parahotplug_request_complete(id, 1);
+	return count;
+}
+static DEVICE_ATTR_WO(deviceenabled);
+
+static struct attribute *visorchipset_install_attrs[] = {
+	&dev_attr_toolaction.attr,
+	&dev_attr_boottotool.attr,
+	&dev_attr_error.attr,
+	&dev_attr_textid.attr,
+	&dev_attr_remaining_steps.attr,
+	NULL
+};
+
+static struct attribute_group visorchipset_install_group = {
+	.name = "install",
+	.attrs = visorchipset_install_attrs
+};
+
+static struct attribute *visorchipset_parahotplug_attrs[] = {
+	&dev_attr_devicedisabled.attr,
+	&dev_attr_deviceenabled.attr,
+	NULL
+};
+
+static struct attribute_group visorchipset_parahotplug_group = {
+	.name = "parahotplug",
+	.attrs = visorchipset_parahotplug_attrs
+};
+
+static const struct attribute_group *visorchipset_dev_groups[] = {
+	&visorchipset_install_group,
+	&visorchipset_parahotplug_group,
+	NULL
+};
+
+static void visorchipset_dev_release(struct device *dev)
+{
+}
+
+/* /sys/devices/platform/visorchipset */
+static struct platform_device visorchipset_platform_device = {
+	.name = "visorchipset",
+	.id = -1,
+	.dev.groups = visorchipset_dev_groups,
+	.dev.release = visorchipset_dev_release,
+};
+
+/**
+ * parahotplug_request_kickoff() - initiate parahotplug request
+ * @req: the request to initiate
+ *
+ * Cause uevent to run the user level script to do the disable/enable specified
+ * in the parahotplug_request.
+ */
+static void
+parahotplug_request_kickoff(struct parahotplug_request *req)
+{
+	struct controlvm_message_packet *cmd = &req->msg.cmd;
+	char env_cmd[40], env_id[40], env_state[40], env_bus[40], env_dev[40],
+	    env_func[40];
+	char *envp[] = {
+		env_cmd, env_id, env_state, env_bus, env_dev, env_func, NULL
+	};
+
+	sprintf(env_cmd, "SPAR_PARAHOTPLUG=1");
+	sprintf(env_id, "SPAR_PARAHOTPLUG_ID=%d", req->id);
+	sprintf(env_state, "SPAR_PARAHOTPLUG_STATE=%d",
+		cmd->device_change_state.state.active);
+	sprintf(env_bus, "SPAR_PARAHOTPLUG_BUS=%d",
+		cmd->device_change_state.bus_no);
+	sprintf(env_dev, "SPAR_PARAHOTPLUG_DEVICE=%d",
+		cmd->device_change_state.dev_no >> 3);
+	sprintf(env_func, "SPAR_PARAHOTPLUG_FUNCTION=%d",
+		cmd->device_change_state.dev_no & 0x7);
+
+	kobject_uevent_env(&visorchipset_platform_device.dev.kobj, KOBJ_CHANGE,
+			   envp);
+}
+
+/**
+ * parahotplug_process_message() - enables or disables a PCI device by kicking
+ *                                 off a udev script
+ * @inmsg: the message indicating whether to enable or disable
  */
 static void
 parahotplug_process_message(struct controlvm_message *inmsg)
@@ -1630,14 +1399,16 @@ parahotplug_process_message(struct controlvm_message *inmsg)
 		return;
 
 	if (inmsg->cmd.device_change_state.state.active) {
-		/* For enable messages, just respond with success
-		* right away.  This is a bit of a hack, but there are
-		* issues with the early enable messages we get (with
-		* either the udev script not detecting that the device
-		* is up, or not getting called at all).  Fortunately
-		* the messages that get lost don't matter anyway, as
-		* devices are automatically enabled at
-		* initialization.
+		/*
+		 * For enable messages, just respond with success
+		 * right away. This is a bit of a hack, but there are
+		 * issues with the early enable messages we get (with
+		 * either the udev script not detecting that the device
+		 * is up, or not getting called at all). Fortunately
+		 * the messages that get lost don't matter anyway, as
+		 *
+		 * devices are automatically enabled at
+		 * initialization.
 		*/
 		parahotplug_request_kickoff(req);
 		controlvm_respond_physdev_changestate
@@ -1646,11 +1417,12 @@ parahotplug_process_message(struct controlvm_message *inmsg)
 			 inmsg->cmd.device_change_state.state);
 		parahotplug_request_destroy(req);
 	} else {
-		/* For disable messages, add the request to the
-		* request list before kicking off the udev script.  It
-		* won't get responded to until the script has
-		* indicated it's done.
-		*/
+		/*
+		 * For disable messages, add the request to the
+		 * request list before kicking off the udev script. It
+		 * won't get responded to until the script has
+		 * indicated it's done.
+		 */
 		spin_lock(&parahotplug_request_list_lock);
 		list_add_tail(&req->list, &parahotplug_request_list);
 		spin_unlock(&parahotplug_request_list_lock);
@@ -1659,113 +1431,77 @@ parahotplug_process_message(struct controlvm_message *inmsg)
 	}
 }
 
-/* Process a controlvm message.
- * Return result:
- *    false - this function will return false only in the case where the
- *            controlvm message was NOT processed, but processing must be
- *            retried before reading the next controlvm message; a
- *            scenario where this can occur is when we need to throttle
- *            the allocation of memory in which to copy out controlvm
- *            payload data
- *    true  - processing of the controlvm message completed,
- *            either successfully or with an error.
+/**
+ * visorchipset_chipset_ready() - sends chipset_ready action
+ *
+ * Send ACTION=online for DEVPATH=/sys/devices/platform/visorchipset.
+ *
+ * Return: CONTROLVM_RESP_SUCCESS
  */
-static bool
-handle_command(struct controlvm_message inmsg, u64 channel_addr)
+static int
+visorchipset_chipset_ready(void)
 {
-	struct controlvm_message_packet *cmd = &inmsg.cmd;
-	u64 parm_addr;
-	u32 parm_bytes;
-	struct parser_context *parser_ctx = NULL;
-	bool local_addr;
-	struct controlvm_message ackmsg;
+	kobject_uevent(&visorchipset_platform_device.dev.kobj, KOBJ_ONLINE);
+	return CONTROLVM_RESP_SUCCESS;
+}
 
-	/* create parsing context if necessary */
-	local_addr = (inmsg.hdr.flags.test_message == 1);
-	if (channel_addr == 0)
-		return true;
-	parm_addr = channel_addr + inmsg.hdr.payload_vm_offset;
-	parm_bytes = inmsg.hdr.payload_bytes;
+static int
+visorchipset_chipset_selftest(void)
+{
+	char env_selftest[20];
+	char *envp[] = { env_selftest, NULL };
 
-	/* Parameter and channel addresses within test messages actually lie
-	 * within our OS-controlled memory.  We need to know that, because it
-	 * makes a difference in how we compute the virtual address.
-	 */
-	if (parm_addr && parm_bytes) {
-		bool retry = false;
+	sprintf(env_selftest, "SPARSP_SELFTEST=%d", 1);
+	kobject_uevent_env(&visorchipset_platform_device.dev.kobj, KOBJ_CHANGE,
+			   envp);
+	return CONTROLVM_RESP_SUCCESS;
+}
 
-		parser_ctx =
-		    parser_init_byte_stream(parm_addr, parm_bytes,
-					    local_addr, &retry);
-		if (!parser_ctx && retry)
-			return false;
-	}
+/**
+ * visorchipset_chipset_notready() - sends chipset_notready action
+ *
+ * Send ACTION=offline for DEVPATH=/sys/devices/platform/visorchipset.
+ *
+ * Return: CONTROLVM_RESP_SUCCESS
+ */
+static int
+visorchipset_chipset_notready(void)
+{
+	kobject_uevent(&visorchipset_platform_device.dev.kobj, KOBJ_OFFLINE);
+	return CONTROLVM_RESP_SUCCESS;
+}
 
-	if (!local_addr) {
-		controlvm_init_response(&ackmsg, &inmsg.hdr,
-					CONTROLVM_RESP_SUCCESS);
-		if (controlvm_channel)
-			visorchannel_signalinsert(controlvm_channel,
-						  CONTROLVM_QUEUE_ACK,
-						  &ackmsg);
-	}
-	switch (inmsg.hdr.id) {
-	case CONTROLVM_CHIPSET_INIT:
-		chipset_init(&inmsg);
-		break;
-	case CONTROLVM_BUS_CREATE:
-		bus_create(&inmsg);
-		break;
-	case CONTROLVM_BUS_DESTROY:
-		bus_destroy(&inmsg);
-		break;
-	case CONTROLVM_BUS_CONFIGURE:
-		bus_configure(&inmsg, parser_ctx);
-		break;
-	case CONTROLVM_DEVICE_CREATE:
-		my_device_create(&inmsg);
-		break;
-	case CONTROLVM_DEVICE_CHANGESTATE:
-		if (cmd->device_change_state.flags.phys_device) {
-			parahotplug_process_message(&inmsg);
-		} else {
-			/* save the hdr and cmd structures for later use */
-			/* when sending back the response to Command */
-			my_device_changestate(&inmsg);
-			g_devicechangestate_packet = inmsg.cmd;
-			break;
-		}
-		break;
-	case CONTROLVM_DEVICE_DESTROY:
-		my_device_destroy(&inmsg);
-		break;
-	case CONTROLVM_DEVICE_CONFIGURE:
-		/* no op for now, just send a respond that we passed */
-		if (inmsg.hdr.flags.response_expected)
-			controlvm_respond(&inmsg.hdr, CONTROLVM_RESP_SUCCESS);
-		break;
-	case CONTROLVM_CHIPSET_READY:
-		chipset_ready(&inmsg.hdr);
-		break;
-	case CONTROLVM_CHIPSET_SELFTEST:
-		chipset_selftest(&inmsg.hdr);
-		break;
-	case CONTROLVM_CHIPSET_STOP:
-		chipset_notready(&inmsg.hdr);
-		break;
-	default:
-		if (inmsg.hdr.flags.response_expected)
-			controlvm_respond
-				(&inmsg.hdr,
-				 -CONTROLVM_RESP_ERROR_MESSAGE_ID_UNKNOWN);
-		break;
-	}
+static void
+chipset_ready(struct controlvm_message_header *msg_hdr)
+{
+	int rc = visorchipset_chipset_ready();
 
-	if (parser_ctx) {
-		parser_done(parser_ctx);
-		parser_ctx = NULL;
-	}
-	return true;
+	if (rc != CONTROLVM_RESP_SUCCESS)
+		rc = -rc;
+	if (msg_hdr->flags.response_expected)
+		controlvm_respond(msg_hdr, rc);
+}
+
+static void
+chipset_selftest(struct controlvm_message_header *msg_hdr)
+{
+	int rc = visorchipset_chipset_selftest();
+
+	if (rc != CONTROLVM_RESP_SUCCESS)
+		rc = -rc;
+	if (msg_hdr->flags.response_expected)
+		controlvm_respond(msg_hdr, rc);
+}
+
+static void
+chipset_notready(struct controlvm_message_header *msg_hdr)
+{
+	int rc = visorchipset_chipset_notready();
+
+	if (rc != CONTROLVM_RESP_SUCCESS)
+		rc = -rc;
+	if (msg_hdr->flags.response_expected)
+		controlvm_respond(msg_hdr, rc);
 }
 
 static inline unsigned int
@@ -1796,76 +1532,6 @@ static u64 controlvm_get_channel_address(void)
 }
 
 static void
-controlvm_periodic_work(struct work_struct *work)
-{
-	struct controlvm_message inmsg;
-	bool got_command = false;
-	bool handle_command_failed = false;
-
-	/* make sure visorbus server is registered for controlvm callbacks */
-	if (visorchipset_visorbusregwait && !visorbusregistered)
-		goto cleanup;
-
-	while (visorchannel_signalremove(controlvm_channel,
-					 CONTROLVM_QUEUE_RESPONSE,
-					 &inmsg))
-		;
-	if (!got_command) {
-		if (controlvm_pending_msg_valid) {
-			/* we throttled processing of a prior
-			* msg, so try to process it again
-			* rather than reading a new one
-			*/
-			inmsg = controlvm_pending_msg;
-			controlvm_pending_msg_valid = false;
-			got_command = true;
-		} else {
-			got_command = read_controlvm_event(&inmsg);
-		}
-	}
-
-	handle_command_failed = false;
-	while (got_command && (!handle_command_failed)) {
-		most_recent_message_jiffies = jiffies;
-		if (handle_command(inmsg,
-				   visorchannel_get_physaddr
-				   (controlvm_channel)))
-			got_command = read_controlvm_event(&inmsg);
-		else {
-			/* this is a scenario where throttling
-			* is required, but probably NOT an
-			* error...; we stash the current
-			* controlvm msg so we will attempt to
-			* reprocess it on our next loop
-			*/
-			handle_command_failed = true;
-			controlvm_pending_msg = inmsg;
-			controlvm_pending_msg_valid = true;
-		}
-	}
-
-	/* parahotplug_worker */
-	parahotplug_process_list();
-
-cleanup:
-
-	if (time_after(jiffies,
-		       most_recent_message_jiffies + (HZ * MIN_IDLE_SECONDS))) {
-		/* it's been longer than MIN_IDLE_SECONDS since we
-		* processed our last controlvm message; slow down the
-		* polling
-		*/
-		if (poll_jiffies != POLLJIFFIES_CONTROLVMCHANNEL_SLOW)
-			poll_jiffies = POLLJIFFIES_CONTROLVMCHANNEL_SLOW;
-	} else {
-		if (poll_jiffies != POLLJIFFIES_CONTROLVMCHANNEL_FAST)
-			poll_jiffies = POLLJIFFIES_CONTROLVMCHANNEL_FAST;
-	}
-
-	schedule_delayed_work(&periodic_controlvm_work, poll_jiffies);
-}
-
-static void
 setup_crash_devices_work_queue(struct work_struct *work)
 {
 	struct controlvm_message local_crash_bus_msg;
@@ -1874,13 +1540,6 @@ setup_crash_devices_work_queue(struct work_struct *work)
 	u32 local_crash_msg_offset;
 	u16 local_crash_msg_count;
 
-	/* make sure visorbus is registered for controlvm callbacks */
-	if (visorchipset_visorbusregwait && !visorbusregistered) {
-		poll_jiffies = POLLJIFFIES_CONTROLVMCHANNEL_SLOW;
-		schedule_delayed_work(&periodic_controlvm_work, poll_jiffies);
-		return;
-	}
-
 	POSTCODE_LINUX_2(CRASH_DEV_ENTRY_PC, POSTCODE_SEVERITY_INFO);
 
 	/* send init chipset msg */
@@ -1958,7 +1617,7 @@ setup_crash_devices_work_queue(struct work_struct *work)
 	POSTCODE_LINUX_2(CRASH_DEV_EXIT_PC, POSTCODE_SEVERITY_INFO);
 }
 
-static void
+void
 bus_create_response(struct visor_device *bus_info, int response)
 {
 	if (response >= 0)
@@ -1971,7 +1630,7 @@ bus_create_response(struct visor_device *bus_info, int response)
 	bus_info->pending_msg_hdr = NULL;
 }
 
-static void
+void
 bus_destroy_response(struct visor_device *bus_info, int response)
 {
 	bus_responder(CONTROLVM_BUS_DESTROY, bus_info->pending_msg_hdr,
@@ -1981,7 +1640,7 @@ bus_destroy_response(struct visor_device *bus_info, int response)
 	bus_info->pending_msg_hdr = NULL;
 }
 
-static void
+void
 device_create_response(struct visor_device *dev_info, int response)
 {
 	if (response >= 0)
@@ -1994,7 +1653,7 @@ device_create_response(struct visor_device *dev_info, int response)
 	dev_info->pending_msg_hdr = NULL;
 }
 
-static void
+void
 device_destroy_response(struct visor_device *dev_info, int response)
 {
 	device_responder(CONTROLVM_DEVICE_DESTROY, dev_info->pending_msg_hdr,
@@ -2004,9 +1663,9 @@ device_destroy_response(struct visor_device *dev_info, int response)
 	dev_info->pending_msg_hdr = NULL;
 }
 
-static void
-visorchipset_device_pause_response(struct visor_device *dev_info,
-				   int response)
+void
+device_pause_response(struct visor_device *dev_info,
+		      int response)
 {
 	device_changestate_responder(CONTROLVM_DEVICE_CHANGESTATE,
 				     dev_info, response,
@@ -2016,7 +1675,7 @@ visorchipset_device_pause_response(struct visor_device *dev_info,
 	dev_info->pending_msg_hdr = NULL;
 }
 
-static void
+void
 device_resume_response(struct visor_device *dev_info, int response)
 {
 	device_changestate_responder(CONTROLVM_DEVICE_CHANGESTATE,
@@ -2027,40 +1686,6 @@ device_resume_response(struct visor_device *dev_info, int response)
 	dev_info->pending_msg_hdr = NULL;
 }
 
-/* The parahotplug/devicedisabled interface gets called by our support script
- * when an SR-IOV device has been shut down. The ID is passed to the script
- * and then passed back when the device has been removed.
- */
-static ssize_t devicedisabled_store(struct device *dev,
-				    struct device_attribute *attr,
-				    const char *buf, size_t count)
-{
-	unsigned int id;
-
-	if (kstrtouint(buf, 10, &id))
-		return -EINVAL;
-
-	parahotplug_request_complete(id, 0);
-	return count;
-}
-
-/* The parahotplug/deviceenabled interface gets called by our support script
- * when an SR-IOV device has been recovered. The ID is passed to the script
- * and then passed back when the device has been brought back up.
- */
-static ssize_t deviceenabled_store(struct device *dev,
-				   struct device_attribute *attr,
-				   const char *buf, size_t count)
-{
-	unsigned int id;
-
-	if (kstrtouint(buf, 10, &id))
-		return -EINVAL;
-
-	parahotplug_request_complete(id, 1);
-	return count;
-}
-
 static int
 visorchipset_mmap(struct file *file, struct vm_area_struct *vma)
 {
@@ -2191,6 +1816,298 @@ visorchipset_file_cleanup(dev_t major_dev)
 	unregister_chrdev_region(major_dev, 1);
 }
 
+static struct parser_context *
+parser_init_byte_stream(u64 addr, u32 bytes, bool local, bool *retry)
+{
+	int allocbytes = sizeof(struct parser_context) + bytes;
+	struct parser_context *ctx;
+
+	if (retry)
+		*retry = false;
+
+	/*
+	 * alloc an 0 extra byte to ensure payload is
+	 * '\0'-terminated
+	 */
+	allocbytes++;
+	if ((controlvm_payload_bytes_buffered + bytes)
+	    > MAX_CONTROLVM_PAYLOAD_BYTES) {
+		if (retry)
+			*retry = true;
+		return NULL;
+	}
+	ctx = kzalloc(allocbytes, GFP_KERNEL | __GFP_NORETRY);
+	if (!ctx) {
+		if (retry)
+			*retry = true;
+		return NULL;
+	}
+
+	ctx->allocbytes = allocbytes;
+	ctx->param_bytes = bytes;
+	ctx->curr = NULL;
+	ctx->bytes_remaining = 0;
+	ctx->byte_stream = false;
+	if (local) {
+		void *p;
+
+		if (addr > virt_to_phys(high_memory - 1))
+			goto err_finish_ctx;
+		p = __va((unsigned long)(addr));
+		memcpy(ctx->data, p, bytes);
+	} else {
+		void *mapping = memremap(addr, bytes, MEMREMAP_WB);
+
+		if (!mapping)
+			goto err_finish_ctx;
+		memcpy(ctx->data, mapping, bytes);
+		memunmap(mapping);
+	}
+
+	ctx->byte_stream = true;
+	controlvm_payload_bytes_buffered += ctx->param_bytes;
+
+	return ctx;
+
+err_finish_ctx:
+	parser_done(ctx);
+	return NULL;
+}
+
+/**
+ * handle_command() - process a controlvm message
+ * @inmsg:        the message to process
+ * @channel_addr: address of the controlvm channel
+ *
+ * Return:
+ *    false - this function will return false only in the case where the
+ *            controlvm message was NOT processed, but processing must be
+ *            retried before reading the next controlvm message; a
+ *            scenario where this can occur is when we need to throttle
+ *            the allocation of memory in which to copy out controlvm
+ *            payload data
+ *    true  - processing of the controlvm message completed,
+ *            either successfully or with an error
+ */
+static bool
+handle_command(struct controlvm_message inmsg, u64 channel_addr)
+{
+	struct controlvm_message_packet *cmd = &inmsg.cmd;
+	u64 parm_addr;
+	u32 parm_bytes;
+	struct parser_context *parser_ctx = NULL;
+	bool local_addr;
+	struct controlvm_message ackmsg;
+
+	/* create parsing context if necessary */
+	local_addr = (inmsg.hdr.flags.test_message == 1);
+	if (channel_addr == 0)
+		return true;
+	parm_addr = channel_addr + inmsg.hdr.payload_vm_offset;
+	parm_bytes = inmsg.hdr.payload_bytes;
+
+	/*
+	 * Parameter and channel addresses within test messages actually lie
+	 * within our OS-controlled memory. We need to know that, because it
+	 * makes a difference in how we compute the virtual address.
+	 */
+	if (parm_addr && parm_bytes) {
+		bool retry = false;
+
+		parser_ctx =
+		    parser_init_byte_stream(parm_addr, parm_bytes,
+					    local_addr, &retry);
+		if (!parser_ctx && retry)
+			return false;
+	}
+
+	if (!local_addr) {
+		controlvm_init_response(&ackmsg, &inmsg.hdr,
+					CONTROLVM_RESP_SUCCESS);
+		if (controlvm_channel)
+			visorchannel_signalinsert(controlvm_channel,
+						  CONTROLVM_QUEUE_ACK,
+						  &ackmsg);
+	}
+	switch (inmsg.hdr.id) {
+	case CONTROLVM_CHIPSET_INIT:
+		chipset_init(&inmsg);
+		break;
+	case CONTROLVM_BUS_CREATE:
+		bus_create(&inmsg);
+		break;
+	case CONTROLVM_BUS_DESTROY:
+		bus_destroy(&inmsg);
+		break;
+	case CONTROLVM_BUS_CONFIGURE:
+		bus_configure(&inmsg, parser_ctx);
+		break;
+	case CONTROLVM_DEVICE_CREATE:
+		my_device_create(&inmsg);
+		break;
+	case CONTROLVM_DEVICE_CHANGESTATE:
+		if (cmd->device_change_state.flags.phys_device) {
+			parahotplug_process_message(&inmsg);
+		} else {
+			/*
+			 * save the hdr and cmd structures for later use
+			 * when sending back the response to Command
+			 */
+			my_device_changestate(&inmsg);
+			break;
+		}
+		break;
+	case CONTROLVM_DEVICE_DESTROY:
+		my_device_destroy(&inmsg);
+		break;
+	case CONTROLVM_DEVICE_CONFIGURE:
+		/* no op for now, just send a respond that we passed */
+		if (inmsg.hdr.flags.response_expected)
+			controlvm_respond(&inmsg.hdr, CONTROLVM_RESP_SUCCESS);
+		break;
+	case CONTROLVM_CHIPSET_READY:
+		chipset_ready(&inmsg.hdr);
+		break;
+	case CONTROLVM_CHIPSET_SELFTEST:
+		chipset_selftest(&inmsg.hdr);
+		break;
+	case CONTROLVM_CHIPSET_STOP:
+		chipset_notready(&inmsg.hdr);
+		break;
+	default:
+		if (inmsg.hdr.flags.response_expected)
+			controlvm_respond
+				(&inmsg.hdr,
+				 -CONTROLVM_RESP_ERROR_MESSAGE_ID_UNKNOWN);
+		break;
+	}
+
+	if (parser_ctx) {
+		parser_done(parser_ctx);
+		parser_ctx = NULL;
+	}
+	return true;
+}
+
+/**
+ * read_controlvm_event() - retreives the next message from the
+ *                          CONTROLVM_QUEUE_EVENT queue in the controlvm
+ *                          channel
+ * @msg: pointer to the retrieved message
+ *
+ * Return: true if a valid message was retrieved or false otherwise
+ */
+static bool
+read_controlvm_event(struct controlvm_message *msg)
+{
+	if (!visorchannel_signalremove(controlvm_channel,
+				       CONTROLVM_QUEUE_EVENT, msg)) {
+		/* got a message */
+		if (msg->hdr.flags.test_message == 1)
+			return false;
+		return true;
+	}
+	return false;
+}
+
+/**
+ * parahotplug_process_list() - remove any request from the list that's been on
+ *                              there too long and respond with an error
+ */
+static void
+parahotplug_process_list(void)
+{
+	struct list_head *pos;
+	struct list_head *tmp;
+
+	spin_lock(&parahotplug_request_list_lock);
+
+	list_for_each_safe(pos, tmp, &parahotplug_request_list) {
+		struct parahotplug_request *req =
+		    list_entry(pos, struct parahotplug_request, list);
+
+		if (!time_after_eq(jiffies, req->expiration))
+			continue;
+
+		list_del(pos);
+		if (req->msg.hdr.flags.response_expected)
+			controlvm_respond_physdev_changestate(
+				&req->msg.hdr,
+				CONTROLVM_RESP_ERROR_DEVICE_UDEV_TIMEOUT,
+				req->msg.cmd.device_change_state.state);
+		parahotplug_request_destroy(req);
+	}
+
+	spin_unlock(&parahotplug_request_list_lock);
+}
+
+static void
+controlvm_periodic_work(struct work_struct *work)
+{
+	struct controlvm_message inmsg;
+	bool got_command = false;
+	bool handle_command_failed = false;
+
+	while (!visorchannel_signalremove(controlvm_channel,
+					  CONTROLVM_QUEUE_RESPONSE,
+					  &inmsg))
+		;
+	if (!got_command) {
+		if (controlvm_pending_msg_valid) {
+			/*
+			 * we throttled processing of a prior
+			 * msg, so try to process it again
+			 * rather than reading a new one
+			 */
+			inmsg = controlvm_pending_msg;
+			controlvm_pending_msg_valid = false;
+			got_command = true;
+		} else {
+			got_command = read_controlvm_event(&inmsg);
+		}
+	}
+
+	handle_command_failed = false;
+	while (got_command && (!handle_command_failed)) {
+		most_recent_message_jiffies = jiffies;
+		if (handle_command(inmsg,
+				   visorchannel_get_physaddr
+				   (controlvm_channel)))
+			got_command = read_controlvm_event(&inmsg);
+		else {
+			/*
+			 * this is a scenario where throttling
+			 * is required, but probably NOT an
+			 * error...; we stash the current
+			 * controlvm msg so we will attempt to
+			 * reprocess it on our next loop
+			 */
+			handle_command_failed = true;
+			controlvm_pending_msg = inmsg;
+			controlvm_pending_msg_valid = true;
+		}
+	}
+
+	/* parahotplug_worker */
+	parahotplug_process_list();
+
+	if (time_after(jiffies,
+		       most_recent_message_jiffies + (HZ * MIN_IDLE_SECONDS))) {
+		/*
+		 * it's been longer than MIN_IDLE_SECONDS since we
+		 * processed our last controlvm message; slow down the
+		 * polling
+		 */
+		if (poll_jiffies != POLLJIFFIES_CONTROLVMCHANNEL_SLOW)
+			poll_jiffies = POLLJIFFIES_CONTROLVMCHANNEL_SLOW;
+	} else {
+		if (poll_jiffies != POLLJIFFIES_CONTROLVMCHANNEL_FAST)
+			poll_jiffies = POLLJIFFIES_CONTROLVMCHANNEL_FAST;
+	}
+
+	schedule_delayed_work(&periodic_controlvm_work, poll_jiffies);
+}
+
 static int
 visorchipset_init(struct acpi_device *acpi_device)
 {
@@ -2202,7 +2119,6 @@ visorchipset_init(struct acpi_device *acpi_device)
 	if (!addr)
 		goto error;
 
-	memset(&busdev_notifiers, 0, sizeof(busdev_notifiers));
 	memset(&controlvm_payload_info, 0, sizeof(controlvm_payload_info));
 
 	controlvm_channel = visorchannel_create_with_lock(addr, 0,
@@ -2341,15 +2257,10 @@ static void exit_unisys(void)
 module_param_named(major, visorchipset_major, int, S_IRUGO);
 MODULE_PARM_DESC(visorchipset_major,
 		 "major device number to use for the device node");
-module_param_named(visorbusregwait, visorchipset_visorbusregwait, int, S_IRUGO);
-MODULE_PARM_DESC(visorchipset_visorbusregwait,
-		 "1 to have the module wait for the visor bus to register");
 
 module_init(init_unisys);
 module_exit(exit_unisys);
 
 MODULE_AUTHOR("Unisys");
 MODULE_LICENSE("GPL");
-MODULE_DESCRIPTION("Supervisor chipset driver for service partition: ver "
-		   VERSION);
-MODULE_VERSION(VERSION);
+MODULE_DESCRIPTION("s-Par visorbus driver for virtual device buses");