Merge tag 'char-misc-4.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc

Pull char/misc driver updates from Greg KH:
 "Here is the big set of new char/misc driver drivers and features for
  4.12-rc1.

  There's lots of new drivers added this time around, new firmware
  drivers from Google, more auxdisplay drivers, extcon drivers, fpga
  drivers, and a bunch of other driver updates. Nothing major, except if
  you happen to have the hardware for these drivers, and then you will
  be happy :)

  All of these have been in linux-next for a while with no reported
  issues"

* tag 'char-misc-4.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (136 commits)
  firmware: google memconsole: Fix return value check in platform_memconsole_init()
  firmware: Google VPD: Fix return value check in vpd_platform_init()
  goldfish_pipe: fix build warning about using too much stack.
  goldfish_pipe: An implementation of more parallel pipe
  fpga fr br: update supported version numbers
  fpga: region: release FPGA region reference in error path
  fpga altera-hps2fpga: disable/unprepare clock on error in alt_fpga_bridge_probe()
  mei: drop the TODO from samples
  firmware: Google VPD sysfs driver
  firmware: Google VPD: import lib_vpd source files
  misc: lkdtm: Add volatile to intentional NULL pointer reference
  eeprom: idt_89hpesx: Add OF device ID table
  misc: ds1682: Add OF device ID table
  misc: tsl2550: Add OF device ID table
  w1: Remove unneeded use of assert() and remove w1_log.h
  w1: Use kernel common min() implementation
  uio_mf624: Align memory regions to page size and set correct offsets
  uio_mf624: Refactor memory info initialization
  uio: Allow handling of non page-aligned memory regions
  hangcheck-timer: Fix typo in comment
  ...

11 files changed, 90 insertions, 111 deletions

diff --git a/drivers/hv/channel.c b/drivers/hv/channel.c
index 321b883..736ac76 100644
--- a/drivers/hv/channel.c
+++ b/drivers/hv/channel.c
@@ -333,7 +333,7 @@ static int create_gpadl_header(void *kbuffer, u32 size,
 			 * Gpadl is u32 and we are using a pointer which could
 			 * be 64-bit
 			 * This is governed by the guest/host protocol and
-			 * so the hypervisor gurantees that this is ok.
+			 * so the hypervisor guarantees that this is ok.
 			 */
 			for (i = 0; i < pfncurr; i++)
 				gpadl_body->pfn[i] = slow_virt_to_phys(
@@ -380,7 +380,7 @@ nomem:
 }
 
 /*
- * vmbus_establish_gpadl - Estabish a GPADL for the specified buffer
+ * vmbus_establish_gpadl - Establish a GPADL for the specified buffer
  *
  * @channel: a channel
  * @kbuffer: from kmalloc or vmalloc
@@ -731,7 +731,7 @@ int vmbus_sendpacket_pagebuffer_ctl(struct vmbus_channel *channel,
 	/* Setup the descriptor */
 	desc.type = VM_PKT_DATA_USING_GPA_DIRECT;
 	desc.flags = flags;
-	desc.dataoffset8 = descsize >> 3; /* in 8-bytes grandularity */
+	desc.dataoffset8 = descsize >> 3; /* in 8-bytes granularity */
 	desc.length8 = (u16)(packetlen_aligned >> 3);
 	desc.transactionid = requestid;
 	desc.rangecount = pagecount;
@@ -792,7 +792,7 @@ int vmbus_sendpacket_mpb_desc(struct vmbus_channel *channel,
 	/* Setup the descriptor */
 	desc->type = VM_PKT_DATA_USING_GPA_DIRECT;
 	desc->flags = VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED;
-	desc->dataoffset8 = desc_size >> 3; /* in 8-bytes grandularity */
+	desc->dataoffset8 = desc_size >> 3; /* in 8-bytes granularity */
 	desc->length8 = (u16)(packetlen_aligned >> 3);
 	desc->transactionid = requestid;
 	desc->rangecount = 1;
@@ -842,7 +842,7 @@ int vmbus_sendpacket_multipagebuffer(struct vmbus_channel *channel,
 	/* Setup the descriptor */
 	desc.type = VM_PKT_DATA_USING_GPA_DIRECT;
 	desc.flags = VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED;
-	desc.dataoffset8 = descsize >> 3; /* in 8-bytes grandularity */
+	desc.dataoffset8 = descsize >> 3; /* in 8-bytes granularity */
 	desc.length8 = (u16)(packetlen_aligned >> 3);
 	desc.transactionid = requestid;
 	desc.rangecount = 1;
diff --git a/drivers/hv/channel_mgmt.c b/drivers/hv/channel_mgmt.c
index fbcb063..735f936 100644
--- a/drivers/hv/channel_mgmt.c
+++ b/drivers/hv/channel_mgmt.c
@@ -1080,30 +1080,30 @@ static void vmbus_onversion_response(
 }
 
 /* Channel message dispatch table */
-struct vmbus_channel_message_table_entry
-	channel_message_table[CHANNELMSG_COUNT] = {
-	{CHANNELMSG_INVALID,			0, NULL},
-	{CHANNELMSG_OFFERCHANNEL,		0, vmbus_onoffer},
-	{CHANNELMSG_RESCIND_CHANNELOFFER,	0, vmbus_onoffer_rescind},
-	{CHANNELMSG_REQUESTOFFERS,		0, NULL},
-	{CHANNELMSG_ALLOFFERS_DELIVERED,	1, vmbus_onoffers_delivered},
-	{CHANNELMSG_OPENCHANNEL,		0, NULL},
-	{CHANNELMSG_OPENCHANNEL_RESULT,		1, vmbus_onopen_result},
-	{CHANNELMSG_CLOSECHANNEL,		0, NULL},
-	{CHANNELMSG_GPADL_HEADER,		0, NULL},
-	{CHANNELMSG_GPADL_BODY,			0, NULL},
-	{CHANNELMSG_GPADL_CREATED,		1, vmbus_ongpadl_created},
-	{CHANNELMSG_GPADL_TEARDOWN,		0, NULL},
-	{CHANNELMSG_GPADL_TORNDOWN,		1, vmbus_ongpadl_torndown},
-	{CHANNELMSG_RELID_RELEASED,		0, NULL},
-	{CHANNELMSG_INITIATE_CONTACT,		0, NULL},
-	{CHANNELMSG_VERSION_RESPONSE,		1, vmbus_onversion_response},
-	{CHANNELMSG_UNLOAD,			0, NULL},
-	{CHANNELMSG_UNLOAD_RESPONSE,		1, vmbus_unload_response},
-	{CHANNELMSG_18,				0, NULL},
-	{CHANNELMSG_19,				0, NULL},
-	{CHANNELMSG_20,				0, NULL},
-	{CHANNELMSG_TL_CONNECT_REQUEST,		0, NULL},
+const struct vmbus_channel_message_table_entry
+channel_message_table[CHANNELMSG_COUNT] = {
+	{ CHANNELMSG_INVALID,			0, NULL },
+	{ CHANNELMSG_OFFERCHANNEL,		0, vmbus_onoffer },
+	{ CHANNELMSG_RESCIND_CHANNELOFFER,	0, vmbus_onoffer_rescind },
+	{ CHANNELMSG_REQUESTOFFERS,		0, NULL },
+	{ CHANNELMSG_ALLOFFERS_DELIVERED,	1, vmbus_onoffers_delivered },
+	{ CHANNELMSG_OPENCHANNEL,		0, NULL },
+	{ CHANNELMSG_OPENCHANNEL_RESULT,	1, vmbus_onopen_result },
+	{ CHANNELMSG_CLOSECHANNEL,		0, NULL },
+	{ CHANNELMSG_GPADL_HEADER,		0, NULL },
+	{ CHANNELMSG_GPADL_BODY,		0, NULL },
+	{ CHANNELMSG_GPADL_CREATED,		1, vmbus_ongpadl_created },
+	{ CHANNELMSG_GPADL_TEARDOWN,		0, NULL },
+	{ CHANNELMSG_GPADL_TORNDOWN,		1, vmbus_ongpadl_torndown },
+	{ CHANNELMSG_RELID_RELEASED,		0, NULL },
+	{ CHANNELMSG_INITIATE_CONTACT,		0, NULL },
+	{ CHANNELMSG_VERSION_RESPONSE,		1, vmbus_onversion_response },
+	{ CHANNELMSG_UNLOAD,			0, NULL },
+	{ CHANNELMSG_UNLOAD_RESPONSE,		1, vmbus_unload_response },
+	{ CHANNELMSG_18,			0, NULL },
+	{ CHANNELMSG_19,			0, NULL },
+	{ CHANNELMSG_20,			0, NULL },
+	{ CHANNELMSG_TL_CONNECT_REQUEST,	0, NULL },
 };
 
 /*
diff --git a/drivers/hv/connection.c b/drivers/hv/connection.c
index a8366fe..fce27fb 100644
--- a/drivers/hv/connection.c
+++ b/drivers/hv/connection.c
@@ -296,44 +296,47 @@ struct vmbus_channel *relid2channel(u32 relid)
 
 /*
  * vmbus_on_event - Process a channel event notification
+ *
+ * For batched channels (default) optimize host to guest signaling
+ * by ensuring:
+ * 1. While reading the channel, we disable interrupts from host.
+ * 2. Ensure that we process all posted messages from the host
+ *    before returning from this callback.
+ * 3. Once we return, enable signaling from the host. Once this
+ *    state is set we check to see if additional packets are
+ *    available to read. In this case we repeat the process.
+ *    If this tasklet has been running for a long time
+ *    then reschedule ourselves.
  */
 void vmbus_on_event(unsigned long data)
 {
 	struct vmbus_channel *channel = (void *) data;
-	void (*callback_fn)(void *);
+	unsigned long time_limit = jiffies + 2;
 
-	/*
-	 * A channel once created is persistent even when there
-	 * is no driver handling the device. An unloading driver
-	 * sets the onchannel_callback to NULL on the same CPU
-	 * as where this interrupt is handled (in an interrupt context).
-	 * Thus, checking and invoking the driver specific callback takes
-	 * care of orderly unloading of the driver.
-	 */
-	callback_fn = READ_ONCE(channel->onchannel_callback);
-	if (unlikely(callback_fn == NULL))
-		return;
-
-	(*callback_fn)(channel->channel_callback_context);
-
-	if (channel->callback_mode == HV_CALL_BATCHED) {
-		/*
-		 * This callback reads the messages sent by the host.
-		 * We can optimize host to guest signaling by ensuring:
-		 * 1. While reading the channel, we disable interrupts from
-		 *    host.
-		 * 2. Ensure that we process all posted messages from the host
-		 *    before returning from this callback.
-		 * 3. Once we return, enable signaling from the host. Once this
-		 *    state is set we check to see if additional packets are
-		 *    available to read. In this case we repeat the process.
+	do {
+		void (*callback_fn)(void *);
+
+		/* A channel once created is persistent even when
+		 * there is no driver handling the device. An
+		 * unloading driver sets the onchannel_callback to NULL.
 		 */
-		if (hv_end_read(&channel->inbound) != 0) {
-			hv_begin_read(&channel->inbound);
+		callback_fn = READ_ONCE(channel->onchannel_callback);
+		if (unlikely(callback_fn == NULL))
+			return;
 
-			tasklet_schedule(&channel->callback_event);
-		}
-	}
+		(*callback_fn)(channel->channel_callback_context);
+
+		if (channel->callback_mode != HV_CALL_BATCHED)
+			return;
+
+		if (likely(hv_end_read(&channel->inbound) == 0))
+			return;
+
+		hv_begin_read(&channel->inbound);
+	} while (likely(time_before(jiffies, time_limit)));
+
+	/* The time limit (2 jiffies) has been reached */
+	tasklet_schedule(&channel->callback_event);
 }
 
 /*
diff --git a/drivers/hv/hv.c b/drivers/hv/hv.c
index 665a64f..12e7bae 100644
--- a/drivers/hv/hv.c
+++ b/drivers/hv/hv.c
@@ -254,7 +254,10 @@ int hv_synic_init(unsigned int cpu)
 	shared_sint.as_uint64 = 0;
 	shared_sint.vector = HYPERVISOR_CALLBACK_VECTOR;
 	shared_sint.masked = false;
-	shared_sint.auto_eoi = true;
+	if (ms_hyperv.hints & HV_X64_DEPRECATING_AEOI_RECOMMENDED)
+		shared_sint.auto_eoi = false;
+	else
+		shared_sint.auto_eoi = true;
 
 	hv_set_synint_state(HV_X64_MSR_SINT0 + VMBUS_MESSAGE_SINT,
 			    shared_sint.as_uint64);
diff --git a/drivers/hv/hv_balloon.c b/drivers/hv/hv_balloon.c
index 5fd03e5..f5728de 100644
--- a/drivers/hv/hv_balloon.c
+++ b/drivers/hv/hv_balloon.c
@@ -722,8 +722,6 @@ static void hv_mem_hot_add(unsigned long start, unsigned long size,
 						    5*HZ);
 		post_status(&dm_device);
 	}
-
-	return;
 }
 
 static void hv_online_page(struct page *pg)
diff --git a/drivers/hv/hv_fcopy.c b/drivers/hv/hv_fcopy.c
index a5596a6..daa75bd 100644
--- a/drivers/hv/hv_fcopy.c
+++ b/drivers/hv/hv_fcopy.c
@@ -186,8 +186,6 @@ static void fcopy_send_data(struct work_struct *dummy)
 		}
 	}
 	kfree(smsg_out);
-
-	return;
 }
 
 /*
diff --git a/drivers/hv/hv_kvp.c b/drivers/hv/hv_kvp.c
index a1adfe2..e99ff2d 100644
--- a/drivers/hv/hv_kvp.c
+++ b/drivers/hv/hv_kvp.c
@@ -69,7 +69,7 @@ static const int fw_versions[] = {
  *
  * While the request/response protocol is guaranteed by the host, we further
  * ensure this by serializing packet processing in this driver - we do not
- * read additional packets from the VMBUs until the current packet is fully
+ * read additional packets from the VMBUS until the current packet is fully
  * handled.
  */
 
@@ -397,7 +397,7 @@ kvp_send_key(struct work_struct *dummy)
 	 * the max lengths specified. We will however, reserve room
 	 * for the string terminating character - in the utf16s_utf8s()
 	 * function we limit the size of the buffer where the converted
-	 * string is placed to HV_KVP_EXCHANGE_MAX_*_SIZE -1 to gaurantee
+	 * string is placed to HV_KVP_EXCHANGE_MAX_*_SIZE -1 to guarantee
 	 * that the strings can be properly terminated!
 	 */
 
@@ -483,8 +483,6 @@ kvp_send_key(struct work_struct *dummy)
 	}
 
 	kfree(message);
-
-	return;
 }
 
 /*
@@ -533,7 +531,7 @@ kvp_respond_to_host(struct hv_kvp_msg *msg_to_host, int error)
 	 */
 	if (error) {
 		/*
-		 * Something failed or we have timedout;
+		 * Something failed or we have timed out;
 		 * terminate the current host-side iteration.
 		 */
 		goto response_done;
@@ -607,8 +605,8 @@ response_done:
  * This callback is invoked when we get a KVP message from the host.
  * The host ensures that only one KVP transaction can be active at a time.
  * KVP implementation in Linux needs to forward the key to a user-mde
- * component to retrive the corresponding value. Consequently, we cannot
- * respond to the host in the conext of this callback. Since the host
+ * component to retrieve the corresponding value. Consequently, we cannot
+ * respond to the host in the context of this callback. Since the host
  * guarantees that at most only one transaction can be active at a time,
  * we stash away the transaction state in a set of global variables.
  */
diff --git a/drivers/hv/hv_snapshot.c b/drivers/hv/hv_snapshot.c
index e659d1b..6831efd 100644
--- a/drivers/hv/hv_snapshot.c
+++ b/drivers/hv/hv_snapshot.c
@@ -212,8 +212,6 @@ static void vss_send_op(void)
 	}
 
 	kfree(vss_msg);
-
-	return;
 }
 
 static void vss_handle_request(struct work_struct *dummy)
diff --git a/drivers/hv/hyperv_vmbus.h b/drivers/hv/hyperv_vmbus.h
index 884f83b..6113e91 100644
--- a/drivers/hv/hyperv_vmbus.h
+++ b/drivers/hv/hyperv_vmbus.h
@@ -218,8 +218,8 @@ struct hv_per_cpu_context {
 
 struct hv_context {
 	/* We only support running on top of Hyper-V
-	* So at this point this really can only contain the Hyper-V ID
-	*/
+	 * So at this point this really can only contain the Hyper-V ID
+	 */
 	u64 guestid;
 
 	void *tsc_page;
@@ -248,14 +248,6 @@ struct hv_context {
 
 extern struct hv_context hv_context;
 
-struct hv_ring_buffer_debug_info {
-	u32 current_interrupt_mask;
-	u32 current_read_index;
-	u32 current_write_index;
-	u32 bytes_avail_toread;
-	u32 bytes_avail_towrite;
-};
-
 /* Hv Interface */
 
 extern int hv_init(void);
@@ -289,9 +281,6 @@ int hv_ringbuffer_read(struct vmbus_channel *channel,
 		       void *buffer, u32 buflen, u32 *buffer_actual_len,
 		       u64 *requestid, bool raw);
 
-void hv_ringbuffer_get_debuginfo(const struct hv_ring_buffer_info *ring_info,
-				 struct hv_ring_buffer_debug_info *debug_info);
-
 /*
  * Maximum channels is determined by the size of the interrupt page
  * which is PAGE_SIZE. 1/2 of PAGE_SIZE is for send endpoint interrupt
@@ -376,7 +365,7 @@ struct vmbus_channel_message_table_entry {
 	void (*message_handler)(struct vmbus_channel_message_header *msg);
 };
 
-extern struct vmbus_channel_message_table_entry
+extern const struct vmbus_channel_message_table_entry
 	channel_message_table[CHANNELMSG_COUNT];
 
 
@@ -403,17 +392,17 @@ int vmbus_post_msg(void *buffer, size_t buflen, bool can_sleep);
 void vmbus_on_event(unsigned long data);
 void vmbus_on_msg_dpc(unsigned long data);
 
-int hv_kvp_init(struct hv_util_service *);
+int hv_kvp_init(struct hv_util_service *srv);
 void hv_kvp_deinit(void);
-void hv_kvp_onchannelcallback(void *);
+void hv_kvp_onchannelcallback(void *context);
 
-int hv_vss_init(struct hv_util_service *);
+int hv_vss_init(struct hv_util_service *srv);
 void hv_vss_deinit(void);
-void hv_vss_onchannelcallback(void *);
+void hv_vss_onchannelcallback(void *context);
 
-int hv_fcopy_init(struct hv_util_service *);
+int hv_fcopy_init(struct hv_util_service *srv);
 void hv_fcopy_deinit(void);
-void hv_fcopy_onchannelcallback(void *);
+void hv_fcopy_onchannelcallback(void *context);
 void vmbus_initiate_unload(bool crash);
 
 static inline void hv_poll_channel(struct vmbus_channel *channel,
diff --git a/drivers/hv/ring_buffer.c b/drivers/hv/ring_buffer.c
index c3f1a9e..1f450c3 100644
--- a/drivers/hv/ring_buffer.c
+++ b/drivers/hv/ring_buffer.c
@@ -75,8 +75,6 @@ static void hv_signal_on_write(u32 old_write, struct vmbus_channel *channel)
 	 */
 	if (old_write == READ_ONCE(rbi->ring_buffer->read_index))
 		vmbus_setevent(channel);
-
-	return;
 }
 
 /* Get the next write location for the specified ring buffer. */
@@ -210,6 +208,7 @@ void hv_ringbuffer_get_debuginfo(const struct hv_ring_buffer_info *ring_info,
 			ring_info->ring_buffer->interrupt_mask;
 	}
 }
+EXPORT_SYMBOL_GPL(hv_ringbuffer_get_debuginfo);
 
 /* Initialize the ring buffer. */
 int hv_ringbuffer_init(struct hv_ring_buffer_info *ring_info,
@@ -269,14 +268,13 @@ void hv_ringbuffer_cleanup(struct hv_ring_buffer_info *ring_info)
 int hv_ringbuffer_write(struct vmbus_channel *channel,
 			const struct kvec *kv_list, u32 kv_count)
 {
-	int i = 0;
+	int i;
 	u32 bytes_avail_towrite;
-	u32 totalbytes_towrite = 0;
-
+	u32 totalbytes_towrite = sizeof(u64);
 	u32 next_write_location;
 	u32 old_write;
-	u64 prev_indices = 0;
-	unsigned long flags = 0;
+	u64 prev_indices;
+	unsigned long flags;
 	struct hv_ring_buffer_info *outring_info = &channel->outbound;
 
 	if (channel->rescind)
@@ -285,8 +283,6 @@ int hv_ringbuffer_write(struct vmbus_channel *channel,
 	for (i = 0; i < kv_count; i++)
 		totalbytes_towrite += kv_list[i].iov_len;
 
-	totalbytes_towrite += sizeof(u64);
-
 	spin_lock_irqsave(&outring_info->ring_lock, flags);
 
 	bytes_avail_towrite = hv_get_bytes_to_write(outring_info);
@@ -349,18 +345,16 @@ int hv_ringbuffer_read(struct vmbus_channel *channel,
 		       u64 *requestid, bool raw)
 {
 	u32 bytes_avail_toread;
-	u32 next_read_location = 0;
+	u32 next_read_location;
 	u64 prev_indices = 0;
 	struct vmpacket_descriptor desc;
 	u32 offset;
 	u32 packetlen;
-	int ret = 0;
 	struct hv_ring_buffer_info *inring_info = &channel->inbound;
 
 	if (buflen <= 0)
 		return -EINVAL;
 
-
 	*buffer_actual_len = 0;
 	*requestid = 0;
 
@@ -371,7 +365,7 @@ int hv_ringbuffer_read(struct vmbus_channel *channel,
 		 * No error is set when there is even no header, drivers are
 		 * supposed to analyze buffer_actual_len.
 		 */
-		return ret;
+		return 0;
 	}
 
 	init_cached_read_index(inring_info);
@@ -417,7 +411,7 @@ int hv_ringbuffer_read(struct vmbus_channel *channel,
 
 	hv_signal_on_read(channel);
 
-	return ret;
+	return 0;
 }
 
 /*
diff --git a/drivers/hv/vmbus_drv.c b/drivers/hv/vmbus_drv.c
index 8370b9d..0087b49 100644
--- a/drivers/hv/vmbus_drv.c
+++ b/drivers/hv/vmbus_drv.c
@@ -787,8 +787,6 @@ static void vmbus_shutdown(struct device *child_device)
 
 	if (drv->shutdown)
 		drv->shutdown(dev);
-
-	return;
 }
 
 
@@ -855,7 +853,7 @@ void vmbus_on_msg_dpc(unsigned long data)
 	struct hv_message *msg = (struct hv_message *)page_addr +
 				  VMBUS_MESSAGE_SINT;
 	struct vmbus_channel_message_header *hdr;
-	struct vmbus_channel_message_table_entry *entry;
+	const struct vmbus_channel_message_table_entry *entry;
 	struct onmessage_work_context *ctx;
 	u32 message_type = msg->header.message_type;