[PATCH 00/17] staging: most: fix hdm-usb issues

[PATCH 00/17] staging: most: fix hdm-usb issues

[Christian Gromm]

This patch set is needed to fix issues of the hdm-usb module.

Christian Gromm (17):
  staging: most: hdm-usb: remove unused macro HW_RESYNC
  staging: most: hdm-usb: provide MBO status when freeing buffers
  staging: most: hdm-usb: fix clear halt processing
  staging: most: hdm-usb: stop core from submitting buffers in case of
    broken pipe
  staging: most: hdm-usb: add USB product id
  staging: most: hdm-usb: rename ID_INIC for consistency
  staging: most: hdm-usb: make use of is_channel_healthy flag
  staging: most: hdm-usb: remove redundant conditions
  staging: most: hdm-usb: simplify initialization of mbo->status.
  staging: most: hdm-usb: fix race between enqueue and most_stop_enqueue
  staging: most: hdm-usb: assign spinlock to local variable
  staging: most: hdm-usb: synchronize release of struct buf_anchor
  staging: most: hdm-usb: remove completion object
  staging: most: hdm-usb: remove redundant parenthesis
  staging: most: hdm-usb: init variables at declaration time
  staging: most: hdm-usb: remove unnecessary status assignment
  staging: most: hdm-usb: add support for new USB gadget

 drivers/staging/most/hdm-usb/hdm_usb.c | 282 +++++++++++++++------------------
 drivers/staging/most/mostcore/core.c   |  53 +++++--
 2 files changed, 166 insertions(+), 169 deletions(-)

-- 
1.9.1

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[PATCH 01/17] staging: most: hdm-usb: remove unused macro HW_RESYNC

[Christian Gromm]

This patch removes the macro HW_RESYNC that is not used anymore.

Signed-off-by: Andrey Shvetsov <andrey.shvetsov@k2l.de>
Signed-off-by: Christian Gromm <christian.gromm@microchip.com>
---
 drivers/staging/most/hdm-usb/hdm_usb.c | 1 -
 1 file changed, 1 deletion(-)

diff --git a/drivers/staging/most/hdm-usb/hdm_usb.c b/drivers/staging/most/hdm-usb/hdm_usb.c
index e63784d..79277dd 100644
--- a/drivers/staging/most/hdm-usb/hdm_usb.c
+++ b/drivers/staging/most/hdm-usb/hdm_usb.c
@@ -44,7 +44,6 @@
 #define USB_VENDOR_ID_SMSC	0x0424  /* VID: SMSC */
 #define USB_DEV_ID_BRDG		0xC001  /* PID: USB Bridge */
 #define USB_DEV_ID_INIC		0xCF18  /* PID: USB INIC */
-#define HW_RESYNC		0x0000
 /* DRCI Addresses */
 #define DRCI_REG_NI_STATE	0x0100
 #define DRCI_REG_PACKET_BW	0x0101
-- 
1.9.1

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[PATCH 02/17] staging: most: hdm-usb: provide MBO status when freeing buffers

[Christian Gromm]

This patch adds the additional status parameter to function
free_anchored_buffers. This allows to dispatch further processing based
on this flag.

Signed-off-by: Andrey Shvetsov <andrey.shvetsov@k2l.de>
Signed-off-by: Christian Gromm <christian.gromm@microchip.com>
---
 drivers/staging/most/hdm-usb/hdm_usb.c | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/drivers/staging/most/hdm-usb/hdm_usb.c b/drivers/staging/most/hdm-usb/hdm_usb.c
index 79277dd..bc2d174 100644
--- a/drivers/staging/most/hdm-usb/hdm_usb.c
+++ b/drivers/staging/most/hdm-usb/hdm_usb.c
@@ -190,8 +190,10 @@ static inline int drci_wr_reg(struct usb_device *dev, u16 reg, u16 data)
  * free_anchored_buffers - free device's anchored items
  * @mdev: the device
  * @channel: channel ID
+ * @status: status of MBO termination
  */
-static void free_anchored_buffers(struct most_dev *mdev, unsigned int channel)
+static void free_anchored_buffers(struct most_dev *mdev, unsigned int channel,
+				  enum mbo_status_flags status)
 {
 	struct mbo *mbo;
 	struct buf_anchor *anchor, *tmp;
@@ -212,7 +214,7 @@ static void free_anchored_buffers(struct most_dev *mdev, unsigned int channel)
 				wait_for_completion(&anchor->urb_compl);
 			}
 			if ((mbo) && (mbo->complete)) {
-				mbo->status = MBO_E_CLOSE;
+				mbo->status = status;
 				mbo->processed_length = 0;
 				mbo->complete(mbo);
 			}
@@ -288,7 +290,7 @@ static int hdm_poison_channel(struct most_interface *iface, int channel)
 	mdev->is_channel_healthy[channel] = false;
 
 	mutex_lock(&mdev->io_mutex);
-	free_anchored_buffers(mdev, channel);
+	free_anchored_buffers(mdev, channel, MBO_E_CLOSE);
 	if (mdev->padding_active[channel])
 		mdev->padding_active[channel] = false;
 
-- 
1.9.1

[PATCH 03/17] staging: most: hdm-usb: fix clear halt processing

[Christian Gromm]

This patch is needed to ensure that submitted URBs get unlinked before
the driver calls usb_clear_halt(). Since the halt condition of an USB
endpoint is channel related, the work_struct is moved from a buffer
basis to a channel basis.

Signed-off-by: Christian Gromm <christian.gromm@microchip.com>
---
 drivers/staging/most/hdm-usb/hdm_usb.c | 62 ++++++++++++++++------------------
 1 file changed, 29 insertions(+), 33 deletions(-)

diff --git a/drivers/staging/most/hdm-usb/hdm_usb.c b/drivers/staging/most/hdm-usb/hdm_usb.c
index bc2d174..8f1c096 100644
--- a/drivers/staging/most/hdm-usb/hdm_usb.c
+++ b/drivers/staging/most/hdm-usb/hdm_usb.c
@@ -65,19 +65,15 @@
 /**
  * struct buf_anchor - used to create a list of pending URBs
  * @urb: pointer to USB request block
- * @clear_work_obj:
  * @list: linked list
  * @urb_completion:
  */
 struct buf_anchor {
 	struct urb *urb;
-	struct work_struct clear_work_obj;
 	struct list_head list;
 	struct completion urb_compl;
 };
 
-#define to_buf_anchor(w) container_of(w, struct buf_anchor, clear_work_obj)
-
 /**
  * struct most_dci_obj - Direct Communication Interface
  * @kobj:position in sysfs
@@ -90,6 +86,17 @@ struct most_dci_obj {
 
 #define to_dci_obj(p) container_of(p, struct most_dci_obj, kobj)
 
+struct most_dev;
+
+struct clear_hold_work {
+	struct work_struct ws;
+	struct most_dev *mdev;
+	unsigned int channel;
+	int pipe;
+};
+
+#define to_clear_hold_work(w) container_of(w, struct clear_hold_work, ws)
+
 /**
  * struct most_dev - holds all usb interface specific stuff
  * @parent: parent object in sysfs
@@ -126,6 +133,7 @@ struct most_dev {
 	spinlock_t anchor_list_lock[MAX_NUM_ENDPOINTS];
 	bool padding_active[MAX_NUM_ENDPOINTS];
 	bool is_channel_healthy[MAX_NUM_ENDPOINTS];
+	struct clear_hold_work clear_work[MAX_NUM_ENDPOINTS];
 	struct list_head *anchor_list;
 	struct mutex io_mutex;
 	struct timer_list link_stat_timer;
@@ -222,7 +230,6 @@ static void free_anchored_buffers(struct most_dev *mdev, unsigned int channel,
 		}
 		spin_lock_irqsave(&mdev->anchor_list_lock[channel], flags);
 		list_del(&anchor->list);
-		cancel_work_sync(&anchor->clear_work_obj);
 		kfree(anchor);
 	}
 	spin_unlock_irqrestore(&mdev->anchor_list_lock[channel], flags);
@@ -289,6 +296,8 @@ static int hdm_poison_channel(struct most_interface *iface, int channel)
 
 	mdev->is_channel_healthy[channel] = false;
 
+	cancel_work_sync(&mdev->clear_work[channel].ws);
+
 	mutex_lock(&mdev->io_mutex);
 	free_anchored_buffers(mdev, channel, MBO_E_CLOSE);
 	if (mdev->padding_active[channel])
@@ -409,9 +418,8 @@ static void hdm_write_completion(struct urb *urb)
 			dev_warn(dev, "Broken OUT pipe detected\n");
 			most_stop_enqueue(&mdev->iface, channel);
 			mbo->status = MBO_E_INVAL;
-			usb_unlink_urb(urb);
-			INIT_WORK(&anchor->clear_work_obj, wq_clear_halt);
-			schedule_work(&anchor->clear_work_obj);
+			mdev->clear_work[channel].pipe = urb->pipe;
+			schedule_work(&mdev->clear_work[channel].ws);
 			return;
 		case -ENODEV:
 		case -EPROTO:
@@ -573,9 +581,8 @@ static void hdm_read_completion(struct urb *urb)
 		case -EPIPE:
 			dev_warn(dev, "Broken IN pipe detected\n");
 			mbo->status = MBO_E_INVAL;
-			usb_unlink_urb(urb);
-			INIT_WORK(&anchor->clear_work_obj, wq_clear_halt);
-			schedule_work(&anchor->clear_work_obj);
+			mdev->clear_work[channel].pipe = urb->pipe;
+			schedule_work(&mdev->clear_work[channel].ws);
 			return;
 		case -ENODEV:
 		case -EPROTO:
@@ -735,6 +742,9 @@ static int hdm_configure_channel(struct most_interface *iface, int channel,
 
 	mdev = to_mdev(iface);
 	mdev->is_channel_healthy[channel] = true;
+	mdev->clear_work[channel].channel = channel;
+	mdev->clear_work[channel].mdev = mdev;
+	INIT_WORK(&mdev->clear_work[channel].ws, wq_clear_halt);
 	dev = &mdev->usb_device->dev;
 
 	if (unlikely(!iface || !conf)) {
@@ -916,33 +926,19 @@ static void wq_netinfo(struct work_struct *wq_obj)
  */
 static void wq_clear_halt(struct work_struct *wq_obj)
 {
-	struct buf_anchor *anchor;
-	struct most_dev *mdev;
-	struct mbo *mbo;
-	struct urb *urb;
-	unsigned int channel;
-	unsigned long flags;
+	struct clear_hold_work *clear_work = to_clear_hold_work(wq_obj);
+	struct most_dev *mdev = clear_work->mdev;
+	unsigned int channel = clear_work->channel;
+	int pipe = clear_work->pipe;
 
-	anchor = to_buf_anchor(wq_obj);
-	urb = anchor->urb;
-	mbo = urb->context;
-	mdev = to_mdev(mbo->ifp);
-	channel = mbo->hdm_channel_id;
-
-	if (usb_clear_halt(urb->dev, urb->pipe))
+	mutex_lock(&mdev->io_mutex);
+	free_anchored_buffers(mdev, channel, MBO_E_INVAL);
+	if (usb_clear_halt(mdev->usb_device, pipe))
 		dev_warn(&mdev->usb_device->dev, "Failed to reset endpoint.\n");
 
-	usb_free_urb(urb);
-	spin_lock_irqsave(&mdev->anchor_list_lock[channel], flags);
-	list_del(&anchor->list);
-	spin_unlock_irqrestore(&mdev->anchor_list_lock[channel], flags);
-
-	if (likely(mbo->complete))
-		mbo->complete(mbo);
 	if (mdev->conf[channel].direction & MOST_CH_TX)
 		most_resume_enqueue(&mdev->iface, channel);
-
-	kfree(anchor);
+	mutex_unlock(&mdev->io_mutex);
 }
 
 /**
-- 
1.9.1

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[PATCH 04/17] staging: most: hdm-usb: stop core from submitting buffers in case of broken pipe

[Christian Gromm]

This patch ensures that no more packets are submitted by the core in
case an USB endpoint has reported a broken pipe (-EPIPE).

Signed-off-by: Andrey Shvetsov <andrey.shvetsov@k2l.de>
Signed-off-by: Christian Gromm <christian.gromm@microchip.com>
---
 drivers/staging/most/hdm-usb/hdm_usb.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/staging/most/hdm-usb/hdm_usb.c b/drivers/staging/most/hdm-usb/hdm_usb.c
index 8f1c096..03cdd0d 100644
--- a/drivers/staging/most/hdm-usb/hdm_usb.c
+++ b/drivers/staging/most/hdm-usb/hdm_usb.c
@@ -580,6 +580,7 @@ static void hdm_read_completion(struct urb *urb)
 		switch (urb->status) {
 		case -EPIPE:
 			dev_warn(dev, "Broken IN pipe detected\n");
+			most_stop_enqueue(&mdev->iface, channel);
 			mbo->status = MBO_E_INVAL;
 			mdev->clear_work[channel].pipe = urb->pipe;
 			schedule_work(&mdev->clear_work[channel].ws);
@@ -936,8 +937,7 @@ static void wq_clear_halt(struct work_struct *wq_obj)
 	if (usb_clear_halt(mdev->usb_device, pipe))
 		dev_warn(&mdev->usb_device->dev, "Failed to reset endpoint.\n");
 
-	if (mdev->conf[channel].direction & MOST_CH_TX)
-		most_resume_enqueue(&mdev->iface, channel);
+	most_resume_enqueue(&mdev->iface, channel);
 	mutex_unlock(&mdev->io_mutex);
 }
 
-- 
1.9.1

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[PATCH 05/17] staging: most: hdm-usb: add USB product id

[Christian Gromm]

This patch adds support for the OS81119 MOST network interface controller
to the driver.

Signed-off-by: Christian Gromm <christian.gromm@microchip.com>
---
 drivers/staging/most/hdm-usb/hdm_usb.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/staging/most/hdm-usb/hdm_usb.c b/drivers/staging/most/hdm-usb/hdm_usb.c
index 03cdd0d..beb50cd 100644
--- a/drivers/staging/most/hdm-usb/hdm_usb.c
+++ b/drivers/staging/most/hdm-usb/hdm_usb.c
@@ -44,6 +44,7 @@
 #define USB_VENDOR_ID_SMSC	0x0424  /* VID: SMSC */
 #define USB_DEV_ID_BRDG		0xC001  /* PID: USB Bridge */
 #define USB_DEV_ID_INIC		0xCF18  /* PID: USB INIC */
+#define USB_DEV_ID_OS81119	0xCF19  /* PID: USB OS81119 */
 /* DRCI Addresses */
 #define DRCI_REG_NI_STATE	0x0100
 #define DRCI_REG_PACKET_BW	0x0101
@@ -954,6 +955,7 @@ static const struct file_operations hdm_usb_fops = {
 static struct usb_device_id usbid[] = {
 	{ USB_DEVICE(USB_VENDOR_ID_SMSC, USB_DEV_ID_BRDG), },
 	{ USB_DEVICE(USB_VENDOR_ID_SMSC, USB_DEV_ID_INIC), },
+	{ USB_DEVICE(USB_VENDOR_ID_SMSC, USB_DEV_ID_OS81119), },
 	{ } /* Terminating entry */
 };
 
@@ -1327,7 +1329,8 @@ hdm_probe(struct usb_interface *interface, const struct usb_device_id *id)
 	}
 
 	mutex_lock(&mdev->io_mutex);
-	if (le16_to_cpu(usb_dev->descriptor.idProduct) == USB_DEV_ID_INIC) {
+	if (le16_to_cpu(usb_dev->descriptor.idProduct) == USB_DEV_ID_INIC ||
+	    le16_to_cpu(usb_dev->descriptor.idProduct) == USB_DEV_ID_OS81119) {
 		/* this increments the reference count of the instance
 		 * object of the core
 		 */
-- 
1.9.1

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[PATCH 06/17] staging: most: hdm-usb: rename ID_INIC for consistency

[Christian Gromm]

In order to have a consistent naming convention this patch renames
USB_DEV_ID_INIC to USB_DEV_ID_OS81118.

Signed-off-by: Andrey Shvetsov <andrey.shvetsov@k2l.de>
Signed-off-by: Christian Gromm <christian.gromm@microchip.com>
---
 drivers/staging/most/hdm-usb/hdm_usb.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/staging/most/hdm-usb/hdm_usb.c b/drivers/staging/most/hdm-usb/hdm_usb.c
index beb50cd..c2ba5a1 100644
--- a/drivers/staging/most/hdm-usb/hdm_usb.c
+++ b/drivers/staging/most/hdm-usb/hdm_usb.c
@@ -43,7 +43,7 @@
 
 #define USB_VENDOR_ID_SMSC	0x0424  /* VID: SMSC */
 #define USB_DEV_ID_BRDG		0xC001  /* PID: USB Bridge */
-#define USB_DEV_ID_INIC		0xCF18  /* PID: USB INIC */
+#define USB_DEV_ID_OS81118	0xCF18  /* PID: USB OS81118 */
 #define USB_DEV_ID_OS81119	0xCF19  /* PID: USB OS81119 */
 /* DRCI Addresses */
 #define DRCI_REG_NI_STATE	0x0100
@@ -954,7 +954,7 @@ static const struct file_operations hdm_usb_fops = {
  */
 static struct usb_device_id usbid[] = {
 	{ USB_DEVICE(USB_VENDOR_ID_SMSC, USB_DEV_ID_BRDG), },
-	{ USB_DEVICE(USB_VENDOR_ID_SMSC, USB_DEV_ID_INIC), },
+	{ USB_DEVICE(USB_VENDOR_ID_SMSC, USB_DEV_ID_OS81118), },
 	{ USB_DEVICE(USB_VENDOR_ID_SMSC, USB_DEV_ID_OS81119), },
 	{ } /* Terminating entry */
 };
@@ -1329,7 +1329,7 @@ hdm_probe(struct usb_interface *interface, const struct usb_device_id *id)
 	}
 
 	mutex_lock(&mdev->io_mutex);
-	if (le16_to_cpu(usb_dev->descriptor.idProduct) == USB_DEV_ID_INIC ||
+	if (le16_to_cpu(usb_dev->descriptor.idProduct) == USB_DEV_ID_OS81118 ||
 	    le16_to_cpu(usb_dev->descriptor.idProduct) == USB_DEV_ID_OS81119) {
 		/* this increments the reference count of the instance
 		 * object of the core
-- 
1.9.1

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[PATCH 07/17] staging: most: hdm-usb: make use of is_channel_healthy flag

[Christian Gromm]

This patch makes the write completion handler use the is_channel_healthy
flag to prevent the hdm from scheduling a second clear_halt workqueue in
case an endpoint reported a STALL condition.

Signed-off-by: Christian Gromm <christian.gromm@microchip.com>
---
 drivers/staging/most/hdm-usb/hdm_usb.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/staging/most/hdm-usb/hdm_usb.c b/drivers/staging/most/hdm-usb/hdm_usb.c
index c2ba5a1..57d6c6d 100644
--- a/drivers/staging/most/hdm-usb/hdm_usb.c
+++ b/drivers/staging/most/hdm-usb/hdm_usb.c
@@ -418,6 +418,7 @@ static void hdm_write_completion(struct urb *urb)
 		case -EPIPE:
 			dev_warn(dev, "Broken OUT pipe detected\n");
 			most_stop_enqueue(&mdev->iface, channel);
+			mdev->is_channel_healthy[channel] = false;
 			mbo->status = MBO_E_INVAL;
 			mdev->clear_work[channel].pipe = urb->pipe;
 			schedule_work(&mdev->clear_work[channel].ws);
@@ -582,6 +583,7 @@ static void hdm_read_completion(struct urb *urb)
 		case -EPIPE:
 			dev_warn(dev, "Broken IN pipe detected\n");
 			most_stop_enqueue(&mdev->iface, channel);
+			mdev->is_channel_healthy[channel] = false;
 			mbo->status = MBO_E_INVAL;
 			mdev->clear_work[channel].pipe = urb->pipe;
 			schedule_work(&mdev->clear_work[channel].ws);
@@ -938,6 +940,7 @@ static void wq_clear_halt(struct work_struct *wq_obj)
 	if (usb_clear_halt(mdev->usb_device, pipe))
 		dev_warn(&mdev->usb_device->dev, "Failed to reset endpoint.\n");
 
+	mdev->is_channel_healthy[channel] = true;
 	most_resume_enqueue(&mdev->iface, channel);
 	mutex_unlock(&mdev->io_mutex);
 }
-- 
1.9.1

[PATCH 08/17] staging: most: hdm-usb: remove redundant conditions

[Christian Gromm]

This patch removes the duplication of the expression
(urb->status == -ENOENT || urb->status == -ECONNRESET).

Signed-off-by: Andrey Shvetsov <andrey.shvetsov@k2l.de>
Signed-off-by: Christian Gromm <christian.gromm@microchip.com>
---
 drivers/staging/most/hdm-usb/hdm_usb.c | 8 ++------
 1 file changed, 2 insertions(+), 6 deletions(-)

diff --git a/drivers/staging/most/hdm-usb/hdm_usb.c b/drivers/staging/most/hdm-usb/hdm_usb.c
index 57d6c6d..ddee281 100644
--- a/drivers/staging/most/hdm-usb/hdm_usb.c
+++ b/drivers/staging/most/hdm-usb/hdm_usb.c
@@ -410,9 +410,7 @@ static void hdm_write_completion(struct urb *urb)
 		return;
 	}
 
-	if (unlikely(urb->status && !(urb->status == -ENOENT ||
-				      urb->status == -ECONNRESET ||
-				      urb->status == -ESHUTDOWN))) {
+	if (unlikely(urb->status && urb->status != -ESHUTDOWN)) {
 		mbo->processed_length = 0;
 		switch (urb->status) {
 		case -EPIPE:
@@ -575,9 +573,7 @@ static void hdm_read_completion(struct urb *urb)
 		return;
 	}
 
-	if (unlikely(urb->status && !(urb->status == -ENOENT ||
-				      urb->status == -ECONNRESET ||
-				      urb->status == -ESHUTDOWN))) {
+	if (unlikely(urb->status && urb->status != -ESHUTDOWN)) {
 		mbo->processed_length = 0;
 		switch (urb->status) {
 		case -EPIPE:
-- 
1.9.1

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[PATCH 09/17] staging: most: hdm-usb: simplify initialization of mbo->status.

[Christian Gromm]

This patch simplifies the code that initializes mbo->status.

Signed-off-by: Andrey Shvetsov <andrey.shvetsov@k2l.de>
Signed-off-by: Christian Gromm <christian.gromm@microchip.com>
---
 drivers/staging/most/hdm-usb/hdm_usb.c | 14 +++++---------
 1 file changed, 5 insertions(+), 9 deletions(-)

diff --git a/drivers/staging/most/hdm-usb/hdm_usb.c b/drivers/staging/most/hdm-usb/hdm_usb.c
index ddee281..7f00aaf 100644
--- a/drivers/staging/most/hdm-usb/hdm_usb.c
+++ b/drivers/staging/most/hdm-usb/hdm_usb.c
@@ -596,15 +596,11 @@ static void hdm_read_completion(struct urb *urb)
 		}
 	} else {
 		mbo->processed_length = urb->actual_length;
-		if (!mdev->padding_active[channel]) {
-			mbo->status = MBO_SUCCESS;
-		} else {
-			if (hdm_remove_padding(mdev, channel, mbo)) {
-				mbo->processed_length = 0;
-				mbo->status = MBO_E_INVAL;
-			} else {
-				mbo->status = MBO_SUCCESS;
-			}
+		mbo->status = MBO_SUCCESS;
+		if (mdev->padding_active[channel] &&
+		    hdm_remove_padding(mdev, channel, mbo)) {
+			mbo->processed_length = 0;
+			mbo->status = MBO_E_INVAL;
 		}
 	}
 	spin_lock_irqsave(&mdev->anchor_list_lock[channel], flags);
-- 
1.9.1

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[PATCH 10/17] staging: most: hdm-usb: fix race between enqueue and most_stop_enqueue

[Christian Gromm]

The "broken in pipe" handler of the USB-HDM calls most_stop_enqueue() to
stop the MBO traffic before returning all MBOs back to the Mostcore.  As
the enqueue() call from the Mostcore may run in parallel with the
most_stop_enqueue(), the HDM may run into the inconsistent state and
crash the kernel.

This patch synchronizes enqueue(), most_stop_enqueue() and
most_resume_enqueue() with a mutex, hence avoiding the race condition.

Signed-off-by: Andrey Shvetsov <andrey.shvetsov@k2l.de>
Signed-off-by: Christian Gromm <christian.gromm@microchip.com>
---
 drivers/staging/most/hdm-usb/hdm_usb.c |  3 +-
 drivers/staging/most/mostcore/core.c   | 53 ++++++++++++++++++++++++----------
 2 files changed, 38 insertions(+), 18 deletions(-)

diff --git a/drivers/staging/most/hdm-usb/hdm_usb.c b/drivers/staging/most/hdm-usb/hdm_usb.c
index 7f00aaf..8d8c72c 100644
--- a/drivers/staging/most/hdm-usb/hdm_usb.c
+++ b/drivers/staging/most/hdm-usb/hdm_usb.c
@@ -415,7 +415,6 @@ static void hdm_write_completion(struct urb *urb)
 		switch (urb->status) {
 		case -EPIPE:
 			dev_warn(dev, "Broken OUT pipe detected\n");
-			most_stop_enqueue(&mdev->iface, channel);
 			mdev->is_channel_healthy[channel] = false;
 			mbo->status = MBO_E_INVAL;
 			mdev->clear_work[channel].pipe = urb->pipe;
@@ -578,7 +577,6 @@ static void hdm_read_completion(struct urb *urb)
 		switch (urb->status) {
 		case -EPIPE:
 			dev_warn(dev, "Broken IN pipe detected\n");
-			most_stop_enqueue(&mdev->iface, channel);
 			mdev->is_channel_healthy[channel] = false;
 			mbo->status = MBO_E_INVAL;
 			mdev->clear_work[channel].pipe = urb->pipe;
@@ -928,6 +926,7 @@ static void wq_clear_halt(struct work_struct *wq_obj)
 	int pipe = clear_work->pipe;
 
 	mutex_lock(&mdev->io_mutex);
+	most_stop_enqueue(&mdev->iface, channel);
 	free_anchored_buffers(mdev, channel, MBO_E_INVAL);
 	if (usb_clear_halt(mdev->usb_device, pipe))
 		dev_warn(&mdev->usb_device->dev, "Failed to reset endpoint.\n");
diff --git a/drivers/staging/most/mostcore/core.c b/drivers/staging/most/mostcore/core.c
index b03cdc9..db0606ca 100644
--- a/drivers/staging/most/mostcore/core.c
+++ b/drivers/staging/most/mostcore/core.c
@@ -51,6 +51,7 @@ struct most_c_obj {
 	u16 channel_id;
 	bool is_poisoned;
 	struct mutex start_mutex;
+	struct mutex nq_mutex; /* nq thread synchronization */
 	int is_starving;
 	struct most_interface *iface;
 	struct most_inst_obj *inst;
@@ -1131,18 +1132,18 @@ static inline void trash_mbo(struct mbo *mbo)
 	spin_unlock_irqrestore(&c->fifo_lock, flags);
 }
 
-static struct mbo *get_hdm_mbo(struct most_c_obj *c)
+static bool hdm_mbo_ready(struct most_c_obj *c)
 {
-	unsigned long flags;
-	struct mbo *mbo;
+	bool empty;
 
-	spin_lock_irqsave(&c->fifo_lock, flags);
-	if (c->enqueue_halt || list_empty(&c->halt_fifo))
-		mbo = NULL;
-	else
-		mbo = list_pop_mbo(&c->halt_fifo);
-	spin_unlock_irqrestore(&c->fifo_lock, flags);
-	return mbo;
+	if (c->enqueue_halt)
+		return false;
+
+	spin_lock_irq(&c->fifo_lock);
+	empty = list_empty(&c->halt_fifo);
+	spin_unlock_irq(&c->fifo_lock);
+
+	return !empty;
 }
 
 static void nq_hdm_mbo(struct mbo *mbo)
@@ -1160,20 +1161,32 @@ static int hdm_enqueue_thread(void *data)
 {
 	struct most_c_obj *c = data;
 	struct mbo *mbo;
+	int ret;
 	typeof(c->iface->enqueue) enqueue = c->iface->enqueue;
 
 	while (likely(!kthread_should_stop())) {
 		wait_event_interruptible(c->hdm_fifo_wq,
-					 (mbo = get_hdm_mbo(c)) ||
+					 hdm_mbo_ready(c) ||
 					 kthread_should_stop());
 
-		if (unlikely(!mbo))
+		mutex_lock(&c->nq_mutex);
+		spin_lock_irq(&c->fifo_lock);
+		if (unlikely(c->enqueue_halt || list_empty(&c->halt_fifo))) {
+			spin_unlock_irq(&c->fifo_lock);
+			mutex_unlock(&c->nq_mutex);
 			continue;
+		}
+
+		mbo = list_pop_mbo(&c->halt_fifo);
+		spin_unlock_irq(&c->fifo_lock);
 
 		if (c->cfg.direction == MOST_CH_RX)
 			mbo->buffer_length = c->cfg.buffer_size;
 
-		if (unlikely(enqueue(mbo->ifp, mbo->hdm_channel_id, mbo))) {
+		ret = enqueue(mbo->ifp, mbo->hdm_channel_id, mbo);
+		mutex_unlock(&c->nq_mutex);
+
+		if (unlikely(ret)) {
 			pr_err("hdm enqueue failed\n");
 			nq_hdm_mbo(mbo);
 			c->hdm_enqueue_task = NULL;
@@ -1759,6 +1772,7 @@ struct kobject *most_register_interface(struct most_interface *iface)
 		init_completion(&c->cleanup);
 		atomic_set(&c->mbo_ref, 0);
 		mutex_init(&c->start_mutex);
+		mutex_init(&c->nq_mutex);
 		list_add_tail(&c->list, &inst->channel_list);
 	}
 	pr_info("registered new MOST device mdev%d (%s)\n",
@@ -1824,8 +1838,12 @@ void most_stop_enqueue(struct most_interface *iface, int id)
 {
 	struct most_c_obj *c = get_channel_by_iface(iface, id);
 
-	if (likely(c))
-		c->enqueue_halt = true;
+	if (!c)
+		return;
+
+	mutex_lock(&c->nq_mutex);
+	c->enqueue_halt = true;
+	mutex_unlock(&c->nq_mutex);
 }
 EXPORT_SYMBOL_GPL(most_stop_enqueue);
 
@@ -1841,9 +1859,12 @@ void most_resume_enqueue(struct most_interface *iface, int id)
 {
 	struct most_c_obj *c = get_channel_by_iface(iface, id);
 
-	if (unlikely(!c))
+	if (!c)
 		return;
+
+	mutex_lock(&c->nq_mutex);
 	c->enqueue_halt = false;
+	mutex_unlock(&c->nq_mutex);
 
 	wake_up_interruptible(&c->hdm_fifo_wq);
 }
-- 
1.9.1

[PATCH 11/17] staging: most: hdm-usb: assign spinlock to local variable

[Christian Gromm]

This patch assigns the spinlock of struct mdev to local spinlock_t
variable to get rid of all the ugly dereferencing.

Signed-off-by: Andrey Shvetsov <andrey.shvetsov@k2l.de>
Signed-off-by: Christian Gromm <christian.gromm@microchip.com>
---
 drivers/staging/most/hdm-usb/hdm_usb.c | 31 +++++++++++++++++++------------
 1 file changed, 19 insertions(+), 12 deletions(-)

diff --git a/drivers/staging/most/hdm-usb/hdm_usb.c b/drivers/staging/most/hdm-usb/hdm_usb.c
index 8d8c72c..4156a30 100644
--- a/drivers/staging/most/hdm-usb/hdm_usb.c
+++ b/drivers/staging/most/hdm-usb/hdm_usb.c
@@ -206,14 +206,15 @@ static void free_anchored_buffers(struct most_dev *mdev, unsigned int channel,
 {
 	struct mbo *mbo;
 	struct buf_anchor *anchor, *tmp;
+	spinlock_t *lock = mdev->anchor_list_lock + channel; /* temp. lock */
 	unsigned long flags;
 
-	spin_lock_irqsave(&mdev->anchor_list_lock[channel], flags);
+	spin_lock_irqsave(lock, flags);
 	list_for_each_entry_safe(anchor, tmp, &mdev->anchor_list[channel],
 				 list) {
 		struct urb *urb = anchor->urb;
 
-		spin_unlock_irqrestore(&mdev->anchor_list_lock[channel], flags);
+		spin_unlock_irqrestore(lock, flags);
 		if (likely(urb)) {
 			mbo = urb->context;
 			if (!irqs_disabled()) {
@@ -229,11 +230,11 @@ static void free_anchored_buffers(struct most_dev *mdev, unsigned int channel,
 			}
 			usb_free_urb(urb);
 		}
-		spin_lock_irqsave(&mdev->anchor_list_lock[channel], flags);
+		spin_lock_irqsave(lock, flags);
 		list_del(&anchor->list);
 		kfree(anchor);
 	}
-	spin_unlock_irqrestore(&mdev->anchor_list_lock[channel], flags);
+	spin_unlock_irqrestore(lock, flags);
 }
 
 /**
@@ -397,12 +398,14 @@ static void hdm_write_completion(struct urb *urb)
 	struct device *dev;
 	unsigned int channel;
 	unsigned long flags;
+	spinlock_t *lock; /* temp. lock */
 
 	mbo = urb->context;
 	anchor = mbo->priv;
 	mdev = to_mdev(mbo->ifp);
 	channel = mbo->hdm_channel_id;
 	dev = &mdev->usb_device->dev;
+	lock = mdev->anchor_list_lock + channel;
 
 	if ((urb->status == -ENOENT) || (urb->status == -ECONNRESET) ||
 	    (!mdev->is_channel_healthy[channel])) {
@@ -433,9 +436,9 @@ static void hdm_write_completion(struct urb *urb)
 		mbo->processed_length = urb->actual_length;
 	}
 
-	spin_lock_irqsave(&mdev->anchor_list_lock[channel], flags);
+	spin_lock_irqsave(lock, flags);
 	list_del(&anchor->list);
-	spin_unlock_irqrestore(&mdev->anchor_list_lock[channel], flags);
+	spin_unlock_irqrestore(lock, flags);
 	kfree(anchor);
 
 	if (likely(mbo->complete))
@@ -559,12 +562,14 @@ static void hdm_read_completion(struct urb *urb)
 	struct device *dev;
 	unsigned long flags;
 	unsigned int channel;
+	spinlock_t *lock; /* temp. lock */
 
 	mbo = urb->context;
 	anchor = mbo->priv;
 	mdev = to_mdev(mbo->ifp);
 	channel = mbo->hdm_channel_id;
 	dev = &mdev->usb_device->dev;
+	lock = mdev->anchor_list_lock + channel;
 
 	if ((urb->status == -ENOENT) || (urb->status == -ECONNRESET) ||
 	    (!mdev->is_channel_healthy[channel])) {
@@ -601,9 +606,9 @@ static void hdm_read_completion(struct urb *urb)
 			mbo->status = MBO_E_INVAL;
 		}
 	}
-	spin_lock_irqsave(&mdev->anchor_list_lock[channel], flags);
+	spin_lock_irqsave(lock, flags);
 	list_del(&anchor->list);
-	spin_unlock_irqrestore(&mdev->anchor_list_lock[channel], flags);
+	spin_unlock_irqrestore(lock, flags);
 	kfree(anchor);
 
 	if (likely(mbo->complete))
@@ -638,6 +643,7 @@ static int hdm_enqueue(struct most_interface *iface, int channel,
 	unsigned long flags;
 	unsigned long length;
 	void *virt_address;
+	spinlock_t *lock; /* temp. lock */
 
 	if (unlikely(!iface || !mbo))
 		return -EIO;
@@ -697,9 +703,10 @@ static int hdm_enqueue(struct most_interface *iface, int channel,
 	}
 	urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
 
-	spin_lock_irqsave(&mdev->anchor_list_lock[channel], flags);
+	lock = mdev->anchor_list_lock + channel;
+	spin_lock_irqsave(lock, flags);
 	list_add_tail(&anchor->list, &mdev->anchor_list[channel]);
-	spin_unlock_irqrestore(&mdev->anchor_list_lock[channel], flags);
+	spin_unlock_irqrestore(lock, flags);
 
 	retval = usb_submit_urb(urb, GFP_KERNEL);
 	if (retval) {
@@ -709,9 +716,9 @@ static int hdm_enqueue(struct most_interface *iface, int channel,
 	return 0;
 
 _error_1:
-	spin_lock_irqsave(&mdev->anchor_list_lock[channel], flags);
+	spin_lock_irqsave(lock, flags);
 	list_del(&anchor->list);
-	spin_unlock_irqrestore(&mdev->anchor_list_lock[channel], flags);
+	spin_unlock_irqrestore(lock, flags);
 	kfree(anchor);
 _error:
 	usb_free_urb(urb);
-- 
1.9.1

_______________________________________________
devel mailing list
devel@linuxdriverproject.org
http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel

[PATCH 12/17] staging: most: hdm-usb: synchronize release of struct buf_anchor

[Christian Gromm]

In case a channel that is going to be destroyed has been tagged as not
"healthy" by the function hdm_poison_channel() while the functions
hdm_write_completion() or hdm_read_completion() are being executed, they
race for destruction of buf_anchor.

This patch fixes the problem.

Signed-off-by: Andrey Shvetsov <andrey.shvetsov@k2l.de>
Signed-off-by: Christian Gromm <christian.gromm@microchip.com>
---
 drivers/staging/most/hdm-usb/hdm_usb.c | 14 ++++++++++++--
 1 file changed, 12 insertions(+), 2 deletions(-)

diff --git a/drivers/staging/most/hdm-usb/hdm_usb.c b/drivers/staging/most/hdm-usb/hdm_usb.c
index 4156a30..26b5c1b 100644
--- a/drivers/staging/most/hdm-usb/hdm_usb.c
+++ b/drivers/staging/most/hdm-usb/hdm_usb.c
@@ -285,6 +285,8 @@ static unsigned int get_stream_frame_size(struct most_channel_config *cfg)
 static int hdm_poison_channel(struct most_interface *iface, int channel)
 {
 	struct most_dev *mdev;
+	unsigned long flags;
+	spinlock_t *lock; /* temp. lock */
 
 	mdev = to_mdev(iface);
 	if (unlikely(!iface)) {
@@ -296,7 +298,10 @@ static int hdm_poison_channel(struct most_interface *iface, int channel)
 		return -ECHRNG;
 	}
 
+	lock = mdev->anchor_list_lock + channel;
+	spin_lock_irqsave(lock, flags);
 	mdev->is_channel_healthy[channel] = false;
+	spin_unlock_irqrestore(lock, flags);
 
 	cancel_work_sync(&mdev->clear_work[channel].ws);
 
@@ -407,8 +412,10 @@ static void hdm_write_completion(struct urb *urb)
 	dev = &mdev->usb_device->dev;
 	lock = mdev->anchor_list_lock + channel;
 
+	spin_lock_irqsave(lock, flags);
 	if ((urb->status == -ENOENT) || (urb->status == -ECONNRESET) ||
 	    (!mdev->is_channel_healthy[channel])) {
+		spin_unlock_irqrestore(lock, flags);
 		complete(&anchor->urb_compl);
 		return;
 	}
@@ -419,6 +426,7 @@ static void hdm_write_completion(struct urb *urb)
 		case -EPIPE:
 			dev_warn(dev, "Broken OUT pipe detected\n");
 			mdev->is_channel_healthy[channel] = false;
+			spin_unlock_irqrestore(lock, flags);
 			mbo->status = MBO_E_INVAL;
 			mdev->clear_work[channel].pipe = urb->pipe;
 			schedule_work(&mdev->clear_work[channel].ws);
@@ -436,7 +444,6 @@ static void hdm_write_completion(struct urb *urb)
 		mbo->processed_length = urb->actual_length;
 	}
 
-	spin_lock_irqsave(lock, flags);
 	list_del(&anchor->list);
 	spin_unlock_irqrestore(lock, flags);
 	kfree(anchor);
@@ -571,8 +578,10 @@ static void hdm_read_completion(struct urb *urb)
 	dev = &mdev->usb_device->dev;
 	lock = mdev->anchor_list_lock + channel;
 
+	spin_lock_irqsave(lock, flags);
 	if ((urb->status == -ENOENT) || (urb->status == -ECONNRESET) ||
 	    (!mdev->is_channel_healthy[channel])) {
+		spin_unlock_irqrestore(lock, flags);
 		complete(&anchor->urb_compl);
 		return;
 	}
@@ -583,6 +592,7 @@ static void hdm_read_completion(struct urb *urb)
 		case -EPIPE:
 			dev_warn(dev, "Broken IN pipe detected\n");
 			mdev->is_channel_healthy[channel] = false;
+			spin_unlock_irqrestore(lock, flags);
 			mbo->status = MBO_E_INVAL;
 			mdev->clear_work[channel].pipe = urb->pipe;
 			schedule_work(&mdev->clear_work[channel].ws);
@@ -606,7 +616,7 @@ static void hdm_read_completion(struct urb *urb)
 			mbo->status = MBO_E_INVAL;
 		}
 	}
-	spin_lock_irqsave(lock, flags);
+
 	list_del(&anchor->list);
 	spin_unlock_irqrestore(lock, flags);
 	kfree(anchor);
-- 
1.9.1

[PATCH 13/17] staging: most: hdm-usb: remove completion object

[Christian Gromm]

Waiting for the urb_compl object to complete evaluates always as false.
This patch removes this unnecessary completion object.

Signed-off-by: Andrey Shvetsov <andrey.shvetsov@k2l.de>
Signed-off-by: Christian Gromm <christian.gromm@microchip.com>
---
 drivers/staging/most/hdm-usb/hdm_usb.c | 11 +----------
 1 file changed, 1 insertion(+), 10 deletions(-)

diff --git a/drivers/staging/most/hdm-usb/hdm_usb.c b/drivers/staging/most/hdm-usb/hdm_usb.c
index 26b5c1b..29e98dc 100644
--- a/drivers/staging/most/hdm-usb/hdm_usb.c
+++ b/drivers/staging/most/hdm-usb/hdm_usb.c
@@ -72,7 +72,6 @@
 struct buf_anchor {
 	struct urb *urb;
 	struct list_head list;
-	struct completion urb_compl;
 };
 
 /**
@@ -217,12 +216,7 @@ static void free_anchored_buffers(struct most_dev *mdev, unsigned int channel,
 		spin_unlock_irqrestore(lock, flags);
 		if (likely(urb)) {
 			mbo = urb->context;
-			if (!irqs_disabled()) {
-				usb_kill_urb(urb);
-			} else {
-				usb_unlink_urb(urb);
-				wait_for_completion(&anchor->urb_compl);
-			}
+			usb_kill_urb(urb);
 			if ((mbo) && (mbo->complete)) {
 				mbo->status = status;
 				mbo->processed_length = 0;
@@ -416,7 +410,6 @@ static void hdm_write_completion(struct urb *urb)
 	if ((urb->status == -ENOENT) || (urb->status == -ECONNRESET) ||
 	    (!mdev->is_channel_healthy[channel])) {
 		spin_unlock_irqrestore(lock, flags);
-		complete(&anchor->urb_compl);
 		return;
 	}
 
@@ -582,7 +575,6 @@ static void hdm_read_completion(struct urb *urb)
 	if ((urb->status == -ENOENT) || (urb->status == -ECONNRESET) ||
 	    (!mdev->is_channel_healthy[channel])) {
 		spin_unlock_irqrestore(lock, flags);
-		complete(&anchor->urb_compl);
 		return;
 	}
 
@@ -678,7 +670,6 @@ static int hdm_enqueue(struct most_interface *iface, int channel,
 	}
 
 	anchor->urb = urb;
-	init_completion(&anchor->urb_compl);
 	mbo->priv = anchor;
 
 	if ((mdev->padding_active[channel]) &&
-- 
1.9.1

[PATCH 14/17] staging: most: hdm-usb: remove redundant parenthesis

[Christian Gromm]

This patch removes unnecessary parenthesis in boolean expressions.

Signed-off-by: Andrey Shvetsov <andrey.shvetsov@k2l.de>
Signed-off-by: Christian Gromm <christian.gromm@microchip.com>
---
 drivers/staging/most/hdm-usb/hdm_usb.c | 51 +++++++++++++++++-----------------
 1 file changed, 25 insertions(+), 26 deletions(-)

diff --git a/drivers/staging/most/hdm-usb/hdm_usb.c b/drivers/staging/most/hdm-usb/hdm_usb.c
index 29e98dc..ffe1519 100644
--- a/drivers/staging/most/hdm-usb/hdm_usb.c
+++ b/drivers/staging/most/hdm-usb/hdm_usb.c
@@ -217,7 +217,7 @@ static void free_anchored_buffers(struct most_dev *mdev, unsigned int channel,
 		if (likely(urb)) {
 			mbo = urb->context;
 			usb_kill_urb(urb);
-			if ((mbo) && (mbo->complete)) {
+			if (mbo && mbo->complete) {
 				mbo->status = status;
 				mbo->processed_length = 0;
 				mbo->complete(mbo);
@@ -287,7 +287,7 @@ static int hdm_poison_channel(struct most_interface *iface, int channel)
 		dev_warn(&mdev->usb_device->dev, "Poison: Bad interface.\n");
 		return -EIO;
 	}
-	if (unlikely((channel < 0) || (channel >= iface->num_channels))) {
+	if (unlikely(channel < 0 || channel >= iface->num_channels)) {
 		dev_warn(&mdev->usb_device->dev, "Channel ID out of range.\n");
 		return -ECHRNG;
 	}
@@ -407,8 +407,8 @@ static void hdm_write_completion(struct urb *urb)
 	lock = mdev->anchor_list_lock + channel;
 
 	spin_lock_irqsave(lock, flags);
-	if ((urb->status == -ENOENT) || (urb->status == -ECONNRESET) ||
-	    (!mdev->is_channel_healthy[channel])) {
+	if (urb->status == -ENOENT || urb->status == -ECONNRESET ||
+	    !mdev->is_channel_healthy[channel]) {
 		spin_unlock_irqrestore(lock, flags);
 		return;
 	}
@@ -572,8 +572,8 @@ static void hdm_read_completion(struct urb *urb)
 	lock = mdev->anchor_list_lock + channel;
 
 	spin_lock_irqsave(lock, flags);
-	if ((urb->status == -ENOENT) || (urb->status == -ECONNRESET) ||
-	    (!mdev->is_channel_healthy[channel])) {
+	if (urb->status == -ENOENT || urb->status == -ECONNRESET ||
+	    !mdev->is_channel_healthy[channel]) {
 		spin_unlock_irqrestore(lock, flags);
 		return;
 	}
@@ -649,7 +649,7 @@ static int hdm_enqueue(struct most_interface *iface, int channel,
 
 	if (unlikely(!iface || !mbo))
 		return -EIO;
-	if (unlikely(iface->num_channels <= channel) || (channel < 0))
+	if (unlikely(iface->num_channels <= channel || channel < 0))
 		return -ECHRNG;
 
 	mdev = to_mdev(iface);
@@ -672,12 +672,11 @@ static int hdm_enqueue(struct most_interface *iface, int channel,
 	anchor->urb = urb;
 	mbo->priv = anchor;
 
-	if ((mdev->padding_active[channel]) &&
-	    (conf->direction & MOST_CH_TX))
-		if (hdm_add_padding(mdev, channel, mbo)) {
-			retval = -EIO;
-			goto _error;
-		}
+	if ((conf->direction & MOST_CH_TX) && mdev->padding_active[channel] &&
+	    hdm_add_padding(mdev, channel, mbo)) {
+		retval = -EIO;
+		goto _error;
+	}
 
 	urb->transfer_dma = mbo->bus_address;
 	virt_address = mbo->virt_address;
@@ -753,18 +752,18 @@ static int hdm_configure_channel(struct most_interface *iface, int channel,
 		dev_err(dev, "Bad interface or config pointer.\n");
 		return -EINVAL;
 	}
-	if (unlikely((channel < 0) || (channel >= iface->num_channels))) {
+	if (unlikely(channel < 0 || channel >= iface->num_channels)) {
 		dev_err(dev, "Channel ID out of range.\n");
 		return -EINVAL;
 	}
-	if ((!conf->num_buffers) || (!conf->buffer_size)) {
+	if (!conf->num_buffers || !conf->buffer_size) {
 		dev_err(dev, "Misconfig: buffer size or #buffers zero.\n");
 		return -EINVAL;
 	}
 
-	if (!(conf->data_type == MOST_CH_SYNC) &&
-	    !((conf->data_type == MOST_CH_ISOC_AVP) &&
-	      (conf->packets_per_xact != 0xFF))) {
+	if (conf->data_type != MOST_CH_SYNC &&
+	    !(conf->data_type == MOST_CH_ISOC_AVP &&
+	      conf->packets_per_xact != 0xFF)) {
 		mdev->padding_active[channel] = false;
 		goto exit;
 	}
@@ -773,7 +772,7 @@ static int hdm_configure_channel(struct most_interface *iface, int channel,
 	temp_size = conf->buffer_size;
 
 	frame_size = get_stream_frame_size(conf);
-	if ((frame_size == 0) || (frame_size > USB_MTU)) {
+	if (frame_size == 0 || frame_size > USB_MTU) {
 		dev_warn(dev, "Misconfig: frame size wrong\n");
 		return -EINVAL;
 	}
@@ -909,13 +908,13 @@ static void wq_netinfo(struct work_struct *wq_obj)
 
 	if (hdm_update_netinfo(mdev) < 0)
 		return;
-	if ((prev_link_stat != mdev->link_stat) ||
-	    (prev_hw_addr[0] != mdev->hw_addr[0]) ||
-	    (prev_hw_addr[1] != mdev->hw_addr[1]) ||
-	    (prev_hw_addr[2] != mdev->hw_addr[2]) ||
-	    (prev_hw_addr[3] != mdev->hw_addr[3]) ||
-	    (prev_hw_addr[4] != mdev->hw_addr[4]) ||
-	    (prev_hw_addr[5] != mdev->hw_addr[5]))
+	if (prev_link_stat != mdev->link_stat ||
+	    prev_hw_addr[0] != mdev->hw_addr[0] ||
+	    prev_hw_addr[1] != mdev->hw_addr[1] ||
+	    prev_hw_addr[2] != mdev->hw_addr[2] ||
+	    prev_hw_addr[3] != mdev->hw_addr[3] ||
+	    prev_hw_addr[4] != mdev->hw_addr[4] ||
+	    prev_hw_addr[5] != mdev->hw_addr[5])
 		most_deliver_netinfo(&mdev->iface, mdev->link_stat,
 				     &mdev->hw_addr[0]);
 }
-- 
1.9.1

[PATCH 15/17] staging: most: hdm-usb: init variables at declaration time

[Christian Gromm]

This patch initializes variables by the time they are declared.

Signed-off-by: Andrey Shvetsov <andrey.shvetsov@k2l.de>
Signed-off-by: Christian Gromm <christian.gromm@microchip.com>
---
 drivers/staging/most/hdm-usb/hdm_usb.c | 72 +++++++++++-----------------------
 1 file changed, 23 insertions(+), 49 deletions(-)

diff --git a/drivers/staging/most/hdm-usb/hdm_usb.c b/drivers/staging/most/hdm-usb/hdm_usb.c
index ffe1519..453b641 100644
--- a/drivers/staging/most/hdm-usb/hdm_usb.c
+++ b/drivers/staging/most/hdm-usb/hdm_usb.c
@@ -278,11 +278,10 @@ static unsigned int get_stream_frame_size(struct most_channel_config *cfg)
  */
 static int hdm_poison_channel(struct most_interface *iface, int channel)
 {
-	struct most_dev *mdev;
+	struct most_dev *mdev = to_mdev(iface);
 	unsigned long flags;
 	spinlock_t *lock; /* temp. lock */
 
-	mdev = to_mdev(iface);
 	if (unlikely(!iface)) {
 		dev_warn(&mdev->usb_device->dev, "Poison: Bad interface.\n");
 		return -EIO;
@@ -391,20 +390,13 @@ static int hdm_remove_padding(struct most_dev *mdev, int channel,
  */
 static void hdm_write_completion(struct urb *urb)
 {
-	struct mbo *mbo;
-	struct buf_anchor *anchor;
-	struct most_dev *mdev;
-	struct device *dev;
-	unsigned int channel;
+	struct mbo *mbo = urb->context;
+	struct buf_anchor *anchor = mbo->priv;
+	struct most_dev *mdev = to_mdev(mbo->ifp);
+	unsigned int channel = mbo->hdm_channel_id;
+	struct device *dev = &mdev->usb_device->dev;
+	spinlock_t *lock = mdev->anchor_list_lock + channel; /* temp. lock */
 	unsigned long flags;
-	spinlock_t *lock; /* temp. lock */
-
-	mbo = urb->context;
-	anchor = mbo->priv;
-	mdev = to_mdev(mbo->ifp);
-	channel = mbo->hdm_channel_id;
-	dev = &mdev->usb_device->dev;
-	lock = mdev->anchor_list_lock + channel;
 
 	spin_lock_irqsave(lock, flags);
 	if (urb->status == -ENOENT || urb->status == -ECONNRESET ||
@@ -556,20 +548,13 @@ static void hdm_write_completion(struct urb *urb)
  */
 static void hdm_read_completion(struct urb *urb)
 {
-	struct mbo *mbo;
-	struct buf_anchor *anchor;
-	struct most_dev *mdev;
-	struct device *dev;
+	struct mbo *mbo = urb->context;
+	struct buf_anchor *anchor = mbo->priv;
+	struct most_dev *mdev = to_mdev(mbo->ifp);
+	unsigned int channel = mbo->hdm_channel_id;
+	struct device *dev = &mdev->usb_device->dev;
+	spinlock_t *lock = mdev->anchor_list_lock + channel; /* temp. lock */
 	unsigned long flags;
-	unsigned int channel;
-	spinlock_t *lock; /* temp. lock */
-
-	mbo = urb->context;
-	anchor = mbo->priv;
-	mdev = to_mdev(mbo->ifp);
-	channel = mbo->hdm_channel_id;
-	dev = &mdev->usb_device->dev;
-	lock = mdev->anchor_list_lock + channel;
 
 	spin_lock_irqsave(lock, flags);
 	if (urb->status == -ENOENT || urb->status == -ECONNRESET ||
@@ -738,15 +723,13 @@ static int hdm_configure_channel(struct most_interface *iface, int channel,
 	unsigned int frame_size;
 	unsigned int temp_size;
 	unsigned int tail_space;
-	struct most_dev *mdev;
-	struct device *dev;
+	struct most_dev *mdev = to_mdev(iface);
+	struct device *dev = &mdev->usb_device->dev;
 
-	mdev = to_mdev(iface);
 	mdev->is_channel_healthy[channel] = true;
 	mdev->clear_work[channel].channel = channel;
 	mdev->clear_work[channel].mdev = mdev;
 	INIT_WORK(&mdev->clear_work[channel].ws, wq_clear_halt);
-	dev = &mdev->usb_device->dev;
 
 	if (unlikely(!iface || !conf)) {
 		dev_err(dev, "Bad interface or config pointer.\n");
@@ -896,13 +879,10 @@ static void link_stat_timer_handler(unsigned long data)
  */
 static void wq_netinfo(struct work_struct *wq_obj)
 {
-	struct most_dev *mdev;
-	int i, prev_link_stat;
+	struct most_dev *mdev = to_mdev_from_work(wq_obj);
+	int i, prev_link_stat = mdev->link_stat;
 	u8 prev_hw_addr[6];
 
-	mdev = to_mdev_from_work(wq_obj);
-	prev_link_stat = mdev->link_stat;
-
 	for (i = 0; i < 6; i++)
 		prev_hw_addr[i] = mdev->hw_addr[i];
 
@@ -1174,10 +1154,9 @@ static struct kobj_type most_dci_ktype = {
 static struct
 most_dci_obj *create_most_dci_obj(struct kobject *parent)
 {
-	struct most_dci_obj *most_dci;
+	struct most_dci_obj *most_dci = kzalloc(sizeof(*most_dci), GFP_KERNEL);
 	int retval;
 
-	most_dci = kzalloc(sizeof(*most_dci), GFP_KERNEL);
 	if (!most_dci)
 		return NULL;
 
@@ -1214,21 +1193,17 @@ static void destroy_most_dci_obj(struct most_dci_obj *p)
 static int
 hdm_probe(struct usb_interface *interface, const struct usb_device_id *id)
 {
+	struct usb_host_interface *usb_iface_desc = interface->cur_altsetting;
+	struct usb_device *usb_dev = interface_to_usbdev(interface);
+	struct device *dev = &usb_dev->dev;
+	struct most_dev *mdev = kzalloc(sizeof(*mdev), GFP_KERNEL);
 	unsigned int i;
 	unsigned int num_endpoints;
 	struct most_channel_capability *tmp_cap;
-	struct most_dev *mdev;
-	struct usb_device *usb_dev;
-	struct device *dev;
-	struct usb_host_interface *usb_iface_desc;
 	struct usb_endpoint_descriptor *ep_desc;
 	int ret = 0;
 	int err;
 
-	usb_iface_desc = interface->cur_altsetting;
-	usb_dev = interface_to_usbdev(interface);
-	dev = &usb_dev->dev;
-	mdev = kzalloc(sizeof(*mdev), GFP_KERNEL);
 	if (!mdev)
 		goto exit_ENOMEM;
 
@@ -1378,9 +1353,8 @@ exit_ENOMEM:
  */
 static void hdm_disconnect(struct usb_interface *interface)
 {
-	struct most_dev *mdev;
+	struct most_dev *mdev = usb_get_intfdata(interface);
 
-	mdev = usb_get_intfdata(interface);
 	mutex_lock(&mdev->io_mutex);
 	usb_set_intfdata(interface, NULL);
 	mdev->usb_device = NULL;
-- 
1.9.1

[PATCH 16/17] staging: most: hdm-usb: remove unnecessary status assignment

[Christian Gromm]

The USB completion callbacks set the status field of an MBO object before
scheduling the clear_work. This patch removes this redundant assignment as
the work_struct does the same for all MBOs.

Signed-off-by: Andrey Shvetsov <andrey.shvetsov@k2l.de>
Signed-off-by: Christian Gromm <christian.gromm@microchip.com>
---
 drivers/staging/most/hdm-usb/hdm_usb.c | 2 --
 1 file changed, 2 deletions(-)

diff --git a/drivers/staging/most/hdm-usb/hdm_usb.c b/drivers/staging/most/hdm-usb/hdm_usb.c
index 453b641..f44f27e 100644
--- a/drivers/staging/most/hdm-usb/hdm_usb.c
+++ b/drivers/staging/most/hdm-usb/hdm_usb.c
@@ -412,7 +412,6 @@ static void hdm_write_completion(struct urb *urb)
 			dev_warn(dev, "Broken OUT pipe detected\n");
 			mdev->is_channel_healthy[channel] = false;
 			spin_unlock_irqrestore(lock, flags);
-			mbo->status = MBO_E_INVAL;
 			mdev->clear_work[channel].pipe = urb->pipe;
 			schedule_work(&mdev->clear_work[channel].ws);
 			return;
@@ -570,7 +569,6 @@ static void hdm_read_completion(struct urb *urb)
 			dev_warn(dev, "Broken IN pipe detected\n");
 			mdev->is_channel_healthy[channel] = false;
 			spin_unlock_irqrestore(lock, flags);
-			mbo->status = MBO_E_INVAL;
 			mdev->clear_work[channel].pipe = urb->pipe;
 			schedule_work(&mdev->clear_work[channel].ws);
 			return;
-- 
1.9.1

[PATCH 17/17] staging: most: hdm-usb: add support for new USB gadget

[Christian Gromm]

This patch is needed to make the driver support Microchip's OS81210 USB
MOST network interface controller. It simply adds the gadget's product
ID to the driver's ID table.

Signed-off-by: Christian Gromm <christian.gromm@microchip.com>
---
 drivers/staging/most/hdm-usb/hdm_usb.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/staging/most/hdm-usb/hdm_usb.c b/drivers/staging/most/hdm-usb/hdm_usb.c
index f44f27e..08c4a3b 100644
--- a/drivers/staging/most/hdm-usb/hdm_usb.c
+++ b/drivers/staging/most/hdm-usb/hdm_usb.c
@@ -45,6 +45,7 @@
 #define USB_DEV_ID_BRDG		0xC001  /* PID: USB Bridge */
 #define USB_DEV_ID_OS81118	0xCF18  /* PID: USB OS81118 */
 #define USB_DEV_ID_OS81119	0xCF19  /* PID: USB OS81119 */
+#define USB_DEV_ID_OS81210	0xCF30  /* PID: USB OS81210 */
 /* DRCI Addresses */
 #define DRCI_REG_NI_STATE	0x0100
 #define DRCI_REG_PACKET_BW	0x0101
@@ -935,6 +936,7 @@ static struct usb_device_id usbid[] = {
 	{ USB_DEVICE(USB_VENDOR_ID_SMSC, USB_DEV_ID_BRDG), },
 	{ USB_DEVICE(USB_VENDOR_ID_SMSC, USB_DEV_ID_OS81118), },
 	{ USB_DEVICE(USB_VENDOR_ID_SMSC, USB_DEV_ID_OS81119), },
+	{ USB_DEVICE(USB_VENDOR_ID_SMSC, USB_DEV_ID_OS81210), },
 	{ } /* Terminating entry */
 };
 
@@ -1304,7 +1306,8 @@ hdm_probe(struct usb_interface *interface, const struct usb_device_id *id)
 
 	mutex_lock(&mdev->io_mutex);
 	if (le16_to_cpu(usb_dev->descriptor.idProduct) == USB_DEV_ID_OS81118 ||
-	    le16_to_cpu(usb_dev->descriptor.idProduct) == USB_DEV_ID_OS81119) {
+	    le16_to_cpu(usb_dev->descriptor.idProduct) == USB_DEV_ID_OS81119 ||
+	    le16_to_cpu(usb_dev->descriptor.idProduct) == USB_DEV_ID_OS81210) {
 		/* this increments the reference count of the instance
 		 * object of the core
 		 */
-- 
1.9.1