From f7d005c33c109ef034c9480334d3d25d91aa2d6d Mon Sep 17 00:00:00 2001
From: H Hartley Sweeten <hsweeten@visionengravers.com>
Date: Thu, 21 Apr 2016 12:04:44 -0700
Subject: [PATCH] staging: comedi: mite: make mite_ack_linkc() handle
 mite_sync_dma()

The mite dma is always synced on a LINKC status. Some of the mite users
sync the dma regadless of the status.

Add a 'sync' parameter to mite_ack_linkc() to force a dma sync. Then do
the dma sync as needed.

Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Reviewed-by: Ian Abbott <abbotti@mev.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/staging/comedi/drivers/mite.c         | 10 ++++++--
 drivers/staging/comedi/drivers/mite.h         |  4 ++--
 .../staging/comedi/drivers/ni_mio_common.c    | 23 +++++--------------
 drivers/staging/comedi/drivers/ni_pcidio.c    |  9 ++------
 drivers/staging/comedi/drivers/ni_tiocmd.c    |  6 ++---
 5 files changed, 20 insertions(+), 32 deletions(-)

diff --git a/drivers/staging/comedi/drivers/mite.c b/drivers/staging/comedi/drivers/mite.c
index d97059217825..b8cf89887006 100644
--- a/drivers/staging/comedi/drivers/mite.c
+++ b/drivers/staging/comedi/drivers/mite.c
@@ -779,15 +779,21 @@ static unsigned int mite_get_status(struct mite_channel *mite_chan)
 }
 
 unsigned int mite_ack_linkc(struct mite_channel *mite_chan,
-			    struct comedi_subdevice *s)
+			    struct comedi_subdevice *s,
+			    bool sync)
 {
 	struct mite_struct *mite = mite_chan->mite;
 	unsigned int status;
 
 	status = mite_get_status(mite_chan);
-	if (status & CHSR_LINKC)
+	if (status & CHSR_LINKC) {
 		writel(CHOR_CLRLC,
 		       mite->mite_io_addr + MITE_CHOR(mite_chan->channel));
+		sync = true;
+	}
+	if (sync)
+		mite_sync_dma(mite_chan, s);
+
 	if (status & CHSR_XFERR) {
 		dev_err(s->device->class_dev,
 			"mite: transfer error %08x\n", status);
diff --git a/drivers/staging/comedi/drivers/mite.h b/drivers/staging/comedi/drivers/mite.h
index f8364edf8ce8..bf6128abc464 100644
--- a/drivers/staging/comedi/drivers/mite.h
+++ b/drivers/staging/comedi/drivers/mite.h
@@ -93,8 +93,8 @@ void mite_dma_arm(struct mite_channel *mite_chan);
 void mite_dma_disarm(struct mite_channel *mite_chan);
 void mite_sync_dma(struct mite_channel *mite_chan, struct comedi_subdevice *s);
 u32 mite_bytes_in_transit(struct mite_channel *mite_chan);
-unsigned int mite_ack_linkc(struct mite_channel *mite_chan,
-			    struct comedi_subdevice *s);
+unsigned int mite_ack_linkc(struct mite_channel *, struct comedi_subdevice *,
+			    bool sync);
 int mite_done(struct mite_channel *mite_chan);
 
 void mite_prep_dma(struct mite_channel *mite_chan,
diff --git a/drivers/staging/comedi/drivers/ni_mio_common.c b/drivers/staging/comedi/drivers/ni_mio_common.c
index a3b93c1adf34..dc024f27cc48 100644
--- a/drivers/staging/comedi/drivers/ni_mio_common.c
+++ b/drivers/staging/comedi/drivers/ni_mio_common.c
@@ -3632,10 +3632,8 @@ static void handle_cdio_interrupt(struct comedi_device *dev)
 	unsigned long flags;
 
 	spin_lock_irqsave(&devpriv->mite_channel_lock, flags);
-	if (devpriv->cdo_mite_chan) {
-		mite_ack_linkc(devpriv->cdo_mite_chan, s);
-		mite_sync_dma(devpriv->cdo_mite_chan, s);
-	}
+	if (devpriv->cdo_mite_chan)
+		mite_ack_linkc(devpriv->cdo_mite_chan, s, true);
 	spin_unlock_irqrestore(&devpriv->mite_channel_lock, flags);
 
 	cdio_status = ni_readl(dev, NI_M_CDIO_STATUS_REG);
@@ -5150,21 +5148,12 @@ static irqreturn_t ni_E_interrupt(int irq, void *d)
 #ifdef PCIDMA
 	if (devpriv->mite) {
 		unsigned long flags_too;
-		unsigned int m_status;
 
 		spin_lock_irqsave(&devpriv->mite_channel_lock, flags_too);
-		if (s_ai && devpriv->ai_mite_chan) {
-			m_status = mite_ack_linkc(devpriv->ai_mite_chan, s_ai);
-			if (m_status & CHSR_LINKC)
-				mite_sync_dma(devpriv->ai_mite_chan, s_ai);
-		}
-
-		if (s_ao && devpriv->ao_mite_chan) {
-			m_status = mite_ack_linkc(devpriv->ao_mite_chan, s_ao);
-			if (m_status & CHSR_LINKC)
-				mite_sync_dma(devpriv->ao_mite_chan, s_ao);
-		}
-
+		if (s_ai && devpriv->ai_mite_chan)
+			mite_ack_linkc(devpriv->ai_mite_chan, s_ai, false);
+		if (s_ao && devpriv->ao_mite_chan)
+			mite_ack_linkc(devpriv->ao_mite_chan, s_ao, false);
 		spin_unlock_irqrestore(&devpriv->mite_channel_lock, flags_too);
 	}
 #endif
diff --git a/drivers/staging/comedi/drivers/ni_pcidio.c b/drivers/staging/comedi/drivers/ni_pcidio.c
index b4c6bab57a26..4a34da5140e0 100644
--- a/drivers/staging/comedi/drivers/ni_pcidio.c
+++ b/drivers/staging/comedi/drivers/ni_pcidio.c
@@ -400,13 +400,8 @@ static irqreturn_t nidio_interrupt(int irq, void *d)
 
 	spin_lock(&devpriv->mite_channel_lock);
 	if (devpriv->di_mite_chan) {
-		unsigned int m_status = mite_ack_linkc(devpriv->di_mite_chan,
-						       s);
-
-		if (m_status & CHSR_LINKC) {
-			mite_sync_dma(devpriv->di_mite_chan, s);
-			/* XXX need to byteswap */
-		}
+		mite_ack_linkc(devpriv->di_mite_chan, s, false);
+		/* XXX need to byteswap sync'ed dma */
 	}
 	spin_unlock(&devpriv->mite_channel_lock);
 
diff --git a/drivers/staging/comedi/drivers/ni_tiocmd.c b/drivers/staging/comedi/drivers/ni_tiocmd.c
index 5228b9fc2a72..9007c57544bf 100644
--- a/drivers/staging/comedi/drivers/ni_tiocmd.c
+++ b/drivers/staging/comedi/drivers/ni_tiocmd.c
@@ -428,10 +428,8 @@ void ni_tio_handle_interrupt(struct ni_gpct *counter,
 		break;
 	}
 	spin_lock_irqsave(&counter->lock, flags);
-	if (counter->mite_chan) {
-		mite_ack_linkc(counter->mite_chan, s);
-		mite_sync_dma(counter->mite_chan, s);
-	}
+	if (counter->mite_chan)
+		mite_ack_linkc(counter->mite_chan, s, true);
 	spin_unlock_irqrestore(&counter->lock, flags);
 }
 EXPORT_SYMBOL_GPL(ni_tio_handle_interrupt);