staging: comedi: addi_apci_3120: introduce struct apci3120_dmabuf

For aesthetics, wrap the DMA buffer information in a struct.
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/addi-data/hwdrv_apci3120.c

@@ -1003,6 +1003,8 @@ static int apci3120_cyclic_ai(int mode,
 		}
 	} else {
 		/* If DMA Enabled */
+		struct apci3120_dmabuf *dmabuf0 = &devpriv->dmabuf[0];
+		struct apci3120_dmabuf *dmabuf1 = &devpriv->dmabuf[1];
 		unsigned int scan_bytes = cmd->scan_end_arg * sizeof(short);
 
 		devpriv->b_InterruptMode = APCI3120_DMA_MODE;
@@ -1014,8 +1016,8 @@ static int apci3120_cyclic_ai(int mode,
 		outb(devpriv->b_ModeSelectRegister,
 			dev->iobase + APCI3120_WRITE_MODE_SELECT);
 
-		dmalen0 = devpriv->ui_DmaBufferSize[0];
-		dmalen1 = devpriv->ui_DmaBufferSize[1];
+		dmalen0 = dmabuf0->size;
+		dmalen1 = dmabuf1->size;
 
 		if (cmd->stop_src == TRIG_COUNT) {
 			/*
@@ -1050,8 +1052,8 @@ static int apci3120_cyclic_ai(int mode,
 			if (dmalen1 > s->async->prealloc_bufsz)
 				dmalen1 = s->async->prealloc_bufsz;
 		}
-		devpriv->ui_DmaBufferUsesize[0] = dmalen0;
-		devpriv->ui_DmaBufferUsesize[1] = dmalen1;
+		dmabuf0->use_size = dmalen0;
+		dmabuf1->use_size = dmalen1;
 
 		/* Initialize DMA */
 
@@ -1094,13 +1096,11 @@ static int apci3120_cyclic_ai(int mode,
 
 		/*  DMA Start Address Low */
 		outw(APCI3120_ADD_ON_MWAR_LOW, devpriv->i_IobaseAddon + 0);
-		outw((devpriv->ul_DmaBufferHw[0] & 0xFFFF),
-			devpriv->i_IobaseAddon + 2);
+		outw(dmabuf0->hw & 0xffff, devpriv->i_IobaseAddon + 2);
 
 		/* DMA Start Address High */
 		outw(APCI3120_ADD_ON_MWAR_HIGH, devpriv->i_IobaseAddon + 0);
-		outw((devpriv->ul_DmaBufferHw[0] / 65536),
-			devpriv->i_IobaseAddon + 2);
+		outw((dmabuf0->hw >> 16) & 0xffff, devpriv->i_IobaseAddon + 2);
 
 		/*
 		 * 4
@@ -1110,12 +1110,11 @@ static int apci3120_cyclic_ai(int mode,
 
 		/* Nbr of acquisition LOW */
 		outw(APCI3120_ADD_ON_MWTC_LOW, devpriv->i_IobaseAddon + 0);
-		outw((devpriv->ui_DmaBufferUsesize[0] & 0xFFFF),
-			devpriv->i_IobaseAddon + 2);
+		outw(dmabuf0->use_size & 0xffff, devpriv->i_IobaseAddon + 2);
 
 		/* Nbr of acquisition HIGH */
 		outw(APCI3120_ADD_ON_MWTC_HIGH, devpriv->i_IobaseAddon + 0);
-		outw((devpriv->ui_DmaBufferUsesize[0] / 65536),
+		outw((dmabuf0->use_size >> 16) & 0xffff,
 		     devpriv->i_IobaseAddon + 2);
 
 		/*
@@ -1248,18 +1247,17 @@ static void apci3120_interrupt_dma(int irq, void *d)
 	struct apci3120_private *devpriv = dev->private;
 	struct comedi_subdevice *s = dev->read_subdev;
 	struct comedi_cmd *cmd = &s->async->cmd;
-	unsigned int next_dma_buf, samplesinbuf;
-	unsigned long low_word, high_word, var;
+	struct apci3120_dmabuf *dmabuf;
+	unsigned int samplesinbuf;
 	unsigned int ui_Tmp;
 
-	samplesinbuf =
-		devpriv->ui_DmaBufferUsesize[devpriv->ui_DmaActualBuffer] -
+	dmabuf = &devpriv->dmabuf[devpriv->ui_DmaActualBuffer];
+
+	samplesinbuf = dmabuf->use_size -
 		       inl(devpriv->i_IobaseAmcc + AMCC_OP_REG_MWTC);
 
-	if (samplesinbuf <
-		devpriv->ui_DmaBufferUsesize[devpriv->ui_DmaActualBuffer]) {
+	if (samplesinbuf < dmabuf->use_size)
 		dev_err(dev->class_dev, "Interrupted DMA transfer!\n");
-	}
 	if (samplesinbuf & 1) {
 		dev_err(dev->class_dev, "Odd count of bytes in DMA ring!\n");
 		apci3120_cancel(dev, s);
@@ -1268,7 +1266,9 @@ static void apci3120_interrupt_dma(int irq, void *d)
 	samplesinbuf = samplesinbuf >> 1;	/*  number of received samples */
 	if (devpriv->b_DmaDoubleBuffer) {
 		/*  switch DMA buffers if is used double buffering */
-		next_dma_buf = 1 - devpriv->ui_DmaActualBuffer;
+		struct apci3120_dmabuf *next_dmabuf;
+
+		next_dmabuf = &devpriv->dmabuf[1 - devpriv->ui_DmaActualBuffer];
 
 		ui_Tmp = AGCSTS_TC_ENABLE | AGCSTS_RESET_A2P_FIFO;
 		outl(ui_Tmp, devpriv->i_IobaseAddon + AMCC_OP_REG_AGCSTS);
@@ -1280,31 +1280,24 @@ static void apci3120_interrupt_dma(int irq, void *d)
 		outw(APCI3120_ADD_ON_AGCSTS_HIGH, devpriv->i_IobaseAddon + 0);
 		outw(APCI3120_ENABLE_TRANSFER_ADD_ON_HIGH, devpriv->i_IobaseAddon + 2);	/*  0x1000 is out putted in windows driver */
 
-		var = devpriv->ul_DmaBufferHw[next_dma_buf];
-		low_word = var & 0xffff;
-		var = devpriv->ul_DmaBufferHw[next_dma_buf];
-		high_word = var / 65536;
-
 		/* DMA Start Address Low */
 		outw(APCI3120_ADD_ON_MWAR_LOW, devpriv->i_IobaseAddon + 0);
-		outw(low_word, devpriv->i_IobaseAddon + 2);
+		outw(next_dmabuf->hw & 0xffff, devpriv->i_IobaseAddon + 2);
 
 		/* DMA Start Address High */
 		outw(APCI3120_ADD_ON_MWAR_HIGH, devpriv->i_IobaseAddon + 0);
-		outw(high_word, devpriv->i_IobaseAddon + 2);
-
-		var = devpriv->ui_DmaBufferUsesize[next_dma_buf];
-		low_word = var & 0xffff;
-		var = devpriv->ui_DmaBufferUsesize[next_dma_buf];
-		high_word = var / 65536;
+		outw((next_dmabuf->hw >> 16) & 0xffff,
+		     devpriv->i_IobaseAddon + 2);
 
 		/* Nbr of acquisition LOW */
 		outw(APCI3120_ADD_ON_MWTC_LOW, devpriv->i_IobaseAddon + 0);
-		outw(low_word, devpriv->i_IobaseAddon + 2);
+		outw(next_dmabuf->use_size & 0xffff,
+		     devpriv->i_IobaseAddon + 2);
 
 		/* Nbr of acquisition HIGH */
 		outw(APCI3120_ADD_ON_MWTC_HIGH, devpriv->i_IobaseAddon + 0);
-		outw(high_word, devpriv->i_IobaseAddon + 2);
+		outw((next_dmabuf->use_size > 16) & 0xffff,
+		     devpriv->i_IobaseAddon + 2);
 
 		/*
 		 * To configure A2P FIFO
@@ -1319,9 +1312,8 @@ static void apci3120_interrupt_dma(int irq, void *d)
 
 	}
 	if (samplesinbuf) {
-		v_APCI3120_InterruptDmaMoveBlock16bit(dev, s,
-			devpriv->ul_DmaBufferVirtual[devpriv->
-				ui_DmaActualBuffer], samplesinbuf);
+		v_APCI3120_InterruptDmaMoveBlock16bit(dev, s, dmabuf->virt,
+						      samplesinbuf);
 
 		if (!(cmd->flags & CMDF_WAKE_EOS))
 			s->async->events |= COMEDI_CB_EOS;
@@ -1356,23 +1348,16 @@ static void apci3120_interrupt_dma(int irq, void *d)
 		outl(APCI3120_A2P_FIFO_MANAGEMENT,
 			devpriv->i_IobaseAmcc + AMCC_OP_REG_MCSR);
 
-		var = devpriv->ul_DmaBufferHw[0];
-		low_word = var & 0xffff;
-		var = devpriv->ul_DmaBufferHw[0];
-		high_word = var / 65536;
 		outw(APCI3120_ADD_ON_MWAR_LOW, devpriv->i_IobaseAddon + 0);
-		outw(low_word, devpriv->i_IobaseAddon + 2);
+		outw(dmabuf->hw & 0xffff, devpriv->i_IobaseAddon + 2);
 		outw(APCI3120_ADD_ON_MWAR_HIGH, devpriv->i_IobaseAddon + 0);
-		outw(high_word, devpriv->i_IobaseAddon + 2);
+		outw((dmabuf->hw >> 16) & 0xffff, devpriv->i_IobaseAddon + 2);
 
-		var = devpriv->ui_DmaBufferUsesize[0];
-		low_word = var & 0xffff;	/* changed */
-		var = devpriv->ui_DmaBufferUsesize[0];
-		high_word = var / 65536;
 		outw(APCI3120_ADD_ON_MWTC_LOW, devpriv->i_IobaseAddon + 0);
-		outw(low_word, devpriv->i_IobaseAddon + 2);
+		outw(dmabuf->use_size & 0xffff, devpriv->i_IobaseAddon + 2);
 		outw(APCI3120_ADD_ON_MWTC_HIGH, devpriv->i_IobaseAddon + 0);
-		outw(high_word, devpriv->i_IobaseAddon + 2);
+		outw((dmabuf->use_size >> 16) & 0xffff,
+		     devpriv->i_IobaseAddon + 2);
 
 		/*
 		 * To configure A2P FIFO

drivers/staging/comedi/drivers/addi_apci_3120.c

@@ -29,6 +29,13 @@ static const struct apci3120_board apci3120_boardtypes[] = {
 	},
 };
 
+struct apci3120_dmabuf {
+	unsigned short *virt;
+	dma_addr_t hw;
+	unsigned int size;
+	unsigned int use_size;
+};
+
 struct apci3120_private {
 	int iobase;
 	int i_IobaseAmcc;
@@ -41,10 +48,7 @@ struct apci3120_private {
 	unsigned short us_UseDma;
 	unsigned char b_DmaDoubleBuffer;
 	unsigned int ui_DmaActualBuffer;
-	unsigned short *ul_DmaBufferVirtual[2];
-	dma_addr_t ul_DmaBufferHw[2];
-	unsigned int ui_DmaBufferSize[2];
-	unsigned int ui_DmaBufferUsesize[2];
+	struct apci3120_dmabuf dmabuf[2];
 	unsigned char b_DigitalOutputRegister;
 	unsigned char b_TimerSelectMode;
 	unsigned char b_ModeSelectRegister;
@@ -64,22 +68,23 @@ struct apci3120_private {
 static void apci3120_dma_alloc(struct comedi_device *dev)
 {
 	struct apci3120_private *devpriv = dev->private;
+	struct apci3120_dmabuf *dmabuf;
 	int order;
 	int i;
 
 	for (i = 0; i < 2; i++) {
+		dmabuf = &devpriv->dmabuf[i];
 		for (order = 2; order >= 0; order--) {
-			devpriv->ul_DmaBufferVirtual[i] =
-			    dma_alloc_coherent(dev->hw_dev, PAGE_SIZE << order,
-					       &devpriv->ul_DmaBufferHw[i],
+			dmabuf->virt = dma_alloc_coherent(dev->hw_dev,
+							  PAGE_SIZE << order,
+							  &dmabuf->hw,
 							  GFP_KERNEL);
-
-			if (devpriv->ul_DmaBufferVirtual[i])
+			if (dmabuf->virt)
 				break;
 		}
-		if (!devpriv->ul_DmaBufferVirtual[i])
+		if (!dmabuf->virt)
 			break;
-		devpriv->ui_DmaBufferSize[i] = PAGE_SIZE << order;
+		dmabuf->size = PAGE_SIZE << order;
 
 		if (i == 0)
 			devpriv->us_UseDma = 1;
@@ -91,17 +96,17 @@ static void apci3120_dma_alloc(struct comedi_device *dev)
 static void apci3120_dma_free(struct comedi_device *dev)
 {
 	struct apci3120_private *devpriv = dev->private;
+	struct apci3120_dmabuf *dmabuf;
 	int i;
 
 	if (!devpriv)
 		return;
 
 	for (i = 0; i < 2; i++) {
-		if (devpriv->ul_DmaBufferVirtual[i]) {
-			dma_free_coherent(dev->hw_dev,
-					  devpriv->ui_DmaBufferSize[i],
-					  devpriv->ul_DmaBufferVirtual[i],
-					  devpriv->ul_DmaBufferHw[i]);
+		dmabuf = &devpriv->dmabuf[i];
+		if (dmabuf->virt) {
+			dma_free_coherent(dev->hw_dev, dmabuf->size,
+					  dmabuf->virt, dmabuf->hw);
 		}
 	}
 }