From fbfd9c8a1782f33d7b67294b2a42587063e61c0c Mon Sep 17 00:00:00 2001 From: Ian Abbott Date: Fri, 12 Sep 2014 12:19:56 +0100 Subject: [PATCH] staging: comedi: addi_apci_3120: use dma_alloc_coherent() Use `dma_alloc_coherent()` to allocate the DMA buffers instead of using `__get_free_pages()` to allocate and `virt_to_bus()` to get the hardware address. The coherent buffers are fairly small - at most 4 pages (although there are two of them). Use of `virt_to_bus()` is discouraged. Note: `struct addi_private` is used by some other ADDI-DATA drivers as well, but this is the only one using the affected members. Signed-off-by: Ian Abbott Reviewed-by: H Hartley Sweeten Signed-off-by: Greg Kroah-Hartman --- drivers/staging/comedi/Kconfig | 2 +- .../comedi/drivers/addi-data/addi_common.h | 3 +-- .../staging/comedi/drivers/addi_apci_3120.c | 26 +++++++++---------- 3 files changed, 15 insertions(+), 16 deletions(-) diff --git a/drivers/staging/comedi/Kconfig b/drivers/staging/comedi/Kconfig index 9eaffd4df154..06826f46929a 100644 --- a/drivers/staging/comedi/Kconfig +++ b/drivers/staging/comedi/Kconfig @@ -677,7 +677,7 @@ config COMEDI_ADDI_APCI_2200 config COMEDI_ADDI_APCI_3120 tristate "ADDI-DATA APCI_3120/3001 support" - depends on VIRT_TO_BUS + depends on HAS_DMA select COMEDI_FC ---help--- Enable support for ADDI-DATA APCI_3120/3001 cards diff --git a/drivers/staging/comedi/drivers/addi-data/addi_common.h b/drivers/staging/comedi/drivers/addi-data/addi_common.h index 88295e40eb6a..e2a3ffeee5cf 100644 --- a/drivers/staging/comedi/drivers/addi-data/addi_common.h +++ b/drivers/staging/comedi/drivers/addi-data/addi_common.h @@ -107,10 +107,9 @@ struct addi_private { unsigned char b_DmaDoubleBuffer; /* we can use double buffering */ unsigned int ui_DmaActualBuffer; /* which buffer is used now */ unsigned short *ul_DmaBufferVirtual[2]; /* pointers to DMA buffer */ - unsigned int ul_DmaBufferHw[2]; /* hw address of DMA buff */ + dma_addr_t ul_DmaBufferHw[2]; /* hw address of DMA buff */ unsigned int ui_DmaBufferSize[2]; /* size of dma buffer in bytes */ unsigned int ui_DmaBufferUsesize[2]; /* which size we may now used for transfer */ - unsigned int ui_DmaBufferPageOrder[2]; /* log2 of pages in buffer */ unsigned char b_DigitalOutputRegister; /* Digital Output Register */ unsigned char b_OutputMemoryStatus; unsigned char b_TimerSelectMode; /* Contain data written at iobase + 0C */ diff --git a/drivers/staging/comedi/drivers/addi_apci_3120.c b/drivers/staging/comedi/drivers/addi_apci_3120.c index 57c36ed9588c..1025541fb4a3 100644 --- a/drivers/staging/comedi/drivers/addi_apci_3120.c +++ b/drivers/staging/comedi/drivers/addi_apci_3120.c @@ -95,17 +95,16 @@ static int apci3120_auto_attach(struct comedi_device *dev, for (i = 0; i < 2; i++) { for (order = 2; order >= 0; order--) { devpriv->ul_DmaBufferVirtual[i] = - (void *)__get_free_pages(GFP_KERNEL, order); + dma_alloc_coherent(dev->hw_dev, PAGE_SIZE << order, + &devpriv->ul_DmaBufferHw[i], + GFP_KERNEL); if (devpriv->ul_DmaBufferVirtual[i]) break; } if (!devpriv->ul_DmaBufferVirtual[i]) break; - devpriv->ui_DmaBufferPageOrder[i] = order; devpriv->ui_DmaBufferSize[i] = PAGE_SIZE << order; - devpriv->ul_DmaBufferHw[i] = - virt_to_bus(devpriv->ul_DmaBufferVirtual[i]); } if (!devpriv->ul_DmaBufferVirtual[0]) devpriv->us_UseDma = 0; @@ -198,15 +197,16 @@ static void apci3120_detach(struct comedi_device *dev) apci3120_reset(dev); comedi_pci_detach(dev); if (devpriv) { - if (devpriv->ul_DmaBufferVirtual[0]) { - free_pages((unsigned long)devpriv-> - ul_DmaBufferVirtual[0], - devpriv->ui_DmaBufferPageOrder[0]); - } - if (devpriv->ul_DmaBufferVirtual[1]) { - free_pages((unsigned long)devpriv-> - ul_DmaBufferVirtual[1], - devpriv->ui_DmaBufferPageOrder[1]); + unsigned int i; + + 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]); + } } } } -- 2.34.1