From 6d26275177e9fb086273944b3e8fc51db5aff460 Mon Sep 17 00:00:00 2001 From: H Hartley Sweeten Date: Mon, 12 Jan 2015 10:55:51 -0700 Subject: [PATCH] staging: comedi: ni_at_a2150: remove VIRT_TO_BUS dependancy Use dma_{alloc,free}_coherent() to allocate and free the DMA buffers. This removes the dependancy on VIRT_TO_BUS. Signed-off-by: H Hartley Sweeten Reviewed-by: Ian Abbott Signed-off-by: Greg Kroah-Hartman --- drivers/staging/comedi/Kconfig | 2 +- drivers/staging/comedi/drivers/ni_at_a2150.c | 17 +++++++++++------ 2 files changed, 12 insertions(+), 7 deletions(-) diff --git a/drivers/staging/comedi/Kconfig b/drivers/staging/comedi/Kconfig index fe030a33d291..982b03f79b36 100644 --- a/drivers/staging/comedi/Kconfig +++ b/drivers/staging/comedi/Kconfig @@ -462,7 +462,7 @@ config COMEDI_ADQ12B config COMEDI_NI_AT_A2150 tristate "NI AT-A2150 ISA card support" - depends on VIRT_TO_BUS && ISA_DMA_API + depends on ISA_DMA_API ---help--- Enable support for National Instruments AT-A2150 cards diff --git a/drivers/staging/comedi/drivers/ni_at_a2150.c b/drivers/staging/comedi/drivers/ni_at_a2150.c index a1300e0b7900..3905097ef6d8 100644 --- a/drivers/staging/comedi/drivers/ni_at_a2150.c +++ b/drivers/staging/comedi/drivers/ni_at_a2150.c @@ -147,7 +147,8 @@ static const struct a2150_board a2150_boards[] = { struct a2150_dma_desc { unsigned int chan; /* DMA channel */ - uint16_t *virt_addr; /* virtual address of DMA buffer */ + void *virt_addr; /* virtual address of DMA buffer */ + dma_addr_t hw_addr; /* hardware (bus) address of DMA buffer */ unsigned int size; /* size of DMA transfer (in bytes) */ }; @@ -170,6 +171,7 @@ static irqreturn_t a2150_interrupt(int irq, void *d) struct comedi_subdevice *s = dev->read_subdev; struct comedi_async *async; struct comedi_cmd *cmd; + unsigned short *buf = dma->virt_addr; unsigned int max_points, num_points, residue, leftover; unsigned short dpnt; @@ -237,7 +239,7 @@ static irqreturn_t a2150_interrupt(int irq, void *d) for (i = 0; i < num_points; i++) { /* write data point to comedi buffer */ - dpnt = dma->virt_addr[i]; + dpnt = buf[i]; /* convert from 2's complement to unsigned coding */ dpnt ^= 0x8000; comedi_buf_write_samples(s, &dpnt, 1); @@ -250,7 +252,7 @@ static irqreturn_t a2150_interrupt(int irq, void *d) } /* re-enable dma */ if (leftover) { - set_dma_addr(dma->chan, virt_to_bus(dma->virt_addr)); + set_dma_addr(dma->chan, dma->hw_addr); set_dma_count(dma->chan, comedi_samples_to_bytes(s, leftover)); enable_dma(dma->chan); @@ -553,7 +555,7 @@ static int a2150_ai_cmd(struct comedi_device *dev, struct comedi_subdevice *s) /* clear flip-flop to make sure 2-byte registers for * count and address get set correctly */ clear_dma_ff(dma->chan); - set_dma_addr(dma->chan, virt_to_bus(dma->virt_addr)); + set_dma_addr(dma->chan, dma->hw_addr); /* set size of transfer to fill in 1/3 second */ #define ONE_THIRD_SECOND 333333333 dma->size = comedi_bytes_per_sample(s) * cmd->chanlist_len * @@ -709,7 +711,8 @@ static void a2150_alloc_irq_dma(struct comedi_device *dev, free_irq(irq_num, dev); return; } - dma->virt_addr = kmalloc(A2150_DMA_BUFFER_SIZE, GFP_KERNEL | GFP_DMA); + dma->virt_addr = dma_alloc_coherent(NULL, A2150_DMA_BUFFER_SIZE, + &dma->hw_addr, GFP_KERNEL); if (!dma->virt_addr) { free_dma(dma_chan); free_irq(irq_num, dev); @@ -735,7 +738,9 @@ static void a2150_free_dma(struct comedi_device *dev) dma = &devpriv->dma_desc; if (dma->chan) free_dma(dma->chan); - kfree(dma->virt_addr); + if (dma->virt_addr) + dma_free_coherent(NULL, A2150_DMA_BUFFER_SIZE, + dma->virt_addr, dma->hw_addr); } /* probes board type, returns offset */ -- 2.20.1