staging: comedi: pcl816: remove depends on ISA_DMA_API limitation

Use the new comedi_isadma module to provide the ISA DMA support. This removes
all the ISA_DMA_API code from this driver and allows the driver to be used on
platforms that don't support the ISA_DMA_API.

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>

diff --git a/drivers/staging/comedi/Kconfig b/drivers/staging/comedi/Kconfig
index 4c9e2a8..1ed797b 100644 (file)
--- a/drivers/staging/comedi/Kconfig
+++ b/drivers/staging/comedi/Kconfig
@@ -179,7 +179,7 @@ config COMEDI_PCL812
 
 config COMEDI_PCL816
        tristate "Advantech PCL-814 and PCL-816 ISA card support"
-       depends on ISA_DMA_API
+       select COMEDI_ISADMA if ISA_DMA_API
        ---help---
          Enable support for Advantech PCL-814 and PCL-816 ISA cards
 

diff --git a/drivers/staging/comedi/drivers/pcl816.c b/drivers/staging/comedi/drivers/pcl816.c
index d2ce775..09fa409 100644 (file)
--- a/drivers/staging/comedi/drivers/pcl816.c
+++ b/drivers/staging/comedi/drivers/pcl816.c
@@ -33,14 +33,14 @@ Configuration Options:
 */
 
 #include <linux/module.h>
-#include "../comedidev.h"
-
 #include <linux/gfp.h>
 #include <linux/delay.h>
 #include <linux/io.h>
 #include <linux/interrupt.h>
-#include <asm/dma.h>
 
+#include "../comedidev.h"
+
+#include "comedi_isadma.h"
 #include "comedi_fc.h"
 #include "8253.h"
 
@@ -113,17 +113,8 @@ static const struct pcl816_board boardtypes[] = {
        },
 };
 
-struct pcl816_dma_desc {
-       void *virt_addr;        /* virtual address of DMA buffer */
-       dma_addr_t hw_addr;     /* hardware (bus) address of DMA buffer */
-       unsigned int size;      /* transfer size (in bytes) */
-};
-
 struct pcl816_private {
-       unsigned int dma;       /*  used DMA, 0=don't use DMA */
-       unsigned int hwdmasize;
-       struct pcl816_dma_desc dma_desc[2];
-       int cur_dma;
+       struct comedi_isadma *dma;
        long dma_runs_to_end;   /*  how many we must permorm DMA transfer to end of record */
        unsigned long last_dma_run;     /*  how many bytes we must transfer on last DMA page */
        unsigned int ai_poll_ptr;       /*  how many sampes transfer poll */
@@ -133,29 +124,6 @@ struct pcl816_private {
        unsigned int ai_cmd_canceled:1;
 };
 
-static void pcl816_isadma_program(unsigned int dma_chan,
-                                 struct pcl816_dma_desc *dma)
-{
-       unsigned long flags;
-
-       flags = claim_dma_lock();
-       clear_dma_ff(dma_chan);
-       set_dma_mode(dma_chan, DMA_MODE_READ);
-       set_dma_addr(dma_chan, dma->hw_addr);
-       set_dma_count(dma_chan, dma->size);
-       enable_dma(dma_chan);
-       release_dma_lock(flags);
-}
-
-static void pcl816_isadma_disable(unsigned int dma_chan)
-{
-       unsigned long flags;
-
-       flags = claim_dma_lock();
-       disable_dma(dma_chan);
-       release_dma_lock(flags);
-}
-
 static void pcl816_start_pacer(struct comedi_device *dev, bool load_counters)
 {
        struct pcl816_private *devpriv = dev->private;
@@ -179,29 +147,30 @@ static void pcl816_ai_setup_dma(struct comedi_device *dev,
                                struct comedi_subdevice *s)
 {
        struct pcl816_private *devpriv = dev->private;
-       struct pcl816_dma_desc *dma = &devpriv->dma_desc[0];
+       struct comedi_isadma *dma = devpriv->dma;
+       struct comedi_isadma_desc *desc = &dma->desc[0];
        struct comedi_cmd *cmd = &s->async->cmd;
 
        if (cmd->stop_src == TRIG_COUNT) {
                /*  how many */
-               dma->size = cmd->stop_arg * comedi_bytes_per_scan(s);
+               desc->size = cmd->stop_arg * comedi_bytes_per_scan(s);
 
                /*  how many DMA pages we must fill */
-               devpriv->dma_runs_to_end = dma->size / devpriv->hwdmasize;
+               devpriv->dma_runs_to_end = desc->size / desc->maxsize;
 
                /* on last dma transfer must be moved */
-               devpriv->last_dma_run = dma->size % devpriv->hwdmasize;
+               devpriv->last_dma_run = desc->size % desc->maxsize;
                devpriv->dma_runs_to_end--;
                if (devpriv->dma_runs_to_end >= 0)
-                       dma->size = devpriv->hwdmasize;
+                       desc->size = desc->maxsize;
        } else {
-               dma->size = devpriv->hwdmasize;
+               desc->size = desc->maxsize;
                devpriv->dma_runs_to_end = -1;
        }
 
-       devpriv->cur_dma = 0;
+       dma->cur_dma = 0;
 
-       pcl816_isadma_program(devpriv->dma, dma);
+       comedi_isadma_program(desc);
 }
 
 static void pcl816_ai_setup_next_dma(struct comedi_device *dev,
@@ -209,19 +178,21 @@ static void pcl816_ai_setup_next_dma(struct comedi_device *dev,
 {
        struct pcl816_private *devpriv = dev->private;
        struct comedi_cmd *cmd = &s->async->cmd;
-       struct pcl816_dma_desc *dma;
+       struct comedi_isadma *dma = devpriv->dma;
+
+       comedi_isadma_disable(dma->chan);
+       dma->cur_dma = 1 - dma->cur_dma;
 
-       pcl816_isadma_disable(devpriv->dma);
+       /* switch dma bufs if still running */
        if (devpriv->dma_runs_to_end > -1 || cmd->stop_src == TRIG_NONE) {
-               /* switch dma bufs */
-               devpriv->cur_dma = 1 - devpriv->cur_dma;
-               dma = &devpriv->dma_desc[devpriv->cur_dma];
+               struct comedi_isadma_desc *desc = &dma->desc[dma->cur_dma];
+
                if (devpriv->dma_runs_to_end)
-                       dma->size = devpriv->hwdmasize;
+                       desc->size = desc->maxsize;
                else
-                       dma->size = devpriv->last_dma_run;
+                       desc->size = devpriv->last_dma_run;
 
-               pcl816_isadma_program(devpriv->dma, dma);
+               comedi_isadma_program(desc);
        }
 
        devpriv->dma_runs_to_end--;
@@ -337,7 +308,8 @@ static irqreturn_t pcl816_interrupt(int irq, void *d)
        struct comedi_device *dev = d;
        struct comedi_subdevice *s = dev->read_subdev;
        struct pcl816_private *devpriv = dev->private;
-       struct pcl816_dma_desc *dma = &devpriv->dma_desc[devpriv->cur_dma];
+       struct comedi_isadma *dma = devpriv->dma;
+       struct comedi_isadma_desc *desc = &dma->desc[dma->cur_dma];
        unsigned int nsamples;
        unsigned int bufptr;
 
@@ -354,11 +326,12 @@ static irqreturn_t pcl816_interrupt(int irq, void *d)
 
        pcl816_ai_setup_next_dma(dev, s);
 
-       nsamples = comedi_bytes_to_samples(s, dma->size) - devpriv->ai_poll_ptr;
+       nsamples = comedi_bytes_to_samples(s, desc->size) -
+                  devpriv->ai_poll_ptr;
        bufptr = devpriv->ai_poll_ptr;
        devpriv->ai_poll_ptr = 0;
 
-       transfer_from_dma_buf(dev, s, dma->virt_addr, bufptr, nsamples);
+       transfer_from_dma_buf(dev, s, desc->virt_addr, bufptr, nsamples);
 
        pcl816_ai_clear_eoc(dev);
 
@@ -500,6 +473,7 @@ static int pcl816_ai_cmdtest(struct comedi_device *dev,
 static int pcl816_ai_cmd(struct comedi_device *dev, struct comedi_subdevice *s)
 {
        struct pcl816_private *devpriv = dev->private;
+       struct comedi_isadma *dma = devpriv->dma;
        struct comedi_cmd *cmd = &s->async->cmd;
        unsigned int ctrl;
        unsigned int seglen;
@@ -530,7 +504,8 @@ static int pcl816_ai_cmd(struct comedi_device *dev, struct comedi_subdevice *s)
                ctrl |= PCL816_CTRL_EXT_TRIG;
 
        outb(ctrl, dev->iobase + PCL816_CTRL_REG);
-       outb((devpriv->dma << 4) | dev->irq, dev->iobase + PCL816_STATUS_REG);
+       outb((dma->chan << 4) | dev->irq,
+            dev->iobase + PCL816_STATUS_REG);
 
        return 0;
 }
@@ -538,41 +513,34 @@ static int pcl816_ai_cmd(struct comedi_device *dev, struct comedi_subdevice *s)
 static int pcl816_ai_poll(struct comedi_device *dev, struct comedi_subdevice *s)
 {
        struct pcl816_private *devpriv = dev->private;
-       struct pcl816_dma_desc *dma = &devpriv->dma_desc[devpriv->cur_dma];
+       struct comedi_isadma *dma = devpriv->dma;
+       struct comedi_isadma_desc *desc;
        unsigned long flags;
-       unsigned int top1, top2, i;
+       unsigned int poll;
+       int ret;
 
        spin_lock_irqsave(&dev->spinlock, flags);
 
-       for (i = 0; i < 20; i++) {
-               top1 = get_dma_residue(devpriv->dma);   /*  where is now DMA */
-               top2 = get_dma_residue(devpriv->dma);
-               if (top1 == top2)
-                       break;
-       }
-       if (top1 != top2) {
-               spin_unlock_irqrestore(&dev->spinlock, flags);
-               return 0;
-       }
-
-       /*  where is now DMA in buffer */
-       top1 = dma->size - top1;
-       top1 >>= 1;             /*  sample position */
-       top2 = top1 - devpriv->ai_poll_ptr;
-       if (top2 < 1) {         /*  no new samples */
-               spin_unlock_irqrestore(&dev->spinlock, flags);
-               return 0;
-       }
+       poll = comedi_isadma_poll(dma);
+       poll = comedi_bytes_to_samples(s, poll);
+       if (poll > devpriv->ai_poll_ptr) {
+               desc = &dma->desc[dma->cur_dma];
+               transfer_from_dma_buf(dev, s, desc->virt_addr,
+                                     devpriv->ai_poll_ptr,
+                                     poll - devpriv->ai_poll_ptr);
+               /* new buffer position */
+               devpriv->ai_poll_ptr = poll;
 
-       transfer_from_dma_buf(dev, s, dma->virt_addr,
-                             devpriv->ai_poll_ptr, top2);
+               comedi_handle_events(dev, s);
 
-       devpriv->ai_poll_ptr = top1;    /*  new buffer position */
+               ret = comedi_buf_n_bytes_ready(s);
+       } else {
+               /* no new samples */
+               ret = 0;
+       }
        spin_unlock_irqrestore(&dev->spinlock, flags);
 
-       comedi_handle_events(dev, s);
-
-       return comedi_buf_n_bytes_ready(s);
+       return ret;
 }
 
 static int pcl816_ai_cancel(struct comedi_device *dev,
@@ -673,68 +641,36 @@ static void pcl816_reset(struct comedi_device *dev)
        outb(0, dev->iobase + PCL816_DO_DI_MSB_REG);
 }
 
-static int pcl816_alloc_dma(struct comedi_device *dev,
-                           unsigned int irq_num, unsigned int dma_chan)
+static void pcl816_alloc_irq_and_dma(struct comedi_device *dev,
+                                    struct comedi_devconfig *it)
 {
        struct pcl816_private *devpriv = dev->private;
-       struct pcl816_dma_desc *dma;
-       int i;
+       unsigned int irq_num = it->options[1];
+       unsigned int dma_chan = it->options[2];
 
-       /*
-        * Only IRQs 2-7 are valid.
-        * Only DMA channels 3 and 1 are valid.
-        *
-        * Both must be valid for async command support.
-        */
+       /* only IRQs 2-7 and DMA channels 3 and 1 are valid */
        if (!(irq_num >= 2 && irq_num <= 7) ||
            !(dma_chan == 3 || dma_chan == 1))
-               return 0;
+               return;
 
-       /*
-        * Request the IRQ and DMA channels and allocate the DMA buffers.
-        * If the requests or allocations fail async command supprt will
-        * not be available.
-        */
        if (request_irq(irq_num, pcl816_interrupt, 0, dev->board_name, dev))
-               return 0;
-       if (request_dma(dma_chan, dev->board_name)) {
-               free_irq(irq_num, dev);
-               return 0;
-       }
-
-       dev->irq = irq_num;
-       devpriv->dma = dma_chan;
-
-       devpriv->hwdmasize = PAGE_SIZE * 4;     /* we need 16KB */
-
-       for (i = 0; i < 2; i++) {
-               dma = &devpriv->dma_desc[i];
+               return;
 
-               dma->virt_addr = dma_alloc_coherent(NULL, devpriv->hwdmasize,
-                                                   &dma->hw_addr, GFP_KERNEL);
-               if (!dma->virt_addr)
-                       return -ENOMEM;
-       }
-       return 0;
+       /* DMA uses two 16K buffers */
+       devpriv->dma = comedi_isadma_alloc(dev, 2, dma_chan, dma_chan,
+                                          PAGE_SIZE * 4, COMEDI_ISADMA_READ);
+       if (!devpriv->dma)
+               free_irq(irq_num, dev);
+       else
+               dev->irq = irq_num;
 }
 
 static void pcl816_free_dma(struct comedi_device *dev)
 {
        struct pcl816_private *devpriv = dev->private;
-       struct pcl816_dma_desc *dma;
-       int i;
 
-       if (!devpriv)
-               return;
-
-       if (devpriv->dma)
-               free_dma(devpriv->dma);
-       for (i = 0; i < 2; i++) {
-               dma = &devpriv->dma_desc[i];
-               if (dma->virt_addr)
-                       dma_free_coherent(NULL, devpriv->hwdmasize,
-                                         dma->virt_addr, dma->hw_addr);
-       }
+       if (devpriv)
+               comedi_isadma_free(devpriv->dma);
 }
 
 static int pcl816_attach(struct comedi_device *dev, struct comedi_devconfig *it)
@@ -752,14 +688,8 @@ static int pcl816_attach(struct comedi_device *dev, struct comedi_devconfig *it)
        if (ret)
                return ret;
 
-       /*
-        * An IRQ and DMA are required to support async commands.
-        * pcl816_alloc_dma() will only fail if the DMA buffers
-        * cannot be allocated.
-        */
-       ret = pcl816_alloc_dma(dev, it->options[1], it->options[2]);
-       if (ret)
-               return ret;
+       /* an IRQ and DMA are required to support async commands */
+       pcl816_alloc_irq_and_dma(dev, it);
 
        ret = comedi_alloc_subdevices(dev, 4);
        if (ret)