#include <linux/module.h>
#include <linux/slab.h>
-#include "../comedidev.h"
-#include <asm/dma.h>
+#include "../comedidev.h"
+#include "comedi_isadma.h"
#include "comedi_fc.h"
#include "ni_labpc.h"
#include "ni_labpc_regs.h"
#include "ni_labpc_isadma.h"
/* size in bytes of dma buffer */
-static const int dma_buffer_size = 0xff00;
-/* 2 bytes per sample */
-static const int sample_size = 2;
+#define LABPC_ISADMA_BUFFER_SIZE 0xff00
/* utility function that suggests a dma transfer size in bytes */
-static unsigned int labpc_suggest_transfer_size(const struct comedi_cmd *cmd)
+static unsigned int labpc_suggest_transfer_size(struct comedi_device *dev,
+ struct comedi_subdevice *s,
+ unsigned int maxbytes)
{
+ struct comedi_cmd *cmd = &s->async->cmd;
+ unsigned int sample_size = comedi_bytes_per_sample(s);
unsigned int size;
unsigned int freq;
size = (freq / 3) * sample_size;
/* set a minimum and maximum size allowed */
- if (size > dma_buffer_size)
- size = dma_buffer_size - dma_buffer_size % sample_size;
+ if (size > maxbytes)
+ size = maxbytes;
else if (size < sample_size)
size = sample_size;
void labpc_setup_dma(struct comedi_device *dev, struct comedi_subdevice *s)
{
struct labpc_private *devpriv = dev->private;
+ struct comedi_isadma_desc *desc = &devpriv->dma->desc[0];
struct comedi_cmd *cmd = &s->async->cmd;
- unsigned long irq_flags;
-
- irq_flags = claim_dma_lock();
- disable_dma(devpriv->dma_chan);
- /* clear flip-flop to make sure 2-byte registers for
- * count and address get set correctly */
- clear_dma_ff(devpriv->dma_chan);
- set_dma_addr(devpriv->dma_chan, devpriv->dma_addr);
+ unsigned int sample_size = comedi_bytes_per_sample(s);
+
/* set appropriate size of transfer */
- devpriv->dma_transfer_size = labpc_suggest_transfer_size(cmd);
+ desc->size = labpc_suggest_transfer_size(dev, s, desc->maxsize);
if (cmd->stop_src == TRIG_COUNT &&
- devpriv->count * sample_size < devpriv->dma_transfer_size)
- devpriv->dma_transfer_size = devpriv->count * sample_size;
- set_dma_count(devpriv->dma_chan, devpriv->dma_transfer_size);
- enable_dma(devpriv->dma_chan);
- release_dma_lock(irq_flags);
+ devpriv->count * sample_size < desc->size)
+ desc->size = devpriv->count * sample_size;
+
+ comedi_isadma_program(desc);
+
/* set CMD3 bits for caller to enable DMA and interrupt */
devpriv->cmd3 |= (CMD3_DMAEN | CMD3_DMATCINTEN);
}
void labpc_drain_dma(struct comedi_device *dev)
{
struct labpc_private *devpriv = dev->private;
+ struct comedi_isadma_desc *desc = &devpriv->dma->desc[0];
struct comedi_subdevice *s = dev->read_subdev;
struct comedi_async *async = s->async;
struct comedi_cmd *cmd = &async->cmd;
- int status;
- unsigned long flags;
- unsigned int max_points, num_points, residue, leftover;
+ unsigned int max_samples = comedi_bytes_to_samples(s, desc->size);
+ unsigned int residue;
+ unsigned int nsamples;
+ unsigned int leftover;
- status = devpriv->stat1;
-
- flags = claim_dma_lock();
- disable_dma(devpriv->dma_chan);
- /* clear flip-flop to make sure 2-byte registers for
- * count and address get set correctly */
- clear_dma_ff(devpriv->dma_chan);
-
- /* figure out how many points to read */
- max_points = devpriv->dma_transfer_size / sample_size;
- /* residue is the number of points left to be done on the dma
+ /*
+ * residue is the number of bytes left to be done on the dma
* transfer. It should always be zero at this point unless
* the stop_src is set to external triggering.
*/
- residue = get_dma_residue(devpriv->dma_chan) / sample_size;
- num_points = max_points - residue;
- if (cmd->stop_src == TRIG_COUNT && devpriv->count < num_points)
- num_points = devpriv->count;
-
- /* figure out how many points will be stored next time */
- leftover = 0;
- if (cmd->stop_src != TRIG_COUNT) {
- leftover = devpriv->dma_transfer_size / sample_size;
- } else if (devpriv->count > num_points) {
- leftover = devpriv->count - num_points;
- if (leftover > max_points)
- leftover = max_points;
- }
-
- comedi_buf_write_samples(s, devpriv->dma_buffer, num_points);
+ residue = comedi_isadma_disable(desc->chan);
- if (cmd->stop_src == TRIG_COUNT)
- devpriv->count -= num_points;
+ /*
+ * Figure out how many samples to read for this transfer and
+ * how many will be stored for next time.
+ */
+ nsamples = max_samples - comedi_bytes_to_samples(s, residue);
+ if (cmd->stop_src == TRIG_COUNT) {
+ if (devpriv->count <= nsamples) {
+ nsamples = devpriv->count;
+ leftover = 0;
+ } else {
+ leftover = devpriv->count - nsamples;
+ if (leftover > max_samples)
+ leftover = max_samples;
+ }
+ devpriv->count -= nsamples;
+ } else {
+ leftover = max_samples;
+ }
+ desc->size = comedi_samples_to_bytes(s, leftover);
- /* set address and count for next transfer */
- set_dma_addr(devpriv->dma_chan, devpriv->dma_addr);
- set_dma_count(devpriv->dma_chan, leftover * sample_size);
- release_dma_lock(flags);
+ comedi_buf_write_samples(s, desc->virt_addr, nsamples);
}
EXPORT_SYMBOL_GPL(labpc_drain_dma);
static void handle_isa_dma(struct comedi_device *dev)
{
struct labpc_private *devpriv = dev->private;
+ struct comedi_isadma_desc *desc = &devpriv->dma->desc[0];
labpc_drain_dma(dev);
- enable_dma(devpriv->dma_chan);
+ if (desc->size)
+ comedi_isadma_program(desc);
/* clear dma tc interrupt */
devpriv->write_byte(dev, 0x1, DMATC_CLEAR_REG);
}
EXPORT_SYMBOL_GPL(labpc_handle_dma_status);
-int labpc_init_dma_chan(struct comedi_device *dev, unsigned int dma_chan)
+void labpc_init_dma_chan(struct comedi_device *dev, unsigned int dma_chan)
{
struct labpc_private *devpriv = dev->private;
- void *dma_buffer;
- unsigned long dma_flags;
- int ret;
+ /* only DMA channels 3 and 1 are valid */
if (dma_chan != 1 && dma_chan != 3)
- return -EINVAL;
-
- dma_buffer = kmalloc(dma_buffer_size, GFP_KERNEL | GFP_DMA);
- if (!dma_buffer)
- return -ENOMEM;
-
- ret = request_dma(dma_chan, dev->board_name);
- if (ret) {
- kfree(dma_buffer);
- return ret;
- }
-
- devpriv->dma_buffer = dma_buffer;
- devpriv->dma_chan = dma_chan;
- devpriv->dma_addr = virt_to_bus(devpriv->dma_buffer);
-
- dma_flags = claim_dma_lock();
- disable_dma(devpriv->dma_chan);
- set_dma_mode(devpriv->dma_chan, DMA_MODE_READ);
- release_dma_lock(dma_flags);
+ return;
- return 0;
+ /* DMA uses 1 buffer */
+ devpriv->dma = comedi_isadma_alloc(dev, 1, dma_chan, dma_chan,
+ LABPC_ISADMA_BUFFER_SIZE,
+ COMEDI_ISADMA_READ);
}
EXPORT_SYMBOL_GPL(labpc_init_dma_chan);
{
struct labpc_private *devpriv = dev->private;
- kfree(devpriv->dma_buffer);
- devpriv->dma_buffer = NULL;
- if (devpriv->dma_chan) {
- free_dma(devpriv->dma_chan);
- devpriv->dma_chan = 0;
- }
+ if (devpriv)
+ comedi_isadma_free(devpriv->dma);
}
EXPORT_SYMBOL_GPL(labpc_free_dma_chan);
projects / firefly-linux-kernel-4.4.55.git / blobdiff