[PATCH 03/15] staging: comedi: pcl816: remove depends on ISA_DMA_API limitation
H Hartley Sweeten
hsweeten at visionengravers.com
Wed Jan 14 17:05:04 UTC 2015
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 at visionengravers.com>
Cc: Ian Abbott <abbotti at mev.co.uk>
Cc: Greg Kroah-Hartman <gregkh at linuxfoundation.org>
---
drivers/staging/comedi/Kconfig | 2 +-
drivers/staging/comedi/drivers/pcl816.c | 208 +++++++++++---------------------
2 files changed, 70 insertions(+), 140 deletions(-)
diff --git a/drivers/staging/comedi/Kconfig b/drivers/staging/comedi/Kconfig
index 4c9e2a8..1ed797b 100644
--- 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
--- 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)
--
2.0.3
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