DMAENGINE: generic slave control v2

Convert the device_terminate_all() operation on the
DMA engine to a generic device_control() operation
which can now optionally support also pausing and
resuming DMA on a certain channel. Implemented for the
COH 901 318 DMAC as an example.

[dan.j.williams@intel.com: update for timberdale]
Signed-off-by: Linus Walleij <linus.walleij@stericsson.com>
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Cc: Maciej Sosnowski <maciej.sosnowski@intel.com>
Cc: Nicolas Ferre <nicolas.ferre@atmel.com>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Li Yang <leoli@freescale.com>
Cc: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Haavard Skinnemoen <haavard.skinnemoen@atmel.com>
Cc: Magnus Damm <damm@opensource.se>
Cc: Liam Girdwood <lrg@slimlogic.co.uk>
Cc: Joe Perches <joe@perches.com>
Cc: Roland Dreier <rdreier@cisco.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

1 files changed, 10 insertions, 3 deletions

diff --git a/drivers/dma/fsldma.c b/drivers/dma/fsldma.c
index bbb4be5a3ff4..714fc46e7695 100644
--- a/drivers/dma/fsldma.c
+++ b/drivers/dma/fsldma.c
@@ -774,13 +774,18 @@ fail:
         return NULL;
 }
 
-static void fsl_dma_device_terminate_all(struct dma_chan *dchan)
+static int fsl_dma_device_control(struct dma_chan *dchan,
+                                  enum dma_ctrl_cmd cmd)
 {
         struct fsldma_chan *chan;
         unsigned long flags;
 
+        /* Only supports DMA_TERMINATE_ALL */
+        if (cmd != DMA_TERMINATE_ALL)
+                return -ENXIO;
+
         if (!dchan)
-                return;
+                return -EINVAL;
 
         chan = to_fsl_chan(dchan);
 
@@ -794,6 +799,8 @@ static void fsl_dma_device_terminate_all(struct dma_chan *dchan)
         fsldma_free_desc_list(chan, &chan->ld_running);
 
         spin_unlock_irqrestore(&chan->desc_lock, flags);
+
+        return 0;
 }
 
 /**
@@ -1332,7 +1339,7 @@ static int __devinit fsldma_of_probe(struct of_device *op,
         fdev->common.device_is_tx_complete = fsl_dma_is_complete;
         fdev->common.device_issue_pending = fsl_dma_memcpy_issue_pending;
         fdev->common.device_prep_slave_sg = fsl_dma_prep_slave_sg;
-        fdev->common.device_terminate_all = fsl_dma_device_terminate_all;
+        fdev->common.device_control = fsl_dma_device_control;
         fdev->common.dev = &op->dev;
 
         dev_set_drvdata(&op->dev, fdev);