[PATCH] ASoC: Intel: catpt: Fix the device initialization

[Cezary Rojewski <cezary.rojewski@intel.com>]

The DMA mask shall be coerced before any buffer allocations for the
device are done.  At the same time explain why DMA mask of 31 bits is
used in the first place.

Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Fixes: 7a10b66a5df9 ("ASoC: Intel: catpt: Device driver lifecycle")
Signed-off-by: Cezary Rojewski <cezary.rojewski@intel.com>
---
 sound/soc/intel/catpt/device.c | 10 +++++++++-
 sound/soc/intel/catpt/dsp.c    |  3 ---
 2 files changed, 9 insertions(+), 4 deletions(-)

diff --git a/sound/soc/intel/catpt/device.c b/sound/soc/intel/catpt/device.c
index b5f4361d4465..ca4fd18b6a6e 100644
--- a/sound/soc/intel/catpt/device.c
+++ b/sound/soc/intel/catpt/device.c
@@ -281,7 +281,15 @@ static int catpt_acpi_probe(struct platform_device *pdev)
 	if (IS_ERR(cdev->pci_ba))
 		return PTR_ERR(cdev->pci_ba);
 
-	/* alloc buffer for storing DRAM context during dx transitions */
+	/*
+	 * As per design HOST is responsible for preserving firmware's runtime
+	 * context during D0 -> D3 -> D0 transitions.  Addresses used for DMA
+	 * to/from HOST memory shall be outside the reserved range of 0xFFFxxxxx.
+	 */
+	ret = dma_coerce_mask_and_coherent(cdev->dev, DMA_BIT_MASK(31));
+	if (ret)
+		return ret;
+
 	cdev->dxbuf_vaddr = dmam_alloc_coherent(dev, catpt_dram_size(cdev),
 						&cdev->dxbuf_paddr, GFP_KERNEL);
 	if (!cdev->dxbuf_vaddr)
diff --git a/sound/soc/intel/catpt/dsp.c b/sound/soc/intel/catpt/dsp.c
index 008a20a2acbd..677f348909c8 100644
--- a/sound/soc/intel/catpt/dsp.c
+++ b/sound/soc/intel/catpt/dsp.c
@@ -125,9 +125,6 @@ int catpt_dmac_probe(struct catpt_dev *cdev)
 	dmac->dev = cdev->dev;
 	dmac->irq = cdev->irq;
 
-	ret = dma_coerce_mask_and_coherent(cdev->dev, DMA_BIT_MASK(31));
-	if (ret)
-		return ret;
 	/*
 	 * Caller is responsible for putting device in D0 to allow
 	 * for I/O and memory access before probing DW.
-- 
2.34.1