[PATCHv2] spi_mpc8xxx: fix WARN_ON on remove after 4c1fba44296

[Peter Korsgaard <jacmet@sunsite.dk>]

Commit 4c1fba44296 (Add support for QE DMA mode and CPM1/CPM2 chips)
added unconditional calls to _cpm_init() / _cpm_free() from
probe()/remove(), but only checked if we're actually using CPM mode
in _init(), causing the WARN_ON in mpc8xxx_spi_free_dummy_rx() for !CPM.

Fix it by adding the same check in _cpm_free() as well.

Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk>
---
 drivers/spi/spi_mpc8xxx.c |    3 +++
 1 files changed, 3 insertions(+), 0 deletions(-)

Changes since v1:
Fix return statement, mpc8xxx_spi_cpm_free() has void return type.
diff --git a/drivers/spi/spi_mpc8xxx.c b/drivers/spi/spi_mpc8xxx.c
index 1fb2a6e..674e7a2 100644
--- a/drivers/spi/spi_mpc8xxx.c
+++ b/drivers/spi/spi_mpc8xxx.c
@@ -946,6 +946,9 @@ static void mpc8xxx_spi_cpm_free(struct mpc8xxx_spi *mspi)
 {
 	struct device *dev = mspi->dev;
 
+	if (!(mspi->flags & SPI_CPM_MODE))
+		return;
+
 	dma_unmap_single(dev, mspi->dma_dummy_rx, SPI_MRBLR, DMA_FROM_DEVICE);
 	dma_unmap_single(dev, mspi->dma_dummy_tx, PAGE_SIZE, DMA_TO_DEVICE);
 	cpm_muram_free(cpm_muram_offset(mspi->tx_bd));
-- 
1.6.5