From 7995d74ab297e4f5526c8df70007e1e39f0d1f5c Mon Sep 17 00:00:00 2001 From: Alexander Stein Date: Wed, 26 Feb 2014 16:31:19 +0100 Subject: [PATCH] spi-topcliff-pch: Fix probing when DMA mode is used If during registering SPI master due to SPI device probing a SPI transfer is issued the DMA buffers are not allocated yet. This fixes the following oops: pch_spi 0000:02:0c.1: enabling device (0000 -> 0002) pch_spi 0000:02:0c.1: master is unqueued, this is deprecated BUG: unable to handle kernel NULL pointer dereference at (null) IP: [] pch_spi_handle_dma+0x15c/0x6f4 [...] Signed-off-by: Alexander Stein Signed-off-by: Mark Brown --- drivers/spi/spi-topcliff-pch.c | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-) diff --git a/drivers/spi/spi-topcliff-pch.c b/drivers/spi/spi-topcliff-pch.c index 3383008c..88eb57e 100644 --- a/drivers/spi/spi-topcliff-pch.c +++ b/drivers/spi/spi-topcliff-pch.c @@ -1452,6 +1452,11 @@ static int pch_spi_pd_probe(struct platform_device *plat_dev) pch_spi_set_master_mode(master); + if (use_dma) { + dev_info(&plat_dev->dev, "Use DMA for data transfers\n"); + pch_alloc_dma_buf(board_dat, data); + } + ret = spi_register_master(master); if (ret != 0) { dev_err(&plat_dev->dev, @@ -1459,14 +1464,10 @@ static int pch_spi_pd_probe(struct platform_device *plat_dev) goto err_spi_register_master; } - if (use_dma) { - dev_info(&plat_dev->dev, "Use DMA for data transfers\n"); - pch_alloc_dma_buf(board_dat, data); - } - return 0; err_spi_register_master: + pch_free_dma_buf(board_dat, data); free_irq(board_dat->pdev->irq, data); err_request_irq: pch_spi_free_resources(board_dat, data); -- 2.7.4