From adef658ddf71e709eb1bdc181b86c62b933b967b Mon Sep 17 00:00:00 2001 From: Michael Jones Date: Fri, 25 Feb 2011 16:55:11 +0100 Subject: [PATCH] spi/omap_mcspi: catch xfers of non-multiple SPI word size If an SPI access was not a multiple of the SPI word size, the while() loop would spin and the rx/tx ptrs would be incremented indefinitely. Signed-off-by: Michael Jones Signed-off-by: Grant Likely --- drivers/spi/omap2_mcspi.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) diff --git a/drivers/spi/omap2_mcspi.c b/drivers/spi/omap2_mcspi.c index 1a2d0b8bdd6a..6a982a25b7c3 100644 --- a/drivers/spi/omap2_mcspi.c +++ b/drivers/spi/omap2_mcspi.c @@ -487,6 +487,9 @@ omap2_mcspi_txrx_pio(struct spi_device *spi, struct spi_transfer *xfer) rx_reg = base + OMAP2_MCSPI_RX0; chstat_reg = base + OMAP2_MCSPI_CHSTAT0; + if (c < (word_len>>3)) + return 0; + if (word_len <= 8) { u8 *rx; const u8 *tx; @@ -534,7 +537,7 @@ omap2_mcspi_txrx_pio(struct spi_device *spi, struct spi_transfer *xfer) dev_vdbg(&spi->dev, "read-%d %02x\n", word_len, *(rx - 1)); } - } while (c); + } while (c > (word_len>>3)); } else if (word_len <= 16) { u16 *rx; const u16 *tx; @@ -581,7 +584,7 @@ omap2_mcspi_txrx_pio(struct spi_device *spi, struct spi_transfer *xfer) dev_vdbg(&spi->dev, "read-%d %04x\n", word_len, *(rx - 1)); } - } while (c); + } while (c > (word_len>>3)); } else if (word_len <= 32) { u32 *rx; const u32 *tx; @@ -628,7 +631,7 @@ omap2_mcspi_txrx_pio(struct spi_device *spi, struct spi_transfer *xfer) dev_vdbg(&spi->dev, "read-%d %08x\n", word_len, *(rx - 1)); } - } while (c); + } while (c > (word_len>>3)); } /* for TX_ONLY mode, be sure all words have shifted out */ -- 2.20.1