The read an writes from the fifo are from a buffer with various fields and data at predefined offsets. So, they reads and writes should not be done to the same address(or port) in case of val_count greater than 1. Therefore, fix this by using iowrite32/ioread32 instead of ioread32_rep/iowrite32_rep. Also, the write into fifo must be performed with an offset from the message ram base address. Therefore, fix the base address to mram_base. Fixes: e39381770ec9 ("can: m_can: Disable IRQs on FIFO bus errors") Signed-off-by: Aswath Govindraju <a-govindraju@xxxxxx> --- drivers/net/can/m_can/m_can_platform.c | 14 ++++++++++++-- 1 file changed, 12 insertions(+), 2 deletions(-) diff --git a/drivers/net/can/m_can/m_can_platform.c b/drivers/net/can/m_can/m_can_platform.c index 308d4f2fff00..eee47bad0592 100644 --- a/drivers/net/can/m_can/m_can_platform.c +++ b/drivers/net/can/m_can/m_can_platform.c @@ -32,8 +32,13 @@ static u32 iomap_read_reg(struct m_can_classdev *cdev, int reg) static int iomap_read_fifo(struct m_can_classdev *cdev, int offset, void *val, size_t val_count) { struct m_can_plat_priv *priv = cdev_to_priv(cdev); + void __iomem *src = priv->mram_base + offset; - ioread32_rep(priv->mram_base + offset, val, val_count); + while (val_count--) { + *(unsigned int *)val = ioread32(src); + val += 4; + src += 4; + } return 0; } @@ -51,8 +56,13 @@ static int iomap_write_fifo(struct m_can_classdev *cdev, int offset, const void *val, size_t val_count) { struct m_can_plat_priv *priv = cdev_to_priv(cdev); + void __iomem *dst = priv->mram_base + offset; - iowrite32_rep(priv->base + offset, val, val_count); + while (val_count--) { + iowrite32(*(unsigned int *)val, dst); + val += 4; + dst += 4; + } return 0; } -- 2.17.1