p54spi: fix incorrect access sequence to DMA_WRITE_CTRL in p54spi_spi_write_dma

Host is not allowed to modify DMA_WRITE_CTRL register
if bit HOST_ALLOWED in it is not set. Wait for HOST_ALLOWED first.

Also get rid of timeout in p54spi_wait_bit as it's been playing
a role of workaround for such an incorrect register access.

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
This commit is contained in:
Max Filippov 2009-05-18 03:02:31 +04:00 committed by John W. Linville
parent 4eaf16bc1f
commit 210dd1bb9b

View File

@ -172,8 +172,6 @@ static int p54spi_wait_bit(struct p54s_priv *priv, u16 reg, __le32 bits)
__le32 buffer = p54spi_read32(priv, reg);
if ((buffer & bits) == bits)
return 1;
msleep(0);
}
return 0;
}
@ -181,9 +179,6 @@ static int p54spi_wait_bit(struct p54s_priv *priv, u16 reg, __le32 bits)
static int p54spi_spi_write_dma(struct p54s_priv *priv, __le32 base,
const void *buf, size_t len)
{
p54spi_write16(priv, SPI_ADRS_DMA_WRITE_CTRL,
cpu_to_le16(SPI_DMA_WRITE_CTRL_ENABLE));
if (!p54spi_wait_bit(priv, SPI_ADRS_DMA_WRITE_CTRL,
cpu_to_le32(HOST_ALLOWED))) {
dev_err(&priv->spi->dev, "spi_write_dma not allowed "
@ -191,6 +186,9 @@ static int p54spi_spi_write_dma(struct p54s_priv *priv, __le32 base,
return -EAGAIN;
}
p54spi_write16(priv, SPI_ADRS_DMA_WRITE_CTRL,
cpu_to_le16(SPI_DMA_WRITE_CTRL_ENABLE));
p54spi_write16(priv, SPI_ADRS_DMA_WRITE_LEN, cpu_to_le16(len));
p54spi_write32(priv, SPI_ADRS_DMA_WRITE_BASE, base);
p54spi_spi_write(priv, SPI_ADRS_DMA_DATA, buf, len);