diff options
| author | Axel Lin <axel.lin@ingics.com> | 2013-08-15 14:18:46 +0800 |
|---|---|---|
| committer | Mark Brown <broonie@linaro.org> | 2013-08-28 14:18:45 +0100 |
| commit | 72be0ee42ebaf744d4a5cf684ee68dba59d6bac1 (patch) | |
| tree | 09e081812af8a2da2b288d8e1ea30fdf31853edc /drivers/spi/spi-altera.c | |
| parent | d8dfad3876e4386666b759da3c833d62fb8b2267 (diff) | |
spi: altera: Simplify altera_spi_txrx implementation for noirq case
This patch simplifies the code and makes it better in readability.
Now the logic in the while loop is simply
"write to ALTERA_SPI_TXDATA then read from ALTERA_SPI_TXDATA".
There is a slightly logic change because now we avoid a read-write cycle when
hw->len is 0. Since the code in bitbang library will call bitbang->txrx_bufs()
only when t->len is not 0, this is not a problem.
Signed-off-by: Axel Lin <axel.lin@ingics.com>
Acked-by: Thomas Chou <thomas@wytron.com.tw>
Signed-off-by: Mark Brown <broonie@linaro.org>
Diffstat (limited to 'drivers/spi/spi-altera.c')
| -rw-r--r-- | drivers/spi/spi-altera.c | 15 |
1 files changed, 4 insertions, 11 deletions
diff --git a/drivers/spi/spi-altera.c b/drivers/spi/spi-altera.c index 81b9adb6e766..453fa5ac04ad 100644 --- a/drivers/spi/spi-altera.c +++ b/drivers/spi/spi-altera.c @@ -150,12 +150,12 @@ static int altera_spi_txrx(struct spi_device *spi, struct spi_transfer *t) hw->imr &= ~ALTERA_SPI_CONTROL_IRRDY_MSK; writel(hw->imr, hw->base + ALTERA_SPI_CONTROL); } else { - /* send the first byte */ - writel(hw_txbyte(hw, 0), hw->base + ALTERA_SPI_TXDATA); - - while (1) { + while (hw->count < hw->len) { unsigned int rxd; + writel(hw_txbyte(hw, hw->count), + hw->base + ALTERA_SPI_TXDATA); + while (!(readl(hw->base + ALTERA_SPI_STATUS) & ALTERA_SPI_STATUS_RRDY_MSK)) cpu_relax(); @@ -174,14 +174,7 @@ static int altera_spi_txrx(struct spi_device *spi, struct spi_transfer *t) } hw->count++; - - if (hw->count < hw->len) - writel(hw_txbyte(hw, hw->count), - hw->base + ALTERA_SPI_TXDATA); - else - break; } - } return hw->count * hw->bytes_per_word; |