[U-Boot] [PATCH] spi: oc_tiny_spi: Refactor to simplify spi_xfer implementation

Currently we have similar code for (txp && rxp), (txp && !rxp), (!rxp & txp), and (!txp && !rxp) cases. This patch refactors the code a bit to avoid duplicate similar code.

Signed-off-by: Axel Lin axel.lin@ingics.com --- Hi Thomas, This path is similar to the patch I sent for spi-oc-tiny.c linux driver. I'd appreciate if you can review and test this patch. Regards, Axel drivers/spi/oc_tiny_spi.c | 85 ++++++----------------------------------------- 1 file changed, 11 insertions(+), 74 deletions(-)

diff --git a/drivers/spi/oc_tiny_spi.c b/drivers/spi/oc_tiny_spi.c index 4de5d00..a8c1dfd 100644 --- a/drivers/spi/oc_tiny_spi.c +++ b/drivers/spi/oc_tiny_spi.c @@ -158,85 +158,22 @@ int spi_xfer(struct spi_slave *slave, unsigned int bitlen, const void *dout, spi_cs_activate(slave);

/* we need to tighten the transfer loop */ - if (txp && rxp) { - writeb(*txp++, &regs->txdata); - if (bytes > 1) { - writeb(*txp++, &regs->txdata); - for (i = 2; i < bytes; i++) { - u8 rx, tx = *txp++; - while (!(readb(&regs->status) & - TINY_SPI_STATUS_TXR)) + writeb(txp ? *txp++ : CONFIG_TINY_SPI_IDLE_VAL, &regs->txdata); + for (i = 1; i < bytes; i++) { + writeb(txp ? *txp++ : CONFIG_TINY_SPI_IDLE_VAL, &regs->txdata); + + if (rxp || (i != bytes - 1)) { + while (!(readb(&regs->status) & TINY_SPI_STATUS_TXR)) ; - rx = readb(&regs->txdata); - writeb(tx, &regs->txdata); - *rxp++ = rx; - } - while (!(readb(&regs->status) & - TINY_SPI_STATUS_TXR)) - ; - *rxp++ = readb(&regs->txdata); } - while (!(readb(&regs->status) & - TINY_SPI_STATUS_TXE)) - ; - *rxp++ = readb(&regs->rxdata); - } else if (rxp) { - writeb(CONFIG_TINY_SPI_IDLE_VAL, &regs->txdata); - if (bytes > 1) { - writeb(CONFIG_TINY_SPI_IDLE_VAL, - &regs->txdata); - for (i = 2; i < bytes; i++) { - u8 rx; - while (!(readb(&regs->status) & - TINY_SPI_STATUS_TXR)) - ; - rx = readb(&regs->txdata); - writeb(CONFIG_TINY_SPI_IDLE_VAL, - &regs->txdata); - *rxp++ = rx; - } - while (!(readb(&regs->status) & - TINY_SPI_STATUS_TXR)) - ; + + if (rxp) *rxp++ = readb(&regs->txdata); - } - while (!(readb(&regs->status) & - TINY_SPI_STATUS_TXE)) + } + while (!(readb(&regs->status) & TINY_SPI_STATUS_TXE)) ; + if (rxp) *rxp++ = readb(&regs->rxdata); - } else if (txp) { - writeb(*txp++, &regs->txdata); - if (bytes > 1) { - writeb(*txp++, &regs->txdata); - for (i = 2; i < bytes; i++) { - u8 tx = *txp++; - while (!(readb(&regs->status) & - TINY_SPI_STATUS_TXR)) - ; - writeb(tx, &regs->txdata); - } - } - while (!(readb(&regs->status) & - TINY_SPI_STATUS_TXE)) - ; - } else { - writeb(CONFIG_TINY_SPI_IDLE_VAL, &regs->txdata); - if (bytes > 1) { - writeb(CONFIG_TINY_SPI_IDLE_VAL, - &regs->txdata); - for (i = 2; i < bytes; i++) { - while (!(readb(&regs->status) & - TINY_SPI_STATUS_TXR)) - ; - writeb(CONFIG_TINY_SPI_IDLE_VAL, - &regs->txdata); - } - } - while (!(readb(&regs->status) & - TINY_SPI_STATUS_TXE)) - ; - } - done: if (flags & SPI_XFER_END) spi_cs_deactivate(slave);