diff options
Diffstat (limited to 'drivers/spi/spi-xilinx.c')
| -rw-r--r-- | drivers/spi/spi-xilinx.c | 90 |
1 files changed, 35 insertions, 55 deletions
diff --git a/drivers/spi/spi-xilinx.c b/drivers/spi/spi-xilinx.c index e1d76960742..96b39284381 100644 --- a/drivers/spi/spi-xilinx.c +++ b/drivers/spi/spi-xilinx.c @@ -232,21 +232,6 @@ static int xilinx_spi_setup_transfer(struct spi_device *spi, return 0; } -static int xilinx_spi_setup(struct spi_device *spi) -{ - /* always return 0, we can not check the number of bits. - * There are cases when SPI setup is called before any driver is - * there, in that case the SPI core defaults to 8 bits, which we - * do not support in some cases. But if we return an error, the - * SPI device would not be registered and no driver can get hold of it - * When the driver is there, it will call SPI setup again with the - * correct number of bits per transfer. - * If a driver setups with the wrong bit number, it will fail when - * it tries to do a transfer - */ - return 0; -} - static void xilinx_spi_fill_tx_fifo(struct xilinx_spi *xspi) { u8 sr; @@ -267,7 +252,6 @@ static int xilinx_spi_txrx_bufs(struct spi_device *spi, struct spi_transfer *t) { struct xilinx_spi *xspi = spi_master_get_devdata(spi->master); u32 ipif_ier; - u16 cr; /* We get here with transmitter inhibited */ @@ -276,7 +260,6 @@ static int xilinx_spi_txrx_bufs(struct spi_device *spi, struct spi_transfer *t) xspi->remaining_bytes = t->len; INIT_COMPLETION(xspi->done); - xilinx_spi_fill_tx_fifo(xspi); /* Enable the transmit empty interrupt, which we use to determine * progress on the transmission. @@ -285,12 +268,41 @@ static int xilinx_spi_txrx_bufs(struct spi_device *spi, struct spi_transfer *t) xspi->write_fn(ipif_ier | XSPI_INTR_TX_EMPTY, xspi->regs + XIPIF_V123B_IIER_OFFSET); - /* Start the transfer by not inhibiting the transmitter any longer */ - cr = xspi->read_fn(xspi->regs + XSPI_CR_OFFSET) & - ~XSPI_CR_TRANS_INHIBIT; - xspi->write_fn(cr, xspi->regs + XSPI_CR_OFFSET); + for (;;) { + u16 cr; + u8 sr; - wait_for_completion(&xspi->done); + xilinx_spi_fill_tx_fifo(xspi); + + /* Start the transfer by not inhibiting the transmitter any + * longer + */ + cr = xspi->read_fn(xspi->regs + XSPI_CR_OFFSET) & + ~XSPI_CR_TRANS_INHIBIT; + xspi->write_fn(cr, xspi->regs + XSPI_CR_OFFSET); + + wait_for_completion(&xspi->done); + + /* A transmit has just completed. Process received data and + * check for more data to transmit. Always inhibit the + * transmitter while the Isr refills the transmit register/FIFO, + * or make sure it is stopped if we're done. + */ + cr = xspi->read_fn(xspi->regs + XSPI_CR_OFFSET); + xspi->write_fn(cr | XSPI_CR_TRANS_INHIBIT, + xspi->regs + XSPI_CR_OFFSET); + + /* Read out all the data from the Rx FIFO */ + sr = xspi->read_fn(xspi->regs + XSPI_SR_OFFSET); + while ((sr & XSPI_SR_RX_EMPTY_MASK) == 0) { + xspi->rx_fn(xspi); + sr = xspi->read_fn(xspi->regs + XSPI_SR_OFFSET); + } + + /* See if there is more data to send */ + if (xspi->remaining_bytes <= 0) + break; + } /* Disable the transmit empty interrupt */ xspi->write_fn(ipif_ier, xspi->regs + XIPIF_V123B_IIER_OFFSET); @@ -314,38 +326,7 @@ static irqreturn_t xilinx_spi_irq(int irq, void *dev_id) xspi->write_fn(ipif_isr, xspi->regs + XIPIF_V123B_IISR_OFFSET); if (ipif_isr & XSPI_INTR_TX_EMPTY) { /* Transmission completed */ - u16 cr; - u8 sr; - - /* A transmit has just completed. Process received data and - * check for more data to transmit. Always inhibit the - * transmitter while the Isr refills the transmit register/FIFO, - * or make sure it is stopped if we're done. - */ - cr = xspi->read_fn(xspi->regs + XSPI_CR_OFFSET); - xspi->write_fn(cr | XSPI_CR_TRANS_INHIBIT, - xspi->regs + XSPI_CR_OFFSET); - - /* Read out all the data from the Rx FIFO */ - sr = xspi->read_fn(xspi->regs + XSPI_SR_OFFSET); - while ((sr & XSPI_SR_RX_EMPTY_MASK) == 0) { - xspi->rx_fn(xspi); - sr = xspi->read_fn(xspi->regs + XSPI_SR_OFFSET); - } - - /* See if there is more data to send */ - if (xspi->remaining_bytes > 0) { - xilinx_spi_fill_tx_fifo(xspi); - /* Start the transfer by not inhibiting the - * transmitter any longer - */ - xspi->write_fn(cr, xspi->regs + XSPI_CR_OFFSET); - } else { - /* No more data to send. - * Indicate the transfer is completed. - */ - complete(&xspi->done); - } + complete(&xspi->done); } return IRQ_HANDLED; @@ -377,7 +358,6 @@ struct spi_master *xilinx_spi_init(struct device *dev, struct resource *mem, xspi->bitbang.chipselect = xilinx_spi_chipselect; xspi->bitbang.setup_transfer = xilinx_spi_setup_transfer; xspi->bitbang.txrx_bufs = xilinx_spi_txrx_bufs; - xspi->bitbang.master->setup = xilinx_spi_setup; init_completion(&xspi->done); if (!request_mem_region(mem->start, resource_size(mem), |