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;
u32 cr;
int len = 0;
cr = spi_regr(xspi, XSPI_CR_OFFSET);
if (cr & XSPI_CR_MASTER_MODE) { /* We're a SPI master */
/* We get here with transmitter inhibited */
xspi->tx_ptr = t->tx_buf;
xspi->remaining_bytes = t->len;
xspi->rx_ptr = t->rx_buf;
INIT_COMPLETION(xspi->done);
xilinx_spi_fill_tx_fifo(xspi);
/* Enable the transmit empty interrupt, which we use to determine
* progress on the transmission.
*/
ipif_ier = spi_regr(xspi, XIPIF_V123B_IIER_OFFSET);
spi_regw(xspi, XIPIF_V123B_IIER_OFFSET, ipif_ier | XSPI_INTR_TX_EMPTY);
/* Start the transfer by not inhibiting the transmitter any longer */
spi_regw(xspi, XSPI_CR_OFFSET, cr & ~XSPI_CR_TRANS_INHIBIT);
wait_for_completion(&xspi->done);
/* Disable the interrupt */
spi_regw(xspi, XIPIF_V123B_IIER_OFFSET, ipif_ier);
len = t->len - xspi->remaining_bytes;
} else { /* We're a SPI slave */
if (t->tx_buf != NULL) {
/* Make a local copy of the data to transmit, since we can't be sure the
* caller's buffer will still be around when the transfer occurs.
*/
len = min((size_t)t->len, sizeof(xspi->slave_tx_buf));
memcpy(xspi->slave_tx_buf, t->tx_buf, len);
xspi->tx_ptr = xspi->slave_tx_buf;
xspi->remaining_bytes = len;
xspi->tx_len = len;
/* Clear out old transmit contents */
spi_regw(xspi, XSPI_CR_OFFSET, cr | XSPI_CR_TXFIFO_RESET);
xilinx_spi_fill_tx_fifo(xspi);
}
if (t->rx_buf != NULL) {
len = min((int)t->len, (int)(xspi->rx_ptr - xspi->slave_rx_buf));
/* Clear out old receive contents */
spi_regw(xspi, XSPI_CR_OFFSET, cr | XSPI_CR_RXFIFO_RESET);
memcpy(t->rx_buf, xspi->slave_rx_buf, len);
if (len < xspi->rx_ptr - xspi->slave_rx_buf) {
memcpy(xspi->slave_rx_buf, xspi->slave_rx_buf + len,
(xspi->rx_ptr - xspi->slave_rx_buf) - len);
}
xspi->rx_ptr -= len;
}
}
return len;
}
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 */
xspi->tx_ptr = t->tx_buf;
xspi->rx_ptr = t->rx_buf;
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.
*/
ipif_ier = xspi->read_fn(xspi->regs + XIPIF_V123B_IIER_OFFSET);
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);
wait_for_completion(&xspi->done);
/* Disable the transmit empty interrupt */
xspi->write_fn(ipif_ier, xspi->regs + XIPIF_V123B_IIER_OFFSET);
return t->len - xspi->remaining_bytes;
}
static irqreturn_t xilinx_spi_irq(int irq, void *dev_id)
{
struct xilinx_spi *xspi = dev_id;
u32 ipif_isr;
ipif_isr = xspi->read_fn(xspi->regs + XIPIF_V123B_IISR_OFFSET);
xspi->write_fn(ipif_isr, xspi->regs + XIPIF_V123B_IISR_OFFSET);
if (ipif_isr & XSPI_INTR_TX_EMPTY) {
u16 cr;
u8 sr;
cr = xspi->read_fn(xspi->regs + XSPI_CR_OFFSET);
xspi->write_fn(cr | XSPI_CR_TRANS_INHIBIT,
xspi->regs + XSPI_CR_OFFSET);
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);
}
if (xspi->remaining_bytes > 0) {
xilinx_spi_fill_tx_fifo(xspi);
xspi->write_fn(cr, xspi->regs + XSPI_CR_OFFSET);
} else {
complete(&xspi->done);
}
}
return IRQ_HANDLED;
}
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;
xspi->tx_ptr = t->tx_buf;
xspi->rx_ptr = t->rx_buf;
xspi->remaining_bytes = t->len;
INIT_COMPLETION(xspi->done);
xilinx_spi_fill_tx_fifo(xspi);
ipif_ier = xspi->read_fn(xspi->regs + XIPIF_V123B_IIER_OFFSET);
xspi->write_fn(ipif_ier | XSPI_INTR_TX_EMPTY,
xspi->regs + XIPIF_V123B_IIER_OFFSET);
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);
xspi->write_fn(ipif_ier, xspi->regs + XIPIF_V123B_IIER_OFFSET);
return t->len - xspi->remaining_bytes;
}
static void xspi_reset_transmit_buffer(struct xilinx_spi *xspi)
{
xspi->tx_ptr = xspi->slave_tx_buf;
xspi->remaining_bytes = xspi->tx_len;
/* Clear out old transmit contents */
spi_regw(xspi, XSPI_CR_OFFSET, spi_regr(xspi, XSPI_CR_OFFSET) | XSPI_CR_TXFIFO_RESET);
xilinx_spi_fill_tx_fifo(xspi);
}
/* This driver supports single master mode only. Hence Tx FIFO Empty
* is the only interrupt we care about.
* Receive FIFO Overrun, Transmit FIFO Underrun, Mode Fault, and Slave Mode
* Fault are not to happen.
*/
static irqreturn_t xilinx_spi_irq(int irq, void *dev_id)
{
struct xilinx_spi *xspi = dev_id;
u32 ipif_isr;
/* Get the IPIF interrupts, and clear them immediately */
ipif_isr = in_be32(xspi->regs + XIPIF_V123B_IISR_OFFSET);
out_be32(xspi->regs + XIPIF_V123B_IISR_OFFSET, ipif_isr);
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 = in_be16(xspi->regs + XSPI_CR_OFFSET);
out_be16(xspi->regs + XSPI_CR_OFFSET,
cr | XSPI_CR_TRANS_INHIBIT);
/* Read out all the data from the Rx FIFO */
sr = in_8(xspi->regs + XSPI_SR_OFFSET);
while ((sr & XSPI_SR_RX_EMPTY_MASK) == 0) {
u8 data;
data = in_8(xspi->regs + XSPI_RXD_OFFSET);
if (xspi->rx_ptr) {
*xspi->rx_ptr++ = data;
}
sr = in_8(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
*/
out_be16(xspi->regs + XSPI_CR_OFFSET, cr);
} else {
/* No more data to send.
* Indicate the transfer is completed.
*/
complete(&xspi->done);
}
}
return IRQ_HANDLED;
}
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;
/* We get here with transmitter inhibited */
xspi->tx_ptr = t->tx_buf;
xspi->rx_ptr = t->rx_buf;
xspi->remaining_bytes = t->len;
reinit_completion(&xspi->done);
/* Enable the transmit empty interrupt, which we use to determine
* progress on the transmission.
*/
ipif_ier = xspi->read_fn(xspi->regs + XIPIF_V123B_IIER_OFFSET);
xspi->write_fn(ipif_ier | XSPI_INTR_TX_EMPTY,
xspi->regs + XIPIF_V123B_IIER_OFFSET);
for (;;) {
u16 cr;
u8 sr;
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);
return t->len - xspi->remaining_bytes;
}
/* In single master mode, Tx FIFO Empty is the only interrupt we care about.
* As a slave, Receive FIFO Not Empty and (possibly) Slave Sel Asserted interrupts used.
* Receive FIFO Overrun, Transmit FIFO Underrun, Mode Fault, and Slave Mode
* Fault are not to happen.
*/
static irqreturn_t xilinx_spi_irq(int irq, void *dev_id)
{
struct xilinx_spi *xspi = dev_id;
u32 ipif_isr;
u32 cr;
u32 sr;
/* Get the IPIF interrupts, and clear them immediately */
ipif_isr = spi_regr(xspi, XIPIF_V123B_IISR_OFFSET);
spi_regw(xspi, XIPIF_V123B_IISR_OFFSET, ipif_isr);
cr = spi_regr(xspi, XSPI_CR_OFFSET);
if (cr & XSPI_CR_MASTER_MODE) { /* We're a SPI master */
if (ipif_isr & XSPI_INTR_TX_EMPTY) { /* Transmission completed */
/* 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.
*/
spi_regw(xspi, XSPI_CR_OFFSET, cr | XSPI_CR_TRANS_INHIBIT);
/* Read out all the data from the Rx FIFO */
sr = spi_regr(xspi, XSPI_SR_OFFSET);
while ((sr & XSPI_SR_RX_EMPTY_MASK) == 0) {
u32 data;
data = spi_regr(xspi, XSPI_RXD_OFFSET);
#ifdef XSPI_DEBUG_FIFOIO
printk("<%02x>", data & 0xff);
#endif
if (xspi->rx_ptr) {
*xspi->rx_ptr++ = (u8)(data & 0xFF);
}
sr = spi_regr(xspi, 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
*/
spi_regw(xspi, XSPI_CR_OFFSET, cr);
} else {
/* No more data to send.
* Indicate the transfer is completed.
*/
complete(&xspi->done);
}
}
} else { /* We're a SPI slave */
if (ipif_isr & XSPI_INTR_SLAVE_SEL_ASSERT) {
xspi_reset_transmit_buffer(xspi);
}
if (ipif_isr & XSPI_INTR_RX_NOT_EMPTY) { /* Byte received */
/* Read out all the data from the Rx FIFO */
sr = spi_regr(xspi, XSPI_SR_OFFSET);
while ((sr & XSPI_SR_RX_EMPTY_MASK) == 0) {
u32 data;
data = spi_regr(xspi, XSPI_RXD_OFFSET);
#ifdef XSPI_DEBUG_FIFOIO
printk("{%02x}", data & 0xff);
#endif
if (xspi->rx_ptr - xspi->slave_rx_buf < sizeof(xspi->slave_rx_buf)) {
*xspi->rx_ptr++ = (u8)(data & 0xFF);
}
/* Check if the transfer is completed. */
sr = spi_regr(xspi, XSPI_SR_OFFSET);
}
if (xspi->remaining_bytes > 0) {
xilinx_spi_fill_tx_fifo(xspi);
}
}
}
return IRQ_HANDLED;
}