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Commit d1834bab authored by Andy Shevchenko's avatar Andy Shevchenko Committed by Greg Kroah-Hartman
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serial: 8250_dma: adjust DMA address of the UART 



Some UARTs, e.g. one is used in Intel Quark, have a different address base for
DMA operations. Introduce an additional field (per RX and TX DMA channels) in
struct uart_8250_dma to cover those cases.

Reviewed-by: default avatarHeikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: default avatarAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Tested-by: default avatarBryan O'Donoghue <pure.logic@nexus-software.ie>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 8d170472

drivers/tty/serial/8250/8250.h

+5 −0
Original line number Diff line number Diff line
@@ -33,6 +33,11 @@ struct uart_8250_dma { 
	struct dma_chan		*rxchan;

	struct dma_chan		*txchan;



	/* Device address base for DMA operations */

	phys_addr_t		rx_dma_addr;

	phys_addr_t		tx_dma_addr;



	/* DMA address of the buffer in memory */

	dma_addr_t		rx_addr;

	dma_addr_t		tx_addr;

drivers/tty/serial/8250/8250_dma.c

+6 −2
Original line number Diff line number Diff line
@@ -150,6 +150,10 @@ EXPORT_SYMBOL_GPL(serial8250_rx_dma_flush); 
int serial8250_request_dma(struct uart_8250_port *p)

{

	struct uart_8250_dma	*dma = p->dma;

	phys_addr_t rx_dma_addr = dma->rx_dma_addr ?

				  dma->rx_dma_addr : p->port.mapbase;

	phys_addr_t tx_dma_addr = dma->tx_dma_addr ?

				  dma->tx_dma_addr : p->port.mapbase;

	dma_cap_mask_t		mask;

	struct dma_slave_caps	caps;

	int			ret;
@@ -157,11 +161,11 @@ int serial8250_request_dma(struct uart_8250_port *p) 
	/* Default slave configuration parameters */

	dma->rxconf.direction		= DMA_DEV_TO_MEM;

	dma->rxconf.src_addr_width	= DMA_SLAVE_BUSWIDTH_1_BYTE;

	dma->rxconf.src_addr		= p->port.mapbase + UART_RX;

	dma->rxconf.src_addr		= rx_dma_addr + UART_RX;



	dma->txconf.direction		= DMA_MEM_TO_DEV;

	dma->txconf.dst_addr_width	= DMA_SLAVE_BUSWIDTH_1_BYTE;

	dma->txconf.dst_addr		= p->port.mapbase + UART_TX;

	dma->txconf.dst_addr		= tx_dma_addr + UART_TX;



	dma_cap_zero(mask);

	dma_cap_set(DMA_SLAVE, mask);