diff options
| author | Andy Shevchenko <andriy.shevchenko@linux.intel.com> | 2016-08-17 19:20:25 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2016-08-31 16:13:29 +0200 |
| commit | d1834babe42246bf0bd0989b8bb19c9807851527 (patch) | |
| tree | 9cec0a0dc9bdd909da47c8539eff58f0e94ed1be /drivers/tty | |
| parent | 8d17047207d52182ccd55b9529e1c8cc062c07c2 (diff) | |
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: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Tested-by: Bryan O'Donoghue <pure.logic@nexus-software.ie>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/tty')
| -rw-r--r-- | drivers/tty/serial/8250/8250.h | 5 | ||||
| -rw-r--r-- | drivers/tty/serial/8250/8250_dma.c | 8 |
2 files changed, 11 insertions, 2 deletions
diff --git a/drivers/tty/serial/8250/8250.h b/drivers/tty/serial/8250/8250.h index 122e0e4029fe..c807b7393d4a 100644 --- a/drivers/tty/serial/8250/8250.h +++ b/drivers/tty/serial/8250/8250.h @@ -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; diff --git a/drivers/tty/serial/8250/8250_dma.c b/drivers/tty/serial/8250/8250_dma.c index 896e8f49b6f7..fdbddbc6375d 100644 --- a/drivers/tty/serial/8250/8250_dma.c +++ b/drivers/tty/serial/8250/8250_dma.c @@ -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); |