serial: 8250: Add support for dmaengine
Add support for dmaengine API. The drivers can implement the
struct uart_8250_dma member in struct uart_8250_port and
8250.c can take care of the rest.
Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/tty/serial/8250/8250.h b/drivers/tty/serial/8250/8250.h
index 3b4ea84..363d549 100644
--- a/drivers/tty/serial/8250/8250.h
+++ b/drivers/tty/serial/8250/8250.h
@@ -12,6 +12,35 @@
*/
#include <linux/serial_8250.h>
+#include <linux/dmaengine.h>
+
+struct uart_8250_dma {
+ dma_filter_fn fn;
+ void *rx_param;
+ void *tx_param;
+
+ int rx_chan_id;
+ int tx_chan_id;
+
+ struct dma_slave_config rxconf;
+ struct dma_slave_config txconf;
+
+ struct dma_chan *rxchan;
+ struct dma_chan *txchan;
+
+ dma_addr_t rx_addr;
+ dma_addr_t tx_addr;
+
+ dma_cookie_t rx_cookie;
+ dma_cookie_t tx_cookie;
+
+ void *rx_buf;
+
+ size_t rx_size;
+ size_t tx_size;
+
+ unsigned char tx_running:1;
+};
struct old_serial_port {
unsigned int uart;
@@ -142,3 +171,24 @@
return 0;
}
#endif
+
+#ifdef CONFIG_SERIAL_8250_DMA
+extern int serial8250_tx_dma(struct uart_8250_port *);
+extern int serial8250_rx_dma(struct uart_8250_port *, unsigned int iir);
+extern int serial8250_request_dma(struct uart_8250_port *);
+extern void serial8250_release_dma(struct uart_8250_port *);
+#else
+static inline int serial8250_tx_dma(struct uart_8250_port *p)
+{
+ return -1;
+}
+static inline int serial8250_rx_dma(struct uart_8250_port *p, unsigned int iir)
+{
+ return -1;
+}
+static inline int serial8250_request_dma(struct uart_8250_port *p)
+{
+ return -1;
+}
+static inline void serial8250_release_dma(struct uart_8250_port *p) { }
+#endif