From f1a297bb044265efafd9b941d00d52cb66835695 Mon Sep 17 00:00:00 2001 From: Sebastian Andrzej Siewior Date: Mon, 29 Sep 2014 20:06:42 +0200 Subject: [PATCH] tty: serial: 8250: allow to use custom DMA implementation The OMAP has a few corner cases where it needs a share of kindness of affection to do the right thing. Heikki Krogerus suggested that instead adding the quirks into the default DMA implementation, OMAP could get its own copy of the function. And Alan suggested the same thing so here we go. This patch provides callbacks for custom TX/RX DMA implementation. If there are not setup / used, then the default (current) implementation is used. Signed-off-by: Sebastian Andrzej Siewior Reviewed-by: Peter Hurley Signed-off-by: Greg Kroah-Hartman --- drivers/tty/serial/8250/8250.h | 3 +++ drivers/tty/serial/8250/8250_core.c | 11 ++++++++--- drivers/tty/serial/8250/8250_dma.c | 2 -- 3 files changed, 11 insertions(+), 5 deletions(-) diff --git a/drivers/tty/serial/8250/8250.h b/drivers/tty/serial/8250/8250.h index 712d1600c206..0dc1cb6b2706 100644 --- a/drivers/tty/serial/8250/8250.h +++ b/drivers/tty/serial/8250/8250.h @@ -16,6 +16,9 @@ #include struct uart_8250_dma { + int (*tx_dma)(struct uart_8250_port *p); + int (*rx_dma)(struct uart_8250_port *p, unsigned int iir); + /* Filter function */ dma_filter_fn fn; diff --git a/drivers/tty/serial/8250/8250_core.c b/drivers/tty/serial/8250/8250_core.c index f0f31d28b2f5..39450ba03a2f 100644 --- a/drivers/tty/serial/8250/8250_core.c +++ b/drivers/tty/serial/8250/8250_core.c @@ -1353,7 +1353,7 @@ static void serial8250_start_tx(struct uart_port *port) struct uart_8250_port *up = up_to_u8250p(port); serial8250_rpm_get_tx(up); - if (up->dma && !serial8250_tx_dma(up)) { + if (up->dma && !up->dma->tx_dma(up)) { return; } else if (!(up->ier & UART_IER_THRI)) { up->ier |= UART_IER_THRI; @@ -1591,7 +1591,7 @@ int serial8250_handle_irq(struct uart_port *port, unsigned int iir) if (status & (UART_LSR_DR | UART_LSR_BI)) { if (up->dma) - dma_err = serial8250_rx_dma(up, iir); + dma_err = up->dma->rx_dma(up, iir); if (!up->dma || dma_err) status = serial8250_rx_chars(up, status); @@ -3627,8 +3627,13 @@ int serial8250_register_8250_port(struct uart_8250_port *up) uart->dl_read = up->dl_read; if (up->dl_write) uart->dl_write = up->dl_write; - if (up->dma) + if (up->dma) { uart->dma = up->dma; + if (!uart->dma->tx_dma) + uart->dma->tx_dma = serial8250_tx_dma; + if (!uart->dma->rx_dma) + uart->dma->rx_dma = serial8250_rx_dma; + } if (serial8250_isa_config != NULL) serial8250_isa_config(0, &uart->port, diff --git a/drivers/tty/serial/8250/8250_dma.c b/drivers/tty/serial/8250/8250_dma.c index db9eda3c12d6..258430b72039 100644 --- a/drivers/tty/serial/8250/8250_dma.c +++ b/drivers/tty/serial/8250/8250_dma.c @@ -118,7 +118,6 @@ err: dma->tx_err = 1; return ret; } -EXPORT_SYMBOL_GPL(serial8250_tx_dma); int serial8250_rx_dma(struct uart_8250_port *p, unsigned int iir) { @@ -165,7 +164,6 @@ int serial8250_rx_dma(struct uart_8250_port *p, unsigned int iir) return 0; } -EXPORT_SYMBOL_GPL(serial8250_rx_dma); int serial8250_request_dma(struct uart_8250_port *p) { -- 2.20.1