diff options
| author | David Jander <david@protonic.nl> | 2015-06-26 08:11:30 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2015-07-23 17:40:14 -0700 |
| commit | 907eda32a36fcdb979bdb91ea097abb3dd2c23c9 (patch) | |
| tree | 0439183b86525692aff77c3894135250c7ece978 /drivers/tty | |
| parent | dec273ecc1169ade46999bb0feca3814915f5c11 (diff) | |
| download | linux-907eda32a36fcdb979bdb91ea097abb3dd2c23c9.tar.bz2 | |
Revert "serial: imx: initialized DMA w/o HW flow enabled"
This reverts commit 068500e08dc87ea9a453cc4a500cf3ab28d0f936.
According to some tests, SDMA support is broken at least for i.MX6 without
HW flow control. Different forms of data-corruption appear either with
the ROM firmware for the SDMA controller as well as when loading Freescale
provided SDMA firmware versions 1.1 or 3.1.
Signed-off-by: David Jander <david@protonic.nl>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/tty')
| -rw-r--r-- | drivers/tty/serial/imx.c | 15 |
1 files changed, 7 insertions, 8 deletions
diff --git a/drivers/tty/serial/imx.c b/drivers/tty/serial/imx.c index 2c90dc31bfaa..54fdc7866ea1 100644 --- a/drivers/tty/serial/imx.c +++ b/drivers/tty/serial/imx.c @@ -1121,11 +1121,6 @@ static int imx_startup(struct uart_port *port) writel(temp & ~UCR4_DREN, sport->port.membase + UCR4); - /* Can we enable the DMA support? */ - if (is_imx6q_uart(sport) && !uart_console(port) && - !sport->dma_is_inited) - imx_uart_dma_init(sport); - spin_lock_irqsave(&sport->port.lock, flags); /* Reset fifo's and state machines */ i = 100; @@ -1143,9 +1138,6 @@ static int imx_startup(struct uart_port *port) writel(USR1_RTSD, sport->port.membase + USR1); writel(USR2_ORE, sport->port.membase + USR2); - if (sport->dma_is_inited && !sport->dma_is_enabled) - imx_enable_dma(sport); - temp = readl(sport->port.membase + UCR1); temp |= UCR1_RRDYEN | UCR1_RTSDEN | UCR1_UARTEN; @@ -1316,6 +1308,11 @@ imx_set_termios(struct uart_port *port, struct ktermios *termios, } else { ucr2 |= UCR2_CTSC; } + + /* Can we enable the DMA support? */ + if (is_imx6q_uart(sport) && !uart_console(port) + && !sport->dma_is_inited) + imx_uart_dma_init(sport); } else { termios->c_cflag &= ~CRTSCTS; } @@ -1432,6 +1429,8 @@ imx_set_termios(struct uart_port *port, struct ktermios *termios, if (UART_ENABLE_MS(&sport->port, termios->c_cflag)) imx_enable_ms(&sport->port); + if (sport->dma_is_inited && !sport->dma_is_enabled) + imx_enable_dma(sport); spin_unlock_irqrestore(&sport->port.lock, flags); } |