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serial: imx: simplify tracking of dma being initialized 

The .dma_is_inited member is only set to a value != 0 when the port's
startup function calls imx_uart_dma_init(). On shutdown of the port
imx_uart_dma_exit is called which sets the value back to 0. So
.dma_is_inited is always 0 when imx_startup() is called (assuming
.startup() and .shutdown() are correctly balanced) and the check for
!sport->dma_is_inited can go away.

This allows to replace .dma_is_inited by a variable local to
imx_startup.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Reviewed-by: Shawn Guo <shawnguo@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Uwe Kleine-König 2018-02-18 22:02:45 +01:00 committed by Greg Kroah-Hartman
parent 437768962f
commit 4238c00bb1
1 changed files with 4 additions and 8 deletions
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12
drivers/tty/serial/imx.c
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@ -205,7 +205,6 @@ struct imx_port {
struct mctrl_gpios *gpios;
/* DMA fields */
unsigned int dma_is_inited:1;
unsigned int dma_is_enabled:1;
unsigned int dma_is_rxing:1;
unsigned int dma_is_txing:1;
@ -1114,8 +1113,6 @@ static void imx_uart_dma_exit(struct imx_port *sport)
dma_release_channel(sport->dma_chan_tx);
sport->dma_chan_tx = NULL;
}
sport->dma_is_inited = 0;
}
static int imx_uart_dma_init(struct imx_port *sport)
@ -1168,8 +1165,6 @@ static int imx_uart_dma_init(struct imx_port *sport)
goto err;
}
sport->dma_is_inited = 1;
return 0;
err:
imx_uart_dma_exit(sport);
@ -1217,6 +1212,7 @@ static int imx_startup(struct uart_port *port)
struct imx_port *sport = (struct imx_port *)port;
int retval, i;
unsigned long flags, temp;
int dma_is_inited = 0;
retval = clk_prepare_enable(sport->clk_per);
if (retval)
@ -1241,8 +1237,8 @@ static int imx_startup(struct uart_port *port)
writel(temp & ~UCR4_DREN, sport->port.membase + UCR4);
/* Can we enable the DMA support? */
if (!uart_console(port) && !sport->dma_is_inited)
imx_uart_dma_init(sport);
if (!uart_console(port) && imx_uart_dma_init(sport) == 0)
dma_is_inited = 1;
spin_lock_irqsave(&sport->port.lock, flags);
/* Reset fifo's and state machines */
@ -1261,7 +1257,7 @@ static int imx_startup(struct uart_port *port)
writel(USR1_RTSD | USR1_DTRD, sport->port.membase + USR1);
writel(USR2_ORE, sport->port.membase + USR2);
if (sport->dma_is_inited && !sport->dma_is_enabled)
if (dma_is_inited && !sport->dma_is_enabled)
imx_enable_dma(sport);
temp = readl(sport->port.membase + UCR1) & ~UCR1_RRDYEN;