From: Sascha Hauer Fix occasional tx buffer overflows in the i.MX serial driver which came from the fact that space in the buffer was checked after sending the first byte. Also, fifosize is 32 bytes, not 8. Signed-off-by: Sascha Hauer Acked-by: Pavel Pisa Signed-off-by: Andrew Morton --- drivers/serial/imx.c | 11 +++++------ 1 files changed, 5 insertions(+), 6 deletions(-) diff -puN drivers/serial/imx.c~arm-imx-serial-fix-tx-buffer-overflows drivers/serial/imx.c --- a/drivers/serial/imx.c~arm-imx-serial-fix-tx-buffer-overflows +++ a/drivers/serial/imx.c @@ -154,7 +154,7 @@ static inline void imx_transmit_buffer(s { struct circ_buf *xmit = &sport->port.info->xmit; - do { + while (!(UTS((u32)sport->port.membase) & UTS_TXFULL)) { /* send xmit->buf[xmit->tail] * out the port here */ URTX0((u32)sport->port.membase) = xmit->buf[xmit->tail]; @@ -163,7 +163,7 @@ static inline void imx_transmit_buffer(s sport->port.icount.tx++; if (uart_circ_empty(xmit)) break; - } while (!(UTS((u32)sport->port.membase) & UTS_TXFULL)); + } if (uart_circ_empty(xmit)) imx_stop_tx(&sport->port); @@ -178,8 +178,7 @@ static void imx_start_tx(struct uart_por UCR1((u32)sport->port.membase) |= UCR1_TXMPTYEN; - if(UTS((u32)sport->port.membase) & UTS_TXEMPTY) - imx_transmit_buffer(sport); + imx_transmit_buffer(sport); } static irqreturn_t imx_rtsint(int irq, void *dev_id) @@ -678,7 +677,7 @@ static struct imx_port imx_ports[] = { .mapbase = IMX_UART1_BASE, /* FIXME */ .irq = UART1_MINT_RX, .uartclk = 16000000, - .fifosize = 8, + .fifosize = 32, .flags = UPF_BOOT_AUTOCONF, .ops = &imx_pops, .line = 0, @@ -694,7 +693,7 @@ static struct imx_port imx_ports[] = { .mapbase = IMX_UART2_BASE, /* FIXME */ .irq = UART2_MINT_RX, .uartclk = 16000000, - .fifosize = 8, + .fifosize = 32, .flags = UPF_BOOT_AUTOCONF, .ops = &imx_pops, .line = 1, _