On Thu, Jan 07, 2021 at 02:16:41PM +0800, zhangqiumiao1@xxxxxxxxxx wrote:
> From: Qiumiao Zhang <zhangqiumiao1@xxxxxxxxxx>
>
> make pl011 serial port support 485 mode full duplex communication
>
> Signed-off-by: Qiumiao Zhang <zhangqiumiao1@xxxxxxxxxx>
> ---
> Changes in v2:
> - Fix two compilation errors
What changed from the version you sent yesterday with this same subject
line?
> drivers/tty/serial/amba-pl011.c | 38 +++++++++++++++++++++++++++++++++
> 1 file changed, 38 insertions(+)
>
> diff --git a/drivers/tty/serial/amba-pl011.c b/drivers/tty/serial/amba-pl011.c
> index c255476cce28..f6a7fe61e699 100644
> --- a/drivers/tty/serial/amba-pl011.c
> +++ b/drivers/tty/serial/amba-pl011.c
> @@ -44,6 +44,7 @@
>
> #include "amba-pl011.h"
>
> +#define ISEMPTY 1
> #define UART_NR 14
>
> #define SERIAL_AMBA_MAJOR 204
> @@ -1284,14 +1285,33 @@ static inline bool pl011_dma_rx_running(struct uart_amba_port *uap)
> #define pl011_dma_flush_buffer NULL
> #endif
>
> +static unsigned int pl011_tx_empty(struct uart_port *port);
> +
> static void pl011_stop_tx(struct uart_port *port)
> {
> + unsigned int cr;
> + unsigned int result;
But below the uap definition please, like kernel style normally is.
> struct uart_amba_port *uap =
> container_of(port, struct uart_amba_port, port);
>
> uap->im &= ~UART011_TXIM;
> pl011_write(uap->im, uap, REG_IMSC);
> pl011_dma_tx_stop(uap);
> + if (port->rs485.flags & SER_RS485_ENABLED) {
> + while(1) {
> + result = pl011_tx_empty(port);
> + if (ISEMPTY == result) {
> + break;
> + }
It's not ok to busy loop forever, sorry.
> + }
> + cr = pl011_read(uap, REG_CR);
> + if (port->rs485.flags & SER_RS485_RTS_AFTER_SEND) {
> + cr |= UART011_CR_RTS;
> + } else {
> + cr &= ~UART011_CR_RTS;
> + }
Did you run checkpatch on this code? Please fix up.
thanks,
greg k-h
