[PATCH v2 2/9] serial: bflb_uart: add Bouffalolab UART Driver
Jiri Slaby
jirislaby at kernel.org
Sun Nov 27 22:10:41 PST 2022
On 27. 11. 22, 14:24, Jisheng Zhang wrote:
> +static void bflb_uart_tx_chars(struct uart_port *port)
Again:
Are you unable to use the TX helper? If so:
* why?
* use uart_advance_xmit() at least.
> +{
> + struct circ_buf *xmit = &port->state->xmit;
> + unsigned int count;
> +
> + if (port->x_char) {
> + /* Send special char - probably flow control */
> + wrl(port, UART_FIFO_WDATA, port->x_char);
> + port->x_char = 0;
> + port->icount.tx++;
> + return;
> + }
> +
> + if (uart_circ_empty(xmit) || uart_tx_stopped(port)) {
> + bflb_uart_stop_tx(port);
> + return;
> + }
> +
> + count = BFLB_UART_TX_FIFO_TH;
> + do {
> + wrl(port, UART_FIFO_WDATA, xmit->buf[xmit->tail]);
> + xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
> + port->icount.tx++;
> + if (uart_circ_empty(xmit))
> + break;
> + } while (--count > 0);
> +
> + if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
> + uart_write_wakeup(port);
> +
> + if (uart_circ_empty(xmit))
> + bflb_uart_stop_tx(port);
> +}
--
js
suse labs
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