[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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