On Fri, Nov 11, 2022 at 09:41:29PM +0530, Kumaravel Thiagarajan wrote:
> pci1xxxx uart supports rs485 mode of operation in the hardware with
UART
RS485 (same in the subject)
> auto-direction control with configurable delay for releasing RTS after
> the transmission. This patch adds support for the rs485 mode.
RS485
...
> Signed-off-by: Tharun Kumar P <tharunkumar.pasumarthi@xxxxxxxxxxxxx>
> Signed-off-by: Kumaravel Thiagarajan <kumaravel.thiagarajan@xxxxxxxxxxxxx>
No Co-developed-by?
...
> +static int pci1xxxx_rs485_config(struct uart_port *port,
> + struct ktermios *termios,
> + struct serial_rs485 *rs485)
> +{
> + u32 clock_div = readl(port->membase + UART_BAUD_CLK_DIVISOR_REG);
> + u8 delay_in_baud_periods = 0;
> + u32 baud_period_in_ns = 0;
Why these assignments?
> + u32 data = 0;
> +
> + /* pci1xxxx's uart hardware supports only RTS delay after
> + * Tx and in units of bit times to a maximum of 15
> + */
/*
* Use proper multi-line
* comment style.
*/
> + if (rs485->flags & SER_RS485_ENABLED) {
> + data = ADCL_CFG_EN | ADCL_CFG_PIN_SEL;
> +
> + if (!(rs485->flags & SER_RS485_RTS_ON_SEND))
> + data |= ADCL_CFG_POL_SEL;
> +
> + if (rs485->delay_rts_after_send) {
> + baud_period_in_ns =
> + FIELD_GET(BAUD_CLOCK_DIV_INT_MSK, clock_div) *
> + UART_BIT_SAMPLE_CNT;
> + delay_in_baud_periods =
> + (rs485->delay_rts_after_send * NSEC_PER_MSEC) /
> + baud_period_in_ns;
> + delay_in_baud_periods =
> + min_t(u8, delay_in_baud_periods,
> + FIELD_MAX(ADCL_CFG_RTS_DELAY_MASK));
> + data |= FIELD_PREP(ADCL_CFG_RTS_DELAY_MASK,
> + delay_in_baud_periods);
> + rs485->delay_rts_after_send =
> + (baud_period_in_ns * delay_in_baud_periods) /
> + NSEC_PER_MSEC;
> + rs485->delay_rts_before_send = 0;
> + }
> + }
> + writel(data, port->membase + ADCL_CFG_REG);
> + return 0;
> +}
--
With Best Regards,
Andy Shevchenko
