On Tue, 30 Aug 2022, Kumaravel Thiagarajan wrote:
> pci1xxxx is a PCIe switch with a multi-function endpoint on one of its
> downstream ports. Quad-uart is one of the functions in the
> multi-function endpoint. This driver loads for the quad-uart and
> enumerates single or multiple instances of uart based on the PCIe
> subsystem device ID.
>
> Signed-off-by: Kumaravel Thiagarajan <kumaravel.thiagarajan@xxxxxxxxxxxxx>
> ---
> +static int mchp_pci1xxxx_rs485_config(struct uart_port *port,
> + struct ktermios *termios,
> + struct serial_rs485 *rs485)
> +{
> + u8 data = 0;
> +
> + memset(rs485->padding, 0, sizeof(rs485->padding));
> + rs485->flags &= SER_RS485_ENABLED | SER_RS485_RTS_ON_SEND;
> +
> + 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;
> + rs485->flags |= SER_RS485_RTS_AFTER_SEND;
> + }
> + }
> +
> + rs485->delay_rts_after_send = 0;
> + rs485->delay_rts_before_send = 0;
> + writeb(data, (port->membase + ADCL_CFG_REG));
> + port->rs485 = *rs485;
Most of this will be handled for by the core so don't duplicate it in
the driver.
These days, you also need to provide rs485_supported.
> + return 0;
> +}
> +
> +static void mchp_pci1xxxx_set_termios(struct uart_port *port,
> + struct ktermios *termios,
> + struct ktermios *old)
> +{
> + const unsigned int standard_baud_list[] = {50, 75, 110, 134, 150, 300,
> + 600, 1200, 1800, 2000, 2400, 3600,
> + 4800, 7200, 9600, 19200, 38400, 57600,
> + 115200, 125000, 136400, 150000, 166700,
> + 187500, 214300, 250000, 300000, 375000,
> + 500000, 750000, 1000000, 1500000};
> + unsigned int baud = tty_termios_baud_rate(termios);
> + unsigned int baud_clock;
> + unsigned int quot;
> + unsigned int frac;
> + unsigned int i;
> +
> + baud = tty_termios_baud_rate(termios);
Either this or the one at the declaration is redundant.
> + serial8250_do_set_termios(port, termios, NULL);
> +
> + if (baud == 38400 && (port->flags & UPF_SPD_MASK) == UPF_SPD_CUST) {
> + writel((port->custom_divisor & 0x3FFFFFFF),
> + (port->membase + CLK_DIVISOR_REG));
> + } else {
> + for (i = 0; i < ARRAY_SIZE(standard_baud_list); i++) {
> + if (baud == standard_baud_list[i])
> + return;
Did you mean to break here instead?
> + }
> + tty_termios_encode_baud_rate(termios, baud, baud);
> +
> + baud = uart_get_baud_rate(port, termios, old,
> + 50, 1500000);
> + baud_clock = readb(port->membase + CLK_SEL_REG);
> +
> + if ((baud_clock & CLK_SEL_MASK) == CLK_SEL_500MHZ) {
> + quot = 500000000 / (16 * baud);
> + writel(quot, (port->membase + CLK_DIVISOR_REG));
> + } else if ((baud_clock & CLK_SEL_MASK) == CLK_SEL_166MHZ) {
> + quot = (166667 * 1000) / (16 * baud);
> + writel(quot, (port->membase + CLK_DIVISOR_REG));
> + } else {
> + quot = ((1000000000) / (baud * UART_BIT_SAMPLE_CNT));
> + frac = (((1000000000 - (quot * baud *
> + UART_BIT_SAMPLE_CNT)) / UART_BIT_SAMPLE_CNT)
> + * 255) / baud;
> + writel(frac | (quot << 8),
> + (port->membase + CLK_DIVISOR_REG));
> + }
Please check ->[gs]et_divisor() out.
--
i.
