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SubjectRe: [PATCH] atmel_serial: Atmel RS485 support v2
NAK - assorted problems, notably locking ones caused by the sysfs stuff
which should probably be dropped.

> +#define TIOCSRS485 0x5461

Please provide TIOCGRS485 as well



> +static ssize_t show_rs485(struct device *dev, struct device_attribute *attr,
> + char *buf)
> +{
> + struct platform_device *pdev = to_platform_device(dev);
> + struct uart_port *port = platform_get_drvdata(pdev);
> + unsigned int current_mode;
> +
> + current_mode = UART_GET_MR(port) & ATMEL_US_USMODE;
> + return snprintf(buf, PAGE_SIZE, "%u\n", current_mode);
> +}

You should have TIOCGRS485 for providing the info back as part of the API

> +
> +static ssize_t set_rs485(struct device *dev, struct device_attribute *attr,
> + const char *buf, size_t len)

Expain the locking on this could you - I don't see what protects against
parallel ioctl and sysfs stuff ?

> +static DEVICE_ATTR(rs485, 0644, show_rs485, set_rs485);

Why should this be public read ?

> + /* Resetting serial mode to RS232 (0x0) */
> + mode &= ~ATMEL_US_USMODE;
> +
> + if (atmel_port->rs485.flags & SER_RS485_ENABLED) {
> + dev_dbg(port->dev, "Setting UART to RS485\n");
> + UART_PUT_TTGR(port, atmel_port->rs485.delay_rts_before_send);
> + mode |= ATMEL_US_USMODE_RS485;
> + } else {
> + dev_dbg(port->dev, "Setting UART to RS232\n");

Locking versus sysfs ?

> + UART_PUT_IDR(port, atmel_port->tx_done_mask);
> +
> + if (atmel_port->rs485.flags & SER_RS485_ENABLED)
> + atmel_start_rx(port);
> }

Ditto

> - UART_PUT_IER(port, ATMEL_US_ENDTX | ATMEL_US_TXBUFE);
> + if (atmel_port->rs485.flags & SER_RS485_ENABLED)
> + atmel_stop_rx(port);
> +

Ditto


Given the locking mess you are going to create I would suggest dropping
the sysfs stuff.

Alan


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