Re: [PATCH] max3100 driver

Alan Cox
2008-09-20T14:12:30Z

> +#define MAX3100_MAJOR 204
> +#define MAX3100_MINOR 128
> +/* 4 MAX3100s should be enough for everyone */
> +#define MAX_MAX3100 4

These need to be officially allocated if you need constant numbers

> +static int max3100_sr(struct max3100_port_s *s, u16 tx, u16 *rx)
> +{
> + struct spi_message message;
> + struct spi_transfer tran;
> + u16 etx, erx;
> + int status;
> +
> + etx = htons(tx);

Use cpu_to_le/be or le/be_to_cpu functions, these make the intended
endianness clear.

> + *rx = ntohs(erx);

Ditto

> + if (rxchars > 0)
> + tty_flip_buffer_push(s->port.info->port.tty);
> + if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)

If there has been a hangup the port.tty will be NULL...

> +static void
> +max3100_set_termios(struct uart_port *port, struct ktermios *termios,
> + struct ktermios *old)
> +{
> + struct max3100_port_s *s = container_of(port,
> + struct max3100_port_s,

> + if (!old || (termios->c_cflag != old->c_cflag)) {

This optimisation is wrong and not worth doing anyway

> + i = cflag & CBAUD;
> + switch (i) {

Use tty_get_baud_rate() to get the actual baud rate requested which is an
arbitary value.

> + default:
> + param_new = 1;
> + dev_warn(&s->spi->dev, "invalid baudrate\n");

Shouldn't warn on these, just be sure to use tty_encode_baud_rate to pass
back the actual rate the user ends up with.

> + if (termios->c_iflag & IGNPAR)
> + s->port.ignore_status_mask |=
> + MAX3100_STATUS_PE | MAX3100_STATUS_FE |
> + MAX3100_STATUS_OE;

Bits you don't support should also be cleared in the tty->termios struct
(eg markspace you don't seem to do)

> + max3100s[i] = kzalloc(sizeof(struct max3100_port_s), GFP_KERNEL);
> + if (!max3100s[i]) {
> + dev_warn(&spi->dev,
> + "kmalloc for max3100 structure %d failed!\n", i);

Does this not then need to unregister the driver ?

Looks basically sound to me - just some minor cleanups needed.

Alan