Re: [PATCH 3/5] serial: fsl_lpuart: Remove custom frame size calculation

From: Andy Shevchenko
Date: Fri Aug 26 2022 - 11:57:11 EST


On Thu, Aug 25, 2022 at 11:59 AM Ilpo Järvinen
<ilpo.jarvinen@xxxxxxxxxxxxxxx> wrote:
>
> The number of bits can be calculated using tty_get_frame_size(), no
> need for the driver to do it on its own.

...

> struct dma_slave_config dma_rx_sconfig = {};
> struct circ_buf *ring = &sport->rx_ring;
> int ret, nent;
> - int bits, baud;
> + int baud;
> struct tty_port *port = &sport->port.state->port;
> struct tty_struct *tty = port->tty;
> struct ktermios *termios = &tty->termios;
> struct dma_chan *chan = sport->dma_rx_chan;
>
> baud = tty_get_baud_rate(tty);

You can move baud and join with the assignment, right?
At the same time provide a temporary variable for bits here with the assignment.

> - bits = (termios->c_cflag & CSIZE) == CS7 ? 9 : 10;
> - if (termios->c_cflag & PARENB)
> - bits++;
> -
> /*
> * Calculate length of one DMA buffer size to keep latency below
> * 10ms at any baud rate.
> */
> - sport->rx_dma_rng_buf_len = (DMA_RX_TIMEOUT * baud / bits / 1000) * 2;

This will be left untouched.

> + sport->rx_dma_rng_buf_len = (DMA_RX_TIMEOUT * baud / tty_get_frame_size(termios->c_cflag) /
> + 1000) * 2;

And no strange indentation.

--
With Best Regards,
Andy Shevchenko