Re: [PATCH v2 1/2] tty: serial: msm: Add mask value for UART_DM registers

[Stephen Boyd <sboyd@codeaurora.org>]

On 04/08/15 06:28, Pramod Gurav wrote:
> diff --git a/drivers/tty/serial/msm_serial.c b/drivers/tty/serial/msm_serial.c
> index b73889c..4c1e9ea 100644
> --- a/drivers/tty/serial/msm_serial.c
> +++ b/drivers/tty/serial/msm_serial.c
> @@ -432,8 +432,13 @@ static int msm_set_baud_rate(struct uart_port *port, unsigned int baud)
>  	/* RX stale watermark */
>  	rxstale = entry->rxstale;
>  	watermark = UART_IPR_STALE_LSB & rxstale;
> -	watermark |= UART_IPR_RXSTALE_LAST;
> -	watermark |= UART_IPR_STALE_TIMEOUT_MSB & (rxstale << 2);
> +	if (msm_port->is_uartdm)
> +		watermark |= UART_DM_IPR_STALE_TIMEOUT_MSB & (rxstale << 2);
> +	else {
> +		watermark |= UART_IPR_RXSTALE_LAST;
> +		watermark |= UART_IPR_STALE_TIMEOUT_MSB & (rxstale << 2);
> +	}
> +
>  	msm_write(port, watermark, UART_IPR);
>  

This could be written like so:

if (msm_port->is_uartdm) {
	mask = UART_DM_IPR_STALE_TIMEOUT_MSB;
} else {
	watermark |= UART_IPR_RXSTALE_LAST;
	mask = UART_IPR_STALE_TIMEOUT_MSB;
}

watermark |= mask & (rxstale << 2);

so that we don't duplicate the rfr_level << 2 part.

>  	/* set RX watermark */
> @@ -496,9 +501,15 @@ static int msm_startup(struct uart_port *port)
>  
>  	/* set automatic RFR level */
>  	data = msm_read(port, UART_MR1);
> -	data &= ~UART_MR1_AUTO_RFR_LEVEL1;
> +	if (msm_port->is_uartdm) {
> +		data &= ~UART_DM_MR1_AUTO_RFR_LEVEL1;
> +		data |= UART_DM_MR1_AUTO_RFR_LEVEL1 & (rfr_level << 2);
> +	} else {
> +		data &= ~UART_MR1_AUTO_RFR_LEVEL1;
> +		data |= UART_MR1_AUTO_RFR_LEVEL1 & (rfr_level << 2);
> +	}
> +
>  	data &= ~UART_MR1_AUTO_RFR_LEVEL0;
> -	data |= UART_MR1_AUTO_RFR_LEVEL1 & (rfr_level << 2);
>  	data |= UART_MR1_AUTO_RFR_LEVEL0 & rfr_level;
>  	msm_write(port, data, UART_MR1);
>  	return 0;

This could be written like so:

if (msm_port->is_uartdm)
	mask = UART_DM_MR1_AUTO_RFR_LEVEL1;
else
	mask = UART_MR1_AUTO_RFR_LEVE1;

data &= ~mask;
data &= ~UART_MR1_AUTO_RFR_LEVEL0;
data |= mask & (rfr_level << 2);
data |= UART_MR1_AUTO_RFR_LEVEL0 & rfr_level;

so that we don't duplicate the rfr_level << 2 part.

-- 
Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum,
a Linux Foundation Collaborative Project