Re: [PATCH] RS485: fix inconsistencies in the meaning of somevariables

From: Jesper Nilsson
Date: Fri Nov 04 2011 - 06:37:05 EST

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In reply to: Claudio Scordino: "[PATCH] RS485: fix inconsistencies in the meaning of some variables"
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On Fri, Nov 04, 2011 at 09:19:21AM +0100, Claudio Scordino wrote:
> Hi Alan, Hi Greg,
>
> it seems that the crisv10.c and the atmel_serial.c serial
> drivers interpret the fields of the serial_rs485 structure in a different
> way.
>
> In particular, it seems that crisv10.c uses SER_RS485_RTS_AFTER_SEND and
> SER_RS485_RTS_ON_SEND for the _logic value_ of the RTS pin;
> atmel_serial.c, instead, uses these values to know if a _delay_ must be
> set before and after sending.
>
> This patch makes the usage of these variables consistent across all
> drivers and fixes the Documentation as well.
> In particular, SER_RS485_RTS_AFTER_SEND and SER_RS485_RTS_ON_SEND will
> be used to set the logic value of the RTS pin (as in the crisv10.c
> driver); the delay is understood by looking only at the value of
> delay_rts_before_send and delay_rts_after_send.

Looks good!

Acked-by: Jesper Nilsson <jesper.nilsson@xxxxxxxx>

> Claudio

/Jesper

>
> Subject: RS485: fix inconsistencies in the meaning of some variables
> From: Claudio Scordino <claudio@xxxxxxxxxxxxxxx>
>
> The crisv10.c and the atmel_serial.c serial drivers interpret the fields
> of the serial_rs485 structure in a different way.
> In particular, crisv10.c uses SER_RS485_RTS_AFTER_SEND and
> SER_RS485_RTS_ON_SEND for the voltage of the RTS pin; atmel_serial.c, instead,
> uses these values to know if a delay must be set before and after sending.
> This patch makes the usage of these variables consistent across all drivers and
> fixes the Documentation as well.
> >From now on, SER_RS485_RTS_AFTER_SEND and SER_RS485_RTS_ON_SEND will be used to
> set the voltage of the RTS pin (as in the crisv10.c driver); the delay will be
> understood by looking only at the value of delay_rts_before_send and
> delay_rts_after_send.
>
> Signed-off-by: Claudio Scordino <claudio@xxxxxxxxxxxxxxx>
> Signed-off-by: Darron Black <darron@xxxxxxxxxxx>
> ---
> Documentation/serial/serial-rs485.txt | 14 +++++++++++---
> drivers/tty/serial/atmel_serial.c | 20 +++++---------------
> drivers/tty/serial/crisv10.c | 10 ++--------
> include/linux/serial.h | 14 ++++++++------
> 4 files changed, 26 insertions(+), 32 deletions(-)
>
> diff --git a/Documentation/serial/serial-rs485.txt b/Documentation/serial/serial-rs485.txt
> index 079cb3d..d3a7388 100644
> --- a/Documentation/serial/serial-rs485.txt
> +++ b/Documentation/serial/serial-rs485.txt
> @@ -97,15 +97,23 @@
>
> struct serial_rs485 rs485conf;
>
> - /* Set RS485 mode: */
> + /* Enable RS485 mode: */
> rs485conf.flags |= SER_RS485_ENABLED;
>
> + /* Set voltage value for RTS pin equal to 1 when sending: */
> + rs485conf.flags |= SER_RS485_RTS_ON_SEND;
> + /* or, set voltage value for RTS pin equal to 0 when sending: */
> + rs485conf.flags &= ~(SER_RS485_RTS_ON_SEND);
> +
> + /* Set voltage value for RTS pin equal to 1 after sending: */
> + rs485conf.flags |= SER_RS485_RTS_AFTER_SEND;
> + /* or, set voltage value for RTS pin equal to 0 after sending: */
> + rs485conf.flags &= ~(SER_RS485_RTS_AFTER_SEND);
> +
> /* Set rts delay before send, if needed: */
> - rs485conf.flags |= SER_RS485_RTS_BEFORE_SEND;
> rs485conf.delay_rts_before_send = ...;
>
> /* Set rts delay after send, if needed: */
> - rs485conf.flags |= SER_RS485_RTS_AFTER_SEND;
> rs485conf.delay_rts_after_send = ...;
>
> /* Set this flag if you want to receive data even whilst sending data */
> diff --git a/drivers/tty/serial/atmel_serial.c b/drivers/tty/serial/atmel_serial.c
> index 4a0f86f..23aa677 100644
> --- a/drivers/tty/serial/atmel_serial.c
> +++ b/drivers/tty/serial/atmel_serial.c
> @@ -228,7 +228,7 @@ void atmel_config_rs485(struct uart_port *port, struct serial_rs485 *rs485conf)
> if (rs485conf->flags & SER_RS485_ENABLED) {
> dev_dbg(port->dev, "Setting UART to RS485\n");
> atmel_port->tx_done_mask = ATMEL_US_TXEMPTY;
> - if (rs485conf->flags & SER_RS485_RTS_AFTER_SEND)
> + if ((rs485conf->delay_rts_after_send) > 0)
> UART_PUT_TTGR(port, rs485conf->delay_rts_after_send);
> mode |= ATMEL_US_USMODE_RS485;
> } else {
> @@ -304,9 +304,9 @@ static void atmel_set_mctrl(struct uart_port *port, u_int mctrl)
>
> if (atmel_port->rs485.flags & SER_RS485_ENABLED) {
> dev_dbg(port->dev, "Setting UART to RS485\n");
> - if (atmel_port->rs485.flags & SER_RS485_RTS_AFTER_SEND)
> + if ((atmel_port->rs485.delay_rts_after_send) > 0)
> UART_PUT_TTGR(port,
> - atmel_port->rs485.delay_rts_after_send);
> + atmel_port->rs485.delay_rts_after_send);
> mode |= ATMEL_US_USMODE_RS485;
> } else {
> dev_dbg(port->dev, "Setting UART to RS232\n");
> @@ -1228,9 +1228,9 @@ static void atmel_set_termios(struct uart_port *port, struct ktermios *termios,
>
> if (atmel_port->rs485.flags & SER_RS485_ENABLED) {
> dev_dbg(port->dev, "Setting UART to RS485\n");
> - if (atmel_port->rs485.flags & SER_RS485_RTS_AFTER_SEND)
> + if ((atmel_port->rs485.delay_rts_after_send) > 0)
> UART_PUT_TTGR(port,
> - atmel_port->rs485.delay_rts_after_send);
> + atmel_port->rs485.delay_rts_after_send);
> mode |= ATMEL_US_USMODE_RS485;
> } else {
> dev_dbg(port->dev, "Setting UART to RS232\n");
> @@ -1447,16 +1447,6 @@ static void __devinit atmel_of_init_port(struct atmel_uart_port *atmel_port,
> rs485conf->delay_rts_after_send = rs485_delay[1];
> rs485conf->flags = 0;
>
> - if (rs485conf->delay_rts_before_send == 0 &&
> - rs485conf->delay_rts_after_send == 0) {
> - rs485conf->flags |= SER_RS485_RTS_ON_SEND;
> - } else {
> - if (rs485conf->delay_rts_before_send)
> - rs485conf->flags |= SER_RS485_RTS_BEFORE_SEND;
> - if (rs485conf->delay_rts_after_send)
> - rs485conf->flags |= SER_RS485_RTS_AFTER_SEND;
> - }
> -
> if (of_get_property(np, "rs485-rx-during-tx", NULL))
> rs485conf->flags |= SER_RS485_RX_DURING_TX;
>
> diff --git a/drivers/tty/serial/crisv10.c b/drivers/tty/serial/crisv10.c
> index b743504..1dfba7b 100644
> --- a/drivers/tty/serial/crisv10.c
> +++ b/drivers/tty/serial/crisv10.c
> @@ -3234,9 +3234,8 @@ rs_write(struct tty_struct *tty,
> e100_disable_rx(info);
> e100_enable_rx_irq(info);
> #endif
> - if ((info->rs485.flags & SER_RS485_RTS_BEFORE_SEND) &&
> - (info->rs485.delay_rts_before_send > 0))
> - msleep(info->rs485.delay_rts_before_send);
> + if (info->rs485.delay_rts_before_send > 0)
> + msleep(info->rs485.delay_rts_before_send);
> }
> #endif /* CONFIG_ETRAX_RS485 */
>
> @@ -3693,10 +3692,6 @@ rs_ioctl(struct tty_struct *tty,
>
> rs485data.delay_rts_before_send = rs485ctrl.delay_rts_before_send;
> rs485data.flags = 0;
> - if (rs485data.delay_rts_before_send != 0)
> - rs485data.flags |= SER_RS485_RTS_BEFORE_SEND;
> - else
> - rs485data.flags &= ~(SER_RS485_RTS_BEFORE_SEND);
>
> if (rs485ctrl.enabled)
> rs485data.flags |= SER_RS485_ENABLED;
> @@ -4531,7 +4526,6 @@ static int __init rs_init(void)
> /* Set sane defaults */
> info->rs485.flags &= ~(SER_RS485_RTS_ON_SEND);
> info->rs485.flags |= SER_RS485_RTS_AFTER_SEND;
> - info->rs485.flags &= ~(SER_RS485_RTS_BEFORE_SEND);
> info->rs485.delay_rts_before_send = 0;
> info->rs485.flags &= ~(SER_RS485_ENABLED);
> #endif
> diff --git a/include/linux/serial.h b/include/linux/serial.h
> index 97ff8e2..5a9fd4a 100644
> --- a/include/linux/serial.h
> +++ b/include/linux/serial.h
> @@ -207,13 +207,15 @@ struct serial_icounter_struct {
>
> struct serial_rs485 {
> __u32 flags; /* RS485 feature flags */
> -#define SER_RS485_ENABLED (1 << 0)
> -#define SER_RS485_RTS_ON_SEND (1 << 1)
> -#define SER_RS485_RTS_AFTER_SEND (1 << 2)
> -#define SER_RS485_RTS_BEFORE_SEND (1 << 3)
> +#define SER_RS485_ENABLED (1 << 0) /* If enabled */
> +#define SER_RS485_RTS_ON_SEND (1 << 1) /* Voltage value for
> + RTS pin when
> + sending */
> +#define SER_RS485_RTS_AFTER_SEND (1 << 2) /* Voltage value for
> + RTS pin after sent*/
> #define SER_RS485_RX_DURING_TX (1 << 4)
> - __u32 delay_rts_before_send; /* Milliseconds */
> - __u32 delay_rts_after_send; /* Milliseconds */
> + __u32 delay_rts_before_send; /* Delay before send (milliseconds) */
> + __u32 delay_rts_after_send; /* Delay after send (milliseconds) */
> __u32 padding[5]; /* Memory is cheap, new structs
> are a royal PITA .. */
> };
> --
> 1.7.1
/^JN - Jesper Nilsson
--
Jesper Nilsson -- jesper.nilsson@xxxxxxxx
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Next message: Marek Szyprowski: "RE: [PATCH 6/9] drivers: add Contiguous Memory Allocator"
Previous message: Rusty Russell: "Re: [PATCH 3 of 5] virtio: support unlocked queue kick"
In reply to: Claudio Scordino: "[PATCH] RS485: fix inconsistencies in the meaning of some variables"
Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]