mpc52xx_uart and rs485
>From bf050adbc092043c1ba6e43373563bb761bb2e40 Mon Sep 17 00:00:00 2001
From: Sinisa Denic <[EMAIL PROTECTED]>
Date: Wed, 13 Aug 2008 15:57:52 +0200
Subject: [PATCH] mpc52xx_uart RS485 support added
Hi Wolfgang and others,
below is patch for mpc52xx_usrt.c which add software rs485 support to
this driver.
It has worked for me and if you think it is good enough it might be
useful for someone else.
Regards,
Sinisa Denic
System and software engineer
tel: +381(0)112016142
ABS Control Systems
bul.Zorana Djindjica 8a
Belgrade,Serbia
---
drivers/serial/mpc52xx_uart.c | 47 +
+---
1 files changed, 39 insertions(+), 8 deletions(-)
diff --git a/drivers/serial/mpc52xx_uart.c b/drivers/serial/mpc52xx_uart.c
index 7a3625f..38b2751 100644
--- a/drivers/serial/mpc52xx_uart.c
+++ b/drivers/serial/mpc52xx_uart.c
@@ -62,7 +62,7 @@
* by the bootloader or in the platform init code.
*/
-#undef DEBUG
+//#undef DEBUG
#include
#include
@@ -142,11 +142,13 @@ struct psc_ops {
int (*rx_rdy)(struct uart_port *port);
int (*tx_rdy)(struct uart_port *port);
int (*tx_empty)(struct uart_port *port);
+ int (*tx_empty_enabled)(struct uart_port *port);
void(*stop_rx)(struct uart_port *port);
void(*start_tx)(struct uart_port *port);
void(*stop_tx)(struct uart_port *port);
void(*rx_clr_irq)(struct uart_port *port);
void(*tx_clr_irq)(struct uart_port *port);
+ void(*tx_empty_clr_irq)(struct uart_port *port);
void(*write_char)(struct uart_port *port, unsigned
char c);
unsigned char (*read_char)(struct uart_port *port);
void(*cw_disable_ints)(struct uart_port *port);
@@ -169,7 +171,7 @@ static void mpc52xx_psc_fifo_init(struct uart_port
*port)
out_8(&fifo->tfcntl, 0x07);
out_be16(&fifo->tfalarm, 0x80);
- port->read_status_mask |= MPC52xx_PSC_IMR_RXRDY |
MPC52xx_PSC_IMR_TXRDY;
+ port->read_status_mask |= MPC52xx_PSC_IMR_RXRDY |
MPC52xx_PSC_IMR_TXRDY | MPC52xx_PSC_IMR_TXEMP;
out_be16(&psc->mpc52xx_psc_imr, port->read_status_mask);
}
@@ -200,6 +202,13 @@ static int mpc52xx_psc_tx_rdy(struct uart_port *port)
& MPC52xx_PSC_IMR_TXRDY;
}
+static int mpc52xx_psc_tx_empty_enabled(struct uart_port *port)
+{
+ return in_be16(&PSC(port)->mpc52xx_psc_isr)
+ & port->read_status_mask
+ & MPC52xx_PSC_IMR_TXEMP;
+}
+
static int mpc52xx_psc_tx_empty(struct uart_port *port)
{
return in_be16(&PSC(port)->mpc52xx_psc_status)
@@ -209,6 +218,7 @@ static int mpc52xx_psc_tx_empty(struct uart_port
*port)
static void mpc52xx_psc_start_tx(struct uart_port *port)
{
port->read_status_mask |= MPC52xx_PSC_IMR_TXRDY;
+ port->read_status_mask |= MPC52xx_PSC_IMR_TXEMP;
out_be16(&PSC(port)->mpc52xx_psc_imr, port->read_status_mask);
}
@@ -232,6 +242,11 @@ static void mpc52xx_psc_tx_clr_irq(struct uart_port
*port)
{
}
+static void mpc52xx_psc_tx_empty_clr_irq(struct uart_port *port)
+{
+ port->read_status_mask &= ~MPC52xx_PSC_IMR_TXEMP;
+ out_be16(&PSC(port)->mpc52xx_psc_imr, port->read_status_mask);
+}
static void mpc52xx_psc_write_char(struct uart_port *port, unsigned char
c)
{
out_8(&PSC(port)->mpc52xx_psc_buffer_8, c);
@@ -275,11 +290,13 @@ static struct psc_ops mpc52xx_psc_ops = {
.rx_rdy = mpc52xx_psc_rx_rdy,
.tx_rdy = mpc52xx_psc_tx_rdy,
.tx_empty = mpc52xx_psc_tx_empty,
+ .tx_empty_enabled = mpc52xx_psc_tx_empty_enabled,
.stop_rx = mpc52xx_psc_stop_rx,
.start_tx = mpc52xx_psc_start_tx,
.stop_tx = mpc52xx_psc_stop_tx,
.rx_clr_irq = mpc52xx_psc_rx_clr_irq,
.tx_clr_irq = mpc52xx_psc_tx_clr_irq,
+ .tx_empty_clr_irq = mpc52xx_psc_tx_empty_clr_irq,
.write_char = mpc52xx_psc_write_char,
.read_char = mpc52xx_psc_read_char,
.cw_disable_ints = mpc52xx_psc_cw_disable_ints,
@@ -583,7 +600,7 @@ mpc52xx_uart_set_termios(struct uart_port *port,
struct ktermios *new,
mr2 = 0;
-
+
if (new->c_cflag & CSTOPB)
mr2 |= MPC52xx_PSC_MODE_TWO_STOP;
else
@@ -591,7 +608,6 @@ mpc52xx_uart_set_termios(struct uart_port *port,
struct ktermios *new,
MPC52xx_PSC_MODE_ONE_STOP_5_BITS :
MPC52xx_PSC_MODE_ONE_STOP;
-
baud = uart_get_baud_rate(port, new, old, 0, port->uartclk/16);
quot = uart_get_divisor(port, baud);
ctr = quot & 0x;
@@ -735,7 +751,7 @@ mpc52xx_uart_int_rx_chars(struct uart_port *port)
struct tty_struct *tty = port->info->tty;
unsigned char ch, flag;
unsigned short status;
-
+ //printk("Int. citanje...\n");
/* While we can read, do so ! */
while (psc_ops->raw_rx_rdy(port)) {
Re: mpc52xx_uart and rs485
On Thu, Aug 14, 2008 at 11:23:49AM +0200, Sinisa Denic wrote:
> From bf050adbc092043c1ba6e43373563bb761bb2e40 Mon Sep 17 00:00:00 2001
> From: Sinisa Denic <[EMAIL PROTECTED]>
> Date: Wed, 13 Aug 2008 15:57:52 +0200
> Subject: [PATCH] mpc52xx_uart RS485 support added
>
> Hi Wolfgang and others,
> below is patch for mpc52xx_usrt.c which add software rs485 support to
> this driver.
> It has worked for me and if you think it is good enough it might be
> useful for someone else.
Thanks for the patch. I've made a number of comments below and it
appears that your mail client has damaged the patch. Can you please
respin after addressing the comments. When you repost, please include a
technical description of what you have done and why.
Thanks,
g.
> ---
> drivers/serial/mpc52xx_uart.c | 47 +
> +---
> 1 files changed, 39 insertions(+), 8 deletions(-)
>
> diff --git a/drivers/serial/mpc52xx_uart.c b/drivers/serial/mpc52xx_uart.c
> index 7a3625f..38b2751 100644
> --- a/drivers/serial/mpc52xx_uart.c
> +++ b/drivers/serial/mpc52xx_uart.c
> @@ -62,7 +62,7 @@
> * by the bootloader or in the platform init code.
> */
>
> -#undef DEBUG
> +//#undef DEBUG
Unrelated changes; please remove.
>
> #include
> #include
> @@ -142,11 +142,13 @@ struct psc_ops {
> int (*rx_rdy)(struct uart_port *port);
> int (*tx_rdy)(struct uart_port *port);
> int (*tx_empty)(struct uart_port *port);
> + int (*tx_empty_enabled)(struct uart_port *port);
> void(*stop_rx)(struct uart_port *port);
> void(*start_tx)(struct uart_port *port);
> void(*stop_tx)(struct uart_port *port);
> void(*rx_clr_irq)(struct uart_port *port);
> void(*tx_clr_irq)(struct uart_port *port);
> + void(*tx_empty_clr_irq)(struct uart_port *port);
> void(*write_char)(struct uart_port *port, unsigned
> char c);
> unsigned char (*read_char)(struct uart_port *port);
> void(*cw_disable_ints)(struct uart_port *port);
> @@ -169,7 +171,7 @@ static void mpc52xx_psc_fifo_init(struct uart_port
> *port)
> out_8(&fifo->tfcntl, 0x07);
> out_be16(&fifo->tfalarm, 0x80);
>
> - port->read_status_mask |= MPC52xx_PSC_IMR_RXRDY |
> MPC52xx_PSC_IMR_TXRDY;
> + port->read_status_mask |= MPC52xx_PSC_IMR_RXRDY |
> MPC52xx_PSC_IMR_TXRDY | MPC52xx_PSC_IMR_TXEMP;
Patch was line wrapped here by your mailer
> out_be16(&psc->mpc52xx_psc_imr, port->read_status_mask);
> }
>
> @@ -200,6 +202,13 @@ static int mpc52xx_psc_tx_rdy(struct uart_port *port)
> & MPC52xx_PSC_IMR_TXRDY;
> }
>
> +static int mpc52xx_psc_tx_empty_enabled(struct uart_port *port)
> +{
> + return in_be16(&PSC(port)->mpc52xx_psc_isr)
> + & port->read_status_mask
> + & MPC52xx_PSC_IMR_TXEMP;
> +}
> +
> static int mpc52xx_psc_tx_empty(struct uart_port *port)
> {
> return in_be16(&PSC(port)->mpc52xx_psc_status)
> @@ -209,6 +218,7 @@ static int mpc52xx_psc_tx_empty(struct uart_port
> *port)
> static void mpc52xx_psc_start_tx(struct uart_port *port)
> {
> port->read_status_mask |= MPC52xx_PSC_IMR_TXRDY;
> + port->read_status_mask |= MPC52xx_PSC_IMR_TXEMP;
You're enabling the TXEMP interrupts unconditionally, regardless of
whether or not rs485 is used. This adds performance impact to
non-rs485 users.
> out_be16(&PSC(port)->mpc52xx_psc_imr, port->read_status_mask);
> }
>
> @@ -232,6 +242,11 @@ static void mpc52xx_psc_tx_clr_irq(struct uart_port
> *port)
> {
> }
>
> +static void mpc52xx_psc_tx_empty_clr_irq(struct uart_port *port)
> +{
> + port->read_status_mask &= ~MPC52xx_PSC_IMR_TXEMP;
> + out_be16(&PSC(port)->mpc52xx_psc_imr, port->read_status_mask);
> +}
> static void mpc52xx_psc_write_char(struct uart_port *port, unsigned char
> c)
> {
> out_8(&PSC(port)->mpc52xx_psc_buffer_8, c);
> @@ -275,11 +290,13 @@ static struct psc_ops mpc52xx_psc_ops = {
> .rx_rdy = mpc52xx_psc_rx_rdy,
> .tx_rdy = mpc52xx_psc_tx_rdy,
> .tx_empty = mpc52xx_psc_tx_empty,
> + .tx_empty_enabled = mpc52xx_psc_tx_empty_enabled,
> .stop_rx = mpc52xx_psc_stop_rx,
> .start_tx = mpc52xx_psc_start_tx,
> .stop_tx = mpc52xx_psc_stop_tx,
> .rx_clr_irq = mpc52xx_psc_rx_clr_irq,
> .tx_clr_irq = mpc52xx_psc_tx_clr_irq,
> + .tx_empty_clr_irq = mpc52xx_psc_tx_empty_clr_irq,
> .write_char = mpc52xx_psc_write_char,
> .read_char = mpc52xx_psc_read_char,
> .cw_disable_ints = mpc52xx_psc_cw_disable_ints,
> @@ -583,7 +600,7 @@ mpc52xx_uart_set_termios(struct uart_port *port,
> struct ktermios *new,
>
>
> mr2 = 0;
> -
> +
Unrelated whitespace change; please omit from patch
> if (new->c_cflag & CSTOPB)
> mr2 |= MPC52xx_PSC_MODE_TWO_STOP;
> else
> @@ -591,7 +608,6 @@ mpc52xx_uart_set_
Re: mpc52xx_uart and rs485
Hello, On Wed, Sep 24, 2008 at 08:20:16AM -0600, Grant Likely wrote: > > Hi Wolfgang and others, > > below is patch for mpc52xx_usrt.c which add software rs485 support to > > this driver. > > It has worked for me and if you think it is good enough it might be > > useful for someone else. > > Thanks for the patch. I've made a number of comments below and it > appears that your mail client has damaged the patch. Can you please > respin after addressing the comments. When you repost, please include a > technical description of what you have done and why. And please add linux-serial as cc then. I recently read some criticism about software RS485 (http://article.gmane.org/gmane.linux.serial/2573). I don't know if these apply to this patch, but it would be nice to have it sorted out IMHO. All the best, Wolfram -- Dipl.-Ing. Wolfram Sang | http://www.pengutronix.de Pengutronix - Linux Solutions for Science and Industry signature.asc Description: Digital signature ___ Linuxppc-dev mailing list Linuxppc-dev@ozlabs.org https://ozlabs.org/mailman/listinfo/linuxppc-dev
