* [PATCH 2/5] altera_uart: Add support for polling mode (IRQ-less)
@ 2010-09-28 13:35 Anton Vorontsov
2010-09-28 15:45 ` Tobias Klauser
0 siblings, 1 reply; 3+ messages in thread
From: Anton Vorontsov @ 2010-09-28 13:35 UTC (permalink / raw)
To: Greg Kroah-Hartman
Cc: Alan Cox, Andrew Morton, Tobias Klauser, linux-serial,
linux-kernel
Some Altera UART implementations doesn't route the IRQ line, so we have
to work in polling mode.
Signed-off-by: Anton Vorontsov <cbouatmailru@gmail.com>
---
drivers/serial/altera_uart.c | 38 +++++++++++++++++++++++++++++---------
1 files changed, 29 insertions(+), 9 deletions(-)
diff --git a/drivers/serial/altera_uart.c b/drivers/serial/altera_uart.c
index f8d8a00..2603f59 100644
--- a/drivers/serial/altera_uart.c
+++ b/drivers/serial/altera_uart.c
@@ -15,6 +15,7 @@
#include <linux/kernel.h>
#include <linux/init.h>
+#include <linux/timer.h>
#include <linux/interrupt.h>
#include <linux/module.h>
#include <linux/console.h>
@@ -76,6 +77,7 @@
*/
struct altera_uart {
struct uart_port port;
+ struct timer_list tmr;
unsigned int sigs; /* Local copy of line sigs */
unsigned short imr; /* Local IMR mirror */
};
@@ -168,6 +170,7 @@ static void altera_uart_set_termios(struct uart_port *port,
tty_termios_encode_baud_rate(termios, baud, baud);
spin_lock_irqsave(&port->lock, flags);
+ uart_update_timeout(port, termios->c_cflag, baud);
writel(baudclk, port->membase + ALTERA_UART_DIVISOR_REG);
spin_unlock_irqrestore(&port->lock, flags);
}
@@ -268,6 +271,15 @@ static irqreturn_t altera_uart_interrupt(int irq, void *data)
return IRQ_RETVAL(isr);
}
+static void altera_uart_timer(unsigned long data)
+{
+ struct uart_port *port = (void *)data;
+ struct altera_uart *pp = container_of(port, struct altera_uart, port);
+
+ altera_uart_interrupt(0, port);
+ mod_timer(&pp->tmr, jiffies + uart_poll_timeout(port));
+}
+
static void altera_uart_config_port(struct uart_port *port, int flags)
{
port->type = PORT_ALTERA_UART;
@@ -284,14 +296,6 @@ static int altera_uart_startup(struct uart_port *port)
unsigned long flags;
int ret;
- ret = request_irq(port->irq, altera_uart_interrupt, IRQF_DISABLED,
- DRV_NAME, port);
- if (ret) {
- pr_err(DRV_NAME ": unable to attach Altera UART %d "
- "interrupt vector=%d\n", port->line, port->irq);
- return ret;
- }
-
spin_lock_irqsave(&port->lock, flags);
/* Enable RX interrupts now */
@@ -300,6 +304,19 @@ static int altera_uart_startup(struct uart_port *port)
spin_unlock_irqrestore(&port->lock, flags);
+ if (port->irq) {
+ ret = request_irq(port->irq, altera_uart_interrupt,
+ IRQF_DISABLED, DRV_NAME, port);
+ if (ret) {
+ pr_err(DRV_NAME ": unable to attach Altera UART %d "
+ "interrupt vector=%d\n", port->line, port->irq);
+ return ret;
+ }
+ } else {
+ setup_timer(&pp->tmr, altera_uart_timer, (unsigned long)port);
+ mod_timer(&pp->tmr, jiffies + uart_poll_timeout(port));
+ }
+
return 0;
}
@@ -316,7 +333,10 @@ static void altera_uart_shutdown(struct uart_port *port)
spin_unlock_irqrestore(&port->lock, flags);
- free_irq(port->irq, port);
+ if (port->irq)
+ free_irq(port->irq, port);
+ else
+ del_timer_sync(&pp->tmr);
}
static const char *altera_uart_type(struct uart_port *port)
--
1.7.0.5
^ permalink raw reply related [flat|nested] 3+ messages in thread* Re: [PATCH 2/5] altera_uart: Add support for polling mode (IRQ-less)
2010-09-28 13:35 [PATCH 2/5] altera_uart: Add support for polling mode (IRQ-less) Anton Vorontsov
@ 2010-09-28 15:45 ` Tobias Klauser
2010-10-01 13:24 ` Anton Vorontsov
0 siblings, 1 reply; 3+ messages in thread
From: Tobias Klauser @ 2010-09-28 15:45 UTC (permalink / raw)
To: Anton Vorontsov
Cc: Greg Kroah-Hartman, Alan Cox, Andrew Morton, linux-serial,
linux-kernel
On 2010-09-28 at 15:35:26 +0200, Anton Vorontsov <cbouatmailru@gmail.com> wrote:
> Some Altera UART implementations doesn't route the IRQ line, so we have
> to work in polling mode.
>
> Signed-off-by: Anton Vorontsov <cbouatmailru@gmail.com>
> ---
> drivers/serial/altera_uart.c | 38 +++++++++++++++++++++++++++++---------
> 1 files changed, 29 insertions(+), 9 deletions(-)
>
> diff --git a/drivers/serial/altera_uart.c b/drivers/serial/altera_uart.c
> index f8d8a00..2603f59 100644
> --- a/drivers/serial/altera_uart.c
> +++ b/drivers/serial/altera_uart.c
> @@ -15,6 +15,7 @@
>
> #include <linux/kernel.h>
> #include <linux/init.h>
> +#include <linux/timer.h>
> #include <linux/interrupt.h>
> #include <linux/module.h>
> #include <linux/console.h>
> @@ -76,6 +77,7 @@
> */
> struct altera_uart {
> struct uart_port port;
> + struct timer_list tmr;
> unsigned int sigs; /* Local copy of line sigs */
> unsigned short imr; /* Local IMR mirror */
> };
> @@ -168,6 +170,7 @@ static void altera_uart_set_termios(struct uart_port *port,
> tty_termios_encode_baud_rate(termios, baud, baud);
>
> spin_lock_irqsave(&port->lock, flags);
> + uart_update_timeout(port, termios->c_cflag, baud);
> writel(baudclk, port->membase + ALTERA_UART_DIVISOR_REG);
> spin_unlock_irqrestore(&port->lock, flags);
> }
> @@ -268,6 +271,15 @@ static irqreturn_t altera_uart_interrupt(int irq, void *data)
> return IRQ_RETVAL(isr);
> }
>
> +static void altera_uart_timer(unsigned long data)
> +{
> + struct uart_port *port = (void *)data;
> + struct altera_uart *pp = container_of(port, struct altera_uart, port);
> +
> + altera_uart_interrupt(0, port);
> + mod_timer(&pp->tmr, jiffies + uart_poll_timeout(port));
> +}
> +
> static void altera_uart_config_port(struct uart_port *port, int flags)
> {
> port->type = PORT_ALTERA_UART;
> @@ -284,14 +296,6 @@ static int altera_uart_startup(struct uart_port *port)
> unsigned long flags;
> int ret;
>
> - ret = request_irq(port->irq, altera_uart_interrupt, IRQF_DISABLED,
> - DRV_NAME, port);
> - if (ret) {
> - pr_err(DRV_NAME ": unable to attach Altera UART %d "
> - "interrupt vector=%d\n", port->line, port->irq);
> - return ret;
> - }
> -
> spin_lock_irqsave(&port->lock, flags);
>
> /* Enable RX interrupts now */
> @@ -300,6 +304,19 @@ static int altera_uart_startup(struct uart_port *port)
>
> spin_unlock_irqrestore(&port->lock, flags);
Shouldn't we only enable the RX interrupt if we actually use interrupts?
Also I would retain the order here (first register the interrupt handler
and then enable the interrupts).
Cheers,
Tobias
^ permalink raw reply [flat|nested] 3+ messages in thread* Re: [PATCH 2/5] altera_uart: Add support for polling mode (IRQ-less)
2010-09-28 15:45 ` Tobias Klauser
@ 2010-10-01 13:24 ` Anton Vorontsov
0 siblings, 0 replies; 3+ messages in thread
From: Anton Vorontsov @ 2010-10-01 13:24 UTC (permalink / raw)
To: Tobias Klauser
Cc: Greg Kroah-Hartman, Alan Cox, Andrew Morton, linux-serial,
linux-kernel
On Tue, Sep 28, 2010 at 05:45:39PM +0200, Tobias Klauser wrote:
[...]
> > - ret = request_irq(port->irq, altera_uart_interrupt, IRQF_DISABLED,
> > - DRV_NAME, port);
> > - if (ret) {
> > - pr_err(DRV_NAME ": unable to attach Altera UART %d "
> > - "interrupt vector=%d\n", port->line, port->irq);
> > - return ret;
> > - }
> > -
> > spin_lock_irqsave(&port->lock, flags);
> >
> > /* Enable RX interrupts now */
> > @@ -300,6 +304,19 @@ static int altera_uart_startup(struct uart_port *port)
> >
> > spin_unlock_irqrestore(&port->lock, flags);
>
> Shouldn't we only enable the RX interrupt if we actually use interrupts?
Why would that matter if we don't use the interrupts? ;-)
But I made the change anyway.
> Also I would retain the order here (first register the interrupt handler
> and then enable the interrupts).
OK, fixed. Thanks!
--
Anton Vorontsov
email: cbouatmailru@gmail.com
irc://irc.freenode.net/bd2
^ permalink raw reply [flat|nested] 3+ messages in thread
end of thread, other threads:[~2010-10-01 13:24 UTC | newest]
Thread overview: 3+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2010-09-28 13:35 [PATCH 2/5] altera_uart: Add support for polling mode (IRQ-less) Anton Vorontsov
2010-09-28 15:45 ` Tobias Klauser
2010-10-01 13:24 ` Anton Vorontsov
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox