2023-07-19 05:23:15

by Tony Lindgren

[permalink] [raw]
Subject: [PATCH] serial: core: Fix serial core port id to not use port->line

The serial core port id should be serial core controller specific port
instance, which is not always the port->line index.

For example, 8250 driver maps a number of legacy ports, and when a
hardware specific device driver takes over, we typically have one
driver instance for each port. Let's instead add port->port_id to
keep track serial ports mapped to each serial core controller instance.

Currently this is only a cosmetic issue for the serial core port device
names. The issue can be noticed looking at /sys/bus/serial-base/devices
for example though. Let's fix the issue to avoid port addressing issues
later on.

Fixes: 84a9582fd203 ("serial: core: Start managing serial controllers to enable runtime PM")
Signed-off-by: Tony Lindgren <[email protected]>
---
drivers/tty/serial/8250/8250_core.c | 2 ++
drivers/tty/serial/serial_base_bus.c | 2 +-
include/linux/serial_core.h | 1 +
3 files changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/tty/serial/8250/8250_core.c b/drivers/tty/serial/8250/8250_core.c
--- a/drivers/tty/serial/8250/8250_core.c
+++ b/drivers/tty/serial/8250/8250_core.c
@@ -497,6 +497,7 @@ static struct uart_8250_port *serial8250_setup_port(int index)

up = &serial8250_ports[index];
up->port.line = index;
+ up->port.port_id = index;

serial8250_init_port(up);
if (!base_ops)
@@ -1040,6 +1041,7 @@ int serial8250_register_8250_port(const struct uart_8250_port *up)
uart_remove_one_port(&serial8250_reg, &uart->port);

uart->port.ctrl_id = up->port.ctrl_id;
+ uart->port.port_id = up->port.port_id;
uart->port.iobase = up->port.iobase;
uart->port.membase = up->port.membase;
uart->port.irq = up->port.irq;
diff --git a/drivers/tty/serial/serial_base_bus.c b/drivers/tty/serial/serial_base_bus.c
--- a/drivers/tty/serial/serial_base_bus.c
+++ b/drivers/tty/serial/serial_base_bus.c
@@ -136,7 +136,7 @@ struct serial_port_device *serial_base_port_add(struct uart_port *port,
err = serial_base_device_init(port, &port_dev->dev,
&ctrl_dev->dev, &serial_port_type,
serial_base_port_release,
- port->line);
+ port->port_id);
if (err)
goto err_put_device;

diff --git a/include/linux/serial_core.h b/include/linux/serial_core.h
--- a/include/linux/serial_core.h
+++ b/include/linux/serial_core.h
@@ -460,6 +460,7 @@ struct uart_port {
int (*iso7816_config)(struct uart_port *,
struct serial_iso7816 *iso7816);
int ctrl_id; /* optional serial core controller id */
+ int port_id; /* optional serial core port id */
unsigned int irq; /* irq number */
unsigned long irqflags; /* irq flags */
unsigned int uartclk; /* base uart clock */
--
2.41.0


2023-07-19 05:32:49

by Andy Shevchenko

[permalink] [raw]
Subject: Re: [PATCH] serial: core: Fix serial core port id to not use port->line

On Wed, Jul 19, 2023 at 08:12:33AM +0300, Tony Lindgren wrote:
> The serial core port id should be serial core controller specific port
> instance, which is not always the port->line index.
>
> For example, 8250 driver maps a number of legacy ports, and when a
> hardware specific device driver takes over, we typically have one
> driver instance for each port. Let's instead add port->port_id to
> keep track serial ports mapped to each serial core controller instance.
>
> Currently this is only a cosmetic issue for the serial core port device
> names. The issue can be noticed looking at /sys/bus/serial-base/devices
> for example though. Let's fix the issue to avoid port addressing issues
> later on.

Good catch!
Reviewed-by: Andy Shevchenko <[email protected]>

> Fixes: 84a9582fd203 ("serial: core: Start managing serial controllers to enable runtime PM")
> Signed-off-by: Tony Lindgren <[email protected]>
> ---
> drivers/tty/serial/8250/8250_core.c | 2 ++
> drivers/tty/serial/serial_base_bus.c | 2 +-
> include/linux/serial_core.h | 1 +
> 3 files changed, 4 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/tty/serial/8250/8250_core.c b/drivers/tty/serial/8250/8250_core.c
> --- a/drivers/tty/serial/8250/8250_core.c
> +++ b/drivers/tty/serial/8250/8250_core.c
> @@ -497,6 +497,7 @@ static struct uart_8250_port *serial8250_setup_port(int index)
>
> up = &serial8250_ports[index];
> up->port.line = index;
> + up->port.port_id = index;
>
> serial8250_init_port(up);
> if (!base_ops)
> @@ -1040,6 +1041,7 @@ int serial8250_register_8250_port(const struct uart_8250_port *up)
> uart_remove_one_port(&serial8250_reg, &uart->port);
>
> uart->port.ctrl_id = up->port.ctrl_id;
> + uart->port.port_id = up->port.port_id;
> uart->port.iobase = up->port.iobase;
> uart->port.membase = up->port.membase;
> uart->port.irq = up->port.irq;
> diff --git a/drivers/tty/serial/serial_base_bus.c b/drivers/tty/serial/serial_base_bus.c
> --- a/drivers/tty/serial/serial_base_bus.c
> +++ b/drivers/tty/serial/serial_base_bus.c
> @@ -136,7 +136,7 @@ struct serial_port_device *serial_base_port_add(struct uart_port *port,
> err = serial_base_device_init(port, &port_dev->dev,
> &ctrl_dev->dev, &serial_port_type,
> serial_base_port_release,
> - port->line);
> + port->port_id);
> if (err)
> goto err_put_device;
>
> diff --git a/include/linux/serial_core.h b/include/linux/serial_core.h
> --- a/include/linux/serial_core.h
> +++ b/include/linux/serial_core.h
> @@ -460,6 +460,7 @@ struct uart_port {
> int (*iso7816_config)(struct uart_port *,
> struct serial_iso7816 *iso7816);
> int ctrl_id; /* optional serial core controller id */
> + int port_id; /* optional serial core port id */
> unsigned int irq; /* irq number */
> unsigned long irqflags; /* irq flags */
> unsigned int uartclk; /* base uart clock */
> --
> 2.41.0

--
With Best Regards,
Andy Shevchenko



2023-07-19 05:33:07

by Jiri Slaby

[permalink] [raw]
Subject: Re: [PATCH] serial: core: Fix serial core port id to not use port->line

On 19. 07. 23, 7:12, Tony Lindgren wrote:
> The serial core port id should be serial core controller specific port
> instance, which is not always the port->line index.
>
> For example, 8250 driver maps a number of legacy ports, and when a
> hardware specific device driver takes over, we typically have one
> driver instance for each port. Let's instead add port->port_id to
> keep track serial ports mapped to each serial core controller instance.
>
> Currently this is only a cosmetic issue for the serial core port device
> names. The issue can be noticed looking at /sys/bus/serial-base/devices
> for example though. Let's fix the issue to avoid port addressing issues
> later on.

...
> --- a/include/linux/serial_core.h
> +++ b/include/linux/serial_core.h
> @@ -460,6 +460,7 @@ struct uart_port {
> int (*iso7816_config)(struct uart_port *,
> struct serial_iso7816 *iso7816);
> int ctrl_id; /* optional serial core controller id */
> + int port_id; /* optional serial core port id */

Can the id be negative? If not, please use uint.

thanks,
--
js
suse labs


2023-07-19 06:06:13

by Jiri Slaby

[permalink] [raw]
Subject: Re: [PATCH] serial: core: Fix serial core port id to not use port->line

On 19. 07. 23, 7:34, Andy Shevchenko wrote:
> On Wed, Jul 19, 2023 at 07:26:41AM +0200, Jiri Slaby wrote:
>> On 19. 07. 23, 7:12, Tony Lindgren wrote:
>
> ...
>
>>> int ctrl_id; /* optional serial core controller id */
>>> + int port_id; /* optional serial core port id */
>>
>> Can the id be negative? If not, please use uint.
>
> Does this suggestion apply to ctrl_id as well?

Sure, but he hasn't added it in this series ;). So it should go to
someone's todo :P.

--
js
suse labs


2023-07-19 06:13:48

by Tony Lindgren

[permalink] [raw]
Subject: Re: [PATCH] serial: core: Fix serial core port id to not use port->line

* Jiri Slaby <[email protected]> [230719 05:37]:
> On 19. 07. 23, 7:34, Andy Shevchenko wrote:
> > On Wed, Jul 19, 2023 at 07:26:41AM +0200, Jiri Slaby wrote:
> > > On 19. 07. 23, 7:12, Tony Lindgren wrote:
> >
> > ...
> >
> > > > int ctrl_id; /* optional serial core controller id */
> > > > + int port_id; /* optional serial core port id */
> > >
> > > Can the id be negative? If not, please use uint.
> >
> > Does this suggestion apply to ctrl_id as well?
>
> Sure, but he hasn't added it in this series ;). So it should go to someone's
> todo :P.

Yes it can be uint, that's left over from some earlier revision where -ENODEV
was used, will fix that too.

Regards,

Tony

2023-07-19 06:33:21

by Andy Shevchenko

[permalink] [raw]
Subject: Re: [PATCH] serial: core: Fix serial core port id to not use port->line

On Wed, Jul 19, 2023 at 07:26:41AM +0200, Jiri Slaby wrote:
> On 19. 07. 23, 7:12, Tony Lindgren wrote:

...

> > int ctrl_id; /* optional serial core controller id */
> > + int port_id; /* optional serial core port id */
>
> Can the id be negative? If not, please use uint.

Does this suggestion apply to ctrl_id as well?

--
With Best Regards,
Andy Shevchenko