[PATCH v4 0/3] Serial core controller port device name fixes

[PATCH v4 0/3] Serial core controller port device name fixes

[Tony Lindgren]

A few issues have been found with device naming for the serial core
controller port device. These issues currently mostly affect the output
for /sys/bus/serial-base/devices, but need to be also fixed to avoid
port addressing issues later on.

Changes since v3:
- Drop unnecessary else on the return path in serial_base_device_init()
  as noted by Andy

- Add Andy's Reviewed-by

- Update first patch description for port_id instead of port port_id
  for the first patch

Changes since v2:
- Fix my email script as it had started to drop linux-serial as noted by
  Greg

- Explain why we're changing ctrl_id as requested by Greg

Changes since v1:
- Port id cannot be negative as noted by Jiri

- Controller id cannot be negative as noted by Andy

- Port name is missing the controller instance as noted by Andy

Tony Lindgren (3):
  serial: core: Controller id cannot be negative
  serial: core: Fix serial core port id to not use port->line
  serial: core: Fix serial core controller port name to show controller
    id

 drivers/tty/serial/8250/8250_core.c  |  2 ++
 drivers/tty/serial/serial_base_bus.c | 34 ++++++++++++++++++----------
 include/linux/serial_core.h          |  3 ++-
 3 files changed, 26 insertions(+), 13 deletions(-)

-- 
2.41.0

[PATCH v4 1/3] serial: core: Controller id cannot be negative

[Tony Lindgren]

The controller id cannot be negative. Let's fix the ctrl_id in preparation
for adding port_id to fix the device name.

Fixes: 84a9582fd203 ("serial: core: Start managing serial controllers to enable runtime PM")
Reported-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
---
 include/linux/serial_core.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

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
@@ -459,7 +459,7 @@ struct uart_port {
 						struct serial_rs485 *rs485);
 	int			(*iso7816_config)(struct uart_port *,
 						  struct serial_iso7816 *iso7816);
-	int			ctrl_id;		/* optional serial core controller id */
+	unsigned int		ctrl_id;		/* optional serial core controller id */
 	unsigned int		irq;			/* irq number */
 	unsigned long		irqflags;		/* irq flags  */
 	unsigned int		uartclk;		/* base uart clock */
-- 
2.41.0

[PATCH v4 2/3] serial: core: Fix serial core port id to not use port->line

[Tony Lindgren]

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")
Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
---
 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);
 	unsigned int		ctrl_id;		/* optional serial core controller id */
+	unsigned 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

[PATCH v4 3/3] serial: core: Fix serial core controller port name to show controller id

[Tony Lindgren]

We are missing the serial core controller id for the serial core port
name. Let's fix the issue for sane /sys/bus/serial-core/devices, and to
avoid issues addressing serial ports later on.

Fixes: 84a9582fd203 ("serial: core: Start managing serial controllers to enable runtime PM")
Reported-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
---
 drivers/tty/serial/serial_base_bus.c | 34 ++++++++++++++++++----------
 1 file changed, 22 insertions(+), 12 deletions(-)

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
@@ -19,6 +19,14 @@
 
 static bool serial_base_initialized;
 
+static const struct device_type serial_ctrl_type = {
+	.name = "ctrl",
+};
+
+static const struct device_type serial_port_type = {
+	.name = "port",
+};
+
 static int serial_base_match(struct device *dev, struct device_driver *drv)
 {
 	int len = strlen(drv->name);
@@ -48,7 +56,8 @@ static int serial_base_device_init(struct uart_port *port,
 				   struct device *parent_dev,
 				   const struct device_type *type,
 				   void (*release)(struct device *dev),
-				   int id)
+				   unsigned int ctrl_id,
+				   unsigned int port_id)
 {
 	device_initialize(dev);
 	dev->type = type;
@@ -61,12 +70,17 @@ static int serial_base_device_init(struct uart_port *port,
 		return -EPROBE_DEFER;
 	}
 
-	return dev_set_name(dev, "%s.%s.%d", type->name, dev_name(port->dev), id);
-}
+	if (type == &serial_ctrl_type)
+		return dev_set_name(dev, "%s.%s.%d", type->name,
+				    dev_name(port->dev), ctrl_id);
 
-static const struct device_type serial_ctrl_type = {
-	.name = "ctrl",
-};
+	if (type == &serial_port_type)
+		return dev_set_name(dev, "%s.%s.%d.%d", type->name,
+				    dev_name(port->dev), ctrl_id,
+				    port_id);
+
+	return -EINVAL;
+}
 
 static void serial_base_ctrl_release(struct device *dev)
 {
@@ -96,7 +110,7 @@ struct serial_ctrl_device *serial_base_ctrl_add(struct uart_port *port,
 	err = serial_base_device_init(port, &ctrl_dev->dev,
 				      parent, &serial_ctrl_type,
 				      serial_base_ctrl_release,
-				      port->ctrl_id);
+				      port->ctrl_id, 0);
 	if (err)
 		goto err_put_device;
 
@@ -112,10 +126,6 @@ struct serial_ctrl_device *serial_base_ctrl_add(struct uart_port *port,
 	return ERR_PTR(err);
 }
 
-static const struct device_type serial_port_type = {
-	.name = "port",
-};
-
 static void serial_base_port_release(struct device *dev)
 {
 	struct serial_port_device *port_dev = to_serial_base_port_device(dev);
@@ -136,7 +146,7 @@ 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->port_id);
+				      port->ctrl_id, port->port_id);
 	if (err)
 		goto err_put_device;
 
-- 
2.41.0

Re: [PATCH v4 1/3] serial: core: Controller id cannot be negative

[Andy Shevchenko]

On Mon, Jul 24, 2023 at 08:07:03AM +0300, Tony Lindgren wrote:
> The controller id cannot be negative. Let's fix the ctrl_id in preparation
> for adding port_id to fix the device name.
> 
> Fixes: 84a9582fd203 ("serial: core: Start managing serial controllers to enable runtime PM")
> Reported-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>

> Andy Shevchenko <andriy.shevchenko@linux.intel.com>

???
Missing Reviewed-by: I suppose?

-- 
With Best Regards,
Andy Shevchenko

Re: [PATCH v4 1/3] serial: core: Controller id cannot be negative

[Andy Shevchenko]

On Mon, Jul 24, 2023 at 11:52:39AM +0300, Andy Shevchenko wrote:
> On Mon, Jul 24, 2023 at 08:07:03AM +0300, Tony Lindgren wrote:
> > The controller id cannot be negative. Let's fix the ctrl_id in preparation
> > for adding port_id to fix the device name.
> > 
> > Fixes: 84a9582fd203 ("serial: core: Start managing serial controllers to enable runtime PM")
> > Reported-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
> 
> > Andy Shevchenko <andriy.shevchenko@linux.intel.com>
> 
> ???
> Missing Reviewed-by: I suppose?

Seems like it wen in all patches... :-(

-- 
With Best Regards,
Andy Shevchenko

Re: [PATCH v4 3/3] serial: core: Fix serial core controller port name to show controller id

[Andy Shevchenko]

On Mon, Jul 24, 2023 at 08:07:05AM +0300, Tony Lindgren wrote:
> We are missing the serial core controller id for the serial core port
> name. Let's fix the issue for sane /sys/bus/serial-core/devices, and to
> avoid issues addressing serial ports later on.

...

> -	return dev_set_name(dev, "%s.%s.%d", type->name, dev_name(port->dev), id);
> -}
> +	if (type == &serial_ctrl_type)

	...

> +}

While at it, have you tried to use --patience when forming patches? Does it
make any (better) difference?

-- 
With Best Regards,
Andy Shevchenko

Re: [PATCH v4 3/3] serial: core: Fix serial core controller port name to show controller id

[Jiri Slaby]

On 24. 07. 23, 10:55, Andy Shevchenko wrote:
> On Mon, Jul 24, 2023 at 08:07:05AM +0300, Tony Lindgren wrote:
>> We are missing the serial core controller id for the serial core port
>> name. Let's fix the issue for sane /sys/bus/serial-core/devices, and to
>> avoid issues addressing serial ports later on.
> 
> ...
> 
>> -	return dev_set_name(dev, "%s.%s.%d", type->name, dev_name(port->dev), id);
>> -}
>> +	if (type == &serial_ctrl_type)
> 
> 	...
> 
>> +}
> 
> While at it, have you tried to use --patience when forming patches? Does it
> make any (better) difference?

Or moving "struct device_type"s to one place in a separate patch might 
do the desired trick too ;).

-- 
js
suse labs

Re: [PATCH v4 3/3] serial: core: Fix serial core controller port name to show controller id

[Tony Lindgren]

* Andy Shevchenko <andriy.shevchenko@linux.intel.com> [230724 08:56]:
> On Mon, Jul 24, 2023 at 08:07:05AM +0300, Tony Lindgren wrote:
> > We are missing the serial core controller id for the serial core port
> > name. Let's fix the issue for sane /sys/bus/serial-core/devices, and to
> > avoid issues addressing serial ports later on.
> 
> ...
> 
> > -	return dev_set_name(dev, "%s.%s.%d", type->name, dev_name(port->dev), id);
> > -}
> > +	if (type == &serial_ctrl_type)
> 
> 	...
> 
> > +}
> 
> While at it, have you tried to use --patience when forming patches? Does it
> make any (better) difference?

I'll check if it makes it more readable. Seems I need to also enable the
--patience option for myself for sending patches to avoid messing up things
like Reviewed-by tags :)

Tony