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[v6,0/3] serial: 8250_pnp: Support configurable reg shift property

Message ID cover.1712646750.git.albanhuang@tencent.com
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Series serial: 8250_pnp: Support configurable reg shift property | expand

Message

Guanbing Huang April 9, 2024, 7:43 a.m. UTC
From: Guanbing Huang <albanhuang@tencent.com>

The 16550a serial port based on the ACPI table requires obtaining the
reg-shift attribute. In the ACPI scenario, If the reg-shift property
is not configured like in DTS, the 16550a serial driver cannot read or
write controller registers properly during initialization.

To address the issue of configuring the reg-shift property, the 
__uart_read_properties() universal interface is called to implement it.
Adaptation of PNP devices is done in the __uart_read_properties() function.

Guanbing Huang (3):
  PNP: Add dev_is_pnp() macro
  serial: port: Add support of PNP IRQ to __uart_read_properties()
  serial: 8250_pnp: Support configurable reg shift property

 drivers/tty/serial/8250/8250_pnp.c | 40 +++++++++++++++++++-----------
 drivers/tty/serial/serial_port.c   |  7 +++++-
 include/linux/pnp.h                |  2 ++
 3 files changed, 33 insertions(+), 16 deletions(-)

Comments

Guanbing Huang April 10, 2024, 2:49 a.m. UTC | #1
在 2024/4/9 20:53, Andy Shevchenko 写道:
> On Tue, Apr 09, 2024 at 03:43:20PM +0800, Guanbing Huang wrote:
>> From: Guanbing Huang <albanhuang@tencent.com>
>>
>> The 16550a serial port based on the ACPI table requires obtaining the
>> reg-shift attribute. In the ACPI scenario, If the reg-shift property
>> is not configured like in DTS, the 16550a serial driver cannot read or
>> write controller registers properly during initialization.
>>
>> To address the issue of configuring the reg-shift property, the
>> __uart_read_properties() universal interface is called to implement it.
>> Adaptation of PNP devices is done in the __uart_read_properties() function.
> You either forgot or deliberately not added my tag. Can you elaborate?

I'm very sorry, this is my first time submitting a kernel patch. My 
understanding

of the submission specification is not comprehensive and profound enough,

and I didn't intentionally not add tags. I hope you can forgive my 
operational mistake.

Should I just add a "Reviewed-by tag", or do I need any other tags? Thanks.


With Best Regards.

>
Andy Shevchenko April 10, 2024, 1:40 p.m. UTC | #2
On Wed, Apr 10, 2024 at 10:49:29AM +0800, albanhuang wrote:
> 在 2024/4/9 20:53, Andy Shevchenko 写道:
> > On Tue, Apr 09, 2024 at 03:43:20PM +0800, Guanbing Huang wrote:
> > > From: Guanbing Huang <albanhuang@tencent.com>
> > > 
> > > The 16550a serial port based on the ACPI table requires obtaining the
> > > reg-shift attribute. In the ACPI scenario, If the reg-shift property
> > > is not configured like in DTS, the 16550a serial driver cannot read or
> > > write controller registers properly during initialization.
> > > 
> > > To address the issue of configuring the reg-shift property, the
> > > __uart_read_properties() universal interface is called to implement it.
> > > Adaptation of PNP devices is done in the __uart_read_properties() function.
> > You either forgot or deliberately not added my tag. Can you elaborate?
> 
> I'm very sorry, this is my first time submitting a kernel patch. My
> understanding
> 
> of the submission specification is not comprehensive and profound enough,
> 
> and I didn't intentionally not add tags. I hope you can forgive my
> operational mistake.
> 
> Should I just add a "Reviewed-by tag", or do I need any other tags? Thanks.

Understood. So if you are is one who is sending a new version, you should take
care about any given tags (such as Reviewed-by) and carry them, in case the
code is not drastically changed. I.o.w. if you don't, you have to explain why.

Anyways, it seems the patch still has a flaw as per LKP, so fix that by
providing probably two macros in the pnp.h header for both cases
(CONFIG_PNP=y/n), and I will review it again.

	#ifdef CONFIG_PNP
	...
	#define dev_is_pnp(...) ...
	...
	#else
	...
	#define dev_is_pnp(...)		false
	...
	#endif