Re: [PATCH 1/3] media: cx231xx: Convert enum into a define

Hans Verkuil
2025-02-20T13:55:48Z

On 12/3/24 09:31, Mauro Carvalho Chehab wrote:
> Em Mon, 02 Dec 2024 15:47:15 +0000
> Ricardo Ribalda <ribalda@chromium.org> escreveu:
>
>> The code is running arithmentics with the enum, which when not done with
>> care makes the compiler a bit nervous.
>>
>> Because those enums are only used as defines (no argument or variable
>> from that enumeration type), convert it into a define and move on.
>>
>> It is required to build with llvm 9 without these warnings:
>> drivers/media/usb/cx231xx/cx231xx-pcb-cfg.c:673:17: warning: bitwise operation between different enumeration types ('enum TS_PORT' and 'enum POWE_TYPE') [-Wenum-enum-conversion]
>> drivers/media/usb/cx231xx/cx231xx-pcb-cfg.c:680:21: warning: bitwise operation between different enumeration types ('enum AVDEC_STATUS' and 'enum POWE_TYPE') [-Wenum-enum-conversion]
>> drivers/media/usb/cx231xx/cx231xx-pcb-cfg.c:687:21: warning: bitwise operation between different enumeration types ('enum AVDEC_STATUS' and 'enum POWE_TYPE') [-Wenum-enum-conversion]
>> drivers/media/usb/cx231xx/cx231xx-pcb-cfg.c:702:17: warning: bitwise operation between different enumeration types ('enum TS_PORT' and 'enum POWE_TYPE') [-Wenum-enum-conversion]
>> drivers/media/usb/cx231xx/cx231xx-pcb-cfg.c:709:21: warning: bitwise operation between different enumeration types ('enum TS_PORT' and 'enum POWE_TYPE') [-Wenum-enum-conversion]
>> drivers/media/usb/cx231xx/cx231xx-pcb-cfg.c:718:21: warning: bitwise operation between different enumeration types ('enum AVDEC_STATUS' and 'enum POWE_TYPE') [-Wenum-enum-conversion]
>> drivers/media/usb/cx231xx/cx231xx-pcb-cfg.c:727:21: warning: bitwise operation between different enumeration types ('enum AVDEC_STATUS' and 'enum TS_PORT') [-Wenum-enum-conversion]
>> drivers/media/usb/cx231xx/cx231xx-pcb-cfg.c:737:21: warning: bitwise operation between different enumeration types ('enum AVDEC_STATUS' and 'enum TS_PORT') [-Wenum-enum-conversion]
>> drivers/media/usb/cx231xx/cx231xx-pcb-cfg.c:749:21: warning: bitwise operation between different enumeration types ('enum AVDEC_STATUS' and 'enum TS_PORT') [-Wenum-enum-conversion]
>>
>> Signed-off-by: Ricardo Ribalda <ribalda@chromium.org>
>> ---
>> drivers/media/usb/cx231xx/cx231xx-pcb-cfg.h | 18 +++++++-----------
>> 1 file changed, 7 insertions(+), 11 deletions(-)
>>
>> diff --git a/drivers/media/usb/cx231xx/cx231xx-pcb-cfg.h b/drivers/media/usb/cx231xx/cx231xx-pcb-cfg.h
>> index 5bc44f194d0a..62ffa16bb82c 100644
>> --- a/drivers/media/usb/cx231xx/cx231xx-pcb-cfg.h
>> +++ b/drivers/media/usb/cx231xx/cx231xx-pcb-cfg.h
>> @@ -57,19 +57,17 @@ enum USB_SPEED{
>> };
>>
>> #define TS_MASK 0x6
>> -enum TS_PORT{
>> - NO_TS_PORT = 0x0, /* 2'b00: Neither port used. PCB not a Hybrid,
>> +#define NO_TS_PORT 0x0 /* 2'b00: Neither port used. PCB not a Hybrid,
>> only offers Analog TV or Video */
>> - TS1_PORT = 0x4, /* 2'b10: TS1 Input (Hybrid mode :
>> +#define TS1_PORT 0x4 /* 2'b10: TS1 Input (Hybrid mode :
>> Digital or External Analog/Compressed source) */
>> - TS1_TS2_PORT = 0x6, /* 2'b11: TS1 & TS2 Inputs
>> +#define TS1_TS2_PORT 0x6 /* 2'b11: TS1 & TS2 Inputs
>> (Dual inputs from Digital and/or
>> External Analog/Compressed sources) */
>> - TS1_EXT_CLOCK = 0x6, /* 2'b11: TS1 & TS2 as selector
>> +#define TS1_EXT_CLOCK 0x6 /* 2'b11: TS1 & TS2 as selector
>> to external clock */
>> - TS1VIP_TS2_PORT = 0x2 /* 2'b01: TS1 used as 656/VIP Output,
>> +#define TS1VIP_TS2_PORT 0x2 /* 2'b01: TS1 used as 656/VIP Output,
>> TS2 Input (from Compressor) */
>> -};
>>
>> #define EAVP_MASK 0x8
>> enum EAV_PRESENT{
>> @@ -89,10 +87,8 @@ enum AT_MODE{
>> };
>>
>> #define PWR_SEL_MASK 0x40
>> -enum POWE_TYPE{
>> - SELF_POWER = 0x0, /* 0: self power */
>> - BUS_POWER = 0x40 /* 1: bus power */
>> -};
>> +#define SELF_POWER 0x0 /* 0: self power */
>> +#define BUS_POWER 0x40 /* 1: bus power */
>>
>> enum USB_POWE_TYPE{
>> USB_SELF_POWER = 0,
>>
>
> IMO keeping them into enums are a lot better than defines.
>
> Perhaps the right thing would be to join both enums here.

ORing enums is really not a good idea: you would normally never do that, and the
compiler warning is IMHO appropriate.

I think this is a good change and I plan to take this.

Regards,

Hans

>
>
> Thanks,
> Mauro
>