Re: [PATCH v4 6/7] IIO: add STM32 timer trigger driver

From: Lee Jones
Date: Wed Dec 07 2016 - 05:47:02 EST


On Tue, 06 Dec 2016, Benjamin Gaignard wrote:

> [snip]
> >> +
> >> +static const char * const triggers0[] = {
> >> + TIM1_TRGO, TIM1_CH1, TIM1_CH2, TIM1_CH3, TIM1_CH4, NULL,
> >> +};
> >> +
> >> +static const char * const triggers1[] = {
> >> + TIM2_TRGO, TIM2_CH1, TIM2_CH2, TIM2_CH3, TIM2_CH4, NULL,
> >> +};
> >> +
> >> +static const char * const triggers2[] = {
> >> + TIM3_TRGO, TIM3_CH1, TIM3_CH2, TIM3_CH3, TIM3_CH4, NULL,
> >> +};
> >> +
> >> +static const char * const triggers3[] = {
> >> + TIM4_TRGO, TIM4_CH1, TIM4_CH2, TIM4_CH3, TIM4_CH4, NULL,
> >> +};
> >> +
> >> +static const char * const triggers4[] = {
> >> + TIM5_TRGO, TIM5_CH1, TIM5_CH2, TIM5_CH3, TIM5_CH4, NULL,
> >> +};
> >> +
> >> +static const char * const triggers5[] = {
> >> + TIM6_TRGO, NULL,
> >> +};
> >> +
> >> +static const char * const triggers6[] = {
> >> + TIM7_TRGO, NULL,
> >> +};
> >> +
> >> +static const char * const triggers7[] = {
> >> + TIM8_TRGO, TIM8_CH1, TIM8_CH2, TIM8_CH3, TIM8_CH4, NULL,
> >> +};
> >> +
> >> +static const char * const triggers8[] = {
> >> + TIM9_TRGO, TIM9_CH1, TIM9_CH2, NULL,
> >> +};
> >> +
> >> +static const char * const triggers9[] = {
> >> + TIM12_TRGO, TIM12_CH1, TIM12_CH2, NULL,
> >> +};
> >> +
> >> +static const void *triggers_table[] = {
> >> + triggers0,
> >> + triggers1,
> >> + triggers2,
> >> + triggers3,
> >> + triggers4,
> >> + triggers5,
> >> + triggers6,
> >> + triggers7,
> >> + triggers8,
> >> + triggers9,
> >> +};
> >
> > What about:
> >
> > static const char * const triggers[][] = {
> > { TIM1_TRGO, TIM1_CH1, TIM1_CH2, TIM1_CH3, TIM1_CH4, NULL },
> > { TIM2_TRGO, TIM2_CH1, TIM2_CH2, TIM2_CH3, TIM2_CH4, NULL },
> > { TIM3_TRGO, TIM3_CH1, TIM3_CH2, TIM3_CH3, TIM3_CH4, NULL },
> > { TIM4_TRGO, TIM4_CH1, TIM4_CH2, TIM4_CH3, TIM4_CH4, NULL },
> > { TIM5_TRGO, TIM5_CH1, TIM5_CH2, TIM5_CH3, TIM5_CH4, NULL },
> > { TIM6_TRGO, NULL },
> > { TIM7_TRGO, NULL },
> > { TIM8_TRGO, TIM8_CH1, TIM8_CH2, TIM8_CH3, TIM8_CH4, NULL },
> > { TIM9_TRGO, TIM9_CH1, TIM9_CH2, NULL },
> > { TIM12_TRGO, TIM12_CH1, TIM12_CH2, NULL }
> > };
>
> I can't because the second dimension of the array isn't fix.
> I could have between 2 and 6 elements per row... to create a dual dimension
> array I would have to add NULL entries like that:
>
> #define MAX_TRIGGERS 6
>
> static const void *triggers_table[][MAX_TRIGGERS] = {
> { TIM1_TRGO, TIM1_CH1, TIM1_CH2, TIM1_CH3, TIM1_CH4, NULL,},
> { TIM2_TRGO, TIM2_CH1, TIM2_CH2, TIM2_CH3, TIM2_CH4, NULL,},
> { TIM3_TRGO, TIM3_CH1, TIM3_CH2, TIM3_CH3, TIM3_CH4, NULL,},
> { TIM4_TRGO, TIM4_CH1, TIM4_CH2, TIM4_CH3, TIM4_CH4, NULL,},
> { TIM5_TRGO, TIM5_CH1, TIM5_CH2, TIM5_CH3, TIM5_CH4, NULL,},
> { TIM6_TRGO, NULL, NULL, NULL, NULL, NULL,},
> { TIM7_TRGO, NULL, NULL, NULL, NULL, NULL,},
> { TIM8_TRGO, TIM8_CH1, TIM8_CH2, TIM8_CH3, TIM8_CH4, NULL,},
> { TIM9_TRGO, TIM9_CH1, TIM9_CH2, NULL, NULL, NULL,},
> { TIM12_TRGO, TIM12_CH1, TIM12_CH2, NULL, NULL, NULL,},
> };

It was just an idea, not a tested implementation.

I don't understand why you have to pad with NULLs, but either way, it
looks much better than before and saves lots of lines of code.

> >> +static const char * const valids0[] = {
> >> + TIM5_TRGO, TIM2_TRGO, TIM4_TRGO, TIM3_TRGO, NULL,
> >> +};
> >> +
> >> +static const char * const valids1[] = {
> >> + TIM1_TRGO, TIM8_TRGO, TIM3_TRGO, TIM4_TRGO, NULL,
> >> +};
> >> +
> >> +static const char * const valids2[] = {
> >> + TIM1_TRGO, TIM8_TRGO, TIM5_TRGO, TIM4_TRGO, NULL,
> >> +};
> >> +
> >> +static const char * const valids3[] = {
> >> + TIM1_TRGO, TIM2_TRGO, TIM3_TRGO, TIM8_TRGO, NULL,
> >> +};
> >> +
> >> +static const char *const valids4[] = {
> >> + TIM2_TRGO, TIM3_TRGO, TIM4_TRGO, TIM8_TRGO, NULL,
> >> +};
> >> +
> >> +static const char * const valids7[] = {
> >> + TIM1_TRGO, TIM2_TRGO, TIM4_TRGO, TIM5_TRGO, NULL,
> >> +};
> >> +
> >> +static const char * const valids8[] = {
> >> + TIM2_TRGO, TIM3_TRGO, NULL,
> >> +};
> >> +
> >> +static const char * const valids9[] = {
> >> + TIM4_TRGO, TIM5_TRGO, NULL,
> >> +};
> >> +
> >> +static const void *valids_table[] = {
> >> + valids0,
> >> + valids1,
> >> + valids2,
> >> + valids3,
> >> + valids4,
> >> + NULL,
> >> + NULL,
> >> + valids7,
> >> + valids8,
> >> + valids9,
> >> +};
> >
> > Same here.
> >

--
Lee Jones
Linaro STMicroelectronics Landing Team Lead
Linaro.org â Open source software for ARM SoCs
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