Re: [PATCH V9 3/3] Input: new da7280 haptic driver

From: Uwe Kleine-König
Date: Sun Mar 01 2020 - 16:20:57 EST


Hello Roy,

On Sat, Feb 29, 2020 at 12:59:20AM +0000, Roy Im wrote:
> Okay, thanks. I have tried to update that as below.
> Could I get your comment if you still see anything on this?
>
> /* Maximum gain is 0x7fff for PWM mode */
> #define MAX_MAGNITUDE_SHIFT 15
> [...]
> period_mag_multi >>= MAX_MAGNITUDE_SHIFT;
>
> /* The interpretation of duty cycle depends on the acc_en,
> * it should be from 50% to 100% for acc_en = 0.
> * See datasheet 'PWM mode' section for more details.
> */
> if (!haptics->acc_en) {
> period_mag_multi += state.period;
> period_mag_multi /= 2;
> }

Much better. Extra points if you add a link to the datasheet at the
top of the driver. I didn't look at the datasheet and assume that the
reasoning is obvious then.

Best regards
Uwe

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