linux-kernel - Re: [PATCH RESEND v3 2/3] Input: aw86927

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Message-ID: <81822df8-1978-4f22-93e7-87b79e1fc9f3@oss.qualcomm.com>
Date: Thu, 25 Sep 2025 14:15:42 +0200
From: Konrad Dybcio <konrad.dybcio@....qualcomm.com>
To: Griffin Kroah-Hartman <griffin.kroah@...rphone.com>,
        Dmitry Torokhov <dmitry.torokhov@...il.com>,
        Rob Herring <robh@...nel.org>,
        Krzysztof Kozlowski <krzk+dt@...nel.org>,
        Conor Dooley
 <conor+dt@...nel.org>,
        Bjorn Andersson <andersson@...nel.org>,
        Konrad Dybcio <konradybcio@...nel.org>,
        Luca Weiss <luca.weiss@...rphone.com>
Cc: linux-input@...r.kernel.org, devicetree@...r.kernel.org,
        linux-kernel@...r.kernel.org, linux-arm-msm@...r.kernel.org
Subject: Re: [PATCH RESEND v3 2/3] Input: aw86927 - add driver for Awinic
 AW86927

On 9/25/25 12:07 PM, Griffin Kroah-Hartman wrote:
> Add support for the I2C-connected Awinic AW86927 LRA haptic driver.
> 
> This driver includes a hardcoded sine waveform to be uploaded to the
> AW86927's SRAM for haptic playback.
> This driver does not currently support all the capabilities of the
> AW86927, such as F0 calibration, RTP mode, and CONT mode.
> 
> Signed-off-by: Griffin Kroah-Hartman <griffin.kroah@...rphone.com>
> ---

I'll give you a couple of cosmetic comments, feel free to ignore

uint8_t is abbreviated as u8 in the kernel

[...]

> +#define AW86927_PLAYCFG1_BST_MODE_MASK		GENMASK(7, 7)

GENMASK(n, n) is BIT(n)

[...]

> +static int aw86927_wait_enter_standby(struct aw86927_data *haptics)
> +{
> +	unsigned int reg_val;
> +	int err;

"ret" is more common (for "return value")

[...]

> +	switch (play_mode) {
> +	case AW86927_STANDBY_MODE:
> +		/* Briefly toggle standby, then toggle back to standby off */
> +		err = regmap_update_bits(haptics->regmap,
> +				AW86927_SYSCTRL3_REG,
> +				AW86927_SYSCTRL3_STANDBY_MASK,
> +				FIELD_PREP(AW86927_SYSCTRL3_STANDBY_MASK,
> +					   AW86927_SYSCTRL3_STANDBY_ON));

this is regmap_set_bits(regmap, register, field), you can consider
dropping the _MASK suffix too

> +		if (err)
> +			return err;
> +
> +		err = regmap_update_bits(haptics->regmap,
> +				AW86927_SYSCTRL3_REG,
> +				AW86927_SYSCTRL3_STANDBY_MASK,
> +				FIELD_PREP(AW86927_SYSCTRL3_STANDBY_MASK,
> +					   AW86927_SYSCTRL3_STANDBY_OFF));

regmap_clear_bits()

(also regmap_assign_bits() which is a conditional version of the two
is a nice piece of syntax sugar)

Konrad