linux-kernel - Re: [PATCH v2 5/7] iio: adc: ad4170: Add GPIO controller support

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <CAHp75VfF2DJKghy47UP_GPtcfxKNFfJW2oWz4sUZ1XTCxOte9g@mail.gmail.com>
Date: Wed, 30 Apr 2025 01:14:16 +0300
From: Andy Shevchenko <andy.shevchenko@...il.com>
To: Marcelo Schmitt <marcelo.schmitt@...log.com>
Cc: linux-iio@...r.kernel.org, devicetree@...r.kernel.org, 
	linux-kernel@...r.kernel.org, jic23@...nel.org, lars@...afoo.de, 
	Michael.Hennerich@...log.com, dlechner@...libre.com, nuno.sa@...log.com, 
	andy@...nel.org, robh@...nel.org, krzk+dt@...nel.org, conor+dt@...nel.org, 
	marcelo.schmitt1@...il.com
Subject: Re: [PATCH v2 5/7] iio: adc: ad4170: Add GPIO controller support

On Mon, Apr 28, 2025 at 3:29 PM Marcelo Schmitt
<marcelo.schmitt@...log.com> wrote:
>
> The AD4170 has four multifunctional pins that can be used as GPIOs. The
> GPIO functionality can be accessed when the AD4170 chip is not busy
> performing continuous data capture or handling any other register
> read/write request. Also, the AD4170 does not provide any interrupt based
> on GPIO pin states so AD4170 GPIOs can't be used as interrupt sources.
>
> Implement gpio_chip callbacks to make AD4170 GPIO pins controllable through
> the gpiochip interface.

...

> +static int ad4170_gpio_set(struct gpio_chip *gc, unsigned int offset, int value)
> +{
> +       struct iio_dev *indio_dev = gpiochip_get_data(gc);
> +       struct ad4170_state *st = iio_priv(indio_dev);
> +       unsigned int val;
> +       int ret;
> +
> +       if (!iio_device_claim_direct(indio_dev))
> +               return -EBUSY;
> +
> +       guard(mutex)(&st->lock);
> +       ret = regmap_read(st->regmap, AD4170_GPIO_MODE_REG, &val);
> +       if (ret)
> +               goto err_release;
> +
> +       if (val & BIT(offset * 2 + 1))
> +               ret = regmap_update_bits(st->regmap, AD4170_GPIO_OUTPUT_REG,
> +                                        BIT(offset), value << offset);

Haven't you seen my previous review (v1)? I asked what if the value is > 1?
I also recommended looking at regmap_assign_bits().

> +       else
> +               ret = -EPERM;
> +
> +err_release:
> +       iio_device_release_direct(indio_dev);
> +       return ret;
> +}

-- 
With Best Regards,
Andy Shevchenko