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References: <20220111115919.14645-1-cristian.pop@analog.com> <20220111115919.14645-2-cristian.pop@analog.com>
In-Reply-To: <20220111115919.14645-2-cristian.pop@analog.com>
From:   Andy Shevchenko <andy.shevchenko@gmail.com>
Date:   Wed, 12 Jan 2022 17:23:31 +0200
Message-ID: <CAHp75VcE=Ac=DAJc2t2dp5G7CM_qRDKWencNiWmb_ijhHh4NBg@mail.gmail.com>
Subject: Re: [PATCH v2 2/2] one-bit-adc-dac: Add initial version of one bit ADC-DAC
To:     Cristian Pop <cristian.pop@analog.com>,
        Bartosz Golaszewski <brgl@bgdev.pl>
Cc:     linux-iio <linux-iio@vger.kernel.org>,
        "open list:GPIO SUBSYSTEM" <linux-gpio@vger.kernel.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Jonathan Cameron <jic23@kernel.org>,
        devicetree <devicetree@vger.kernel.org>,
        Rob Herring <robh+dt@kernel.org>
Content-Type: text/plain; charset="UTF-8"
Precedence: bulk

On Wed, Jan 12, 2022 at 11:50 AM Cristian Pop <cristian.pop@analog.com> wrote:
>
> This allows remote reading and writing of the GPIOs. This is useful in
> application that run on another PC, at system level, where multiple iio
> devices and GPIO devices are integrated together.

Should it be called GPIO-IIO proxy or something like that?

...

> +/*

> + * one-bit-adc-dac
> + *

These two lines make no sense.

> + * Copyright 2022 Analog Devices Inc.
> + */

...

> +enum ch_direction {
> +       CH_IN,
> +       CH_OUT,
> +};

How is it different from the corresponding GPIO flag?

...

> +static int one_bit_adc_dac_write_raw(struct iio_dev *indio_dev,
> +                           struct iio_chan_spec const *chan,
> +                           int val,
> +                           int val2,
> +                           long info)

Can be compressed to a fewer LOCs.

...

> +       return sprintf(label, "%s\n", st->labels[ch]);

In a few releases the sysfs_emit() is present and must be used.

...

> +       fwnode = dev_fwnode(device);

No need. See below.

...

> +       child_num = device_get_child_node_count(device);

Error checks?

...

> +       st->labels = devm_kzalloc(device, sizeof(*st->labels) * child_num, GFP_KERNEL);

You should use devm_kcalloc() instead, it does slightly more than
simple multiplication.

> +       if (!st->labels)
> +               return -ENOMEM;

...

> +       fwnode_for_each_child_node(fwnode, child) {

device_for_each_...

> +               if (fwnode_property_read_u32(child, "reg", &crt_ch))
> +                       continue;
> +
> +               if (crt_ch >= num_channels)
> +                       continue;
> +
> +               if (fwnode_property_read_string(child, "label", &label))
> +                       continue;
> +
> +               chan = &channels[crt_ch];
> +               st->labels[--i] = label;
> +       }

...

> +MODULE_LICENSE("Dual BSD/GPL");
> \ No newline at end of file

Aiaiai.

-- 
With Best Regards,
Andy Shevchenko