Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
Message-ID: <82ec09fd-a940-cae6-f793-1bb903190664@baylibre.com>
Date:   Tue, 6 Sep 2022 16:41:16 +0200
MIME-Version: 1.0
User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101
 Thunderbird/102.2.1
Subject: Re: [RFC PATCH 2/2] counter: Introduce the COUNTER_COMP_ARRAY_U64
 component type
Content-Language: en-US
To:     William Breathitt Gray <william.gray@linaro.org>,
        linux-iio@vger.kernel.org
Cc:     linux-kernel@vger.kernel.org, mranostay@ti.com,
        fabien.lahoudere@collabora.com, gwendal@chromium.org,
        enric.balletbo@collabora.com, bleung@chromium.org,
        groeck@chromium.org, jic23@kernel.org, david@lechnology.com,
        robertcnelson@gmail.com
References: <cover.1661785438.git.william.gray@linaro.org>
 <31a35481813ec26949018888253278a634998a92.1661785438.git.william.gray@linaro.org>
From:   Julien Panis <jpanis@baylibre.com>
In-Reply-To: <31a35481813ec26949018888253278a634998a92.1661785438.git.william.gray@linaro.org>
Content-Type: text/plain; charset=UTF-8; format=flowed
Content-Transfer-Encoding: 8bit
Precedence: bulk


On 29/08/2022 17:17, William Breathitt Gray wrote:
> The COUNTER_COMP_ARRAY_U64 Counter component type is introduced to
> enable support for Counter array components. With Counter array
> components, exposure for buffers on counter devices can be defined via
> new Counter array component macros. This should simplify code for driver
> authors who would otherwise need to define individual Counter components
> for each array element.
>
> Three Counter array component macros are introduced::
>
>          COUNTER_COMP_DEVICE_ARRAY_U64(_name, _read, _write, _length)
>          COUNTER_COMP_COUNT_ARRAY_U64(_name, _read, _write, _length)
>          COUNTER_COMP_SIGNAL_ARRAY_U64(_name, _read, _write, _length)

Hi William,

I have 2 comments :

1) What about ENUM ? I guess that it will not be possible to handle 
ARRAY of ENUM ?
     That would be useful for polarity0/1/2/3 in my ECAP driver
     (something like COUNTER_COMP_SIGNAL_ARRAY_ENUM for instance)

2) I made some tests with COUNTER_COMP_COUNT_ARRAY_U64
         COUNTER_COMP_COUNT_ARRAY_U64("capture", ecap_cnt_cap_read, 
NULL, ECAP_NB_CEVT)
     I can get consistent data value when using 'cat captureX' linux 
commands.
     But I get weird values when using watches from userspace 
application code (I will send my test results to you).

Julien Panis