[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <2df46968-ff5f-43bc-98fd-506840c1aaa9@baylibre.com>
Date: Mon, 3 Jun 2024 11:00:12 -0500
From: David Lechner <dlechner@...libre.com>
To: "Ceclan, Dumitru" <mitrutzceclan@...il.com>,
Nuno Sá <noname.nuno@...il.com>,
Jonathan Cameron <jic23@...nel.org>,
Dumitru Ceclan via B4 Relay <devnull+dumitru.ceclan.analog.com@...nel.org>
Cc: dumitru.ceclan@...log.com, Lars-Peter Clausen <lars@...afoo.de>,
Michael Hennerich <Michael.Hennerich@...log.com>,
Rob Herring <robh@...nel.org>,
Krzysztof Kozlowski <krzysztof.kozlowski+dt@...aro.org>,
Conor Dooley <conor+dt@...nel.org>, linux-iio@...r.kernel.org,
devicetree@...r.kernel.org, linux-kernel@...r.kernel.org
Subject: Re: [PATCH v4 3/6] iio: adc: ad7173: refactor ain and vref selection
On 6/3/24 8:08 AM, Ceclan, Dumitru wrote:
> On 03/06/2024 16:00, Nuno Sá wrote:
>> On Sat, 2024-06-01 at 19:49 +0100, Jonathan Cameron wrote:
>>> On Fri, 31 May 2024 22:42:29 +0300
>>> Dumitru Ceclan via B4 Relay <devnull+dumitru.ceclan.analog.com@...nel.org> wrote:
>>>
>>>> From: Dumitru Ceclan <dumitru.ceclan@...log.com>
>>>>
>>>> Move validation of analog inputs and reference voltage selection to
>>>> separate functions to reduce the size of the channel config parsing
>>>> function and improve readability.
>>>> Add defines for the number of analog inputs in a channel.
>>>>
>>>> Reviewed-by: David Lechner <dlechner@...libre.com>
>>>> Signed-off-by: Dumitru Ceclan <dumitru.ceclan@...log.com>
>>>> ---
>>>> drivers/iio/adc/ad7173.c | 71 ++++++++++++++++++++++++++++++++++--------------
>>>> 1 file changed, 50 insertions(+), 21 deletions(-)
>>>>
>>>> diff --git a/drivers/iio/adc/ad7173.c b/drivers/iio/adc/ad7173.c
>>>> index 6e249628bc64..a20831d99aa5 100644
>>>> --- a/drivers/iio/adc/ad7173.c
>>>> +++ b/drivers/iio/adc/ad7173.c
>>>> @@ -60,6 +60,7 @@
>>>> #define AD7173_CH_SETUP_AINPOS_MASK GENMASK(9, 5)
>>>> #define AD7173_CH_SETUP_AINNEG_MASK GENMASK(4, 0)
>>>>
>>>> +#define AD7173_NO_AINS_PER_CHANNEL 2
>>>> #define AD7173_CH_ADDRESS(pos, neg) \
>>>> (FIELD_PREP(AD7173_CH_SETUP_AINPOS_MASK, pos) | \
>>>> FIELD_PREP(AD7173_CH_SETUP_AINNEG_MASK, neg))
>>>> @@ -623,6 +624,7 @@ static int ad7173_setup(struct iio_dev *indio_dev)
>>>> static unsigned int ad7173_get_ref_voltage_milli(struct ad7173_state *st,
>>>> u8 reference_select)
>>>> {
>>>> + struct device *dev = &st->sd.spi->dev;
>>>> int vref;
>>>>
>>>> switch (reference_select) {
>>>> @@ -646,9 +648,11 @@ static unsigned int ad7173_get_ref_voltage_milli(struct
>>>> ad7173_state *st,
>>>> return -EINVAL;
>>>> }
>>>>
>>>> - if (vref < 0)
>>>> + if (vref < 0) {
>>>> + dev_err(dev, "Cannot use reference %u. Error:%d\n",
>>>> + reference_select, vref);
>>>> return vref;
>>>> -
>>>> + }
>>>> return vref / (MICRO / MILLI);
>>>> }
>>>>
>>>> @@ -905,13 +909,50 @@ static int ad7173_register_clk_provider(struct iio_dev
>>>> *indio_dev)
>>>> &st->int_clk_hw);
>>>> }
>>>>
>>>> +static int ad7173_validate_voltage_ain_inputs(struct ad7173_state *st,
>>>> + const unsigned int
>>>> ain[AD7173_NO_AINS_PER_CHANNEL])
>>> I was late to the game in replying to previous thread.
>>>
>>> This is neater without the loop and with 2 parameters. Anyhow see reply to v3.
>>>
>>
>> Yeps, even more given that we're passing/copying the complete array which always
>> fells awkward to me :)
>>
>> - Nuno Sá
>>
>>
>
> I rewrote the function, but it feels a bit awkward, perhaps I could get a bit of
> advice before sending V5:
Maybe we could make this easier to read with macros?
>
> static int ad7173_validate_voltage_ain_inputs(struct ad7173_state *st,
> unsigned int ain0, unsigned int ain1)
> {
> struct device *dev = &st->sd.spi->dev;
> bool special_input0, special_input1;
>
> special_input0 = ain0 == AD7173_AIN_REF_POS || ain0 == AD7173_AIN_REF_NEG ||
> ((ain0 == AD7173_AIN_COM_IN_POS || ain0 == AD7173_AIN_COM_IN_NEG) &&
> (st->info->has_common_input)) || ain0 == AD4111_VINCOM_INPUT;
> special_input1 = (ain1 == AD7173_AIN_REF_POS || ain1 == AD7173_AIN_REF_NEG) ||
> ((ain1 == AD7173_AIN_COM_IN_POS || ain1 == AD7173_AIN_COM_IN_NEG) &&
> (st->info->has_common_input)) || ain1 == AD4111_VINCOM_INPUT;
>
special_input0 = AD7173_IS_SPECIAL_INPUT(ain0);
special_input1 = AD7173_IS_SPECIAL_INPUT(ain1);
> if (st->info->has_vincom_input) {
> if (ain0 == AD4111_VINCOM_INPUT &&
> ain1 < st->info->num_voltage_in && /* Normal input */
> ain1 >= st->info->num_voltage_in_div) /* Input without divider */
> return dev_err_probe(dev, -EINVAL,
> "VINCOM must be paired with inputs having divider.\n");
>
> if (ain1 == AD4111_VINCOM_INPUT &&
> ain0 < st->info->num_voltage_in && /* Normal input */
> ain0 >= st->info->num_voltage_in_div) /* Input without divider */
> return dev_err_probe(dev, -EINVAL,
> "VINCOM must be paired with inputs having divider.\n");
if (AD7173_IS_VINCOM_MISMATCH(ain0, ain1) ||
AD7173_IS_VINCOM_MISMATCH(ain1, ain0)) {
return dev_err_probe(dev, -EINVAL,
"VINCOM must be paired with inputs having divider.\n");
> }
>
> if ((ain0 >= st->info->num_voltage_in && !special_input0) ||
> (ain1 >= st->info->num_voltage_in && !special_input1))
> return dev_err_probe(dev, -EINVAL,
> "Input pin number out of range for pair (%d %d).\n",
> ain0, ain1);
>
> if (!special_input0 && !special_input1 &&
> ((ain0 >= st->info->num_voltage_in_div) !=
> (ain1 >= st->info->num_voltage_in_div)))
> return dev_err_probe(dev, -EINVAL,
> "Both inputs must either have a voltage divider or not have: (%d %d).\n",
> ain0, ain1);
These last two don't seem so bad.
>
> return 0;
> }
>
> It feels a bit too verbose, but I could not come up with a better way to
> incorporate all those cases.
Powered by blists - more mailing lists