From: Jonathan Cameron <jic23@kernel.org>
To: Peter Ujfalusi <peter.ujfalusi@ti.com>
Cc: alexandre.torgue@st.com, linux-iio@vger.kernel.org,
linux-kernel@vger.kernel.org, vkoul@kernel.org,
mcoquelin.stm32@gmail.com,
Fabrice Gasnier <fabrice.gasnier@st.com>,
linux-stm32@st-md-mailman.stormreply.com,
linux-arm-kernel@lists.infradead.org
Subject: Re: [PATCH] iio: adc: stm32-adc: Use dma_request_chan() instead dma_request_slave_channel()
Date: Mon, 23 Dec 2019 15:42:30 +0000 [thread overview]
Message-ID: <20191223154230.7fb2a988@archlinux> (raw)
In-Reply-To: <20191217075153.23766-1-peter.ujfalusi@ti.com>
On Tue, 17 Dec 2019 09:51:53 +0200
Peter Ujfalusi <peter.ujfalusi@ti.com> wrote:
> dma_request_slave_channel() is a wrapper on top of dma_request_chan()
> eating up the error code.
>
> By using dma_request_chan() directly the driver can support deferred
> probing against DMA.
>
> Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Hi Peter,
Change looks sensible to me, but I'd like to leave a little longer
for others to look at this.
Give me a poke if I seem to have lost it by the end of the first
week in Jan.
Thanks,
Jonathan
> ---
> drivers/iio/adc/stm32-adc.c | 10 ++++++++--
> 1 file changed, 8 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/iio/adc/stm32-adc.c b/drivers/iio/adc/stm32-adc.c
> index 3b291d72701c..5dab23f1fdee 100644
> --- a/drivers/iio/adc/stm32-adc.c
> +++ b/drivers/iio/adc/stm32-adc.c
> @@ -1746,9 +1746,15 @@ static int stm32_adc_dma_request(struct iio_dev *indio_dev)
> struct dma_slave_config config;
> int ret;
>
> - adc->dma_chan = dma_request_slave_channel(&indio_dev->dev, "rx");
> - if (!adc->dma_chan)
> + adc->dma_chan = dma_request_chan(&indio_dev->dev, "rx");
> + if (IS_ERR(adc->dma_chan)) {
> + if (PTR_ERR(adc->dma_chan) == -EPROBE_DEFER)
> + return -EPROBE_DEFER;
> +
> + /* Ignore errors to fall back to IRQ mode */
> + adc->dma_chan = NULL;
> return 0;
> + }
>
> adc->rx_buf = dma_alloc_coherent(adc->dma_chan->device->dev,
> STM32_DMA_BUFFER_SIZE,
_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
next prev parent reply other threads:[~2019-12-23 15:42 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-12-17 7:51 [PATCH] iio: adc: stm32-adc: Use dma_request_chan() instead dma_request_slave_channel() Peter Ujfalusi
2019-12-23 15:42 ` Jonathan Cameron [this message]
2020-01-06 10:25 ` Fabrice Gasnier
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20191223154230.7fb2a988@archlinux \
--to=jic23@kernel.org \
--cc=alexandre.torgue@st.com \
--cc=fabrice.gasnier@st.com \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=linux-iio@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-stm32@st-md-mailman.stormreply.com \
--cc=mcoquelin.stm32@gmail.com \
--cc=peter.ujfalusi@ti.com \
--cc=vkoul@kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).