On Mon, May 25, 2020 at 03:54:00PM +0200, gregkh@xxxxxxxxxxxxxxxxxxx wrote:
The patch below does not apply to the 5.4-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@xxxxxxxxxxxxxxx>.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From b455d06e6fb3c035711e8aab1ca18082ccb15d87 Mon Sep 17 00:00:00 2001
From: Fabrice Gasnier <fabrice.gasnier@xxxxxx>
Date: Thu, 30 Apr 2020 11:28:46 +0200
Subject: [PATCH] iio: adc: stm32-dfsdm: fix device used to request dma
DMA channel request should use device struct from platform device struct.
Currently it's using iio device struct. But at this stage when probing,
device struct isn't yet registered (e.g. device_register is done in
iio_device_register). Since commit 71723a96b8b1 ("dmaengine: Create
symlinks between DMA channels and slaves"), a warning message is printed
as the links in sysfs can't be created, due to device isn't yet registered:
- Cannot create DMA slave symlink
- Cannot create DMA dma:rx symlink
Fix this by using device struct from platform device to request dma chan.
Fixes: eca949800d2d ("IIO: ADC: add stm32 DFSDM support for PDM microphone")
Signed-off-by: Fabrice Gasnier <fabrice.gasnier@xxxxxx>
Cc: <Stable@xxxxxxxxxxxxxxx>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx>
I've also grabbed a9ab624edd91 ("iio: adc: stm32-dfsdm: Use
dma_request_chan() instead dma_request_slave_channel()") and queued both
for 5.4 and 4.19.
--
Thanks,
Sasha
