amba: Initialize dma_parms for amba devices
authorUlf Hansson <ulf.hansson@linaro.org>
Wed, 22 Apr 2020 10:10:13 +0000 (12:10 +0200)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Tue, 28 Apr 2020 15:44:34 +0000 (17:44 +0200)
commitf458488425f1cc9a396aa1d09bb00c48783936da
tree7ca42d6ede622708b91422215ecdc67bb2da4e24
parent9495b7e92f716ab2bd6814fab5e97ab4a39adfdd
amba: Initialize dma_parms for amba devices

It's currently the amba driver's responsibility to initialize the pointer,
dma_parms, for its corresponding struct device. The benefit with this
approach allows us to avoid the initialization and to not waste memory for
the struct device_dma_parameters, as this can be decided on a case by case
basis.

However, it has turned out that this approach is not very practical. Not
only does it lead to open coding, but also to real errors. In principle
callers of dma_set_max_seg_size() doesn't check the error code, but just
assumes it succeeds.

For these reasons, let's do the initialization from the common amba bus at
the device registration point. This also follows the way the PCI devices
are being managed, see pci_device_add().

Suggested-by: Christoph Hellwig <hch@lst.de>
Cc: Russell King <linux@armlinux.org.uk>
Cc: <stable@vger.kernel.org>
Tested-by: Haibo Chen <haibo.chen@nxp.com>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20200422101013.31267-1-ulf.hansson@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/amba/bus.c
include/linux/amba/bus.h