From: Ulf Hansson ulf.hansson@linaro.org
commit f458488425f1cc9a396aa1d09bb00c48783936da upstream.
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 | 1 + include/linux/amba/bus.h | 1 + 2 files changed, 2 insertions(+)
--- a/drivers/amba/bus.c +++ b/drivers/amba/bus.c @@ -645,6 +645,7 @@ static void amba_device_initialize(struc dev->dev.release = amba_device_release; dev->dev.bus = &amba_bustype; dev->dev.dma_mask = &dev->dev.coherent_dma_mask; + dev->dev.dma_parms = &dev->dma_parms; dev->res.name = dev_name(&dev->dev); }
--- a/include/linux/amba/bus.h +++ b/include/linux/amba/bus.h @@ -65,6 +65,7 @@ struct amba_device { struct device dev; struct resource res; struct clk *pclk; + struct device_dma_parameters dma_parms; unsigned int periphid; unsigned int cid; struct amba_cs_uci_id uci;