On 04-07-21, 22:45, Kelvin Cheung wrote: > Vinod Koul <vkoul@xxxxxxxxxx> 于2021年6月7日周一 下午7:07写道: > > > > On 21-05-21, 07:02, Keguang Zhang wrote: > > > > > +config LOONGSON1_DMA > > > + tristate "Loongson1 DMA support" > > > + depends on MACH_LOONGSON32 > > > > Why does it have to do that? The dma driver is generic.. > > This driver is only available for LOONGSON32 CPUs. the underlaying firmware would ensure this driver is probed if you have such a device, so why have this restriction? > > > +static struct platform_driver ls1x_dma_driver = { > > > + .probe = ls1x_dma_probe, > > > + .remove = ls1x_dma_remove, > > > + .driver = { > > > + .name = "ls1x-dma", > > > + }, > > > > No device tree? > > Because the LOONGSON32 platform doesn't support DT yet. Okay so how is the platform device created? -- ~Vinod