On Wed, 7 Feb 2024 at 11:08, Abel Vesa <abel.vesa@xxxxxxxxxx> wrote: > > On 24-02-07 09:23:09, Dmitry Baryshkov wrote: > > On Wed, 7 Feb 2024 at 09:19, Abel Vesa <abel.vesa@xxxxxxxxxx> wrote: > > > > > > On 24-02-07 01:55:39, Dmitry Baryshkov wrote: > > > > On Wed, 7 Feb 2024 at 01:34, Abel Vesa <abel.vesa@xxxxxxxxxx> wrote: > > > > > > > > > > Some newer SPMI controllers support multiple bus masters. > > > > > Such a master can control multiple slave devices. The generic > > > > > framework needs to be able to pass on the master id to the > > > > > controller-specific driver. So do that. The framework will > > > > > check if the devicetree child nodes are actually bus masters > > > > > and will register the devices for each master. The legacy > > > > > approach will still be supported for backwards compatibility. > > > > > > > > Please remind me, are those two actual bus musters driving a single > > > > bus in parallel or two SPMI buses being handled by a single device? In > > > > the latter case this implementation is incorrect. There should be > > > > multiple spmi_controller instances, one for each bus. Allocate them in > > > > a loop and set ctrl->dev.of_node after allocating. > > > > > > It's two SPMI buses (two sets of wires) handled by the same controller, > > > HW-wise. > > > > > > If we register two spmi controllers with the kernel framework, it will > > > be HW inaccurate, because there is just one controller which has > > > multiple masters. > > > > struct spmi_controller is a controller for a single bus. Inside your > > device you have two SPMI buses, each can be controlled by its own > > struct spmi_controller. Just like devices that control multiple I2C, > > SPI or USB busses register a separate instance of the bus controller. > > Well, this is what this patchset is trying to do in the generic part. > The SPMI controller supports multiple buses (HW-wise) and therefore SW > implementation shouldn't be tied to single bus requirement. SPMI controller doesn't support multiple buses. You have a device which has two SPMI controllers inside. Just like all multi-bus controllers. > > > > > > > > > I'm not saying it might not work. But, to me, it looks more like a hack. > > > > > > Basically, we would be mapping HW bus masters to kernel controllers. > > > > Buses, not just masters. > > > > > > > > > > > > > > > > > > > Signed-off-by: Abel Vesa <abel.vesa@xxxxxxxxxx> > > > > > --- > > > > > drivers/spmi/spmi-mtk-pmif.c | 6 ++-- > > > > > drivers/spmi/spmi-pmic-arb.c | 10 +++--- > > > > > drivers/spmi/spmi.c | 76 ++++++++++++++++++++++++++++++-------------- > > > > > include/linux/spmi.h | 10 +++--- > > > > > 4 files changed, 67 insertions(+), 35 deletions(-) > > > > > > > > -- > > > > With best wishes > > > > Dmitry > > > > > > > > -- > > With best wishes > > Dmitry -- With best wishes Dmitry
