Hi deee Ho Lee, On Wed, 2020-12-02 at 15:32 +0200, Matti Vaittinen wrote: > Hello Lee, > > On Wed, 2020-12-02 at 12:57 +0000, Lee Jones wrote: > > On Fri, 27 Nov 2020, Vaittinen, Matti wrote: > > > > > Hello Lee, > > > > > > On Fri, 2020-11-27 at 08:32 +0000, Lee Jones wrote: > > > > On Mon, 23 Nov 2020, Matti Vaittinen wrote: > > > > > > > > > Add core support for ROHM BD9576MUF and BD9573MUF PMICs which > > > > > are > > > > > mainly used to power the R-Car series processors. > > > > > > > > > > Signed-off-by: Matti Vaittinen < > > > > > matti.vaittinen@xxxxxxxxxxxxxxxxx> > > > > > --- > > > > > drivers/mfd/Kconfig | 11 ++++ > > > > > drivers/mfd/Makefile | 1 + > > > > > drivers/mfd/rohm-bd9576.c | 108 > > > > > +++++++++++++++++++++++++++++++ > > > > > include/linux/mfd/rohm-bd957x.h | 59 +++++++++++++++++ > > > > > include/linux/mfd/rohm-generic.h | 2 + > > > > > 5 files changed, 181 insertions(+) > > > > > create mode 100644 drivers/mfd/rohm-bd9576.c > > > > > create mode 100644 include/linux/mfd/rohm-bd957x.h > > > > > > > > Looks like a possible candidate for "simple-mfd-i2c". > > > > > > > > Could you look into that please? > > > > > > > I must admit I didn't know about "simple-mfd-i2c". Good thing to > > > know > > > when working with simple devices :) Is this a new thing? > > > > Yes, it's new. > > > > > I am unsure I understand the idea fully. Should users put all the > > > different regamp configs in this file and just add the device IDs > > > with > > > pointer to correct config? (BD9576 and BD9573 need volatile > > > ranges). > > > Also, does this mean each sub-device should have own node and own > > > compatible in DT to get correctly load and probed? I guess this > > > would > > > need a buy-in from Rob too then. > > > > You should describe the H/W in DT. > > Yes. And it is described. But I've occasionally received request from > DT guys to add some properties directly to MFD node and not to add > own > sub-node. This is what is done for example with the BD71837/47 clocks > - > there is no own node for clk - the clk properties are placed directly > in MFD node (as was requested by Stephen and Rob back then - I > originally had own node for clk). I really have no clear view on when > things warrant for own subnode and when they don't - but as far as I > can see using simple-mfd-i2c forces one to always have a sub-node / > device. Even just a empty node with nothing but the compatible even > if > device does not need stuff from DT? Anyways, I think this is nice > addition for simple drivers. > > > > By the way - for uneducated eyes like mine this does not look > > > like > > > it > > > has much to do with MFD as a device - here MFD reminds me of a > > > simple- > > > bus on top of I2C. > > > > This is for MFD devices where the parent does little more than > > create > > a shared address space for child devices to operate on - like > > yours. > > > > > Anyways, the BD9576 and BD9573 both have a few interrupts for > > > OVD/UVD > > > conditions and I am expecting that I will be asked to provide the > > > regulator notifiers for those. Reason why I omitted the IRQs for > > > now is > > > that the HW is designed to keep the IRQ asserted for whole error > > > duration so some delayed ack mechanism would be needed. I would > > > like to > > > keep the door open for adding IRQs to MFD core. > > > > You mean to add an IRQ Domain? > > Yes. I planned to use regmap-irq and create irq chip in MFD when the > over / under voltage / temperature - notifications or watchdog IRQs > are > needed. I am sorry if I have missed your reply. The ROHM email had redirected almost all patch emails to spam + I am not sure if some mails are dropping :( (I am considering moving to gmail - but I'd rather keep all mails in one system and I can't transfer work mail traffic to gmail... I wonder how others are managing the mails - which mail system you are using?) I think this series is now pending the decision how to proceed with MFD part. If you still want me to start with "simple-mfd-i2c", then I would appreciate if you pointed me how you would like to see the regmap configs added. Although I am quite positive this (eventually) ends up being more than what simple-mfd-i2c is intended for (because at some point people want to add the use of the interrupts). Best Regards Matti Vaittinen
