Hi, > Am 10.05.2022 um 04:29 schrieb Zhou Yanjie <zhouyanjie@xxxxxxxxxxxxxx>: > > Hi Nikolaus, > > On 2022/5/10 上午4:19, H. Nikolaus Schaller wrote: >> Hi, >> >>> Am 09.05.2022 um 20:41 schrieb Zhou Yanjie <zhouyanjie@xxxxxxxxxxxxxx>: >>> >>> Hi Paul, >>> >>> On 2022/5/10 上午2:13, Paul Cercueil wrote: >>>> I can't say for sure that it's your problem, but your bluetooth nodes are missing "reg" properties. >>> >>> Unfortunately it doesn't seem to be the problem here, I added "reg" and >>> the problem persists, and I've looked at other device trees that contain >>> "brcm,bcm43438-bt", none of them use "reg", and "reg" is not mentioned in >>> neither "Documentation/devicetree/bindings/serial/nxp,sc16is7xx.txt" nor >>> "Documentation/devicetree/bindings/net/broadcom-bluetooth.yaml". >> what happens if you remove the serdev children from DTS? Does the driver create two separate /dev/tty ports? And do they work? > > > Yes, there will be two separate /dev/tty ports (ttySC0 and ttySC1), and > both ports can work normally, but at this time the two bluetooth modules > are not working. > > I guess it is because the driver does not detect bluetooth module nodes, > so the inability to operate "reset-gpios" and "device-wakeup-gpios" causes > the bluetooth module to work incorrectly. I would assume that it is not prepared to handle two serdev subnodes and assign the right gpios. > > >> >> Maybe the sc16is752 driver does not separate them for child nodes, i.e. while "reg" should be added it may not be handled? > > > I'm not too sure, I'm not very familiar with serial port systems. > If the truth is what you think, how should I improve it? Unfortunately I also don't know how the serdev implementation really works. It was my nagging to make it happen by persistently proposing a non-universal solutionsome years ago until one of the maintainers had mercy to write a general solution. So I could switch my driver to simply use the serdev API. It was for a GPS client device but not a tty side driver. I think if you look up the first patches for the serdev interface this should reveal the original author an he should be able to help. BR, Nikolaus
