Hi Harsha, On Tue, Feb 27, 2018 at 7:29 AM, Harsha Rao <harshrao464@xxxxxxxxx> wrote: > On Tue, Feb 27, 2018 at 8:44 PM, Larry Finger <Larry.Finger@xxxxxxxxxxxx> wrote: >> On 02/27/2018 07:30 AM, Harsha Rao wrote: >>> >>> On Tue, Feb 27, 2018 at 4:45 PM, Arend van Spriel >>> <arend.vanspriel@xxxxxxxxxxxx> wrote: >>>> >>>> On 2/27/2018 11:16 AM, Harsha Rao wrote: >>>>> >>>>> >>>>> Hi folks, >>>>> I am developing a new wifi driver for our sdio based wifi device. >>>>> >>>>> I see that SDIO_VENDOR_ID and SDIO_DEVICE_ID for our device (We had >>>>> bought the SDIO IP from 3rd party) is already been used by some >>>>> other vendor and its already into staging . >>>>> >>>>> Please suggest me how can I move forward to submit the driver for >>>>> staging. >>>> >>>> >>>> >>>> Can you be more specific about the conflicting vendor id and device id? >>> >>> >>> Hi, >>> My driver kicks in with vendor id 0x296 and device id 0x5347. >>> But when I grepped the the kernel source I could see an other driver >>> wilc1000 using the same vendor ID and device ID >>> ( We have a different hw than them !) >>> >>>>> Is there a way to reconfigure the values in the SDIO host for >>>>> different value or does Linux allow two drivers with same values to >>>>> survive mutual exclusively >>>> >>>> >>>> >>>> First come first serve. When a device is detected, the driver core looks >>>> for >>>> drivers supporting it based on device table and the first that >>>> successfully >>>> returns from the .probe() callback is bound to the device. >>>> >>>> Regards, >>>> Arend >>> >>> >>> Does Linux allow two drivers with conflicting device and vendor IDs to >>> stay on in kernel ? >> >> >> Yes. We have a similar situation with the rtl8192e driver in staging and the >> rtl8192se driver in the wireless tree, which share PCI ID 0bda:8192. Our >> solution was to insert code in the probe routine that tests some value in >> addition to the PCI ID. In our case, that was the PCI revision id. Line 2496 >> of file drivers/staging/rtl8192e/rtl8192e/rtl_core.c shows the test in the >> staging driver. >> >> The downsides of this unfortunate duplication are that if the wrong driver >> loads first, then it remains loaded, you will need to cooperate with the >> maintainer of the other driver to insert the extra detection code, and you >> may need to do quite a bit of processing to be able to determine whether you >> have the correct device. >> >> Larry >> As both Larry and Arend mention, while it's possible to have multiple drivers with the same IDs, for obvious reasons it's not desirable. In theory the vendor IDs shouldn't be duplicated on fundamentally different devices, assuming that the manufacturers are doing things "right". The VID is paid for by buying it from the SD Association. My suspicion is that your device, is fundamentally a wilc1000 and that the existing wilc1000 driver will likely largely work for it and all you really need to do is modify the existing driver to handle the quirks of your particular implementation of the wilc1000 chip. And, often WiFi chips will let you change the VID/PID somewhere within whatever non-volatile storage it has (like where it stores the MAC address).
