| Message ID | cover.1666786471.git.matthias.schiffer@ew.tq-group.com |
|---|---|
| Headers | show |
| Series | "notify-device" for cross-driver readiness notification | expand |
On 26/10/2022 09:15, Matthias Schiffer wrote: > Signed-off-by: Matthias Schiffer <matthias.schiffer@ew.tq-group.com> > --- > drivers/bluetooth/hci_mrvl.c | 17 +++++++++++++++++ > 1 file changed, 17 insertions(+) > > diff --git a/drivers/bluetooth/hci_mrvl.c b/drivers/bluetooth/hci_mrvl.c > index b7d764e6010f..dc55053574a9 100644 > --- a/drivers/bluetooth/hci_mrvl.c > +++ b/drivers/bluetooth/hci_mrvl.c > @@ -12,6 +12,7 @@ > #include <linux/skbuff.h> > #include <linux/firmware.h> > #include <linux/module.h> > +#include <linux/notify-device.h> > #include <linux/tty.h> > #include <linux/of.h> > #include <linux/of_device.h> > @@ -433,9 +434,25 @@ static int mrvl_serdev_probe(struct serdev_device *serdev) > return -ENOMEM; > > if (IS_ENABLED(CONFIG_OF)) { > + struct device_node *firmware_ready_node; > + struct device *firmware_ready; > + > mrvldev->info = of_device_get_match_data(&serdev->dev); > if (!mrvldev->info) > return -ENODEV; > + > + firmware_ready_node = of_parse_phandle(serdev->dev.of_node, > + "firmware-ready", 0); So you want us to go through five patches, find properties and OF-code, create in our minds bindings you think about and comment on that imaginary bindings. I think it should work otherwise - send bindings for all of your DT properties. Best regards, Krzysztof
This patch series is obviously missing documentation, MAINTAINERS entries, etc., but I'd like to solicit some basic feedback on whether this approach makes sense at all before I proceed. If it does, the naming is also very much open for bikeshedding - I'm not too happy with "notify-device". The basic problem that the notify-device tries to solve is the synchronization of firmware loading readiness between the Marvell/NXP WLAN and Bluetooth drivers, but it may also be applicable to other drivers. The WLAN and Bluetooth adapters are handled by separate drivers, and may be connected to the CPU using different interfaces (for example SDIO for WLAN and UART for Bluetooth). However, both adapters share a single firmware that may be uploaded via either interface. For the SDIO+UART case, uploading the firmware via SDIO is usually preferable, but even when the interface doesn't matter, it seems like a good idea to clearly define which driver should handle it. To avoid making the Bluetooth driver more complicated than necessary in this case, we'd like to defer the probing of the driver until the firmware is ready. For this purpose, we are introducing a notify-device, with the following properties: - The device is created by a driver as soon as some "readiness condition" is satisfied - Creating the device also binds a stub driver, so deferred probes are triggered - Looking up the notify device is possible via OF node / phandle reference This approach avoids a hard dependency between the WLAN and Bluetooth driver, and works regardless of the driver load order. The first patch implementes the notify-device driver itself, and the rest shows how the device could be hooked up to the mwifiex and hci_mrvl drivers. A device tree making use of the notify-device could look like the following: &sdhci1 { wifi@1 { compatible = "marvell,sd8987"; reg = <1>; wifi_firmware: firmware-notifier {}; }; }; &main_uart3 { bluetooth { compatible = "marvell,sd8987-bt"; firmware-ready = <&wifi_firmware>; }; }; Matthias Schiffer (5): misc: introduce notify-device driver wireless: mwifiex: signal firmware readiness using notify-device bluetooth: hci_mrvl: select firmwares to load by match data bluetooth: hci_mrvl: add support for SD8987 bluetooth: hci_mrvl: allow waiting for firmware load using notify-device drivers/bluetooth/hci_mrvl.c | 77 ++++++++++++-- drivers/misc/Kconfig | 4 + drivers/misc/Makefile | 1 + drivers/misc/notify-device.c | 109 ++++++++++++++++++++ drivers/net/wireless/marvell/mwifiex/main.c | 14 +++ drivers/net/wireless/marvell/mwifiex/main.h | 1 + include/linux/notify-device.h | 33 ++++++ 7 files changed, 228 insertions(+), 11 deletions(-) create mode 100644 drivers/misc/notify-device.c create mode 100644 include/linux/notify-device.h