On Thu, Mar 09, 2023 at 05:31:44PM +0800, Ye, Xiang wrote: > On Thu, Mar 09, 2023 at 08:52:24AM +0100, Greg Kroah-Hartman wrote: > > On Thu, Mar 09, 2023 at 03:10:56PM +0800, Ye Xiang wrote: > > > +static int ljca_mng_get_version(struct ljca_stub *stub, char *buf) > > > +{ > > > + struct fw_version version = {}; > > > + unsigned int len = sizeof(version); > > > + int ret; > > > + > > > + ret = ljca_stub_write(stub, LJCA_MNG_GET_VERSION, NULL, 0, &version, &len, true, > > > + LJCA_USB_WRITE_ACK_TIMEOUT_MS); > > > + if (ret) > > > + return ret; > > > + > > > + if (len != sizeof(version)) { > > > + dev_err(&stub->intf->dev, "get version failed, len:%d\n", len); > > > + return -EINVAL; > > > + } > > > + > > > + return sysfs_emit(buf, "%d.%d.%d.%d\n", version.major, version.minor, > > > + le16_to_cpu(version.patch), le16_to_cpu(version.build)); > > > +} > > > > You have sysfs files, yet no Documentation/ABI/ entries? That's not > > allowed, you know this :( > The Documentation/ABI/ entries is added for the sysfs on patch 5 of this series. > https://patchwork.kernel.org/project/linux-usb/patch/20230309071100.2856899-6-xiang.ye@xxxxxxxxx/ Ah, missed that, sorry. > > > > > +static ssize_t cmd_store(struct device *dev, struct device_attribute *attr, const char *buf, > > > + size_t count) > > > +{ > > > + struct usb_interface *intf = to_usb_interface(dev); > > > + struct ljca_dev *ljca_dev = usb_get_intfdata(intf); > > > + struct ljca_stub *mng_stub = ljca_stub_find(ljca_dev, LJCA_MNG_STUB); > > > + struct ljca_stub *diag_stub = ljca_stub_find(ljca_dev, LJCA_DIAG_STUB); > > > + > > > + if (sysfs_streq(buf, "dfu")) > > > + ljca_mng_set_dfu_mode(mng_stub); > > > + else if (sysfs_streq(buf, "debug")) > > > + ljca_diag_set_trace_level(diag_stub, 3); > > > > Sorry, but no, you can't do this in a sysfs file. > Do you mean that we can't use sysfs to send "debug" command to device? That is correct, use the kernel-wide debugging facilities that we have for this NEVER create your own custom interface just for one tiny driver, that is not allowed. > Could you provide some detail or hints? dev_dbg(). thanks, greg k-h