Date:   Thu, 9 Mar 2023 17:31:44 +0800
From:   "Ye, Xiang" <xiang.ye@intel.com>
To:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>
CC:     Arnd Bergmann <arnd@arndb.de>,
        Matthias Kaehlcke <mka@chromium.org>,
        "Lee Jones" <lee@kernel.org>, Wolfram Sang <wsa@kernel.org>,
        Tyrone Ting <kfting@nuvoton.com>,
        Mark Brown <broonie@kernel.org>,
        Linus Walleij <linus.walleij@linaro.org>,
        Bartosz Golaszewski <brgl@bgdev.pl>,
        <linux-usb@vger.kernel.org>, <linux-i2c@vger.kernel.org>,
        <linux-kernel@vger.kernel.org>, <linux-spi@vger.kernel.org>,
        <linux-gpio@vger.kernel.org>, <srinivas.pandruvada@intel.com>,
        <heikki.krogerus@linux.intel.com>,
        <andriy.shevchenko@linux.intel.com>,
        <sakari.ailus@linux.intel.com>, <zhifeng.wang@intel.com>,
        <wentong.wu@intel.com>, <lixu.zhang@intel.com>
Subject: Re: [PATCH v4 1/5] mfd: Add support for Intel LJCA device
Message-ID: <ZAmngB84ty1flD9K@ye-NUC7i7DNHE>
References: <20230309071100.2856899-1-xiang.ye@intel.com>
 <20230309071100.2856899-2-xiang.ye@intel.com>
 <ZAmQOIh/71rY4Pa4@kroah.com>
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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@intel.com/
> 
> > +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?
Could you provide some detail or hints?
> 
> > +
> > +	return count;
> > +}
> > +
> > +static ssize_t cmd_show(struct device *dev, struct device_attribute *attr, char *buf)
> > +{
> > +	return sysfs_emit(buf, "%s\n", "supported cmd: [dfu, debug]");
> 
> sysfs files do not show "help text".
Ok. I can remove this for this has been described in
Documentation/ABI/testing/sysfs-bus-usb-devices-ljca (added in patch 5
of this series).
> 
> thanks,
> 
> greg k-h

--
Thanks
Ye Xiang