Re: [PATCH] identify firmware version

[Jiri Slaby <jirislaby@gmail.com>]

On 09/06/2010 09:48 PM, Dmitry Torokhov wrote:
>> @@ -848,10 +871,43 @@ static int ntrig_probe(struct hid_device *hdev, const struct hid_device_id *id)
>>  	if (report)
>>  		usbhid_submit_report(hdev, report, USB_DIR_OUT);
>>  
>> +	data = kmalloc(8, GFP_KERNEL);
>> +	if (!data) {
>> +		ret = -ENOMEM;
>> +		goto err_free;
>> +	}
>> +
>> +	ret = usb_control_msg(usb_dev, usb_rcvctrlpipe(usb_dev, 0),
>> +			      USB_REQ_CLEAR_FEATURE,
>> +			      USB_TYPE_CLASS | USB_RECIP_INTERFACE |
>> +			      USB_DIR_IN,
>> +			      0x30c, 1, data, 8,
>> +			      USB_CTRL_SET_TIMEOUT);
>> +
>> +	if (ret == 8) {
>> +		buf = kmalloc(20, GFP_KERNEL);
>> +		if (!buf) {
>> +			ret = -ENOMEM;
>> +			goto err_free_data;
>> +		}
> 
> Why do you allocate this from heap? Surely we can spare 20 bytes on
> stack (you aren't doing DMA into it).

Hi, yeah, I think so too.

> I'd also split all this code into ntrig_report_version() to simplifu
> error handling here.
> 
>> +
>> +		ret = ntrig_version_string(&data[2], buf);
>> +
>> +		dev_info(&hdev->dev,
>> +			 "Firmware version: %s (%02x%02x %02x%02x)\n",
>> +			 buf, data[2], data[3], data[4], data[5]);
>> +
>> +		kfree(buff);

In any case, this doesn't compile...

>> +	}

regards,
-- 
js