Hi,
On 7/3/2020 11:29 AM, Greg KH wrote:
> On Thu, Jul 02, 2020 at 03:46:06PM +0100, Lee Jones wrote:
>> Commit ec1f9d9f01384 ("usb: dwc2: gadget: parity fix in isochronous mode") moved
>> these checks to dwc2_hsotg_change_ep_iso_parity() back in 2015. The assigned
>> value hasn't been read back since. Let's remove the unnecessary H/W read.
>>
>> Fixes the following W=1 warning:
>>
>> drivers/usb/dwc2/gadget.c: In function ‘dwc2_hsotg_epint’:
>> drivers/usb/dwc2/gadget.c:2981:6: warning: variable ‘ctrl’ set but not used [-Wunused-but-set-variable]
>> 2981 | u32 ctrl;
>> | ^~~~
>>
>> Cc: Minas Harutyunyan <hminas@xxxxxxxxxxxx>
>> Cc: Ben Dooks <ben@xxxxxxxxxxxx>
>> Signed-off-by: Lee Jones <lee.jones@xxxxxxxxxx>
>> ---
>> drivers/usb/dwc2/gadget.c | 2 --
>> 1 file changed, 2 deletions(-)
>>
>> diff --git a/drivers/usb/dwc2/gadget.c b/drivers/usb/dwc2/gadget.c
>> index 116e6175c7a48..fa07e3fcb8841 100644
>> --- a/drivers/usb/dwc2/gadget.c
>> +++ b/drivers/usb/dwc2/gadget.c
>> @@ -2975,10 +2975,8 @@ static void dwc2_hsotg_epint(struct dwc2_hsotg *hsotg, unsigned int idx,
>> u32 epctl_reg = dir_in ? DIEPCTL(idx) : DOEPCTL(idx);
>> u32 epsiz_reg = dir_in ? DIEPTSIZ(idx) : DOEPTSIZ(idx);
>> u32 ints;
>> - u32 ctrl;
>>
>> ints = dwc2_gadget_read_ep_interrupts(hsotg, idx, dir_in);
>> - ctrl = dwc2_readl(hsotg, epctl_reg);
>
> As you know, lots of hardware requires reads to happen to do things, so
> are you sure it is safe to remove this read call?
>
Greg, yes, it's Ok to remove this unnecessary read which remained from
previous implementations.
Lee, please add "Fixes:" tag and resubmit v2.
Thanks,
Minas
> thanks,
>
> greg k-h
>
