Re: [PATCH v2 03/15] net: rnpgbe: Add basic mbx ops support

[Yibo Dong]

On Tue, Jul 22, 2025 at 12:35:42PM +0100, Simon Horman wrote:
> On Mon, Jul 21, 2025 at 07:32:26PM +0800, Dong Yibo wrote:
> > Initialize basic mbx function.
> > 
> > Signed-off-by: Dong Yibo <dong100@xxxxxxxxx>
> 
> ...
> 
> > diff --git a/drivers/net/ethernet/mucse/rnpgbe/rnpgbe_mbx.c b/drivers/net/ethernet/mucse/rnpgbe/rnpgbe_mbx.c
> 
> ...
> 
> > +/**
> > + * mucse_obtain_mbx_lock_pf - obtain mailbox lock
> > + * @hw: pointer to the HW structure
> > + * @mbx_id: Id of vf/fw to obtain
> > + *
> > + * This function maybe used in an irq handler.
> > + *
> > + * @return: 0 if we obtained the mailbox lock
> > + **/
> > +static int mucse_obtain_mbx_lock_pf(struct mucse_hw *hw, enum MBX_ID mbx_id)
> > +{
> > +	struct mucse_mbx_info *mbx = &hw->mbx;
> > +	int try_cnt = 5000, ret;
> > +	u32 reg;
> > +
> > +	reg = (mbx_id == MBX_FW) ? PF2FW_MBOX_CTRL(mbx) :
> > +				   PF2VF_MBOX_CTRL(mbx, mbx_id);
> > +	while (try_cnt-- > 0) {
> > +		/* Take ownership of the buffer */
> > +		mbx_wr32(hw, reg, MBOX_PF_HOLD);
> > +		/* force write back before check */
> > +		wmb();
> > +		if (mbx_rd32(hw, reg) & MBOX_PF_HOLD)
> > +			return 0;
> > +		udelay(100);
> > +	}
> > +	return ret;
> 
> ret is declared, and returned here.
> But it is never initialised.
> 
> Perhaps it is appropriate to return an error value here,
> and update the kernel doc for this function accordingly.
> 
> Flagged by W=1 builds with Clang 20.1.8, and Smatch.
> 
> > +}
> 
> ...
> 

Got it, I will fix this.
Maybe my clang (10.0.0) is too old, I will update it and 
try W=1 again.
Thanks for your feedback.