[PATCH v4 06/10] phy: qcom: Add M31 based eUSB2 PHY driver

Vinod Koul vkoul at kernel.org
Wed May 14 01:33:44 PDT 2025


On 16-04-25, 15:45, Wesley Cheng wrote:
> Hi Vinod,
> 
> On 4/10/2025 4:53 AM, Vinod Koul wrote:
> > On 09-04-25, 10:48, Melody Olvera wrote:
> > 
> >> +static int m31eusb2_phy_write_readback(void __iomem *base, u32 offset,
> >> +					const u32 mask, u32 val)
> >> +{
> >> +	u32 write_val;
> >> +	u32 tmp;
> >> +
> >> +	tmp = readl_relaxed(base + offset);
> >> +	tmp &= ~mask;
> >> +	write_val = tmp | val;
> >> +
> >> +	writel_relaxed(write_val, base + offset);
> >> +
> >> +	tmp = readl_relaxed(base + offset);
> > 
> > Why are you using _relaxed version here?
> > 
> 
> No particular reason.  I think someone pointed this out previously, and I
> was open to use the non-relaxed variants, but I assume using the relaxed vs
> non-relaxed apis comes down to preference in this case.

Nope you cant! There _needs_ to be a specific reasons!
When you are doing read, modify, write, it is very important to know the
right version to use...

-- 
~Vinod



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