Re: [PATCH 1/1] USB: PHY: JZ4770: Fix uninitialized value written to HW register

From: Felipe Balbi
Date: Thu Aug 27 2020 - 09:31:42 EST



Hi,

Paul Cercueil <paul@xxxxxxxxxxxxxxx> writes:
>>> @@ -172,7 +172,8 @@ static int ingenic_usb_phy_init(struct usb_phy
>>> *phy)
>>> return err;
>>> }
>>>
>>> - priv->soc_info->usb_phy_init(phy);
>>> + reg = priv->soc_info->usb_phy_init(phy);
>>> + writel(reg, priv->base + REG_USBPCR_OFFSET);
>>
>> not fixing any bug.
>>
>> Looking at the code, the bug follows after this line. It would suffice
>> to read REG_USBPCR_OFFSET in order to initialize reg. This bug fix
>> could
>> have been a one liner.
>
> There's no need to re-read a register when you have the value readily
> available. It just needs to be returned from the usb_phy_init
> callbacks. But yes, it's not a one-liner.

there's a difference between making a bug fix and reworking the behavior
of the driver ;-)

>>> @@ -195,19 +196,15 @@ static void ingenic_usb_phy_remove(void *phy)
>>> usb_remove_phy(phy);
>>> }
>>>
>>> -static void jz4770_usb_phy_init(struct usb_phy *phy)
>>> +static u32 jz4770_usb_phy_init(struct usb_phy *phy)
>>
>> not a bug fix
>>
>>> {
>>> - struct jz4770_phy *priv = phy_to_jz4770_phy(phy);
>>> - u32 reg;
>>> -
>>> - reg = USBPCR_AVLD_REG | USBPCR_COMMONONN | USBPCR_IDPULLUP_ALWAYS
>>> |
>>> + return USBPCR_AVLD_REG | USBPCR_COMMONONN |
>>> USBPCR_IDPULLUP_ALWAYS |
>>> USBPCR_COMPDISTUNE_DFT | USBPCR_OTGTUNE_DFT |
>>> USBPCR_SQRXTUNE_DFT |
>>> USBPCR_TXFSLSTUNE_DFT | USBPCR_TXRISETUNE_DFT |
>>> USBPCR_TXVREFTUNE_DFT |
>>> USBPCR_POR;
>>> - writel(reg, priv->base + REG_USBPCR_OFFSET);
>>
>> not a bug fix
>>
>>> }
>>>
>>> -static void jz4780_usb_phy_init(struct usb_phy *phy)
>>> +static u32 jz4780_usb_phy_init(struct usb_phy *phy)
>>
>> not a bug fix
>>
>>> @@ -216,11 +213,10 @@ static void jz4780_usb_phy_init(struct
>>> usb_phy *phy)
>>> USBPCR1_WORD_IF_16BIT;
>>> writel(reg, priv->base + REG_USBPCR1_OFFSET);
>>>
>>> - reg = USBPCR_TXPREEMPHTUNE | USBPCR_COMMONONN | USBPCR_POR;
>>> - writel(reg, priv->base + REG_USBPCR_OFFSET);
>>> + return USBPCR_TXPREEMPHTUNE | USBPCR_COMMONONN | USBPCR_POR;
>>
>> not a bug fix
>>
>>> }
>>>
>>> -static void x1000_usb_phy_init(struct usb_phy *phy)
>>> +static u32 x1000_usb_phy_init(struct usb_phy *phy)
>>
>> not a bug fix
>>
>>> {
>>> struct jz4770_phy *priv = phy_to_jz4770_phy(phy);
>>> u32 reg;
>>> @@ -228,13 +224,12 @@ static void x1000_usb_phy_init(struct usb_phy
>>> *phy)
>>> reg = readl(priv->base + REG_USBPCR1_OFFSET) |
>>> USBPCR1_WORD_IF_16BIT;
>>> writel(reg, priv->base + REG_USBPCR1_OFFSET);
>>>
>>> - reg = USBPCR_SQRXTUNE_DCR_20PCT | USBPCR_TXPREEMPHTUNE |
>>> + return USBPCR_SQRXTUNE_DCR_20PCT | USBPCR_TXPREEMPHTUNE |
>>> USBPCR_TXHSXVTUNE_DCR_15MV | USBPCR_TXVREFTUNE_INC_25PPT |
>>> USBPCR_COMMONONN | USBPCR_POR;
>>> - writel(reg, priv->base + REG_USBPCR_OFFSET);
>>
>> not a bug fix
>>
>>> }
>>>
>>> -static void x1830_usb_phy_init(struct usb_phy *phy)
>>> +static u32 x1830_usb_phy_init(struct usb_phy *phy)
>>
>> not a bug fix
>>
>>> {
>>> struct jz4770_phy *priv = phy_to_jz4770_phy(phy);
>>> u32 reg;
>>> @@ -246,9 +241,8 @@ static void x1830_usb_phy_init(struct usb_phy
>>> *phy)
>>> USBPCR1_DMPD | USBPCR1_DPPD;
>>> writel(reg, priv->base + REG_USBPCR1_OFFSET);
>>>
>>> - reg = USBPCR_IDPULLUP_OTG | USBPCR_VBUSVLDEXT
>>> | USBPCR_TXPREEMPHTUNE |
>>> + return USBPCR_IDPULLUP_OTG | USBPCR_VBUSVLDEXT |
>>> USBPCR_TXPREEMPHTUNE |
>>> USBPCR_COMMONONN | USBPCR_POR;
>>> - writel(reg, priv->base + REG_USBPCR_OFFSET);
>>
>> not a bug fix
>
> Well, if you don't like my bug fix, next time wait for my Reviewed-by.

why so angry? Take a break every once in a while. Besides, someone else
already sent the oneliner before you ;-)

In any case, why should I wait for your Reviewed-by? Get maintainer
doesn't list you as the maintainer for it. Do you want to update
MAINTAINERS by any chance?

--
balbi

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