Re: [PATCH] net: phy: adin1100: Fix nullptr exception for phy interrupts

[Andre Werner <andre.werner@systec-electronic.com>]

On Thu, 18 Jan 2024, Russell King (Oracle) wrote:

> In addition to Andrew's comments:
>
> On Thu, Jan 18, 2024 at 11:43:41AM +0100, Andre Werner wrote:
>> +static int adin_config_intr(struct phy_device *phydev)
>> +{
>> +	int ret, regval;
>> +
>> +	ret = adin_phy_ack_intr(phydev);
>> +
>> +	if (ret)
>> +		return ret;
>> +
>> +	regval = phy_read_mmd(phydev, MDIO_MMD_VEND2, ADIN_PHY_SUBSYS_IRQ_MASK);
>> +	if (regval < 0)
>> +		return regval;
>> +
>> +	if (phydev->interrupts == PHY_INTERRUPT_ENABLED)
>> +		regval |= ADIN_LINK_STAT_CHNG_IRQ_EN;
>> +	else
>> +		regval &= ~ADIN_LINK_STAT_CHNG_IRQ_EN;
>> +
>> +	ret = phy_write_mmd(phydev, MDIO_MMD_VEND2,
>> +			    ADIN_PHY_SUBSYS_IRQ_MASK,
>> +			    regval);
>> +	return ret;
>
> 	u16 irq_mask;
>
> 	if (phydev->interrupts == PHY_INTERRUPT_ENABLED)
> 		irq_mask = ADIN_LINK_STAT_CHNG_IRQ_EN;
> 	else
> 		irq_mask = 0;

Unfortunately, I can not do this, because that phy ask for read-modify-write access to
registers and some bits in this register are already set after reset and
should not being modified.

>
> 	return phy_modify_mmd(phydev, MDIO_MMD_VEND2,
> 			      ADIN_PHY_SUBSYS_IRQ_MASK,
> 			      ADIN_LINK_STAT_CHNG_IRQ_EN, irq_mask);
>
>> +}
>> +
>> +static irqreturn_t adin_phy_handle_interrupt(struct phy_device *phydev)
>> +{
>> +	int irq_status;
>> +
>> +	irq_status = phy_read_mmd(phydev, MDIO_MMD_VEND2, ADIN_PHY_SUBSYS_IRQ_STATUS);
>
> Probably want to wrap this - if you're going to bother wrapping your
> phy_write_mmd() above because it overflows 80 columns, then please do
> so consistently.

Done.

>
> Thanks.
>
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