On Tue, Aug 25, 2020 at 02:47:51PM -0500, Eddie James wrote: > > On 8/25/20 1:38 AM, Joel Stanley wrote: > > On Thu, 20 Aug 2020 at 16:12, Eddie James <eajames@xxxxxxxxxxxxx> wrote: > > > Mask the IRQ status to only the bits that the driver checks. This > > > prevents excessive driver warnings when operating in slave mode > > > when additional bits are set that the driver doesn't handle. > > > > > > Signed-off-by: Eddie James <eajames@xxxxxxxxxxxxx> > > > --- > > > drivers/i2c/busses/i2c-aspeed.c | 1 + > > > 1 file changed, 1 insertion(+) > > > > > > diff --git a/drivers/i2c/busses/i2c-aspeed.c b/drivers/i2c/busses/i2c-aspeed.c > > > index 31268074c422..abf40f2af8b4 100644 > > > --- a/drivers/i2c/busses/i2c-aspeed.c > > > +++ b/drivers/i2c/busses/i2c-aspeed.c > > > @@ -604,6 +604,7 @@ static irqreturn_t aspeed_i2c_bus_irq(int irq, void *dev_id) > > > writel(irq_received & ~ASPEED_I2CD_INTR_RX_DONE, > > > bus->base + ASPEED_I2C_INTR_STS_REG); > > > readl(bus->base + ASPEED_I2C_INTR_STS_REG); > > > + irq_received &= 0xf000ffff; > > > irq_remaining = irq_received; > > This would defeat the check for irq_remaining. I don't think we want to do this. > > > > Can you explain why these bits are being set in slave mode? > > > No, I don't have any documentation for the bits that are masked off here, so > I don't know why they would get set. > > The check for irq_remaining is still useful for detecting that the driver > state machine might be out of sync with what the master is doing. I have a similar patch in my local tree, and the reason being: AST2600 I2C Controller may set I2CD10[25:24] to report Current Slave Parking Status (defined in new register I2CS24) even though the new register mode is off. The 2 bits can be ignored in legacy mode, and Ryan from ASPEED could confirm it. Cheers, Tao
