From mboxrd@z Thu Jan 1 00:00:00 1970 From: Eddie James Date: Tue, 25 Aug 2020 14:47:51 -0500 Subject: [PATCH 3/5] i2c: aspeed: Mask IRQ status to relevant bits In-Reply-To: References: <20200820161152.22751-1-eajames@linux.ibm.com> <20200820161152.22751-4-eajames@linux.ibm.com> Message-ID: <8fc365dd-8a89-9e5c-ed70-093ef2bf7265@linux.ibm.com> List-Id: To: linux-aspeed@lists.ozlabs.org MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit On 8/25/20 1:38 AM, Joel Stanley wrote: > On Thu, 20 Aug 2020 at 16:12, Eddie James 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 >> --- >> 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. Thanks, Eddie