Messages in this thread | | | Date | Thu, 7 Feb 2019 14:37:45 +0100 | From | Andrew Lunn <> | Subject | Re: [PATCH v5] mfd: tqmx86: IO controller with i2c, wachdog and gpio |
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> > + dev_warn(dev, "GPIO interrupts not supported.\n"); > > Do you know why they wouldn't be supported? > > Isn't that the point of the device?
Hi Lee
I don't know the history of this device, but i suspect it has been through a number of revisions. The vendor driver suggests some versions support interrupts from the I2C bus master, but the version i have does not. As a result the i2c bus master has to do polled IO. GPIO interrupts are optional in the GPIO world. So it could be some versions don't support it. But the version i have does.
It seems like if you write to bits of the interrupt configuration register on a revision which don't support interrupts, the write does not stick. So reading it back then lets you know this. The GPIO still works for plain I and O, but don't expect interrupts to work.
Andrew
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