Messages in this thread | | | Date | Thu, 6 Dec 2012 11:55:00 +0100 | From | Peter Ujfalusi <> | Subject | Re: [PATCH] gpio: twl4030: Correct status reporting when the GPIO is used as output |
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On 12/05/2012 11:48 PM, Grant Likely wrote: >> - base = REG_GPIODATAIN1 + d_bnk; >> + direction = gpio_twl4030_read(REG_GPIODATADIR1 + d_bnk); >> + if (direction > 0 && (direction >> d_off) & 0x1) >> + base = REG_SETGPIODATAOUT1 + d_bnk; >> + else >> + base = REG_GPIODATAIN1 + d_bnk; >> + > > This is probably quite expensive considering that reads need to go out > the i2c bus. Things like the output state and the pin direction should > be cached by the driver in its private data structure so that you don't > add an additional i2c round trip.
True. I have sent the v2, which grown a bit since I did not wanted to add more global variable to this driver.
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