Date: Wed, 28 Jun 2017 20:28:47 +0000 (UTC) From: Ian Lepore <ian@FreeBSD.org> To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: svn commit: r320456 - head/sys/arm/freescale/imx Message-ID: <201706282028.v5SKSl6p095564@repo.freebsd.org>
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Author: ian Date: Wed Jun 28 20:28:47 2017 New Revision: 320456 URL: https://svnweb.freebsd.org/changeset/base/320456 Log: Implement gpio input by reading the pad state register, not the data register. When a pin is set for input the value in the DR will be the same as the PSR. When a pin is set for output the value in the DR is the value output to the pad, and the value in the PSR is the actual electrical level sensed on the pad, and they can be different if the pad is configured for open-drain mode and some other entity on the board is driving the line low. Modified: head/sys/arm/freescale/imx/imx_gpio.c Modified: head/sys/arm/freescale/imx/imx_gpio.c ============================================================================== --- head/sys/arm/freescale/imx/imx_gpio.c Wed Jun 28 19:08:07 2017 (r320455) +++ head/sys/arm/freescale/imx/imx_gpio.c Wed Jun 28 20:28:47 2017 (r320456) @@ -644,7 +644,7 @@ imx51_gpio_pin_get(device_t dev, uint32_t pin, unsigne if (pin >= sc->gpio_npins) return (EINVAL); - *val = (READ4(sc, IMX_GPIO_DR_REG) >> pin) & 1; + *val = (READ4(sc, IMX_GPIO_PSR_REG) >> pin) & 1; return (0); }
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