The macro allows easy setting in per-pin, as for example:
,---- | imx_iomux_v3_setup_pad(MX6_PAD_NANDF_D1__GPIO_2_1 | MUX_MODE_SION); `----
The IOMUX_CONFIG_SION allows for reading PAD value from PSR register.
The following quote from the datasheet:
,---- | ... | 28.4.2.2 GPIO Write Mode | The programming sequence for driving output signals should be as follows: | 1. Configure IOMUX to select GPIO mode (Via IOMUXC), also enable SION if need | to read loopback pad value through PSR | 2. Configure GPIO direction register to output (GPIO_GDIR[GDIR] set to 1b). | 3. Write value to data register (GPIO_DR). | ... `----
This fixes the gpio_get_value to properly work when a GPIO is set for output and has no conflicts.
Thanks for Benoît Thébaudeau benoit.thebaudeau@advansee.com, Fabio Estevam fabio.estevam@freescale.com and Eric Bénard eric@eukrea.com for helping to properly trace this down.
Signed-off-by: Otavio Salvador otavio@ossystems.com.br --- arch/arm/include/asm/imx-common/iomux-v3.h | 1 + 1 file changed, 1 insertion(+)
diff --git a/arch/arm/include/asm/imx-common/iomux-v3.h b/arch/arm/include/asm/imx-common/iomux-v3.h index dc2b3ef..b7bdaa5 100644 --- a/arch/arm/include/asm/imx-common/iomux-v3.h +++ b/arch/arm/include/asm/imx-common/iomux-v3.h @@ -57,6 +57,7 @@ typedef u64 iomux_v3_cfg_t; MUX_SEL_INPUT_OFS_SHIFT)
#define MUX_MODE_SHIFT 36 +#define MUX_MODE_SION ((iomux_v3_cfg_t)IOMUX_CONFIG_SION << MUX_MODE_SHIFT) #define MUX_MODE_MASK ((iomux_v3_cfg_t)0x1f << MUX_MODE_SHIFT) #define MUX_PAD_CTRL_SHIFT 41 #define MUX_PAD_CTRL_MASK ((iomux_v3_cfg_t)0x3ffff << MUX_PAD_CTRL_SHIFT)