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colibri-vf: Disable pull-up configuration in GPIO pin mux

PATCH New Bhuvanchandra DV 2 participants 2 messages Feb 24, 2016 – Mar 2, 2016 Arm (32-bit)

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Bhuvanchandra DV

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PATCH 1/1 colibri-vf: Disable pull-up configuration in GPIO pin mux

During very early boot-ROM execution the pinmux configuration isi in Hi-Z state. If pull-up is enabled on GPIO pad's there will be a short period of toggle from high to low on the IO when GPIO is set low during boot. To avoid this glitch, disable pull-up configuration in GPIO pinmux.

Signed-off-by Bhuvanchandra DV <[email protected]>
---
 arch/arm/include/asm/arch-vf610/iomux-vf610.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
arch/arm/include/asm/arch-vf610/iomux-vf610.h +1 -1
index 0e2bd53..a140be0 100644
@@ -34,7 +34,7 @@
 				PAD_CTL_PUS_22K_UP | PAD_CTL_OBE_IBE_ENABLE)
 
 #define VF610_GPIO_PAD_CTRL	(PAD_CTL_SPEED_MED | PAD_CTL_DSE_50ohm | \
-				PAD_CTL_PUS_47K_UP | PAD_CTL_IBE_ENABLE)
+				PAD_CTL_IBE_ENABLE)
 
 #define VF610_DSPI_PAD_CTRL	(PAD_CTL_OBE_ENABLE | PAD_CTL_DSE_20ohm | \
 				PAD_CTL_PUS_100K_UP | PAD_CTL_SPEED_HIGH)
Signature · 1 line
2.7.1
#1 lore raw

PATCH 1/1 colibri-vf: Disable pull-up configuration in GPIO pin mux

Quoted 18 lines · Bhuvanchandra DV

During very early boot-ROM execution the pinmux configuration isi in Hi-Z state. If pull-up is enabled on GPIO pad's there will be a short period of toggle from high to low on the IO when GPIO is set low during boot. To avoid this glitch, disable pull-up configuration in GPIO pinmux.

Signed-off-by Bhuvanchandra DV <[email protected]>
---
 arch/arm/include/asm/arch-vf610/iomux-vf610.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
arch/arm/include/asm/arch-vf610/iomux-vf610.h +0 -0
index 0e2bd53..a140be0 100644

arch/arm/include/asm/arch-vf610/iomux-vf610.h line 40

Quoted 8 lines
arch/arm/include/asm/arch-vf610/iomux-vf610.h +1 -1
@@ -34,7 +34,7 @@
 				PAD_CTL_PUS_22K_UP | PAD_CTL_OBE_IBE_ENABLE)
 
 #define VF610_GPIO_PAD_CTRL	(PAD_CTL_SPEED_MED | PAD_CTL_DSE_50ohm | \
-				PAD_CTL_PUS_47K_UP | PAD_CTL_IBE_ENABLE)
+				PAD_CTL_IBE_ENABLE)
 
 #define VF610_DSPI_PAD_CTRL	(PAD_CTL_OBE_ENABLE | PAD_CTL_DSE_20ohm | \
 				PAD_CTL_PUS_100K_UP | PAD_CTL_SPEED_HIGH)

As fix, applied to u-boot-imx, thanks !

Best regards,
Stefano Babic

Signature · 5 lines
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