ARM: dts: dra7x-evm: avoid possible contention while muxing on CAN lines

DCAN1 RX and TX lines are internally pulled high according to [1].
While muxing between DCAN mode and SAFE mode we make sure
that the same pull direction is set to minimize opposite
pull contention during the switching window.

[1] in DRA7 data manual, Ball characteristics table 4-2, DSIS colum shows
the state driven to the peripheral input while in the deselcted mode.
DSIS - De-Selected Input State.

Signed-off-by: Roger Quadros <rogerq@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>

diff --git a/arch/arm/boot/dts/dra7-evm.dts b/arch/arm/boot/dts/dra7-evm.dts
index ddef593..7563d7c 100644 (file)
--- a/arch/arm/boot/dts/dra7-evm.dts
+++ b/arch/arm/boot/dts/dra7-evm.dts
@@ -263,15 +263,15 @@
 
        dcan1_pins_default: dcan1_pins_default {
                pinctrl-single,pins = <
-                       0x3d0   (PIN_OUTPUT | MUX_MODE0) /* dcan1_tx */
-                       0x418   (PULL_DIS | MUX_MODE1) /* wakeup0.dcan1_rx */
+                       0x3d0   (PIN_OUTPUT_PULLUP | MUX_MODE0) /* dcan1_tx */
+                       0x418   (PULL_UP | MUX_MODE1) /* wakeup0.dcan1_rx */
                >;
        };
 
        dcan1_pins_sleep: dcan1_pins_sleep {
                pinctrl-single,pins = <
-                       0x3d0   (MUX_MODE15)    /* dcan1_tx.off */
-                       0x418   (MUX_MODE15)    /* wakeup0.off */
+                       0x3d0   (MUX_MODE15 | PULL_UP)  /* dcan1_tx.off */
+                       0x418   (MUX_MODE15 | PULL_UP)  /* wakeup0.off */
                >;
        };
 };

diff --git a/arch/arm/boot/dts/dra72-evm.dts b/arch/arm/boot/dts/dra72-evm.dts
index 42ee09a..40ed539 100644 (file)
--- a/arch/arm/boot/dts/dra72-evm.dts
+++ b/arch/arm/boot/dts/dra72-evm.dts
@@ -119,15 +119,15 @@
 
        dcan1_pins_default: dcan1_pins_default {
                pinctrl-single,pins = <
-                       0x3d0   (PIN_OUTPUT | MUX_MODE0) /* dcan1_tx */
-                       0x418   (PULL_DIS | MUX_MODE1) /* wakeup0.dcan1_rx */
+                       0x3d0   (PIN_OUTPUT_PULLUP | MUX_MODE0) /* dcan1_tx */
+                       0x418   (PULL_UP | MUX_MODE1)   /* wakeup0.dcan1_rx */
                >;
        };
 
        dcan1_pins_sleep: dcan1_pins_sleep {
                pinctrl-single,pins = <
-                       0x3d0   (MUX_MODE15)    /* dcan1_tx.off */
-                       0x418   (MUX_MODE15)    /* wakeup0.off */
+                       0x3d0   (MUX_MODE15 | PULL_UP)  /* dcan1_tx.off */
+                       0x418   (MUX_MODE15 | PULL_UP)  /* wakeup0.off */
                >;
        };