[PATCH v3 0/2] CAN: Add support for setting mux

[PATCH v3 0/2] CAN: Add support for setting mux

[Aswath Govindraju]

The following series of patches add support for setting
muxes to route signals from CAN controller to transceiver
by reading the property mux-states from the device tree
node

The following series of patches are dependent on,
- https://lkml.org/lkml/2021/12/2/423

Changes since v2:
- Fixed the bindings removing the description about
  the arguments in mux-states property

Changes since v1:
- Fixed the description for mux-states property in bindings
  file
- appended declaration of variable ret in the end

Aswath Govindraju (2):
  dt-bindings: phy: ti,tcan104x-can: Document mux-states property
  phy: phy-can-transceiver: Add support for setting mux

 .../bindings/phy/ti,tcan104x-can.yaml         |  7 ++++++
 drivers/phy/Kconfig                           |  1 +
 drivers/phy/phy-can-transceiver.c             | 24 ++++++++++++++++++-
 3 files changed, 31 insertions(+), 1 deletion(-)

-- 
2.17.1

[PATCH v3 1/2] dt-bindings: phy: ti,tcan104x-can: Document mux-states property

[Aswath Govindraju]

On some boards, for routing CAN signals from controller to transceivers,
muxes might need to be set. This can be implemented using mux-states
property. Therefore, document the same in the respective bindings.

Signed-off-by: Aswath Govindraju <a-govindraju@ti.com>
---
 Documentation/devicetree/bindings/phy/ti,tcan104x-can.yaml | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/Documentation/devicetree/bindings/phy/ti,tcan104x-can.yaml b/Documentation/devicetree/bindings/phy/ti,tcan104x-can.yaml
index 6107880e5246..02b76f15e717 100644
--- a/Documentation/devicetree/bindings/phy/ti,tcan104x-can.yaml
+++ b/Documentation/devicetree/bindings/phy/ti,tcan104x-can.yaml
@@ -37,6 +37,12 @@ properties:
       max bit rate supported in bps
     minimum: 1
 
+  mux-states:
+    description:
+      mux controller node to route the signals from controller to
+      transceiver.
+    maxItems: 1
+
 required:
   - compatible
   - '#phy-cells'
@@ -53,4 +59,5 @@ examples:
       max-bitrate = <5000000>;
       standby-gpios = <&wakeup_gpio1 16 GPIO_ACTIVE_LOW>;
       enable-gpios = <&main_gpio1 67 GPIO_ACTIVE_HIGH>;
+      mux-states = <&mux0 1>;
     };
-- 
2.17.1

Re: [PATCH v3 1/2] dt-bindings: phy: ti,tcan104x-can: Document mux-states property

[Rob Herring]

On Thu, 16 Dec 2021 09:40:11 +0530, Aswath Govindraju wrote:
> On some boards, for routing CAN signals from controller to transceivers,
> muxes might need to be set. This can be implemented using mux-states
> property. Therefore, document the same in the respective bindings.
> 
> Signed-off-by: Aswath Govindraju <a-govindraju@ti.com>
> ---
>  Documentation/devicetree/bindings/phy/ti,tcan104x-can.yaml | 7 +++++++
>  1 file changed, 7 insertions(+)
> 

Reviewed-by: Rob Herring <robh@kernel.org>

Re: [PATCH v3 1/2] dt-bindings: phy: ti, tcan104x-can: Document mux-states property

[Rob Herring]

On Thu, Dec 16, 2021 at 09:40:11AM +0530, Aswath Govindraju wrote:
> On some boards, for routing CAN signals from controller to transceivers,
> muxes might need to be set. This can be implemented using mux-states
> property. Therefore, document the same in the respective bindings.
> 
> Signed-off-by: Aswath Govindraju <a-govindraju@ti.com>
> ---
>  Documentation/devicetree/bindings/phy/ti,tcan104x-can.yaml | 7 +++++++
>  1 file changed, 7 insertions(+)

As the warning without this is still there and it hasn't been resent, 
I've applied it.

Rob

[PATCH v3 2/2] phy: phy-can-transceiver: Add support for setting mux

[Aswath Govindraju]

On some boards, for routing CAN signals from controller to transceiver,
muxes might need to be set. Therefore, add support for setting the mux by
reading the mux-states property from the device tree node.

Signed-off-by: Aswath Govindraju <a-govindraju@ti.com>
---
 drivers/phy/Kconfig               |  1 +
 drivers/phy/phy-can-transceiver.c | 24 +++++++++++++++++++++++-
 2 files changed, 24 insertions(+), 1 deletion(-)

diff --git a/drivers/phy/Kconfig b/drivers/phy/Kconfig
index 82b63e60c5a2..300b0f2b5f84 100644
--- a/drivers/phy/Kconfig
+++ b/drivers/phy/Kconfig
@@ -64,6 +64,7 @@ config USB_LGM_PHY
 config PHY_CAN_TRANSCEIVER
 	tristate "CAN transceiver PHY"
 	select GENERIC_PHY
+	select MULTIPLEXER
 	help
 	  This option enables support for CAN transceivers as a PHY. This
 	  driver provides function for putting the transceivers in various
diff --git a/drivers/phy/phy-can-transceiver.c b/drivers/phy/phy-can-transceiver.c
index 6f3fe37dee0e..95c6dbb52da7 100644
--- a/drivers/phy/phy-can-transceiver.c
+++ b/drivers/phy/phy-can-transceiver.c
@@ -10,6 +10,7 @@
 #include<linux/module.h>
 #include<linux/gpio.h>
 #include<linux/gpio/consumer.h>
+#include <linux/mux/consumer.h>
 
 struct can_transceiver_data {
 	u32 flags;
@@ -21,13 +22,22 @@ struct can_transceiver_phy {
 	struct phy *generic_phy;
 	struct gpio_desc *standby_gpio;
 	struct gpio_desc *enable_gpio;
+	struct mux_state *mux_state;
 };
 
 /* Power on function */
 static int can_transceiver_phy_power_on(struct phy *phy)
 {
 	struct can_transceiver_phy *can_transceiver_phy = phy_get_drvdata(phy);
-
+	int ret;
+
+	if (can_transceiver_phy->mux_state) {
+		ret = mux_state_select(can_transceiver_phy->mux_state);
+		if (ret) {
+			dev_err(&phy->dev, "Failed to select CAN mux: %d\n", ret);
+			return ret;
+		}
+	}
 	if (can_transceiver_phy->standby_gpio)
 		gpiod_set_value_cansleep(can_transceiver_phy->standby_gpio, 0);
 	if (can_transceiver_phy->enable_gpio)
@@ -45,6 +55,8 @@ static int can_transceiver_phy_power_off(struct phy *phy)
 		gpiod_set_value_cansleep(can_transceiver_phy->standby_gpio, 1);
 	if (can_transceiver_phy->enable_gpio)
 		gpiod_set_value_cansleep(can_transceiver_phy->enable_gpio, 0);
+	if (can_transceiver_phy->mux_state)
+		mux_state_deselect(can_transceiver_phy->mux_state);
 
 	return 0;
 }
@@ -95,6 +107,16 @@ static int can_transceiver_phy_probe(struct platform_device *pdev)
 	match = of_match_node(can_transceiver_phy_ids, pdev->dev.of_node);
 	drvdata = match->data;
 
+	if (of_property_read_bool(dev->of_node, "mux-states")) {
+		struct mux_state *mux_state;
+
+		mux_state = devm_mux_state_get(dev, NULL);
+		if (IS_ERR(mux_state))
+			return dev_err_probe(&pdev->dev, PTR_ERR(mux_state),
+					     "failed to get mux\n");
+		can_transceiver_phy->mux_state = mux_state;
+	}
+
 	phy = devm_phy_create(dev, dev->of_node,
 			      &can_transceiver_phy_ops);
 	if (IS_ERR(phy)) {
-- 
2.17.1

Re: [PATCH v3 0/2] CAN: Add support for setting mux

[Vinod Koul]

On 16-12-21, 09:40, Aswath Govindraju wrote:
> The following series of patches add support for setting
> muxes to route signals from CAN controller to transceiver
> by reading the property mux-states from the device tree
> node

These look okay to me
> 
> The following series of patches are dependent on,
> - https://lkml.org/lkml/2021/12/2/423

Pls post when these are merged..

> 
> Changes since v2:
> - Fixed the bindings removing the description about
>   the arguments in mux-states property
> 
> Changes since v1:
> - Fixed the description for mux-states property in bindings
>   file
> - appended declaration of variable ret in the end
> 
> Aswath Govindraju (2):
>   dt-bindings: phy: ti,tcan104x-can: Document mux-states property
>   phy: phy-can-transceiver: Add support for setting mux
> 
>  .../bindings/phy/ti,tcan104x-can.yaml         |  7 ++++++
>  drivers/phy/Kconfig                           |  1 +
>  drivers/phy/phy-can-transceiver.c             | 24 ++++++++++++++++++-
>  3 files changed, 31 insertions(+), 1 deletion(-)
> 
> -- 
> 2.17.1

-- 
~Vinod