[PATCH v2 0/2] MUX: Add support for mux-states

[PATCH v2 0/2] MUX: Add support for mux-states

[Aswath Govindraju]

The following series of patches add support for reading mux
state from the device tree.

changes since v1:
- Made grammer corrections and added more information
  on the usage for mux-states and mux-controls

Aswath Govindraju (2):
  dt-bindings: mux: Document mux-states property
  mux: Add support for reading mux state from consumer DT node

 .../devicetree/bindings/mux/gpio-mux.yaml     |  11 +-
 .../devicetree/bindings/mux/mux-consumer.yaml |  21 ++
 .../bindings/mux/mux-controller.yaml          |  26 ++-
 drivers/mux/core.c                            | 219 ++++++++++++++++--
 include/linux/mux/consumer.h                  |  19 +-
 5 files changed, 271 insertions(+), 25 deletions(-)

-- 
2.17.1

[PATCH v2 1/2] dt-bindings: mux: Document mux-states property

[Aswath Govindraju]

In some cases, it is required to provide the state to which the mux
controller has to be set to, from the consumer device tree node. Document
the property mux-states that can be used for adding this support.

Signed-off-by: Aswath Govindraju <a-govindraju@ti.com>
---

Note:
- on running dt_binding_check with "DT_CHECKER_FLAGS=-m" the following
  error was seen,

 LINT    Documentation/devicetree/bindings
  CHKDT   Documentation/devicetree/bindings/processed-schema-examples.json
  SCHEMA  Documentation/devicetree/bindings/processed-schema-examples.json
  DTC     Documentation/devicetree/bindings/mux/mux-controller.example.dt.yaml
  CHECK   Documentation/devicetree/bindings/mux/mux-controller.example.dt.yaml
/home/gsaswath/presil/ks3-linux-integrated/linux/Documentation/devicetree/bindings/
mux/mux-controller.example.dt.yaml: can-phy4: 'mux-states' does not match any of 
the regexes: 'pinctrl-[0-9]+'
	From schema: /home/gsaswath/presil/ks3-linux-integrated/linux/
Documentation/devicetree/bindings/phy/ti,tcan104x-can.yaml

"mux-states" is a new property that is being added and the patch adding this
property to TCAN104x can transceiver bindings will be sent as a follow up
of this series.

 .../devicetree/bindings/mux/gpio-mux.yaml     | 11 ++++++--
 .../devicetree/bindings/mux/mux-consumer.yaml | 21 +++++++++++++++
 .../bindings/mux/mux-controller.yaml          | 26 ++++++++++++++++++-
 3 files changed, 55 insertions(+), 3 deletions(-)

diff --git a/Documentation/devicetree/bindings/mux/gpio-mux.yaml b/Documentation/devicetree/bindings/mux/gpio-mux.yaml
index 0a7c8d64981a..ee4de9fbaf4d 100644
--- a/Documentation/devicetree/bindings/mux/gpio-mux.yaml
+++ b/Documentation/devicetree/bindings/mux/gpio-mux.yaml
@@ -26,7 +26,10 @@ properties:
       List of gpios used to control the multiplexer, least significant bit first.
 
   '#mux-control-cells':
-    const: 0
+    enum: [ 0, 1 ]
+
+  '#mux-state-cells':
+    enum: [ 1, 2 ]
 
   idle-state:
     default: -1
@@ -34,7 +37,11 @@ properties:
 required:
   - compatible
   - mux-gpios
-  - "#mux-control-cells"
+anyOf:
+  - required:
+      - "#mux-control-cells"
+  - required:
+      - "#mux-state-cells"
 
 additionalProperties: false
 
diff --git a/Documentation/devicetree/bindings/mux/mux-consumer.yaml b/Documentation/devicetree/bindings/mux/mux-consumer.yaml
index 7af93298ab5c..d3d854967359 100644
--- a/Documentation/devicetree/bindings/mux/mux-consumer.yaml
+++ b/Documentation/devicetree/bindings/mux/mux-consumer.yaml
@@ -25,6 +25,17 @@ description: |
   strings to label each of the mux controllers listed in the "mux-controls"
   property.
 
+  If it is required to provide the state that the mux controller needs to
+  be set to, the property "mux-states" must be used. An optional property
+  "mux-state-names" can be used to provide a list of strings, to label
+  each of the multiplixer states listed in the "mux-states" property.
+
+  Properties "mux-controls" and "mux-states" can be used depending on how
+  the consumers want to control the mux controller. If the consumer needs
+  needs to set multiple states in a mux controller, then property
+  "mux-controls" can be used. If the consumer needs to set the mux
+  controller to a given state then property "mux-states" can be used.
+
   mux-ctrl-specifier typically encodes the chip-relative mux controller number.
   If the mux controller chip only provides a single mux controller, the
   mux-ctrl-specifier can typically be left out.
@@ -35,12 +46,22 @@ properties:
   mux-controls:
     $ref: /schemas/types.yaml#/definitions/phandle-array
 
+  mux-states:
+    $ref: /schemas/types.yaml#/definitions/phandle-array
+
   mux-control-names:
     description:
       Devices that use more than a single mux controller can use the
       "mux-control-names" property to map the name of the requested mux
       controller to an index into the list given by the "mux-controls" property.
 
+  mux-state-names:
+    description:
+      Devices that use more than a single multiplexer state can use the
+      "mux-state-names" property to map the name of the requested mux
+      controller to an index into the list given by the "mux-states"
+      property.
+
 additionalProperties: true
 
 ...
diff --git a/Documentation/devicetree/bindings/mux/mux-controller.yaml b/Documentation/devicetree/bindings/mux/mux-controller.yaml
index 736a84c3b6a5..c855fbad3884 100644
--- a/Documentation/devicetree/bindings/mux/mux-controller.yaml
+++ b/Documentation/devicetree/bindings/mux/mux-controller.yaml
@@ -25,7 +25,9 @@ description: |
   --------------------
 
   Mux controller nodes must specify the number of cells used for the
-  specifier using the '#mux-control-cells' property.
+  specifier using the '#mux-control-cells' or '#mux-state-cells' property.
+  The value of '#mux-state-cells' will always be one greater than the value
+  of '#mux-control-cells'.
 
   Optionally, mux controller nodes can also specify the state the mux should
   have when it is idle. The idle-state property is used for this. If the
@@ -67,6 +69,8 @@ select:
           pattern: '^mux-controller'
     - required:
         - '#mux-control-cells'
+    - required:
+        - '#mux-state-cells'
 
 properties:
   $nodename:
@@ -75,6 +79,9 @@ properties:
   '#mux-control-cells':
     enum: [ 0, 1 ]
 
+  '#mux-state-cells':
+    enum: [ 1, 2 ]
+
   idle-state:
     $ref: /schemas/types.yaml#/definitions/int32
     minimum: -2
@@ -179,4 +186,21 @@ examples:
             };
         };
     };
+
+  - |
+    #include <dt-bindings/gpio/gpio.h>
+
+    mux1: mux-controller {
+        compatible = "gpio-mux";
+        #mux-state-cells = <1>;
+        mux-gpios = <&exp_som 2 GPIO_ACTIVE_HIGH>;
+    };
+
+    transceiver4: can-phy4 {
+        compatible = "ti,tcan1042";
+        #phy-cells = <0>;
+        max-bitrate = <5000000>;
+        standby-gpios = <&exp_som 7 GPIO_ACTIVE_HIGH>;
+        mux-states = <&mux1 1>;
+    };
 ...
-- 
2.17.1

[PATCH v2 2/2] mux: Add support for reading mux state from consumer DT node

[Aswath Govindraju]

In some cases, we might need to provide the state of the mux to be set for
the operation of a given peripheral. Therefore, pass this information using
mux-states property.

Signed-off-by: Aswath Govindraju <a-govindraju@ti.com>
---
 drivers/mux/core.c           | 219 +++++++++++++++++++++++++++++++----
 include/linux/mux/consumer.h |  19 ++-
 2 files changed, 216 insertions(+), 22 deletions(-)

diff --git a/drivers/mux/core.c b/drivers/mux/core.c
index 22f4709768d1..7355c5ad41f7 100644
--- a/drivers/mux/core.c
+++ b/drivers/mux/core.c
@@ -29,6 +29,19 @@
  */
 #define MUX_CACHE_UNKNOWN MUX_IDLE_AS_IS
 
+/**
+ * struct mux_state -	Represents a mux controller specific to a given device
+ * @mux:		Pointer to a mux controller
+ * @state		State of the mux to be set
+ *
+ * This structure is specific to a device that acquires it and has information
+ * specific to the device.
+ */
+struct mux_state {
+	struct mux_control *mux;
+	unsigned int state;
+};
+
 static struct class mux_class = {
 	.name = "mux",
 	.owner = THIS_MODULE,
@@ -370,6 +383,31 @@ int mux_control_select_delay(struct mux_control *mux, unsigned int state,
 }
 EXPORT_SYMBOL_GPL(mux_control_select_delay);
 
+/**
+ * mux_state_select_delay() - Select mux-state
+ * @mstate: The mux-state to select
+ * @delay_us: The time to delay (in microseconds) if the mux control
+ *            changes state on select
+ *
+ * On successfully selecting the mux-state, it will be locked until
+ * there is a call to mux_state_deselect() or mux_control_deselect().
+ * If the mux-control is already selected when mux_state_select() is
+ * called, the caller will be blocked until mux_state_deselect() or
+ * mux_control_deselect() is called (by someone else).
+ *
+ * Therefore, make sure to call mux_state_deselect() when the operation is
+ * complete and the mux-control is free for others to use, but do not call
+ * mux_state_deselect() if mux_state_select() fails.
+ *
+ * Return: 0 when the mux-state has been selected or a negative
+ * errno on error.
+ */
+int mux_state_select_delay(struct mux_state *mstate, unsigned int delay_us)
+{
+	return mux_control_select_delay(mstate->mux, mstate->state, delay_us);
+}
+EXPORT_SYMBOL_GPL(mux_state_select_delay);
+
 /**
  * mux_control_try_select_delay() - Try to select the given multiplexer state.
  * @mux: The mux-control to request a change of state from.
@@ -377,7 +415,7 @@ EXPORT_SYMBOL_GPL(mux_control_select_delay);
  * @delay_us: The time to delay (in microseconds) if the mux state is changed.
  *
  * On successfully selecting the mux-control state, it will be locked until
- * mux_control_deselect() called.
+ * mux_control_deselect() or mux_state_deselect() called.
  *
  * Therefore, make sure to call mux_control_deselect() when the operation is
  * complete and the mux-control is free for others to use, but do not call
@@ -405,6 +443,27 @@ int mux_control_try_select_delay(struct mux_control *mux, unsigned int state,
 }
 EXPORT_SYMBOL_GPL(mux_control_try_select_delay);
 
+/**
+ * mux_state_try_select_delay() - Try to select the mux-state.
+ * @mstate: The mux-state to select
+ * @delay_us: The time to delay (in microseconds) if the mux state is changed.
+ *
+ * On successfully selecting the mux-state, it will be locked until
+ * mux_state_deselect() or mux_control_deselect() is called.
+ *
+ * Therefore, make sure to call mux_state_deselect() when the operation is
+ * complete and the mux-control is free for others to use, but do not call
+ * mux_state_deselect() if mux_state_try_select() fails.
+ *
+ * Return: 0 when the mux-state has been selected or a negative errno on
+ * error. Specifically -EBUSY if the mux-control is contended.
+ */
+int mux_state_try_select_delay(struct mux_state *mstate, unsigned int delay_us)
+{
+	return mux_control_try_select_delay(mstate->mux, mstate->state, delay_us);
+}
+EXPORT_SYMBOL_GPL(mux_state_try_select_delay);
+
 /**
  * mux_control_deselect() - Deselect the previously selected multiplexer state.
  * @mux: The mux-control to deselect.
@@ -431,6 +490,24 @@ int mux_control_deselect(struct mux_control *mux)
 }
 EXPORT_SYMBOL_GPL(mux_control_deselect);
 
+/**
+ * mux_state_deselect() - Deselect the previously selected multiplexer state.
+ * @mstate: The mux-state to deselect.
+ *
+ * It is required that a single call is made to mux_state_deselect() for
+ * each and every successful call made to either of mux_state_select() or
+ * mux_state_try_select().
+ *
+ * Return: 0 on success and a negative errno on error. An error can only
+ * occur if the mux has an idle state. Note that even if an error occurs, the
+ * mux-control is unlocked and is thus free for the next access.
+ */
+int mux_state_deselect(struct mux_state *mstate)
+{
+	return mux_control_deselect(mstate->mux);
+}
+EXPORT_SYMBOL_GPL(mux_state_deselect);
+
 /* Note this function returns a reference to the mux_chip dev. */
 static struct mux_chip *of_find_mux_chip_by_node(struct device_node *np)
 {
@@ -441,14 +518,17 @@ static struct mux_chip *of_find_mux_chip_by_node(struct device_node *np)
 	return dev ? to_mux_chip(dev) : NULL;
 }
 
-/**
- * mux_control_get() - Get the mux-control for a device.
+/*
+ * mux_get() - Get the mux-control for a device.
  * @dev: The device that needs a mux-control.
  * @mux_name: The name identifying the mux-control.
+ * @state: Pointer to where the requested state is returned, or NULL when
+ *         the required multiplexer states are handled by other means.
  *
  * Return: A pointer to the mux-control, or an ERR_PTR with a negative errno.
  */
-struct mux_control *mux_control_get(struct device *dev, const char *mux_name)
+static struct mux_control *mux_get(struct device *dev, const char *mux_name,
+				   unsigned int *state)
 {
 	struct device_node *np = dev->of_node;
 	struct of_phandle_args args;
@@ -458,8 +538,12 @@ struct mux_control *mux_control_get(struct device *dev, const char *mux_name)
 	int ret;
 
 	if (mux_name) {
-		index = of_property_match_string(np, "mux-control-names",
-						 mux_name);
+		if (state)
+			index = of_property_match_string(np, "mux-state-names",
+							 mux_name);
+		else
+			index = of_property_match_string(np, "mux-control-names",
+							 mux_name);
 		if (index < 0) {
 			dev_err(dev, "mux controller '%s' not found\n",
 				mux_name);
@@ -467,12 +551,17 @@ struct mux_control *mux_control_get(struct device *dev, const char *mux_name)
 		}
 	}
 
-	ret = of_parse_phandle_with_args(np,
-					 "mux-controls", "#mux-control-cells",
-					 index, &args);
+	if (state)
+		ret = of_parse_phandle_with_args(np,
+						 "mux-states", "#mux-state-cells",
+						 index, &args);
+	else
+		ret = of_parse_phandle_with_args(np,
+						 "mux-controls", "#mux-control-cells",
+						 index, &args);
 	if (ret) {
-		dev_err(dev, "%pOF: failed to get mux-control %s(%i)\n",
-			np, mux_name ?: "", index);
+		dev_err(dev, "%pOF: failed to get mux-%s %s(%i)\n",
+			np, state ? "state" : "control", mux_name ?: "", index);
 		return ERR_PTR(ret);
 	}
 
@@ -481,17 +570,35 @@ struct mux_control *mux_control_get(struct device *dev, const char *mux_name)
 	if (!mux_chip)
 		return ERR_PTR(-EPROBE_DEFER);
 
-	if (args.args_count > 1 ||
-	    (!args.args_count && (mux_chip->controllers > 1))) {
-		dev_err(dev, "%pOF: wrong #mux-control-cells for %pOF\n",
-			np, args.np);
-		put_device(&mux_chip->dev);
-		return ERR_PTR(-EINVAL);
-	}
-
 	controller = 0;
-	if (args.args_count)
-		controller = args.args[0];
+	if (state) {
+		if (args.args_count > 2 || args.args_count == 0 ||
+		    (args.args_count < 2 && mux_chip->controllers > 1)) {
+			dev_err(dev, "%pOF: wrong #mux-state-cells for %pOF\n",
+				np, args.np);
+			put_device(&mux_chip->dev);
+			return ERR_PTR(-EINVAL);
+		}
+
+		if (args.args_count == 2) {
+			controller = args.args[0];
+			*state = args.args[1];
+		} else {
+			*state = args.args[0];
+		}
+
+	} else {
+		if (args.args_count > 1 ||
+		    (!args.args_count && mux_chip->controllers > 1)) {
+			dev_err(dev, "%pOF: wrong #mux-control-cells for %pOF\n",
+				np, args.np);
+			put_device(&mux_chip->dev);
+			return ERR_PTR(-EINVAL);
+		}
+
+		if (args.args_count)
+			controller = args.args[0];
+	}
 
 	if (controller >= mux_chip->controllers) {
 		dev_err(dev, "%pOF: bad mux controller %u specified in %pOF\n",
@@ -502,6 +609,18 @@ struct mux_control *mux_control_get(struct device *dev, const char *mux_name)
 
 	return &mux_chip->mux[controller];
 }
+
+/**
+ * mux_control_get() - Get the mux-control for a device.
+ * @dev: The device that needs a mux-control.
+ * @mux_name: The name identifying the mux-control.
+ *
+ * Return: A pointer to the mux-control, or an ERR_PTR with a negative errno.
+ */
+struct mux_control *mux_control_get(struct device *dev, const char *mux_name)
+{
+	return mux_get(dev, mux_name, NULL);
+}
 EXPORT_SYMBOL_GPL(mux_control_get);
 
 /**
@@ -523,6 +642,26 @@ static void devm_mux_control_release(struct device *dev, void *res)
 	mux_control_put(mux);
 }
 
+/**
+ * mux_state_put() - Put away the mux-state for good.
+ * @mstate: The mux-state to put away.
+ *
+ * mux_control_put() reverses the effects of mux_control_get().
+ */
+void mux_state_put(struct mux_state *mstate)
+{
+	mux_control_put(mstate->mux);
+	kfree(mstate);
+}
+EXPORT_SYMBOL_GPL(mux_state_put);
+
+static void devm_mux_state_release(struct device *dev, void *res)
+{
+	struct mux_state *mstate = *(struct mux_state **)res;
+
+	mux_state_put(mstate);
+}
+
 /**
  * devm_mux_control_get() - Get the mux-control for a device, with resource
  *			    management.
@@ -553,6 +692,44 @@ struct mux_control *devm_mux_control_get(struct device *dev,
 }
 EXPORT_SYMBOL_GPL(devm_mux_control_get);
 
+/**
+ * devm_mux_state_get() - Get the mux-state for a device, with resource
+ *			  management.
+ * @dev: The device that needs a mux-control.
+ * @mux_name: The name identifying the mux-control.
+ *
+ * Return: Pointer to the mux-state, or an ERR_PTR with a negative errno.
+ */
+struct mux_state *devm_mux_state_get(struct device *dev,
+				     const char *mux_name)
+{
+	struct mux_state **ptr, *mstate;
+	struct mux_control *mux_ctrl;
+	int state;
+
+	mstate = devm_kzalloc(dev, sizeof(struct mux_state), GFP_KERNEL);
+	if (!mstate)
+		return ERR_PTR(-ENOMEM);
+
+	ptr = devres_alloc(devm_mux_state_release, sizeof(*ptr), GFP_KERNEL);
+	if (!ptr)
+		return ERR_PTR(-ENOMEM);
+
+	mux_ctrl = mux_get(dev, mux_name, &state);
+	if (IS_ERR(mux_ctrl)) {
+		devres_free(ptr);
+		return (struct mux_state *)mux_ctrl;
+	}
+
+	mstate->mux = mux_ctrl;
+	mstate->state = state;
+	*ptr = mstate;
+	devres_add(dev, ptr);
+
+	return mstate;
+}
+EXPORT_SYMBOL_GPL(devm_mux_state_get);
+
 /*
  * Using subsys_initcall instead of module_init here to try to ensure - for
  * the non-modular case - that the subsystem is initialized when mux consumers
diff --git a/include/linux/mux/consumer.h b/include/linux/mux/consumer.h
index 7a09b040ac39..bf5abf062c21 100644
--- a/include/linux/mux/consumer.h
+++ b/include/linux/mux/consumer.h
@@ -14,33 +14,50 @@
 
 struct device;
 struct mux_control;
+struct mux_state;
 
 unsigned int mux_control_states(struct mux_control *mux);
 int __must_check mux_control_select_delay(struct mux_control *mux,
 					  unsigned int state,
 					  unsigned int delay_us);
+int __must_check mux_state_select_delay(struct mux_state *mstate,
+					unsigned int delay_us);
 int __must_check mux_control_try_select_delay(struct mux_control *mux,
 					      unsigned int state,
 					      unsigned int delay_us);
-
+int __must_check mux_state_try_select_delay(struct mux_state *mstate,
+					    unsigned int delay_us);
 static inline int __must_check mux_control_select(struct mux_control *mux,
 						  unsigned int state)
 {
 	return mux_control_select_delay(mux, state, 0);
 }
 
+static inline int __must_check mux_state_select(struct mux_state *mstate)
+{
+	return mux_state_select_delay(mstate, 0);
+}
 static inline int __must_check mux_control_try_select(struct mux_control *mux,
 						      unsigned int state)
 {
 	return mux_control_try_select_delay(mux, state, 0);
 }
 
+static inline int __must_check mux_state_try_select(struct mux_state *mstate)
+{
+	return mux_state_try_select_delay(mstate, 0);
+}
+
 int mux_control_deselect(struct mux_control *mux);
+int mux_state_deselect(struct mux_state *mstate);
 
 struct mux_control *mux_control_get(struct device *dev, const char *mux_name);
 void mux_control_put(struct mux_control *mux);
+void mux_state_put(struct mux_state *mstate);
 
 struct mux_control *devm_mux_control_get(struct device *dev,
 					 const char *mux_name);
+struct mux_state *devm_mux_state_get(struct device *dev,
+				     const char *mux_name);
 
 #endif /* _LINUX_MUX_CONSUMER_H */
-- 
2.17.1

Re: [PATCH v2 1/2] dt-bindings: mux: Document mux-states property

[Rob Herring]

On Thu, 02 Dec 2021 18:10:52 +0530, Aswath Govindraju wrote:
> In some cases, it is required to provide the state to which the mux
> controller has to be set to, from the consumer device tree node. Document
> the property mux-states that can be used for adding this support.
> 
> Signed-off-by: Aswath Govindraju <a-govindraju@ti.com>
> ---
> 
> Note:
> - on running dt_binding_check with "DT_CHECKER_FLAGS=-m" the following
>   error was seen,
> 
>  LINT    Documentation/devicetree/bindings
>   CHKDT   Documentation/devicetree/bindings/processed-schema-examples.json
>   SCHEMA  Documentation/devicetree/bindings/processed-schema-examples.json
>   DTC     Documentation/devicetree/bindings/mux/mux-controller.example.dt.yaml
>   CHECK   Documentation/devicetree/bindings/mux/mux-controller.example.dt.yaml
> /home/gsaswath/presil/ks3-linux-integrated/linux/Documentation/devicetree/bindings/
> mux/mux-controller.example.dt.yaml: can-phy4: 'mux-states' does not match any of
> the regexes: 'pinctrl-[0-9]+'
> 	From schema: /home/gsaswath/presil/ks3-linux-integrated/linux/
> Documentation/devicetree/bindings/phy/ti,tcan104x-can.yaml
> 
> "mux-states" is a new property that is being added and the patch adding this
> property to TCAN104x can transceiver bindings will be sent as a follow up
> of this series.
> 
>  .../devicetree/bindings/mux/gpio-mux.yaml     | 11 ++++++--
>  .../devicetree/bindings/mux/mux-consumer.yaml | 21 +++++++++++++++
>  .../bindings/mux/mux-controller.yaml          | 26 ++++++++++++++++++-
>  3 files changed, 55 insertions(+), 3 deletions(-)
> 

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

Re: [PATCH v2 0/2] MUX: Add support for mux-states

[Peter Rosin]

Hi Aswath!

On 2021-12-02 13:40, Aswath Govindraju wrote:
> The following series of patches add support for reading mux
> state from the device tree.
> 
> changes since v1:
> - Made grammer corrections and added more information
>   on the usage for mux-states and mux-controls
> 
> Aswath Govindraju (2):
>   dt-bindings: mux: Document mux-states property
>   mux: Add support for reading mux state from consumer DT node
> 
>  .../devicetree/bindings/mux/gpio-mux.yaml     |  11 +-
>  .../devicetree/bindings/mux/mux-consumer.yaml |  21 ++
>  .../bindings/mux/mux-controller.yaml          |  26 ++-
>  drivers/mux/core.c                            | 219 ++++++++++++++++--
>  include/linux/mux/consumer.h                  |  19 +-
>  5 files changed, 271 insertions(+), 25 deletions(-)
> 

I finally found some time to have a last look at this (fingers crossed) and
pushed it out for testing in linux-next.

I did end up squashing in these trivial changes in patch 2/2, I hope that's
fine with you. Just holler if not...

Cheers,
Peter

diff --git a/Documentation/driver-api/driver-model/devres.rst b/Documentation/driver-api/driver-model/devres.rst
index 148e19381b79..5018403fe82f 100644
--- a/Documentation/driver-api/driver-model/devres.rst
+++ b/Documentation/driver-api/driver-model/devres.rst
@@ -368,6 +368,7 @@ MUX
   devm_mux_chip_alloc()
   devm_mux_chip_register()
   devm_mux_control_get()
+  devm_mux_state_get()
 
 NET
   devm_alloc_etherdev()
diff --git a/drivers/mux/core.c b/drivers/mux/core.c
index 7355c5ad41f7..bf448069ca85 100644
--- a/drivers/mux/core.c
+++ b/drivers/mux/core.c
@@ -30,12 +30,13 @@
 #define MUX_CACHE_UNKNOWN MUX_IDLE_AS_IS
 
 /**
- * struct mux_state -	Represents a mux controller specific to a given device
- * @mux:		Pointer to a mux controller
- * @state		State of the mux to be set
+ * struct mux_state -	Represents a mux controller state specific to a given
+ *			consumer.
+ * @mux:		Pointer to a mux controller.
+ * @state		State of the mux to be selected.
  *
- * This structure is specific to a device that acquires it and has information
- * specific to the device.
+ * This structure is specific to the consumer that acquires it and has
+ * information specific to that consumer.
  */
 struct mux_state {
 	struct mux_control *mux;
@@ -354,7 +355,8 @@ static void mux_control_delay(struct mux_control *mux, unsigned int delay_us)
  * On successfully selecting the mux-control state, it will be locked until
  * there is a call to mux_control_deselect(). If the mux-control is already
  * selected when mux_control_select() is called, the caller will be blocked
- * until mux_control_deselect() is called (by someone else).
+ * until mux_control_deselect() or mux_state_deselect() is called (by someone
+ * else).
  *
  * Therefore, make sure to call mux_control_deselect() when the operation is
  * complete and the mux-control is free for others to use, but do not call
@@ -384,16 +386,15 @@ int mux_control_select_delay(struct mux_control *mux, unsigned int state,
 EXPORT_SYMBOL_GPL(mux_control_select_delay);
 
 /**
- * mux_state_select_delay() - Select mux-state
- * @mstate: The mux-state to select
- * @delay_us: The time to delay (in microseconds) if the mux control
- *            changes state on select
+ * mux_state_select_delay() - Select the given multiplexer state.
+ * @mstate: The mux-state to select.
+ * @delay_us: The time to delay (in microseconds) if the mux state is changed.
  *
- * On successfully selecting the mux-state, it will be locked until
- * there is a call to mux_state_deselect() or mux_control_deselect().
- * If the mux-control is already selected when mux_state_select() is
- * called, the caller will be blocked until mux_state_deselect() or
- * mux_control_deselect() is called (by someone else).
+ * On successfully selecting the mux-state, its mux-control will be locked
+ * until there is a call to mux_state_deselect(). If the mux-control is already
+ * selected when mux_state_select() is called, the caller will be blocked
+ * until mux_state_deselect() or mux_control_deselect() is called (by someone
+ * else).
  *
  * Therefore, make sure to call mux_state_deselect() when the operation is
  * complete and the mux-control is free for others to use, but do not call
@@ -415,7 +416,7 @@ EXPORT_SYMBOL_GPL(mux_state_select_delay);
  * @delay_us: The time to delay (in microseconds) if the mux state is changed.
  *
  * On successfully selecting the mux-control state, it will be locked until
- * mux_control_deselect() or mux_state_deselect() called.
+ * mux_control_deselect() called.
  *
  * Therefore, make sure to call mux_control_deselect() when the operation is
  * complete and the mux-control is free for others to use, but do not call
@@ -444,12 +445,12 @@ int mux_control_try_select_delay(struct mux_control *mux, unsigned int state,
 EXPORT_SYMBOL_GPL(mux_control_try_select_delay);
 
 /**
- * mux_state_try_select_delay() - Try to select the mux-state.
- * @mstate: The mux-state to select
+ * mux_state_try_select_delay() - Try to select the given multiplexer state.
+ * @mstate: The mux-state to select.
  * @delay_us: The time to delay (in microseconds) if the mux state is changed.
  *
- * On successfully selecting the mux-state, it will be locked until
- * mux_state_deselect() or mux_control_deselect() is called.
+ * On successfully selecting the mux-state, its mux-control will be locked
+ * until mux_state_deselect() is called.
  *
  * Therefore, make sure to call mux_state_deselect() when the operation is
  * complete and the mux-control is free for others to use, but do not call
@@ -642,26 +643,6 @@ static void devm_mux_control_release(struct device *dev, void *res)
 	mux_control_put(mux);
 }
 
-/**
- * mux_state_put() - Put away the mux-state for good.
- * @mstate: The mux-state to put away.
- *
- * mux_control_put() reverses the effects of mux_control_get().
- */
-void mux_state_put(struct mux_state *mstate)
-{
-	mux_control_put(mstate->mux);
-	kfree(mstate);
-}
-EXPORT_SYMBOL_GPL(mux_state_put);
-
-static void devm_mux_state_release(struct device *dev, void *res)
-{
-	struct mux_state *mstate = *(struct mux_state **)res;
-
-	mux_state_put(mstate);
-}
-
 /**
  * devm_mux_control_get() - Get the mux-control for a device, with resource
  *			    management.
@@ -692,6 +673,26 @@ struct mux_control *devm_mux_control_get(struct device *dev,
 }
 EXPORT_SYMBOL_GPL(devm_mux_control_get);
 
+/**
+ * mux_state_put() - Put away the mux-state for good.
+ * @mstate: The mux-state to put away.
+ *
+ * mux_control_put() reverses the effects of mux_control_get().
+ */
+void mux_state_put(struct mux_state *mstate)
+{
+	mux_control_put(mstate->mux);
+	kfree(mstate);
+}
+EXPORT_SYMBOL_GPL(mux_state_put);
+
+static void devm_mux_state_release(struct device *dev, void *res)
+{
+	struct mux_state *mstate = *(struct mux_state **)res;
+
+	mux_state_put(mstate);
+}
+
 /**
  * devm_mux_state_get() - Get the mux-state for a device, with resource
  *			  management.
diff --git a/include/linux/mux/consumer.h b/include/linux/mux/consumer.h
index bf5abf062c21..babf2a744056 100644
--- a/include/linux/mux/consumer.h
+++ b/include/linux/mux/consumer.h
@@ -27,6 +27,7 @@ int __must_check mux_control_try_select_delay(struct mux_control *mux,
 					      unsigned int delay_us);
 int __must_check mux_state_try_select_delay(struct mux_state *mstate,
 					    unsigned int delay_us);
+
 static inline int __must_check mux_control_select(struct mux_control *mux,
 						  unsigned int state)
 {
@@ -37,6 +38,7 @@ static inline int __must_check mux_state_select(struct mux_state *mstate)
 {
 	return mux_state_select_delay(mstate, 0);
 }
+
 static inline int __must_check mux_control_try_select(struct mux_control *mux,
 						      unsigned int state)
 {

Re: [PATCH v2 0/2] MUX: Add support for mux-states

[Peter Rosin]

Hi again.

On 2021-12-17 06:57, Peter Rosin wrote:
> Hi Aswath!
> 
> On 2021-12-02 13:40, Aswath Govindraju wrote:
>> The following series of patches add support for reading mux
>> state from the device tree.
>>
>> changes since v1:
>> - Made grammer corrections and added more information
>>   on the usage for mux-states and mux-controls
>>
>> Aswath Govindraju (2):
>>   dt-bindings: mux: Document mux-states property
>>   mux: Add support for reading mux state from consumer DT node
>>
>>  .../devicetree/bindings/mux/gpio-mux.yaml     |  11 +-
>>  .../devicetree/bindings/mux/mux-consumer.yaml |  21 ++
>>  .../bindings/mux/mux-controller.yaml          |  26 ++-
>>  drivers/mux/core.c                            | 219 ++++++++++++++++--
>>  include/linux/mux/consumer.h                  |  19 +-
>>  5 files changed, 271 insertions(+), 25 deletions(-)
>>
> 
> I finally found some time to have a last look at this (fingers crossed) and
> pushed it out for testing in linux-next.
> 
> I did end up squashing in these trivial changes in patch 2/2, I hope that's
> fine with you. Just holler if not...
> 
> Cheers,
> Peter
> 
> diff --git a/Documentation/driver-api/driver-model/devres.rst b/Documentation/driver-api/driver-model/devres.rst
> index 148e19381b79..5018403fe82f 100644
> --- a/Documentation/driver-api/driver-model/devres.rst
> +++ b/Documentation/driver-api/driver-model/devres.rst
> @@ -368,6 +368,7 @@ MUX
>    devm_mux_chip_alloc()
>    devm_mux_chip_register()
>    devm_mux_control_get()
> +  devm_mux_state_get()
>  
>  NET
>    devm_alloc_etherdev()
> diff --git a/drivers/mux/core.c b/drivers/mux/core.c
> index 7355c5ad41f7..bf448069ca85 100644
> --- a/drivers/mux/core.c
> +++ b/drivers/mux/core.c
> @@ -30,12 +30,13 @@
>  #define MUX_CACHE_UNKNOWN MUX_IDLE_AS_IS
>  
>  /**
> - * struct mux_state -	Represents a mux controller specific to a given device
> - * @mux:		Pointer to a mux controller
> - * @state		State of the mux to be set
> + * struct mux_state -	Represents a mux controller state specific to a given
> + *			consumer.
> + * @mux:		Pointer to a mux controller.
> + * @state		State of the mux to be selected.
>   *
> - * This structure is specific to a device that acquires it and has information
> - * specific to the device.
> + * This structure is specific to the consumer that acquires it and has
> + * information specific to that consumer.
>   */
>  struct mux_state {
>  	struct mux_control *mux;
> @@ -354,7 +355,8 @@ static void mux_control_delay(struct mux_control *mux, unsigned int delay_us)
>   * On successfully selecting the mux-control state, it will be locked until
>   * there is a call to mux_control_deselect(). If the mux-control is already
>   * selected when mux_control_select() is called, the caller will be blocked
> - * until mux_control_deselect() is called (by someone else).
> + * until mux_control_deselect() or mux_state_deselect() is called (by someone
> + * else).
>   *
>   * Therefore, make sure to call mux_control_deselect() when the operation is
>   * complete and the mux-control is free for others to use, but do not call
> @@ -384,16 +386,15 @@ int mux_control_select_delay(struct mux_control *mux, unsigned int state,
>  EXPORT_SYMBOL_GPL(mux_control_select_delay);
>  
>  /**
> - * mux_state_select_delay() - Select mux-state
> - * @mstate: The mux-state to select
> - * @delay_us: The time to delay (in microseconds) if the mux control
> - *            changes state on select
> + * mux_state_select_delay() - Select the given multiplexer state.
> + * @mstate: The mux-state to select.
> + * @delay_us: The time to delay (in microseconds) if the mux state is changed.
>   *
> - * On successfully selecting the mux-state, it will be locked until
> - * there is a call to mux_state_deselect() or mux_control_deselect().
> - * If the mux-control is already selected when mux_state_select() is
> - * called, the caller will be blocked until mux_state_deselect() or
> - * mux_control_deselect() is called (by someone else).
> + * On successfully selecting the mux-state, its mux-control will be locked
> + * until there is a call to mux_state_deselect(). If the mux-control is already
> + * selected when mux_state_select() is called, the caller will be blocked
> + * until mux_state_deselect() or mux_control_deselect() is called (by someone
> + * else).
>   *
>   * Therefore, make sure to call mux_state_deselect() when the operation is
>   * complete and the mux-control is free for others to use, but do not call
> @@ -415,7 +416,7 @@ EXPORT_SYMBOL_GPL(mux_state_select_delay);
>   * @delay_us: The time to delay (in microseconds) if the mux state is changed.
>   *
>   * On successfully selecting the mux-control state, it will be locked until
> - * mux_control_deselect() or mux_state_deselect() called.
> + * mux_control_deselect() called.
>   *
>   * Therefore, make sure to call mux_control_deselect() when the operation is
>   * complete and the mux-control is free for others to use, but do not call
> @@ -444,12 +445,12 @@ int mux_control_try_select_delay(struct mux_control *mux, unsigned int state,
>  EXPORT_SYMBOL_GPL(mux_control_try_select_delay);
>  
>  /**
> - * mux_state_try_select_delay() - Try to select the mux-state.
> - * @mstate: The mux-state to select
> + * mux_state_try_select_delay() - Try to select the given multiplexer state.
> + * @mstate: The mux-state to select.
>   * @delay_us: The time to delay (in microseconds) if the mux state is changed.
>   *
> - * On successfully selecting the mux-state, it will be locked until
> - * mux_state_deselect() or mux_control_deselect() is called.
> + * On successfully selecting the mux-state, its mux-control will be locked
> + * until mux_state_deselect() is called.
>   *
>   * Therefore, make sure to call mux_state_deselect() when the operation is
>   * complete and the mux-control is free for others to use, but do not call
> @@ -642,26 +643,6 @@ static void devm_mux_control_release(struct device *dev, void *res)
>  	mux_control_put(mux);
>  }
>  
> -/**
> - * mux_state_put() - Put away the mux-state for good.
> - * @mstate: The mux-state to put away.
> - *
> - * mux_control_put() reverses the effects of mux_control_get().
> - */
> -void mux_state_put(struct mux_state *mstate)
> -{
> -	mux_control_put(mstate->mux);
> -	kfree(mstate);
> -}
> -EXPORT_SYMBOL_GPL(mux_state_put);
> -
> -static void devm_mux_state_release(struct device *dev, void *res)
> -{
> -	struct mux_state *mstate = *(struct mux_state **)res;
> -
> -	mux_state_put(mstate);
> -}
> -
>  /**
>   * devm_mux_control_get() - Get the mux-control for a device, with resource
>   *			    management.
> @@ -692,6 +673,26 @@ struct mux_control *devm_mux_control_get(struct device *dev,
>  }
>  EXPORT_SYMBOL_GPL(devm_mux_control_get);
>  
> +/**
> + * mux_state_put() - Put away the mux-state for good.
> + * @mstate: The mux-state to put away.
> + *
> + * mux_control_put() reverses the effects of mux_control_get().

And, a couple of minutes later, I squashed in this on top:

- * mux_control_put() reverses the effects of mux_control_get().
+ * mux_state_put() reverses the effects of mux_state_get().

Cheers,
Peter

> + */
> +void mux_state_put(struct mux_state *mstate)
> +{
> +	mux_control_put(mstate->mux);
> +	kfree(mstate);
> +}
> +EXPORT_SYMBOL_GPL(mux_state_put);
> +
> +static void devm_mux_state_release(struct device *dev, void *res)
> +{
> +	struct mux_state *mstate = *(struct mux_state **)res;
> +
> +	mux_state_put(mstate);
> +}
> +
>  /**
>   * devm_mux_state_get() - Get the mux-state for a device, with resource
>   *			  management.
> diff --git a/include/linux/mux/consumer.h b/include/linux/mux/consumer.h
> index bf5abf062c21..babf2a744056 100644
> --- a/include/linux/mux/consumer.h
> +++ b/include/linux/mux/consumer.h
> @@ -27,6 +27,7 @@ int __must_check mux_control_try_select_delay(struct mux_control *mux,
>  					      unsigned int delay_us);
>  int __must_check mux_state_try_select_delay(struct mux_state *mstate,
>  					    unsigned int delay_us);
> +
>  static inline int __must_check mux_control_select(struct mux_control *mux,
>  						  unsigned int state)
>  {
> @@ -37,6 +38,7 @@ static inline int __must_check mux_state_select(struct mux_state *mstate)
>  {
>  	return mux_state_select_delay(mstate, 0);
>  }
> +
>  static inline int __must_check mux_control_try_select(struct mux_control *mux,
>  						      unsigned int state)
>  {
> 

Re: [PATCH v2 0/2] MUX: Add support for mux-states

[Peter Rosin]

Hi Aswath!

See below.

On 2021-12-17 07:26, Peter Rosin wrote:
> Hi again.
> 
> On 2021-12-17 06:57, Peter Rosin wrote:
>> Hi Aswath!
>>
>> On 2021-12-02 13:40, Aswath Govindraju wrote:
>>> The following series of patches add support for reading mux
>>> state from the device tree.
>>>
>>> changes since v1:
>>> - Made grammer corrections and added more information
>>>   on the usage for mux-states and mux-controls
>>>
>>> Aswath Govindraju (2):
>>>   dt-bindings: mux: Document mux-states property
>>>   mux: Add support for reading mux state from consumer DT node
>>>
>>>  .../devicetree/bindings/mux/gpio-mux.yaml     |  11 +-
>>>  .../devicetree/bindings/mux/mux-consumer.yaml |  21 ++
>>>  .../bindings/mux/mux-controller.yaml          |  26 ++-
>>>  drivers/mux/core.c                            | 219 ++++++++++++++++--
>>>  include/linux/mux/consumer.h                  |  19 +-
>>>  5 files changed, 271 insertions(+), 25 deletions(-)
>>>
>>
>> I finally found some time to have a last look at this (fingers crossed) and
>> pushed it out for testing in linux-next.
>>
>> I did end up squashing in these trivial changes in patch 2/2, I hope that's
>> fine with you. Just holler if not...
>>
>> Cheers,
>> Peter
>>
>> diff --git a/Documentation/driver-api/driver-model/devres.rst b/Documentation/driver-api/driver-model/devres.rst
>> index 148e19381b79..5018403fe82f 100644
>> --- a/Documentation/driver-api/driver-model/devres.rst
>> +++ b/Documentation/driver-api/driver-model/devres.rst
>> @@ -368,6 +368,7 @@ MUX
>>    devm_mux_chip_alloc()
>>    devm_mux_chip_register()
>>    devm_mux_control_get()
>> +  devm_mux_state_get()
>>  
>>  NET
>>    devm_alloc_etherdev()
>> diff --git a/drivers/mux/core.c b/drivers/mux/core.c
>> index 7355c5ad41f7..bf448069ca85 100644
>> --- a/drivers/mux/core.c
>> +++ b/drivers/mux/core.c
>> @@ -30,12 +30,13 @@
>>  #define MUX_CACHE_UNKNOWN MUX_IDLE_AS_IS
>>  
>>  /**
>> - * struct mux_state -	Represents a mux controller specific to a given device
>> - * @mux:		Pointer to a mux controller
>> - * @state		State of the mux to be set
>> + * struct mux_state -	Represents a mux controller state specific to a given
>> + *			consumer.
>> + * @mux:		Pointer to a mux controller.
>> + * @state		State of the mux to be selected.
>>   *
>> - * This structure is specific to a device that acquires it and has information
>> - * specific to the device.
>> + * This structure is specific to the consumer that acquires it and has
>> + * information specific to that consumer.
>>   */
>>  struct mux_state {
>>  	struct mux_control *mux;
>> @@ -354,7 +355,8 @@ static void mux_control_delay(struct mux_control *mux, unsigned int delay_us)
>>   * On successfully selecting the mux-control state, it will be locked until
>>   * there is a call to mux_control_deselect(). If the mux-control is already
>>   * selected when mux_control_select() is called, the caller will be blocked
>> - * until mux_control_deselect() is called (by someone else).
>> + * until mux_control_deselect() or mux_state_deselect() is called (by someone
>> + * else).
>>   *
>>   * Therefore, make sure to call mux_control_deselect() when the operation is
>>   * complete and the mux-control is free for others to use, but do not call
>> @@ -384,16 +386,15 @@ int mux_control_select_delay(struct mux_control *mux, unsigned int state,
>>  EXPORT_SYMBOL_GPL(mux_control_select_delay);
>>  
>>  /**
>> - * mux_state_select_delay() - Select mux-state
>> - * @mstate: The mux-state to select
>> - * @delay_us: The time to delay (in microseconds) if the mux control
>> - *            changes state on select
>> + * mux_state_select_delay() - Select the given multiplexer state.
>> + * @mstate: The mux-state to select.
>> + * @delay_us: The time to delay (in microseconds) if the mux state is changed.
>>   *
>> - * On successfully selecting the mux-state, it will be locked until
>> - * there is a call to mux_state_deselect() or mux_control_deselect().
>> - * If the mux-control is already selected when mux_state_select() is
>> - * called, the caller will be blocked until mux_state_deselect() or
>> - * mux_control_deselect() is called (by someone else).
>> + * On successfully selecting the mux-state, its mux-control will be locked
>> + * until there is a call to mux_state_deselect(). If the mux-control is already
>> + * selected when mux_state_select() is called, the caller will be blocked
>> + * until mux_state_deselect() or mux_control_deselect() is called (by someone
>> + * else).
>>   *
>>   * Therefore, make sure to call mux_state_deselect() when the operation is
>>   * complete and the mux-control is free for others to use, but do not call
>> @@ -415,7 +416,7 @@ EXPORT_SYMBOL_GPL(mux_state_select_delay);
>>   * @delay_us: The time to delay (in microseconds) if the mux state is changed.
>>   *
>>   * On successfully selecting the mux-control state, it will be locked until
>> - * mux_control_deselect() or mux_state_deselect() called.
>> + * mux_control_deselect() called.
>>   *
>>   * Therefore, make sure to call mux_control_deselect() when the operation is
>>   * complete and the mux-control is free for others to use, but do not call
>> @@ -444,12 +445,12 @@ int mux_control_try_select_delay(struct mux_control *mux, unsigned int state,
>>  EXPORT_SYMBOL_GPL(mux_control_try_select_delay);
>>  
>>  /**
>> - * mux_state_try_select_delay() - Try to select the mux-state.
>> - * @mstate: The mux-state to select
>> + * mux_state_try_select_delay() - Try to select the given multiplexer state.
>> + * @mstate: The mux-state to select.
>>   * @delay_us: The time to delay (in microseconds) if the mux state is changed.
>>   *
>> - * On successfully selecting the mux-state, it will be locked until
>> - * mux_state_deselect() or mux_control_deselect() is called.
>> + * On successfully selecting the mux-state, its mux-control will be locked
>> + * until mux_state_deselect() is called.
>>   *
>>   * Therefore, make sure to call mux_state_deselect() when the operation is
>>   * complete and the mux-control is free for others to use, but do not call
>> @@ -642,26 +643,6 @@ static void devm_mux_control_release(struct device *dev, void *res)
>>  	mux_control_put(mux);
>>  }
>>  
>> -/**
>> - * mux_state_put() - Put away the mux-state for good.
>> - * @mstate: The mux-state to put away.
>> - *
>> - * mux_control_put() reverses the effects of mux_control_get().
>> - */
>> -void mux_state_put(struct mux_state *mstate)
>> -{
>> -	mux_control_put(mstate->mux);
>> -	kfree(mstate);
>> -}
>> -EXPORT_SYMBOL_GPL(mux_state_put);
>> -
>> -static void devm_mux_state_release(struct device *dev, void *res)
>> -{
>> -	struct mux_state *mstate = *(struct mux_state **)res;
>> -
>> -	mux_state_put(mstate);
>> -}
>> -
>>  /**
>>   * devm_mux_control_get() - Get the mux-control for a device, with resource
>>   *			    management.
>> @@ -692,6 +673,26 @@ struct mux_control *devm_mux_control_get(struct device *dev,
>>  }
>>  EXPORT_SYMBOL_GPL(devm_mux_control_get);
>>  
>> +/**
>> + * mux_state_put() - Put away the mux-state for good.
>> + * @mstate: The mux-state to put away.
>> + *
>> + * mux_control_put() reverses the effects of mux_control_get().
> 
> And, a couple of minutes later, I squashed in this on top:
> 
> - * mux_control_put() reverses the effects of mux_control_get().
> + * mux_state_put() reverses the effects of mux_state_get().
> 

And now I notice that there is no mux_state_get. There should be one,
in my opinion, at least if there is an exported mux_state_put.

So, Aswath, can you please test the patch that's coming as a reply
to this message on top of what is currently on its way into linux-next?

I.e. wait for the next linux-next to be released, or
https://gitlab.com/peda-linux/mux.git#for-next

Or, optionally, just grab the mux-state-get branch:

https://gitlab.com/peda-linux/mux.git#mux-state-get

Cheers,
Peter

> 
>> + */
>> +void mux_state_put(struct mux_state *mstate)
>> +{
>> +	mux_control_put(mstate->mux);
>> +	kfree(mstate);
>> +}
>> +EXPORT_SYMBOL_GPL(mux_state_put);
>> +
>> +static void devm_mux_state_release(struct device *dev, void *res)
>> +{
>> +	struct mux_state *mstate = *(struct mux_state **)res;
>> +
>> +	mux_state_put(mstate);
>> +}
>> +
>>  /**
>>   * devm_mux_state_get() - Get the mux-state for a device, with resource
>>   *			  management.
>> diff --git a/include/linux/mux/consumer.h b/include/linux/mux/consumer.h
>> index bf5abf062c21..babf2a744056 100644
>> --- a/include/linux/mux/consumer.h
>> +++ b/include/linux/mux/consumer.h
>> @@ -27,6 +27,7 @@ int __must_check mux_control_try_select_delay(struct mux_control *mux,
>>  					      unsigned int delay_us);
>>  int __must_check mux_state_try_select_delay(struct mux_state *mstate,
>>  					    unsigned int delay_us);
>> +
>>  static inline int __must_check mux_control_select(struct mux_control *mux,
>>  						  unsigned int state)
>>  {
>> @@ -37,6 +38,7 @@ static inline int __must_check mux_state_select(struct mux_state *mstate)
>>  {
>>  	return mux_state_select_delay(mstate, 0);
>>  }
>> +
>>  static inline int __must_check mux_control_try_select(struct mux_control *mux,
>>  						      unsigned int state)
>>  {
>>

[PATCH] mux: add missing mux_state_get

[Peter Rosin]

And implement devm_mux_state_get in terms of the new function.

Signed-off-by: Peter Rosin <peda@axentia.se>
---
 drivers/mux/core.c           | 41 ++++++++++++++++++++++++++----------
 include/linux/mux/consumer.h |  1 +
 2 files changed, 31 insertions(+), 11 deletions(-)

diff --git a/drivers/mux/core.c b/drivers/mux/core.c
index 7d38e7c0c02e..90073ce01539 100644
--- a/drivers/mux/core.c
+++ b/drivers/mux/core.c
@@ -673,6 +673,33 @@ struct mux_control *devm_mux_control_get(struct device *dev,
 }
 EXPORT_SYMBOL_GPL(devm_mux_control_get);
 
+/**
+ * mux_state_get() - Get the mux-state for a device.
+ * @dev: The device that needs a mux-state.
+ * @mux_name: The name identifying the mux-state.
+ *
+ * Return: A pointer to the mux-state, or an ERR_PTR with a negative errno.
+ */
+struct mux_state *mux_state_get(struct device *dev, const char *mux_name)
+{
+	struct mux_state *mstate;
+
+	mstate = kzalloc(sizeof(*mstate), GFP_KERNEL);
+	if (!mstate)
+		return ERR_PTR(-ENOMEM);
+
+	mstate->mux = mux_get(dev, mux_name, &mstate->state);
+	if (IS_ERR(mstate->mux)) {
+		int err = PTR_ERR(mstate->mux);
+
+		kfree(mstate);
+		return ERR_PTR(err);
+	}
+
+	return mstate;
+}
+EXPORT_SYMBOL_GPL(mux_state_get);
+
 /**
  * mux_state_put() - Put away the mux-state for good.
  * @mstate: The mux-state to put away.
@@ -705,25 +732,17 @@ struct mux_state *devm_mux_state_get(struct device *dev,
 				     const char *mux_name)
 {
 	struct mux_state **ptr, *mstate;
-	struct mux_control *mux_ctrl;
-	int state;
-
-	mstate = devm_kzalloc(dev, sizeof(struct mux_state), GFP_KERNEL);
-	if (!mstate)
-		return ERR_PTR(-ENOMEM);
 
 	ptr = devres_alloc(devm_mux_state_release, sizeof(*ptr), GFP_KERNEL);
 	if (!ptr)
 		return ERR_PTR(-ENOMEM);
 
-	mux_ctrl = mux_get(dev, mux_name, &state);
-	if (IS_ERR(mux_ctrl)) {
+	mstate = mux_state_get(dev, mux_name);
+	if (IS_ERR(mstate)) {
 		devres_free(ptr);
-		return (struct mux_state *)mux_ctrl;
+		return mstate;
 	}
 
-	mstate->mux = mux_ctrl;
-	mstate->state = state;
 	*ptr = mstate;
 	devres_add(dev, ptr);
 
diff --git a/include/linux/mux/consumer.h b/include/linux/mux/consumer.h
index babf2a744056..944678604549 100644
--- a/include/linux/mux/consumer.h
+++ b/include/linux/mux/consumer.h
@@ -54,6 +54,7 @@ int mux_control_deselect(struct mux_control *mux);
 int mux_state_deselect(struct mux_state *mstate);
 
 struct mux_control *mux_control_get(struct device *dev, const char *mux_name);
+struct mux_state *mux_state_get(struct device *dev, const char *mux_name);
 void mux_control_put(struct mux_control *mux);
 void mux_state_put(struct mux_state *mstate);
 
-- 
2.20.1

Re: [PATCH] mux: add missing mux_state_get

[Aswath Govindraju]

On 19/12/21 12:07 am, Peter Rosin wrote:
> And implement devm_mux_state_get in terms of the new function.
> 
> Signed-off-by: Peter Rosin <peda@axentia.se>

Tested-by: Aswath Govindraju <a-govindraju@ti.com>

Thanks,
Aswath

> ---
>  drivers/mux/core.c           | 41 ++++++++++++++++++++++++++----------
>  include/linux/mux/consumer.h |  1 +
>  2 files changed, 31 insertions(+), 11 deletions(-)
> 
> diff --git a/drivers/mux/core.c b/drivers/mux/core.c
> index 7d38e7c0c02e..90073ce01539 100644
> --- a/drivers/mux/core.c
> +++ b/drivers/mux/core.c
> @@ -673,6 +673,33 @@ struct mux_control *devm_mux_control_get(struct device *dev,
>  }
>  EXPORT_SYMBOL_GPL(devm_mux_control_get);
>  
> +/**
> + * mux_state_get() - Get the mux-state for a device.
> + * @dev: The device that needs a mux-state.
> + * @mux_name: The name identifying the mux-state.
> + *
> + * Return: A pointer to the mux-state, or an ERR_PTR with a negative errno.
> + */
> +struct mux_state *mux_state_get(struct device *dev, const char *mux_name)
> +{
> +	struct mux_state *mstate;
> +
> +	mstate = kzalloc(sizeof(*mstate), GFP_KERNEL);
> +	if (!mstate)
> +		return ERR_PTR(-ENOMEM);
> +
> +	mstate->mux = mux_get(dev, mux_name, &mstate->state);
> +	if (IS_ERR(mstate->mux)) {
> +		int err = PTR_ERR(mstate->mux);
> +
> +		kfree(mstate);
> +		return ERR_PTR(err);
> +	}
> +
> +	return mstate;
> +}
> +EXPORT_SYMBOL_GPL(mux_state_get);
> +
>  /**
>   * mux_state_put() - Put away the mux-state for good.
>   * @mstate: The mux-state to put away.
> @@ -705,25 +732,17 @@ struct mux_state *devm_mux_state_get(struct device *dev,
>  				     const char *mux_name)
>  {
>  	struct mux_state **ptr, *mstate;
> -	struct mux_control *mux_ctrl;
> -	int state;
> -
> -	mstate = devm_kzalloc(dev, sizeof(struct mux_state), GFP_KERNEL);
> -	if (!mstate)
> -		return ERR_PTR(-ENOMEM);
>  
>  	ptr = devres_alloc(devm_mux_state_release, sizeof(*ptr), GFP_KERNEL);
>  	if (!ptr)
>  		return ERR_PTR(-ENOMEM);
>  
> -	mux_ctrl = mux_get(dev, mux_name, &state);
> -	if (IS_ERR(mux_ctrl)) {
> +	mstate = mux_state_get(dev, mux_name);
> +	if (IS_ERR(mstate)) {
>  		devres_free(ptr);
> -		return (struct mux_state *)mux_ctrl;
> +		return mstate;
>  	}
>  
> -	mstate->mux = mux_ctrl;
> -	mstate->state = state;
>  	*ptr = mstate;
>  	devres_add(dev, ptr);
>  
> diff --git a/include/linux/mux/consumer.h b/include/linux/mux/consumer.h
> index babf2a744056..944678604549 100644
> --- a/include/linux/mux/consumer.h
> +++ b/include/linux/mux/consumer.h
> @@ -54,6 +54,7 @@ int mux_control_deselect(struct mux_control *mux);
>  int mux_state_deselect(struct mux_state *mstate);
>  
>  struct mux_control *mux_control_get(struct device *dev, const char *mux_name);
> +struct mux_state *mux_state_get(struct device *dev, const char *mux_name);
>  void mux_control_put(struct mux_control *mux);
>  void mux_state_put(struct mux_state *mstate);
>  
> 

Re: [PATCH] mux: add missing mux_state_get

[Peter Rosin]

On 2021-12-20 07:57, Aswath Govindraju wrote:
> 
> On 19/12/21 12:07 am, Peter Rosin wrote:
>> And implement devm_mux_state_get in terms of the new function.
>>
>> Signed-off-by: Peter Rosin <peda@axentia.se>
> 
> Tested-by: Aswath Govindraju <a-govindraju@ti.com>

Thanks!

I added the commit to the for-next branch. I will pass these mux
patches on to Greg when they have been in linux-next for a couple
of days for the bots to chew on. I can't be sure this will make
5.17-rc1 though, when we're already at 5.16-rc6 and the hollidays
are coming up.

We'll see.

Cheers,
Peter