1 files changed, 177 insertions, 103 deletions

diff --git a/drivers/pinctrl/pinmux.c b/drivers/pinctrl/pinmux.c
index addba55334d9..3a8dd184ba3d 100644
--- a/drivers/pinctrl/pinmux.c
+++ b/drivers/pinctrl/pinmux.c
@@ -14,6 +14,7 @@
 
 #include <linux/array_size.h>
 #include <linux/ctype.h>
+#include <linux/cleanup.h>
 #include <linux/debugfs.h>
 #include <linux/device.h>
 #include <linux/err.h>
@@ -88,12 +89,20 @@ bool pinmux_can_be_used_for_gpio(struct pinctrl_dev *pctldev, unsigned int pin)
 {
 	struct pin_desc *desc = pin_desc_get(pctldev, pin);
 	const struct pinmux_ops *ops = pctldev->desc->pmxops;
+	const struct pinctrl_setting_mux *mux_setting;
+	bool func_is_gpio = false;
 
 	/* Can't inspect pin, assume it can be used */
 	if (!desc || !ops)
 		return true;
 
-	if (ops->strict && desc->mux_usecount)
+	mux_setting = desc->mux_setting;
+
+	guard(mutex)(&desc->mux_lock);
+	if (mux_setting && ops->function_is_gpio)
+		func_is_gpio = ops->function_is_gpio(pctldev, mux_setting->func);
+
+	if (ops->strict && desc->mux_usecount && !func_is_gpio)
 		return false;
 
 	return !(ops->strict && !!desc->gpio_owner);
@@ -114,7 +123,9 @@ static int pin_request(struct pinctrl_dev *pctldev,
 {
 	struct pin_desc *desc;
 	const struct pinmux_ops *ops = pctldev->desc->pmxops;
+	const struct pinctrl_setting_mux *mux_setting;
 	int status = -EINVAL;
+	bool gpio_ok = false;
 
 	desc = pin_desc_get(pctldev, pin);
 	if (desc == NULL) {
@@ -124,32 +135,44 @@ static int pin_request(struct pinctrl_dev *pctldev,
 		goto out;
 	}
 
+	mux_setting = desc->mux_setting;
+
 	dev_dbg(pctldev->dev, "request pin %d (%s) for %s\n",
 		pin, desc->name, owner);
 
-	if ((!gpio_range || ops->strict) &&
-	    desc->mux_usecount && strcmp(desc->mux_owner, owner)) {
-		dev_err(pctldev->dev,
-			"pin %s already requested by %s; cannot claim for %s\n",
-			desc->name, desc->mux_owner, owner);
-		goto out;
-	}
+	scoped_guard(mutex, &desc->mux_lock) {
+		if (mux_setting) {
+			if (ops->function_is_gpio)
+				gpio_ok = ops->function_is_gpio(pctldev,
+								mux_setting->func);
+		} else {
+			gpio_ok = true;
+		}
 
-	if ((gpio_range || ops->strict) && desc->gpio_owner) {
-		dev_err(pctldev->dev,
-			"pin %s already requested by %s; cannot claim for %s\n",
-			desc->name, desc->gpio_owner, owner);
-		goto out;
-	}
+		if ((!gpio_range || ops->strict) && !gpio_ok &&
+		    desc->mux_usecount && strcmp(desc->mux_owner, owner)) {
+			dev_err(pctldev->dev,
+				"pin %s already requested by %s; cannot claim for %s\n",
+				desc->name, desc->mux_owner, owner);
+			goto out;
+		}
 
-	if (gpio_range) {
-		desc->gpio_owner = owner;
-	} else {
-		desc->mux_usecount++;
-		if (desc->mux_usecount > 1)
-			return 0;
+		if ((gpio_range || ops->strict) && !gpio_ok && desc->gpio_owner) {
+			dev_err(pctldev->dev,
+				"pin %s already requested by %s; cannot claim for %s\n",
+				desc->name, desc->gpio_owner, owner);
+			goto out;
+		}
 
-		desc->mux_owner = owner;
+		if (gpio_range) {
+			desc->gpio_owner = owner;
+		} else {
+			desc->mux_usecount++;
+			if (desc->mux_usecount > 1)
+				return 0;
+
+			desc->mux_owner = owner;
+		}
 	}
 
 	/* Let each pin increase references to this module */
@@ -178,12 +201,14 @@ static int pin_request(struct pinctrl_dev *pctldev,
 
 out_free_pin:
 	if (status) {
-		if (gpio_range) {
-			desc->gpio_owner = NULL;
-		} else {
-			desc->mux_usecount--;
-			if (!desc->mux_usecount)
-				desc->mux_owner = NULL;
+		scoped_guard(mutex, &desc->mux_lock) {
+			if (gpio_range) {
+				desc->gpio_owner = NULL;
+			} else {
+				desc->mux_usecount--;
+				if (!desc->mux_usecount)
+					desc->mux_owner = NULL;
+			}
 		}
 	}
 out:
@@ -219,15 +244,26 @@ static const char *pin_free(struct pinctrl_dev *pctldev, int pin,
 		return NULL;
 	}
 
-	if (!gpio_range) {
-		/*
-		 * A pin should not be freed more times than allocated.
-		 */
-		if (WARN_ON(!desc->mux_usecount))
-			return NULL;
-		desc->mux_usecount--;
-		if (desc->mux_usecount)
-			return NULL;
+	scoped_guard(mutex, &desc->mux_lock) {
+		if (!gpio_range) {
+			/*
+			 * A pin should not be freed more times than allocated.
+			 */
+			if (WARN_ON(!desc->mux_usecount))
+				return NULL;
+			desc->mux_usecount--;
+			if (desc->mux_usecount)
+				return NULL;
+		}
+
+		if (gpio_range) {
+			owner = desc->gpio_owner;
+			desc->gpio_owner = NULL;
+		} else {
+			owner = desc->mux_owner;
+			desc->mux_owner = NULL;
+			desc->mux_setting = NULL;
+		}
 	}
 
 	/*
@@ -239,15 +275,6 @@ static const char *pin_free(struct pinctrl_dev *pctldev, int pin,
 	else if (ops->free)
 		ops->free(pctldev, pin);
 
-	if (gpio_range) {
-		owner = desc->gpio_owner;
-		desc->gpio_owner = NULL;
-	} else {
-		owner = desc->mux_owner;
-		desc->mux_owner = NULL;
-		desc->mux_setting = NULL;
-	}
-
 	module_put(pctldev->owner);
 
 	return owner;
@@ -329,7 +356,7 @@ static int pinmux_func_name_to_selector(struct pinctrl_dev *pctldev,
 	while (selector < nfuncs) {
 		const char *fname = ops->get_function_name(pctldev, selector);
 
-		if (!strcmp(function, fname))
+		if (fname && !strcmp(function, fname))
 			return selector;
 
 		selector++;
@@ -442,8 +469,7 @@ int pinmux_enable_setting(const struct pinctrl_setting *setting)
 			gname = pctlops->get_group_name(pctldev,
 						setting->data.mux.group);
 			dev_err_probe(pctldev->dev, ret,
-				"could not request pin %d (%s) from group %s "
-				" on device %s\n",
+				"could not request pin %d (%s) from group %s on device %s\n",
 				pins[i], pname, gname,
 				pinctrl_dev_get_name(pctldev));
 			goto err_pin_request;
@@ -459,7 +485,8 @@ int pinmux_enable_setting(const struct pinctrl_setting *setting)
 				 pins[i]);
 			continue;
 		}
-		desc->mux_setting = &(setting->data.mux);
+		scoped_guard(mutex, &desc->mux_lock)
+			desc->mux_setting = &(setting->data.mux);
 	}
 
 	ret = ops->set_mux(pctldev, setting->data.mux.func,
@@ -473,8 +500,10 @@ int pinmux_enable_setting(const struct pinctrl_setting *setting)
 err_set_mux:
 	for (i = 0; i < num_pins; i++) {
 		desc = pin_desc_get(pctldev, pins[i]);
-		if (desc)
-			desc->mux_setting = NULL;
+		if (desc) {
+			scoped_guard(mutex, &desc->mux_lock)
+				desc->mux_setting = NULL;
+		}
 	}
 err_pin_request:
 	/* On error release all taken pins */
@@ -493,6 +522,7 @@ void pinmux_disable_setting(const struct pinctrl_setting *setting)
 	unsigned int num_pins = 0;
 	int i;
 	struct pin_desc *desc;
+	bool is_equal;
 
 	if (pctlops->get_group_pins)
 		ret = pctlops->get_group_pins(pctldev, setting->data.mux.group,
@@ -518,7 +548,10 @@ void pinmux_disable_setting(const struct pinctrl_setting *setting)
 				 pins[i]);
 			continue;
 		}
-		if (desc->mux_setting == &(setting->data.mux)) {
+		scoped_guard(mutex, &desc->mux_lock)
+			is_equal = (desc->mux_setting == &(setting->data.mux));
+
+		if (is_equal) {
 			pin_free(pctldev, pins[i], NULL);
 		} else {
 			const char *gname;
@@ -526,9 +559,7 @@ void pinmux_disable_setting(const struct pinctrl_setting *setting)
 			gname = pctlops->get_group_name(pctldev,
 						setting->data.mux.group);
 			dev_warn(pctldev->dev,
-				 "not freeing pin %d (%s) as part of "
-				 "deactivating group %s - it is already "
-				 "used for some other setting",
+				 "not freeing pin %d (%s) as part of deactivating group %s - it is already used for some other setting",
 				 pins[i], desc->name, gname);
 		}
 	}
@@ -611,40 +642,42 @@ static int pinmux_pins_show(struct seq_file *s, void *what)
 		if (desc == NULL)
 			continue;
 
-		if (desc->mux_owner &&
-		    !strcmp(desc->mux_owner, pinctrl_dev_get_name(pctldev)))
-			is_hog = true;
-
-		if (pmxops->strict) {
-			if (desc->mux_owner)
-				seq_printf(s, "pin %d (%s): device %s%s",
-					   pin, desc->name, desc->mux_owner,
+		scoped_guard(mutex, &desc->mux_lock) {
+			if (desc->mux_owner &&
+			    !strcmp(desc->mux_owner, pinctrl_dev_get_name(pctldev)))
+				is_hog = true;
+
+			if (pmxops->strict) {
+				if (desc->mux_owner)
+					seq_printf(s, "pin %d (%s): device %s%s",
+						   pin, desc->name, desc->mux_owner,
+						   is_hog ? " (HOG)" : "");
+				else if (desc->gpio_owner)
+					seq_printf(s, "pin %d (%s): GPIO %s",
+						   pin, desc->name, desc->gpio_owner);
+				else
+					seq_printf(s, "pin %d (%s): UNCLAIMED",
+						   pin, desc->name);
+			} else {
+				/* For non-strict controllers */
+				seq_printf(s, "pin %d (%s): %s %s%s", pin, desc->name,
+					   desc->mux_owner ? desc->mux_owner
+					   : "(MUX UNCLAIMED)",
+					   desc->gpio_owner ? desc->gpio_owner
+					   : "(GPIO UNCLAIMED)",
 					   is_hog ? " (HOG)" : "");
-			else if (desc->gpio_owner)
-				seq_printf(s, "pin %d (%s): GPIO %s",
-					   pin, desc->name, desc->gpio_owner);
+			}
+
+			/* If mux: print function+group claiming the pin */
+			if (desc->mux_setting)
+				seq_printf(s, " function %s group %s\n",
+					   pmxops->get_function_name(pctldev,
+						desc->mux_setting->func),
+					   pctlops->get_group_name(pctldev,
+						desc->mux_setting->group));
 			else
-				seq_printf(s, "pin %d (%s): UNCLAIMED",
-					   pin, desc->name);
-		} else {
-			/* For non-strict controllers */
-			seq_printf(s, "pin %d (%s): %s %s%s", pin, desc->name,
-				   desc->mux_owner ? desc->mux_owner
-				   : "(MUX UNCLAIMED)",
-				   desc->gpio_owner ? desc->gpio_owner
-				   : "(GPIO UNCLAIMED)",
-				   is_hog ? " (HOG)" : "");
+				seq_putc(s, '\n');
 		}
-
-		/* If mux: print function+group claiming the pin */
-		if (desc->mux_setting)
-			seq_printf(s, " function %s group %s\n",
-				   pmxops->get_function_name(pctldev,
-					desc->mux_setting->func),
-				   pctlops->get_group_name(pctldev,
-					desc->mux_setting->group));
-		else
-			seq_putc(s, '\n');
 	}
 
 	mutex_unlock(&pctldev->mutex);
@@ -796,7 +829,7 @@ pinmux_generic_get_function_name(struct pinctrl_dev *pctldev,
 	if (!function)
 		return NULL;
 
-	return function->name;
+	return function->func->name;
 }
 EXPORT_SYMBOL_GPL(pinmux_generic_get_function_name);
 
@@ -805,12 +838,12 @@ EXPORT_SYMBOL_GPL(pinmux_generic_get_function_name);
  * @pctldev: pin controller device
  * @selector: function number
  * @groups: array of pin groups
- * @num_groups: number of pin groups
+ * @ngroups: number of pin groups
  */
 int pinmux_generic_get_function_groups(struct pinctrl_dev *pctldev,
 				       unsigned int selector,
 				       const char * const **groups,
-				       unsigned int * const num_groups)
+				       unsigned int * const ngroups)
 {
 	struct function_desc *function;
 
@@ -821,8 +854,8 @@ int pinmux_generic_get_function_groups(struct pinctrl_dev *pctldev,
 			__func__, selector);
 		return -EINVAL;
 	}
-	*groups = function->group_names;
-	*num_groups = function->num_group_names;
+	*groups = function->func->groups;
+	*ngroups = function->func->ngroups;
 
 	return 0;
 }
@@ -833,8 +866,8 @@ EXPORT_SYMBOL_GPL(pinmux_generic_get_function_groups);
  * @pctldev: pin controller device
  * @selector: function number
  */
-struct function_desc *pinmux_generic_get_function(struct pinctrl_dev *pctldev,
-						  unsigned int selector)
+const struct function_desc *
+pinmux_generic_get_function(struct pinctrl_dev *pctldev, unsigned int selector)
 {
 	struct function_desc *function;
 
@@ -848,26 +881,59 @@ struct function_desc *pinmux_generic_get_function(struct pinctrl_dev *pctldev,
 EXPORT_SYMBOL_GPL(pinmux_generic_get_function);
 
 /**
+ * pinmux_generic_function_is_gpio() - returns true if given function is a GPIO
+ * @pctldev: pin controller device
+ * @selector: function number
+ *
+ * Returns:
+ * True if given function is a GPIO, false otherwise.
+ */
+bool pinmux_generic_function_is_gpio(struct pinctrl_dev *pctldev,
+				     unsigned int selector)
+{
+	struct function_desc *function;
+
+	function = radix_tree_lookup(&pctldev->pin_function_tree, selector);
+	if (!function)
+		return false;
+
+	return function->func->flags & PINFUNCTION_FLAG_GPIO;
+}
+EXPORT_SYMBOL_GPL(pinmux_generic_function_is_gpio);
+
+/**
  * pinmux_generic_add_function() - adds a function group
  * @pctldev: pin controller device
  * @name: name of the function
  * @groups: array of pin groups
- * @num_groups: number of pin groups
+ * @ngroups: number of pin groups
  * @data: pin controller driver specific data
  */
 int pinmux_generic_add_function(struct pinctrl_dev *pctldev,
 				const char *name,
 				const char * const *groups,
-				const unsigned int num_groups,
+				const unsigned int ngroups,
 				void *data)
 {
+	struct pinfunction func = PINCTRL_PINFUNCTION(name, groups, ngroups);
+
+	return pinmux_generic_add_pinfunction(pctldev, &func, data);
+}
+EXPORT_SYMBOL_GPL(pinmux_generic_add_function);
+
+/**
+ * pinmux_generic_add_pinfunction() - adds a function group
+ * @pctldev: pin controller device
+ * @func: pinfunction structure describing the function group
+ * @data: pin controller driver specific data
+ */
+int pinmux_generic_add_pinfunction(struct pinctrl_dev *pctldev,
+				   const struct pinfunction *func, void *data)
+{
 	struct function_desc *function;
 	int selector, error;
 
-	if (!name)
-		return -EINVAL;
-
-	selector = pinmux_func_name_to_selector(pctldev, name);
+	selector = pinmux_func_name_to_selector(pctldev, func->name);
 	if (selector >= 0)
 		return selector;
 
@@ -877,9 +943,17 @@ int pinmux_generic_add_function(struct pinctrl_dev *pctldev,
 	if (!function)
 		return -ENOMEM;
 
-	function->name = name;
-	function->group_names = groups;
-	function->num_group_names = num_groups;
+	/*
+	 * FIXME: It's generally a bad idea to use devres in subsystem core
+	 * code - managed interfaces are aimed at drivers - but pinctrl already
+	 * uses it all over the place so it's a larger piece of technical debt
+	 * to fix.
+	 */
+	function->func = devm_kmemdup_const(pctldev->dev, func,
+					    sizeof(*func), GFP_KERNEL);
+	if (!function->func)
+		return -ENOMEM;
+
 	function->data = data;
 
 	error = radix_tree_insert(&pctldev->pin_function_tree, selector, function);
@@ -890,7 +964,7 @@ int pinmux_generic_add_function(struct pinctrl_dev *pctldev,
 
 	return selector;
 }
-EXPORT_SYMBOL_GPL(pinmux_generic_add_function);
+EXPORT_SYMBOL_GPL(pinmux_generic_add_pinfunction);
 
 /**
  * pinmux_generic_remove_function() - removes a numbered function