// SPDX-License-Identifier: GPL-2.0-or-later/* * phy-common-props.c  --  Common PHY properties * * Copyright 2025-2026 NXP */#include <linux/export.h>#include <linux/fwnode.h>#include <linux/phy/phy-common-props.h>#include <linux/printk.h>#include <linux/property.h>#include <linux/slab.h> /** * fwnode_get_u32_prop_for_name - Find u32 property by name, or default value * @fwnode: Pointer to firmware node, or NULL to use @default_val * @name: Property name used as lookup key in @names_title (must not be NULL) * @props_title: Name of u32 array property holding values * @names_title: Name of string array property holding lookup keys * @default_val: Default value if @fwnode is NULL or @props_title is empty * @val: Pointer to store the returned value * * This function retrieves a u32 value from @props_title based on a name lookup * in @names_title. The value stored in @val is determined as follows: * * - If @fwnode is NULL or @props_title is empty: @default_val is used * - If @props_title has exactly one element and @names_title is empty: *   that element is used * - Otherwise: @val is set to the element at the same index where @name is *   found in @names_title. * - If @name is not found, the function looks for a "default" entry in *   @names_title and uses the corresponding value from @props_title * * When both @props_title and @names_title are present, they must have the * same number of elements (except when @props_title has exactly one element). * * Return: zero on success, negative error on failure. */static int fwnode_get_u32_prop_for_name(struct fwnode_handle *fwnode,					const char *name,					const char *props_title,					const char *names_title,					unsigned int default_val,					unsigned int *val){	int err, n_props, n_names, idx;	u32 *props; 	if (!name) {		pr_err("Lookup key inside \"%s\" is mandatory\n", names_title);		return -EINVAL;	} 	n_props = fwnode_property_count_u32(fwnode, props_title);	if (n_props <= 0) {		/* fwnode is NULL, or is missing requested property */		*val = default_val;		return 0;	} 	n_names = fwnode_property_string_array_count(fwnode, names_title);	if (n_names >= 0 && n_props != n_names) {		pr_err("%pfw mismatch between \"%s\" and \"%s\" property count (%d vs %d)\n",		       fwnode, props_title, names_title, n_props, n_names);		return -EINVAL;	} 	idx = fwnode_property_match_string(fwnode, names_title, name);	if (idx < 0)		idx = fwnode_property_match_string(fwnode, names_title, "default");	/*	 * If the mode name is missing, it can only mean the specified property	 * is the default one for all modes, so reject any other property count	 * than 1.	 */	if (idx < 0 && n_props != 1) {		pr_err("%pfw \"%s \" property has %d elements, but cannot find \"%s\" in \"%s\" and there is no default value\n",		       fwnode, props_title, n_props, name, names_title);		return -EINVAL;	} 	if (n_props == 1) {		err = fwnode_property_read_u32(fwnode, props_title, val);		if (err)			return err; 		return 0;	} 	/* We implicitly know idx >= 0 here */	props = kcalloc(n_props, sizeof(*props), GFP_KERNEL);	if (!props)		return -ENOMEM; 	err = fwnode_property_read_u32_array(fwnode, props_title, props, n_props);	if (err >= 0)		*val = props[idx]; 	kfree(props); 	return err;} static int phy_get_polarity_for_mode(struct fwnode_handle *fwnode,				     const char *mode_name,				     unsigned int supported,				     unsigned int default_val,				     const char *polarity_prop,				     const char *names_prop,				     unsigned int *val){	int err; 	err = fwnode_get_u32_prop_for_name(fwnode, mode_name, polarity_prop,					   names_prop, default_val, val);	if (err)		return err; 	if (!(supported & BIT(*val))) {		pr_err("%d is not a supported value for %pfw '%s' element '%s'\n",		       *val, fwnode, polarity_prop, mode_name);		err = -EOPNOTSUPP;	} 	return err;} /** * phy_get_rx_polarity - Get RX polarity for PHY differential lane * @fwnode: Pointer to the PHY's firmware node. * @mode_name: The name of the PHY mode to look up. * @supported: Bit mask of PHY_POL_NORMAL, PHY_POL_INVERT and PHY_POL_AUTO * @default_val: Default polarity value if property is missing * @val: Pointer to returned polarity. * * Return: zero on success, negative error on failure. */int __must_check phy_get_rx_polarity(struct fwnode_handle *fwnode,				     const char *mode_name,				     unsigned int supported,				     unsigned int default_val,				     unsigned int *val){	return phy_get_polarity_for_mode(fwnode, mode_name, supported,					 default_val, "rx-polarity",					 "rx-polarity-names", val);}EXPORT_SYMBOL_GPL(phy_get_rx_polarity); /** * phy_get_tx_polarity - Get TX polarity for PHY differential lane * @fwnode: Pointer to the PHY's firmware node. * @mode_name: The name of the PHY mode to look up. * @supported: Bit mask of PHY_POL_NORMAL and PHY_POL_INVERT * @default_val: Default polarity value if property is missing * @val: Pointer to returned polarity. * * Return: zero on success, negative error on failure. */int __must_check phy_get_tx_polarity(struct fwnode_handle *fwnode,				     const char *mode_name, unsigned int supported,				     unsigned int default_val, unsigned int *val){	return phy_get_polarity_for_mode(fwnode, mode_name, supported,					 default_val, "tx-polarity",					 "tx-polarity-names", val);}EXPORT_SYMBOL_GPL(phy_get_tx_polarity); /** * phy_get_manual_rx_polarity - Get manual RX polarity for PHY differential lane * @fwnode: Pointer to the PHY's firmware node. * @mode_name: The name of the PHY mode to look up. * @val: Pointer to returned polarity. * * Helper for PHYs which do not support protocols with automatic RX polarity * detection and correction. * * Return: zero on success, negative error on failure. */int __must_check phy_get_manual_rx_polarity(struct fwnode_handle *fwnode,					    const char *mode_name,					    unsigned int *val){	return phy_get_rx_polarity(fwnode, mode_name,				   BIT(PHY_POL_NORMAL) | BIT(PHY_POL_INVERT),				   PHY_POL_NORMAL, val);}EXPORT_SYMBOL_GPL(phy_get_manual_rx_polarity); /** * phy_get_manual_tx_polarity - Get manual TX polarity for PHY differential lane * @fwnode: Pointer to the PHY's firmware node. * @mode_name: The name of the PHY mode to look up. * @val: Pointer to returned polarity. * * Helper for PHYs without any custom default value for the TX polarity. * * Return: zero on success, negative error on failure. */int __must_check phy_get_manual_tx_polarity(struct fwnode_handle *fwnode,					    const char *mode_name,					    unsigned int *val){	return phy_get_tx_polarity(fwnode, mode_name,				   BIT(PHY_POL_NORMAL) | BIT(PHY_POL_INVERT),				   PHY_POL_NORMAL, val);}EXPORT_SYMBOL_GPL(phy_get_manual_tx_polarity);