// SPDX-License-Identifier: GPL-2.0-or-later /* * phy-common-props.c -- Common PHY properties * * Copyright 2025-2026 NXP */ #include #include #include #include #include #include /** * 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);