From 5728c92ae112301936006c5e305677beb1a7f578 Mon Sep 17 00:00:00 2001 From: "Rob Herring (Arm)" Date: Fri, 24 Jan 2025 13:16:44 -0600 Subject: [PATCH] mfd: syscon: Restore device_node_to_regmap() for non-syscon nodes MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Commit ba5095ebbc7a ("mfd: syscon: Allow syscon nodes without a "syscon" compatible") broke drivers which call device_node_to_regmap() on nodes without a "syscon" compatible. Restore the prior behavior for device_node_to_regmap(). This also makes using device_node_to_regmap() incompatible with of_syscon_register_regmap() again, so add kerneldoc for device_node_to_regmap() and syscon_node_to_regmap() to make it clear how and when each one should be used. Fixes: ba5095ebbc7a ("mfd: syscon: Allow syscon nodes without a "syscon" compatible") Reported-by: Vaishnav Achath Signed-off-by: Rob Herring (Arm) Reviewed-by: Daniel Golle Reviewed-by: AngeloGioacchino Del Regno Tested-by: Chen-Yu Tsai Tested-by: Nishanth Menon Tested-by: Daniel Golle Tested-by: Frank Wunderlich Tested-by: Dhruva Gole Tested-by: NĂ­colas F. R. A. Prado Tested-by: AngeloGioacchino Del Regno Link: https://lore.kernel.org/r/20250124191644.2309790-1-robh@kernel.org Signed-off-by: Lee Jones --- drivers/mfd/syscon.c | 29 ++++++++++++++++++++++++++--- 1 file changed, 26 insertions(+), 3 deletions(-) diff --git a/drivers/mfd/syscon.c b/drivers/mfd/syscon.c index 226915ca3c93..aa4a9940b569 100644 --- a/drivers/mfd/syscon.c +++ b/drivers/mfd/syscon.c @@ -159,6 +159,7 @@ err_regmap: } static struct regmap *device_node_get_regmap(struct device_node *np, + bool create_regmap, bool check_res) { struct syscon *entry, *syscon = NULL; @@ -172,7 +173,7 @@ static struct regmap *device_node_get_regmap(struct device_node *np, } if (!syscon) { - if (of_device_is_compatible(np, "syscon")) + if (create_regmap) syscon = of_syscon_register(np, check_res); else syscon = ERR_PTR(-EINVAL); @@ -233,15 +234,37 @@ err_unlock: } EXPORT_SYMBOL_GPL(of_syscon_register_regmap); +/** + * device_node_to_regmap() - Get or create a regmap for specified device node + * @np: Device tree node + * + * Get a regmap for the specified device node. If there's not an existing + * regmap, then one is instantiated. This function should not be used if the + * device node has a custom regmap driver or has resources (clocks, resets) to + * be managed. Use syscon_node_to_regmap() instead for those cases. + * + * Return: regmap ptr on success, negative error code on failure. + */ struct regmap *device_node_to_regmap(struct device_node *np) { - return device_node_get_regmap(np, false); + return device_node_get_regmap(np, true, false); } EXPORT_SYMBOL_GPL(device_node_to_regmap); +/** + * syscon_node_to_regmap() - Get or create a regmap for specified syscon device node + * @np: Device tree node + * + * Get a regmap for the specified device node. If there's not an existing + * regmap, then one is instantiated if the node is a generic "syscon". This + * function is safe to use for a syscon registered with + * of_syscon_register_regmap(). + * + * Return: regmap ptr on success, negative error code on failure. + */ struct regmap *syscon_node_to_regmap(struct device_node *np) { - return device_node_get_regmap(np, true); + return device_node_get_regmap(np, of_device_is_compatible(np, "syscon"), true); } EXPORT_SYMBOL_GPL(syscon_node_to_regmap);