Patch "regmap-irq: Use the new num_config_regs property in regmap_add_irq_chip_fwnode" has been added to the 6.1-stable tree

[Sasha Levin <sashal@xxxxxxxxxx>]

This is a note to let you know that I've just added the patch titled

    regmap-irq: Use the new num_config_regs property in regmap_add_irq_chip_fwnode

to the 6.1-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     regmap-irq-use-the-new-num_config_regs-property-in-r.patch
and it can be found in the queue-6.1 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.



commit 93fb9ef110403b01e8ad53013615d4100b896b77
Author: Yassine Oudjana <y.oudjana@xxxxxxxxxxxxxx>
Date:   Mon Nov 7 23:21:14 2022 +0300

    regmap-irq: Use the new num_config_regs property in regmap_add_irq_chip_fwnode
    
    [ Upstream commit 84498d1fb35de6ab71bdfdb6270a464fb4a0951b ]
    
    Commit faa87ce9196d ("regmap-irq: Introduce config registers for irq
    types") added the num_config_regs, then commit 9edd4f5aee84 ("regmap-irq:
    Deprecate type registers and virtual registers") suggested to replace
    num_type_reg with it. However, regmap_add_irq_chip_fwnode wasn't modified
    to use the new property. Later on, commit 255a03bb1bb3 ("ASoC: wcd9335:
    Convert irq chip to config regs") removed the old num_type_reg property
    from the WCD9335 driver's struct regmap_irq_chip, causing a null pointer
    dereference in regmap_irq_set_type when it tried to index d->type_buf as
    it was never allocated in regmap_add_irq_chip_fwnode:
    
    [   39.199374] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000
    
    [   39.200006] Call trace:
    [   39.200014]  regmap_irq_set_type+0x84/0x1c0
    [   39.200026]  __irq_set_trigger+0x60/0x1c0
    [   39.200040]  __setup_irq+0x2f4/0x78c
    [   39.200051]  request_threaded_irq+0xe8/0x1a0
    
    Use num_config_regs in regmap_add_irq_chip_fwnode instead of num_type_reg,
    and fall back to it if num_config_regs isn't defined to maintain backward
    compatibility.
    
    Fixes: faa87ce9196d ("regmap-irq: Introduce config registers for irq types")
    Signed-off-by: Yassine Oudjana <y.oudjana@xxxxxxxxxxxxxx>
    Link: https://lore.kernel.org/r/20221107202114.823975-1-y.oudjana@xxxxxxxxxxxxxx
    Signed-off-by: Mark Brown <broonie@xxxxxxxxxx>
    Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>

diff --git a/drivers/base/regmap/regmap-irq.c b/drivers/base/regmap/regmap-irq.c
index 4ef9488d05cd..3de89795f584 100644
--- a/drivers/base/regmap/regmap-irq.c
+++ b/drivers/base/regmap/regmap-irq.c
@@ -722,6 +722,7 @@ int regmap_add_irq_chip_fwnode(struct fwnode_handle *fwnode,
 	int i;
 	int ret = -ENOMEM;
 	int num_type_reg;
+	int num_regs;
 	u32 reg;
 
 	if (chip->num_regs <= 0)
@@ -796,14 +797,20 @@ int regmap_add_irq_chip_fwnode(struct fwnode_handle *fwnode,
 			goto err_alloc;
 	}
 
-	num_type_reg = chip->type_in_mask ? chip->num_regs : chip->num_type_reg;
-	if (num_type_reg) {
-		d->type_buf_def = kcalloc(num_type_reg,
+	/*
+	 * Use num_config_regs if defined, otherwise fall back to num_type_reg
+	 * to maintain backward compatibility.
+	 */
+	num_type_reg = chip->num_config_regs ? chip->num_config_regs
+			: chip->num_type_reg;
+	num_regs = chip->type_in_mask ? chip->num_regs : num_type_reg;
+	if (num_regs) {
+		d->type_buf_def = kcalloc(num_regs,
 					  sizeof(*d->type_buf_def), GFP_KERNEL);
 		if (!d->type_buf_def)
 			goto err_alloc;
 
-		d->type_buf = kcalloc(num_type_reg, sizeof(*d->type_buf),
+		d->type_buf = kcalloc(num_regs, sizeof(*d->type_buf),
 				      GFP_KERNEL);
 		if (!d->type_buf)
 			goto err_alloc;