[PATCH] regmap: add regmap_update_bits variant to autoshift mask

[PATCH] regmap: add regmap_update_bits variant to autoshift mask

[Brandon Cheo Fusi]

This is both trivial and very handy in cases where the mask contains a single
contiguous group (GENMASK(hi, lo)), so users don't have to always adjust val.

Signed-off-by: Brandon Cheo Fusi <fusibrandon13@gmail.com>
---
 include/linux/regmap.h | 69 ++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 69 insertions(+)

diff --git a/include/linux/regmap.h b/include/linux/regmap.h
index c9182a477..373f00f30 100644
--- a/include/linux/regmap.h
+++ b/include/linux/regmap.h
@@ -1241,12 +1241,28 @@ static inline int regmap_update_bits(struct regmap *map, unsigned int reg,
 	return regmap_update_bits_base(map, reg, mask, val, NULL, false, false);
 }
 
+static inline int regmap_update_bits_autoshift_val(struct regmap *map, unsigned int reg,
+				     unsigned int mask, unsigned int val)
+{
+	val <<= (ffs(mask) - 1);
+
+	return regmap_update_bits_base(map, reg, mask, val, NULL, false, false);
+}
+
 static inline int regmap_update_bits_async(struct regmap *map, unsigned int reg,
 					   unsigned int mask, unsigned int val)
 {
 	return regmap_update_bits_base(map, reg, mask, val, NULL, true, false);
 }
 
+static inline int regmap_update_bits_autoshift_val_async(struct regmap *map,
+					   unsigned int reg, unsigned int mask, unsigned int val)
+{
+	val <<= (ffs(mask) - 1);
+
+	return regmap_update_bits_base(map, reg, mask, val, NULL, true, false);
+}
+
 static inline int regmap_update_bits_check(struct regmap *map, unsigned int reg,
 					   unsigned int mask, unsigned int val,
 					   bool *change)
@@ -1255,6 +1271,16 @@ static inline int regmap_update_bits_check(struct regmap *map, unsigned int reg,
 				       change, false, false);
 }
 
+static inline int regmap_update_bits_autoshift_val_check(struct regmap *map,
+					   unsigned int reg, unsigned int mask, unsigned int val,
+					   bool *change)
+{
+	val <<= (ffs(mask) - 1);
+
+	return regmap_update_bits_base(map, reg, mask, val,
+				       change, false, false);
+}
+
 static inline int
 regmap_update_bits_check_async(struct regmap *map, unsigned int reg,
 			       unsigned int mask, unsigned int val,
@@ -1264,6 +1290,17 @@ regmap_update_bits_check_async(struct regmap *map, unsigned int reg,
 				       change, true, false);
 }
 
+static inline int
+regmap_update_bits_autoshift_val_check_async(struct regmap *map,
+				   unsigned int reg, unsigned int mask, unsigned int val,
+			       bool *change)
+{
+	val <<= (ffs(mask) - 1);
+
+	return regmap_update_bits_base(map, reg, mask, val,
+				       change, true, false);
+}
+
 static inline int regmap_write_bits(struct regmap *map, unsigned int reg,
 				    unsigned int mask, unsigned int val)
 {
@@ -1808,6 +1845,13 @@ static inline int regmap_update_bits(struct regmap *map, unsigned int reg,
 	return -EINVAL;
 }
 
+static inline int regmap_update_bits_autoshift_val(struct regmap *map,
+					 unsigned int reg, unsigned int mask, unsigned int val)
+{
+	WARN_ONCE(1, "regmap API is disabled");
+	return -EINVAL;
+}
+
 static inline int regmap_update_bits_async(struct regmap *map, unsigned int reg,
 					   unsigned int mask, unsigned int val)
 {
@@ -1815,6 +1859,14 @@ static inline int regmap_update_bits_async(struct regmap *map, unsigned int reg,
 	return -EINVAL;
 }
 
+static inline int regmap_update_bits_autoshift_val_async(struct regmap *map,
+					   unsigned int reg, unsigned int mask, unsigned int val)
+{
+	WARN_ONCE(1, "regmap API is disabled");
+	return -EINVAL;
+}
+
+
 static inline int regmap_update_bits_check(struct regmap *map, unsigned int reg,
 					   unsigned int mask, unsigned int val,
 					   bool *change)
@@ -1823,6 +1875,14 @@ static inline int regmap_update_bits_check(struct regmap *map, unsigned int reg,
 	return -EINVAL;
 }
 
+static inline int regmap_update_bits_autoshift_val_check(struct regmap *map,
+					   unsigned int reg, unsigned int mask, unsigned int val,
+					   bool *change)
+{
+	WARN_ONCE(1, "regmap API is disabled");
+	return -EINVAL;
+}
+
 static inline int
 regmap_update_bits_check_async(struct regmap *map, unsigned int reg,
 			       unsigned int mask, unsigned int val,
@@ -1832,6 +1892,15 @@ regmap_update_bits_check_async(struct regmap *map, unsigned int reg,
 	return -EINVAL;
 }
 
+static inline int
+regmap_update_bits_autoshift_val_check_async(struct regmap *map,
+				   unsigned int reg, unsigned int mask, unsigned int val,
+			       bool *change)
+{
+	WARN_ONCE(1, "regmap API is disabled");
+	return -EINVAL;
+}
+
 static inline int regmap_write_bits(struct regmap *map, unsigned int reg,
 				    unsigned int mask, unsigned int val)
 {
-- 
2.30.2

Re: [PATCH] regmap: add regmap_update_bits variant to autoshift mask

[Mark Brown]

[-- Attachment #1: Type: text/plain, Size: 402 bytes --]

On Mon, Nov 06, 2023 at 05:34:06PM +0100, Brandon Cheo Fusi wrote:

> +static inline int regmap_update_bits_autoshift_val(struct regmap *map, unsigned int reg,
> +				     unsigned int mask, unsigned int val)
> +{

Really not a fan of the name here, and in any case if the shifting of
the value is an issue wouldn't this be a good case for using a field?

Please also add kunit testcases for new APIs.

[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 488 bytes --]

Fwd: [PATCH] regmap: add regmap_update_bits variant to autoshift mask

[Brandon Cheo Fusi]

---------- Forwarded message ---------
From: Brandon Cheo Fusi <fusibrandon13@gmail.com>
Date: Wed, Nov 8, 2023 at 11:18 AM
Subject: Re: [PATCH] regmap: add regmap_update_bits variant to autoshift mask
To: Mark Brown <broonie@kernel.org>


On Mon, Nov 6, 2023 at 5:54 PM Mark Brown <broonie@kernel.org> wrote:
>
> On Mon, Nov 06, 2023 at 05:34:06PM +0100, Brandon Cheo Fusi wrote:
>
> > +static inline int regmap_update_bits_autoshift_val(struct regmap *map, unsigned int reg,
> > +                                  unsigned int mask, unsigned int val)
> > +{
>
> Really not a fan of the name here, and in any case if the shifting of
> the value is an issue wouldn't this be a good case for using a field?

True. But all this does is handle the special and very common case of
'regmap_update_bits(regmap, reg, GENMASK(hi,lo), val)' where [hi,lo]
isn't at the bottom of reg. Most drivers don't resort to allocating
regmap_fields for each bit range they manipulate.

>
> Please also add kunit testcases for new APIs.

I'd be happy to send a v2 with kunit testcases, if you think the API is
worthwhile.