netdev - [PATCH v3 1/2] regmap: provide helpers for simple bit operations

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20200528154503.26304-2-brgl@bgdev.pl>
Date:   Thu, 28 May 2020 17:45:02 +0200
From:   Bartosz Golaszewski <brgl@...ev.pl>
To:     John Crispin <john@...ozen.org>,
        Sean Wang <sean.wang@...iatek.com>,
        Mark Lee <Mark-MC.Lee@...iatek.com>,
        "David S . Miller" <davem@...emloft.net>,
        Jakub Kicinski <kuba@...nel.org>,
        Matthias Brugger <matthias.bgg@...il.com>,
        Mark Brown <broonie@...nel.org>
Cc:     netdev@...r.kernel.org, linux-arm-kernel@...ts.infradead.org,
        linux-mediatek@...ts.infradead.org, linux-kernel@...r.kernel.org,
        Fabien Parent <fparent@...libre.com>,
        Stephane Le Provost <stephane.leprovost@...iatek.com>,
        Pedro Tsai <pedro.tsai@...iatek.com>,
        Andrew Perepech <andrew.perepech@...iatek.com>,
        Bartosz Golaszewski <bgolaszewski@...libre.com>
Subject: [PATCH v3 1/2] regmap: provide helpers for simple bit operations

From: Bartosz Golaszewski <bgolaszewski@...libre.com>

In many instances regmap_update_bits() is used for simple bit setting
and clearing. In these cases the last argument is redundant and we can
hide it with a static inline function.

This adds three new helpers for simple bit operations: set_bits,
clear_bits and test_bits (the last one defined as a regular function).

Signed-off-by: Bartosz Golaszewski <bgolaszewski@...libre.com>
---
 drivers/base/regmap/regmap.c | 22 ++++++++++++++++++++++
 include/linux/regmap.h       | 36 ++++++++++++++++++++++++++++++++++++
 2 files changed, 58 insertions(+)

diff --git a/drivers/base/regmap/regmap.c b/drivers/base/regmap/regmap.c
index 59f911e57719..4ad5c5adc0a3 100644
--- a/drivers/base/regmap/regmap.c
+++ b/drivers/base/regmap/regmap.c
@@ -2936,6 +2936,28 @@ int regmap_update_bits_base(struct regmap *map, unsigned int reg,
 }
 EXPORT_SYMBOL_GPL(regmap_update_bits_base);
 
+/**
+ * regmap_test_bits() - Check if all specified bits are set in a register.
+ *
+ * @map: Register map to operate on
+ * @reg: Register to read from
+ * @bits: Bits to test
+ *
+ * Returns -1 if the underlying regmap_read() fails, 0 if at least one of the
+ * tested bits is not set and 1 if all tested bits are set.
+ */
+int regmap_test_bits(struct regmap *map, unsigned int reg, unsigned int bits)
+{
+	unsigned int val, ret;
+
+	ret = regmap_read(map, reg, &val);
+	if (ret)
+		return ret;
+
+	return (val & bits) == bits;
+}
+EXPORT_SYMBOL_GPL(regmap_test_bits);
+
 void regmap_async_complete_cb(struct regmap_async *async, int ret)
 {
 	struct regmap *map = async->map;
diff --git a/include/linux/regmap.h b/include/linux/regmap.h
index 40b07168fd8e..ddf0baff195d 100644
--- a/include/linux/regmap.h
+++ b/include/linux/regmap.h
@@ -1111,6 +1111,21 @@ bool regmap_reg_in_ranges(unsigned int reg,
 			  const struct regmap_range *ranges,
 			  unsigned int nranges);
 
+static inline int regmap_set_bits(struct regmap *map,
+				  unsigned int reg, unsigned int bits)
+{
+	return regmap_update_bits_base(map, reg, bits, bits,
+				       NULL, false, false);
+}
+
+static inline int regmap_clear_bits(struct regmap *map,
+				    unsigned int reg, unsigned int bits)
+{
+	return regmap_update_bits_base(map, reg, bits, 0, NULL, false, false);
+}
+
+int regmap_test_bits(struct regmap *map, unsigned int reg, unsigned int bits);
+
 /**
  * struct reg_field - Description of an register field
  *
@@ -1410,6 +1425,27 @@ static inline int regmap_update_bits_base(struct regmap *map, unsigned int reg,
 	return -EINVAL;
 }
 
+static inline int regmap_set_bits(struct regmap *map,
+				  unsigned int reg, unsigned int bits)
+{
+	WARN_ONCE(1, "regmap API is disabled");
+	return -EINVAL;
+}
+
+static inline int regmap_clear_bits(struct regmap *map,
+				    unsigned int reg, unsigned int bits)
+{
+	WARN_ONCE(1, "regmap API is disabled");
+	return -EINVAL;
+}
+
+static inline int regmap_test_bits(struct regmap *map,
+				   unsigned int reg, unsigned int bits)
+{
+	WARN_ONCE(1, "regmap API is disabled");
+	return -EINVAL;
+}
+
 static inline int regmap_field_update_bits_base(struct regmap_field *field,
 					unsigned int mask, unsigned int val,
 					bool *change, bool async, bool force)
-- 
2.26.1