linux-kernel - [PATCH v2 1/4] regmap: provide regmap_field helpers for simple bit operations

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Message-ID: <180eeba3811.f7218bc260169.7323954027713751119@zohomail.com>
Date:   Sun, 22 May 2022 19:23:43 -0700
From:   Li Chen <lchen.firstlove@...omail.com>
To:     "Mark Brown" <broonie@...nel.org>,
        "linux-kernel" <linux-kernel@...r.kernel.org>,
        "Greg Kroah-Hartman" <gregkh@...uxfoundation.org>,
        "Rafael J. Wysocki" <rafael@...nel.org>,
        "linux-gpio" <linux-gpio@...r.kernel.org>,
        "Linus Walleij" <linus.walleij@...aro.org>,
        "linux-arm-kernel" <linux-arm-kernel@...ts.infradead.org>,
        "Patrice Chotard" <patrice.chotard@...s.st.com>,
        "linux-sunxi" <linux-sunxi@...ts.linux.dev>,
        "Liam Girdwood" <lgirdwood@...il.com>,
        "Jaroslav Kysela" <perex@...ex.cz>,
        "Takashi Iwai" <tiwai@...e.com>, "Chen-Yu Tsai" <wens@...e.org>,
        "Jernej Skrabec" <jernej.skrabec@...il.com>,
        "Samuel Holland" <samuel@...lland.org>,
        "Philipp Zabel" <p.zabel@...gutronix.de>
Subject: [PATCH v2 1/4] regmap: provide regmap_field helpers for simple bit
  operations

From: Li Chen <lchen@...arella.com>

We have set/clear/test operations for regmap, but not for regmap_field yet.
So let's introduce regmap_field helpers too.

In many instances regmap_field_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: Li Chen <lchen@...arella.com>
---
 drivers/base/regmap/regmap.c | 22 +++++++++++++++++++++
 include/linux/regmap.h       | 37 ++++++++++++++++++++++++++++++++++++
 2 files changed, 59 insertions(+)

diff --git a/drivers/base/regmap/regmap.c b/drivers/base/regmap/regmap.c
index 5e12f7cb5147..a37d6041b7bd 100644
--- a/drivers/base/regmap/regmap.c
+++ b/drivers/base/regmap/regmap.c
@@ -2208,6 +2208,28 @@ int regmap_field_update_bits_base(struct regmap_field *field,
 }
 EXPORT_SYMBOL_GPL(regmap_field_update_bits_base);
 
+/**
+ * regmap_field_test_bits() - Check if all specified bits are set in a
+ *                            register field.
+ *
+ * @field: Register field to operate on
+ * @bits: Bits to test
+ *
+ * Returns -1 if the underlying regmap_field_read() fails, 0 if at least one of the
+ * tested bits is not set and 1 if all tested bits are set.
+ */
+int regmap_field_test_bits(struct regmap_field *field, unsigned int bits)
+{
+	unsigned int val, ret;
+
+	ret = regmap_field_read(field, &val);
+	if (ret)
+		return ret;
+
+	return (val & bits) == bits;
+}
+EXPORT_SYMBOL_GPL(regmap_field_test_bits);
+
 /**
  * regmap_fields_update_bits_base() - Perform a read/modify/write cycle a
  *                                    register field with port ID
diff --git a/include/linux/regmap.h b/include/linux/regmap.h
index de81a94d7b30..10b410734d9e 100644
--- a/include/linux/regmap.h
+++ b/include/linux/regmap.h
@@ -1324,6 +1324,22 @@ static inline int regmap_field_update_bits(struct regmap_field *field,
 					     NULL, false, false);
 }
 
+static inline int regmap_field_set_bits(struct regmap_field *field,
+					unsigned int bits)
+{
+	return regmap_field_update_bits_base(field, bits, 0, NULL, false,
+					     false);
+}
+
+static inline int regmap_field_clear_bits(struct regmap_field *field,
+					  unsigned int bits)
+{
+	return regmap_field_update_bits_base(field, bits, bits, NULL, false,
+					     false);
+}
+
+int regmap_field_test_bits(struct regmap_field *field, unsigned int bits);
+
 static inline int
 regmap_field_force_update_bits(struct regmap_field *field,
 			       unsigned int mask, unsigned int val)
@@ -1757,6 +1773,27 @@ regmap_field_force_update_bits(struct regmap_field *field,
 	return -EINVAL;
 }
 
+static inline int regmap_field_set_bits(struct regmap_field *field,
+					unsigned int bits)
+{
+	WARN_ONCE(1, "regmap API is disabled");
+	return -EINVAL;
+}
+
+static inline int regmap_field_clear_bits(struct regmap_field *field,
+					  unsigned int bits)
+{
+	WARN_ONCE(1, "regmap API is disabled");
+	return -EINVAL;
+}
+
+static inline int regmap_field_test_bits(struct regmap_field *field,
+					 unsigned int bits)
+{
+	WARN_ONCE(1, "regmap API is disabled");
+	return -EINVAL;
+}
+
 static inline int regmap_fields_write(struct regmap_field *field,
 				      unsigned int id, unsigned int val)
 {
-- 
2.36.1