From: Dimitris Papastamos <dp@opensource.wolfsonmicro.com>
Date: Mon, 19 Sep 2011 13:34:01 +0000 (+0100)
Subject: regmap: Add the indexed cache support
X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=195af65ca92179ac2b524d35d732dc6fecec2744;p=mv-sheeva.git

regmap: Add the indexed cache support

This is the simplest form of a cache available in regcache.  Any
registers whose default value is 0 are ignored.  If any of those
registers are modified in the future, they will be placed in the
cache on demand.  The cache layout is essentially using the provided
register defaults by the regcache core directly and does not re-map
it to another representation.

Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
---

diff --git a/drivers/base/regmap/Makefile b/drivers/base/regmap/Makefile
index 2e103ea9a3a..418d151eb30 100644
--- a/drivers/base/regmap/Makefile
+++ b/drivers/base/regmap/Makefile
@@ -1,4 +1,4 @@
-obj-$(CONFIG_REGMAP) += regmap.o regcache.o
+obj-$(CONFIG_REGMAP) += regmap.o regcache.o regcache-indexed.o
 obj-$(CONFIG_DEBUG_FS) += regmap-debugfs.o
 obj-$(CONFIG_REGMAP_I2C) += regmap-i2c.o
 obj-$(CONFIG_REGMAP_SPI) += regmap-spi.o
diff --git a/drivers/base/regmap/internal.h b/drivers/base/regmap/internal.h
index 615f5581d5d..5bd5759efd5 100644
--- a/drivers/base/regmap/internal.h
+++ b/drivers/base/regmap/internal.h
@@ -118,4 +118,5 @@ int regcache_lookup_reg(struct regmap *map, unsigned int reg);
 int regcache_insert_reg(struct regmap *map, unsigned int reg,
 			unsigned int val);
 
+extern struct regcache_ops regcache_indexed_ops;
 #endif
diff --git a/drivers/base/regmap/regcache-indexed.c b/drivers/base/regmap/regcache-indexed.c
new file mode 100644
index 00000000000..ff8b44ce044
--- /dev/null
+++ b/drivers/base/regmap/regcache-indexed.c
@@ -0,0 +1,65 @@
+/*
+ * Register cache access API - indexed caching support
+ *
+ * Copyright 2011 Wolfson Microelectronics plc
+ *
+ * Author: Dimitris Papastamos <dp@opensource.wolfsonmicro.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/slab.h>
+
+#include "internal.h"
+
+static int regcache_indexed_read(struct regmap *map, unsigned int reg,
+				 unsigned int *value)
+{
+	int ret;
+
+	ret = regcache_lookup_reg(map, reg);
+	if (ret < 0)
+		*value = 0;
+	else
+		*value = map->reg_defaults[ret].def;
+	return 0;
+}
+
+static int regcache_indexed_write(struct regmap *map, unsigned int reg,
+				  unsigned int value)
+{
+	int ret;
+
+	ret = regcache_lookup_reg(map, reg);
+	if (ret < 0)
+		return regcache_insert_reg(map, reg, value);
+	map->reg_defaults[ret].def = value;
+	return 0;
+}
+
+static int regcache_indexed_sync(struct regmap *map)
+{
+	int i;
+	int ret;
+
+	for (i = 0; i < map->num_reg_defaults; i++) {
+		ret = regmap_write(map, map->reg_defaults[i].reg,
+				   map->reg_defaults[i].def);
+		if (ret < 0)
+			return ret;
+		dev_dbg(map->dev, "Synced register %#x, value %#x\n",
+			map->reg_defaults[i].reg,
+			map->reg_defaults[i].def);
+	}
+	return 0;
+}
+
+struct regcache_ops regcache_indexed_ops = {
+	.type = REGCACHE_INDEXED,
+	.name = "indexed",
+	.read = regcache_indexed_read,
+	.write = regcache_indexed_write,
+	.sync = regcache_indexed_sync
+};
diff --git a/drivers/base/regmap/regcache.c b/drivers/base/regmap/regcache.c
index 9575e4c5f34..22b73ec12fd 100644
--- a/drivers/base/regmap/regcache.c
+++ b/drivers/base/regmap/regcache.c
@@ -16,6 +16,7 @@
 #include "internal.h"
 
 static const struct regcache_ops *cache_types[] = {
+	&regcache_indexed_ops,
 };
 
 static int regcache_hw_init(struct regmap *map)
diff --git a/include/linux/regmap.h b/include/linux/regmap.h
index 9d802944929..ae6d3a4cee9 100644
--- a/include/linux/regmap.h
+++ b/include/linux/regmap.h
@@ -23,6 +23,7 @@ struct spi_device;
 /* An enum of all the supported cache types */
 enum regcache_type {
 	REGCACHE_NONE,
+	REGCACHE_INDEXED,
 };
 
 /**