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-rw-r--r--drivers/base/regmap/Makefile2
-rw-r--r--drivers/base/regmap/internal.h52
-rw-r--r--drivers/base/regmap/regcache.c304
-rw-r--r--include/linux/regmap.h15
4 files changed, 371 insertions, 2 deletions
diff --git a/drivers/base/regmap/Makefile b/drivers/base/regmap/Makefile
index 057c13f66a67..2e103ea9a3a0 100644
--- a/drivers/base/regmap/Makefile
+++ b/drivers/base/regmap/Makefile
@@ -1,4 +1,4 @@
-obj-$(CONFIG_REGMAP) += regmap.o
+obj-$(CONFIG_REGMAP) += regmap.o regcache.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 a98493cde5c3..615f5581d5db 100644
--- a/drivers/base/regmap/internal.h
+++ b/drivers/base/regmap/internal.h
@@ -17,6 +17,7 @@
#include <linux/fs.h>
struct regmap;
+struct regcache_ops;
struct regmap_format {
size_t buf_size;
@@ -49,6 +50,40 @@ struct regmap {
u8 read_flag_mask;
u8 write_flag_mask;
+
+ /* regcache specific members */
+ const struct regcache_ops *cache_ops;
+ enum regcache_type cache_type;
+
+ /* number of bytes in reg_defaults_raw */
+ unsigned int cache_size_raw;
+ /* number of bytes per word in reg_defaults_raw */
+ unsigned int cache_word_size;
+ /* number of entries in reg_defaults */
+ unsigned int num_reg_defaults;
+ /* number of entries in reg_defaults_raw */
+ unsigned int num_reg_defaults_raw;
+
+ /* if set, only the cache is modified not the HW */
+ unsigned int cache_only:1;
+ /* if set, only the HW is modified not the cache */
+ unsigned int cache_bypass:1;
+ /* if set, remember to free reg_defaults_raw */
+ unsigned int cache_free:1;
+
+ struct reg_default *reg_defaults;
+ const void *reg_defaults_raw;
+ void *cache;
+};
+
+struct regcache_ops {
+ const char *name;
+ enum regcache_type type;
+ int (*init)(struct regmap *map);
+ int (*exit)(struct regmap *map);
+ int (*read)(struct regmap *map, unsigned int reg, unsigned int *value);
+ int (*write)(struct regmap *map, unsigned int reg, unsigned int value);
+ int (*sync)(struct regmap *map);
};
bool regmap_writeable(struct regmap *map, unsigned int reg);
@@ -66,4 +101,21 @@ static inline void regmap_debugfs_init(struct regmap *map) { }
static inline void regmap_debugfs_exit(struct regmap *map) { }
#endif
+/* regcache core declarations */
+int regcache_init(struct regmap *map);
+void regcache_exit(struct regmap *map);
+int regcache_read(struct regmap *map,
+ unsigned int reg, unsigned int *value);
+int regcache_write(struct regmap *map,
+ unsigned int reg, unsigned int value);
+int regcache_sync(struct regmap *map);
+
+unsigned int regcache_get_val(const void *base, unsigned int idx,
+ unsigned int word_size);
+bool regcache_set_val(void *base, unsigned int idx,
+ unsigned int val, unsigned int word_size);
+int regcache_lookup_reg(struct regmap *map, unsigned int reg);
+int regcache_insert_reg(struct regmap *map, unsigned int reg,
+ unsigned int val);
+
#endif
diff --git a/drivers/base/regmap/regcache.c b/drivers/base/regmap/regcache.c
new file mode 100644
index 000000000000..9575e4c5f34a
--- /dev/null
+++ b/drivers/base/regmap/regcache.c
@@ -0,0 +1,304 @@
+/*
+ * Register cache access API
+ *
+ * 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 <trace/events/regmap.h>
+
+#include "internal.h"
+
+static const struct regcache_ops *cache_types[] = {
+};
+
+static int regcache_hw_init(struct regmap *map)
+{
+ int i, j;
+ int ret;
+ int count;
+ unsigned int val;
+ void *tmp_buf;
+
+ if (!map->num_reg_defaults_raw)
+ return -EINVAL;
+
+ if (!map->reg_defaults_raw) {
+ dev_warn(map->dev, "No cache defaults, reading back from HW\n");
+ tmp_buf = kmalloc(map->cache_size_raw, GFP_KERNEL);
+ if (!tmp_buf)
+ return -EINVAL;
+ ret = regmap_bulk_read(map, 0, tmp_buf,
+ map->num_reg_defaults_raw);
+ if (ret < 0) {
+ kfree(tmp_buf);
+ return ret;
+ }
+ map->reg_defaults_raw = tmp_buf;
+ map->cache_free = 1;
+ }
+
+ /* calculate the size of reg_defaults */
+ for (count = 0, i = 0; i < map->num_reg_defaults_raw; i++) {
+ val = regcache_get_val(map->reg_defaults_raw,
+ i, map->cache_word_size);
+ if (!val)
+ continue;
+ count++;
+ }
+
+ map->reg_defaults = kmalloc(count * sizeof(struct reg_default),
+ GFP_KERNEL);
+ if (!map->reg_defaults)
+ return -ENOMEM;
+
+ /* fill the reg_defaults */
+ map->num_reg_defaults = count;
+ for (i = 0, j = 0; i < map->num_reg_defaults_raw; i++) {
+ val = regcache_get_val(map->reg_defaults_raw,
+ i, map->cache_word_size);
+ if (!val)
+ continue;
+ map->reg_defaults[j].reg = i;
+ map->reg_defaults[j].def = val;
+ j++;
+ }
+
+ return 0;
+}
+
+int regcache_init(struct regmap *map)
+{
+ int ret;
+ int i;
+ void *tmp_buf;
+
+ if (map->cache_type == REGCACHE_NONE)
+ return 0;
+
+ for (i = 0; i < ARRAY_SIZE(cache_types); i++)
+ if (cache_types[i]->type == map->cache_type)
+ break;
+
+ if (i == ARRAY_SIZE(cache_types)) {
+ dev_err(map->dev, "Could not match compress type: %d\n",
+ map->cache_type);
+ return -EINVAL;
+ }
+
+ map->cache = NULL;
+ map->cache_ops = cache_types[i];
+
+ if (!map->cache_ops->read ||
+ !map->cache_ops->write ||
+ !map->cache_ops->name)
+ return -EINVAL;
+
+ /* We still need to ensure that the reg_defaults
+ * won't vanish from under us. We'll need to make
+ * a copy of it.
+ */
+ if (map->reg_defaults) {
+ if (!map->num_reg_defaults)
+ return -EINVAL;
+ tmp_buf = kmemdup(map->reg_defaults, map->num_reg_defaults *
+ sizeof(struct reg_default), GFP_KERNEL);
+ if (!tmp_buf)
+ return -ENOMEM;
+ map->reg_defaults = tmp_buf;
+ } else {
+ /* Some devices such as PMIC's don't have cache defaults,
+ * we cope with this by reading back the HW registers and
+ * crafting the cache defaults by hand.
+ */
+ ret = regcache_hw_init(map);
+ if (ret < 0)
+ return ret;
+ }
+
+ if (!map->max_register)
+ map->max_register = map->num_reg_defaults_raw;
+
+ if (map->cache_ops->init) {
+ dev_dbg(map->dev, "Initializing %s cache\n",
+ map->cache_ops->name);
+ return map->cache_ops->init(map);
+ }
+ return 0;
+}
+
+void regcache_exit(struct regmap *map)
+{
+ if (map->cache_type == REGCACHE_NONE)
+ return;
+
+ BUG_ON(!map->cache_ops);
+
+ kfree(map->reg_defaults);
+ if (map->cache_free)
+ kfree(map->reg_defaults_raw);
+
+ if (map->cache_ops->exit) {
+ dev_dbg(map->dev, "Destroying %s cache\n",
+ map->cache_ops->name);
+ map->cache_ops->exit(map);
+ }
+}
+
+/**
+ * regcache_read: Fetch the value of a given register from the cache.
+ *
+ * @map: map to configure.
+ * @reg: The register index.
+ * @value: The value to be returned.
+ *
+ * Return a negative value on failure, 0 on success.
+ */
+int regcache_read(struct regmap *map,
+ unsigned int reg, unsigned int *value)
+{
+ if (map->cache_type == REGCACHE_NONE)
+ return -ENOSYS;
+
+ BUG_ON(!map->cache_ops);
+
+ if (!regmap_readable(map, reg))
+ return -EIO;
+
+ if (!regmap_volatile(map, reg))
+ return map->cache_ops->read(map, reg, value);
+
+ return -EINVAL;
+}
+EXPORT_SYMBOL_GPL(regcache_read);
+
+/**
+ * regcache_write: Set the value of a given register in the cache.
+ *
+ * @map: map to configure.
+ * @reg: The register index.
+ * @value: The new register value.
+ *
+ * Return a negative value on failure, 0 on success.
+ */
+int regcache_write(struct regmap *map,
+ unsigned int reg, unsigned int value)
+{
+ if (map->cache_type == REGCACHE_NONE)
+ return 0;
+
+ BUG_ON(!map->cache_ops);
+
+ if (!regmap_writeable(map, reg))
+ return -EIO;
+
+ if (!regmap_volatile(map, reg))
+ return map->cache_ops->write(map, reg, value);
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(regcache_write);
+
+/**
+ * regcache_sync: Sync the register cache with the hardware.
+ *
+ * @map: map to configure.
+ *
+ * Any registers that should not be synced should be marked as
+ * volatile. In general drivers can choose not to use the provided
+ * syncing functionality if they so require.
+ *
+ * Return a negative value on failure, 0 on success.
+ */
+int regcache_sync(struct regmap *map)
+{
+ BUG_ON(!map->cache_ops);
+
+ if (map->cache_ops->sync) {
+ dev_dbg(map->dev, "Syncing %s cache\n",
+ map->cache_ops->name);
+ return map->cache_ops->sync(map);
+ }
+ return 0;
+}
+EXPORT_SYMBOL_GPL(regcache_sync);
+
+bool regcache_set_val(void *base, unsigned int idx,
+ unsigned int val, unsigned int word_size)
+{
+ switch (word_size) {
+ case 1: {
+ u8 *cache = base;
+ if (cache[idx] == val)
+ return true;
+ cache[idx] = val;
+ break;
+ }
+ case 2: {
+ u16 *cache = base;
+ if (cache[idx] == val)
+ return true;
+ cache[idx] = val;
+ break;
+ }
+ default:
+ BUG();
+ }
+ /* unreachable */
+ return false;
+}
+
+unsigned int regcache_get_val(const void *base, unsigned int idx,
+ unsigned int word_size)
+{
+ if (!base)
+ return -EINVAL;
+
+ switch (word_size) {
+ case 1: {
+ const u8 *cache = base;
+ return cache[idx];
+ }
+ case 2: {
+ const u16 *cache = base;
+ return cache[idx];
+ }
+ default:
+ BUG();
+ }
+ /* unreachable */
+ return -1;
+}
+
+int regcache_lookup_reg(struct regmap *map, unsigned int reg)
+{
+ unsigned int i;
+
+ for (i = 0; i < map->num_reg_defaults; i++)
+ if (map->reg_defaults[i].reg == reg)
+ return i;
+ return -1;
+}
+
+int regcache_insert_reg(struct regmap *map, unsigned int reg,
+ unsigned int val)
+{
+ void *tmp;
+
+ tmp = krealloc(map->reg_defaults,
+ (map->num_reg_defaults + 1) * sizeof(struct reg_default),
+ GFP_KERNEL);
+ if (!tmp)
+ return -ENOMEM;
+ map->reg_defaults = tmp;
+ map->num_reg_defaults++;
+ map->reg_defaults[map->num_reg_defaults - 1].reg = reg;
+ map->reg_defaults[map->num_reg_defaults - 1].def = val;
+ return 0;
+}
diff --git a/include/linux/regmap.h b/include/linux/regmap.h
index 18d4afaac166..9d8029449292 100644
--- a/include/linux/regmap.h
+++ b/include/linux/regmap.h
@@ -20,6 +20,11 @@
struct i2c_client;
struct spi_device;
+/* An enum of all the supported cache types */
+enum regcache_type {
+ REGCACHE_NONE,
+};
+
/**
* Default value for a register. We use an array of structs rather
* than a simple array as many modern devices have very sparse
@@ -59,6 +64,11 @@ struct reg_default {
* @write_flag_mask: Mask to be set in the top byte of the register when doing
* a write. If both read_flag_mask and write_flag_mask are
* empty the regmap_bus default masks are used.
+ *
+ * @cache_type: The actual cache type.
+ * @reg_defaults_raw: Power on reset values for registers (for use with
+ * register cache support).
+ * @num_reg_defaults_raw: Number of elements in reg_defaults_raw.
*/
struct regmap_config {
int reg_bits;
@@ -71,7 +81,10 @@ struct regmap_config {
unsigned int max_register;
struct reg_default *reg_defaults;
- int num_reg_defaults;
+ unsigned int num_reg_defaults;
+ enum regcache_type cache_type;
+ const void *reg_defaults_raw;
+ unsigned int num_reg_defaults_raw;
u8 read_flag_mask;
u8 write_flag_mask;
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-18 19:53:26 +0100