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Diffstat (limited to 'drivers/base/regmap/regmap.c')
-rw-r--r--drivers/base/regmap/regmap.c936
1 files changed, 936 insertions, 0 deletions
diff --git a/drivers/base/regmap/regmap.c b/drivers/base/regmap/regmap.c
new file mode 100644
index 00000000..bb80853f
--- /dev/null
+++ b/drivers/base/regmap/regmap.c
@@ -0,0 +1,936 @@
+/*
+ * Register map access API
+ *
+ * Copyright 2011 Wolfson Microelectronics plc
+ *
+ * Author: Mark Brown <broonie@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/device.h>
+#include <linux/slab.h>
+#include <linux/export.h>
+#include <linux/mutex.h>
+#include <linux/err.h>
+
+#define CREATE_TRACE_POINTS
+#include <trace/events/regmap.h>
+
+#include "internal.h"
+
+bool regmap_writeable(struct regmap *map, unsigned int reg)
+{
+ if (map->max_register && reg > map->max_register)
+ return false;
+
+ if (map->writeable_reg)
+ return map->writeable_reg(map->dev, reg);
+
+ return true;
+}
+
+bool regmap_readable(struct regmap *map, unsigned int reg)
+{
+ if (map->max_register && reg > map->max_register)
+ return false;
+
+ if (map->format.format_write)
+ return false;
+
+ if (map->readable_reg)
+ return map->readable_reg(map->dev, reg);
+
+ return true;
+}
+
+bool regmap_volatile(struct regmap *map, unsigned int reg)
+{
+ if (!regmap_readable(map, reg))
+ return false;
+
+ if (map->volatile_reg)
+ return map->volatile_reg(map->dev, reg);
+
+ return true;
+}
+
+bool regmap_precious(struct regmap *map, unsigned int reg)
+{
+ if (!regmap_readable(map, reg))
+ return false;
+
+ if (map->precious_reg)
+ return map->precious_reg(map->dev, reg);
+
+ return false;
+}
+
+static bool regmap_volatile_range(struct regmap *map, unsigned int reg,
+ unsigned int num)
+{
+ unsigned int i;
+
+ for (i = 0; i < num; i++)
+ if (!regmap_volatile(map, reg + i))
+ return false;
+
+ return true;
+}
+
+static void regmap_format_2_6_write(struct regmap *map,
+ unsigned int reg, unsigned int val)
+{
+ u8 *out = map->work_buf;
+
+ *out = (reg << 6) | val;
+}
+
+static void regmap_format_4_12_write(struct regmap *map,
+ unsigned int reg, unsigned int val)
+{
+ __be16 *out = map->work_buf;
+ *out = cpu_to_be16((reg << 12) | val);
+}
+
+static void regmap_format_7_9_write(struct regmap *map,
+ unsigned int reg, unsigned int val)
+{
+ __be16 *out = map->work_buf;
+ *out = cpu_to_be16((reg << 9) | val);
+}
+
+static void regmap_format_10_14_write(struct regmap *map,
+ unsigned int reg, unsigned int val)
+{
+ u8 *out = map->work_buf;
+
+ out[2] = val;
+ out[1] = (val >> 8) | (reg << 6);
+ out[0] = reg >> 2;
+}
+
+static void regmap_format_8(void *buf, unsigned int val)
+{
+ u8 *b = buf;
+
+ b[0] = val;
+}
+
+static void regmap_format_16(void *buf, unsigned int val)
+{
+ __be16 *b = buf;
+
+ b[0] = cpu_to_be16(val);
+}
+
+static void regmap_format_32(void *buf, unsigned int val)
+{
+ __be32 *b = buf;
+
+ b[0] = cpu_to_be32(val);
+}
+
+static unsigned int regmap_parse_8(void *buf)
+{
+ u8 *b = buf;
+
+ return b[0];
+}
+
+static unsigned int regmap_parse_16(void *buf)
+{
+ __be16 *b = buf;
+
+ b[0] = be16_to_cpu(b[0]);
+
+ return b[0];
+}
+
+static unsigned int regmap_parse_32(void *buf)
+{
+ __be32 *b = buf;
+
+ b[0] = be32_to_cpu(b[0]);
+
+ return b[0];
+}
+
+/**
+ * regmap_init(): Initialise register map
+ *
+ * @dev: Device that will be interacted with
+ * @bus: Bus-specific callbacks to use with device
+ * @config: Configuration for register map
+ *
+ * The return value will be an ERR_PTR() on error or a valid pointer to
+ * a struct regmap. This function should generally not be called
+ * directly, it should be called by bus-specific init functions.
+ */
+struct regmap *regmap_init(struct device *dev,
+ const struct regmap_bus *bus,
+ const struct regmap_config *config)
+{
+ struct regmap *map;
+ int ret = -EINVAL;
+
+ if (!bus || !config)
+ goto err;
+
+ map = kzalloc(sizeof(*map), GFP_KERNEL);
+ if (map == NULL) {
+ ret = -ENOMEM;
+ goto err;
+ }
+
+ mutex_init(&map->lock);
+ map->format.buf_size = (config->reg_bits + config->val_bits) / 8;
+ map->format.reg_bytes = DIV_ROUND_UP(config->reg_bits, 8);
+ map->format.pad_bytes = config->pad_bits / 8;
+ map->format.val_bytes = DIV_ROUND_UP(config->val_bits, 8);
+ map->format.buf_size += map->format.pad_bytes;
+ map->dev = dev;
+ map->bus = bus;
+ map->max_register = config->max_register;
+ map->writeable_reg = config->writeable_reg;
+ map->readable_reg = config->readable_reg;
+ map->volatile_reg = config->volatile_reg;
+ map->precious_reg = config->precious_reg;
+ map->cache_type = config->cache_type;
+
+ if (config->read_flag_mask || config->write_flag_mask) {
+ map->read_flag_mask = config->read_flag_mask;
+ map->write_flag_mask = config->write_flag_mask;
+ } else {
+ map->read_flag_mask = bus->read_flag_mask;
+ }
+
+ switch (config->reg_bits) {
+ case 2:
+ switch (config->val_bits) {
+ case 6:
+ map->format.format_write = regmap_format_2_6_write;
+ break;
+ default:
+ goto err_map;
+ }
+ break;
+
+ case 4:
+ switch (config->val_bits) {
+ case 12:
+ map->format.format_write = regmap_format_4_12_write;
+ break;
+ default:
+ goto err_map;
+ }
+ break;
+
+ case 7:
+ switch (config->val_bits) {
+ case 9:
+ map->format.format_write = regmap_format_7_9_write;
+ break;
+ default:
+ goto err_map;
+ }
+ break;
+
+ case 10:
+ switch (config->val_bits) {
+ case 14:
+ map->format.format_write = regmap_format_10_14_write;
+ break;
+ default:
+ goto err_map;
+ }
+ break;
+
+ case 8:
+ map->format.format_reg = regmap_format_8;
+ break;
+
+ case 16:
+ map->format.format_reg = regmap_format_16;
+ break;
+
+ case 32:
+ map->format.format_reg = regmap_format_32;
+ break;
+
+ default:
+ goto err_map;
+ }
+
+ switch (config->val_bits) {
+ case 8:
+ map->format.format_val = regmap_format_8;
+ map->format.parse_val = regmap_parse_8;
+ break;
+ case 16:
+ map->format.format_val = regmap_format_16;
+ map->format.parse_val = regmap_parse_16;
+ break;
+ case 32:
+ map->format.format_val = regmap_format_32;
+ map->format.parse_val = regmap_parse_32;
+ break;
+ }
+
+ if (!map->format.format_write &&
+ !(map->format.format_reg && map->format.format_val))
+ goto err_map;
+
+ map->work_buf = kzalloc(map->format.buf_size, GFP_KERNEL);
+ if (map->work_buf == NULL) {
+ ret = -ENOMEM;
+ goto err_map;
+ }
+
+ regmap_debugfs_init(map);
+
+ ret = regcache_init(map, config);
+ if (ret < 0)
+ goto err_free_workbuf;
+
+ return map;
+
+err_free_workbuf:
+ kfree(map->work_buf);
+err_map:
+ kfree(map);
+err:
+ return ERR_PTR(ret);
+}
+EXPORT_SYMBOL_GPL(regmap_init);
+
+static void devm_regmap_release(struct device *dev, void *res)
+{
+ regmap_exit(*(struct regmap **)res);
+}
+
+/**
+ * devm_regmap_init(): Initialise managed register map
+ *
+ * @dev: Device that will be interacted with
+ * @bus: Bus-specific callbacks to use with device
+ * @config: Configuration for register map
+ *
+ * The return value will be an ERR_PTR() on error or a valid pointer
+ * to a struct regmap. This function should generally not be called
+ * directly, it should be called by bus-specific init functions. The
+ * map will be automatically freed by the device management code.
+ */
+struct regmap *devm_regmap_init(struct device *dev,
+ const struct regmap_bus *bus,
+ const struct regmap_config *config)
+{
+ struct regmap **ptr, *regmap;
+
+ ptr = devres_alloc(devm_regmap_release, sizeof(*ptr), GFP_KERNEL);
+ if (!ptr)
+ return ERR_PTR(-ENOMEM);
+
+ regmap = regmap_init(dev, bus, config);
+ if (!IS_ERR(regmap)) {
+ *ptr = regmap;
+ devres_add(dev, ptr);
+ } else {
+ devres_free(ptr);
+ }
+
+ return regmap;
+}
+EXPORT_SYMBOL_GPL(devm_regmap_init);
+
+/**
+ * regmap_reinit_cache(): Reinitialise the current register cache
+ *
+ * @map: Register map to operate on.
+ * @config: New configuration. Only the cache data will be used.
+ *
+ * Discard any existing register cache for the map and initialize a
+ * new cache. This can be used to restore the cache to defaults or to
+ * update the cache configuration to reflect runtime discovery of the
+ * hardware.
+ */
+int regmap_reinit_cache(struct regmap *map, const struct regmap_config *config)
+{
+ int ret;
+
+ mutex_lock(&map->lock);
+
+ regcache_exit(map);
+ regmap_debugfs_exit(map);
+
+ map->max_register = config->max_register;
+ map->writeable_reg = config->writeable_reg;
+ map->readable_reg = config->readable_reg;
+ map->volatile_reg = config->volatile_reg;
+ map->precious_reg = config->precious_reg;
+ map->cache_type = config->cache_type;
+
+ regmap_debugfs_init(map);
+
+ map->cache_bypass = false;
+ map->cache_only = false;
+
+ ret = regcache_init(map, config);
+
+ mutex_unlock(&map->lock);
+
+ return ret;
+}
+
+/**
+ * regmap_exit(): Free a previously allocated register map
+ */
+void regmap_exit(struct regmap *map)
+{
+ regcache_exit(map);
+ regmap_debugfs_exit(map);
+ kfree(map->work_buf);
+ kfree(map);
+}
+EXPORT_SYMBOL_GPL(regmap_exit);
+
+static int _regmap_raw_write(struct regmap *map, unsigned int reg,
+ const void *val, size_t val_len)
+{
+ u8 *u8 = map->work_buf;
+ void *buf;
+ int ret = -ENOTSUPP;
+ size_t len;
+ int i;
+
+ /* Check for unwritable registers before we start */
+ if (map->writeable_reg)
+ for (i = 0; i < val_len / map->format.val_bytes; i++)
+ if (!map->writeable_reg(map->dev, reg + i))
+ return -EINVAL;
+
+ if (!map->cache_bypass && map->format.parse_val) {
+ unsigned int ival;
+ int val_bytes = map->format.val_bytes;
+ for (i = 0; i < val_len / val_bytes; i++) {
+ memcpy(map->work_buf, val + (i * val_bytes), val_bytes);
+ ival = map->format.parse_val(map->work_buf);
+ ret = regcache_write(map, reg + i, ival);
+ if (ret) {
+ dev_err(map->dev,
+ "Error in caching of register: %u ret: %d\n",
+ reg + i, ret);
+ return ret;
+ }
+ }
+ if (map->cache_only) {
+ map->cache_dirty = true;
+ return 0;
+ }
+ }
+
+ map->format.format_reg(map->work_buf, reg);
+
+ u8[0] |= map->write_flag_mask;
+
+ trace_regmap_hw_write_start(map->dev, reg,
+ val_len / map->format.val_bytes);
+
+ /* If we're doing a single register write we can probably just
+ * send the work_buf directly, otherwise try to do a gather
+ * write.
+ */
+ if (val == (map->work_buf + map->format.pad_bytes +
+ map->format.reg_bytes))
+ ret = map->bus->write(map->dev, map->work_buf,
+ map->format.reg_bytes +
+ map->format.pad_bytes +
+ val_len);
+ else if (map->bus->gather_write)
+ ret = map->bus->gather_write(map->dev, map->work_buf,
+ map->format.reg_bytes +
+ map->format.pad_bytes,
+ val, val_len);
+
+ /* If that didn't work fall back on linearising by hand. */
+ if (ret == -ENOTSUPP) {
+ len = map->format.reg_bytes + map->format.pad_bytes + val_len;
+ buf = kzalloc(len, GFP_KERNEL);
+ if (!buf)
+ return -ENOMEM;
+
+ memcpy(buf, map->work_buf, map->format.reg_bytes);
+ memcpy(buf + map->format.reg_bytes + map->format.pad_bytes,
+ val, val_len);
+ ret = map->bus->write(map->dev, buf, len);
+
+ kfree(buf);
+ }
+
+ trace_regmap_hw_write_done(map->dev, reg,
+ val_len / map->format.val_bytes);
+
+ return ret;
+}
+
+int _regmap_write(struct regmap *map, unsigned int reg,
+ unsigned int val)
+{
+ int ret;
+ BUG_ON(!map->format.format_write && !map->format.format_val);
+
+ if (!map->cache_bypass && map->format.format_write) {
+ ret = regcache_write(map, reg, val);
+ if (ret != 0)
+ return ret;
+ if (map->cache_only) {
+ map->cache_dirty = true;
+ return 0;
+ }
+ }
+
+ trace_regmap_reg_write(map->dev, reg, val);
+
+ if (map->format.format_write) {
+ map->format.format_write(map, reg, val);
+
+ trace_regmap_hw_write_start(map->dev, reg, 1);
+
+ ret = map->bus->write(map->dev, map->work_buf,
+ map->format.buf_size);
+
+ trace_regmap_hw_write_done(map->dev, reg, 1);
+
+ return ret;
+ } else {
+ map->format.format_val(map->work_buf + map->format.reg_bytes
+ + map->format.pad_bytes, val);
+ return _regmap_raw_write(map, reg,
+ map->work_buf +
+ map->format.reg_bytes +
+ map->format.pad_bytes,
+ map->format.val_bytes);
+ }
+}
+
+/**
+ * regmap_write(): Write a value to a single register
+ *
+ * @map: Register map to write to
+ * @reg: Register to write to
+ * @val: Value to be written
+ *
+ * A value of zero will be returned on success, a negative errno will
+ * be returned in error cases.
+ */
+int regmap_write(struct regmap *map, unsigned int reg, unsigned int val)
+{
+ int ret;
+
+ mutex_lock(&map->lock);
+
+ ret = _regmap_write(map, reg, val);
+
+ mutex_unlock(&map->lock);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(regmap_write);
+
+/**
+ * regmap_raw_write(): Write raw values to one or more registers
+ *
+ * @map: Register map to write to
+ * @reg: Initial register to write to
+ * @val: Block of data to be written, laid out for direct transmission to the
+ * device
+ * @val_len: Length of data pointed to by val.
+ *
+ * This function is intended to be used for things like firmware
+ * download where a large block of data needs to be transferred to the
+ * device. No formatting will be done on the data provided.
+ *
+ * A value of zero will be returned on success, a negative errno will
+ * be returned in error cases.
+ */
+int regmap_raw_write(struct regmap *map, unsigned int reg,
+ const void *val, size_t val_len)
+{
+ int ret;
+
+ mutex_lock(&map->lock);
+
+ ret = _regmap_raw_write(map, reg, val, val_len);
+
+ mutex_unlock(&map->lock);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(regmap_raw_write);
+
+/*
+ * regmap_bulk_write(): Write multiple registers to the device
+ *
+ * @map: Register map to write to
+ * @reg: First register to be write from
+ * @val: Block of data to be written, in native register size for device
+ * @val_count: Number of registers to write
+ *
+ * This function is intended to be used for writing a large block of
+ * data to be device either in single transfer or multiple transfer.
+ *
+ * A value of zero will be returned on success, a negative errno will
+ * be returned in error cases.
+ */
+int regmap_bulk_write(struct regmap *map, unsigned int reg, const void *val,
+ size_t val_count)
+{
+ int ret = 0, i;
+ size_t val_bytes = map->format.val_bytes;
+ void *wval;
+
+ if (!map->format.parse_val)
+ return -EINVAL;
+
+ mutex_lock(&map->lock);
+
+ /* No formatting is require if val_byte is 1 */
+ if (val_bytes == 1) {
+ wval = (void *)val;
+ } else {
+ wval = kmemdup(val, val_count * val_bytes, GFP_KERNEL);
+ if (!wval) {
+ ret = -ENOMEM;
+ dev_err(map->dev, "Error in memory allocation\n");
+ goto out;
+ }
+ for (i = 0; i < val_count * val_bytes; i += val_bytes)
+ map->format.parse_val(wval + i);
+ }
+ ret = _regmap_raw_write(map, reg, wval, val_bytes * val_count);
+
+ if (val_bytes != 1)
+ kfree(wval);
+
+out:
+ mutex_unlock(&map->lock);
+ return ret;
+}
+EXPORT_SYMBOL_GPL(regmap_bulk_write);
+
+static int _regmap_raw_read(struct regmap *map, unsigned int reg, void *val,
+ unsigned int val_len)
+{
+ u8 *u8 = map->work_buf;
+ int ret;
+
+ map->format.format_reg(map->work_buf, reg);
+
+ /*
+ * Some buses or devices flag reads by setting the high bits in the
+ * register addresss; since it's always the high bits for all
+ * current formats we can do this here rather than in
+ * formatting. This may break if we get interesting formats.
+ */
+ u8[0] |= map->read_flag_mask;
+
+ trace_regmap_hw_read_start(map->dev, reg,
+ val_len / map->format.val_bytes);
+
+ ret = map->bus->read(map->dev, map->work_buf,
+ map->format.reg_bytes + map->format.pad_bytes,
+ val, val_len);
+
+ trace_regmap_hw_read_done(map->dev, reg,
+ val_len / map->format.val_bytes);
+
+ return ret;
+}
+
+static int _regmap_read(struct regmap *map, unsigned int reg,
+ unsigned int *val)
+{
+ int ret;
+
+ if (!map->cache_bypass) {
+ ret = regcache_read(map, reg, val);
+ if (ret == 0)
+ return 0;
+ }
+
+ if (!map->format.parse_val)
+ return -EINVAL;
+
+ if (map->cache_only)
+ return -EBUSY;
+
+ ret = _regmap_raw_read(map, reg, map->work_buf, map->format.val_bytes);
+ if (ret == 0) {
+ *val = map->format.parse_val(map->work_buf);
+ trace_regmap_reg_read(map->dev, reg, *val);
+ }
+
+ return ret;
+}
+
+/**
+ * regmap_read(): Read a value from a single register
+ *
+ * @map: Register map to write to
+ * @reg: Register to be read from
+ * @val: Pointer to store read value
+ *
+ * A value of zero will be returned on success, a negative errno will
+ * be returned in error cases.
+ */
+int regmap_read(struct regmap *map, unsigned int reg, unsigned int *val)
+{
+ int ret;
+
+ mutex_lock(&map->lock);
+
+ ret = _regmap_read(map, reg, val);
+
+ mutex_unlock(&map->lock);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(regmap_read);
+
+/**
+ * regmap_raw_read(): Read raw data from the device
+ *
+ * @map: Register map to write to
+ * @reg: First register to be read from
+ * @val: Pointer to store read value
+ * @val_len: Size of data to read
+ *
+ * A value of zero will be returned on success, a negative errno will
+ * be returned in error cases.
+ */
+int regmap_raw_read(struct regmap *map, unsigned int reg, void *val,
+ size_t val_len)
+{
+ size_t val_bytes = map->format.val_bytes;
+ size_t val_count = val_len / val_bytes;
+ unsigned int v;
+ int ret, i;
+
+ mutex_lock(&map->lock);
+
+ if (regmap_volatile_range(map, reg, val_count) || map->cache_bypass ||
+ map->cache_type == REGCACHE_NONE) {
+ /* Physical block read if there's no cache involved */
+ ret = _regmap_raw_read(map, reg, val, val_len);
+
+ } else {
+ /* Otherwise go word by word for the cache; should be low
+ * cost as we expect to hit the cache.
+ */
+ for (i = 0; i < val_count; i++) {
+ ret = _regmap_read(map, reg + i, &v);
+ if (ret != 0)
+ goto out;
+
+ map->format.format_val(val + (i * val_bytes), v);
+ }
+ }
+
+ out:
+ mutex_unlock(&map->lock);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(regmap_raw_read);
+
+/**
+ * regmap_bulk_read(): Read multiple registers from the device
+ *
+ * @map: Register map to write to
+ * @reg: First register to be read from
+ * @val: Pointer to store read value, in native register size for device
+ * @val_count: Number of registers to read
+ *
+ * A value of zero will be returned on success, a negative errno will
+ * be returned in error cases.
+ */
+int regmap_bulk_read(struct regmap *map, unsigned int reg, void *val,
+ size_t val_count)
+{
+ int ret, i;
+ size_t val_bytes = map->format.val_bytes;
+ bool vol = regmap_volatile_range(map, reg, val_count);
+
+ if (!map->format.parse_val)
+ return -EINVAL;
+
+ if (vol || map->cache_type == REGCACHE_NONE) {
+ ret = regmap_raw_read(map, reg, val, val_bytes * val_count);
+ if (ret != 0)
+ return ret;
+
+ for (i = 0; i < val_count * val_bytes; i += val_bytes)
+ map->format.parse_val(val + i);
+ } else {
+ for (i = 0; i < val_count; i++) {
+ unsigned int ival;
+ ret = regmap_read(map, reg + i, &ival);
+ if (ret != 0)
+ return ret;
+ memcpy(val + (i * val_bytes), &ival, val_bytes);
+ }
+ }
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(regmap_bulk_read);
+
+static int _regmap_update_bits(struct regmap *map, unsigned int reg,
+ unsigned int mask, unsigned int val,
+ bool *change)
+{
+ int ret;
+ unsigned int tmp, orig;
+
+ mutex_lock(&map->lock);
+
+ ret = _regmap_read(map, reg, &orig);
+ if (ret != 0)
+ goto out;
+
+ tmp = orig & ~mask;
+ tmp |= val & mask;
+
+ if (tmp != orig) {
+ ret = _regmap_write(map, reg, tmp);
+ *change = true;
+ } else {
+ *change = false;
+ }
+
+out:
+ mutex_unlock(&map->lock);
+
+ return ret;
+}
+
+/**
+ * regmap_update_bits: Perform a read/modify/write cycle on the register map
+ *
+ * @map: Register map to update
+ * @reg: Register to update
+ * @mask: Bitmask to change
+ * @val: New value for bitmask
+ *
+ * Returns zero for success, a negative number on error.
+ */
+int regmap_update_bits(struct regmap *map, unsigned int reg,
+ unsigned int mask, unsigned int val)
+{
+ bool change;
+ return _regmap_update_bits(map, reg, mask, val, &change);
+}
+EXPORT_SYMBOL_GPL(regmap_update_bits);
+
+/**
+ * regmap_update_bits_check: Perform a read/modify/write cycle on the
+ * register map and report if updated
+ *
+ * @map: Register map to update
+ * @reg: Register to update
+ * @mask: Bitmask to change
+ * @val: New value for bitmask
+ * @change: Boolean indicating if a write was done
+ *
+ * Returns zero for success, a negative number on error.
+ */
+int regmap_update_bits_check(struct regmap *map, unsigned int reg,
+ unsigned int mask, unsigned int val,
+ bool *change)
+{
+ return _regmap_update_bits(map, reg, mask, val, change);
+}
+EXPORT_SYMBOL_GPL(regmap_update_bits_check);
+
+/**
+ * regmap_register_patch: Register and apply register updates to be applied
+ * on device initialistion
+ *
+ * @map: Register map to apply updates to.
+ * @regs: Values to update.
+ * @num_regs: Number of entries in regs.
+ *
+ * Register a set of register updates to be applied to the device
+ * whenever the device registers are synchronised with the cache and
+ * apply them immediately. Typically this is used to apply
+ * corrections to be applied to the device defaults on startup, such
+ * as the updates some vendors provide to undocumented registers.
+ */
+int regmap_register_patch(struct regmap *map, const struct reg_default *regs,
+ int num_regs)
+{
+ int i, ret;
+ bool bypass;
+
+ /* If needed the implementation can be extended to support this */
+ if (map->patch)
+ return -EBUSY;
+
+ mutex_lock(&map->lock);
+
+ bypass = map->cache_bypass;
+
+ map->cache_bypass = true;
+
+ /* Write out first; it's useful to apply even if we fail later. */
+ for (i = 0; i < num_regs; i++) {
+ ret = _regmap_write(map, regs[i].reg, regs[i].def);
+ if (ret != 0) {
+ dev_err(map->dev, "Failed to write %x = %x: %d\n",
+ regs[i].reg, regs[i].def, ret);
+ goto out;
+ }
+ }
+
+ map->patch = kcalloc(num_regs, sizeof(struct reg_default), GFP_KERNEL);
+ if (map->patch != NULL) {
+ memcpy(map->patch, regs,
+ num_regs * sizeof(struct reg_default));
+ map->patch_regs = num_regs;
+ } else {
+ ret = -ENOMEM;
+ }
+
+out:
+ map->cache_bypass = bypass;
+
+ mutex_unlock(&map->lock);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(regmap_register_patch);
+
+/*
+ * regmap_get_val_bytes(): Report the size of a register value
+ *
+ * Report the size of a register value, mainly intended to for use by
+ * generic infrastructure built on top of regmap.
+ */
+int regmap_get_val_bytes(struct regmap *map)
+{
+ if (map->format.format_write)
+ return -EINVAL;
+
+ return map->format.val_bytes;
+}
+EXPORT_SYMBOL_GPL(regmap_get_val_bytes);
+
+static int __init regmap_initcall(void)
+{
+ regmap_debugfs_initcall();
+
+ return 0;
+}
+postcore_initcall(regmap_initcall);
generated by cgit (git 2.34.1) at 2024-12-20 12:40:51 +0000