regmap: Updates for v3.11

A small but useful set of regmap updates this time around:
 
 - An abstraction for bitfields within a register map contributed by
   Srinivas Kandagatla, allowing drivers to cope more easily when
   hardware designers randomly move things about (mainly when talking
   to things like system controllers).
 
 - Changes from Lars-Peter Clausen to allow the MMIO regmap to be used from
   hard IRQ context.
 
 - Small improvements to the cache infrastructure and performance,
   including a default cache sync operation so now all regmaps can sync
   easily.
 
 There's also a pinctrl driver making use of the new bitfield API, merged
 here for dependency reasons.  There will be a simple add/add conflict
 with the pinctrl tree as a result.
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Merge tag 'regmap-v3.11' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regmap

Pull regmap updates from Mark Brown:
 "A small but useful set of regmap updates this time around:

   - An abstraction for bitfields within a register map contributed by
     Srinivas Kandagatla, allowing drivers to cope more easily when
     hardware designers randomly move things about (mainly when talking
     to things like system controllers).

   - Changes from Lars-Peter Clausen to allow the MMIO regmap to be used
     from hard IRQ context.

   - Small improvements to the cache infrastructure and performance,
     including a default cache sync operation so now all regmaps can
     sync easily.

  There's also a pinctrl driver making use of the new bitfield API,
  merged here for dependency reasons.  There will be a simple add/add
  conflict with the pinctrl tree as a result."

* tag 'regmap-v3.11' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regmap:
  pinctrl: st: Remove unnecessary use of of_match_ptr macro
  pinctrl: st: fix return value check
  pinctrl: st: Add pinctrl and pinconf support.
  regmap: debugfs: Suppress cache for partial register files
  regmap: Add regmap_field APIs
  regmap: core: Cache all registers by default when cache is enabled
  regmap: Implemented default cache sync operation
  regmap: Make regmap-mmio usable from atomic contexts
  regmap: regcache: Fixup locking for custom lock callbacks
  regmap: debugfs: Fix return from regmap_debugfs_get_dump_start
  regmap: debugfs: Don't mark lockdep as broken due to debugfs write
  regmap: rbtree: Use range information to allocate nodes
  regmap: rbtree: Factor out node allocation
  regmap: Make regmap_check_range_table() a public API
  regmap: Add support for discarding parts of the register cache

Documentation/devicetree/bindings/pinctrl/pinctrl-st.txt

@@ -0,0 +1,110 @@
+*ST pin controller.
+
+Each multi-function pin is controlled, driven and routed through the
+PIO multiplexing block. Each pin supports GPIO functionality (ALT0)
+and multiple alternate functions(ALT1 - ALTx) that directly connect
+the pin to different hardware blocks.
+
+When a pin is in GPIO mode, Output Enable (OE), Open Drain(OD), and
+Pull Up (PU) are driven by the related PIO block.
+
+ST pinctrl driver controls PIO multiplexing block and also interacts with
+gpio driver to configure a pin.
+
+Required properties: (PIO multiplexing block)
+- compatible	: should be "st,<SOC>-<pio-block>-pinctrl"
+	like st,stih415-sbc-pinctrl, st,stih415-front-pinctrl and so on.
+- gpio-controller : Indicates this device is a GPIO controller
+- #gpio-cells	  : Should be one. The first cell is the pin number.
+- st,retime-pin-mask	: Should be mask to specify which pins can be retimed.
+	If the property is not present, it is assumed that all the pins in the
+	bank are capable of retiming. Retiming is mainly used to improve the
+	IO timing margins of external synchronous interfaces.
+- st,bank-name		: Should be a name string for this bank as
+			specified in datasheet.
+- st,syscfg		: Should be a phandle of the syscfg node.
+
+Example:
+	pin-controller-sbc {
+		#address-cells	= <1>;
+		#size-cells	= <1>;
+		compatible	= "st,stih415-sbc-pinctrl";
+		st,syscfg	= <&syscfg_sbc>;
+		ranges 		= <0 0xfe610000 0x5000>;
+		PIO0: gpio@fe610000 {
+			gpio-controller;
+			#gpio-cells	= <1>;
+			reg		= <0 0x100>;
+			st,bank-name	= "PIO0";
+		};
+		...
+		pin-functions nodes follow...
+	};
+
+
+Contents of function subnode node:
+----------------------
+Required properties for pin configuration node:
+- st,pins	: Child node with list of pins with configuration.
+
+Below is the format of how each pin conf should look like.
+
+<bank offset mux mode rt_type rt_delay rt_clk>
+
+Every PIO is represented with 4-7 parameters depending on retime configuration.
+Each parameter is explained as below.
+
+-bank		: Should be bank phandle to which this PIO belongs.
+-offset		: Offset in the PIO bank.
+-mux		: Should be alternate function number associated this pin.
+		Use same numbers from datasheet.
+-mode		:pin configuration is selected from one of the below values.
+		IN
+		IN_PU
+		OUT
+		BIDIR
+		BIDIR_PU
+
+-rt_type	Retiming Configuration for the pin.
+		Possible retime configuration are:
+
+		-------		-------------
+		value		args
+		-------		-------------
+		NICLK		<delay> <clk>
+		ICLK_IO		<delay> <clk>
+		BYPASS		<delay>
+		DE_IO		<delay> <clk>
+		SE_ICLK_IO	<delay> <clk>
+		SE_NICLK_IO	<delay> <clk>
+
+- delay	is retime delay in pico seconds as mentioned in data sheet.
+
+- rt_clk	:clk to be use for retime.
+		Possible values are:
+		CLK_A
+		CLK_B
+		CLK_C
+		CLK_D
+
+Example of mmcclk pin which is a bi-direction pull pu with retime config
+as non inverted clock retimed with CLK_B and delay of 0 pico seconds:
+
+pin-controller {
+	...
+	mmc0 {
+		pinctrl_mmc: mmc {
+			st,pins {
+				mmcclk = <&PIO13 4 ALT4 BIDIR_PU NICLK 0 CLK_B>;
+				...
+			};
+		};
+	...
+	};
+};
+
+sdhci0:sdhci@fe810000{
+	...
+	pinctrl-names = "default";
+	pinctrl-0	= <&pinctrl_mmc>;
+};

drivers/base/regmap/internal.h

@@ -52,6 +52,7 @@ struct regmap_async {
 struct regmap {
 	struct mutex mutex;
 	spinlock_t spinlock;
+	unsigned long spinlock_flags;
 	regmap_lock lock;
 	regmap_unlock unlock;
 	void *lock_arg; /* This is passed to lock/unlock functions */
@@ -148,6 +149,7 @@ struct regcache_ops {
 	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, unsigned int min, unsigned int max);
+	int (*drop)(struct regmap *map, unsigned int min, unsigned int max);
 };
 
 bool regmap_writeable(struct regmap *map, unsigned int reg);
@@ -174,6 +176,14 @@ struct regmap_range_node {
 	unsigned int window_len;
 };
 
+struct regmap_field {
+	struct regmap *regmap;
+	unsigned int mask;
+	/* lsb */
+	unsigned int shift;
+	unsigned int reg;
+};
+
 #ifdef CONFIG_DEBUG_FS
 extern void regmap_debugfs_initcall(void);
 extern void regmap_debugfs_init(struct regmap *map, const char *name);

drivers/base/regmap/regcache-rbtree.c

@@ -304,6 +304,48 @@ static int regcache_rbtree_insert_to_block(struct regmap *map,
 	return 0;
 }
 
+static struct regcache_rbtree_node *
+regcache_rbtree_node_alloc(struct regmap *map, unsigned int reg)
+{
+	struct regcache_rbtree_node *rbnode;
+	const struct regmap_range *range;
+	int i;
+
+	rbnode = kzalloc(sizeof(*rbnode), GFP_KERNEL);
+	if (!rbnode)
+		return NULL;
+
+	/* If there is a read table then use it to guess at an allocation */
+	if (map->rd_table) {
+		for (i = 0; i < map->rd_table->n_yes_ranges; i++) {
+			if (regmap_reg_in_range(reg,
+						&map->rd_table->yes_ranges[i]))
+				break;
+		}
+
+		if (i != map->rd_table->n_yes_ranges) {
+			range = &map->rd_table->yes_ranges[i];
+			rbnode->blklen = range->range_max - range->range_min
+				+ 1;
+			rbnode->base_reg = range->range_min;
+		}
+	}
+
+	if (!rbnode->blklen) {
+		rbnode->blklen = sizeof(*rbnode);
+		rbnode->base_reg = reg;
+	}
+
+	rbnode->block = kmalloc(rbnode->blklen * map->cache_word_size,
+				GFP_KERNEL);
+	if (!rbnode->block) {
+		kfree(rbnode);
+		return NULL;
+	}
+
+	return rbnode;
+}
+
 static int regcache_rbtree_write(struct regmap *map, unsigned int reg,
 				 unsigned int value)
 {
@@ -354,23 +396,15 @@ static int regcache_rbtree_write(struct regmap *map, unsigned int reg,
 				return 0;
 			}
 		}
-		/* we did not manage to find a place to insert it in an existing
-		 * block so create a new rbnode with a single register in its block.
-		 * This block will get populated further if any other adjacent
-		 * registers get modified in the future.
+
+		/* We did not manage to find a place to insert it in
+		 * an existing block so create a new rbnode.
 		 */
-		rbnode = kzalloc(sizeof *rbnode, GFP_KERNEL);
+		rbnode = regcache_rbtree_node_alloc(map, reg);
 		if (!rbnode)
 			return -ENOMEM;
-		rbnode->blklen = sizeof(*rbnode);
-		rbnode->base_reg = reg;
-		rbnode->block = kmalloc(rbnode->blklen * map->cache_word_size,
-					GFP_KERNEL);
-		if (!rbnode->block) {
-			kfree(rbnode);
-			return -ENOMEM;
-		}
-		regcache_rbtree_set_register(map, rbnode, 0, value);
+		regcache_rbtree_set_register(map, rbnode,
+					     reg - rbnode->base_reg, value);
 		regcache_rbtree_insert(map, &rbtree_ctx->root, rbnode);
 		rbtree_ctx->cached_rbnode = rbnode;
 	}

drivers/base/regmap/regcache.c

@@ -250,6 +250,38 @@ int regcache_write(struct regmap *map,
 	return 0;
 }
 
+static int regcache_default_sync(struct regmap *map, unsigned int min,
+				 unsigned int max)
+{
+	unsigned int reg;
+
+	for (reg = min; reg <= max; reg++) {
+		unsigned int val;
+		int ret;
+
+		if (regmap_volatile(map, reg))
+			continue;
+
+		ret = regcache_read(map, reg, &val);
+		if (ret)
+			return ret;
+
+		/* Is this the hardware default?  If so skip. */
+		ret = regcache_lookup_reg(map, reg);
+		if (ret >= 0 && val == map->reg_defaults[ret].def)
+			continue;
+
+		map->cache_bypass = 1;
+		ret = _regmap_write(map, reg, val);
+		map->cache_bypass = 0;
+		if (ret)
+			return ret;
+		dev_dbg(map->dev, "Synced register %#x, value %#x\n", reg, val);
+	}
+
+	return 0;
+}
+
 /**
  * regcache_sync: Sync the register cache with the hardware.
  *
@@ -268,7 +300,7 @@ int regcache_sync(struct regmap *map)
 	const char *name;
 	unsigned int bypass;
 
-	BUG_ON(!map->cache_ops || !map->cache_ops->sync);
+	BUG_ON(!map->cache_ops);
 
 	map->lock(map->lock_arg);
 	/* Remember the initial bypass state */
@@ -297,7 +329,10 @@ int regcache_sync(struct regmap *map)
 	}
 	map->cache_bypass = 0;
 
-	ret = map->cache_ops->sync(map, 0, map->max_register);
+	if (map->cache_ops->sync)
+		ret = map->cache_ops->sync(map, 0, map->max_register);
+	else
+		ret = regcache_default_sync(map, 0, map->max_register);
 
 	if (ret == 0)
 		map->cache_dirty = false;
@@ -331,7 +366,7 @@ int regcache_sync_region(struct regmap *map, unsigned int min,
 	const char *name;
 	unsigned int bypass;
 
-	BUG_ON(!map->cache_ops || !map->cache_ops->sync);
+	BUG_ON(!map->cache_ops);
 
 	map->lock(map->lock_arg);
 
@@ -346,7 +381,10 @@ int regcache_sync_region(struct regmap *map, unsigned int min,
 	if (!map->cache_dirty)
 		goto out;
 
-	ret = map->cache_ops->sync(map, min, max);
+	if (map->cache_ops->sync)
+		ret = map->cache_ops->sync(map, min, max);
+	else
+		ret = regcache_default_sync(map, min, max);
 
 out:
 	trace_regcache_sync(map->dev, name, "stop region");
@@ -358,6 +396,43 @@ out:
 }
 EXPORT_SYMBOL_GPL(regcache_sync_region);
 
+/**
+ * regcache_drop_region: Discard part of the register cache
+ *
+ * @map: map to operate on
+ * @min: first register to discard
+ * @max: last register to discard
+ *
+ * Discard part of the register cache.
+ *
+ * Return a negative value on failure, 0 on success.
+ */
+int regcache_drop_region(struct regmap *map, unsigned int min,
+			 unsigned int max)
+{
+	unsigned int reg;
+	int ret = 0;
+
+	if (!map->cache_present && !(map->cache_ops && map->cache_ops->drop))
+		return -EINVAL;
+
+	map->lock(map->lock_arg);
+
+	trace_regcache_drop_region(map->dev, min, max);
+
+	if (map->cache_present)
+		for (reg = min; reg < max + 1; reg++)
+			clear_bit(reg, map->cache_present);
+
+	if (map->cache_ops && map->cache_ops->drop)
+		ret = map->cache_ops->drop(map, min, max);
+
+	map->unlock(map->lock_arg);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(regcache_drop_region);
+
 /**
  * regcache_cache_only: Put a register map into cache only mode
  *

drivers/base/regmap/regmap-debugfs.c

@@ -84,6 +84,10 @@ static unsigned int regmap_debugfs_get_dump_start(struct regmap *map,
 	unsigned int fpos_offset;
 	unsigned int reg_offset;
 
+	/* Suppress the cache if we're using a subrange */
+	if (from)
+		return from;
+
 	/*
 	 * If we don't have a cache build one so we don't have to do a
 	 * linear scan each time.
@@ -145,7 +149,7 @@ static unsigned int regmap_debugfs_get_dump_start(struct regmap *map,
 			reg_offset = fpos_offset / map->debugfs_tot_len;
 			*pos = c->min + (reg_offset * map->debugfs_tot_len);
 			mutex_unlock(&map->cache_lock);
-			return c->base_reg + reg_offset;
+			return c->base_reg + (reg_offset * map->reg_stride);
 		}
 
 		*pos = c->max;
@@ -281,7 +285,7 @@ static ssize_t regmap_map_write_file(struct file *file,
 		return -EINVAL;
 
 	/* Userspace has been fiddling around behind the kernel's back */
-	add_taint(TAINT_USER, LOCKDEP_NOW_UNRELIABLE);
+	add_taint(TAINT_USER, LOCKDEP_STILL_OK);
 
 	ret = regmap_write(map, reg, value);
 	if (ret < 0)

drivers/base/regmap/regmap.c

@@ -65,9 +65,8 @@ bool regmap_reg_in_ranges(unsigned int reg,
 }
 EXPORT_SYMBOL_GPL(regmap_reg_in_ranges);
 
-static bool _regmap_check_range_table(struct regmap *map,
-				      unsigned int reg,
-				      const struct regmap_access_table *table)
+bool regmap_check_range_table(struct regmap *map, unsigned int reg,
+			      const struct regmap_access_table *table)
 {
 	/* Check "no ranges" first */
 	if (regmap_reg_in_ranges(reg, table->no_ranges, table->n_no_ranges))
@@ -80,6 +79,7 @@ static bool _regmap_check_range_table(struct regmap *map,
 	return regmap_reg_in_ranges(reg, table->yes_ranges,
 				    table->n_yes_ranges);
 }
+EXPORT_SYMBOL_GPL(regmap_check_range_table);
 
 bool regmap_writeable(struct regmap *map, unsigned int reg)
 {
@@ -90,7 +90,7 @@ bool regmap_writeable(struct regmap *map, unsigned int reg)
 		return map->writeable_reg(map->dev, reg);
 
 	if (map->wr_table)
-		return _regmap_check_range_table(map, reg, map->wr_table);
+		return regmap_check_range_table(map, reg, map->wr_table);
 
 	return true;
 }
@@ -107,7 +107,7 @@ bool regmap_readable(struct regmap *map, unsigned int reg)
 		return map->readable_reg(map->dev, reg);
 
 	if (map->rd_table)
-		return _regmap_check_range_table(map, reg, map->rd_table);
+		return regmap_check_range_table(map, reg, map->rd_table);
 
 	return true;
 }
@@ -121,9 +121,12 @@ bool regmap_volatile(struct regmap *map, unsigned int reg)
 		return map->volatile_reg(map->dev, reg);
 
 	if (map->volatile_table)
-		return _regmap_check_range_table(map, reg, map->volatile_table);
+		return regmap_check_range_table(map, reg, map->volatile_table);
 
-	return true;
+	if (map->cache_ops)
+		return false;
+	else
+		return true;
 }
 
 bool regmap_precious(struct regmap *map, unsigned int reg)
@@ -135,7 +138,7 @@ bool regmap_precious(struct regmap *map, unsigned int reg)
 		return map->precious_reg(map->dev, reg);
 
 	if (map->precious_table)
-		return _regmap_check_range_table(map, reg, map->precious_table);
+		return regmap_check_range_table(map, reg, map->precious_table);
 
 	return false;
 }
@@ -302,13 +305,16 @@ static void regmap_unlock_mutex(void *__map)
 static void regmap_lock_spinlock(void *__map)
 {
 	struct regmap *map = __map;
-	spin_lock(&map->spinlock);
+	unsigned long flags;
+
+	spin_lock_irqsave(&map->spinlock, flags);
+	map->spinlock_flags = flags;
 }
 
 static void regmap_unlock_spinlock(void *__map)
 {
 	struct regmap *map = __map;
-	spin_unlock(&map->spinlock);
+	spin_unlock_irqrestore(&map->spinlock, map->spinlock_flags);
 }
 
 static void dev_get_regmap_release(struct device *dev, void *res)
@@ -801,6 +807,95 @@ struct regmap *devm_regmap_init(struct device *dev,
 }
 EXPORT_SYMBOL_GPL(devm_regmap_init);
 
+static void regmap_field_init(struct regmap_field *rm_field,
+	struct regmap *regmap, struct reg_field reg_field)
+{
+	int field_bits = reg_field.msb - reg_field.lsb + 1;
+	rm_field->regmap = regmap;
+	rm_field->reg = reg_field.reg;
+	rm_field->shift = reg_field.lsb;
+	rm_field->mask = ((BIT(field_bits) - 1) << reg_field.lsb);
+}
+
+/**
+ * devm_regmap_field_alloc(): Allocate and initialise a register field
+ * in a register map.
+ *
+ * @dev: Device that will be interacted with
+ * @regmap: regmap bank in which this register field is located.
+ * @reg_field: Register field with in the bank.
+ *
+ * The return value will be an ERR_PTR() on error or a valid pointer
+ * to a struct regmap_field. The regmap_field will be automatically freed
+ * by the device management code.
+ */
+struct regmap_field *devm_regmap_field_alloc(struct device *dev,
+		struct regmap *regmap, struct reg_field reg_field)
+{
+	struct regmap_field *rm_field = devm_kzalloc(dev,
+					sizeof(*rm_field), GFP_KERNEL);
+	if (!rm_field)
+		return ERR_PTR(-ENOMEM);
+
+	regmap_field_init(rm_field, regmap, reg_field);
+
+	return rm_field;
+
+}
+EXPORT_SYMBOL_GPL(devm_regmap_field_alloc);
+
+/**
+ * devm_regmap_field_free(): Free register field allocated using
+ * devm_regmap_field_alloc. Usally drivers need not call this function,
+ * as the memory allocated via devm will be freed as per device-driver
+ * life-cyle.
+ *
+ * @dev: Device that will be interacted with
+ * @field: regmap field which should be freed.
+ */
+void devm_regmap_field_free(struct device *dev,
+	struct regmap_field *field)
+{
+	devm_kfree(dev, field);
+}
+EXPORT_SYMBOL_GPL(devm_regmap_field_free);
+
+/**
+ * regmap_field_alloc(): Allocate and initialise a register field
+ * in a register map.
+ *
+ * @regmap: regmap bank in which this register field is located.
+ * @reg_field: Register field with in the bank.
+ *
+ * The return value will be an ERR_PTR() on error or a valid pointer
+ * to a struct regmap_field. The regmap_field should be freed by the
+ * user once its finished working with it using regmap_field_free().
+ */
+struct regmap_field *regmap_field_alloc(struct regmap *regmap,
+		struct reg_field reg_field)
+{
+	struct regmap_field *rm_field = kzalloc(sizeof(*rm_field), GFP_KERNEL);
+
+	if (!rm_field)
+		return ERR_PTR(-ENOMEM);
+
+	regmap_field_init(rm_field, regmap, reg_field);
+
+	return rm_field;
+}
+EXPORT_SYMBOL_GPL(regmap_field_alloc);
+
+/**
+ * regmap_field_free(): Free register field allocated using regmap_field_alloc
+ *
+ * @field: regmap field which should be freed.
+ */
+void regmap_field_free(struct regmap_field *field)
+{
+	kfree(field);
+}
+EXPORT_SYMBOL_GPL(regmap_field_free);
+
 /**
  * regmap_reinit_cache(): Reinitialise the current register cache
  *
@@ -1249,6 +1344,22 @@ int regmap_raw_write(struct regmap *map, unsigned int reg,
 }
 EXPORT_SYMBOL_GPL(regmap_raw_write);
 
+/**
+ * regmap_field_write(): Write a value to a single register field
+ *
+ * @field: Register field 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_field_write(struct regmap_field *field, unsigned int val)
+{
+	return regmap_update_bits(field->regmap, field->reg,
+				field->mask, val << field->shift);
+}
+EXPORT_SYMBOL_GPL(regmap_field_write);
+
 /*
  * regmap_bulk_write(): Write multiple registers to the device
  *
@@ -1531,6 +1642,31 @@ int regmap_raw_read(struct regmap *map, unsigned int reg, void *val,
 }
 EXPORT_SYMBOL_GPL(regmap_raw_read);
 
+/**
+ * regmap_field_read(): Read a value to a single register field
+ *
+ * @field: Register field to 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_field_read(struct regmap_field *field, unsigned int *val)
+{
+	int ret;
+	unsigned int reg_val;
+	ret = regmap_read(field->regmap, field->reg, &reg_val);
+	if (ret != 0)
+		return ret;
+
+	reg_val &= field->mask;
+	reg_val >>= field->shift;
+	*val = reg_val;
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(regmap_field_read);
+
 /**
  * regmap_bulk_read(): Read multiple registers from the device
  *

drivers/pinctrl/Kconfig

@@ -169,6 +169,12 @@ config PINCTRL_SUNXI
 	select PINMUX
 	select GENERIC_PINCONF
 
+config PINCTRL_ST
+	bool
+	depends on OF
+	select PINMUX
+	select PINCONF
+
 config PINCTRL_TEGRA
 	bool
 	select PINMUX

drivers/pinctrl/Makefile

@@ -46,6 +46,7 @@ obj-$(CONFIG_PINCTRL_S3C24XX)	+= pinctrl-s3c24xx.o
 obj-$(CONFIG_PINCTRL_S3C64XX)	+= pinctrl-s3c64xx.o
 obj-$(CONFIG_PINCTRL_XWAY)	+= pinctrl-xway.o
 obj-$(CONFIG_PINCTRL_LANTIQ)	+= pinctrl-lantiq.o
+obj-$(CONFIG_PINCTRL_ST) 	+= pinctrl-st.o
 
 obj-$(CONFIG_PLAT_ORION)        += mvebu/
 obj-$(CONFIG_ARCH_SHMOBILE)	+= sh-pfc/

include/linux/regmap.h

@@ -23,6 +23,7 @@ struct irq_domain;
 struct spi_device;
 struct regmap;
 struct regmap_range_cfg;
+struct regmap_field;
 
 /* An enum of all the supported cache types */
 enum regcache_type {
@@ -394,10 +395,15 @@ bool regmap_can_raw_write(struct regmap *map);
 int regcache_sync(struct regmap *map);
 int regcache_sync_region(struct regmap *map, unsigned int min,
 			 unsigned int max);
+int regcache_drop_region(struct regmap *map, unsigned int min,
+			 unsigned int max);
 void regcache_cache_only(struct regmap *map, bool enable);
 void regcache_cache_bypass(struct regmap *map, bool enable);
 void regcache_mark_dirty(struct regmap *map);
 
+bool regmap_check_range_table(struct regmap *map, unsigned int reg,
+			      const struct regmap_access_table *table);
+
 int regmap_register_patch(struct regmap *map, const struct reg_default *regs,
 			  int num_regs);
 
@@ -411,6 +417,36 @@ bool regmap_reg_in_ranges(unsigned int reg,
 			  const struct regmap_range *ranges,
 			  unsigned int nranges);
 
+/**
+ * Description of an register field
+ *
+ * @reg: Offset of the register within the regmap bank
+ * @lsb: lsb of the register field.
+ * @reg: msb of the register field.
+ */
+struct reg_field {
+	unsigned int reg;
+	unsigned int lsb;
+	unsigned int msb;
+};
+
+#define REG_FIELD(_reg, _lsb, _msb) {		\
+				.reg = _reg,	\
+				.lsb = _lsb,	\
+				.msb = _msb,	\
+				}
+
+struct regmap_field *regmap_field_alloc(struct regmap *regmap,
+		struct reg_field reg_field);
+void regmap_field_free(struct regmap_field *field);
+
+struct regmap_field *devm_regmap_field_alloc(struct device *dev,
+		struct regmap *regmap, struct reg_field reg_field);
+void devm_regmap_field_free(struct device *dev,	struct regmap_field *field);
+
+int regmap_field_read(struct regmap_field *field, unsigned int *val);
+int regmap_field_write(struct regmap_field *field, unsigned int val);
+
 /**
  * Description of an IRQ for the generic regmap irq_chip.
  *
@@ -562,6 +598,13 @@ static inline int regcache_sync_region(struct regmap *map, unsigned int min,
 	return -EINVAL;
 }
 
+static inline int regcache_drop_region(struct regmap *map, unsigned int min,
+				       unsigned int max)
+{
+	WARN_ONCE(1, "regmap API is disabled");
+	return -EINVAL;
+}
+
 static inline void regcache_cache_only(struct regmap *map, bool enable)
 {
 	WARN_ONCE(1, "regmap API is disabled");

include/trace/events/regmap.h

@@ -223,6 +223,29 @@ DEFINE_EVENT(regmap_async, regmap_async_complete_done,
 
 );
 
+TRACE_EVENT(regcache_drop_region,
+
+	TP_PROTO(struct device *dev, unsigned int from,
+		 unsigned int to),
+
+	TP_ARGS(dev, from, to),
+
+	TP_STRUCT__entry(
+		__string(       name,           dev_name(dev)   )
+		__field(	unsigned int,	from		)
+		__field(	unsigned int,	to		)
+	),
+
+	TP_fast_assign(
+		__assign_str(name, dev_name(dev));
+		__entry->from = from;
+		__entry->to = to;
+	),
+
+	TP_printk("%s %u-%u", __get_str(name), (unsigned int)__entry->from,
+		  (unsigned int)__entry->to)
+);
+
 #endif /* _TRACE_REGMAP_H */
 
 /* This part must be outside protection */