Merge tag 'regmap-v4.19' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regmap

Pull regmap updates from Mark Brown:
 "Several small new features for regmap this time around:

   - Support for SCCB, an I2C variant used on some media cards. This has
     also pulled in an I2C commit from Peter Rosin as a dependency.

   - Addition of an API for reading repeatedly from registers where the
     address doesn't automatically increment like some ADC outputs or
     GPIO status registers.

   - Support for bulk I/O on Slimbus"

* tag 'regmap-v4.19' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regmap:
  regmap: Add regmap_noinc_read API
  regmap: sccb: fix typo and sort headers alphabetically
  i2c: smbus: add unlocked __i2c_smbus_xfer variant
  regmap: add SCCB support
  regmap: slimbus: add support to multi read/write

6 files changed, 221 insertions, 17 deletions

diff --git a/drivers/base/regmap/Kconfig b/drivers/base/regmap/Kconfig
index aff34c0c2a3e..6ad5ef48b61e 100644
--- a/drivers/base/regmap/Kconfig
+++ b/drivers/base/regmap/Kconfig
@@ -45,3 +45,7 @@ config REGMAP_IRQ
 config REGMAP_SOUNDWIRE
 	tristate
 	depends on SOUNDWIRE_BUS
+
+config REGMAP_SCCB
+	tristate
+	depends on I2C
diff --git a/drivers/base/regmap/Makefile b/drivers/base/regmap/Makefile
index 5ed0023fabda..f5b4e8851d00 100644
--- a/drivers/base/regmap/Makefile
+++ b/drivers/base/regmap/Makefile
@@ -15,3 +15,4 @@ obj-$(CONFIG_REGMAP_MMIO) += regmap-mmio.o
 obj-$(CONFIG_REGMAP_IRQ) += regmap-irq.o
 obj-$(CONFIG_REGMAP_W1) += regmap-w1.o
 obj-$(CONFIG_REGMAP_SOUNDWIRE) += regmap-sdw.o
+obj-$(CONFIG_REGMAP_SCCB) += regmap-sccb.o
diff --git a/drivers/base/regmap/internal.h b/drivers/base/regmap/internal.h
index 53785e0e297a..a6bf34d6394e 100644
--- a/drivers/base/regmap/internal.h
+++ b/drivers/base/regmap/internal.h
@@ -94,10 +94,12 @@ struct regmap {
 	bool (*readable_reg)(struct device *dev, unsigned int reg);
 	bool (*volatile_reg)(struct device *dev, unsigned int reg);
 	bool (*precious_reg)(struct device *dev, unsigned int reg);
+	bool (*readable_noinc_reg)(struct device *dev, unsigned int reg);
 	const struct regmap_access_table *wr_table;
 	const struct regmap_access_table *rd_table;
 	const struct regmap_access_table *volatile_table;
 	const struct regmap_access_table *precious_table;
+	const struct regmap_access_table *rd_noinc_table;
 
 	int (*reg_read)(void *context, unsigned int reg, unsigned int *val);
 	int (*reg_write)(void *context, unsigned int reg, unsigned int val);
@@ -181,6 +183,7 @@ bool regmap_writeable(struct regmap *map, unsigned int reg);
 bool regmap_readable(struct regmap *map, unsigned int reg);
 bool regmap_volatile(struct regmap *map, unsigned int reg);
 bool regmap_precious(struct regmap *map, unsigned int reg);
+bool regmap_readable_noinc(struct regmap *map, unsigned int reg);
 
 int _regmap_write(struct regmap *map, unsigned int reg,
 		  unsigned int val);
diff --git a/drivers/base/regmap/regmap-sccb.c b/drivers/base/regmap/regmap-sccb.c
new file mode 100644
index 000000000000..597042e2d009
--- /dev/null
+++ b/drivers/base/regmap/regmap-sccb.c
@@ -0,0 +1,128 @@
+// SPDX-License-Identifier: GPL-2.0
+// Register map access API - SCCB support
+
+#include <linux/i2c.h>
+#include <linux/module.h>
+#include <linux/regmap.h>
+
+#include "internal.h"
+
+/**
+ * sccb_is_available - Check if the adapter supports SCCB protocol
+ * @adap: I2C adapter
+ *
+ * Return true if the I2C adapter is capable of using SCCB helper functions,
+ * false otherwise.
+ */
+static bool sccb_is_available(struct i2c_adapter *adap)
+{
+	u32 needed_funcs = I2C_FUNC_SMBUS_BYTE | I2C_FUNC_SMBUS_WRITE_BYTE_DATA;
+
+	/*
+	 * If we ever want support for hardware doing SCCB natively, we will
+	 * introduce a sccb_xfer() callback to struct i2c_algorithm and check
+	 * for it here.
+	 */
+
+	return (i2c_get_functionality(adap) & needed_funcs) == needed_funcs;
+}
+
+/**
+ * regmap_sccb_read - Read data from SCCB slave device
+ * @context: Device that will be interacted with
+ * @reg: Register to be read from
+ * @val: Pointer to store read value
+ *
+ * This executes the 2-phase write transmission cycle that is followed by a
+ * 2-phase read transmission cycle, returning negative errno else zero on
+ * success.
+ */
+static int regmap_sccb_read(void *context, unsigned int reg, unsigned int *val)
+{
+	struct device *dev = context;
+	struct i2c_client *i2c = to_i2c_client(dev);
+	int ret;
+	union i2c_smbus_data data;
+
+	i2c_lock_bus(i2c->adapter, I2C_LOCK_SEGMENT);
+
+	ret = __i2c_smbus_xfer(i2c->adapter, i2c->addr, i2c->flags,
+			       I2C_SMBUS_WRITE, reg, I2C_SMBUS_BYTE, NULL);
+	if (ret < 0)
+		goto out;
+
+	ret = __i2c_smbus_xfer(i2c->adapter, i2c->addr, i2c->flags,
+			       I2C_SMBUS_READ, 0, I2C_SMBUS_BYTE, &data);
+	if (ret < 0)
+		goto out;
+
+	*val = data.byte;
+out:
+	i2c_unlock_bus(i2c->adapter, I2C_LOCK_SEGMENT);
+
+	return ret;
+}
+
+/**
+ * regmap_sccb_write - Write data to SCCB slave device
+ * @context: Device that will be interacted with
+ * @reg: Register to write to
+ * @val: Value to be written
+ *
+ * This executes the SCCB 3-phase write transmission cycle, returning negative
+ * errno else zero on success.
+ */
+static int regmap_sccb_write(void *context, unsigned int reg, unsigned int val)
+{
+	struct device *dev = context;
+	struct i2c_client *i2c = to_i2c_client(dev);
+
+	return i2c_smbus_write_byte_data(i2c, reg, val);
+}
+
+static struct regmap_bus regmap_sccb_bus = {
+	.reg_write = regmap_sccb_write,
+	.reg_read = regmap_sccb_read,
+};
+
+static const struct regmap_bus *regmap_get_sccb_bus(struct i2c_client *i2c,
+					const struct regmap_config *config)
+{
+	if (config->val_bits == 8 && config->reg_bits == 8 &&
+			sccb_is_available(i2c->adapter))
+		return &regmap_sccb_bus;
+
+	return ERR_PTR(-ENOTSUPP);
+}
+
+struct regmap *__regmap_init_sccb(struct i2c_client *i2c,
+				  const struct regmap_config *config,
+				  struct lock_class_key *lock_key,
+				  const char *lock_name)
+{
+	const struct regmap_bus *bus = regmap_get_sccb_bus(i2c, config);
+
+	if (IS_ERR(bus))
+		return ERR_CAST(bus);
+
+	return __regmap_init(&i2c->dev, bus, &i2c->dev, config,
+			     lock_key, lock_name);
+}
+EXPORT_SYMBOL_GPL(__regmap_init_sccb);
+
+struct regmap *__devm_regmap_init_sccb(struct i2c_client *i2c,
+				       const struct regmap_config *config,
+				       struct lock_class_key *lock_key,
+				       const char *lock_name)
+{
+	const struct regmap_bus *bus = regmap_get_sccb_bus(i2c, config);
+
+	if (IS_ERR(bus))
+		return ERR_CAST(bus);
+
+	return __devm_regmap_init(&i2c->dev, bus, &i2c->dev, config,
+				  lock_key, lock_name);
+}
+EXPORT_SYMBOL_GPL(__devm_regmap_init_sccb);
+
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/base/regmap/regmap-slimbus.c b/drivers/base/regmap/regmap-slimbus.c
index 91d501eda8a9..0968059f1ef5 100644
--- a/drivers/base/regmap/regmap-slimbus.c
+++ b/drivers/base/regmap/regmap-slimbus.c
@@ -7,33 +7,24 @@
 
 #include "internal.h"
 
-static int regmap_slimbus_byte_reg_read(void *context, unsigned int reg,
-					unsigned int *val)
+static int regmap_slimbus_write(void *context, const void *data, size_t count)
 {
 	struct slim_device *sdev = context;
-	int v;
 
-	v = slim_readb(sdev, reg);
-
-	if (v < 0)
-		return v;
-
-	*val = v;
-
-	return 0;
+	return slim_write(sdev, *(u16 *)data, count - 2, (u8 *)data + 2);
 }
 
-static int regmap_slimbus_byte_reg_write(void *context, unsigned int reg,
-					 unsigned int val)
+static int regmap_slimbus_read(void *context, const void *reg, size_t reg_size,
+			       void *val, size_t val_size)
 {
 	struct slim_device *sdev = context;
 
-	return slim_writeb(sdev, reg, val);
+	return slim_read(sdev, *(u16 *)reg, val_size, val);
 }
 
 static struct regmap_bus regmap_slimbus_bus = {
-	.reg_write = regmap_slimbus_byte_reg_write,
-	.reg_read = regmap_slimbus_byte_reg_read,
+	.write = regmap_slimbus_write,
+	.read = regmap_slimbus_read,
 	.reg_format_endian_default = REGMAP_ENDIAN_LITTLE,
 	.val_format_endian_default = REGMAP_ENDIAN_LITTLE,
 };
diff --git a/drivers/base/regmap/regmap.c b/drivers/base/regmap/regmap.c
index 3bc84885eb91..0360a90ad6b6 100644
--- a/drivers/base/regmap/regmap.c
+++ b/drivers/base/regmap/regmap.c
@@ -168,6 +168,17 @@ bool regmap_precious(struct regmap *map, unsigned int reg)
 	return false;
 }
 
+bool regmap_readable_noinc(struct regmap *map, unsigned int reg)
+{
+	if (map->readable_noinc_reg)
+		return map->readable_noinc_reg(map->dev, reg);
+
+	if (map->rd_noinc_table)
+		return regmap_check_range_table(map, reg, map->rd_noinc_table);
+
+	return true;
+}
+
 static bool regmap_volatile_range(struct regmap *map, unsigned int reg,
 	size_t num)
 {
@@ -766,10 +777,12 @@ struct regmap *__regmap_init(struct device *dev,
 	map->rd_table = config->rd_table;
 	map->volatile_table = config->volatile_table;
 	map->precious_table = config->precious_table;
+	map->rd_noinc_table = config->rd_noinc_table;
 	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->readable_noinc_reg = config->readable_noinc_reg;
 	map->cache_type = config->cache_type;
 
 	spin_lock_init(&map->async_lock);
@@ -1285,6 +1298,7 @@ int regmap_reinit_cache(struct regmap *map, const struct regmap_config *config)
 	map->readable_reg = config->readable_reg;
 	map->volatile_reg = config->volatile_reg;
 	map->precious_reg = config->precious_reg;
+	map->readable_noinc_reg = config->readable_noinc_reg;
 	map->cache_type = config->cache_type;
 
 	regmap_debugfs_init(map, config->name);
@@ -2564,7 +2578,70 @@ 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
+ * regmap_noinc_read(): Read data from a register without incrementing the
+ *			register number
+ *
+ * @map: Register map to read from
+ * @reg: Register to read from
+ * @val: Pointer to data buffer
+ * @val_len: Length of output buffer in bytes.
+ *
+ * The regmap API usually assumes that bulk bus read operations will read a
+ * range of registers. Some devices have certain registers for which a read
+ * operation read will read from an internal FIFO.
+ *
+ * The target register must be volatile but registers after it can be
+ * completely unrelated cacheable registers.
+ *
+ * This will attempt multiple reads as required to read val_len bytes.
+ *
+ * A value of zero will be returned on success, a negative errno will be
+ * returned in error cases.
+ */
+int regmap_noinc_read(struct regmap *map, unsigned int reg,
+		      void *val, size_t val_len)
+{
+	size_t read_len;
+	int ret;
+
+	if (!map->bus)
+		return -EINVAL;
+	if (!map->bus->read)
+		return -ENOTSUPP;
+	if (val_len % map->format.val_bytes)
+		return -EINVAL;
+	if (!IS_ALIGNED(reg, map->reg_stride))
+		return -EINVAL;
+	if (val_len == 0)
+		return -EINVAL;
+
+	map->lock(map->lock_arg);
+
+	if (!regmap_volatile(map, reg) || !regmap_readable_noinc(map, reg)) {
+		ret = -EINVAL;
+		goto out_unlock;
+	}
+
+	while (val_len) {
+		if (map->max_raw_read && map->max_raw_read < val_len)
+			read_len = map->max_raw_read;
+		else
+			read_len = val_len;
+		ret = _regmap_raw_read(map, reg, val, read_len);
+		if (ret)
+			goto out_unlock;
+		val = ((u8 *)val) + read_len;
+		val_len -= read_len;
+	}
+
+out_unlock:
+	map->unlock(map->lock_arg);
+	return ret;
+}
+EXPORT_SYMBOL_GPL(regmap_noinc_read);
+
+/**
+ * regmap_field_read(): Read a value to a single register field
  *
  * @field: Register field to read from
  * @val: Pointer to store read value