[PATCH v2 03/11] regmap: port regmap_init_spi

[Ahmad Fatoum <a.fatoum@pengutronix.de>]

We already have regmap_init_i2c, so add regmap_init_spi as well. Unlike
regmap_init_i2c, this one makes full use of the formatted regmap API.

Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
---
 drivers/base/regmap/Kconfig      |  5 ++++
 drivers/base/regmap/Makefile     |  1 +
 drivers/base/regmap/regmap-spi.c | 42 ++++++++++++++++++++++++++++++++
 include/regmap.h                 | 13 ++++++++++
 4 files changed, 61 insertions(+)
 create mode 100644 drivers/base/regmap/regmap-spi.c

diff --git a/drivers/base/regmap/Kconfig b/drivers/base/regmap/Kconfig
index 4fb6b6bcecf8..afe59a538c87 100644
--- a/drivers/base/regmap/Kconfig
+++ b/drivers/base/regmap/Kconfig
@@ -2,3 +2,8 @@
 
 config REGMAP_FORMATTED
 	bool
+
+config REGMAP_SPI
+	bool "SPI regmaps" if COMPILE_TEST
+	depends on SPI
+	select REGMAP_FORMATTED
diff --git a/drivers/base/regmap/Makefile b/drivers/base/regmap/Makefile
index ef6814a50277..d99db4277149 100644
--- a/drivers/base/regmap/Makefile
+++ b/drivers/base/regmap/Makefile
@@ -3,3 +3,4 @@ obj-y	+= regmap.o
 obj-y	+= regmap-mmio.o
 obj-$(CONFIG_REGMAP_FORMATTED)	+= regmap-fmt.o
 obj-$(CONFIG_I2C)	+= regmap-i2c.o
+obj-$(CONFIG_REGMAP_SPI)	+= regmap-spi.o
diff --git a/drivers/base/regmap/regmap-spi.c b/drivers/base/regmap/regmap-spi.c
new file mode 100644
index 000000000000..5a0e418065b8
--- /dev/null
+++ b/drivers/base/regmap/regmap-spi.c
@@ -0,0 +1,42 @@
+// SPDX-License-Identifier: GPL-2.0
+//
+// Register map access API - SPI support
+//
+// Copyright 2011 Wolfson Microelectronics plc
+//
+// Author: Mark Brown <broonie@opensource.wolfsonmicro.com>
+
+#include <regmap.h>
+#include <spi/spi.h>
+
+static int regmap_spi_write(void *context, const void *data, size_t count)
+{
+	struct device_d *dev = context;
+	struct spi_device *spi = to_spi_device(dev);
+
+	return spi_write(spi, data, count);
+}
+
+static int regmap_spi_read(void *context,
+			   const void *reg, size_t reg_size,
+			   void *val, size_t val_size)
+{
+	struct device_d *dev = context;
+	struct spi_device *spi = to_spi_device(dev);
+
+	return spi_write_then_read(spi, reg, reg_size, val, val_size);
+}
+
+static const struct regmap_bus regmap_spi = {
+	.write = regmap_spi_write,
+	.read = regmap_spi_read,
+	.read_flag_mask = 0x80,
+	.reg_format_endian_default = REGMAP_ENDIAN_BIG,
+	.val_format_endian_default = REGMAP_ENDIAN_BIG,
+};
+
+struct regmap *regmap_init_spi(struct spi_device *spi,
+			       const struct regmap_config *config)
+{
+	return regmap_init(&spi->dev, &regmap_spi, &spi->dev, config);
+}
diff --git a/include/regmap.h b/include/regmap.h
index 36a75eb34e03..8f191c87cfcb 100644
--- a/include/regmap.h
+++ b/include/regmap.h
@@ -138,6 +138,19 @@ struct regmap *regmap_init_i2c(struct i2c_client *i2c,
 struct regmap *regmap_init_i2c_smbus(struct i2c_client *client,
 			       const struct regmap_config *config);
 
+/**
+ * regmap_init_spi() - Initialise spi register map
+ *
+ * @spi: Device that will be interacted with
+ * @config: Configuration for register map
+ *
+ * The return value will be an ERR_PTR() on error or a valid pointer
+ * to a struct regmap.
+ */
+struct spi_device;
+struct regmap *regmap_init_spi(struct spi_device *dev,
+			       const struct regmap_config *config);
+
 /**
  * regmap_init_mmio() - Initialise register map
  *
-- 
2.30.2