iio: accel: adxl345: Add SPI support

Add SPI driver that initializes SPI regmap for the adxl345 core driver.
The driver supports the same functionality as I2C namely the x, y, z and
scale readings.

Signed-off-by: Eva Rachel Retuya <eraretuya@gmail.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

diff --git a/drivers/iio/accel/Kconfig b/drivers/iio/accel/Kconfig
index a725227aa7caa281e3a87d17b3dc1ff5e684d09b..15de262015df8a2b923e73232aab3f8954ae9786 100644 (file)
--- a/drivers/iio/accel/Kconfig
+++ b/drivers/iio/accel/Kconfig
@@ -22,6 +22,20 @@ config ADXL345_I2C
          will be called adxl345_i2c and you will also get adxl345_core
          for the core module.
 
+config ADXL345_SPI
+       tristate "Analog Devices ADXL345 3-Axis Digital Accelerometer SPI Driver"
+       depends on INPUT_ADXL34X=n
+       depends on SPI
+       select ADXL345
+       select REGMAP_SPI
+       help
+         Say Y here if you want to build support for the Analog Devices
+         ADXL345 3-axis digital accelerometer.
+
+         To compile this driver as a module, choose M here: the module
+         will be called adxl345_spi and you will also get adxl345_core
+         for the core module.
+
 config BMA180
        tristate "Bosch BMA180/BMA250 3-Axis Accelerometer Driver"
        depends on I2C

diff --git a/drivers/iio/accel/Makefile b/drivers/iio/accel/Makefile
index 3f4a6d62d84ca32fd7c78f3d00d460f9f75cddbe..31fba1974e9539b22d5143fe128c1369160df74b 100644 (file)
--- a/drivers/iio/accel/Makefile
+++ b/drivers/iio/accel/Makefile
@@ -5,6 +5,7 @@
 # When adding new entries keep the list in alphabetical order
 obj-$(CONFIG_ADXL345) += adxl345_core.o
 obj-$(CONFIG_ADXL345_I2C) += adxl345_i2c.o
+obj-$(CONFIG_ADXL345_SPI) += adxl345_spi.o
 obj-$(CONFIG_BMA180) += bma180.o
 obj-$(CONFIG_BMA220) += bma220_spi.o
 obj-$(CONFIG_BMC150_ACCEL) += bmc150-accel-core.o

diff --git a/drivers/iio/accel/adxl345_spi.c b/drivers/iio/accel/adxl345_spi.c
new file mode 100644 (file)
index 0000000..6d65819
--- /dev/null
+++ b/drivers/iio/accel/adxl345_spi.c
@@ -0,0 +1,81 @@
+/*
+ * ADXL345 3-Axis Digital Accelerometer SPI driver
+ *
+ * Copyright (c) 2017 Eva Rachel Retuya <eraretuya@gmail.com>
+ *
+ * This file is subject to the terms and conditions of version 2 of
+ * the GNU General Public License. See the file COPYING in the main
+ * directory of this archive for more details.
+ */
+
+#include <linux/module.h>
+#include <linux/regmap.h>
+#include <linux/spi/spi.h>
+
+#include "adxl345.h"
+
+#define ADXL345_MAX_SPI_FREQ_HZ                5000000
+
+static const struct regmap_config adxl345_spi_regmap_config = {
+       .reg_bits = 8,
+       .val_bits = 8,
+        /* Setting bits 7 and 6 enables multiple-byte read */
+       .read_flag_mask = BIT(7) | BIT(6),
+};
+
+static int adxl345_spi_probe(struct spi_device *spi)
+{
+       const struct spi_device_id *id = spi_get_device_id(spi);
+       struct regmap *regmap;
+
+       /* Bail out if max_speed_hz exceeds 5 MHz */
+       if (spi->max_speed_hz > ADXL345_MAX_SPI_FREQ_HZ) {
+               dev_err(&spi->dev, "SPI CLK, %d Hz exceeds 5 MHz\n",
+                       spi->max_speed_hz);
+               return -EINVAL;
+       }
+
+       regmap = devm_regmap_init_spi(spi, &adxl345_spi_regmap_config);
+       if (IS_ERR(regmap)) {
+               dev_err(&spi->dev, "Error initializing spi regmap: %ld\n",
+                       PTR_ERR(regmap));
+               return PTR_ERR(regmap);
+       }
+
+       return adxl345_core_probe(&spi->dev, regmap, id->name);
+}
+
+static int adxl345_spi_remove(struct spi_device *spi)
+{
+       return adxl345_core_remove(&spi->dev);
+}
+
+static const struct spi_device_id adxl345_spi_id[] = {
+       { "adxl345", 0 },
+       { }
+};
+
+MODULE_DEVICE_TABLE(spi, adxl345_spi_id);
+
+static const struct of_device_id adxl345_of_match[] = {
+       { .compatible = "adi,adxl345" },
+       { },
+};
+
+MODULE_DEVICE_TABLE(of, adxl345_of_match);
+
+static struct spi_driver adxl345_spi_driver = {
+       .driver = {
+               .name   = "adxl345_spi",
+               .of_match_table = adxl345_of_match,
+       },
+       .probe          = adxl345_spi_probe,
+       .remove         = adxl345_spi_remove,
+       .id_table       = adxl345_spi_id,
+};
+
+module_spi_driver(adxl345_spi_driver);
+
+MODULE_AUTHOR("Eva Rachel Retuya <eraretuya@gmail.com>");
+MODULE_DESCRIPTION("ADXL345 3-Axis Digital Accelerometer SPI driver");
+MODULE_LICENSE("GPL v2");