[PATCH v4 00/19] iio: accel: bma220 improvements

[PATCH v4 00/19] iio: accel: bma220 improvements

[Petre Rodan]

Series of patches that switch the driver to the regmap API and add
i2c connectivity.

Tested in I2C and SPI modes with two different sensors.

Event-related code was skipped since the patch series was getting too
large.

Bindings have been merged into testing branch, but this series is still
based on 'togreg'.

Contains fixes based on feedback from Krzysztof, David, Jonathan and Andy.

Signed-off-by: Petre Rodan <petre.rodan@subdimension.ro>
---
Changes in v4:
- fixes based on Andy's feedback
- patch reordering (Andy)
- Link to v3: https://lore.kernel.org/r/20250913-b4-bma220_improvements-v3-0-0b97279b4e45@subdimension.ro

---
Petre Rodan (19):
      iio: accel: bma220: remove incorrect kernel-doc marking
      iio: accel: bma220: relax constraints during probe()
      iio: accel: bma220: cleanup license string
      iio: accel: bma220: shorten spi->dev calls
      iio: accel: bma220: move bma220_power function
      iio: accel: bma220: cleanup includes
      iio: accel: bma220: split original driver
      iio: accel: bma220: add open firmware table
      iio: accel: bma220: turn power supplies on
      iio: accel: bma220: reset registers during init stage
      iio: accel: bma220: migrate to regmap API
      iio: accel: bma220: populate buffer ts in trigger handler
      iio: accel: bma220: use find_match_table fct
      iio: accel: bma220: add i2c module
      iio: accel: bma220: add i2c watchdog feature
      iio: accel: bma220: add interrupt trigger
      iio: accel: bma220: add LPF cut-off frequency mapping
      iio: accel: bma220: add debugfs reg access
      iio: accel: bma220: add maintainer

 MAINTAINERS                     |   7 +
 drivers/iio/accel/Kconfig       |  19 +-
 drivers/iio/accel/Makefile      |   4 +-
 drivers/iio/accel/bma220.h      |  22 ++
 drivers/iio/accel/bma220_core.c | 603 ++++++++++++++++++++++++++++++++++++++++
 drivers/iio/accel/bma220_i2c.c  |  58 ++++
 drivers/iio/accel/bma220_spi.c  | 319 ++-------------------
 7 files changed, 735 insertions(+), 297 deletions(-)
---
base-commit: 561285d048053fec8a3d6d1e3ddc60df11c393a0
change-id: 20250913-b4-bma220_improvements-ad0b3df025bb

Best regards,
-- 
Petre Rodan <petre.rodan@subdimension.ro>

[PATCH v4 01/19] iio: accel: bma220: remove incorrect kernel-doc marking

[Petre Rodan]

Remove incorrect use of kernel-doc marking.

Signed-off-by: Petre Rodan <petre.rodan@subdimension.ro>
---
v4 - split from bigger patch (Andy)
---
 drivers/iio/accel/bma220_spi.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/iio/accel/bma220_spi.c b/drivers/iio/accel/bma220_spi.c
index 01592eebf05bb6b002d44c41cca1d2dd5f28350c..505ad70912571ba629f91e56a92898d8320e976f 100644
--- a/drivers/iio/accel/bma220_spi.c
+++ b/drivers/iio/accel/bma220_spi.c
@@ -223,7 +223,7 @@ static int bma220_power(struct spi_device *spi, bool up)
 {
 	int i, ret;
 
-	/**
+	/*
 	 * The chip can be suspended/woken up by a simple register read.
 	 * So, we need up to 2 register reads of the suspend register
 	 * to make sure that the device is in the desired state.

-- 
2.49.1

Re: [PATCH v4 01/19] iio: accel: bma220: remove incorrect kernel-doc marking

[Jonathan Cameron]

On Sun, 05 Oct 2025 16:12:10 +0300
Petre Rodan <petre.rodan@subdimension.ro> wrote:

> Remove incorrect use of kernel-doc marking.
> 
> Signed-off-by: Petre Rodan <petre.rodan@subdimension.ro>

hi Petre,

I'm going to pick these up as I read through them (if they are good to go!)

Applied this one,

Thanks,

Jonathan

> ---
> v4 - split from bigger patch (Andy)
> ---
>  drivers/iio/accel/bma220_spi.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/iio/accel/bma220_spi.c b/drivers/iio/accel/bma220_spi.c
> index 01592eebf05bb6b002d44c41cca1d2dd5f28350c..505ad70912571ba629f91e56a92898d8320e976f 100644
> --- a/drivers/iio/accel/bma220_spi.c
> +++ b/drivers/iio/accel/bma220_spi.c
> @@ -223,7 +223,7 @@ static int bma220_power(struct spi_device *spi, bool up)
>  {
>  	int i, ret;
>  
> -	/**
> +	/*
>  	 * The chip can be suspended/woken up by a simple register read.
>  	 * So, we need up to 2 register reads of the suspend register
>  	 * to make sure that the device is in the desired state.
> 

[PATCH v4 02/19] iio: accel: bma220: relax constraints during probe()

[Petre Rodan]

Do not return error if the chip id being read is not the expected one.

Signed-off-by: Petre Rodan <petre.rodan@subdimension.ro>
---
v4 - split from bigger patch (Jonathan)
---
 drivers/iio/accel/bma220_spi.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/drivers/iio/accel/bma220_spi.c b/drivers/iio/accel/bma220_spi.c
index 505ad70912571ba629f91e56a92898d8320e976f..02ee6b4d51c0816a88ac258f0e5107111ec2a2bc 100644
--- a/drivers/iio/accel/bma220_spi.c
+++ b/drivers/iio/accel/bma220_spi.c
@@ -202,10 +202,15 @@ static const struct iio_info bma220_info = {
 static int bma220_init(struct spi_device *spi)
 {
 	int ret;
+	struct device *dev = &spi->dev;
 
 	ret = bma220_read_reg(spi, BMA220_REG_ID);
+	if (ret < 0)
+		return dev_err_probe(dev, ret,
+				     "Failed to read chip id register\n");
+
 	if (ret != BMA220_CHIP_ID)
-		return -ENODEV;
+		dev_info(dev, "Unknown chip found: 0x%02x\n", ret);
 
 	/* Make sure the chip is powered on */
 	ret = bma220_read_reg(spi, BMA220_REG_SUSPEND);

-- 
2.49.1

Re: [PATCH v4 02/19] iio: accel: bma220: relax constraints during probe()

[Jonathan Cameron]

On Sun, 05 Oct 2025 16:12:11 +0300
Petre Rodan <petre.rodan@subdimension.ro> wrote:

> Do not return error if the chip id being read is not the expected one.
> 
> Signed-off-by: Petre Rodan <petre.rodan@subdimension.ro>
Applied.

[PATCH v4 03/19] iio: accel: bma220: cleanup license string

[Petre Rodan]

Fix checkpatch warning about use of "GPL v2" license:

Prefer "GPL" over "GPL v2" - see commit bf7fbeeae6db
("module: Cure the MODULE_LICENSE "GPL" vs. "GPL v2" bogosity")

Signed-off-by: Petre Rodan <petre.rodan@subdimension.ro>
---
v4 - split from bigger patch (Andy)
---
 drivers/iio/accel/bma220_spi.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/iio/accel/bma220_spi.c b/drivers/iio/accel/bma220_spi.c
index 02ee6b4d51c0816a88ac258f0e5107111ec2a2bc..8c313debc1dff7f4bae7c165bc555ee190996291 100644
--- a/drivers/iio/accel/bma220_spi.c
+++ b/drivers/iio/accel/bma220_spi.c
@@ -332,4 +332,4 @@ module_spi_driver(bma220_driver);
 
 MODULE_AUTHOR("Tiberiu Breana <tiberiu.a.breana@intel.com>");
 MODULE_DESCRIPTION("BMA220 acceleration sensor driver");
-MODULE_LICENSE("GPL v2");
+MODULE_LICENSE("GPL");

-- 
2.49.1

Re: [PATCH v4 03/19] iio: accel: bma220: cleanup license string

[Jonathan Cameron]

On Sun, 05 Oct 2025 16:12:12 +0300
Petre Rodan <petre.rodan@subdimension.ro> wrote:

> Fix checkpatch warning about use of "GPL v2" license:
> 
> Prefer "GPL" over "GPL v2" - see commit bf7fbeeae6db
> ("module: Cure the MODULE_LICENSE "GPL" vs. "GPL v2" bogosity")
> 
> Signed-off-by: Petre Rodan <petre.rodan@subdimension.ro>
Applied.
> ---
> v4 - split from bigger patch (Andy)
> ---
>  drivers/iio/accel/bma220_spi.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/iio/accel/bma220_spi.c b/drivers/iio/accel/bma220_spi.c
> index 02ee6b4d51c0816a88ac258f0e5107111ec2a2bc..8c313debc1dff7f4bae7c165bc555ee190996291 100644
> --- a/drivers/iio/accel/bma220_spi.c
> +++ b/drivers/iio/accel/bma220_spi.c
> @@ -332,4 +332,4 @@ module_spi_driver(bma220_driver);
>  
>  MODULE_AUTHOR("Tiberiu Breana <tiberiu.a.breana@intel.com>");
>  MODULE_DESCRIPTION("BMA220 acceleration sensor driver");
> -MODULE_LICENSE("GPL v2");
> +MODULE_LICENSE("GPL");
> 

[PATCH v4 04/19] iio: accel: bma220: shorten spi->dev calls

[Petre Rodan]

Provide functions easier access to device struct.

Signed-off-by: Petre Rodan <petre.rodan@subdimension.ro>
---
v4 - split from bigger patch (Andy)
---
 drivers/iio/accel/bma220_spi.c | 11 ++++++-----
 1 file changed, 6 insertions(+), 5 deletions(-)

diff --git a/drivers/iio/accel/bma220_spi.c b/drivers/iio/accel/bma220_spi.c
index 8c313debc1dff7f4bae7c165bc555ee190996291..a5d2906321ae5fc67c0e1dc44651833c5e7fcb39 100644
--- a/drivers/iio/accel/bma220_spi.c
+++ b/drivers/iio/accel/bma220_spi.c
@@ -258,8 +258,9 @@ static int bma220_probe(struct spi_device *spi)
 	int ret;
 	struct iio_dev *indio_dev;
 	struct bma220_data *data;
+	struct device *dev = &spi->dev;
 
-	indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*data));
+	indio_dev = devm_iio_device_alloc(dev, sizeof(*data));
 	if (!indio_dev)
 		return -ENOMEM;
 
@@ -278,19 +279,19 @@ static int bma220_probe(struct spi_device *spi)
 	if (ret)
 		return ret;
 
-	ret = devm_add_action_or_reset(&spi->dev, bma220_deinit, spi);
+	ret = devm_add_action_or_reset(dev, bma220_deinit, spi);
 	if (ret)
 		return ret;
 
-	ret = devm_iio_triggered_buffer_setup(&spi->dev, indio_dev,
+	ret = devm_iio_triggered_buffer_setup(dev, indio_dev,
 					      iio_pollfunc_store_time,
 					      bma220_trigger_handler, NULL);
 	if (ret < 0) {
-		dev_err(&spi->dev, "iio triggered buffer setup failed\n");
+		dev_err(dev, "iio triggered buffer setup failed\n");
 		return ret;
 	}
 
-	return devm_iio_device_register(&spi->dev, indio_dev);
+	return devm_iio_device_register(dev, indio_dev);
 }
 
 static int bma220_suspend(struct device *dev)

-- 
2.49.1

Re: [PATCH v4 04/19] iio: accel: bma220: shorten spi->dev calls

[Jonathan Cameron]

On Sun, 05 Oct 2025 16:12:13 +0300
Petre Rodan <petre.rodan@subdimension.ro> wrote:

> Provide functions easier access to device struct.
> 
> Signed-off-by: Petre Rodan <petre.rodan@subdimension.ro>
Applied.

[PATCH v4 05/19] iio: accel: bma220: move bma220_power function

[Petre Rodan]

Move bma220_power() before bma220_init() as a precursor to a
patch that removes code duplication.

Signed-off-by: Petre Rodan <petre.rodan@subdimension.ro>
---
v3->v4
- unsigned i (Andy)
---
 drivers/iio/accel/bma220_spi.c | 49 +++++++++++++++++++++---------------------
 1 file changed, 25 insertions(+), 24 deletions(-)

diff --git a/drivers/iio/accel/bma220_spi.c b/drivers/iio/accel/bma220_spi.c
index a5d2906321ae5fc67c0e1dc44651833c5e7fcb39..45ac0d7ee27de65b204bd2766f26024e4ed57f4c 100644
--- a/drivers/iio/accel/bma220_spi.c
+++ b/drivers/iio/accel/bma220_spi.c
@@ -199,6 +199,31 @@ static const struct iio_info bma220_info = {
 	.read_avail		= bma220_read_avail,
 };
 
+static int bma220_power(struct spi_device *spi, bool up)
+{
+	int ret;
+	unsigned int i;
+
+	/*
+	 * The chip can be suspended/woken up by a simple register read.
+	 * So, we need up to 2 register reads of the suspend register
+	 * to make sure that the device is in the desired state.
+	 */
+	for (i = 0; i < 2; i++) {
+		ret = bma220_read_reg(spi, BMA220_REG_SUSPEND);
+		if (ret < 0)
+			return ret;
+
+		if (up && ret == BMA220_SUSPEND_SLEEP)
+			return 0;
+
+		if (!up && ret == BMA220_SUSPEND_WAKE)
+			return 0;
+	}
+
+	return -EBUSY;
+}
+
 static int bma220_init(struct spi_device *spi)
 {
 	int ret;
@@ -224,30 +249,6 @@ static int bma220_init(struct spi_device *spi)
 	return 0;
 }
 
-static int bma220_power(struct spi_device *spi, bool up)
-{
-	int i, ret;
-
-	/*
-	 * The chip can be suspended/woken up by a simple register read.
-	 * So, we need up to 2 register reads of the suspend register
-	 * to make sure that the device is in the desired state.
-	 */
-	for (i = 0; i < 2; i++) {
-		ret = bma220_read_reg(spi, BMA220_REG_SUSPEND);
-		if (ret < 0)
-			return ret;
-
-		if (up && ret == BMA220_SUSPEND_SLEEP)
-			return 0;
-
-		if (!up && ret == BMA220_SUSPEND_WAKE)
-			return 0;
-	}
-
-	return -EBUSY;
-}
-
 static void bma220_deinit(void *spi)
 {
 	bma220_power(spi, false);

-- 
2.49.1

Re: [PATCH v4 05/19] iio: accel: bma220: move bma220_power function

[Jonathan Cameron]

On Sun, 05 Oct 2025 16:12:14 +0300
Petre Rodan <petre.rodan@subdimension.ro> wrote:

> Move bma220_power() before bma220_init() as a precursor to a
> patch that removes code duplication.
> 
> Signed-off-by: Petre Rodan <petre.rodan@subdimension.ro>
Applied.

[PATCH v4 06/19] iio: accel: bma220: cleanup includes

[Petre Rodan]

Tweak includes based on requirements.

Signed-off-by: Petre Rodan <petre.rodan@subdimension.ro>
---
v4 split from bigger patch (Andy)
---
 drivers/iio/accel/bma220_spi.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/iio/accel/bma220_spi.c b/drivers/iio/accel/bma220_spi.c
index 45ac0d7ee27de65b204bd2766f26024e4ed57f4c..abff24a48e5aaa5efb05cdf1924ffea24f4da4c5 100644
--- a/drivers/iio/accel/bma220_spi.c
+++ b/drivers/iio/accel/bma220_spi.c
@@ -6,9 +6,10 @@
  */
 
 #include <linux/bits.h>
-#include <linux/kernel.h>
 #include <linux/mod_devicetable.h>
 #include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/pm.h>
 #include <linux/types.h>
 #include <linux/spi/spi.h>
 

-- 
2.49.1

Re: [PATCH v4 06/19] iio: accel: bma220: cleanup includes

[Jonathan Cameron]

On Sun, 05 Oct 2025 16:12:15 +0300
Petre Rodan <petre.rodan@subdimension.ro> wrote:

> Tweak includes based on requirements.
> 
> Signed-off-by: Petre Rodan <petre.rodan@subdimension.ro>
Applied.

Re: [PATCH v4 06/19] iio: accel: bma220: cleanup includes

[Jonathan Cameron]

On Sun, 05 Oct 2025 16:12:15 +0300
Petre Rodan <petre.rodan@subdimension.ro> wrote:

> Tweak includes based on requirements.
> 
> Signed-off-by: Petre Rodan <petre.rodan@subdimension.ro>
see next patch. I tweaked this as below
> ---
> v4 split from bigger patch (Andy)
> ---
>  drivers/iio/accel/bma220_spi.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/iio/accel/bma220_spi.c b/drivers/iio/accel/bma220_spi.c
> index 45ac0d7ee27de65b204bd2766f26024e4ed57f4c..abff24a48e5aaa5efb05cdf1924ffea24f4da4c5 100644
> --- a/drivers/iio/accel/bma220_spi.c
> +++ b/drivers/iio/accel/bma220_spi.c
> @@ -6,9 +6,10 @@
>   */
>  
>  #include <linux/bits.h>

#include <linux/errno.h>

which otherwise was added in next patch with no related code changes that I could spot.
It definitely should be here for EBUSY etc.

> -#include <linux/kernel.h>
>  #include <linux/mod_devicetable.h>
>  #include <linux/module.h>
> +#include <linux/mutex.h>
> +#include <linux/pm.h>
>  #include <linux/types.h>
>  #include <linux/spi/spi.h>
>  
> 

[PATCH v4 07/19] iio: accel: bma220: split original driver

[Petre Rodan]

In preparation for the i2c module, move the original code into multiple
source files without any other functional change.

Create the additional bma220_core module which currently is not
providing an abstracted bus type (this will change with the regmap
patch).
Fix a few includes in the context of this patch.

Signed-off-by: Petre Rodan <petre.rodan@subdimension.ro>
---
v1->v2
- split out open firmware table modification into separate patch
- bma220_write_raw() exits without dev_err() based on similar feedback
  from David
- change includes in bma220.h (Jonathan)
- include bma220.h in bma220_core.c (Jonathan)
- add mutex.h and pm.h includes to bma220_core.c
- cleanup struct spacing in bma220_spi.c
v2->v3
- keep depends on SPI (David)
- fix a few includes in bma220_spi.c (Jonathan)
v2->v3
- keep depends on SPI (David)
- fix a few includes in bma220_spi.c (Jonathan)
- mention new includes in commit body (Jonathan)
v4 move some of the changes into precursor patches (01-07) (Andy)
---
 drivers/iio/accel/Kconfig       |   8 +-
 drivers/iio/accel/Makefile      |   3 +-
 drivers/iio/accel/bma220.h      |  18 +++
 drivers/iio/accel/bma220_core.c | 319 ++++++++++++++++++++++++++++++++++++++++
 drivers/iio/accel/bma220_spi.c  | 314 ++-------------------------------------
 5 files changed, 357 insertions(+), 305 deletions(-)

diff --git a/drivers/iio/accel/Kconfig b/drivers/iio/accel/Kconfig
index 8c3f7cf55d5fa432a4d4662b184a46cd59c3ebca..4648be329917a3054615ed324156d67f53baefb6 100644
--- a/drivers/iio/accel/Kconfig
+++ b/drivers/iio/accel/Kconfig
@@ -221,12 +221,18 @@ config BMA220
 	depends on SPI
 	select IIO_BUFFER
 	select IIO_TRIGGERED_BUFFER
+	select BMA220_SPI if SPI
 	help
 	  Say yes here to add support for the Bosch BMA220 triaxial
 	  acceleration sensor.
 
 	  To compile this driver as a module, choose M here: the
-	  module will be called bma220_spi.
+	  module will be called bma220_core and you will also get
+	  bma220_spi if SPI is enabled.
+
+config BMA220_SPI
+	tristate
+	depends on BMA220
 
 config BMA400
 	tristate "Bosch BMA400 3-Axis Accelerometer Driver"
diff --git a/drivers/iio/accel/Makefile b/drivers/iio/accel/Makefile
index ca8569e25aba31c3ae3437abf8506addbf5edffa..56a9f848f7f913633bc2a628c1ac5c9190774b9d 100644
--- a/drivers/iio/accel/Makefile
+++ b/drivers/iio/accel/Makefile
@@ -25,7 +25,8 @@ obj-$(CONFIG_ADXL380) += adxl380.o
 obj-$(CONFIG_ADXL380_I2C) += adxl380_i2c.o
 obj-$(CONFIG_ADXL380_SPI) += adxl380_spi.o
 obj-$(CONFIG_BMA180) += bma180.o
-obj-$(CONFIG_BMA220) += bma220_spi.o
+obj-$(CONFIG_BMA220) += bma220_core.o
+obj-$(CONFIG_BMA220_SPI) += bma220_spi.o
 obj-$(CONFIG_BMA400) += bma400_core.o
 obj-$(CONFIG_BMA400_I2C) += bma400_i2c.o
 obj-$(CONFIG_BMA400_SPI) += bma400_spi.o
diff --git a/drivers/iio/accel/bma220.h b/drivers/iio/accel/bma220.h
new file mode 100644
index 0000000000000000000000000000000000000000..dea34244b4fc4971841dc60d79db6c7db27bea20
--- /dev/null
+++ b/drivers/iio/accel/bma220.h
@@ -0,0 +1,18 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Forward declarations needed by the bma220 sources.
+ *
+ * Copyright 2025 Petre Rodan <petre.rodan@subdimension.ro>
+ */
+
+#ifndef _BMA220_H
+#define _BMA220_H
+
+#include <linux/pm.h>
+
+extern const struct dev_pm_ops bma220_pm_ops;
+struct spi_device;
+
+int bma220_common_probe(struct spi_device *dev);
+
+#endif
diff --git a/drivers/iio/accel/bma220_core.c b/drivers/iio/accel/bma220_core.c
new file mode 100644
index 0000000000000000000000000000000000000000..00fe1064486aa469f7ad15593027c7ec86197365
--- /dev/null
+++ b/drivers/iio/accel/bma220_core.c
@@ -0,0 +1,319 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * BMA220 Digital triaxial acceleration sensor driver
+ *
+ * Copyright (c) 2016,2020 Intel Corporation.
+ */
+
+#include <linux/bits.h>
+#include <linux/mod_devicetable.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/pm.h>
+#include <linux/types.h>
+#include <linux/spi/spi.h>
+
+#include <linux/iio/buffer.h>
+#include <linux/iio/iio.h>
+#include <linux/iio/sysfs.h>
+#include <linux/iio/trigger_consumer.h>
+#include <linux/iio/triggered_buffer.h>
+
+#include "bma220.h"
+
+#define BMA220_REG_ID				0x00
+#define BMA220_REG_ACCEL_X			0x02
+#define BMA220_REG_ACCEL_Y			0x03
+#define BMA220_REG_ACCEL_Z			0x04
+#define BMA220_REG_RANGE			0x11
+#define BMA220_REG_SUSPEND			0x18
+
+#define BMA220_CHIP_ID				0xDD
+#define BMA220_READ_MASK			BIT(7)
+#define BMA220_RANGE_MASK			GENMASK(1, 0)
+#define BMA220_SUSPEND_SLEEP			0xFF
+#define BMA220_SUSPEND_WAKE			0x00
+
+#define BMA220_DEVICE_NAME			"bma220"
+
+#define BMA220_ACCEL_CHANNEL(index, reg, axis) {			\
+	.type = IIO_ACCEL,						\
+	.address = reg,							\
+	.modified = 1,							\
+	.channel2 = IIO_MOD_##axis,					\
+	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),			\
+	.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),		\
+	.scan_index = index,						\
+	.scan_type = {							\
+		.sign = 's',						\
+		.realbits = 6,						\
+		.storagebits = 8,					\
+		.shift = 2,						\
+		.endianness = IIO_CPU,					\
+	},								\
+}
+
+enum bma220_axis {
+	AXIS_X,
+	AXIS_Y,
+	AXIS_Z,
+};
+
+static const int bma220_scale_table[][2] = {
+	{0, 623000}, {1, 248000}, {2, 491000}, {4, 983000},
+};
+
+struct bma220_data {
+	struct spi_device *spi_device;
+	struct mutex lock;
+	struct {
+		s8 chans[3];
+		/* Ensure timestamp is naturally aligned. */
+		aligned_s64 timestamp;
+	} scan;
+	u8 tx_buf[2] __aligned(IIO_DMA_MINALIGN);
+};
+
+static const struct iio_chan_spec bma220_channels[] = {
+	BMA220_ACCEL_CHANNEL(0, BMA220_REG_ACCEL_X, X),
+	BMA220_ACCEL_CHANNEL(1, BMA220_REG_ACCEL_Y, Y),
+	BMA220_ACCEL_CHANNEL(2, BMA220_REG_ACCEL_Z, Z),
+	IIO_CHAN_SOFT_TIMESTAMP(3),
+};
+
+static inline int bma220_read_reg(struct spi_device *spi, u8 reg)
+{
+	return spi_w8r8(spi, reg | BMA220_READ_MASK);
+}
+
+static const unsigned long bma220_accel_scan_masks[] = {
+	BIT(AXIS_X) | BIT(AXIS_Y) | BIT(AXIS_Z),
+	0
+};
+
+static irqreturn_t bma220_trigger_handler(int irq, void *p)
+{
+	int ret;
+	struct iio_poll_func *pf = p;
+	struct iio_dev *indio_dev = pf->indio_dev;
+	struct bma220_data *data = iio_priv(indio_dev);
+	struct spi_device *spi = data->spi_device;
+
+	mutex_lock(&data->lock);
+	data->tx_buf[0] = BMA220_REG_ACCEL_X | BMA220_READ_MASK;
+	ret = spi_write_then_read(spi, data->tx_buf, 1, &data->scan.chans,
+				  ARRAY_SIZE(bma220_channels) - 1);
+	if (ret < 0)
+		goto err;
+
+	iio_push_to_buffers_with_ts(indio_dev, &data->scan, sizeof(data->scan),
+				    pf->timestamp);
+err:
+	mutex_unlock(&data->lock);
+	iio_trigger_notify_done(indio_dev->trig);
+
+	return IRQ_HANDLED;
+}
+
+static int bma220_read_raw(struct iio_dev *indio_dev,
+			   struct iio_chan_spec const *chan,
+			   int *val, int *val2, long mask)
+{
+	int ret;
+	u8 range_idx;
+	struct bma220_data *data = iio_priv(indio_dev);
+
+	switch (mask) {
+	case IIO_CHAN_INFO_RAW:
+		ret = bma220_read_reg(data->spi_device, chan->address);
+		if (ret < 0)
+			return -EINVAL;
+		*val = sign_extend32(ret >> chan->scan_type.shift,
+				     chan->scan_type.realbits - 1);
+		return IIO_VAL_INT;
+	case IIO_CHAN_INFO_SCALE:
+		ret = bma220_read_reg(data->spi_device, BMA220_REG_RANGE);
+		if (ret < 0)
+			return ret;
+		range_idx = ret & BMA220_RANGE_MASK;
+		*val = bma220_scale_table[range_idx][0];
+		*val2 = bma220_scale_table[range_idx][1];
+		return IIO_VAL_INT_PLUS_MICRO;
+	}
+
+	return -EINVAL;
+}
+
+static int bma220_write_raw(struct iio_dev *indio_dev,
+			    struct iio_chan_spec const *chan,
+			    int val, int val2, long mask)
+{
+	int i;
+	int ret;
+	int index = -1;
+	struct bma220_data *data = iio_priv(indio_dev);
+
+	switch (mask) {
+	case IIO_CHAN_INFO_SCALE:
+		for (i = 0; i < ARRAY_SIZE(bma220_scale_table); i++)
+			if (val == bma220_scale_table[i][0] &&
+			    val2 == bma220_scale_table[i][1]) {
+				index = i;
+				break;
+			}
+		if (index < 0)
+			return -EINVAL;
+
+		mutex_lock(&data->lock);
+		data->tx_buf[0] = BMA220_REG_RANGE;
+		data->tx_buf[1] = index;
+		ret = spi_write(data->spi_device, data->tx_buf,
+				sizeof(data->tx_buf));
+		if (ret < 0)
+			return ret;
+		mutex_unlock(&data->lock);
+
+		return 0;
+	}
+
+	return -EINVAL;
+}
+
+static int bma220_read_avail(struct iio_dev *indio_dev,
+			     struct iio_chan_spec const *chan,
+			     const int **vals, int *type, int *length,
+			     long mask)
+{
+	switch (mask) {
+	case IIO_CHAN_INFO_SCALE:
+		*vals = (int *)bma220_scale_table;
+		*type = IIO_VAL_INT_PLUS_MICRO;
+		*length = ARRAY_SIZE(bma220_scale_table) * 2;
+		return IIO_AVAIL_LIST;
+	default:
+		return -EINVAL;
+	}
+}
+
+static const struct iio_info bma220_info = {
+	.read_raw		= bma220_read_raw,
+	.write_raw		= bma220_write_raw,
+	.read_avail		= bma220_read_avail,
+};
+
+static int bma220_power(struct spi_device *spi, bool up)
+{
+	int ret;
+	unsigned int i;
+
+	/*
+	 * The chip can be suspended/woken up by a simple register read.
+	 * So, we need up to 2 register reads of the suspend register
+	 * to make sure that the device is in the desired state.
+	 */
+	for (i = 0; i < 2; i++) {
+		ret = bma220_read_reg(spi, BMA220_REG_SUSPEND);
+		if (ret < 0)
+			return ret;
+
+		if (up && ret == BMA220_SUSPEND_SLEEP)
+			return 0;
+
+		if (!up && ret == BMA220_SUSPEND_WAKE)
+			return 0;
+	}
+
+	return -EBUSY;
+}
+
+static int bma220_init(struct spi_device *spi)
+{
+	int ret;
+	struct device *dev = &spi->dev;
+
+	ret = bma220_read_reg(spi, BMA220_REG_ID);
+	if (ret < 0)
+		return dev_err_probe(dev, ret,
+				     "Failed to read chip id register\n");
+
+	if (ret != BMA220_CHIP_ID)
+		dev_info(dev, "Unknown chip found: 0x%02x\n", ret);
+
+	/* Make sure the chip is powered on */
+	ret = bma220_read_reg(spi, BMA220_REG_SUSPEND);
+	if (ret == BMA220_SUSPEND_WAKE)
+		ret = bma220_read_reg(spi, BMA220_REG_SUSPEND);
+	if (ret < 0)
+		return ret;
+	if (ret == BMA220_SUSPEND_WAKE)
+		return -EBUSY;
+
+	return 0;
+}
+
+static void bma220_deinit(void *spi)
+{
+	bma220_power(spi, false);
+}
+
+int bma220_common_probe(struct spi_device *spi)
+{
+	int ret;
+	struct iio_dev *indio_dev;
+	struct bma220_data *data;
+	struct device *dev = &spi->dev;
+
+	indio_dev = devm_iio_device_alloc(dev, sizeof(*data));
+	if (!indio_dev)
+		return -ENOMEM;
+
+	data = iio_priv(indio_dev);
+	data->spi_device = spi;
+	mutex_init(&data->lock);
+
+	indio_dev->info = &bma220_info;
+	indio_dev->name = BMA220_DEVICE_NAME;
+	indio_dev->modes = INDIO_DIRECT_MODE;
+	indio_dev->channels = bma220_channels;
+	indio_dev->num_channels = ARRAY_SIZE(bma220_channels);
+	indio_dev->available_scan_masks = bma220_accel_scan_masks;
+
+	ret = bma220_init(data->spi_device);
+	if (ret)
+		return ret;
+
+	ret = devm_add_action_or_reset(dev, bma220_deinit, spi);
+	if (ret)
+		return ret;
+
+	ret = devm_iio_triggered_buffer_setup(dev, indio_dev,
+					      iio_pollfunc_store_time,
+					      bma220_trigger_handler, NULL);
+	if (ret < 0) {
+		dev_err(dev, "iio triggered buffer setup failed\n");
+		return ret;
+	}
+
+	return devm_iio_device_register(dev, indio_dev);
+}
+EXPORT_SYMBOL_NS(bma220_common_probe, "IIO_BOSCH_BMA220");
+
+static int bma220_suspend(struct device *dev)
+{
+	struct spi_device *spi = to_spi_device(dev);
+
+	return bma220_power(spi, false);
+}
+
+static int bma220_resume(struct device *dev)
+{
+	struct spi_device *spi = to_spi_device(dev);
+
+	return bma220_power(spi, true);
+}
+EXPORT_NS_SIMPLE_DEV_PM_OPS(bma220_pm_ops, bma220_suspend, bma220_resume,
+			    IIO_BOSCH_BMA220);
+
+MODULE_AUTHOR("Tiberiu Breana <tiberiu.a.breana@intel.com>");
+MODULE_DESCRIPTION("BMA220 acceleration sensor driver");
+MODULE_LICENSE("GPL");
diff --git a/drivers/iio/accel/bma220_spi.c b/drivers/iio/accel/bma220_spi.c
index abff24a48e5aaa5efb05cdf1924ffea24f4da4c5..70b8bd94895e95936c7294271b5d46d9ec9903c6 100644
--- a/drivers/iio/accel/bma220_spi.c
+++ b/drivers/iio/accel/bma220_spi.c
@@ -5,334 +5,42 @@
  * Copyright (c) 2016,2020 Intel Corporation.
  */
 
-#include <linux/bits.h>
+#include <linux/errno.h>
 #include <linux/mod_devicetable.h>
 #include <linux/module.h>
-#include <linux/mutex.h>
-#include <linux/pm.h>
 #include <linux/types.h>
 #include <linux/spi/spi.h>
 
-#include <linux/iio/buffer.h>
-#include <linux/iio/iio.h>
-#include <linux/iio/sysfs.h>
-#include <linux/iio/trigger_consumer.h>
-#include <linux/iio/triggered_buffer.h>
+#include "bma220.h"
 
-#define BMA220_REG_ID				0x00
-#define BMA220_REG_ACCEL_X			0x02
-#define BMA220_REG_ACCEL_Y			0x03
-#define BMA220_REG_ACCEL_Z			0x04
-#define BMA220_REG_RANGE			0x11
-#define BMA220_REG_SUSPEND			0x18
-
-#define BMA220_CHIP_ID				0xDD
-#define BMA220_READ_MASK			BIT(7)
-#define BMA220_RANGE_MASK			GENMASK(1, 0)
-#define BMA220_SUSPEND_SLEEP			0xFF
-#define BMA220_SUSPEND_WAKE			0x00
-
-#define BMA220_DEVICE_NAME			"bma220"
-
-#define BMA220_ACCEL_CHANNEL(index, reg, axis) {			\
-	.type = IIO_ACCEL,						\
-	.address = reg,							\
-	.modified = 1,							\
-	.channel2 = IIO_MOD_##axis,					\
-	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),			\
-	.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),		\
-	.scan_index = index,						\
-	.scan_type = {							\
-		.sign = 's',						\
-		.realbits = 6,						\
-		.storagebits = 8,					\
-		.shift = 2,						\
-		.endianness = IIO_CPU,					\
-	},								\
-}
-
-enum bma220_axis {
-	AXIS_X,
-	AXIS_Y,
-	AXIS_Z,
-};
-
-static const int bma220_scale_table[][2] = {
-	{0, 623000}, {1, 248000}, {2, 491000}, {4, 983000},
-};
-
-struct bma220_data {
-	struct spi_device *spi_device;
-	struct mutex lock;
-	struct {
-		s8 chans[3];
-		/* Ensure timestamp is naturally aligned. */
-		aligned_s64 timestamp;
-	} scan;
-	u8 tx_buf[2] __aligned(IIO_DMA_MINALIGN);
-};
-
-static const struct iio_chan_spec bma220_channels[] = {
-	BMA220_ACCEL_CHANNEL(0, BMA220_REG_ACCEL_X, X),
-	BMA220_ACCEL_CHANNEL(1, BMA220_REG_ACCEL_Y, Y),
-	BMA220_ACCEL_CHANNEL(2, BMA220_REG_ACCEL_Z, Z),
-	IIO_CHAN_SOFT_TIMESTAMP(3),
-};
-
-static inline int bma220_read_reg(struct spi_device *spi, u8 reg)
+static int bma220_spi_probe(struct spi_device *spi)
 {
-	return spi_w8r8(spi, reg | BMA220_READ_MASK);
-}
-
-static const unsigned long bma220_accel_scan_masks[] = {
-	BIT(AXIS_X) | BIT(AXIS_Y) | BIT(AXIS_Z),
-	0
-};
-
-static irqreturn_t bma220_trigger_handler(int irq, void *p)
-{
-	int ret;
-	struct iio_poll_func *pf = p;
-	struct iio_dev *indio_dev = pf->indio_dev;
-	struct bma220_data *data = iio_priv(indio_dev);
-	struct spi_device *spi = data->spi_device;
-
-	mutex_lock(&data->lock);
-	data->tx_buf[0] = BMA220_REG_ACCEL_X | BMA220_READ_MASK;
-	ret = spi_write_then_read(spi, data->tx_buf, 1, &data->scan.chans,
-				  ARRAY_SIZE(bma220_channels) - 1);
-	if (ret < 0)
-		goto err;
-
-	iio_push_to_buffers_with_ts(indio_dev, &data->scan, sizeof(data->scan),
-				    pf->timestamp);
-err:
-	mutex_unlock(&data->lock);
-	iio_trigger_notify_done(indio_dev->trig);
-
-	return IRQ_HANDLED;
-}
-
-static int bma220_read_raw(struct iio_dev *indio_dev,
-			   struct iio_chan_spec const *chan,
-			   int *val, int *val2, long mask)
-{
-	int ret;
-	u8 range_idx;
-	struct bma220_data *data = iio_priv(indio_dev);
-
-	switch (mask) {
-	case IIO_CHAN_INFO_RAW:
-		ret = bma220_read_reg(data->spi_device, chan->address);
-		if (ret < 0)
-			return -EINVAL;
-		*val = sign_extend32(ret >> chan->scan_type.shift,
-				     chan->scan_type.realbits - 1);
-		return IIO_VAL_INT;
-	case IIO_CHAN_INFO_SCALE:
-		ret = bma220_read_reg(data->spi_device, BMA220_REG_RANGE);
-		if (ret < 0)
-			return ret;
-		range_idx = ret & BMA220_RANGE_MASK;
-		*val = bma220_scale_table[range_idx][0];
-		*val2 = bma220_scale_table[range_idx][1];
-		return IIO_VAL_INT_PLUS_MICRO;
-	}
-
-	return -EINVAL;
-}
-
-static int bma220_write_raw(struct iio_dev *indio_dev,
-			    struct iio_chan_spec const *chan,
-			    int val, int val2, long mask)
-{
-	int i;
-	int ret;
-	int index = -1;
-	struct bma220_data *data = iio_priv(indio_dev);
-
-	switch (mask) {
-	case IIO_CHAN_INFO_SCALE:
-		for (i = 0; i < ARRAY_SIZE(bma220_scale_table); i++)
-			if (val == bma220_scale_table[i][0] &&
-			    val2 == bma220_scale_table[i][1]) {
-				index = i;
-				break;
-			}
-		if (index < 0)
-			return -EINVAL;
-
-		mutex_lock(&data->lock);
-		data->tx_buf[0] = BMA220_REG_RANGE;
-		data->tx_buf[1] = index;
-		ret = spi_write(data->spi_device, data->tx_buf,
-				sizeof(data->tx_buf));
-		if (ret < 0)
-			dev_err(&data->spi_device->dev,
-				"failed to set measurement range\n");
-		mutex_unlock(&data->lock);
-
-		return 0;
-	}
-
-	return -EINVAL;
-}
-
-static int bma220_read_avail(struct iio_dev *indio_dev,
-			     struct iio_chan_spec const *chan,
-			     const int **vals, int *type, int *length,
-			     long mask)
-{
-	switch (mask) {
-	case IIO_CHAN_INFO_SCALE:
-		*vals = (int *)bma220_scale_table;
-		*type = IIO_VAL_INT_PLUS_MICRO;
-		*length = ARRAY_SIZE(bma220_scale_table) * 2;
-		return IIO_AVAIL_LIST;
-	default:
-		return -EINVAL;
-	}
-}
-
-static const struct iio_info bma220_info = {
-	.read_raw		= bma220_read_raw,
-	.write_raw		= bma220_write_raw,
-	.read_avail		= bma220_read_avail,
-};
-
-static int bma220_power(struct spi_device *spi, bool up)
-{
-	int ret;
-	unsigned int i;
-
-	/*
-	 * The chip can be suspended/woken up by a simple register read.
-	 * So, we need up to 2 register reads of the suspend register
-	 * to make sure that the device is in the desired state.
-	 */
-	for (i = 0; i < 2; i++) {
-		ret = bma220_read_reg(spi, BMA220_REG_SUSPEND);
-		if (ret < 0)
-			return ret;
-
-		if (up && ret == BMA220_SUSPEND_SLEEP)
-			return 0;
-
-		if (!up && ret == BMA220_SUSPEND_WAKE)
-			return 0;
-	}
-
-	return -EBUSY;
-}
-
-static int bma220_init(struct spi_device *spi)
-{
-	int ret;
-	struct device *dev = &spi->dev;
-
-	ret = bma220_read_reg(spi, BMA220_REG_ID);
-	if (ret < 0)
-		return dev_err_probe(dev, ret,
-				     "Failed to read chip id register\n");
-
-	if (ret != BMA220_CHIP_ID)
-		dev_info(dev, "Unknown chip found: 0x%02x\n", ret);
-
-	/* Make sure the chip is powered on */
-	ret = bma220_read_reg(spi, BMA220_REG_SUSPEND);
-	if (ret == BMA220_SUSPEND_WAKE)
-		ret = bma220_read_reg(spi, BMA220_REG_SUSPEND);
-	if (ret < 0)
-		return ret;
-	if (ret == BMA220_SUSPEND_WAKE)
-		return -EBUSY;
-
-	return 0;
-}
-
-static void bma220_deinit(void *spi)
-{
-	bma220_power(spi, false);
-}
-
-static int bma220_probe(struct spi_device *spi)
-{
-	int ret;
-	struct iio_dev *indio_dev;
-	struct bma220_data *data;
-	struct device *dev = &spi->dev;
-
-	indio_dev = devm_iio_device_alloc(dev, sizeof(*data));
-	if (!indio_dev)
-		return -ENOMEM;
-
-	data = iio_priv(indio_dev);
-	data->spi_device = spi;
-	mutex_init(&data->lock);
-
-	indio_dev->info = &bma220_info;
-	indio_dev->name = BMA220_DEVICE_NAME;
-	indio_dev->modes = INDIO_DIRECT_MODE;
-	indio_dev->channels = bma220_channels;
-	indio_dev->num_channels = ARRAY_SIZE(bma220_channels);
-	indio_dev->available_scan_masks = bma220_accel_scan_masks;
-
-	ret = bma220_init(data->spi_device);
-	if (ret)
-		return ret;
-
-	ret = devm_add_action_or_reset(dev, bma220_deinit, spi);
-	if (ret)
-		return ret;
-
-	ret = devm_iio_triggered_buffer_setup(dev, indio_dev,
-					      iio_pollfunc_store_time,
-					      bma220_trigger_handler, NULL);
-	if (ret < 0) {
-		dev_err(dev, "iio triggered buffer setup failed\n");
-		return ret;
-	}
-
-	return devm_iio_device_register(dev, indio_dev);
-}
-
-static int bma220_suspend(struct device *dev)
-{
-	struct spi_device *spi = to_spi_device(dev);
-
-	return bma220_power(spi, false);
-}
-
-static int bma220_resume(struct device *dev)
-{
-	struct spi_device *spi = to_spi_device(dev);
-
-	return bma220_power(spi, true);
+	return bma220_common_probe(spi);
 }
-static DEFINE_SIMPLE_DEV_PM_OPS(bma220_pm_ops, bma220_suspend, bma220_resume);
 
 static const struct spi_device_id bma220_spi_id[] = {
-	{"bma220", 0},
+	{ "bma220", 0 },
 	{ }
 };
 
 static const struct acpi_device_id bma220_acpi_id[] = {
-	{"BMA0220", 0},
+	{ "BMA0220", 0 },
 	{ }
 };
 MODULE_DEVICE_TABLE(spi, bma220_spi_id);
 
-static struct spi_driver bma220_driver = {
+static struct spi_driver bma220_spi_driver = {
 	.driver = {
 		.name = "bma220_spi",
 		.pm = pm_sleep_ptr(&bma220_pm_ops),
 		.acpi_match_table = bma220_acpi_id,
 	},
-	.probe =            bma220_probe,
+	.probe =            bma220_spi_probe,
 	.id_table =         bma220_spi_id,
 };
-module_spi_driver(bma220_driver);
+module_spi_driver(bma220_spi_driver);
 
 MODULE_AUTHOR("Tiberiu Breana <tiberiu.a.breana@intel.com>");
-MODULE_DESCRIPTION("BMA220 acceleration sensor driver");
+MODULE_DESCRIPTION("BMA220 triaxial acceleration sensor spi driver");
 MODULE_LICENSE("GPL");
+MODULE_IMPORT_NS("IIO_BOSCH_BMA220");

-- 
2.49.1

Re: [PATCH v4 07/19] iio: accel: bma220: split original driver

[Jonathan Cameron]

On Sun, 05 Oct 2025 16:12:16 +0300
Petre Rodan <petre.rodan@subdimension.ro> wrote:

> In preparation for the i2c module, move the original code into multiple
> source files without any other functional change.
> 
> Create the additional bma220_core module which currently is not
> providing an abstracted bus type (this will change with the regmap
> patch).
> Fix a few includes in the context of this patch.
> 
> Signed-off-by: Petre Rodan <petre.rodan@subdimension.ro>

It required a bit of hand tweaking after the include tweak I made in the previous patch.
Also due to comments in here I tweaked a bit more:

Please check the result on the iio.git / testing branch.

Whilst I'm not entirely sure Andy won't want to take another look at this it
seemed ok to apply a bit speculatively,

Thanks,

Jonathan

diff --git a/drivers/iio/accel/bma220_core.c b/drivers/iio/accel/bma220_core.c
index 00fe1064486a..050282f20d90 100644
--- a/drivers/iio/accel/bma220_core.c
+++ b/drivers/iio/accel/bma220_core.c
@@ -6,6 +6,7 @@
  */
 
 #include <linux/bits.h>
+#include <linux/errno.h>
 #include <linux/mod_devicetable.h>
 #include <linux/module.h>
 #include <linux/mutex.h>
diff --git a/drivers/iio/accel/bma220_spi.c b/drivers/iio/accel/bma220_spi.c
index 70b8bd94895e..761f475a5942 100644
--- a/drivers/iio/accel/bma220_spi.c
+++ b/drivers/iio/accel/bma220_spi.c
@@ -5,7 +5,6 @@
  * Copyright (c) 2016,2020 Intel Corporation.
  */
 
-#include <linux/errno.h>
 #include <linux/mod_devicetable.h>
 #include <linux/module.h>
 #include <linux/types.h>
@@ -19,12 +18,12 @@ static int bma220_spi_probe(struct spi_device *spi)
 }
 
 static const struct spi_device_id bma220_spi_id[] = {
-       { "bma220", 0 },
+       {"bma220", 0},
        { }
 };
 
 static const struct acpi_device_id bma220_acpi_id[] = {
-       { "BMA0220", 0 },
+       {"BMA0220", 0},
        { }
 };
 MODULE_DEVICE_TABLE(spi, bma220_spi_id);

> ---
> v1->v2
> - split out open firmware table modification into separate patch
> - bma220_write_raw() exits without dev_err() based on similar feedback
>   from David
> - change includes in bma220.h (Jonathan)
> - include bma220.h in bma220_core.c (Jonathan)
> - add mutex.h and pm.h includes to bma220_core.c
> - cleanup struct spacing in bma220_spi.c
> v2->v3
> - keep depends on SPI (David)
> - fix a few includes in bma220_spi.c (Jonathan)
> v2->v3
> - keep depends on SPI (David)
> - fix a few includes in bma220_spi.c (Jonathan)
> - mention new includes in commit body (Jonathan)
> v4 move some of the changes into precursor patches (01-07) (Andy)
> ---
>  drivers/iio/accel/Kconfig       |   8 +-
>  drivers/iio/accel/Makefile      |   3 +-
>  drivers/iio/accel/bma220.h      |  18 +++
>  drivers/iio/accel/bma220_core.c | 319 ++++++++++++++++++++++++++++++++++++++++
>  drivers/iio/accel/bma220_spi.c  | 314 ++-------------------------------------
>  5 files changed, 357 insertions(+), 305 deletions(-)

> diff --git a/drivers/iio/accel/bma220_core.c b/drivers/iio/accel/bma220_core.c
> new file mode 100644
> index 0000000000000000000000000000000000000000..00fe1064486aa469f7ad15593027c7ec86197365
> --- /dev/null
> +++ b/drivers/iio/accel/bma220_core.c
> @@ -0,0 +1,319 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +/*
> + * BMA220 Digital triaxial acceleration sensor driver
> + *
> + * Copyright (c) 2016,2020 Intel Corporation.
> + */
> +
> +#include <linux/bits.h>

Looks like this needs errno.h as per the one you added to _spi.c below.

> +#include <linux/mod_devicetable.h>
> +#include <linux/module.h>
> +#include <linux/mutex.h>
> +#include <linux/pm.h>
> +#include <linux/types.h>
> +#include <linux/spi/spi.h>
> +
> +#include <linux/iio/buffer.h>
> +#include <linux/iio/iio.h>
> +#include <linux/iio/sysfs.h>
> +#include <linux/iio/trigger_consumer.h>
> +#include <linux/iio/triggered_buffer.h>
> +
> +#include "bma220.h"
> +
> +#define BMA220_REG_ID				0x00
> +#define BMA220_REG_ACCEL_X			0x02
> +#define BMA220_REG_ACCEL_Y			0x03
> +#define BMA220_REG_ACCEL_Z			0x04
> +#define BMA220_REG_RANGE			0x11
> +#define BMA220_REG_SUSPEND			0x18
> +
> +#define BMA220_CHIP_ID				0xDD
> +#define BMA220_READ_MASK			BIT(7)
> +#define BMA220_RANGE_MASK			GENMASK(1, 0)
> +#define BMA220_SUSPEND_SLEEP			0xFF
> +#define BMA220_SUSPEND_WAKE			0x00
> +
> +#define BMA220_DEVICE_NAME			"bma220"
> +
> +#define BMA220_ACCEL_CHANNEL(index, reg, axis) {			\
> +	.type = IIO_ACCEL,						\
> +	.address = reg,							\
> +	.modified = 1,							\
> +	.channel2 = IIO_MOD_##axis,					\
> +	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),			\
> +	.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),		\
> +	.scan_index = index,						\
> +	.scan_type = {							\
> +		.sign = 's',						\
> +		.realbits = 6,						\
> +		.storagebits = 8,					\
> +		.shift = 2,						\
> +		.endianness = IIO_CPU,					\
> +	},								\
> +}
> +
> +enum bma220_axis {
> +	AXIS_X,
> +	AXIS_Y,
> +	AXIS_Z,
> +};
> +
> +static const int bma220_scale_table[][2] = {
> +	{0, 623000}, {1, 248000}, {2, 491000}, {4, 983000},

If you do a white space bracket related separate patch as suggested below
feel free to include this one as:
	{ 0, 623000 }, { 1, 248000 }, { 2, 491000 }, { 4, 983000 },

But don't do it in this split patch.  I don't mind that much if you don't
do it at all.

> +};


> diff --git a/drivers/iio/accel/bma220_spi.c b/drivers/iio/accel/bma220_spi.c
> index abff24a48e5aaa5efb05cdf1924ffea24f4da4c5..70b8bd94895e95936c7294271b5d46d9ec9903c6 100644
> --- a/drivers/iio/accel/bma220_spi.c
> +++ b/drivers/iio/accel/bma220_spi.c
> @@ -5,334 +5,42 @@
>   * Copyright (c) 2016,2020 Intel Corporation.
>   */
>  
> -#include <linux/bits.h>
> +#include <linux/errno.h>

It seems rather unlikely that the split out spi.c file needs this but the previous
more generic one that incorporate pretty much all this code did not.
I checked and it should always have been here so I've added it by tweaking patch 6.


>  #include <linux/mod_devicetable.h>
>  #include <linux/module.h>
> -#include <linux/mutex.h>
> -#include <linux/pm.h>
>  #include <linux/types.h>
>  #include <linux/spi/spi.h>
>  
> -#include <linux/iio/buffer.h>
> -#include <linux/iio/iio.h>
> -#include <linux/iio/sysfs.h>
> -#include <linux/iio/trigger_consumer.h>
> -#include <linux/iio/triggered_buffer.h>
> +#include "bma220.h"

...

> -static int bma220_resume(struct device *dev)
> -{
> -	struct spi_device *spi = to_spi_device(dev);
> -
> -	return bma220_power(spi, true);
> +	return bma220_common_probe(spi);
>  }
> -static DEFINE_SIMPLE_DEV_PM_OPS(bma220_pm_ops, bma220_suspend, bma220_resume);
>  
>  static const struct spi_device_id bma220_spi_id[] = {
> -	{"bma220", 0},
> +	{ "bma220", 0 },

Whist good this is technically an unrelated white space change so
shouldn't really be in this patch.  However if this is only thing that
needs a new spin lets not bother.  Sometimes it's better to just be
a little relaxed on patch split up so we don't waste time on more versions!

>  	{ }
>  };
>  
>  static const struct acpi_device_id bma220_acpi_id[] = {
> -	{"BMA0220", 0},
> +	{ "BMA0220", 0 },
Same here.
>  	{ }
>  };
>  MODULE_DEVICE_TABLE(spi, bma220_spi_id);
>  
> -static struct spi_driver bma220_driver = {
> +static struct spi_driver bma220_spi_driver = {
>  	.driver = {
>  		.name = "bma220_spi",
>  		.pm = pm_sleep_ptr(&bma220_pm_ops),
>  		.acpi_match_table = bma220_acpi_id,
>  	},
> -	.probe =            bma220_probe,
> +	.probe =            bma220_spi_probe,
>  	.id_table =         bma220_spi_id,
>  };
> -module_spi_driver(bma220_driver);
> +module_spi_driver(bma220_spi_driver);
>  
>  MODULE_AUTHOR("Tiberiu Breana <tiberiu.a.breana@intel.com>");
> -MODULE_DESCRIPTION("BMA220 acceleration sensor driver");
> +MODULE_DESCRIPTION("BMA220 triaxial acceleration sensor spi driver");
>  MODULE_LICENSE("GPL");
> +MODULE_IMPORT_NS("IIO_BOSCH_BMA220");
> 

Re: [PATCH v4 07/19] iio: accel: bma220: split original driver

[Petre Rodan]

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Hi Jonathan,

On Sun, Oct 12, 2025 at 03:52:01PM +0100, Jonathan Cameron wrote:
> On Sun, 05 Oct 2025 16:12:16 +0300
> Petre Rodan <petre.rodan@subdimension.ro> wrote:
> 
> > In preparation for the i2c module, move the original code into multiple
> > source files without any other functional change.
> > 
> > Create the additional bma220_core module which currently is not
> > providing an abstracted bus type (this will change with the regmap
> > patch).
> > Fix a few includes in the context of this patch.
> > 
> > Signed-off-by: Petre Rodan <petre.rodan@subdimension.ro>
> 
> It required a bit of hand tweaking after the include tweak I made in the previous patch.
> Also due to comments in here I tweaked a bit more:
> 
> Please check the result on the iio.git / testing branch.

I included two trivial patches in the new series 'bma220 events' that do a
pre-cleanup of this driver.

Thank you everyone for the feedback.

best regards,
peter

[-- Attachment #2: signature.asc --]
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[PATCH v4 08/19] iio: accel: bma220: add open firmware table

[Petre Rodan]

Add open firmware entry to the spi driver.

Signed-off-by: Petre Rodan <petre.rodan@subdimension.ro>
---
v1->v2 split from bigger patch
v3->v4 no change
---
 drivers/iio/accel/bma220_spi.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/drivers/iio/accel/bma220_spi.c b/drivers/iio/accel/bma220_spi.c
index 70b8bd94895e95936c7294271b5d46d9ec9903c6..b27592591d2817e2c3f3780f4307e3a76c7e06cb 100644
--- a/drivers/iio/accel/bma220_spi.c
+++ b/drivers/iio/accel/bma220_spi.c
@@ -29,10 +29,17 @@ static const struct acpi_device_id bma220_acpi_id[] = {
 };
 MODULE_DEVICE_TABLE(spi, bma220_spi_id);
 
+static const struct of_device_id bma220_of_spi_match[] = {
+	{ .compatible = "bosch,bma220" },
+	{ }
+};
+MODULE_DEVICE_TABLE(of, bma220_of_spi_match);
+
 static struct spi_driver bma220_spi_driver = {
 	.driver = {
 		.name = "bma220_spi",
 		.pm = pm_sleep_ptr(&bma220_pm_ops),
+		.of_match_table = bma220_of_spi_match,
 		.acpi_match_table = bma220_acpi_id,
 	},
 	.probe =            bma220_spi_probe,

-- 
2.49.1

Re: [PATCH v4 08/19] iio: accel: bma220: add open firmware table

[Jonathan Cameron]

On Sun, 05 Oct 2025 16:12:17 +0300
Petre Rodan <petre.rodan@subdimension.ro> wrote:

> Add open firmware entry to the spi driver.
> 
> Signed-off-by: Petre Rodan <petre.rodan@subdimension.ro>
> ---
Applied. Thanks!

[PATCH v4 09/19] iio: accel: bma220: turn power supplies on

[Petre Rodan]

Add devm_regulator_bulk_get_enable() to device probe().

Signed-off-by: Petre Rodan <petre.rodan@subdimension.ro>
---
v1->v2 split from larger patch
v2->v3 change commit desc (Jonathan)
v4 dev ptr (Andy)
---
 drivers/iio/accel/bma220_core.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/drivers/iio/accel/bma220_core.c b/drivers/iio/accel/bma220_core.c
index 00fe1064486aa469f7ad15593027c7ec86197365..319a3d6867ee5ac2da64c9baf02a760865302ee8 100644
--- a/drivers/iio/accel/bma220_core.c
+++ b/drivers/iio/accel/bma220_core.c
@@ -10,6 +10,7 @@
 #include <linux/module.h>
 #include <linux/mutex.h>
 #include <linux/pm.h>
+#include <linux/regulator/consumer.h>
 #include <linux/types.h>
 #include <linux/spi/spi.h>
 
@@ -230,6 +231,12 @@ static int bma220_init(struct spi_device *spi)
 {
 	int ret;
 	struct device *dev = &spi->dev;
+	static const char * const regulator_names[] = { "vddd", "vddio", "vdda" };
+
+	ret = devm_regulator_bulk_get_enable(dev, ARRAY_SIZE(regulator_names),
+					     regulator_names);
+	if (ret)
+		return dev_err_probe(dev, ret, "Failed to get regulators\n");
 
 	ret = bma220_read_reg(spi, BMA220_REG_ID);
 	if (ret < 0)

-- 
2.49.1

Re: [PATCH v4 09/19] iio: accel: bma220: turn power supplies on

[Jonathan Cameron]

On Sun, 05 Oct 2025 16:12:18 +0300
Petre Rodan <petre.rodan@subdimension.ro> wrote:

> Add devm_regulator_bulk_get_enable() to device probe().
> 
> Signed-off-by: Petre Rodan <petre.rodan@subdimension.ro>
Applied. Thanks!

[PATCH v4 10/19] iio: accel: bma220: reset registers during init stage

[Petre Rodan]

Bring all configuration registers to default values during
device probe().
Remove trivial code duplication regarding bma220_power() in
_init()

Signed-off-by: Petre Rodan <petre.rodan@subdimension.ro>
---
v4 dev ptr (Andy)
---
 drivers/iio/accel/bma220_core.c | 44 +++++++++++++++++++++++++++++++++--------
 1 file changed, 36 insertions(+), 8 deletions(-)

diff --git a/drivers/iio/accel/bma220_core.c b/drivers/iio/accel/bma220_core.c
index 319a3d6867ee5ac2da64c9baf02a760865302ee8..1b118a9fce3f16f0cd805a68b9887c6eaf24973a 100644
--- a/drivers/iio/accel/bma220_core.c
+++ b/drivers/iio/accel/bma220_core.c
@@ -28,12 +28,15 @@
 #define BMA220_REG_ACCEL_Z			0x04
 #define BMA220_REG_RANGE			0x11
 #define BMA220_REG_SUSPEND			0x18
+#define BMA220_REG_SOFTRESET			0x19
 
 #define BMA220_CHIP_ID				0xDD
 #define BMA220_READ_MASK			BIT(7)
 #define BMA220_RANGE_MASK			GENMASK(1, 0)
 #define BMA220_SUSPEND_SLEEP			0xFF
 #define BMA220_SUSPEND_WAKE			0x00
+#define BMA220_RESET_MODE			0xFF
+#define BMA220_NONRESET_MODE			0x00
 
 #define BMA220_DEVICE_NAME			"bma220"
 
@@ -202,6 +205,31 @@ static const struct iio_info bma220_info = {
 	.read_avail		= bma220_read_avail,
 };
 
+static int bma220_reset(struct spi_device *spi, bool up)
+{
+	int ret;
+	unsigned int i;
+
+	/*
+	 * The chip can be reset by a simple register read.
+	 * We need up to 2 register reads of the softreset register
+	 * to make sure that the device is in the desired state.
+	 */
+	for (i = 0; i < 2; i++) {
+		ret = bma220_read_reg(spi, BMA220_REG_SOFTRESET);
+		if (ret < 0)
+			return ret;
+
+		if (up && ret == BMA220_RESET_MODE)
+			return 0;
+
+		if (!up && ret == BMA220_NONRESET_MODE)
+			return 0;
+	}
+
+	return -EBUSY;
+}
+
 static int bma220_power(struct spi_device *spi, bool up)
 {
 	int ret;
@@ -246,14 +274,14 @@ static int bma220_init(struct spi_device *spi)
 	if (ret != BMA220_CHIP_ID)
 		dev_info(dev, "Unknown chip found: 0x%02x\n", ret);
 
-	/* Make sure the chip is powered on */
-	ret = bma220_read_reg(spi, BMA220_REG_SUSPEND);
-	if (ret == BMA220_SUSPEND_WAKE)
-		ret = bma220_read_reg(spi, BMA220_REG_SUSPEND);
-	if (ret < 0)
-		return ret;
-	if (ret == BMA220_SUSPEND_WAKE)
-		return -EBUSY;
+	/* Make sure the chip is powered on and config registers are reset */
+	ret = bma220_power(spi, true);
+	if (ret)
+		return dev_err_probe(dev, ret, "Failed to power-on chip\n");
+
+	ret = bma220_reset(spi, true);
+	if (ret)
+		return dev_err_probe(dev, ret, "Failed to soft reset chip\n");
 
 	return 0;
 }

-- 
2.49.1

Re: [PATCH v4 10/19] iio: accel: bma220: reset registers during init stage

[Jonathan Cameron]

On Sun, 05 Oct 2025 16:12:19 +0300
Petre Rodan <petre.rodan@subdimension.ro> wrote:

> Bring all configuration registers to default values during
> device probe().
> Remove trivial code duplication regarding bma220_power() in
> _init()
> 
> Signed-off-by: Petre Rodan <petre.rodan@subdimension.ro>
Applied.

[PATCH v4 11/19] iio: accel: bma220: migrate to regmap API

[Petre Rodan]

Switch to regmap API.

Signed-off-by: Petre Rodan <petre.rodan@subdimension.ro>
---
v1->v2
- split out into more patches (Jonathan)
v2->v3
- split out into even more patches (Jonathan)
- use dev_err_probe() (Jonathan)
v4 remove dev from priv struct (Andy)
---
 drivers/iio/accel/Kconfig       |   2 +
 drivers/iio/accel/bma220.h      |   7 +-
 drivers/iio/accel/bma220_core.c | 231 +++++++++++++++++++++++++++-------------
 drivers/iio/accel/bma220_spi.c  |  10 +-
 4 files changed, 173 insertions(+), 77 deletions(-)

diff --git a/drivers/iio/accel/Kconfig b/drivers/iio/accel/Kconfig
index 4648be329917a3054615ed324156d67f53baefb6..988fe4b1f9a52c2e671ea30d8590f25ee1685ac7 100644
--- a/drivers/iio/accel/Kconfig
+++ b/drivers/iio/accel/Kconfig
@@ -219,6 +219,7 @@ config BMA180
 config BMA220
 	tristate "Bosch BMA220 3-Axis Accelerometer Driver"
 	depends on SPI
+	select REGMAP
 	select IIO_BUFFER
 	select IIO_TRIGGERED_BUFFER
 	select BMA220_SPI if SPI
@@ -232,6 +233,7 @@ config BMA220
 
 config BMA220_SPI
 	tristate
+	select REGMAP_SPI
 	depends on BMA220
 
 config BMA400
diff --git a/drivers/iio/accel/bma220.h b/drivers/iio/accel/bma220.h
index dea34244b4fc4971841dc60d79db6c7db27bea20..695f491bc5a03008f26fe8602ba633456159fb1d 100644
--- a/drivers/iio/accel/bma220.h
+++ b/drivers/iio/accel/bma220.h
@@ -9,10 +9,13 @@
 #define _BMA220_H
 
 #include <linux/pm.h>
+#include <linux/regmap.h>
 
+struct device;
+
+extern const struct regmap_config bma220_spi_regmap_config;
 extern const struct dev_pm_ops bma220_pm_ops;
-struct spi_device;
 
-int bma220_common_probe(struct spi_device *dev);
+int bma220_common_probe(struct device *dev, struct regmap *regmap, int irq);
 
 #endif
diff --git a/drivers/iio/accel/bma220_core.c b/drivers/iio/accel/bma220_core.c
index 1b118a9fce3f16f0cd805a68b9887c6eaf24973a..7b1e87c6932a3a6698651e528fb8182c03a2432e 100644
--- a/drivers/iio/accel/bma220_core.c
+++ b/drivers/iio/accel/bma220_core.c
@@ -3,16 +3,20 @@
  * BMA220 Digital triaxial acceleration sensor driver
  *
  * Copyright (c) 2016,2020 Intel Corporation.
+ * Copyright (c) 2025 Petre Rodan  <petre.rodan@subdimension.ro>
  */
 
 #include <linux/bits.h>
+#include <linux/bitfield.h>
+#include <linux/cleanup.h>
+#include <linux/device.h>
 #include <linux/mod_devicetable.h>
 #include <linux/module.h>
 #include <linux/mutex.h>
 #include <linux/pm.h>
+#include <linux/regmap.h>
 #include <linux/regulator/consumer.h>
 #include <linux/types.h>
-#include <linux/spi/spi.h>
 
 #include <linux/iio/buffer.h>
 #include <linux/iio/iio.h>
@@ -23,16 +27,63 @@
 #include "bma220.h"
 
 #define BMA220_REG_ID				0x00
+#define BMA220_REG_REVISION_ID			0x01
 #define BMA220_REG_ACCEL_X			0x02
 #define BMA220_REG_ACCEL_Y			0x03
 #define BMA220_REG_ACCEL_Z			0x04
+#define BMA220_REG_CONF0			0x05
+#define BMA220_HIGH_DUR_MSK			GENMASK(5, 0)
+#define BMA220_HIGH_HY_MSK			GENMASK(7, 6)
+#define BMA220_REG_CONF1			0x06
+#define BMA220_HIGH_TH_MSK			GENMASK(3, 0)
+#define BMA220_LOW_TH_MSK			GENMASK(7, 4)
+#define BMA220_REG_CONF2			0x07
+#define BMA220_LOW_DUR_MSK			GENMASK(5, 0)
+#define BMA220_LOW_HY_MSK			GENMASK(7, 6)
+#define BMA220_REG_CONF3			0x08
+#define BMA220_TT_DUR_MSK			GENMASK(2, 0)
+#define BMA220_TT_TH_MSK			GENMASK(6, 3)
+#define BMA220_REG_CONF4			0x09
+#define BMA220_SLOPE_DUR_MSK			GENMASK(1, 0)
+#define BMA220_SLOPE_TH_MSK			GENMASK(5, 2)
+#define BMA220_REG_CONF5			0x0a
+#define BMA220_TIP_EN_MSK			BIT(4)
+#define BMA220_REG_IF0				0x0b
+#define BMA220_REG_IF1				0x0c
+#define BMA220_IF_SLOPE				BIT(0)
+#define BMA220_IF_DRDY				BIT(1)
+#define BMA220_IF_HIGH				BIT(2)
+#define BMA220_IF_LOW				BIT(3)
+#define BMA220_IF_TT				BIT(4)
+#define BMA220_REG_IE0				0x0d
+#define BMA220_INT_EN_TAP_Z_MSK			BIT(0)
+#define BMA220_INT_EN_TAP_Y_MSK			BIT(1)
+#define BMA220_INT_EN_TAP_X_MSK			BIT(2)
+#define BMA220_INT_EN_SLOPE_Z_MSK		BIT(3)
+#define BMA220_INT_EN_SLOPE_Y_MSK		BIT(4)
+#define BMA220_INT_EN_SLOPE_X_MSK		BIT(5)
+#define BMA220_INT_EN_DRDY_MSK			BIT(7)
+#define BMA220_REG_IE1				0x0e
+#define BMA220_INT_EN_HIGH_Z_MSK		BIT(0)
+#define BMA220_INT_EN_HIGH_Y_MSK		BIT(1)
+#define BMA220_INT_EN_HIGH_X_MSK		BIT(2)
+#define BMA220_INT_EN_LOW_MSK			BIT(3)
+#define BMA220_INT_LATCH_MSK			GENMASK(6, 4)
+#define BMA220_INT_RST_MSK			BIT(7)
+#define BMA220_REG_IE2				0x0f
+#define BMA220_REG_FILTER			0x10
+#define BMA220_FILTER_MASK			GENMASK(3, 0)
 #define BMA220_REG_RANGE			0x11
+#define BMA220_RANGE_MASK			GENMASK(1, 0)
+#define BMA220_REG_WDT				0x17
+#define BMA220_WDT_MASK				GENMASK(2, 1)
+#define BMA220_WDT_OFF				0x0
+#define BMA220_WDT_1MS				0x2
+#define BMA220_WDT_10MS				0x3
 #define BMA220_REG_SUSPEND			0x18
 #define BMA220_REG_SOFTRESET			0x19
 
 #define BMA220_CHIP_ID				0xDD
-#define BMA220_READ_MASK			BIT(7)
-#define BMA220_RANGE_MASK			GENMASK(1, 0)
 #define BMA220_SUSPEND_SLEEP			0xFF
 #define BMA220_SUSPEND_WAKE			0x00
 #define BMA220_RESET_MODE			0xFF
@@ -68,14 +119,14 @@ static const int bma220_scale_table[][2] = {
 };
 
 struct bma220_data {
-	struct spi_device *spi_device;
+	struct regmap *regmap;
 	struct mutex lock;
+	u8 range_idx;
 	struct {
 		s8 chans[3];
 		/* Ensure timestamp is naturally aligned. */
 		aligned_s64 timestamp;
-	} scan;
-	u8 tx_buf[2] __aligned(IIO_DMA_MINALIGN);
+	} scan __aligned(IIO_DMA_MINALIGN);
 };
 
 static const struct iio_chan_spec bma220_channels[] = {
@@ -85,35 +136,57 @@ static const struct iio_chan_spec bma220_channels[] = {
 	IIO_CHAN_SOFT_TIMESTAMP(3),
 };
 
-static inline int bma220_read_reg(struct spi_device *spi, u8 reg)
-{
-	return spi_w8r8(spi, reg | BMA220_READ_MASK);
-}
-
 static const unsigned long bma220_accel_scan_masks[] = {
 	BIT(AXIS_X) | BIT(AXIS_Y) | BIT(AXIS_Z),
 	0
 };
 
+static bool bma220_is_writable_reg(struct device *dev, unsigned int reg)
+{
+	switch (reg) {
+	case BMA220_REG_CONF0:
+	case BMA220_REG_CONF1:
+	case BMA220_REG_CONF2:
+	case BMA220_REG_CONF3:
+	case BMA220_REG_CONF4:
+	case BMA220_REG_CONF5:
+	case BMA220_REG_IE0:
+	case BMA220_REG_IE1:
+	case BMA220_REG_IE2:
+	case BMA220_REG_FILTER:
+	case BMA220_REG_RANGE:
+	case BMA220_REG_WDT:
+		return true;
+	default:
+		return false;
+	}
+}
+
+const struct regmap_config bma220_spi_regmap_config = {
+	.reg_bits = 8,
+	.val_bits = 8,
+	.read_flag_mask = BIT(7),
+	.max_register = BMA220_REG_SOFTRESET,
+	.cache_type = REGCACHE_NONE,
+	.writeable_reg = bma220_is_writable_reg,
+};
+EXPORT_SYMBOL_NS_GPL(bma220_spi_regmap_config, "IIO_BOSCH_BMA220");
+
 static irqreturn_t bma220_trigger_handler(int irq, void *p)
 {
 	int ret;
 	struct iio_poll_func *pf = p;
 	struct iio_dev *indio_dev = pf->indio_dev;
 	struct bma220_data *data = iio_priv(indio_dev);
-	struct spi_device *spi = data->spi_device;
 
-	mutex_lock(&data->lock);
-	data->tx_buf[0] = BMA220_REG_ACCEL_X | BMA220_READ_MASK;
-	ret = spi_write_then_read(spi, data->tx_buf, 1, &data->scan.chans,
-				  ARRAY_SIZE(bma220_channels) - 1);
+	ret = regmap_bulk_read(data->regmap, BMA220_REG_ACCEL_X,
+			       &data->scan.chans,
+			       sizeof(data->scan.chans));
 	if (ret < 0)
-		goto err;
+		return IRQ_NONE;
 
 	iio_push_to_buffers_with_ts(indio_dev, &data->scan, sizeof(data->scan),
 				    pf->timestamp);
-err:
-	mutex_unlock(&data->lock);
 	iio_trigger_notify_done(indio_dev->trig);
 
 	return IRQ_HANDLED;
@@ -124,24 +197,24 @@ static int bma220_read_raw(struct iio_dev *indio_dev,
 			   int *val, int *val2, long mask)
 {
 	int ret;
-	u8 range_idx;
+	u8 index;
+	unsigned int reg;
 	struct bma220_data *data = iio_priv(indio_dev);
 
+	guard(mutex)(&data->lock);
+
 	switch (mask) {
 	case IIO_CHAN_INFO_RAW:
-		ret = bma220_read_reg(data->spi_device, chan->address);
+		ret = regmap_read(data->regmap, chan->address, &reg);
 		if (ret < 0)
 			return -EINVAL;
-		*val = sign_extend32(ret >> chan->scan_type.shift,
+		*val = sign_extend32(reg >> chan->scan_type.shift,
 				     chan->scan_type.realbits - 1);
 		return IIO_VAL_INT;
 	case IIO_CHAN_INFO_SCALE:
-		ret = bma220_read_reg(data->spi_device, BMA220_REG_RANGE);
-		if (ret < 0)
-			return ret;
-		range_idx = ret & BMA220_RANGE_MASK;
-		*val = bma220_scale_table[range_idx][0];
-		*val2 = bma220_scale_table[range_idx][1];
+		index = data->range_idx;
+		*val = bma220_scale_table[index][0];
+		*val2 = bma220_scale_table[index][1];
 		return IIO_VAL_INT_PLUS_MICRO;
 	}
 
@@ -157,6 +230,8 @@ static int bma220_write_raw(struct iio_dev *indio_dev,
 	int index = -1;
 	struct bma220_data *data = iio_priv(indio_dev);
 
+	guard(mutex)(&data->lock);
+
 	switch (mask) {
 	case IIO_CHAN_INFO_SCALE:
 		for (i = 0; i < ARRAY_SIZE(bma220_scale_table); i++)
@@ -168,14 +243,12 @@ static int bma220_write_raw(struct iio_dev *indio_dev,
 		if (index < 0)
 			return -EINVAL;
 
-		mutex_lock(&data->lock);
-		data->tx_buf[0] = BMA220_REG_RANGE;
-		data->tx_buf[1] = index;
-		ret = spi_write(data->spi_device, data->tx_buf,
-				sizeof(data->tx_buf));
+		ret = regmap_update_bits(data->regmap, BMA220_REG_RANGE,
+					 BMA220_RANGE_MASK,
+					 FIELD_PREP(BMA220_RANGE_MASK, index));
 		if (ret < 0)
 			return ret;
-		mutex_unlock(&data->lock);
+		data->range_idx = index;
 
 		return 0;
 	}
@@ -205,10 +278,10 @@ static const struct iio_info bma220_info = {
 	.read_avail		= bma220_read_avail,
 };
 
-static int bma220_reset(struct spi_device *spi, bool up)
+static int bma220_reset(struct bma220_data *data, bool up)
 {
 	int ret;
-	unsigned int i;
+	unsigned int i, val;
 
 	/*
 	 * The chip can be reset by a simple register read.
@@ -216,24 +289,24 @@ static int bma220_reset(struct spi_device *spi, bool up)
 	 * to make sure that the device is in the desired state.
 	 */
 	for (i = 0; i < 2; i++) {
-		ret = bma220_read_reg(spi, BMA220_REG_SOFTRESET);
+		ret = regmap_read(data->regmap, BMA220_REG_SOFTRESET, &val);
 		if (ret < 0)
 			return ret;
 
-		if (up && ret == BMA220_RESET_MODE)
+		if (up && val == BMA220_RESET_MODE)
 			return 0;
 
-		if (!up && ret == BMA220_NONRESET_MODE)
+		if (!up && val == BMA220_NONRESET_MODE)
 			return 0;
 	}
 
 	return -EBUSY;
 }
 
-static int bma220_power(struct spi_device *spi, bool up)
+static int bma220_power(struct bma220_data *data, bool up)
 {
 	int ret;
-	unsigned int i;
+	unsigned int i, val;
 
 	/*
 	 * The chip can be suspended/woken up by a simple register read.
@@ -241,70 +314,84 @@ static int bma220_power(struct spi_device *spi, bool up)
 	 * to make sure that the device is in the desired state.
 	 */
 	for (i = 0; i < 2; i++) {
-		ret = bma220_read_reg(spi, BMA220_REG_SUSPEND);
+		ret = regmap_read(data->regmap, BMA220_REG_SUSPEND, &val);
 		if (ret < 0)
 			return ret;
 
-		if (up && ret == BMA220_SUSPEND_SLEEP)
+		if (up && val == BMA220_SUSPEND_SLEEP)
 			return 0;
 
-		if (!up && ret == BMA220_SUSPEND_WAKE)
+		if (!up && val == BMA220_SUSPEND_WAKE)
 			return 0;
 	}
 
 	return -EBUSY;
 }
 
-static int bma220_init(struct spi_device *spi)
+static int bma220_init(struct device *dev, struct bma220_data *data)
 {
 	int ret;
-	struct device *dev = &spi->dev;
+	unsigned int val;
 	static const char * const regulator_names[] = { "vddd", "vddio", "vdda" };
 
-	ret = devm_regulator_bulk_get_enable(dev, ARRAY_SIZE(regulator_names),
+	ret = devm_regulator_bulk_get_enable(dev,
+					     ARRAY_SIZE(regulator_names),
 					     regulator_names);
 	if (ret)
 		return dev_err_probe(dev, ret, "Failed to get regulators\n");
 
-	ret = bma220_read_reg(spi, BMA220_REG_ID);
-	if (ret < 0)
+	ret = regmap_read(data->regmap, BMA220_REG_ID, &val);
+	if (ret)
 		return dev_err_probe(dev, ret,
 				     "Failed to read chip id register\n");
 
-	if (ret != BMA220_CHIP_ID)
-		dev_info(dev, "Unknown chip found: 0x%02x\n", ret);
+	if (val != BMA220_CHIP_ID)
+		dev_info(dev, "Unknown chip found: 0x%02x\n", val);
 
-	/* Make sure the chip is powered on and config registers are reset */
-	ret = bma220_power(spi, true);
+	ret = bma220_power(data, true);
 	if (ret)
 		return dev_err_probe(dev, ret, "Failed to power-on chip\n");
 
-	ret = bma220_reset(spi, true);
+	ret = bma220_reset(data, true);
 	if (ret)
 		return dev_err_probe(dev, ret, "Failed to soft reset chip\n");
 
 	return 0;
 }
 
-static void bma220_deinit(void *spi)
+static void bma220_deinit(void *data_ptr)
 {
-	bma220_power(spi, false);
+	struct bma220_data *data = data_ptr;
+	int ret;
+	struct device *dev = regmap_get_device(data->regmap);
+
+	ret = bma220_power(data, false);
+	if (ret)
+		dev_warn(dev,
+			 "Failed to put device into suspend mode (%pe)\n",
+			 ERR_PTR(ret));
 }
 
-int bma220_common_probe(struct spi_device *spi)
+int bma220_common_probe(struct device *dev, struct regmap *regmap, int irq)
 {
 	int ret;
 	struct iio_dev *indio_dev;
 	struct bma220_data *data;
-	struct device *dev = &spi->dev;
 
 	indio_dev = devm_iio_device_alloc(dev, sizeof(*data));
 	if (!indio_dev)
 		return -ENOMEM;
 
 	data = iio_priv(indio_dev);
-	data->spi_device = spi;
-	mutex_init(&data->lock);
+	data->regmap = regmap;
+
+	ret = bma220_init(dev, data);
+	if (ret)
+		return ret;
+
+	ret = devm_mutex_init(dev, &data->lock);
+	if (ret)
+		return ret;
 
 	indio_dev->info = &bma220_info;
 	indio_dev->name = BMA220_DEVICE_NAME;
@@ -313,38 +400,34 @@ int bma220_common_probe(struct spi_device *spi)
 	indio_dev->num_channels = ARRAY_SIZE(bma220_channels);
 	indio_dev->available_scan_masks = bma220_accel_scan_masks;
 
-	ret = bma220_init(data->spi_device);
-	if (ret)
-		return ret;
-
-	ret = devm_add_action_or_reset(dev, bma220_deinit, spi);
+	ret = devm_add_action_or_reset(dev, bma220_deinit, data);
 	if (ret)
 		return ret;
 
 	ret = devm_iio_triggered_buffer_setup(dev, indio_dev,
 					      iio_pollfunc_store_time,
 					      bma220_trigger_handler, NULL);
-	if (ret < 0) {
-		dev_err(dev, "iio triggered buffer setup failed\n");
-		return ret;
-	}
+	if (ret < 0)
+		dev_err_probe(dev, ret, "iio triggered buffer setup failed\n");
 
 	return devm_iio_device_register(dev, indio_dev);
 }
-EXPORT_SYMBOL_NS(bma220_common_probe, "IIO_BOSCH_BMA220");
+EXPORT_SYMBOL_NS_GPL(bma220_common_probe, "IIO_BOSCH_BMA220");
 
 static int bma220_suspend(struct device *dev)
 {
-	struct spi_device *spi = to_spi_device(dev);
+	struct iio_dev *indio_dev = dev_get_drvdata(dev);
+	struct bma220_data *data = iio_priv(indio_dev);
 
-	return bma220_power(spi, false);
+	return bma220_power(data, false);
 }
 
 static int bma220_resume(struct device *dev)
 {
-	struct spi_device *spi = to_spi_device(dev);
+	struct iio_dev *indio_dev = dev_get_drvdata(dev);
+	struct bma220_data *data = iio_priv(indio_dev);
 
-	return bma220_power(spi, true);
+	return bma220_power(data, true);
 }
 EXPORT_NS_SIMPLE_DEV_PM_OPS(bma220_pm_ops, bma220_suspend, bma220_resume,
 			    IIO_BOSCH_BMA220);
diff --git a/drivers/iio/accel/bma220_spi.c b/drivers/iio/accel/bma220_spi.c
index b27592591d2817e2c3f3780f4307e3a76c7e06cb..8990155ac0cd36ace08d1192b4dda3c275ad675e 100644
--- a/drivers/iio/accel/bma220_spi.c
+++ b/drivers/iio/accel/bma220_spi.c
@@ -8,6 +8,7 @@
 #include <linux/errno.h>
 #include <linux/mod_devicetable.h>
 #include <linux/module.h>
+#include <linux/regmap.h>
 #include <linux/types.h>
 #include <linux/spi/spi.h>
 
@@ -15,7 +16,14 @@
 
 static int bma220_spi_probe(struct spi_device *spi)
 {
-	return bma220_common_probe(spi);
+	struct regmap *regmap;
+
+	regmap = devm_regmap_init_spi(spi, &bma220_spi_regmap_config);
+	if (IS_ERR(regmap))
+		return dev_err_probe(&spi->dev, PTR_ERR(regmap),
+				     "failed to create regmap\n");
+
+	return bma220_common_probe(&spi->dev, regmap, spi->irq);
 }
 
 static const struct spi_device_id bma220_spi_id[] = {

-- 
2.49.1

Re: [PATCH v4 11/19] iio: accel: bma220: migrate to regmap API

[Jonathan Cameron]

On Sun, 05 Oct 2025 16:12:20 +0300
Petre Rodan <petre.rodan@subdimension.ro> wrote:

> Switch to regmap API.
> 
> Signed-off-by: Petre Rodan <petre.rodan@subdimension.ro>
This took a bit of hand applying due to my messing around
with headers in earlier patches. Please check I didn't mess it up!

Applied.

Thanks,

Jonathan

[PATCH v4 12/19] iio: accel: bma220: populate buffer ts in trigger handler

[Petre Rodan]

Populate buffer timestamps in trigger handler since not all
triggers can run the top half handler that provides
pf->timestamp.

Fixes failing unit test that triggers based on the INT signal.

Signed-off-by: Petre Rodan <petre.rodan@subdimension.ro>
---
v2->v3 split out from bigger patch (Jonathan)
v4 more verbose commit msg (Jonathan)
---
 drivers/iio/accel/bma220_core.c | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/drivers/iio/accel/bma220_core.c b/drivers/iio/accel/bma220_core.c
index 7b1e87c6932a3a6698651e528fb8182c03a2432e..ec7409db83f81882043653cd70e3205500348994 100644
--- a/drivers/iio/accel/bma220_core.c
+++ b/drivers/iio/accel/bma220_core.c
@@ -186,7 +186,7 @@ static irqreturn_t bma220_trigger_handler(int irq, void *p)
 		return IRQ_NONE;
 
 	iio_push_to_buffers_with_ts(indio_dev, &data->scan, sizeof(data->scan),
-				    pf->timestamp);
+				    iio_get_time_ns(indio_dev));
 	iio_trigger_notify_done(indio_dev->trig);
 
 	return IRQ_HANDLED;
@@ -404,8 +404,7 @@ int bma220_common_probe(struct device *dev, struct regmap *regmap, int irq)
 	if (ret)
 		return ret;
 
-	ret = devm_iio_triggered_buffer_setup(dev, indio_dev,
-					      iio_pollfunc_store_time,
+	ret = devm_iio_triggered_buffer_setup(dev, indio_dev, NULL,
 					      bma220_trigger_handler, NULL);
 	if (ret < 0)
 		dev_err_probe(dev, ret, "iio triggered buffer setup failed\n");

-- 
2.49.1

Re: [PATCH v4 12/19] iio: accel: bma220: populate buffer ts in trigger handler

[Jonathan Cameron]

On Sun, 05 Oct 2025 16:12:21 +0300
Petre Rodan <petre.rodan@subdimension.ro> wrote:

> Populate buffer timestamps in trigger handler since not all
> triggers can run the top half handler that provides
> pf->timestamp.
> 
> Fixes failing unit test that triggers based on the INT signal.
> 
> Signed-off-by: Petre Rodan <petre.rodan@subdimension.ro>
I hope that we will at somepoint get the generic code that would make this unnecessary
but it's not there yet so fair enough.

Applied.

Re: [PATCH v4 12/19] iio: accel: bma220: populate buffer ts in trigger handler

[Petre Rodan]

[-- Attachment #1: Type: text/plain, Size: 505 bytes --]


Hello Jonathan.

I was a bit worried and I hope you've fully recovered from the flu.

And yes, it also had to restart the rebase multiple times because either I forgot to add bma220.h or I tweaked a few innocent lines in the 4-th patch and they had a ripple effect on everything that followed. Thank you for adding the finishing touches.

> Applied.

I promise to test these out quickly, but please do a push on your testing branch (the last commit I can see is the previous patch).

best regards,
peter

[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 833 bytes --]

[PATCH v4 13/19] iio: accel: bma220: use find_match_table fct

[Petre Rodan]

Clean up the code a bit by using a find_match_table function.

Signed-off-by: Petre Rodan <petre.rodan@subdimension.ro>
---
v2->v3 split out from bigger patch (Jonathan)
v4 no change
---
 drivers/iio/accel/bma220_core.c | 23 ++++++++++++++++-------
 1 file changed, 16 insertions(+), 7 deletions(-)

diff --git a/drivers/iio/accel/bma220_core.c b/drivers/iio/accel/bma220_core.c
index ec7409db83f81882043653cd70e3205500348994..42d5acce0a8387734d932c77fec9777a7a01f774 100644
--- a/drivers/iio/accel/bma220_core.c
+++ b/drivers/iio/accel/bma220_core.c
@@ -221,11 +221,23 @@ static int bma220_read_raw(struct iio_dev *indio_dev,
 	return -EINVAL;
 }
 
+static int bma220_find_match_2dt(const int (*tbl)[2], const int n,
+				 const int val, const int val2)
+{
+	int i;
+
+	for (i = 0; i < n; i++) {
+		if (tbl[i][0] == val && tbl[i][1] == val2)
+			return i;
+	}
+
+	return -EINVAL;
+}
+
 static int bma220_write_raw(struct iio_dev *indio_dev,
 			    struct iio_chan_spec const *chan,
 			    int val, int val2, long mask)
 {
-	int i;
 	int ret;
 	int index = -1;
 	struct bma220_data *data = iio_priv(indio_dev);
@@ -234,12 +246,9 @@ static int bma220_write_raw(struct iio_dev *indio_dev,
 
 	switch (mask) {
 	case IIO_CHAN_INFO_SCALE:
-		for (i = 0; i < ARRAY_SIZE(bma220_scale_table); i++)
-			if (val == bma220_scale_table[i][0] &&
-			    val2 == bma220_scale_table[i][1]) {
-				index = i;
-				break;
-			}
+		index = bma220_find_match_2dt(bma220_scale_table,
+					      ARRAY_SIZE(bma220_scale_table),
+					      val, val2);
 		if (index < 0)
 			return -EINVAL;
 

-- 
2.49.1

Re: [PATCH v4 13/19] iio: accel: bma220: use find_match_table fct

[Jonathan Cameron]

On Sun, 05 Oct 2025 16:12:22 +0300
Petre Rodan <petre.rodan@subdimension.ro> wrote:

> Clean up the code a bit by using a find_match_table function.
> 
> Signed-off-by: Petre Rodan <petre.rodan@subdimension.ro>
Applied. Thanks!

[PATCH v4 14/19] iio: accel: bma220: add i2c module

[Petre Rodan]

Add the bma220_i2c module.

Note that this kernel module transparently shifts all register addresses
1 bit to the left, so all functions will operate based on the SPI memory
map.

Signed-off-by: Petre Rodan <petre.rodan@subdimension.ro>
---
v1->v2 no change
v2->v3
- depends I2C || SPI (David)
- change extern const struct order (David)
- remove unused includes (David)
v4 no change
---
 drivers/iio/accel/Kconfig       | 11 ++++++--
 drivers/iio/accel/Makefile      |  1 +
 drivers/iio/accel/bma220.h      |  1 +
 drivers/iio/accel/bma220_core.c | 18 +++++++++++++
 drivers/iio/accel/bma220_i2c.c  | 58 +++++++++++++++++++++++++++++++++++++++++
 5 files changed, 87 insertions(+), 2 deletions(-)

diff --git a/drivers/iio/accel/Kconfig b/drivers/iio/accel/Kconfig
index 988fe4b1f9a52c2e671ea30d8590f25ee1685ac7..76911278fb217bd3e429c427b873fb7eae26420e 100644
--- a/drivers/iio/accel/Kconfig
+++ b/drivers/iio/accel/Kconfig
@@ -218,10 +218,11 @@ config BMA180
 
 config BMA220
 	tristate "Bosch BMA220 3-Axis Accelerometer Driver"
-	depends on SPI
+	depends on I2C || SPI
 	select REGMAP
 	select IIO_BUFFER
 	select IIO_TRIGGERED_BUFFER
+	select BMA220_I2C if I2C
 	select BMA220_SPI if SPI
 	help
 	  Say yes here to add support for the Bosch BMA220 triaxial
@@ -229,7 +230,13 @@ config BMA220
 
 	  To compile this driver as a module, choose M here: the
 	  module will be called bma220_core and you will also get
-	  bma220_spi if SPI is enabled.
+	  bma220_i2c if I2C is enabled and bma220_spi if SPI is
+	  enabled.
+
+config BMA220_I2C
+	tristate
+	select REGMAP_I2C
+	depends on BMA220
 
 config BMA220_SPI
 	tristate
diff --git a/drivers/iio/accel/Makefile b/drivers/iio/accel/Makefile
index 56a9f848f7f913633bc2a628c1ac5c9190774b9d..fa440a85928398fee927081f605595ba9fbc4ad9 100644
--- a/drivers/iio/accel/Makefile
+++ b/drivers/iio/accel/Makefile
@@ -26,6 +26,7 @@ obj-$(CONFIG_ADXL380_I2C) += adxl380_i2c.o
 obj-$(CONFIG_ADXL380_SPI) += adxl380_spi.o
 obj-$(CONFIG_BMA180) += bma180.o
 obj-$(CONFIG_BMA220) += bma220_core.o
+obj-$(CONFIG_BMA220_I2C) += bma220_i2c.o
 obj-$(CONFIG_BMA220_SPI) += bma220_spi.o
 obj-$(CONFIG_BMA400) += bma400_core.o
 obj-$(CONFIG_BMA400_I2C) += bma400_i2c.o
diff --git a/drivers/iio/accel/bma220.h b/drivers/iio/accel/bma220.h
index 695f491bc5a03008f26fe8602ba633456159fb1d..e53ca63de54b4e81df0908b11d0fb7f03a86dbdc 100644
--- a/drivers/iio/accel/bma220.h
+++ b/drivers/iio/accel/bma220.h
@@ -13,6 +13,7 @@
 
 struct device;
 
+extern const struct regmap_config bma220_i2c_regmap_config;
 extern const struct regmap_config bma220_spi_regmap_config;
 extern const struct dev_pm_ops bma220_pm_ops;
 
diff --git a/drivers/iio/accel/bma220_core.c b/drivers/iio/accel/bma220_core.c
index 42d5acce0a8387734d932c77fec9777a7a01f774..a3faf1f5ec6d79f2c6105697b404d6eb1f4501db 100644
--- a/drivers/iio/accel/bma220_core.c
+++ b/drivers/iio/accel/bma220_core.c
@@ -172,6 +172,24 @@ const struct regmap_config bma220_spi_regmap_config = {
 };
 EXPORT_SYMBOL_NS_GPL(bma220_spi_regmap_config, "IIO_BOSCH_BMA220");
 
+/*
+ * Based on the datasheet the memory map differs between the SPI and the I2C
+ * implementations. I2C register addresses are simply shifted to the left
+ * by 1 bit yet the register size remains unchanged.
+ * This driver employs the SPI memory map to correlate register names to
+ * addresses regardless of the bus type.
+ */
+
+const struct regmap_config bma220_i2c_regmap_config = {
+	.reg_bits = 8,
+	.val_bits = 8,
+	.reg_shift = -1,
+	.max_register = BMA220_REG_SOFTRESET,
+	.cache_type = REGCACHE_NONE,
+	.writeable_reg = bma220_is_writable_reg,
+};
+EXPORT_SYMBOL_NS_GPL(bma220_i2c_regmap_config, "IIO_BOSCH_BMA220");
+
 static irqreturn_t bma220_trigger_handler(int irq, void *p)
 {
 	int ret;
diff --git a/drivers/iio/accel/bma220_i2c.c b/drivers/iio/accel/bma220_i2c.c
new file mode 100644
index 0000000000000000000000000000000000000000..5dc7c38f53b3173ff43ca29b63132ec44e672cde
--- /dev/null
+++ b/drivers/iio/accel/bma220_i2c.c
@@ -0,0 +1,58 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Bosch triaxial acceleration sensor
+ *
+ * Copyright (c) 2025 Petre Rodan <petre.rodan@subdimension.ro>
+ *
+ * Datasheet: https://media.digikey.com/pdf/Data%20Sheets/Bosch/BMA220.pdf
+ * I2C address is either 0x0b or 0x0a depending on CSB (pin 10)
+ */
+
+#include <linux/errno.h>
+#include <linux/i2c.h>
+#include <linux/mod_devicetable.h>
+#include <linux/module.h>
+#include <linux/regmap.h>
+#include <linux/types.h>
+
+#include "bma220.h"
+
+static int bma220_i2c_probe(struct i2c_client *client)
+{
+	struct regmap *regmap;
+
+	regmap = devm_regmap_init_i2c(client, &bma220_i2c_regmap_config);
+	if (IS_ERR(regmap))
+		return dev_err_probe(&client->dev, PTR_ERR(regmap),
+				     "failed to create regmap\n");
+
+	return bma220_common_probe(&client->dev, regmap, client->irq);
+}
+
+static const struct of_device_id bma220_i2c_match[] = {
+	{ .compatible = "bosch,bma220" },
+	{ }
+};
+MODULE_DEVICE_TABLE(of, bma220_i2c_match);
+
+static const struct i2c_device_id bma220_i2c_id[] = {
+	{ "bma220" },
+	{ }
+};
+MODULE_DEVICE_TABLE(i2c, bma220_i2c_id);
+
+static struct i2c_driver bma220_i2c_driver = {
+	.driver = {
+		.name = "bma220_i2c",
+		.pm = pm_sleep_ptr(&bma220_pm_ops),
+		.of_match_table = bma220_i2c_match,
+	},
+	.probe = bma220_i2c_probe,
+	.id_table = bma220_i2c_id,
+};
+module_i2c_driver(bma220_i2c_driver);
+
+MODULE_AUTHOR("Petre Rodan <petre.rodan@subdimension.ro>");
+MODULE_DESCRIPTION("Bosch triaxial acceleration sensor i2c driver");
+MODULE_LICENSE("GPL");
+MODULE_IMPORT_NS("IIO_BOSCH_BMA220");

-- 
2.49.1

Re: [PATCH v4 14/19] iio: accel: bma220: add i2c module

[Jonathan Cameron]

On Sun, 05 Oct 2025 16:12:23 +0300
Petre Rodan <petre.rodan@subdimension.ro> wrote:

> Add the bma220_i2c module.
> 
> Note that this kernel module transparently shifts all register addresses
> 1 bit to the left, so all functions will operate based on the SPI memory
> map.
> 
> Signed-off-by: Petre Rodan <petre.rodan@subdimension.ro>
Applied. Note that it was only when I reached here I realized I failed
to add the bma220.h when hand applying things earlier.  Anyhow I went
back and fixed that up, but there a few little differences in ordering.
I took the view it was close enough that I didn't go back and do it a 3rd time.
Nothing affects eventual state, just position of the temporary struct spi_device;
forwards declaration I think.

Anyhow, after that this applied cleanly so all good

Thanks,

Jonathan

[PATCH v4 15/19] iio: accel: bma220: add i2c watchdog feature

[Petre Rodan]

Sometimes the sensor gets stuck and enters a condition in which it pulls
SDA low, thus making the entire i2c bus unusable.
This problem is mitigated by activating a 1ms watchdog implemented in
the sensor.

Signed-off-by: Petre Rodan <petre.rodan@subdimension.ro>
---
v1->v2
- hardcode 1ms timer watchdog to any i2c-based sensor instead of
  configuring a dt-based property
- rename bma220_wdt() to bma220_set_wdt()
v2->v4 no change
---
 drivers/iio/accel/bma220_core.c | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/drivers/iio/accel/bma220_core.c b/drivers/iio/accel/bma220_core.c
index a3faf1f5ec6d79f2c6105697b404d6eb1f4501db..a957751be40c63c25963283be813db97f73bf004 100644
--- a/drivers/iio/accel/bma220_core.c
+++ b/drivers/iio/accel/bma220_core.c
@@ -10,6 +10,7 @@
 #include <linux/bitfield.h>
 #include <linux/cleanup.h>
 #include <linux/device.h>
+#include <linux/i2c.h>
 #include <linux/mod_devicetable.h>
 #include <linux/module.h>
 #include <linux/mutex.h>
@@ -355,6 +356,12 @@ static int bma220_power(struct bma220_data *data, bool up)
 	return -EBUSY;
 }
 
+static int bma220_set_wdt(struct bma220_data *data, const u8 val)
+{
+	return regmap_update_bits(data->regmap, BMA220_REG_WDT, BMA220_WDT_MASK,
+				  FIELD_PREP(BMA220_WDT_MASK, val));
+}
+
 static int bma220_init(struct device *dev, struct bma220_data *data)
 {
 	int ret;
@@ -383,6 +390,13 @@ static int bma220_init(struct device *dev, struct bma220_data *data)
 	if (ret)
 		return dev_err_probe(dev, ret, "Failed to soft reset chip\n");
 
+	if (i2c_verify_client(dev)) {
+		ret = bma220_set_wdt(data, BMA220_WDT_1MS);
+		if (ret)
+			return dev_err_probe(dev, ret,
+					     "Failed to set i2c watchdog\n");
+	}
+
 	return 0;
 }
 

-- 
2.49.1

Re: [PATCH v4 15/19] iio: accel: bma220: add i2c watchdog feature

[Jonathan Cameron]

On Sun, 05 Oct 2025 16:12:24 +0300
Petre Rodan <petre.rodan@subdimension.ro> wrote:

> Sometimes the sensor gets stuck and enters a condition in which it pulls
> SDA low, thus making the entire i2c bus unusable.
> This problem is mitigated by activating a 1ms watchdog implemented in
> the sensor.
> 
> Signed-off-by: Petre Rodan <petre.rodan@subdimension.ro>
Applied.

Thanks.

J

[PATCH v4 16/19] iio: accel: bma220: add interrupt trigger

[Petre Rodan]

Add interrupt trigger.

Signed-off-by: Petre Rodan <petre.rodan@subdimension.ro>
---
v1->v2 no change, just patch split
v2->v3 replace regmap_bulk_read with regmap_read (Jonathan)
 (I just realized BMA220_REG_IF0 is never used, even by future
 event patches)
v4 fix compilation err
---
 drivers/iio/accel/bma220_core.c | 58 +++++++++++++++++++++++++++++++++++++++++
 1 file changed, 58 insertions(+)

diff --git a/drivers/iio/accel/bma220_core.c b/drivers/iio/accel/bma220_core.c
index a957751be40c63c25963283be813db97f73bf004..8f0cbd0aacb92a21afc57aaa350547d0c767d4b6 100644
--- a/drivers/iio/accel/bma220_core.c
+++ b/drivers/iio/accel/bma220_core.c
@@ -22,6 +22,7 @@
 #include <linux/iio/buffer.h>
 #include <linux/iio/iio.h>
 #include <linux/iio/sysfs.h>
+#include <linux/iio/trigger.h>
 #include <linux/iio/trigger_consumer.h>
 #include <linux/iio/triggered_buffer.h>
 
@@ -123,6 +124,7 @@ struct bma220_data {
 	struct regmap *regmap;
 	struct mutex lock;
 	u8 range_idx;
+	struct iio_trigger *trig;
 	struct {
 		s8 chans[3];
 		/* Ensure timestamp is naturally aligned. */
@@ -191,6 +193,22 @@ const struct regmap_config bma220_i2c_regmap_config = {
 };
 EXPORT_SYMBOL_NS_GPL(bma220_i2c_regmap_config, "IIO_BOSCH_BMA220");
 
+static int bma220_data_rdy_trigger_set_state(struct iio_trigger *trig,
+					     bool state)
+{
+	struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig);
+	struct bma220_data *data = iio_priv(indio_dev);
+
+	return regmap_update_bits(data->regmap, BMA220_REG_IE0,
+				  BMA220_INT_EN_DRDY_MSK,
+				  FIELD_PREP(BMA220_INT_EN_DRDY_MSK, state));
+}
+
+static const struct iio_trigger_ops bma220_trigger_ops = {
+	.set_trigger_state = &bma220_data_rdy_trigger_set_state,
+	.validate_device = &iio_trigger_validate_own_device,
+};
+
 static irqreturn_t bma220_trigger_handler(int irq, void *p)
 {
 	int ret;
@@ -413,6 +431,23 @@ static void bma220_deinit(void *data_ptr)
 			 ERR_PTR(ret));
 }
 
+static irqreturn_t bma220_irq_handler(int irq, void *private)
+{
+	struct iio_dev *indio_dev = private;
+	struct bma220_data *data = iio_priv(indio_dev);
+	int ret;
+	unsigned int bma220_reg_if1;
+
+	ret = regmap_read(data->regmap, BMA220_REG_IF1, &bma220_reg_if1);
+	if (ret)
+		return IRQ_NONE;
+
+	if (FIELD_GET(BMA220_IF_DRDY, bma220_reg_if1))
+		iio_trigger_poll_nested(data->trig);
+
+	return IRQ_HANDLED;
+}
+
 int bma220_common_probe(struct device *dev, struct regmap *regmap, int irq)
 {
 	int ret;
@@ -441,6 +476,29 @@ int bma220_common_probe(struct device *dev, struct regmap *regmap, int irq)
 	indio_dev->num_channels = ARRAY_SIZE(bma220_channels);
 	indio_dev->available_scan_masks = bma220_accel_scan_masks;
 
+	if (irq > 0) {
+		data->trig = devm_iio_trigger_alloc(dev, "%s-dev%d",
+						    indio_dev->name,
+						    iio_device_id(indio_dev));
+		if (!data->trig)
+			return -ENOMEM;
+
+		data->trig->ops = &bma220_trigger_ops;
+		iio_trigger_set_drvdata(data->trig, indio_dev);
+
+		ret = devm_iio_trigger_register(dev, data->trig);
+		if (ret)
+			return dev_err_probe(dev, ret,
+					     "iio trigger register fail\n");
+		indio_dev->trig = iio_trigger_get(data->trig);
+		ret = devm_request_threaded_irq(dev, irq, NULL,
+						&bma220_irq_handler, IRQF_ONESHOT,
+						indio_dev->name, indio_dev);
+		if (ret)
+			return dev_err_probe(dev, ret,
+					     "request irq %d failed\n", irq);
+	}
+
 	ret = devm_add_action_or_reset(dev, bma220_deinit, data);
 	if (ret)
 		return ret;

-- 
2.49.1

Re: [PATCH v4 16/19] iio: accel: bma220: add interrupt trigger

[Jonathan Cameron]

On Sun, 05 Oct 2025 16:12:25 +0300
Petre Rodan <petre.rodan@subdimension.ro> wrote:

> Add interrupt trigger.
> 
> Signed-off-by: Petre Rodan <petre.rodan@subdimension.ro>
Applied.

Thanks,

Jonathan

[PATCH v4 17/19] iio: accel: bma220: add LPF cut-off frequency mapping

[Petre Rodan]

Add mapping for the low pass filter cut-off frequency.
Make valid values visible for both the cut-off frequency and the scale.

Signed-off-by: Petre Rodan <petre.rodan@subdimension.ro>
---
v1->v2 rename variables to include unit capitalization (dB, Hz)
v2->v3 make comment one-liner (Jonathan)
v4 no change
---
 drivers/iio/accel/bma220_core.c | 59 ++++++++++++++++++++++++++++++++++++++++-
 1 file changed, 58 insertions(+), 1 deletion(-)

diff --git a/drivers/iio/accel/bma220_core.c b/drivers/iio/accel/bma220_core.c
index 8f0cbd0aacb92a21afc57aaa350547d0c767d4b6..7109759e28397d2660f17707124a8803a254cb14 100644
--- a/drivers/iio/accel/bma220_core.c
+++ b/drivers/iio/accel/bma220_core.c
@@ -93,13 +93,23 @@
 
 #define BMA220_DEVICE_NAME			"bma220"
 
+#define BMA220_COF_1000Hz			0x0
+#define BMA220_COF_500Hz			0x1
+#define BMA220_COF_250Hz			0x2
+#define BMA220_COF_125Hz			0x3
+#define BMA220_COF_64Hz				0x4
+#define BMA220_COF_32Hz				0x5
+
 #define BMA220_ACCEL_CHANNEL(index, reg, axis) {			\
 	.type = IIO_ACCEL,						\
 	.address = reg,							\
 	.modified = 1,							\
 	.channel2 = IIO_MOD_##axis,					\
 	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),			\
-	.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),		\
+	.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) |		\
+	    BIT(IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY),		\
+	.info_mask_shared_by_type_available = BIT(IIO_CHAN_INFO_SCALE) |\
+	    BIT(IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY),		\
 	.scan_index = index,						\
 	.scan_type = {							\
 		.sign = 's',						\
@@ -123,6 +133,7 @@ static const int bma220_scale_table[][2] = {
 struct bma220_data {
 	struct regmap *regmap;
 	struct mutex lock;
+	u8 lpf_3dB_freq_idx;
 	u8 range_idx;
 	struct iio_trigger *trig;
 	struct {
@@ -139,6 +150,16 @@ static const struct iio_chan_spec bma220_channels[] = {
 	IIO_CHAN_SOFT_TIMESTAMP(3),
 };
 
+/* Available cut-off frequencies of the low pass filter in Hz. */
+static const int bma220_lpf_3dB_freq_Hz_table[] = {
+	[BMA220_COF_1000Hz] = 1000,
+	[BMA220_COF_500Hz] = 500,
+	[BMA220_COF_250Hz] = 250,
+	[BMA220_COF_125Hz] = 125,
+	[BMA220_COF_64Hz] = 64,
+	[BMA220_COF_32Hz] = 32,
+};
+
 static const unsigned long bma220_accel_scan_masks[] = {
 	BIT(AXIS_X) | BIT(AXIS_Y) | BIT(AXIS_Z),
 	0
@@ -253,6 +274,10 @@ static int bma220_read_raw(struct iio_dev *indio_dev,
 		*val = bma220_scale_table[index][0];
 		*val2 = bma220_scale_table[index][1];
 		return IIO_VAL_INT_PLUS_MICRO;
+	case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY:
+		index = data->lpf_3dB_freq_idx;
+		*val = bma220_lpf_3dB_freq_Hz_table[index];
+		return IIO_VAL_INT;
 	}
 
 	return -EINVAL;
@@ -271,6 +296,18 @@ static int bma220_find_match_2dt(const int (*tbl)[2], const int n,
 	return -EINVAL;
 }
 
+static int bma220_find_match(const int *arr, const int n, const int val)
+{
+	int i;
+
+	for (i = 0; i < n; i++) {
+		if (arr[i] == val)
+			return i;
+	}
+
+	return -EINVAL;
+}
+
 static int bma220_write_raw(struct iio_dev *indio_dev,
 			    struct iio_chan_spec const *chan,
 			    int val, int val2, long mask)
@@ -296,6 +333,21 @@ static int bma220_write_raw(struct iio_dev *indio_dev,
 			return ret;
 		data->range_idx = index;
 
+		return 0;
+	case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY:
+		index = bma220_find_match(bma220_lpf_3dB_freq_Hz_table,
+					  ARRAY_SIZE(bma220_lpf_3dB_freq_Hz_table),
+					  val);
+		if (index < 0)
+			return -EINVAL;
+
+		ret = regmap_update_bits(data->regmap, BMA220_REG_FILTER,
+					 BMA220_FILTER_MASK,
+					 FIELD_PREP(BMA220_FILTER_MASK, index));
+		if (ret < 0)
+			return ret;
+		data->lpf_3dB_freq_idx = index;
+
 		return 0;
 	}
 
@@ -313,6 +365,11 @@ static int bma220_read_avail(struct iio_dev *indio_dev,
 		*type = IIO_VAL_INT_PLUS_MICRO;
 		*length = ARRAY_SIZE(bma220_scale_table) * 2;
 		return IIO_AVAIL_LIST;
+	case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY:
+		*vals = (const int *)bma220_lpf_3dB_freq_Hz_table;
+		*type = IIO_VAL_INT;
+		*length = ARRAY_SIZE(bma220_lpf_3dB_freq_Hz_table);
+		return IIO_AVAIL_LIST;
 	default:
 		return -EINVAL;
 	}

-- 
2.49.1

Re: [PATCH v4 17/19] iio: accel: bma220: add LPF cut-off frequency mapping

[Jonathan Cameron]

On Sun, 05 Oct 2025 16:12:26 +0300
Petre Rodan <petre.rodan@subdimension.ro> wrote:

> Add mapping for the low pass filter cut-off frequency.
> Make valid values visible for both the cut-off frequency and the scale.
> 
> Signed-off-by: Petre Rodan <petre.rodan@subdimension.ro>
Applied.

[PATCH v4 18/19] iio: accel: bma220: add debugfs reg access

[Petre Rodan]

Allow read/write access to sensor registers for use in unit-tests.

Signed-off-by: Petre Rodan <petre.rodan@subdimension.ro>
---
v1->v4 no change
---
 drivers/iio/accel/bma220_core.c | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/drivers/iio/accel/bma220_core.c b/drivers/iio/accel/bma220_core.c
index 7109759e28397d2660f17707124a8803a254cb14..0d6c301b1c47a04cfca5bae157f8ce6144f0b854 100644
--- a/drivers/iio/accel/bma220_core.c
+++ b/drivers/iio/accel/bma220_core.c
@@ -375,10 +375,21 @@ static int bma220_read_avail(struct iio_dev *indio_dev,
 	}
 }
 
+static int bma220_reg_access(struct iio_dev *indio_dev, unsigned int reg,
+			     unsigned int writeval, unsigned int *readval)
+{
+	struct bma220_data *data = iio_priv(indio_dev);
+
+	if (readval)
+		return regmap_read(data->regmap, reg, readval);
+	return regmap_write(data->regmap, reg, writeval);
+}
+
 static const struct iio_info bma220_info = {
 	.read_raw		= bma220_read_raw,
 	.write_raw		= bma220_write_raw,
 	.read_avail		= bma220_read_avail,
+	.debugfs_reg_access	= &bma220_reg_access,
 };
 
 static int bma220_reset(struct bma220_data *data, bool up)

-- 
2.49.1

Re: [PATCH v4 18/19] iio: accel: bma220: add debugfs reg access

[Jonathan Cameron]

On Sun, 05 Oct 2025 16:12:27 +0300
Petre Rodan <petre.rodan@subdimension.ro> wrote:

> Allow read/write access to sensor registers for use in unit-tests.
> 
> Signed-off-by: Petre Rodan <petre.rodan@subdimension.ro>
Applied.

[PATCH v4 19/19] iio: accel: bma220: add maintainer

[Petre Rodan]

Add maintainer for this driver.

Signed-off-by: Petre Rodan <petre.rodan@subdimension.ro>
---
v1->v4 no change
---
 MAINTAINERS | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/MAINTAINERS b/MAINTAINERS
index f090c2f6e63a0d255a025885cc4573f5802ef159..aaeb4ae6fd2282264da7e61b6fc32c00fc90a5ae 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -4402,6 +4402,13 @@ F:	include/net/bond*
 F:	include/uapi/linux/if_bonding.h
 F:	tools/testing/selftests/drivers/net/bonding/
 
+BOSCH SENSORTEC BMA220 ACCELEROMETER IIO DRIVER
+M:	Petre Rodan <petre.rodan@subdimension.ro>
+L:	linux-iio@vger.kernel.org
+S:	Maintained
+F:	Documentation/devicetree/bindings/iio/accel/bosch,bma220.yaml
+F:	drivers/iio/accel/bma220*
+
 BOSCH SENSORTEC BMA400 ACCELEROMETER IIO DRIVER
 M:	Dan Robertson <dan@dlrobertson.com>
 L:	linux-iio@vger.kernel.org

-- 
2.49.1

Re: [PATCH v4 19/19] iio: accel: bma220: add maintainer

[Jonathan Cameron]

On Sun, 05 Oct 2025 16:12:28 +0300
Petre Rodan <petre.rodan@subdimension.ro> wrote:

> Add maintainer for this driver.
> 
> Signed-off-by: Petre Rodan <petre.rodan@subdimension.ro>
Applied. Thanks for stepping up to maintain this going forwards

Jonathan

> ---
> v1->v4 no change
> ---
>  MAINTAINERS | 7 +++++++
>  1 file changed, 7 insertions(+)
> 
> diff --git a/MAINTAINERS b/MAINTAINERS
> index f090c2f6e63a0d255a025885cc4573f5802ef159..aaeb4ae6fd2282264da7e61b6fc32c00fc90a5ae 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -4402,6 +4402,13 @@ F:	include/net/bond*
>  F:	include/uapi/linux/if_bonding.h
>  F:	tools/testing/selftests/drivers/net/bonding/
>  
> +BOSCH SENSORTEC BMA220 ACCELEROMETER IIO DRIVER
> +M:	Petre Rodan <petre.rodan@subdimension.ro>
> +L:	linux-iio@vger.kernel.org
> +S:	Maintained
> +F:	Documentation/devicetree/bindings/iio/accel/bosch,bma220.yaml
> +F:	drivers/iio/accel/bma220*
> +
>  BOSCH SENSORTEC BMA400 ACCELEROMETER IIO DRIVER
>  M:	Dan Robertson <dan@dlrobertson.com>
>  L:	linux-iio@vger.kernel.org
>