[PATCH v4 0/3] Support all AKM compass in a single driver

[PATCH v4 0/3] Support all AKM compass in a single driver

[Gwendal Grignou]

Currently, 2 drivers are used for supporting AKM compasses:
- ak8975 and ak8963 in ak875.c: these compasses support DRDY line and interrupt.
- ak09911 in ak0911.c: this compass has a new register map and does not support DRDY line.

A newer compass, ak09912 has the same register map as ak09911 but the same functionality as
ak8975. By adding support to ak09912 into ak8975, we can remove the driver specific to ak09911.


Gwendal Grignou (3):
  iio: ak8975: minor fixes
  iio: ak8975: add definition structure per compass type
  iio: ak8975: add ak09911 and ak09912 support

 drivers/iio/magnetometer/Kconfig   |  15 +-
 drivers/iio/magnetometer/Makefile  |   1 -
 drivers/iio/magnetometer/ak09911.c | 326 ------------------------
 drivers/iio/magnetometer/ak8975.c  | 501 +++++++++++++++++++++++++++----------
 4 files changed, 378 insertions(+), 465 deletions(-)
 delete mode 100644 drivers/iio/magnetometer/ak09911.c

Reviewed-by: Hartmut Knaack <knaack.h@gmx.de>
Tested-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
-- 
2.1.0.rc2.206.gedb03e5

[PATCH v4 1/3] iio: ak8975: minor fixes

[Gwendal Grignou]

Fixes code duplication, return of function.
Check client->irq properly when setting up optional irq handler.

Signed-off-by: Gwendal Grignou <gwendal@chromium.org>
Reviewed-by: Hartmut Knaack <knaack.h@gmx.de>
---
 drivers/iio/magnetometer/ak8975.c | 35 ++++++++++++++---------------------
 1 file changed, 14 insertions(+), 21 deletions(-)

diff --git a/drivers/iio/magnetometer/ak8975.c b/drivers/iio/magnetometer/ak8975.c
index bf5ef07..4e69480 100644
--- a/drivers/iio/magnetometer/ak8975.c
+++ b/drivers/iio/magnetometer/ak8975.c
@@ -64,10 +64,10 @@
 #define AK8975_REG_CNTL			0x0A
 #define AK8975_REG_CNTL_MODE_SHIFT	0
 #define AK8975_REG_CNTL_MODE_MASK	(0xF << AK8975_REG_CNTL_MODE_SHIFT)
-#define AK8975_REG_CNTL_MODE_POWER_DOWN	0
-#define AK8975_REG_CNTL_MODE_ONCE	1
-#define AK8975_REG_CNTL_MODE_SELF_TEST	8
-#define AK8975_REG_CNTL_MODE_FUSE_ROM	0xF
+#define AK8975_REG_CNTL_MODE_POWER_DOWN	0x00
+#define AK8975_REG_CNTL_MODE_ONCE	0x01
+#define AK8975_REG_CNTL_MODE_SELF_TEST	0x08
+#define AK8975_REG_CNTL_MODE_FUSE_ROM	0x0F
 
 #define AK8975_REG_RSVC			0x0B
 #define AK8975_REG_ASTC			0x0C
@@ -166,8 +166,8 @@ static int ak8975_setup_irq(struct ak8975_data *data)
 		irq = gpio_to_irq(data->eoc_gpio);
 
 	rc = devm_request_irq(&client->dev, irq, ak8975_irq_handler,
-			 IRQF_TRIGGER_RISING | IRQF_ONESHOT,
-			 dev_name(&client->dev), data);
+			      IRQF_TRIGGER_RISING | IRQF_ONESHOT,
+			      dev_name(&client->dev), data);
 	if (rc < 0) {
 		dev_err(&client->dev,
 			"irq %d request failed, (gpio %d): %d\n",
@@ -231,8 +231,12 @@ static int ak8975_setup(struct i2c_client *client)
 				AK8975_REG_CNTL_MODE_POWER_DOWN,
 				AK8975_REG_CNTL_MODE_MASK,
 				AK8975_REG_CNTL_MODE_SHIFT);
+	if (ret < 0) {
+		dev_err(&client->dev, "Error in setting power-down mode\n");
+		return ret;
+	}
 
-	if (data->eoc_gpio > 0 || client->irq) {
+	if (data->eoc_gpio > 0 || client->irq > 0) {
 		ret = ak8975_setup_irq(data);
 		if (ret < 0) {
 			dev_err(&client->dev,
@@ -241,11 +245,6 @@ static int ak8975_setup(struct i2c_client *client)
 		}
 	}
 
-	if (ret < 0) {
-		dev_err(&client->dev, "Error in setting power-down mode\n");
-		return ret;
-	}
-
 /*
  * Precalculate scale factor (in Gauss units) for each axis and
  * store in the device data.
@@ -550,24 +549,18 @@ static int ak8975_probe(struct i2c_client *client,
 	/* Perform some basic start-of-day setup of the device. */
 	err = ak8975_setup(client);
 	if (err < 0) {
-		dev_err(&client->dev, "AK8975 initialization fails\n");
+		dev_err(&client->dev, "%s initialization fails\n", name);
 		return err;
 	}
 
-	data->client = client;
 	mutex_init(&data->lock);
-	data->eoc_gpio = eoc_gpio;
 	indio_dev->dev.parent = &client->dev;
 	indio_dev->channels = ak8975_channels;
 	indio_dev->num_channels = ARRAY_SIZE(ak8975_channels);
 	indio_dev->info = &ak8975_info;
 	indio_dev->modes = INDIO_DIRECT_MODE;
 	indio_dev->name = name;
-	err = devm_iio_device_register(&client->dev, indio_dev);
-	if (err < 0)
-		return err;
-
-	return 0;
+	return devm_iio_device_register(&client->dev, indio_dev);
 }
 
 static const struct i2c_device_id ak8975_id[] = {
@@ -588,7 +581,7 @@ MODULE_DEVICE_TABLE(of, ak8975_of_match);
 static struct i2c_driver ak8975_driver = {
 	.driver = {
 		.name	= "ak8975",
-		.of_match_table = ak8975_of_match,
+		.of_match_table = of_match_ptr(ak8975_of_match),
 		.acpi_match_table = ACPI_PTR(ak_acpi_match),
 	},
 	.probe		= ak8975_probe,
-- 
2.1.0.rc2.206.gedb03e5

Re: [PATCH v4 1/3] iio: ak8975: minor fixes

[Jonathan Cameron]

On 21/11/14 18:45, Gwendal Grignou wrote:
> Fixes code duplication, return of function.
> Check client->irq properly when setting up optional irq handler.
> 
> Signed-off-by: Gwendal Grignou <gwendal@chromium.org>
> Reviewed-by: Hartmut Knaack <knaack.h@gmx.de>
Applied to the togreg branch of iio.git - pushed out as testing for the
autobuilder to play with it.

Thanks,

Jonathan
> ---
>  drivers/iio/magnetometer/ak8975.c | 35 ++++++++++++++---------------------
>  1 file changed, 14 insertions(+), 21 deletions(-)
> 
> diff --git a/drivers/iio/magnetometer/ak8975.c b/drivers/iio/magnetometer/ak8975.c
> index bf5ef07..4e69480 100644
> --- a/drivers/iio/magnetometer/ak8975.c
> +++ b/drivers/iio/magnetometer/ak8975.c
> @@ -64,10 +64,10 @@
>  #define AK8975_REG_CNTL			0x0A
>  #define AK8975_REG_CNTL_MODE_SHIFT	0
>  #define AK8975_REG_CNTL_MODE_MASK	(0xF << AK8975_REG_CNTL_MODE_SHIFT)
> -#define AK8975_REG_CNTL_MODE_POWER_DOWN	0
> -#define AK8975_REG_CNTL_MODE_ONCE	1
> -#define AK8975_REG_CNTL_MODE_SELF_TEST	8
> -#define AK8975_REG_CNTL_MODE_FUSE_ROM	0xF
> +#define AK8975_REG_CNTL_MODE_POWER_DOWN	0x00
> +#define AK8975_REG_CNTL_MODE_ONCE	0x01
> +#define AK8975_REG_CNTL_MODE_SELF_TEST	0x08
> +#define AK8975_REG_CNTL_MODE_FUSE_ROM	0x0F
>  
>  #define AK8975_REG_RSVC			0x0B
>  #define AK8975_REG_ASTC			0x0C
> @@ -166,8 +166,8 @@ static int ak8975_setup_irq(struct ak8975_data *data)
>  		irq = gpio_to_irq(data->eoc_gpio);
>  
>  	rc = devm_request_irq(&client->dev, irq, ak8975_irq_handler,
> -			 IRQF_TRIGGER_RISING | IRQF_ONESHOT,
> -			 dev_name(&client->dev), data);
> +			      IRQF_TRIGGER_RISING | IRQF_ONESHOT,
> +			      dev_name(&client->dev), data);
>  	if (rc < 0) {
>  		dev_err(&client->dev,
>  			"irq %d request failed, (gpio %d): %d\n",
> @@ -231,8 +231,12 @@ static int ak8975_setup(struct i2c_client *client)
>  				AK8975_REG_CNTL_MODE_POWER_DOWN,
>  				AK8975_REG_CNTL_MODE_MASK,
>  				AK8975_REG_CNTL_MODE_SHIFT);
> +	if (ret < 0) {
> +		dev_err(&client->dev, "Error in setting power-down mode\n");
> +		return ret;
> +	}
>  
> -	if (data->eoc_gpio > 0 || client->irq) {
> +	if (data->eoc_gpio > 0 || client->irq > 0) {
>  		ret = ak8975_setup_irq(data);
>  		if (ret < 0) {
>  			dev_err(&client->dev,
> @@ -241,11 +245,6 @@ static int ak8975_setup(struct i2c_client *client)
>  		}
>  	}
>  
> -	if (ret < 0) {
> -		dev_err(&client->dev, "Error in setting power-down mode\n");
> -		return ret;
> -	}
> -
>  /*
>   * Precalculate scale factor (in Gauss units) for each axis and
>   * store in the device data.
> @@ -550,24 +549,18 @@ static int ak8975_probe(struct i2c_client *client,
>  	/* Perform some basic start-of-day setup of the device. */
>  	err = ak8975_setup(client);
>  	if (err < 0) {
> -		dev_err(&client->dev, "AK8975 initialization fails\n");
> +		dev_err(&client->dev, "%s initialization fails\n", name);
>  		return err;
>  	}
>  
> -	data->client = client;
>  	mutex_init(&data->lock);
> -	data->eoc_gpio = eoc_gpio;
>  	indio_dev->dev.parent = &client->dev;
>  	indio_dev->channels = ak8975_channels;
>  	indio_dev->num_channels = ARRAY_SIZE(ak8975_channels);
>  	indio_dev->info = &ak8975_info;
>  	indio_dev->modes = INDIO_DIRECT_MODE;
>  	indio_dev->name = name;
> -	err = devm_iio_device_register(&client->dev, indio_dev);
> -	if (err < 0)
> -		return err;
> -
> -	return 0;
> +	return devm_iio_device_register(&client->dev, indio_dev);
>  }
>  
>  static const struct i2c_device_id ak8975_id[] = {
> @@ -588,7 +581,7 @@ MODULE_DEVICE_TABLE(of, ak8975_of_match);
>  static struct i2c_driver ak8975_driver = {
>  	.driver = {
>  		.name	= "ak8975",
> -		.of_match_table = ak8975_of_match,
> +		.of_match_table = of_match_ptr(ak8975_of_match),
>  		.acpi_match_table = ACPI_PTR(ak_acpi_match),
>  	},
>  	.probe		= ak8975_probe,
> 

[PATCH v4 2/3] iio: ak8975: add definition structure per compass type

[Gwendal Grignou]

For each type of compass supported (AK8975 and AK8963),
add a definition structure for register masks, important registers,
raw data interpretation.
This change will make integrating new type of devices easier.

Remove i2c register cache. It is only used for one single register.

Signed-off-by: Gwendal Grignou <gwendal@chromium.org>
---
 drivers/iio/magnetometer/ak8975.c | 279 +++++++++++++++++++++++++-------------
 1 file changed, 184 insertions(+), 95 deletions(-)

diff --git a/drivers/iio/magnetometer/ak8975.c b/drivers/iio/magnetometer/ak8975.c
index 4e69480..58c9a78 100644
--- a/drivers/iio/magnetometer/ak8975.c
+++ b/drivers/iio/magnetometer/ak8975.c
@@ -86,13 +86,153 @@
 #define AK8975_MAX_CONVERSION_TIMEOUT	500
 #define AK8975_CONVERSION_DONE_POLL_TIME 10
 #define AK8975_DATA_READY_TIMEOUT	((100*HZ)/1000)
-#define RAW_TO_GAUSS_8975(asa) ((((asa) + 128) * 3000) / 256)
-#define RAW_TO_GAUSS_8963(asa) ((((asa) + 128) * 6000) / 256)
+
+/*
+ * Precalculate scale factor (in Gauss units) for each axis and
+ * store in the device data.
+ *
+ * This scale factor is axis-dependent, and is derived from 3 calibration
+ * factors ASA(x), ASA(y), and ASA(z).
+ *
+ * These ASA values are read from the sensor device at start of day, and
+ * cached in the device context struct.
+ *
+ * Adjusting the flux value with the sensitivity adjustment value should be
+ * done via the following formula:
+ *
+ * Hadj = H * ( ( ( (ASA-128)*0.5 ) / 128 ) + 1 )
+ * where H is the raw value, ASA is the sensitivity adjustment, and Hadj
+ * is the resultant adjusted value.
+ *
+ * We reduce the formula to:
+ *
+ * Hadj = H * (ASA + 128) / 256
+ *
+ * H is in the range of -4096 to 4095.  The magnetometer has a range of
+ * +-1229uT.  To go from the raw value to uT is:
+ *
+ * HuT = H * 1229/4096, or roughly, 3/10.
+ *
+ * Since 1uT = 0.01 gauss, our final scale factor becomes:
+ *
+ * Hadj = H * ((ASA + 128) / 256) * 3/10 * 1/100
+ * Hadj = H * ((ASA + 128) * 0.003) / 256
+ *
+ * Since ASA doesn't change, we cache the resultant scale factor into the
+ * device context in ak8975_setup().
+ *
+ * Given we use IIO_VAL_INT_PLUS_MICRO bit when displaying the scale, we
+ * multiply the stored scale value by 1e6.
+ */
+long ak8975_raw_to_gauss(u16 data)
+{
+	return (((long)data + 128) * 3000) / 256;
+}
+
+/*
+ * For AK8963, same calculation, but the device is less sensitive:
+ *
+ * H is in the range of +-8190.  The magnetometer has a range of
+ * +-4912uT.  To go from the raw value to uT is:
+ *
+ * HuT = H * 4912/8190, or roughly, 6/10, instead of 3/10.
+ */
+long ak8963_raw_to_gauss(u16 data)
+{
+	return (((long)data + 128) * 6000) / 256;
+}
 
 /* Compatible Asahi Kasei Compass parts */
 enum asahi_compass_chipset {
 	AK8975,
 	AK8963,
+	AK_MAX_TYPE
+};
+
+enum ak_ctrl_reg_addr {
+	ST1,
+	ST2,
+	CNTL,
+	ASA_BASE,
+	MAX_REGS,
+	REGS_END,
+};
+
+enum ak_ctrl_reg_mask {
+	ST1_DRDY,
+	ST2_HOFL,
+	ST2_DERR,
+	CNTL_MODE,
+	MASK_END,
+};
+
+enum ak_ctrl_mode {
+	POWER_DOWN,
+	MODE_ONCE,
+	SELF_TEST,
+	FUSE_ROM,
+	MODE_END,
+};
+
+struct ak_def {
+	enum asahi_compass_chipset type;
+	long (*raw_to_gauss)(u16 data);
+	u16 range;
+	u8 ctrl_regs[REGS_END];
+	u8 ctrl_masks[MASK_END];
+	u8 ctrl_modes[MODE_END];
+	u8 data_regs[3];
+} ak_def_array[AK_MAX_TYPE] = {
+	{
+		.type = AK8975,
+		.raw_to_gauss = ak8975_raw_to_gauss,
+		.range = 4096,
+		.ctrl_regs = {
+			AK8975_REG_ST1,
+			AK8975_REG_ST2,
+			AK8975_REG_CNTL,
+			AK8975_REG_ASAX,
+			AK8975_MAX_REGS},
+		.ctrl_masks = {
+			AK8975_REG_ST1_DRDY_MASK,
+			AK8975_REG_ST2_HOFL_MASK,
+			AK8975_REG_ST2_DERR_MASK,
+			AK8975_REG_CNTL_MODE_MASK},
+		.ctrl_modes = {
+			AK8975_REG_CNTL_MODE_POWER_DOWN,
+			AK8975_REG_CNTL_MODE_ONCE,
+			AK8975_REG_CNTL_MODE_SELF_TEST,
+			AK8975_REG_CNTL_MODE_FUSE_ROM},
+		.data_regs = {
+			AK8975_REG_HXL,
+			AK8975_REG_HYL,
+			AK8975_REG_HZL},
+	},
+	{
+		.type = AK8963,
+		.raw_to_gauss = ak8963_raw_to_gauss,
+		.range = 8190,
+		.ctrl_regs = {
+			AK8975_REG_ST1,
+			AK8975_REG_ST2,
+			AK8975_REG_CNTL,
+			AK8975_REG_ASAX,
+			AK8975_MAX_REGS},
+		.ctrl_masks = {
+			AK8975_REG_ST1_DRDY_MASK,
+			AK8975_REG_ST2_HOFL_MASK,
+			0,
+			AK8975_REG_CNTL_MODE_MASK},
+		.ctrl_modes = {
+			AK8975_REG_CNTL_MODE_POWER_DOWN,
+			AK8975_REG_CNTL_MODE_ONCE,
+			AK8975_REG_CNTL_MODE_SELF_TEST,
+			AK8975_REG_CNTL_MODE_FUSE_ROM},
+		.data_regs = {
+			AK8975_REG_HXL,
+			AK8975_REG_HYL,
+			AK8975_REG_HZL},
+	},
 };
 
 /*
@@ -100,40 +240,36 @@ enum asahi_compass_chipset {
  */
 struct ak8975_data {
 	struct i2c_client	*client;
+	struct ak_def		*def;
 	struct attribute_group	attrs;
 	struct mutex		lock;
 	u8			asa[3];
 	long			raw_to_gauss[3];
-	u8			reg_cache[AK8975_MAX_REGS];
 	int			eoc_gpio;
 	int			eoc_irq;
 	wait_queue_head_t	data_ready_queue;
 	unsigned long		flags;
-	enum asahi_compass_chipset chipset;
-};
-
-static const int ak8975_index_to_reg[] = {
-	AK8975_REG_HXL, AK8975_REG_HYL, AK8975_REG_HZL,
+	u8			cntl_cache;
 };
 
 /*
- * Helper function to write to the I2C device's registers.
+ * Helper function to write to CNTL register.
  */
-static int ak8975_write_data(struct i2c_client *client,
-			     u8 reg, u8 val, u8 mask, u8 shift)
+static int ak8975_set_mode(struct ak8975_data *data, enum ak_ctrl_mode mode)
 {
-	struct iio_dev *indio_dev = i2c_get_clientdata(client);
-	struct ak8975_data *data = iio_priv(indio_dev);
 	u8 regval;
 	int ret;
 
-	regval = (data->reg_cache[reg] & ~mask) | (val << shift);
-	ret = i2c_smbus_write_byte_data(client, reg, regval);
+	regval = (data->cntl_cache & ~data->def->ctrl_masks[CNTL_MODE]) |
+		 data->def->ctrl_modes[mode];
+	ret = i2c_smbus_write_byte_data(data->client,
+			data->def->ctrl_regs[CNTL], regval);
 	if (ret < 0) {
-		dev_err(&client->dev, "Write to device fails status %x\n", ret);
 		return ret;
 	}
-	data->reg_cache[reg] = regval;
+	data->cntl_cache = regval;
+	/* After mode change wait atleast 100us */
+	usleep_range(100, 500);
 
 	return 0;
 }
@@ -207,18 +343,15 @@ static int ak8975_setup(struct i2c_client *client)
 	}
 
 	/* Write the fused rom access mode. */
-	ret = ak8975_write_data(client,
-				AK8975_REG_CNTL,
-				AK8975_REG_CNTL_MODE_FUSE_ROM,
-				AK8975_REG_CNTL_MODE_MASK,
-				AK8975_REG_CNTL_MODE_SHIFT);
+	ret = ak8975_set_mode(data, FUSE_ROM);
 	if (ret < 0) {
 		dev_err(&client->dev, "Error in setting fuse access mode\n");
 		return ret;
 	}
 
 	/* Get asa data and store in the device data. */
-	ret = i2c_smbus_read_i2c_block_data(client, AK8975_REG_ASAX,
+	ret = i2c_smbus_read_i2c_block_data(client,
+					    data->def->ctrl_regs[ASA_BASE],
 					    3, data->asa);
 	if (ret < 0) {
 		dev_err(&client->dev, "Not able to read asa data\n");
@@ -226,11 +359,7 @@ static int ak8975_setup(struct i2c_client *client)
 	}
 
 	/* After reading fuse ROM data set power-down mode */
-	ret = ak8975_write_data(client,
-				AK8975_REG_CNTL,
-				AK8975_REG_CNTL_MODE_POWER_DOWN,
-				AK8975_REG_CNTL_MODE_MASK,
-				AK8975_REG_CNTL_MODE_SHIFT);
+	ret = ak8975_set_mode(data, POWER_DOWN);
 	if (ret < 0) {
 		dev_err(&client->dev, "Error in setting power-down mode\n");
 		return ret;
@@ -245,56 +374,9 @@ static int ak8975_setup(struct i2c_client *client)
 		}
 	}
 
-/*
- * Precalculate scale factor (in Gauss units) for each axis and
- * store in the device data.
- *
- * This scale factor is axis-dependent, and is derived from 3 calibration
- * factors ASA(x), ASA(y), and ASA(z).
- *
- * These ASA values are read from the sensor device at start of day, and
- * cached in the device context struct.
- *
- * Adjusting the flux value with the sensitivity adjustment value should be
- * done via the following formula:
- *
- * Hadj = H * ( ( ( (ASA-128)*0.5 ) / 128 ) + 1 )
- *
- * where H is the raw value, ASA is the sensitivity adjustment, and Hadj
- * is the resultant adjusted value.
- *
- * We reduce the formula to:
- *
- * Hadj = H * (ASA + 128) / 256
- *
- * H is in the range of -4096 to 4095.  The magnetometer has a range of
- * +-1229uT.  To go from the raw value to uT is:
- *
- * HuT = H * 1229/4096, or roughly, 3/10.
- *
- * Since 1uT = 0.01 gauss, our final scale factor becomes:
- *
- * Hadj = H * ((ASA + 128) / 256) * 3/10 * 1/100
- * Hadj = H * ((ASA + 128) * 0.003) / 256
- *
- * Since ASA doesn't change, we cache the resultant scale factor into the
- * device context in ak8975_setup().
- */
-	if (data->chipset == AK8963) {
-		/*
-		 * H range is +-8190 and magnetometer range is +-4912.
-		 * So HuT using the above explanation for 8975,
-		 * 4912/8190 = ~ 6/10.
-		 * So the Hadj should use 6/10 instead of 3/10.
-		 */
-		data->raw_to_gauss[0] = RAW_TO_GAUSS_8963(data->asa[0]);
-		data->raw_to_gauss[1] = RAW_TO_GAUSS_8963(data->asa[1]);
-		data->raw_to_gauss[2] = RAW_TO_GAUSS_8963(data->asa[2]);
-	} else {
-		data->raw_to_gauss[0] = RAW_TO_GAUSS_8975(data->asa[0]);
-		data->raw_to_gauss[1] = RAW_TO_GAUSS_8975(data->asa[1]);
-		data->raw_to_gauss[2] = RAW_TO_GAUSS_8975(data->asa[2]);
-	}
+	data->raw_to_gauss[0] = data->def->raw_to_gauss(data->asa[0]);
+	data->raw_to_gauss[1] = data->def->raw_to_gauss(data->asa[1]);
+	data->raw_to_gauss[2] = data->def->raw_to_gauss(data->asa[2]);
 
 	return 0;
 }
@@ -317,7 +399,7 @@ static int wait_conversion_complete_gpio(struct ak8975_data *data)
 		return -EINVAL;
 	}
 
-	ret = i2c_smbus_read_byte_data(client, AK8975_REG_ST1);
+	ret = i2c_smbus_read_byte_data(client, data->def->ctrl_regs[ST1]);
 	if (ret < 0)
 		dev_err(&client->dev, "Error in reading ST1\n");
 
@@ -334,7 +416,8 @@ static int wait_conversion_complete_polled(struct ak8975_data *data)
 	/* Wait for the conversion to complete. */
 	while (timeout_ms) {
 		msleep(AK8975_CONVERSION_DONE_POLL_TIME);
-		ret = i2c_smbus_read_byte_data(client, AK8975_REG_ST1);
+		ret = i2c_smbus_read_byte_data(client,
+				data->def->ctrl_regs[ST1]);
 		if (ret < 0) {
 			dev_err(&client->dev, "Error in reading ST1\n");
 			return ret;
@@ -377,11 +460,7 @@ static int ak8975_read_axis(struct iio_dev *indio_dev, int index, int *val)
 	mutex_lock(&data->lock);
 
 	/* Set up the device for taking a sample. */
-	ret = ak8975_write_data(client,
-				AK8975_REG_CNTL,
-				AK8975_REG_CNTL_MODE_ONCE,
-				AK8975_REG_CNTL_MODE_MASK,
-				AK8975_REG_CNTL_MODE_SHIFT);
+	ret = ak8975_set_mode(data, MODE_ONCE);
 	if (ret < 0) {
 		dev_err(&client->dev, "Error in setting operating mode\n");
 		goto exit;
@@ -398,14 +477,15 @@ static int ak8975_read_axis(struct iio_dev *indio_dev, int index, int *val)
 		goto exit;
 
 	/* This will be executed only for non-interrupt based waiting case */
-	if (ret & AK8975_REG_ST1_DRDY_MASK) {
-		ret = i2c_smbus_read_byte_data(client, AK8975_REG_ST2);
+	if (ret & data->def->ctrl_masks[ST1_DRDY]) {
+		ret = i2c_smbus_read_byte_data(client,
+				data->def->ctrl_regs[ST2]);
 		if (ret < 0) {
 			dev_err(&client->dev, "Error in reading ST2\n");
 			goto exit;
 		}
-		if (ret & (AK8975_REG_ST2_DERR_MASK |
-			   AK8975_REG_ST2_HOFL_MASK)) {
+		if (ret & (data->def->ctrl_masks[ST2_DERR] |
+			   data->def->ctrl_masks[ST2_HOFL])) {
 			dev_err(&client->dev, "ST2 status error 0x%x\n", ret);
 			ret = -EINVAL;
 			goto exit;
@@ -414,7 +494,7 @@ static int ak8975_read_axis(struct iio_dev *indio_dev, int index, int *val)
 
 	/* Read the flux value from the appropriate register
 	   (the register is specified in the iio device attributes). */
-	ret = i2c_smbus_read_word_data(client, ak8975_index_to_reg[index]);
+	ret = i2c_smbus_read_word_data(client, data->def->data_regs[index]);
 	if (ret < 0) {
 		dev_err(&client->dev, "Read axis data fails\n");
 		goto exit;
@@ -423,7 +503,7 @@ static int ak8975_read_axis(struct iio_dev *indio_dev, int index, int *val)
 	mutex_unlock(&data->lock);
 
 	/* Clamp to valid range. */
-	*val = clamp_t(s16, ret, -4096, 4095);
+	*val = clamp_t(s16, ret, -data->def->range, data->def->range);
 	return IIO_VAL_INT;
 
 exit:
@@ -497,6 +577,7 @@ static int ak8975_probe(struct i2c_client *client,
 	int eoc_gpio;
 	int err;
 	const char *name = NULL;
+	enum asahi_compass_chipset chipset;
 
 	/* Grab and set up the supplied GPIO. */
 	if (client->dev.platform_data)
@@ -536,14 +617,20 @@ static int ak8975_probe(struct i2c_client *client,
 
 	/* id will be NULL when enumerated via ACPI */
 	if (id) {
-		data->chipset =
-			(enum asahi_compass_chipset)(id->driver_data);
+		chipset = (enum asahi_compass_chipset)(id->driver_data);
 		name = id->name;
 	} else if (ACPI_HANDLE(&client->dev))
-		name = ak8975_match_acpi_device(&client->dev, &data->chipset);
+		name = ak8975_match_acpi_device(&client->dev, &chipset);
 	else
 		return -ENOSYS;
 
+	if (chipset >= AK_MAX_TYPE) {
+		dev_err(&client->dev, "AKM device type unsupported: %d\n",
+			chipset);
+		return -ENODEV;
+	}
+
+	data->def = &ak_def_array[chipset];
 	dev_dbg(&client->dev, "Asahi compass chip %s\n", name);
 
 	/* Perform some basic start-of-day setup of the device. */
@@ -574,7 +661,9 @@ MODULE_DEVICE_TABLE(i2c, ak8975_id);
 static const struct of_device_id ak8975_of_match[] = {
 	{ .compatible = "asahi-kasei,ak8975", },
 	{ .compatible = "ak8975", },
-	{ }
+	{ .compatible = "asahi-kasei,ak8963", },
+	{ .compatible = "ak8963", },
+	{}
 };
 MODULE_DEVICE_TABLE(of, ak8975_of_match);
 
-- 
2.1.0.rc2.206.gedb03e5

[PATCH v4 2/3] iio: ak8975: add definition structure per compass type

[Gwendal Grignou]

For each type of compass supported (AK8975 and AK8963),
add a definition structure for register masks, important registers,
raw data interpretation.
This change will make integrating new type of devices easier.

Remove i2c register cache. It is only used for one single register.

Signed-off-by: Gwendal Grignou <gwendal@chromium.org>
Tested-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
---
 added static as requested by kbuild test robot.

 drivers/iio/magnetometer/ak8975.c | 281 +++++++++++++++++++++++++-------------
 1 file changed, 186 insertions(+), 95 deletions(-)

diff --git a/drivers/iio/magnetometer/ak8975.c b/drivers/iio/magnetometer/ak8975.c
index 4e69480..3ab984c 100644
--- a/drivers/iio/magnetometer/ak8975.c
+++ b/drivers/iio/magnetometer/ak8975.c
@@ -86,13 +86,155 @@
 #define AK8975_MAX_CONVERSION_TIMEOUT	500
 #define AK8975_CONVERSION_DONE_POLL_TIME 10
 #define AK8975_DATA_READY_TIMEOUT	((100*HZ)/1000)
-#define RAW_TO_GAUSS_8975(asa) ((((asa) + 128) * 3000) / 256)
-#define RAW_TO_GAUSS_8963(asa) ((((asa) + 128) * 6000) / 256)
+
+/*
+ * Precalculate scale factor (in Gauss units) for each axis and
+ * store in the device data.
+ *
+ * This scale factor is axis-dependent, and is derived from 3 calibration
+ * factors ASA(x), ASA(y), and ASA(z).
+ *
+ * These ASA values are read from the sensor device at start of day, and
+ * cached in the device context struct.
+ *
+ * Adjusting the flux value with the sensitivity adjustment value should be
+ * done via the following formula:
+ *
+ * Hadj = H * ( ( ( (ASA-128)*0.5 ) / 128 ) + 1 )
+ * where H is the raw value, ASA is the sensitivity adjustment, and Hadj
+ * is the resultant adjusted value.
+ *
+ * We reduce the formula to:
+ *
+ * Hadj = H * (ASA + 128) / 256
+ *
+ * H is in the range of -4096 to 4095.  The magnetometer has a range of
+ * +-1229uT.  To go from the raw value to uT is:
+ *
+ * HuT = H * 1229/4096, or roughly, 3/10.
+ *
+ * Since 1uT = 0.01 gauss, our final scale factor becomes:
+ *
+ * Hadj = H * ((ASA + 128) / 256) * 3/10 * 1/100
+ * Hadj = H * ((ASA + 128) * 0.003) / 256
+ *
+ * Since ASA doesn't change, we cache the resultant scale factor into the
+ * device context in ak8975_setup().
+ *
+ * Given we use IIO_VAL_INT_PLUS_MICRO bit when displaying the scale, we
+ * multiply the stored scale value by 1e6.
+ */
+static long ak8975_raw_to_gauss(u16 data)
+{
+	return (((long)data + 128) * 3000) / 256;
+}
+
+/*
+ * For AK8963, same calculation, but the device is less sensitive:
+ *
+ * H is in the range of +-8190.  The magnetometer has a range of
+ * +-4912uT.  To go from the raw value to uT is:
+ *
+ * HuT = H * 4912/8190, or roughly, 6/10, instead of 3/10.
+ */
+static long ak8963_raw_to_gauss(u16 data)
+{
+	return (((long)data + 128) * 6000) / 256;
+}
 
 /* Compatible Asahi Kasei Compass parts */
 enum asahi_compass_chipset {
 	AK8975,
 	AK8963,
+	AK_MAX_TYPE
+};
+
+enum ak_ctrl_reg_addr {
+	ST1,
+	ST2,
+	CNTL,
+	ASA_BASE,
+	MAX_REGS,
+	REGS_END,
+};
+
+enum ak_ctrl_reg_mask {
+	ST1_DRDY,
+	ST2_HOFL,
+	ST2_DERR,
+	CNTL_MODE,
+	MASK_END,
+};
+
+enum ak_ctrl_mode {
+	POWER_DOWN,
+	MODE_ONCE,
+	SELF_TEST,
+	FUSE_ROM,
+	MODE_END,
+};
+
+struct ak_def {
+	enum asahi_compass_chipset type;
+	long (*raw_to_gauss)(u16 data);
+	u16 range;
+	u8 ctrl_regs[REGS_END];
+	u8 ctrl_masks[MASK_END];
+	u8 ctrl_modes[MODE_END];
+	u8 data_regs[3];
+};
+
+static struct ak_def ak_def_array[AK_MAX_TYPE] = {
+	{
+		.type = AK8975,
+		.raw_to_gauss = ak8975_raw_to_gauss,
+		.range = 4096,
+		.ctrl_regs = {
+			AK8975_REG_ST1,
+			AK8975_REG_ST2,
+			AK8975_REG_CNTL,
+			AK8975_REG_ASAX,
+			AK8975_MAX_REGS},
+		.ctrl_masks = {
+			AK8975_REG_ST1_DRDY_MASK,
+			AK8975_REG_ST2_HOFL_MASK,
+			AK8975_REG_ST2_DERR_MASK,
+			AK8975_REG_CNTL_MODE_MASK},
+		.ctrl_modes = {
+			AK8975_REG_CNTL_MODE_POWER_DOWN,
+			AK8975_REG_CNTL_MODE_ONCE,
+			AK8975_REG_CNTL_MODE_SELF_TEST,
+			AK8975_REG_CNTL_MODE_FUSE_ROM},
+		.data_regs = {
+			AK8975_REG_HXL,
+			AK8975_REG_HYL,
+			AK8975_REG_HZL},
+	},
+	{
+		.type = AK8963,
+		.raw_to_gauss = ak8963_raw_to_gauss,
+		.range = 8190,
+		.ctrl_regs = {
+			AK8975_REG_ST1,
+			AK8975_REG_ST2,
+			AK8975_REG_CNTL,
+			AK8975_REG_ASAX,
+			AK8975_MAX_REGS},
+		.ctrl_masks = {
+			AK8975_REG_ST1_DRDY_MASK,
+			AK8975_REG_ST2_HOFL_MASK,
+			0,
+			AK8975_REG_CNTL_MODE_MASK},
+		.ctrl_modes = {
+			AK8975_REG_CNTL_MODE_POWER_DOWN,
+			AK8975_REG_CNTL_MODE_ONCE,
+			AK8975_REG_CNTL_MODE_SELF_TEST,
+			AK8975_REG_CNTL_MODE_FUSE_ROM},
+		.data_regs = {
+			AK8975_REG_HXL,
+			AK8975_REG_HYL,
+			AK8975_REG_HZL},
+	},
 };
 
 /*
@@ -100,40 +242,36 @@ enum asahi_compass_chipset {
  */
 struct ak8975_data {
 	struct i2c_client	*client;
+	struct ak_def		*def;
 	struct attribute_group	attrs;
 	struct mutex		lock;
 	u8			asa[3];
 	long			raw_to_gauss[3];
-	u8			reg_cache[AK8975_MAX_REGS];
 	int			eoc_gpio;
 	int			eoc_irq;
 	wait_queue_head_t	data_ready_queue;
 	unsigned long		flags;
-	enum asahi_compass_chipset chipset;
-};
-
-static const int ak8975_index_to_reg[] = {
-	AK8975_REG_HXL, AK8975_REG_HYL, AK8975_REG_HZL,
+	u8			cntl_cache;
 };
 
 /*
- * Helper function to write to the I2C device's registers.
+ * Helper function to write to CNTL register.
  */
-static int ak8975_write_data(struct i2c_client *client,
-			     u8 reg, u8 val, u8 mask, u8 shift)
+static int ak8975_set_mode(struct ak8975_data *data, enum ak_ctrl_mode mode)
 {
-	struct iio_dev *indio_dev = i2c_get_clientdata(client);
-	struct ak8975_data *data = iio_priv(indio_dev);
 	u8 regval;
 	int ret;
 
-	regval = (data->reg_cache[reg] & ~mask) | (val << shift);
-	ret = i2c_smbus_write_byte_data(client, reg, regval);
+	regval = (data->cntl_cache & ~data->def->ctrl_masks[CNTL_MODE]) |
+		 data->def->ctrl_modes[mode];
+	ret = i2c_smbus_write_byte_data(data->client,
+			data->def->ctrl_regs[CNTL], regval);
 	if (ret < 0) {
-		dev_err(&client->dev, "Write to device fails status %x\n", ret);
 		return ret;
 	}
-	data->reg_cache[reg] = regval;
+	data->cntl_cache = regval;
+	/* After mode change wait atleast 100us */
+	usleep_range(100, 500);
 
 	return 0;
 }
@@ -207,18 +345,15 @@ static int ak8975_setup(struct i2c_client *client)
 	}
 
 	/* Write the fused rom access mode. */
-	ret = ak8975_write_data(client,
-				AK8975_REG_CNTL,
-				AK8975_REG_CNTL_MODE_FUSE_ROM,
-				AK8975_REG_CNTL_MODE_MASK,
-				AK8975_REG_CNTL_MODE_SHIFT);
+	ret = ak8975_set_mode(data, FUSE_ROM);
 	if (ret < 0) {
 		dev_err(&client->dev, "Error in setting fuse access mode\n");
 		return ret;
 	}
 
 	/* Get asa data and store in the device data. */
-	ret = i2c_smbus_read_i2c_block_data(client, AK8975_REG_ASAX,
+	ret = i2c_smbus_read_i2c_block_data(client,
+					    data->def->ctrl_regs[ASA_BASE],
 					    3, data->asa);
 	if (ret < 0) {
 		dev_err(&client->dev, "Not able to read asa data\n");
@@ -226,11 +361,7 @@ static int ak8975_setup(struct i2c_client *client)
 	}
 
 	/* After reading fuse ROM data set power-down mode */
-	ret = ak8975_write_data(client,
-				AK8975_REG_CNTL,
-				AK8975_REG_CNTL_MODE_POWER_DOWN,
-				AK8975_REG_CNTL_MODE_MASK,
-				AK8975_REG_CNTL_MODE_SHIFT);
+	ret = ak8975_set_mode(data, POWER_DOWN);
 	if (ret < 0) {
 		dev_err(&client->dev, "Error in setting power-down mode\n");
 		return ret;
@@ -245,56 +376,9 @@ static int ak8975_setup(struct i2c_client *client)
 		}
 	}
 
-/*
- * Precalculate scale factor (in Gauss units) for each axis and
- * store in the device data.
- *
- * This scale factor is axis-dependent, and is derived from 3 calibration
- * factors ASA(x), ASA(y), and ASA(z).
- *
- * These ASA values are read from the sensor device at start of day, and
- * cached in the device context struct.
- *
- * Adjusting the flux value with the sensitivity adjustment value should be
- * done via the following formula:
- *
- * Hadj = H * ( ( ( (ASA-128)*0.5 ) / 128 ) + 1 )
- *
- * where H is the raw value, ASA is the sensitivity adjustment, and Hadj
- * is the resultant adjusted value.
- *
- * We reduce the formula to:
- *
- * Hadj = H * (ASA + 128) / 256
- *
- * H is in the range of -4096 to 4095.  The magnetometer has a range of
- * +-1229uT.  To go from the raw value to uT is:
- *
- * HuT = H * 1229/4096, or roughly, 3/10.
- *
- * Since 1uT = 0.01 gauss, our final scale factor becomes:
- *
- * Hadj = H * ((ASA + 128) / 256) * 3/10 * 1/100
- * Hadj = H * ((ASA + 128) * 0.003) / 256
- *
- * Since ASA doesn't change, we cache the resultant scale factor into the
- * device context in ak8975_setup().
- */
-	if (data->chipset == AK8963) {
-		/*
-		 * H range is +-8190 and magnetometer range is +-4912.
-		 * So HuT using the above explanation for 8975,
-		 * 4912/8190 = ~ 6/10.
-		 * So the Hadj should use 6/10 instead of 3/10.
-		 */
-		data->raw_to_gauss[0] = RAW_TO_GAUSS_8963(data->asa[0]);
-		data->raw_to_gauss[1] = RAW_TO_GAUSS_8963(data->asa[1]);
-		data->raw_to_gauss[2] = RAW_TO_GAUSS_8963(data->asa[2]);
-	} else {
-		data->raw_to_gauss[0] = RAW_TO_GAUSS_8975(data->asa[0]);
-		data->raw_to_gauss[1] = RAW_TO_GAUSS_8975(data->asa[1]);
-		data->raw_to_gauss[2] = RAW_TO_GAUSS_8975(data->asa[2]);
-	}
+	data->raw_to_gauss[0] = data->def->raw_to_gauss(data->asa[0]);
+	data->raw_to_gauss[1] = data->def->raw_to_gauss(data->asa[1]);
+	data->raw_to_gauss[2] = data->def->raw_to_gauss(data->asa[2]);
 
 	return 0;
 }
@@ -317,7 +401,7 @@ static int wait_conversion_complete_gpio(struct ak8975_data *data)
 		return -EINVAL;
 	}
 
-	ret = i2c_smbus_read_byte_data(client, AK8975_REG_ST1);
+	ret = i2c_smbus_read_byte_data(client, data->def->ctrl_regs[ST1]);
 	if (ret < 0)
 		dev_err(&client->dev, "Error in reading ST1\n");
 
@@ -334,7 +418,8 @@ static int wait_conversion_complete_polled(struct ak8975_data *data)
 	/* Wait for the conversion to complete. */
 	while (timeout_ms) {
 		msleep(AK8975_CONVERSION_DONE_POLL_TIME);
-		ret = i2c_smbus_read_byte_data(client, AK8975_REG_ST1);
+		ret = i2c_smbus_read_byte_data(client,
+				data->def->ctrl_regs[ST1]);
 		if (ret < 0) {
 			dev_err(&client->dev, "Error in reading ST1\n");
 			return ret;
@@ -377,11 +462,7 @@ static int ak8975_read_axis(struct iio_dev *indio_dev, int index, int *val)
 	mutex_lock(&data->lock);
 
 	/* Set up the device for taking a sample. */
-	ret = ak8975_write_data(client,
-				AK8975_REG_CNTL,
-				AK8975_REG_CNTL_MODE_ONCE,
-				AK8975_REG_CNTL_MODE_MASK,
-				AK8975_REG_CNTL_MODE_SHIFT);
+	ret = ak8975_set_mode(data, MODE_ONCE);
 	if (ret < 0) {
 		dev_err(&client->dev, "Error in setting operating mode\n");
 		goto exit;
@@ -398,14 +479,15 @@ static int ak8975_read_axis(struct iio_dev *indio_dev, int index, int *val)
 		goto exit;
 
 	/* This will be executed only for non-interrupt based waiting case */
-	if (ret & AK8975_REG_ST1_DRDY_MASK) {
-		ret = i2c_smbus_read_byte_data(client, AK8975_REG_ST2);
+	if (ret & data->def->ctrl_masks[ST1_DRDY]) {
+		ret = i2c_smbus_read_byte_data(client,
+				data->def->ctrl_regs[ST2]);
 		if (ret < 0) {
 			dev_err(&client->dev, "Error in reading ST2\n");
 			goto exit;
 		}
-		if (ret & (AK8975_REG_ST2_DERR_MASK |
-			   AK8975_REG_ST2_HOFL_MASK)) {
+		if (ret & (data->def->ctrl_masks[ST2_DERR] |
+			   data->def->ctrl_masks[ST2_HOFL])) {
 			dev_err(&client->dev, "ST2 status error 0x%x\n", ret);
 			ret = -EINVAL;
 			goto exit;
@@ -414,7 +496,7 @@ static int ak8975_read_axis(struct iio_dev *indio_dev, int index, int *val)
 
 	/* Read the flux value from the appropriate register
 	   (the register is specified in the iio device attributes). */
-	ret = i2c_smbus_read_word_data(client, ak8975_index_to_reg[index]);
+	ret = i2c_smbus_read_word_data(client, data->def->data_regs[index]);
 	if (ret < 0) {
 		dev_err(&client->dev, "Read axis data fails\n");
 		goto exit;
@@ -423,7 +505,7 @@ static int ak8975_read_axis(struct iio_dev *indio_dev, int index, int *val)
 	mutex_unlock(&data->lock);
 
 	/* Clamp to valid range. */
-	*val = clamp_t(s16, ret, -4096, 4095);
+	*val = clamp_t(s16, ret, -data->def->range, data->def->range);
 	return IIO_VAL_INT;
 
 exit:
@@ -497,6 +579,7 @@ static int ak8975_probe(struct i2c_client *client,
 	int eoc_gpio;
 	int err;
 	const char *name = NULL;
+	enum asahi_compass_chipset chipset;
 
 	/* Grab and set up the supplied GPIO. */
 	if (client->dev.platform_data)
@@ -536,14 +619,20 @@ static int ak8975_probe(struct i2c_client *client,
 
 	/* id will be NULL when enumerated via ACPI */
 	if (id) {
-		data->chipset =
-			(enum asahi_compass_chipset)(id->driver_data);
+		chipset = (enum asahi_compass_chipset)(id->driver_data);
 		name = id->name;
 	} else if (ACPI_HANDLE(&client->dev))
-		name = ak8975_match_acpi_device(&client->dev, &data->chipset);
+		name = ak8975_match_acpi_device(&client->dev, &chipset);
 	else
 		return -ENOSYS;
 
+	if (chipset >= AK_MAX_TYPE) {
+		dev_err(&client->dev, "AKM device type unsupported: %d\n",
+			chipset);
+		return -ENODEV;
+	}
+
+	data->def = &ak_def_array[chipset];
 	dev_dbg(&client->dev, "Asahi compass chip %s\n", name);
 
 	/* Perform some basic start-of-day setup of the device. */
@@ -574,7 +663,9 @@ MODULE_DEVICE_TABLE(i2c, ak8975_id);
 static const struct of_device_id ak8975_of_match[] = {
 	{ .compatible = "asahi-kasei,ak8975", },
 	{ .compatible = "ak8975", },
-	{ }
+	{ .compatible = "asahi-kasei,ak8963", },
+	{ .compatible = "ak8963", },
+	{}
 };
 MODULE_DEVICE_TABLE(of, ak8975_of_match);
 
-- 
2.1.0.rc2.206.gedb03e5

Re: [PATCH v4 2/3] iio: ak8975: add definition structure per compass type

[Hartmut Knaack]

Gwendal Grignou schrieb am 24.11.2014 um 09:43:
> For each type of compass supported (AK8975 and AK8963),
> add a definition structure for register masks, important registers,
> raw data interpretation.
> This change will make integrating new type of devices easier.
> 
> Remove i2c register cache. It is only used for one single register.
> 
> Signed-off-by: Gwendal Grignou <gwendal@chromium.org>
> Tested-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Reviewed-by: Hartmut Knaack <knaack.h@gmx.de>
> ---
>  added static as requested by kbuild test robot.
> 
Looking good overall. Only minor style nitpicking remaining is about
some introduced instances of i2c_smbus_write_byte_data and
i2c_smbus_read_byte_data, where the second line of parameters should
be aligned with the opening parenthesis. But that's no showstopper.
>  drivers/iio/magnetometer/ak8975.c | 281 +++++++++++++++++++++++++-------------
>  1 file changed, 186 insertions(+), 95 deletions(-)
> 
> diff --git a/drivers/iio/magnetometer/ak8975.c b/drivers/iio/magnetometer/ak8975.c
> index 4e69480..3ab984c 100644
> --- a/drivers/iio/magnetometer/ak8975.c
> +++ b/drivers/iio/magnetometer/ak8975.c
> @@ -86,13 +86,155 @@
>  #define AK8975_MAX_CONVERSION_TIMEOUT	500
>  #define AK8975_CONVERSION_DONE_POLL_TIME 10
>  #define AK8975_DATA_READY_TIMEOUT	((100*HZ)/1000)
> -#define RAW_TO_GAUSS_8975(asa) ((((asa) + 128) * 3000) / 256)
> -#define RAW_TO_GAUSS_8963(asa) ((((asa) + 128) * 6000) / 256)
> +
> +/*
> + * Precalculate scale factor (in Gauss units) for each axis and
> + * store in the device data.
> + *
> + * This scale factor is axis-dependent, and is derived from 3 calibration
> + * factors ASA(x), ASA(y), and ASA(z).
> + *
> + * These ASA values are read from the sensor device at start of day, and
> + * cached in the device context struct.
> + *
> + * Adjusting the flux value with the sensitivity adjustment value should be
> + * done via the following formula:
> + *
> + * Hadj = H * ( ( ( (ASA-128)*0.5 ) / 128 ) + 1 )
> + * where H is the raw value, ASA is the sensitivity adjustment, and Hadj
> + * is the resultant adjusted value.
> + *
> + * We reduce the formula to:
> + *
> + * Hadj = H * (ASA + 128) / 256
> + *
> + * H is in the range of -4096 to 4095.  The magnetometer has a range of
> + * +-1229uT.  To go from the raw value to uT is:
> + *
> + * HuT = H * 1229/4096, or roughly, 3/10.
> + *
> + * Since 1uT = 0.01 gauss, our final scale factor becomes:
> + *
> + * Hadj = H * ((ASA + 128) / 256) * 3/10 * 1/100
> + * Hadj = H * ((ASA + 128) * 0.003) / 256
> + *
> + * Since ASA doesn't change, we cache the resultant scale factor into the
> + * device context in ak8975_setup().
> + *
> + * Given we use IIO_VAL_INT_PLUS_MICRO bit when displaying the scale, we
> + * multiply the stored scale value by 1e6.
> + */
> +static long ak8975_raw_to_gauss(u16 data)
> +{
> +	return (((long)data + 128) * 3000) / 256;
> +}
> +
> +/*
> + * For AK8963, same calculation, but the device is less sensitive:
> + *
> + * H is in the range of +-8190.  The magnetometer has a range of
> + * +-4912uT.  To go from the raw value to uT is:
> + *
> + * HuT = H * 4912/8190, or roughly, 6/10, instead of 3/10.
> + */
> +static long ak8963_raw_to_gauss(u16 data)
> +{
> +	return (((long)data + 128) * 6000) / 256;
> +}
>  
>  /* Compatible Asahi Kasei Compass parts */
>  enum asahi_compass_chipset {
>  	AK8975,
>  	AK8963,
> +	AK_MAX_TYPE
> +};
> +
> +enum ak_ctrl_reg_addr {
> +	ST1,
> +	ST2,
> +	CNTL,
> +	ASA_BASE,
> +	MAX_REGS,
> +	REGS_END,
> +};
> +
> +enum ak_ctrl_reg_mask {
> +	ST1_DRDY,
> +	ST2_HOFL,
> +	ST2_DERR,
> +	CNTL_MODE,
> +	MASK_END,
> +};
> +
> +enum ak_ctrl_mode {
> +	POWER_DOWN,
> +	MODE_ONCE,
> +	SELF_TEST,
> +	FUSE_ROM,
> +	MODE_END,
> +};
> +
> +struct ak_def {
> +	enum asahi_compass_chipset type;
> +	long (*raw_to_gauss)(u16 data);
> +	u16 range;
> +	u8 ctrl_regs[REGS_END];
> +	u8 ctrl_masks[MASK_END];
> +	u8 ctrl_modes[MODE_END];
> +	u8 data_regs[3];
> +};
> +
> +static struct ak_def ak_def_array[AK_MAX_TYPE] = {
> +	{
> +		.type = AK8975,
> +		.raw_to_gauss = ak8975_raw_to_gauss,
> +		.range = 4096,
> +		.ctrl_regs = {
> +			AK8975_REG_ST1,
> +			AK8975_REG_ST2,
> +			AK8975_REG_CNTL,
> +			AK8975_REG_ASAX,
> +			AK8975_MAX_REGS},
> +		.ctrl_masks = {
> +			AK8975_REG_ST1_DRDY_MASK,
> +			AK8975_REG_ST2_HOFL_MASK,
> +			AK8975_REG_ST2_DERR_MASK,
> +			AK8975_REG_CNTL_MODE_MASK},
> +		.ctrl_modes = {
> +			AK8975_REG_CNTL_MODE_POWER_DOWN,
> +			AK8975_REG_CNTL_MODE_ONCE,
> +			AK8975_REG_CNTL_MODE_SELF_TEST,
> +			AK8975_REG_CNTL_MODE_FUSE_ROM},
> +		.data_regs = {
> +			AK8975_REG_HXL,
> +			AK8975_REG_HYL,
> +			AK8975_REG_HZL},
> +	},
> +	{
> +		.type = AK8963,
> +		.raw_to_gauss = ak8963_raw_to_gauss,
> +		.range = 8190,
> +		.ctrl_regs = {
> +			AK8975_REG_ST1,
> +			AK8975_REG_ST2,
> +			AK8975_REG_CNTL,
> +			AK8975_REG_ASAX,
> +			AK8975_MAX_REGS},
> +		.ctrl_masks = {
> +			AK8975_REG_ST1_DRDY_MASK,
> +			AK8975_REG_ST2_HOFL_MASK,
> +			0,
> +			AK8975_REG_CNTL_MODE_MASK},
> +		.ctrl_modes = {
> +			AK8975_REG_CNTL_MODE_POWER_DOWN,
> +			AK8975_REG_CNTL_MODE_ONCE,
> +			AK8975_REG_CNTL_MODE_SELF_TEST,
> +			AK8975_REG_CNTL_MODE_FUSE_ROM},
> +		.data_regs = {
> +			AK8975_REG_HXL,
> +			AK8975_REG_HYL,
> +			AK8975_REG_HZL},
> +	},
>  };
>  
>  /*
> @@ -100,40 +242,36 @@ enum asahi_compass_chipset {
>   */
>  struct ak8975_data {
>  	struct i2c_client	*client;
> +	struct ak_def		*def;
>  	struct attribute_group	attrs;
>  	struct mutex		lock;
>  	u8			asa[3];
>  	long			raw_to_gauss[3];
> -	u8			reg_cache[AK8975_MAX_REGS];
>  	int			eoc_gpio;
>  	int			eoc_irq;
>  	wait_queue_head_t	data_ready_queue;
>  	unsigned long		flags;
> -	enum asahi_compass_chipset chipset;
> -};
> -
> -static const int ak8975_index_to_reg[] = {
> -	AK8975_REG_HXL, AK8975_REG_HYL, AK8975_REG_HZL,
> +	u8			cntl_cache;
>  };
>  
>  /*
> - * Helper function to write to the I2C device's registers.
> + * Helper function to write to CNTL register.
>   */
> -static int ak8975_write_data(struct i2c_client *client,
> -			     u8 reg, u8 val, u8 mask, u8 shift)
> +static int ak8975_set_mode(struct ak8975_data *data, enum ak_ctrl_mode mode)
>  {
> -	struct iio_dev *indio_dev = i2c_get_clientdata(client);
> -	struct ak8975_data *data = iio_priv(indio_dev);
>  	u8 regval;
>  	int ret;
>  
> -	regval = (data->reg_cache[reg] & ~mask) | (val << shift);
> -	ret = i2c_smbus_write_byte_data(client, reg, regval);
> +	regval = (data->cntl_cache & ~data->def->ctrl_masks[CNTL_MODE]) |
> +		 data->def->ctrl_modes[mode];
> +	ret = i2c_smbus_write_byte_data(data->client,
> +			data->def->ctrl_regs[CNTL], regval);
>  	if (ret < 0) {
> -		dev_err(&client->dev, "Write to device fails status %x\n", ret);
>  		return ret;
>  	}
> -	data->reg_cache[reg] = regval;
> +	data->cntl_cache = regval;
> +	/* After mode change wait atleast 100us */
> +	usleep_range(100, 500);
>  
>  	return 0;
>  }
> @@ -207,18 +345,15 @@ static int ak8975_setup(struct i2c_client *client)
>  	}
>  
>  	/* Write the fused rom access mode. */
> -	ret = ak8975_write_data(client,
> -				AK8975_REG_CNTL,
> -				AK8975_REG_CNTL_MODE_FUSE_ROM,
> -				AK8975_REG_CNTL_MODE_MASK,
> -				AK8975_REG_CNTL_MODE_SHIFT);
> +	ret = ak8975_set_mode(data, FUSE_ROM);
>  	if (ret < 0) {
>  		dev_err(&client->dev, "Error in setting fuse access mode\n");
>  		return ret;
>  	}
>  
>  	/* Get asa data and store in the device data. */
> -	ret = i2c_smbus_read_i2c_block_data(client, AK8975_REG_ASAX,
> +	ret = i2c_smbus_read_i2c_block_data(client,
> +					    data->def->ctrl_regs[ASA_BASE],
>  					    3, data->asa);
>  	if (ret < 0) {
>  		dev_err(&client->dev, "Not able to read asa data\n");
> @@ -226,11 +361,7 @@ static int ak8975_setup(struct i2c_client *client)
>  	}
>  
>  	/* After reading fuse ROM data set power-down mode */
> -	ret = ak8975_write_data(client,
> -				AK8975_REG_CNTL,
> -				AK8975_REG_CNTL_MODE_POWER_DOWN,
> -				AK8975_REG_CNTL_MODE_MASK,
> -				AK8975_REG_CNTL_MODE_SHIFT);
> +	ret = ak8975_set_mode(data, POWER_DOWN);
>  	if (ret < 0) {
>  		dev_err(&client->dev, "Error in setting power-down mode\n");
>  		return ret;
> @@ -245,56 +376,9 @@ static int ak8975_setup(struct i2c_client *client)
>  		}
>  	}
>  
> -/*
> - * Precalculate scale factor (in Gauss units) for each axis and
> - * store in the device data.
> - *
> - * This scale factor is axis-dependent, and is derived from 3 calibration
> - * factors ASA(x), ASA(y), and ASA(z).
> - *
> - * These ASA values are read from the sensor device at start of day, and
> - * cached in the device context struct.
> - *
> - * Adjusting the flux value with the sensitivity adjustment value should be
> - * done via the following formula:
> - *
> - * Hadj = H * ( ( ( (ASA-128)*0.5 ) / 128 ) + 1 )
> - *
> - * where H is the raw value, ASA is the sensitivity adjustment, and Hadj
> - * is the resultant adjusted value.
> - *
> - * We reduce the formula to:
> - *
> - * Hadj = H * (ASA + 128) / 256
> - *
> - * H is in the range of -4096 to 4095.  The magnetometer has a range of
> - * +-1229uT.  To go from the raw value to uT is:
> - *
> - * HuT = H * 1229/4096, or roughly, 3/10.
> - *
> - * Since 1uT = 0.01 gauss, our final scale factor becomes:
> - *
> - * Hadj = H * ((ASA + 128) / 256) * 3/10 * 1/100
> - * Hadj = H * ((ASA + 128) * 0.003) / 256
> - *
> - * Since ASA doesn't change, we cache the resultant scale factor into the
> - * device context in ak8975_setup().
> - */
> -	if (data->chipset == AK8963) {
> -		/*
> -		 * H range is +-8190 and magnetometer range is +-4912.
> -		 * So HuT using the above explanation for 8975,
> -		 * 4912/8190 = ~ 6/10.
> -		 * So the Hadj should use 6/10 instead of 3/10.
> -		 */
> -		data->raw_to_gauss[0] = RAW_TO_GAUSS_8963(data->asa[0]);
> -		data->raw_to_gauss[1] = RAW_TO_GAUSS_8963(data->asa[1]);
> -		data->raw_to_gauss[2] = RAW_TO_GAUSS_8963(data->asa[2]);
> -	} else {
> -		data->raw_to_gauss[0] = RAW_TO_GAUSS_8975(data->asa[0]);
> -		data->raw_to_gauss[1] = RAW_TO_GAUSS_8975(data->asa[1]);
> -		data->raw_to_gauss[2] = RAW_TO_GAUSS_8975(data->asa[2]);
> -	}
> +	data->raw_to_gauss[0] = data->def->raw_to_gauss(data->asa[0]);
> +	data->raw_to_gauss[1] = data->def->raw_to_gauss(data->asa[1]);
> +	data->raw_to_gauss[2] = data->def->raw_to_gauss(data->asa[2]);
>  
>  	return 0;
>  }
> @@ -317,7 +401,7 @@ static int wait_conversion_complete_gpio(struct ak8975_data *data)
>  		return -EINVAL;
>  	}
>  
> -	ret = i2c_smbus_read_byte_data(client, AK8975_REG_ST1);
> +	ret = i2c_smbus_read_byte_data(client, data->def->ctrl_regs[ST1]);
>  	if (ret < 0)
>  		dev_err(&client->dev, "Error in reading ST1\n");
>  
> @@ -334,7 +418,8 @@ static int wait_conversion_complete_polled(struct ak8975_data *data)
>  	/* Wait for the conversion to complete. */
>  	while (timeout_ms) {
>  		msleep(AK8975_CONVERSION_DONE_POLL_TIME);
> -		ret = i2c_smbus_read_byte_data(client, AK8975_REG_ST1);
> +		ret = i2c_smbus_read_byte_data(client,
> +				data->def->ctrl_regs[ST1]);
>  		if (ret < 0) {
>  			dev_err(&client->dev, "Error in reading ST1\n");
>  			return ret;
> @@ -377,11 +462,7 @@ static int ak8975_read_axis(struct iio_dev *indio_dev, int index, int *val)
>  	mutex_lock(&data->lock);
>  
>  	/* Set up the device for taking a sample. */
> -	ret = ak8975_write_data(client,
> -				AK8975_REG_CNTL,
> -				AK8975_REG_CNTL_MODE_ONCE,
> -				AK8975_REG_CNTL_MODE_MASK,
> -				AK8975_REG_CNTL_MODE_SHIFT);
> +	ret = ak8975_set_mode(data, MODE_ONCE);
>  	if (ret < 0) {
>  		dev_err(&client->dev, "Error in setting operating mode\n");
>  		goto exit;
> @@ -398,14 +479,15 @@ static int ak8975_read_axis(struct iio_dev *indio_dev, int index, int *val)
>  		goto exit;
>  
>  	/* This will be executed only for non-interrupt based waiting case */
> -	if (ret & AK8975_REG_ST1_DRDY_MASK) {
> -		ret = i2c_smbus_read_byte_data(client, AK8975_REG_ST2);
> +	if (ret & data->def->ctrl_masks[ST1_DRDY]) {
> +		ret = i2c_smbus_read_byte_data(client,
> +				data->def->ctrl_regs[ST2]);
>  		if (ret < 0) {
>  			dev_err(&client->dev, "Error in reading ST2\n");
>  			goto exit;
>  		}
> -		if (ret & (AK8975_REG_ST2_DERR_MASK |
> -			   AK8975_REG_ST2_HOFL_MASK)) {
> +		if (ret & (data->def->ctrl_masks[ST2_DERR] |
> +			   data->def->ctrl_masks[ST2_HOFL])) {
>  			dev_err(&client->dev, "ST2 status error 0x%x\n", ret);
>  			ret = -EINVAL;
>  			goto exit;
> @@ -414,7 +496,7 @@ static int ak8975_read_axis(struct iio_dev *indio_dev, int index, int *val)
>  
>  	/* Read the flux value from the appropriate register
>  	   (the register is specified in the iio device attributes). */
> -	ret = i2c_smbus_read_word_data(client, ak8975_index_to_reg[index]);
> +	ret = i2c_smbus_read_word_data(client, data->def->data_regs[index]);
>  	if (ret < 0) {
>  		dev_err(&client->dev, "Read axis data fails\n");
>  		goto exit;
> @@ -423,7 +505,7 @@ static int ak8975_read_axis(struct iio_dev *indio_dev, int index, int *val)
>  	mutex_unlock(&data->lock);
>  
>  	/* Clamp to valid range. */
> -	*val = clamp_t(s16, ret, -4096, 4095);
> +	*val = clamp_t(s16, ret, -data->def->range, data->def->range);
>  	return IIO_VAL_INT;
>  
>  exit:
> @@ -497,6 +579,7 @@ static int ak8975_probe(struct i2c_client *client,
>  	int eoc_gpio;
>  	int err;
>  	const char *name = NULL;
> +	enum asahi_compass_chipset chipset;
>  
>  	/* Grab and set up the supplied GPIO. */
>  	if (client->dev.platform_data)
> @@ -536,14 +619,20 @@ static int ak8975_probe(struct i2c_client *client,
>  
>  	/* id will be NULL when enumerated via ACPI */
>  	if (id) {
> -		data->chipset =
> -			(enum asahi_compass_chipset)(id->driver_data);
> +		chipset = (enum asahi_compass_chipset)(id->driver_data);
>  		name = id->name;
>  	} else if (ACPI_HANDLE(&client->dev))
> -		name = ak8975_match_acpi_device(&client->dev, &data->chipset);
> +		name = ak8975_match_acpi_device(&client->dev, &chipset);
>  	else
>  		return -ENOSYS;
>  
> +	if (chipset >= AK_MAX_TYPE) {
> +		dev_err(&client->dev, "AKM device type unsupported: %d\n",
> +			chipset);
> +		return -ENODEV;
> +	}
> +
> +	data->def = &ak_def_array[chipset];
>  	dev_dbg(&client->dev, "Asahi compass chip %s\n", name);
>  
>  	/* Perform some basic start-of-day setup of the device. */
> @@ -574,7 +663,9 @@ MODULE_DEVICE_TABLE(i2c, ak8975_id);
>  static const struct of_device_id ak8975_of_match[] = {
>  	{ .compatible = "asahi-kasei,ak8975", },
>  	{ .compatible = "ak8975", },
> -	{ }
> +	{ .compatible = "asahi-kasei,ak8963", },
> +	{ .compatible = "ak8963", },
> +	{}
>  };
>  MODULE_DEVICE_TABLE(of, ak8975_of_match);
>  
> 

[PATCH v4 3/3] iio: ak8975: add ak09911 and ak09912 support

[Gwendal Grignou]

Add 2 new definition entries to support ak0991x compass.
Add a more advanced function to check we are dealing with the
expected device.
Remove standalone driver for ak09911.

Tested-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Gwendal Grignou <gwendal@chromium.org>
---
 drivers/iio/magnetometer/Kconfig   |  15 +-
 drivers/iio/magnetometer/Makefile  |   1 -
 drivers/iio/magnetometer/ak09911.c | 326 -------------------------------------
 drivers/iio/magnetometer/ak8975.c  | 195 ++++++++++++++++++++--
 4 files changed, 184 insertions(+), 353 deletions(-)
 delete mode 100644 drivers/iio/magnetometer/ak09911.c

diff --git a/drivers/iio/magnetometer/Kconfig b/drivers/iio/magnetometer/Kconfig
index b2dba9e..4c7a4c5 100644
--- a/drivers/iio/magnetometer/Kconfig
+++ b/drivers/iio/magnetometer/Kconfig
@@ -6,26 +6,21 @@
 menu "Magnetometer sensors"
 
 config AK8975
-	tristate "Asahi Kasei AK8975 3-Axis Magnetometer"
+	tristate "Asahi Kasei AK 3-Axis Magnetometer"
 	depends on I2C
 	depends on GPIOLIB
 	help
-	  Say yes here to build support for Asahi Kasei AK8975 3-Axis
-	  Magnetometer. This driver can also support AK8963, if i2c
-	  device name is identified as ak8963.
+	  Say yes here to build support for Asahi Kasei AK8975, AK8963,
+	  AK09911 or AK09912 3-Axis Magnetometer.
 
 	  To compile this driver as a module, choose M here: the module
 	  will be called ak8975.
 
 config AK09911
 	tristate "Asahi Kasei AK09911 3-axis Compass"
-	depends on I2C
+	select AK8975
 	help
-	  Say yes here to build support for Asahi Kasei AK09911 3-Axis
-	  Magnetometer.
-
-	  To compile this driver as a module, choose M here: the module
-	  will be called ak09911.
+	  Deprecated: AK09911 is now supported by AK8975 driver.
 
 config MAG3110
 	tristate "Freescale MAG3110 3-Axis Magnetometer"
diff --git a/drivers/iio/magnetometer/Makefile b/drivers/iio/magnetometer/Makefile
index b91315e..0f5d3c9 100644
--- a/drivers/iio/magnetometer/Makefile
+++ b/drivers/iio/magnetometer/Makefile
@@ -3,7 +3,6 @@
 #
 
 # When adding new entries keep the list in alphabetical order
-obj-$(CONFIG_AK09911)	+= ak09911.o
 obj-$(CONFIG_AK8975)	+= ak8975.o
 obj-$(CONFIG_MAG3110)	+= mag3110.o
 obj-$(CONFIG_HID_SENSOR_MAGNETOMETER_3D) += hid-sensor-magn-3d.o
diff --git a/drivers/iio/magnetometer/ak09911.c b/drivers/iio/magnetometer/ak09911.c
deleted file mode 100644
index b2bc942..0000000
--- a/drivers/iio/magnetometer/ak09911.c
+++ /dev/null
@@ -1,326 +0,0 @@
-/*
- * AK09911 3-axis compass driver
- * Copyright (c) 2014, Intel Corporation.
- *
- * This program is free software; you can redistribute it and/or modify it
- * under the terms and conditions of the GNU General Public License,
- * version 2, as published by the Free Software Foundation.
- *
- * This program is distributed in the hope it will be useful, but WITHOUT
- * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
- * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
- * more details.
- */
-
-#include <linux/kernel.h>
-#include <linux/module.h>
-#include <linux/init.h>
-#include <linux/types.h>
-#include <linux/slab.h>
-#include <linux/delay.h>
-#include <linux/i2c.h>
-#include <linux/acpi.h>
-#include <linux/iio/iio.h>
-
-#define AK09911_REG_WIA1		0x00
-#define AK09911_REG_WIA2		0x01
-#define AK09911_WIA1_VALUE		0x48
-#define AK09911_WIA2_VALUE		0x05
-
-#define AK09911_REG_ST1			0x10
-#define AK09911_REG_HXL			0x11
-#define AK09911_REG_HXH			0x12
-#define AK09911_REG_HYL			0x13
-#define AK09911_REG_HYH			0x14
-#define AK09911_REG_HZL			0x15
-#define AK09911_REG_HZH			0x16
-
-#define AK09911_REG_ASAX		0x60
-#define AK09911_REG_ASAY		0x61
-#define AK09911_REG_ASAZ		0x62
-
-#define AK09911_REG_CNTL1		0x30
-#define AK09911_REG_CNTL2		0x31
-#define AK09911_REG_CNTL3		0x32
-
-#define AK09911_MODE_SNG_MEASURE	0x01
-#define AK09911_MODE_SELF_TEST		0x10
-#define AK09911_MODE_FUSE_ACCESS	0x1F
-#define AK09911_MODE_POWERDOWN		0x00
-#define AK09911_RESET_DATA		0x01
-
-#define AK09911_REG_CNTL1		0x30
-#define AK09911_REG_CNTL2		0x31
-#define AK09911_REG_CNTL3		0x32
-
-#define AK09911_RAW_TO_GAUSS(asa)	((((asa) + 128) * 6000) / 256)
-
-#define AK09911_MAX_CONVERSION_TIMEOUT_MS	500
-#define AK09911_CONVERSION_DONE_POLL_TIME_MS	10
-
-struct ak09911_data {
-	struct i2c_client	*client;
-	struct mutex		lock;
-	u8			asa[3];
-	long			raw_to_gauss[3];
-};
-
-static const int ak09911_index_to_reg[] = {
-	AK09911_REG_HXL, AK09911_REG_HYL, AK09911_REG_HZL,
-};
-
-static int ak09911_set_mode(struct i2c_client *client, u8 mode)
-{
-	int ret;
-
-	switch (mode) {
-	case AK09911_MODE_SNG_MEASURE:
-	case AK09911_MODE_SELF_TEST:
-	case AK09911_MODE_FUSE_ACCESS:
-	case AK09911_MODE_POWERDOWN:
-		ret = i2c_smbus_write_byte_data(client,
-						AK09911_REG_CNTL2, mode);
-		if (ret < 0) {
-			dev_err(&client->dev, "set_mode error\n");
-			return ret;
-		}
-		/* After mode change wait atleast 100us */
-		usleep_range(100, 500);
-		break;
-	default:
-		dev_err(&client->dev,
-			"%s: Unknown mode(%d).", __func__, mode);
-		return -EINVAL;
-	}
-
-	return ret;
-}
-
-/* Get Sensitivity Adjustment value */
-static int ak09911_get_asa(struct i2c_client *client)
-{
-	struct iio_dev *indio_dev = i2c_get_clientdata(client);
-	struct ak09911_data *data = iio_priv(indio_dev);
-	int ret;
-
-	ret = ak09911_set_mode(client, AK09911_MODE_FUSE_ACCESS);
-	if (ret < 0)
-		return ret;
-
-	/* Get asa data and store in the device data. */
-	ret = i2c_smbus_read_i2c_block_data(client, AK09911_REG_ASAX,
-					    3, data->asa);
-	if (ret < 0) {
-		dev_err(&client->dev, "Not able to read asa data\n");
-		return ret;
-	}
-
-	ret = ak09911_set_mode(client,  AK09911_MODE_POWERDOWN);
-	if (ret < 0)
-		return ret;
-
-	data->raw_to_gauss[0] = AK09911_RAW_TO_GAUSS(data->asa[0]);
-	data->raw_to_gauss[1] = AK09911_RAW_TO_GAUSS(data->asa[1]);
-	data->raw_to_gauss[2] = AK09911_RAW_TO_GAUSS(data->asa[2]);
-
-	return 0;
-}
-
-static int ak09911_verify_chip_id(struct i2c_client *client)
-{
-	u8 wia_val[2];
-	int ret;
-
-	ret = i2c_smbus_read_i2c_block_data(client, AK09911_REG_WIA1,
-					    2, wia_val);
-	if (ret < 0) {
-		dev_err(&client->dev, "Error reading WIA\n");
-		return ret;
-	}
-
-	dev_dbg(&client->dev, "WIA %02x %02x\n", wia_val[0], wia_val[1]);
-
-	if (wia_val[0] != AK09911_WIA1_VALUE ||
-		wia_val[1] != AK09911_WIA2_VALUE) {
-		dev_err(&client->dev, "Device ak09911 not found\n");
-		return -ENODEV;
-	}
-
-	return 0;
-}
-
-static int wait_conversion_complete_polled(struct ak09911_data *data)
-{
-	struct i2c_client *client = data->client;
-	u8 read_status;
-	u32 timeout_ms = AK09911_MAX_CONVERSION_TIMEOUT_MS;
-	int ret;
-
-	/* Wait for the conversion to complete. */
-	while (timeout_ms) {
-		msleep_interruptible(AK09911_CONVERSION_DONE_POLL_TIME_MS);
-		ret = i2c_smbus_read_byte_data(client, AK09911_REG_ST1);
-		if (ret < 0) {
-			dev_err(&client->dev, "Error in reading ST1\n");
-			return ret;
-		}
-		read_status = ret & 0x01;
-		if (read_status)
-			break;
-		timeout_ms -= AK09911_CONVERSION_DONE_POLL_TIME_MS;
-	}
-	if (!timeout_ms) {
-		dev_err(&client->dev, "Conversion timeout happened\n");
-		return -EIO;
-	}
-
-	return read_status;
-}
-
-static int ak09911_read_axis(struct iio_dev *indio_dev, int index, int *val)
-{
-	struct ak09911_data *data = iio_priv(indio_dev);
-	struct i2c_client *client = data->client;
-	int ret;
-
-	mutex_lock(&data->lock);
-
-	ret = ak09911_set_mode(client, AK09911_MODE_SNG_MEASURE);
-	if (ret < 0)
-		goto fn_exit;
-
-	ret = wait_conversion_complete_polled(data);
-	if (ret < 0)
-		goto fn_exit;
-
-	/* Read data */
-	ret = i2c_smbus_read_word_data(client, ak09911_index_to_reg[index]);
-	if (ret < 0) {
-		dev_err(&client->dev, "Read axis data fails\n");
-		goto fn_exit;
-	}
-
-	mutex_unlock(&data->lock);
-
-	/* Clamp to valid range. */
-	*val = sign_extend32(clamp_t(s16, ret, -8192, 8191), 13);
-
-	return IIO_VAL_INT;
-
-fn_exit:
-	mutex_unlock(&data->lock);
-
-	return ret;
-}
-
-static int ak09911_read_raw(struct iio_dev *indio_dev,
-			    struct iio_chan_spec const *chan,
-			    int *val, int *val2,
-			    long mask)
-{
-	struct ak09911_data *data = iio_priv(indio_dev);
-
-	switch (mask) {
-	case IIO_CHAN_INFO_RAW:
-		return ak09911_read_axis(indio_dev, chan->address, val);
-	case IIO_CHAN_INFO_SCALE:
-		*val = 0;
-		*val2 = data->raw_to_gauss[chan->address];
-		return IIO_VAL_INT_PLUS_MICRO;
-	}
-
-	return -EINVAL;
-}
-
-#define AK09911_CHANNEL(axis, index)					\
-	{								\
-		.type = IIO_MAGN,					\
-		.modified = 1,						\
-		.channel2 = IIO_MOD_##axis,				\
-		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |		\
-			     BIT(IIO_CHAN_INFO_SCALE),			\
-		.address = index,					\
-	}
-
-static const struct iio_chan_spec ak09911_channels[] = {
-	AK09911_CHANNEL(X, 0), AK09911_CHANNEL(Y, 1), AK09911_CHANNEL(Z, 2),
-};
-
-static const struct iio_info ak09911_info = {
-	.read_raw = &ak09911_read_raw,
-	.driver_module = THIS_MODULE,
-};
-
-static const struct acpi_device_id ak_acpi_match[] = {
-	{"AK009911", 0},
-	{ },
-};
-MODULE_DEVICE_TABLE(acpi, ak_acpi_match);
-
-static int ak09911_probe(struct i2c_client *client,
-			 const struct i2c_device_id *id)
-{
-	struct iio_dev *indio_dev;
-	struct ak09911_data *data;
-	const char *name;
-	int ret;
-
-	ret = ak09911_verify_chip_id(client);
-	if (ret) {
-		dev_err(&client->dev, "AK00911 not detected\n");
-		return -ENODEV;
-	}
-
-	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
-	if (indio_dev == NULL)
-		return -ENOMEM;
-
-	data = iio_priv(indio_dev);
-	i2c_set_clientdata(client, indio_dev);
-
-	data->client = client;
-	mutex_init(&data->lock);
-
-	ret = ak09911_get_asa(client);
-	if (ret)
-		return ret;
-
-	if (id)
-		name = id->name;
-	else if (ACPI_HANDLE(&client->dev))
-		name = dev_name(&client->dev);
-	else
-		return -ENODEV;
-
-	dev_dbg(&client->dev, "Asahi compass chip %s\n", name);
-
-	indio_dev->dev.parent = &client->dev;
-	indio_dev->channels = ak09911_channels;
-	indio_dev->num_channels = ARRAY_SIZE(ak09911_channels);
-	indio_dev->info = &ak09911_info;
-	indio_dev->modes = INDIO_DIRECT_MODE;
-	indio_dev->name = name;
-
-	return devm_iio_device_register(&client->dev, indio_dev);
-}
-
-static const struct i2c_device_id ak09911_id[] = {
-	{"ak09911", 0},
-	{}
-};
-
-MODULE_DEVICE_TABLE(i2c, ak09911_id);
-
-static struct i2c_driver ak09911_driver = {
-	.driver = {
-		.name	= "ak09911",
-		.acpi_match_table = ACPI_PTR(ak_acpi_match),
-	},
-	.probe		= ak09911_probe,
-	.id_table	= ak09911_id,
-};
-module_i2c_driver(ak09911_driver);
-
-MODULE_AUTHOR("Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>");
-MODULE_LICENSE("GPL v2");
-MODULE_DESCRIPTION("AK09911 Compass driver");
diff --git a/drivers/iio/magnetometer/ak8975.c b/drivers/iio/magnetometer/ak8975.c
index 58c9a78..55d4732 100644
--- a/drivers/iio/magnetometer/ak8975.c
+++ b/drivers/iio/magnetometer/ak8975.c
@@ -81,6 +81,58 @@
 #define AK8975_MAX_REGS			AK8975_REG_ASAZ
 
 /*
+ * AK09912 Register definitions
+ */
+#define AK09912_REG_WIA1		0x00
+#define AK09912_REG_WIA2		0x01
+#define AK09912_DEVICE_ID		0x04
+#define AK09911_DEVICE_ID		0x05
+
+#define AK09911_REG_INFO1		0x02
+#define AK09911_REG_INFO2		0x03
+
+#define AK09912_REG_ST1			0x10
+
+#define AK09912_REG_ST1_DRDY_SHIFT	0
+#define AK09912_REG_ST1_DRDY_MASK	(1 << AK09912_REG_ST1_DRDY_SHIFT)
+
+#define AK09912_REG_HXL			0x11
+#define AK09912_REG_HXH			0x12
+#define AK09912_REG_HYL			0x13
+#define AK09912_REG_HYH			0x14
+#define AK09912_REG_HZL			0x15
+#define AK09912_REG_HZH			0x16
+#define AK09912_REG_TMPS		0x17
+
+#define AK09912_REG_ST2			0x18
+#define AK09912_REG_ST2_HOFL_SHIFT	3
+#define AK09912_REG_ST2_HOFL_MASK	(1 << AK09912_REG_ST2_HOFL_SHIFT)
+
+#define AK09912_REG_CNTL1		0x30
+
+#define AK09912_REG_CNTL2		0x31
+#define AK09912_REG_CNTL_MODE_POWER_DOWN	0x00
+#define AK09912_REG_CNTL_MODE_ONCE	0x01
+#define AK09912_REG_CNTL_MODE_SELF_TEST	0x10
+#define AK09912_REG_CNTL_MODE_FUSE_ROM	0x1F
+#define AK09912_REG_CNTL2_MODE_SHIFT	0
+#define AK09912_REG_CNTL2_MODE_MASK	(0x1F << AK09912_REG_CNTL2_MODE_SHIFT)
+
+#define AK09912_REG_CNTL3		0x32
+
+#define AK09912_REG_TS1			0x33
+#define AK09912_REG_TS2			0x34
+#define AK09912_REG_TS3			0x35
+#define AK09912_REG_I2CDIS		0x36
+#define AK09912_REG_TS4			0x37
+
+#define AK09912_REG_ASAX		0x60
+#define AK09912_REG_ASAY		0x61
+#define AK09912_REG_ASAZ		0x62
+
+#define AK09912_MAX_REGS		AK09912_REG_ASAZ
+
+/*
  * Miscellaneous values.
  */
 #define AK8975_MAX_CONVERSION_TIMEOUT	500
@@ -130,22 +182,37 @@ long ak8975_raw_to_gauss(u16 data)
 }
 
 /*
- * For AK8963, same calculation, but the device is less sensitive:
+ * For AK8963 and AK09911, same calculation, but the device is less sensitive:
  *
  * H is in the range of +-8190.  The magnetometer has a range of
  * +-4912uT.  To go from the raw value to uT is:
  *
  * HuT = H * 4912/8190, or roughly, 6/10, instead of 3/10.
  */
-long ak8963_raw_to_gauss(u16 data)
+long ak8963_09911_raw_to_gauss(u16 data)
 {
 	return (((long)data + 128) * 6000) / 256;
 }
 
+/*
+ * For AK09912, same calculation, except the device is more sensitive:
+ *
+ * H is in the range of -32752 to 32752.  The magnetometer has a range of
+ * +-4912uT.  To go from the raw value to uT is:
+ *
+ * HuT = H * 4912/32752, or roughly, 3/20, instead of 3/10.
+ */
+long ak09912_raw_to_gauss(u16 data)
+{
+	return (((long)data + 128) * 1500) / 256;
+}
+
 /* Compatible Asahi Kasei Compass parts */
 enum asahi_compass_chipset {
 	AK8975,
 	AK8963,
+	AK09911,
+	AK09912,
 	AK_MAX_TYPE
 };
 
@@ -210,7 +277,7 @@ struct ak_def {
 	},
 	{
 		.type = AK8963,
-		.raw_to_gauss = ak8963_raw_to_gauss,
+		.raw_to_gauss = ak8963_09911_raw_to_gauss,
 		.range = 8190,
 		.ctrl_regs = {
 			AK8975_REG_ST1,
@@ -233,6 +300,56 @@ struct ak_def {
 			AK8975_REG_HYL,
 			AK8975_REG_HZL},
 	},
+	{
+		.type = AK09911,
+		.raw_to_gauss = ak8963_09911_raw_to_gauss,
+		.range = 8192,
+		.ctrl_regs = {
+			AK09912_REG_ST1,
+			AK09912_REG_ST2,
+			AK09912_REG_CNTL2,
+			AK09912_REG_ASAX,
+			AK09912_MAX_REGS},
+		.ctrl_masks = {
+			AK09912_REG_ST1_DRDY_MASK,
+			AK09912_REG_ST2_HOFL_MASK,
+			0,
+			AK09912_REG_CNTL2_MODE_MASK},
+		.ctrl_modes = {
+			AK09912_REG_CNTL_MODE_POWER_DOWN,
+			AK09912_REG_CNTL_MODE_ONCE,
+			AK09912_REG_CNTL_MODE_SELF_TEST,
+			AK09912_REG_CNTL_MODE_FUSE_ROM},
+		.data_regs = {
+			AK09912_REG_HXL,
+			AK09912_REG_HYL,
+			AK09912_REG_HZL},
+	},
+	{
+		.type = AK09912,
+		.raw_to_gauss = ak09912_raw_to_gauss,
+		.range = 32752,
+		.ctrl_regs = {
+			AK09912_REG_ST1,
+			AK09912_REG_ST2,
+			AK09912_REG_CNTL2,
+			AK09912_REG_ASAX,
+			AK09912_MAX_REGS},
+		.ctrl_masks = {
+			AK09912_REG_ST1_DRDY_MASK,
+			AK09912_REG_ST2_HOFL_MASK,
+			0,
+			AK09912_REG_CNTL2_MODE_MASK},
+		.ctrl_modes = {
+			AK09912_REG_CNTL_MODE_POWER_DOWN,
+			AK09912_REG_CNTL_MODE_ONCE,
+			AK09912_REG_CNTL_MODE_SELF_TEST,
+			AK09912_REG_CNTL_MODE_FUSE_ROM},
+		.data_regs = {
+			AK09912_REG_HXL,
+			AK09912_REG_HYL,
+			AK09912_REG_HZL},
+	}
 };
 
 /*
@@ -253,6 +370,52 @@ struct ak8975_data {
 };
 
 /*
+ * Return 0 if the i2c device is the one we expect.
+ * return a negative error number otherwise
+ */
+static int ak8975_who_i_am(struct i2c_client *client,
+			   enum asahi_compass_chipset type)
+{
+	u8 wia_val[2];
+	int ret;
+
+	/*
+	 * Signature for each device:
+	 * Device   |  WIA1      |  WIA2
+	 * AK09912  |  DEVICE_ID |  AK09912_DEVICE_ID
+	 * AK09911  |  DEVICE_ID |  AK09911_DEVICE_ID
+	 * AK8975   |  DEVICE_ID |  NA
+	 * AK8963   |  DEVICE_ID |  NA
+	 */
+	ret = i2c_smbus_read_i2c_block_data(client, AK09912_REG_WIA1,
+					    2, wia_val);
+	if (ret < 0) {
+		dev_err(&client->dev, "Error reading WIA\n");
+		return ret;
+	}
+
+	if (wia_val[0] != AK8975_DEVICE_ID)
+		return -ENODEV;
+
+	switch (type) {
+	case AK8975:
+	case AK8963:
+		return 0;
+	case AK09911:
+		if (wia_val[1] == AK09911_DEVICE_ID)
+			return 0;
+		break;
+	case AK09912:
+		if (wia_val[1] == AK09912_DEVICE_ID)
+			return 0;
+		break;
+	default:
+		dev_err(&client->dev, "Type %d unknown\n", type);
+	}
+	return -ENODEV;
+}
+
+/*
  * Helper function to write to CNTL register.
  */
 static int ak8975_set_mode(struct ak8975_data *data, enum ak_ctrl_mode mode)
@@ -327,21 +490,8 @@ static int ak8975_setup(struct i2c_client *client)
 {
 	struct iio_dev *indio_dev = i2c_get_clientdata(client);
 	struct ak8975_data *data = iio_priv(indio_dev);
-	u8 device_id;
 	int ret;
 
-	/* Confirm that the device we're talking to is really an AK8975. */
-	ret = i2c_smbus_read_byte_data(client, AK8975_REG_WIA);
-	if (ret < 0) {
-		dev_err(&client->dev, "Error reading WIA\n");
-		return ret;
-	}
-	device_id = ret;
-	if (device_id != AK8975_DEVICE_ID) {
-		dev_err(&client->dev, "Device ak8975 not found\n");
-		return -ENODEV;
-	}
-
 	/* Write the fused rom access mode. */
 	ret = ak8975_set_mode(data, FUSE_ROM);
 	if (ret < 0) {
@@ -552,6 +702,8 @@ static const struct acpi_device_id ak_acpi_match[] = {
 	{"AK8975", AK8975},
 	{"AK8963", AK8963},
 	{"INVN6500", AK8963},
+	{"AK09911", AK09911},
+	{"AK09912", AK09912},
 	{ },
 };
 MODULE_DEVICE_TABLE(acpi, ak_acpi_match);
@@ -631,6 +783,11 @@ static int ak8975_probe(struct i2c_client *client,
 	}
 
 	data->def = &ak_def_array[chipset];
+	err = ak8975_who_i_am(client, data->def->type);
+	if (err < 0) {
+		dev_err(&client->dev, "Unexpected device\n");
+		return err;
+	}
 	dev_dbg(&client->dev, "Asahi compass chip %s\n", name);
 
 	/* Perform some basic start-of-day setup of the device. */
@@ -653,6 +810,8 @@ static int ak8975_probe(struct i2c_client *client,
 static const struct i2c_device_id ak8975_id[] = {
 	{"ak8975", AK8975},
 	{"ak8963", AK8963},
+	{"ak09911", AK09911},
+	{"ak09912", AK09912},
 	{}
 };
 
@@ -663,6 +822,10 @@ static const struct of_device_id ak8975_of_match[] = {
 	{ .compatible = "ak8975", },
 	{ .compatible = "asahi-kasei,ak8963", },
 	{ .compatible = "ak8963", },
+	{ .compatible = "asahi-kasei,ak09911", },
+	{ .compatible = "ak09911", },
+	{ .compatible = "asahi-kasei,ak09912", },
+	{ .compatible = "ak09912", },
 	{}
 };
 MODULE_DEVICE_TABLE(of, ak8975_of_match);
-- 
2.1.0.rc2.206.gedb03e5

Re: [PATCH v4 3/3] iio: ak8975: add ak09911 and ak09912 support

[Jonathan Cameron]

On 21/11/14 18:45, Gwendal Grignou wrote:
> Add 2 new definition entries to support ak0991x compass.
> Add a more advanced function to check we are dealing with the
> expected device.
> Remove standalone driver for ak09911.
> 
> Tested-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
> Signed-off-by: Gwendal Grignou <gwendal@chromium.org>
Convention puts the author sign off first

reviewed-by, tested-by, acked-by, sign-offs of people along the chain afterwards
and whoever applied the patches sign off last.

Anyhow, reordered and applied to the togreg branch of iio.git -
initially pushed out as testing for the autobuilders to play with it.

Thanks

Jonathan
> ---
>  drivers/iio/magnetometer/Kconfig   |  15 +-
>  drivers/iio/magnetometer/Makefile  |   1 -
>  drivers/iio/magnetometer/ak09911.c | 326 -------------------------------------
>  drivers/iio/magnetometer/ak8975.c  | 195 ++++++++++++++++++++--
>  4 files changed, 184 insertions(+), 353 deletions(-)
>  delete mode 100644 drivers/iio/magnetometer/ak09911.c
> 
> diff --git a/drivers/iio/magnetometer/Kconfig b/drivers/iio/magnetometer/Kconfig
> index b2dba9e..4c7a4c5 100644
> --- a/drivers/iio/magnetometer/Kconfig
> +++ b/drivers/iio/magnetometer/Kconfig
> @@ -6,26 +6,21 @@
>  menu "Magnetometer sensors"
>  
>  config AK8975
> -	tristate "Asahi Kasei AK8975 3-Axis Magnetometer"
> +	tristate "Asahi Kasei AK 3-Axis Magnetometer"
>  	depends on I2C
>  	depends on GPIOLIB
>  	help
> -	  Say yes here to build support for Asahi Kasei AK8975 3-Axis
> -	  Magnetometer. This driver can also support AK8963, if i2c
> -	  device name is identified as ak8963.
> +	  Say yes here to build support for Asahi Kasei AK8975, AK8963,
> +	  AK09911 or AK09912 3-Axis Magnetometer.
>  
>  	  To compile this driver as a module, choose M here: the module
>  	  will be called ak8975.
>  
>  config AK09911
>  	tristate "Asahi Kasei AK09911 3-axis Compass"
> -	depends on I2C
> +	select AK8975
>  	help
> -	  Say yes here to build support for Asahi Kasei AK09911 3-Axis
> -	  Magnetometer.
> -
> -	  To compile this driver as a module, choose M here: the module
> -	  will be called ak09911.
> +	  Deprecated: AK09911 is now supported by AK8975 driver.
>  
>  config MAG3110
>  	tristate "Freescale MAG3110 3-Axis Magnetometer"
> diff --git a/drivers/iio/magnetometer/Makefile b/drivers/iio/magnetometer/Makefile
> index b91315e..0f5d3c9 100644
> --- a/drivers/iio/magnetometer/Makefile
> +++ b/drivers/iio/magnetometer/Makefile
> @@ -3,7 +3,6 @@
>  #
>  
>  # When adding new entries keep the list in alphabetical order
> -obj-$(CONFIG_AK09911)	+= ak09911.o
>  obj-$(CONFIG_AK8975)	+= ak8975.o
>  obj-$(CONFIG_MAG3110)	+= mag3110.o
>  obj-$(CONFIG_HID_SENSOR_MAGNETOMETER_3D) += hid-sensor-magn-3d.o
> diff --git a/drivers/iio/magnetometer/ak09911.c b/drivers/iio/magnetometer/ak09911.c
> deleted file mode 100644
> index b2bc942..0000000
> --- a/drivers/iio/magnetometer/ak09911.c
> +++ /dev/null
> @@ -1,326 +0,0 @@
> -/*
> - * AK09911 3-axis compass driver
> - * Copyright (c) 2014, Intel Corporation.
> - *
> - * This program is free software; you can redistribute it and/or modify it
> - * under the terms and conditions of the GNU General Public License,
> - * version 2, as published by the Free Software Foundation.
> - *
> - * This program is distributed in the hope it will be useful, but WITHOUT
> - * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
> - * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
> - * more details.
> - */
> -
> -#include <linux/kernel.h>
> -#include <linux/module.h>
> -#include <linux/init.h>
> -#include <linux/types.h>
> -#include <linux/slab.h>
> -#include <linux/delay.h>
> -#include <linux/i2c.h>
> -#include <linux/acpi.h>
> -#include <linux/iio/iio.h>
> -
> -#define AK09911_REG_WIA1		0x00
> -#define AK09911_REG_WIA2		0x01
> -#define AK09911_WIA1_VALUE		0x48
> -#define AK09911_WIA2_VALUE		0x05
> -
> -#define AK09911_REG_ST1			0x10
> -#define AK09911_REG_HXL			0x11
> -#define AK09911_REG_HXH			0x12
> -#define AK09911_REG_HYL			0x13
> -#define AK09911_REG_HYH			0x14
> -#define AK09911_REG_HZL			0x15
> -#define AK09911_REG_HZH			0x16
> -
> -#define AK09911_REG_ASAX		0x60
> -#define AK09911_REG_ASAY		0x61
> -#define AK09911_REG_ASAZ		0x62
> -
> -#define AK09911_REG_CNTL1		0x30
> -#define AK09911_REG_CNTL2		0x31
> -#define AK09911_REG_CNTL3		0x32
> -
> -#define AK09911_MODE_SNG_MEASURE	0x01
> -#define AK09911_MODE_SELF_TEST		0x10
> -#define AK09911_MODE_FUSE_ACCESS	0x1F
> -#define AK09911_MODE_POWERDOWN		0x00
> -#define AK09911_RESET_DATA		0x01
> -
> -#define AK09911_REG_CNTL1		0x30
> -#define AK09911_REG_CNTL2		0x31
> -#define AK09911_REG_CNTL3		0x32
> -
> -#define AK09911_RAW_TO_GAUSS(asa)	((((asa) + 128) * 6000) / 256)
> -
> -#define AK09911_MAX_CONVERSION_TIMEOUT_MS	500
> -#define AK09911_CONVERSION_DONE_POLL_TIME_MS	10
> -
> -struct ak09911_data {
> -	struct i2c_client	*client;
> -	struct mutex		lock;
> -	u8			asa[3];
> -	long			raw_to_gauss[3];
> -};
> -
> -static const int ak09911_index_to_reg[] = {
> -	AK09911_REG_HXL, AK09911_REG_HYL, AK09911_REG_HZL,
> -};
> -
> -static int ak09911_set_mode(struct i2c_client *client, u8 mode)
> -{
> -	int ret;
> -
> -	switch (mode) {
> -	case AK09911_MODE_SNG_MEASURE:
> -	case AK09911_MODE_SELF_TEST:
> -	case AK09911_MODE_FUSE_ACCESS:
> -	case AK09911_MODE_POWERDOWN:
> -		ret = i2c_smbus_write_byte_data(client,
> -						AK09911_REG_CNTL2, mode);
> -		if (ret < 0) {
> -			dev_err(&client->dev, "set_mode error\n");
> -			return ret;
> -		}
> -		/* After mode change wait atleast 100us */
> -		usleep_range(100, 500);
> -		break;
> -	default:
> -		dev_err(&client->dev,
> -			"%s: Unknown mode(%d).", __func__, mode);
> -		return -EINVAL;
> -	}
> -
> -	return ret;
> -}
> -
> -/* Get Sensitivity Adjustment value */
> -static int ak09911_get_asa(struct i2c_client *client)
> -{
> -	struct iio_dev *indio_dev = i2c_get_clientdata(client);
> -	struct ak09911_data *data = iio_priv(indio_dev);
> -	int ret;
> -
> -	ret = ak09911_set_mode(client, AK09911_MODE_FUSE_ACCESS);
> -	if (ret < 0)
> -		return ret;
> -
> -	/* Get asa data and store in the device data. */
> -	ret = i2c_smbus_read_i2c_block_data(client, AK09911_REG_ASAX,
> -					    3, data->asa);
> -	if (ret < 0) {
> -		dev_err(&client->dev, "Not able to read asa data\n");
> -		return ret;
> -	}
> -
> -	ret = ak09911_set_mode(client,  AK09911_MODE_POWERDOWN);
> -	if (ret < 0)
> -		return ret;
> -
> -	data->raw_to_gauss[0] = AK09911_RAW_TO_GAUSS(data->asa[0]);
> -	data->raw_to_gauss[1] = AK09911_RAW_TO_GAUSS(data->asa[1]);
> -	data->raw_to_gauss[2] = AK09911_RAW_TO_GAUSS(data->asa[2]);
> -
> -	return 0;
> -}
> -
> -static int ak09911_verify_chip_id(struct i2c_client *client)
> -{
> -	u8 wia_val[2];
> -	int ret;
> -
> -	ret = i2c_smbus_read_i2c_block_data(client, AK09911_REG_WIA1,
> -					    2, wia_val);
> -	if (ret < 0) {
> -		dev_err(&client->dev, "Error reading WIA\n");
> -		return ret;
> -	}
> -
> -	dev_dbg(&client->dev, "WIA %02x %02x\n", wia_val[0], wia_val[1]);
> -
> -	if (wia_val[0] != AK09911_WIA1_VALUE ||
> -		wia_val[1] != AK09911_WIA2_VALUE) {
> -		dev_err(&client->dev, "Device ak09911 not found\n");
> -		return -ENODEV;
> -	}
> -
> -	return 0;
> -}
> -
> -static int wait_conversion_complete_polled(struct ak09911_data *data)
> -{
> -	struct i2c_client *client = data->client;
> -	u8 read_status;
> -	u32 timeout_ms = AK09911_MAX_CONVERSION_TIMEOUT_MS;
> -	int ret;
> -
> -	/* Wait for the conversion to complete. */
> -	while (timeout_ms) {
> -		msleep_interruptible(AK09911_CONVERSION_DONE_POLL_TIME_MS);
> -		ret = i2c_smbus_read_byte_data(client, AK09911_REG_ST1);
> -		if (ret < 0) {
> -			dev_err(&client->dev, "Error in reading ST1\n");
> -			return ret;
> -		}
> -		read_status = ret & 0x01;
> -		if (read_status)
> -			break;
> -		timeout_ms -= AK09911_CONVERSION_DONE_POLL_TIME_MS;
> -	}
> -	if (!timeout_ms) {
> -		dev_err(&client->dev, "Conversion timeout happened\n");
> -		return -EIO;
> -	}
> -
> -	return read_status;
> -}
> -
> -static int ak09911_read_axis(struct iio_dev *indio_dev, int index, int *val)
> -{
> -	struct ak09911_data *data = iio_priv(indio_dev);
> -	struct i2c_client *client = data->client;
> -	int ret;
> -
> -	mutex_lock(&data->lock);
> -
> -	ret = ak09911_set_mode(client, AK09911_MODE_SNG_MEASURE);
> -	if (ret < 0)
> -		goto fn_exit;
> -
> -	ret = wait_conversion_complete_polled(data);
> -	if (ret < 0)
> -		goto fn_exit;
> -
> -	/* Read data */
> -	ret = i2c_smbus_read_word_data(client, ak09911_index_to_reg[index]);
> -	if (ret < 0) {
> -		dev_err(&client->dev, "Read axis data fails\n");
> -		goto fn_exit;
> -	}
> -
> -	mutex_unlock(&data->lock);
> -
> -	/* Clamp to valid range. */
> -	*val = sign_extend32(clamp_t(s16, ret, -8192, 8191), 13);
> -
> -	return IIO_VAL_INT;
> -
> -fn_exit:
> -	mutex_unlock(&data->lock);
> -
> -	return ret;
> -}
> -
> -static int ak09911_read_raw(struct iio_dev *indio_dev,
> -			    struct iio_chan_spec const *chan,
> -			    int *val, int *val2,
> -			    long mask)
> -{
> -	struct ak09911_data *data = iio_priv(indio_dev);
> -
> -	switch (mask) {
> -	case IIO_CHAN_INFO_RAW:
> -		return ak09911_read_axis(indio_dev, chan->address, val);
> -	case IIO_CHAN_INFO_SCALE:
> -		*val = 0;
> -		*val2 = data->raw_to_gauss[chan->address];
> -		return IIO_VAL_INT_PLUS_MICRO;
> -	}
> -
> -	return -EINVAL;
> -}
> -
> -#define AK09911_CHANNEL(axis, index)					\
> -	{								\
> -		.type = IIO_MAGN,					\
> -		.modified = 1,						\
> -		.channel2 = IIO_MOD_##axis,				\
> -		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |		\
> -			     BIT(IIO_CHAN_INFO_SCALE),			\
> -		.address = index,					\
> -	}
> -
> -static const struct iio_chan_spec ak09911_channels[] = {
> -	AK09911_CHANNEL(X, 0), AK09911_CHANNEL(Y, 1), AK09911_CHANNEL(Z, 2),
> -};
> -
> -static const struct iio_info ak09911_info = {
> -	.read_raw = &ak09911_read_raw,
> -	.driver_module = THIS_MODULE,
> -};
> -
> -static const struct acpi_device_id ak_acpi_match[] = {
> -	{"AK009911", 0},
> -	{ },
> -};
> -MODULE_DEVICE_TABLE(acpi, ak_acpi_match);
> -
> -static int ak09911_probe(struct i2c_client *client,
> -			 const struct i2c_device_id *id)
> -{
> -	struct iio_dev *indio_dev;
> -	struct ak09911_data *data;
> -	const char *name;
> -	int ret;
> -
> -	ret = ak09911_verify_chip_id(client);
> -	if (ret) {
> -		dev_err(&client->dev, "AK00911 not detected\n");
> -		return -ENODEV;
> -	}
> -
> -	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
> -	if (indio_dev == NULL)
> -		return -ENOMEM;
> -
> -	data = iio_priv(indio_dev);
> -	i2c_set_clientdata(client, indio_dev);
> -
> -	data->client = client;
> -	mutex_init(&data->lock);
> -
> -	ret = ak09911_get_asa(client);
> -	if (ret)
> -		return ret;
> -
> -	if (id)
> -		name = id->name;
> -	else if (ACPI_HANDLE(&client->dev))
> -		name = dev_name(&client->dev);
> -	else
> -		return -ENODEV;
> -
> -	dev_dbg(&client->dev, "Asahi compass chip %s\n", name);
> -
> -	indio_dev->dev.parent = &client->dev;
> -	indio_dev->channels = ak09911_channels;
> -	indio_dev->num_channels = ARRAY_SIZE(ak09911_channels);
> -	indio_dev->info = &ak09911_info;
> -	indio_dev->modes = INDIO_DIRECT_MODE;
> -	indio_dev->name = name;
> -
> -	return devm_iio_device_register(&client->dev, indio_dev);
> -}
> -
> -static const struct i2c_device_id ak09911_id[] = {
> -	{"ak09911", 0},
> -	{}
> -};
> -
> -MODULE_DEVICE_TABLE(i2c, ak09911_id);
> -
> -static struct i2c_driver ak09911_driver = {
> -	.driver = {
> -		.name	= "ak09911",
> -		.acpi_match_table = ACPI_PTR(ak_acpi_match),
> -	},
> -	.probe		= ak09911_probe,
> -	.id_table	= ak09911_id,
> -};
> -module_i2c_driver(ak09911_driver);
> -
> -MODULE_AUTHOR("Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>");
> -MODULE_LICENSE("GPL v2");
> -MODULE_DESCRIPTION("AK09911 Compass driver");
> diff --git a/drivers/iio/magnetometer/ak8975.c b/drivers/iio/magnetometer/ak8975.c
> index 58c9a78..55d4732 100644
> --- a/drivers/iio/magnetometer/ak8975.c
> +++ b/drivers/iio/magnetometer/ak8975.c
> @@ -81,6 +81,58 @@
>  #define AK8975_MAX_REGS			AK8975_REG_ASAZ
>  
>  /*
> + * AK09912 Register definitions
> + */
> +#define AK09912_REG_WIA1		0x00
> +#define AK09912_REG_WIA2		0x01
> +#define AK09912_DEVICE_ID		0x04
> +#define AK09911_DEVICE_ID		0x05
> +
> +#define AK09911_REG_INFO1		0x02
> +#define AK09911_REG_INFO2		0x03
> +
> +#define AK09912_REG_ST1			0x10
> +
> +#define AK09912_REG_ST1_DRDY_SHIFT	0
> +#define AK09912_REG_ST1_DRDY_MASK	(1 << AK09912_REG_ST1_DRDY_SHIFT)
> +
> +#define AK09912_REG_HXL			0x11
> +#define AK09912_REG_HXH			0x12
> +#define AK09912_REG_HYL			0x13
> +#define AK09912_REG_HYH			0x14
> +#define AK09912_REG_HZL			0x15
> +#define AK09912_REG_HZH			0x16
> +#define AK09912_REG_TMPS		0x17
> +
> +#define AK09912_REG_ST2			0x18
> +#define AK09912_REG_ST2_HOFL_SHIFT	3
> +#define AK09912_REG_ST2_HOFL_MASK	(1 << AK09912_REG_ST2_HOFL_SHIFT)
> +
> +#define AK09912_REG_CNTL1		0x30
> +
> +#define AK09912_REG_CNTL2		0x31
> +#define AK09912_REG_CNTL_MODE_POWER_DOWN	0x00
> +#define AK09912_REG_CNTL_MODE_ONCE	0x01
> +#define AK09912_REG_CNTL_MODE_SELF_TEST	0x10
> +#define AK09912_REG_CNTL_MODE_FUSE_ROM	0x1F
> +#define AK09912_REG_CNTL2_MODE_SHIFT	0
> +#define AK09912_REG_CNTL2_MODE_MASK	(0x1F << AK09912_REG_CNTL2_MODE_SHIFT)
> +
> +#define AK09912_REG_CNTL3		0x32
> +
> +#define AK09912_REG_TS1			0x33
> +#define AK09912_REG_TS2			0x34
> +#define AK09912_REG_TS3			0x35
> +#define AK09912_REG_I2CDIS		0x36
> +#define AK09912_REG_TS4			0x37
> +
> +#define AK09912_REG_ASAX		0x60
> +#define AK09912_REG_ASAY		0x61
> +#define AK09912_REG_ASAZ		0x62
> +
> +#define AK09912_MAX_REGS		AK09912_REG_ASAZ
> +
> +/*
>   * Miscellaneous values.
>   */
>  #define AK8975_MAX_CONVERSION_TIMEOUT	500
> @@ -130,22 +182,37 @@ long ak8975_raw_to_gauss(u16 data)
>  }
>  
>  /*
> - * For AK8963, same calculation, but the device is less sensitive:
> + * For AK8963 and AK09911, same calculation, but the device is less sensitive:
>   *
>   * H is in the range of +-8190.  The magnetometer has a range of
>   * +-4912uT.  To go from the raw value to uT is:
>   *
>   * HuT = H * 4912/8190, or roughly, 6/10, instead of 3/10.
>   */
> -long ak8963_raw_to_gauss(u16 data)
> +long ak8963_09911_raw_to_gauss(u16 data)
>  {
>  	return (((long)data + 128) * 6000) / 256;
>  }
>  
> +/*
> + * For AK09912, same calculation, except the device is more sensitive:
> + *
> + * H is in the range of -32752 to 32752.  The magnetometer has a range of
> + * +-4912uT.  To go from the raw value to uT is:
> + *
> + * HuT = H * 4912/32752, or roughly, 3/20, instead of 3/10.
> + */
> +long ak09912_raw_to_gauss(u16 data)
> +{
> +	return (((long)data + 128) * 1500) / 256;
> +}
> +
>  /* Compatible Asahi Kasei Compass parts */
>  enum asahi_compass_chipset {
>  	AK8975,
>  	AK8963,
> +	AK09911,
> +	AK09912,
>  	AK_MAX_TYPE
>  };
>  
> @@ -210,7 +277,7 @@ struct ak_def {
>  	},
>  	{
>  		.type = AK8963,
> -		.raw_to_gauss = ak8963_raw_to_gauss,
> +		.raw_to_gauss = ak8963_09911_raw_to_gauss,
>  		.range = 8190,
>  		.ctrl_regs = {
>  			AK8975_REG_ST1,
> @@ -233,6 +300,56 @@ struct ak_def {
>  			AK8975_REG_HYL,
>  			AK8975_REG_HZL},
>  	},
> +	{
> +		.type = AK09911,
> +		.raw_to_gauss = ak8963_09911_raw_to_gauss,
> +		.range = 8192,
> +		.ctrl_regs = {
> +			AK09912_REG_ST1,
> +			AK09912_REG_ST2,
> +			AK09912_REG_CNTL2,
> +			AK09912_REG_ASAX,
> +			AK09912_MAX_REGS},
> +		.ctrl_masks = {
> +			AK09912_REG_ST1_DRDY_MASK,
> +			AK09912_REG_ST2_HOFL_MASK,
> +			0,
> +			AK09912_REG_CNTL2_MODE_MASK},
> +		.ctrl_modes = {
> +			AK09912_REG_CNTL_MODE_POWER_DOWN,
> +			AK09912_REG_CNTL_MODE_ONCE,
> +			AK09912_REG_CNTL_MODE_SELF_TEST,
> +			AK09912_REG_CNTL_MODE_FUSE_ROM},
> +		.data_regs = {
> +			AK09912_REG_HXL,
> +			AK09912_REG_HYL,
> +			AK09912_REG_HZL},
> +	},
> +	{
> +		.type = AK09912,
> +		.raw_to_gauss = ak09912_raw_to_gauss,
> +		.range = 32752,
> +		.ctrl_regs = {
> +			AK09912_REG_ST1,
> +			AK09912_REG_ST2,
> +			AK09912_REG_CNTL2,
> +			AK09912_REG_ASAX,
> +			AK09912_MAX_REGS},
> +		.ctrl_masks = {
> +			AK09912_REG_ST1_DRDY_MASK,
> +			AK09912_REG_ST2_HOFL_MASK,
> +			0,
> +			AK09912_REG_CNTL2_MODE_MASK},
> +		.ctrl_modes = {
> +			AK09912_REG_CNTL_MODE_POWER_DOWN,
> +			AK09912_REG_CNTL_MODE_ONCE,
> +			AK09912_REG_CNTL_MODE_SELF_TEST,
> +			AK09912_REG_CNTL_MODE_FUSE_ROM},
> +		.data_regs = {
> +			AK09912_REG_HXL,
> +			AK09912_REG_HYL,
> +			AK09912_REG_HZL},
> +	}
>  };
>  
>  /*
> @@ -253,6 +370,52 @@ struct ak8975_data {
>  };
>  
>  /*
> + * Return 0 if the i2c device is the one we expect.
> + * return a negative error number otherwise
> + */
> +static int ak8975_who_i_am(struct i2c_client *client,
> +			   enum asahi_compass_chipset type)
> +{
> +	u8 wia_val[2];
> +	int ret;
> +
> +	/*
> +	 * Signature for each device:
> +	 * Device   |  WIA1      |  WIA2
> +	 * AK09912  |  DEVICE_ID |  AK09912_DEVICE_ID
> +	 * AK09911  |  DEVICE_ID |  AK09911_DEVICE_ID
> +	 * AK8975   |  DEVICE_ID |  NA
> +	 * AK8963   |  DEVICE_ID |  NA
> +	 */
> +	ret = i2c_smbus_read_i2c_block_data(client, AK09912_REG_WIA1,
> +					    2, wia_val);
> +	if (ret < 0) {
> +		dev_err(&client->dev, "Error reading WIA\n");
> +		return ret;
> +	}
> +
> +	if (wia_val[0] != AK8975_DEVICE_ID)
> +		return -ENODEV;
> +
> +	switch (type) {
> +	case AK8975:
> +	case AK8963:
> +		return 0;
> +	case AK09911:
> +		if (wia_val[1] == AK09911_DEVICE_ID)
> +			return 0;
> +		break;
> +	case AK09912:
> +		if (wia_val[1] == AK09912_DEVICE_ID)
> +			return 0;
> +		break;
> +	default:
> +		dev_err(&client->dev, "Type %d unknown\n", type);
> +	}
> +	return -ENODEV;
> +}
> +
> +/*
>   * Helper function to write to CNTL register.
>   */
>  static int ak8975_set_mode(struct ak8975_data *data, enum ak_ctrl_mode mode)
> @@ -327,21 +490,8 @@ static int ak8975_setup(struct i2c_client *client)
>  {
>  	struct iio_dev *indio_dev = i2c_get_clientdata(client);
>  	struct ak8975_data *data = iio_priv(indio_dev);
> -	u8 device_id;
>  	int ret;
>  
> -	/* Confirm that the device we're talking to is really an AK8975. */
> -	ret = i2c_smbus_read_byte_data(client, AK8975_REG_WIA);
> -	if (ret < 0) {
> -		dev_err(&client->dev, "Error reading WIA\n");
> -		return ret;
> -	}
> -	device_id = ret;
> -	if (device_id != AK8975_DEVICE_ID) {
> -		dev_err(&client->dev, "Device ak8975 not found\n");
> -		return -ENODEV;
> -	}
> -
>  	/* Write the fused rom access mode. */
>  	ret = ak8975_set_mode(data, FUSE_ROM);
>  	if (ret < 0) {
> @@ -552,6 +702,8 @@ static const struct acpi_device_id ak_acpi_match[] = {
>  	{"AK8975", AK8975},
>  	{"AK8963", AK8963},
>  	{"INVN6500", AK8963},
> +	{"AK09911", AK09911},
> +	{"AK09912", AK09912},
>  	{ },
>  };
>  MODULE_DEVICE_TABLE(acpi, ak_acpi_match);
> @@ -631,6 +783,11 @@ static int ak8975_probe(struct i2c_client *client,
>  	}
>  
>  	data->def = &ak_def_array[chipset];
> +	err = ak8975_who_i_am(client, data->def->type);
> +	if (err < 0) {
> +		dev_err(&client->dev, "Unexpected device\n");
> +		return err;
> +	}
>  	dev_dbg(&client->dev, "Asahi compass chip %s\n", name);
>  
>  	/* Perform some basic start-of-day setup of the device. */
> @@ -653,6 +810,8 @@ static int ak8975_probe(struct i2c_client *client,
>  static const struct i2c_device_id ak8975_id[] = {
>  	{"ak8975", AK8975},
>  	{"ak8963", AK8963},
> +	{"ak09911", AK09911},
> +	{"ak09912", AK09912},
>  	{}
>  };
>  
> @@ -663,6 +822,10 @@ static const struct of_device_id ak8975_of_match[] = {
>  	{ .compatible = "ak8975", },
>  	{ .compatible = "asahi-kasei,ak8963", },
>  	{ .compatible = "ak8963", },
> +	{ .compatible = "asahi-kasei,ak09911", },
> +	{ .compatible = "ak09911", },
> +	{ .compatible = "asahi-kasei,ak09912", },
> +	{ .compatible = "ak09912", },
>  	{}
>  };
>  MODULE_DEVICE_TABLE(of, ak8975_of_match);
> 

[PATCH v4 3/3] iio: ak8975: add ak09911 and ak09912 support

[Gwendal Grignou]

Add 2 new definition entries to support ak0991x compass.
Add a more advanced function to check we are dealing with the
expected device.
Remove standalone driver for ak09911.

Signed-off-by: Gwendal Grignou <gwendal@chromium.org>
Tested-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
---
 added static as requested by kbuild test robot.

 drivers/iio/magnetometer/Kconfig   |  15 +-
 drivers/iio/magnetometer/Makefile  |   1 -
 drivers/iio/magnetometer/ak09911.c | 326 -------------------------------------
 drivers/iio/magnetometer/ak8975.c  | 195 ++++++++++++++++++++--
 4 files changed, 184 insertions(+), 353 deletions(-)
 delete mode 100644 drivers/iio/magnetometer/ak09911.c

diff --git a/drivers/iio/magnetometer/Kconfig b/drivers/iio/magnetometer/Kconfig
index b2dba9e..4c7a4c5 100644
--- a/drivers/iio/magnetometer/Kconfig
+++ b/drivers/iio/magnetometer/Kconfig
@@ -6,26 +6,21 @@
 menu "Magnetometer sensors"
 
 config AK8975
-	tristate "Asahi Kasei AK8975 3-Axis Magnetometer"
+	tristate "Asahi Kasei AK 3-Axis Magnetometer"
 	depends on I2C
 	depends on GPIOLIB
 	help
-	  Say yes here to build support for Asahi Kasei AK8975 3-Axis
-	  Magnetometer. This driver can also support AK8963, if i2c
-	  device name is identified as ak8963.
+	  Say yes here to build support for Asahi Kasei AK8975, AK8963,
+	  AK09911 or AK09912 3-Axis Magnetometer.
 
 	  To compile this driver as a module, choose M here: the module
 	  will be called ak8975.
 
 config AK09911
 	tristate "Asahi Kasei AK09911 3-axis Compass"
-	depends on I2C
+	select AK8975
 	help
-	  Say yes here to build support for Asahi Kasei AK09911 3-Axis
-	  Magnetometer.
-
-	  To compile this driver as a module, choose M here: the module
-	  will be called ak09911.
+	  Deprecated: AK09911 is now supported by AK8975 driver.
 
 config MAG3110
 	tristate "Freescale MAG3110 3-Axis Magnetometer"
diff --git a/drivers/iio/magnetometer/Makefile b/drivers/iio/magnetometer/Makefile
index b91315e..0f5d3c9 100644
--- a/drivers/iio/magnetometer/Makefile
+++ b/drivers/iio/magnetometer/Makefile
@@ -3,7 +3,6 @@
 #
 
 # When adding new entries keep the list in alphabetical order
-obj-$(CONFIG_AK09911)	+= ak09911.o
 obj-$(CONFIG_AK8975)	+= ak8975.o
 obj-$(CONFIG_MAG3110)	+= mag3110.o
 obj-$(CONFIG_HID_SENSOR_MAGNETOMETER_3D) += hid-sensor-magn-3d.o
diff --git a/drivers/iio/magnetometer/ak09911.c b/drivers/iio/magnetometer/ak09911.c
deleted file mode 100644
index b2bc942..0000000
--- a/drivers/iio/magnetometer/ak09911.c
+++ /dev/null
@@ -1,326 +0,0 @@
-/*
- * AK09911 3-axis compass driver
- * Copyright (c) 2014, Intel Corporation.
- *
- * This program is free software; you can redistribute it and/or modify it
- * under the terms and conditions of the GNU General Public License,
- * version 2, as published by the Free Software Foundation.
- *
- * This program is distributed in the hope it will be useful, but WITHOUT
- * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
- * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
- * more details.
- */
-
-#include <linux/kernel.h>
-#include <linux/module.h>
-#include <linux/init.h>
-#include <linux/types.h>
-#include <linux/slab.h>
-#include <linux/delay.h>
-#include <linux/i2c.h>
-#include <linux/acpi.h>
-#include <linux/iio/iio.h>
-
-#define AK09911_REG_WIA1		0x00
-#define AK09911_REG_WIA2		0x01
-#define AK09911_WIA1_VALUE		0x48
-#define AK09911_WIA2_VALUE		0x05
-
-#define AK09911_REG_ST1			0x10
-#define AK09911_REG_HXL			0x11
-#define AK09911_REG_HXH			0x12
-#define AK09911_REG_HYL			0x13
-#define AK09911_REG_HYH			0x14
-#define AK09911_REG_HZL			0x15
-#define AK09911_REG_HZH			0x16
-
-#define AK09911_REG_ASAX		0x60
-#define AK09911_REG_ASAY		0x61
-#define AK09911_REG_ASAZ		0x62
-
-#define AK09911_REG_CNTL1		0x30
-#define AK09911_REG_CNTL2		0x31
-#define AK09911_REG_CNTL3		0x32
-
-#define AK09911_MODE_SNG_MEASURE	0x01
-#define AK09911_MODE_SELF_TEST		0x10
-#define AK09911_MODE_FUSE_ACCESS	0x1F
-#define AK09911_MODE_POWERDOWN		0x00
-#define AK09911_RESET_DATA		0x01
-
-#define AK09911_REG_CNTL1		0x30
-#define AK09911_REG_CNTL2		0x31
-#define AK09911_REG_CNTL3		0x32
-
-#define AK09911_RAW_TO_GAUSS(asa)	((((asa) + 128) * 6000) / 256)
-
-#define AK09911_MAX_CONVERSION_TIMEOUT_MS	500
-#define AK09911_CONVERSION_DONE_POLL_TIME_MS	10
-
-struct ak09911_data {
-	struct i2c_client	*client;
-	struct mutex		lock;
-	u8			asa[3];
-	long			raw_to_gauss[3];
-};
-
-static const int ak09911_index_to_reg[] = {
-	AK09911_REG_HXL, AK09911_REG_HYL, AK09911_REG_HZL,
-};
-
-static int ak09911_set_mode(struct i2c_client *client, u8 mode)
-{
-	int ret;
-
-	switch (mode) {
-	case AK09911_MODE_SNG_MEASURE:
-	case AK09911_MODE_SELF_TEST:
-	case AK09911_MODE_FUSE_ACCESS:
-	case AK09911_MODE_POWERDOWN:
-		ret = i2c_smbus_write_byte_data(client,
-						AK09911_REG_CNTL2, mode);
-		if (ret < 0) {
-			dev_err(&client->dev, "set_mode error\n");
-			return ret;
-		}
-		/* After mode change wait atleast 100us */
-		usleep_range(100, 500);
-		break;
-	default:
-		dev_err(&client->dev,
-			"%s: Unknown mode(%d).", __func__, mode);
-		return -EINVAL;
-	}
-
-	return ret;
-}
-
-/* Get Sensitivity Adjustment value */
-static int ak09911_get_asa(struct i2c_client *client)
-{
-	struct iio_dev *indio_dev = i2c_get_clientdata(client);
-	struct ak09911_data *data = iio_priv(indio_dev);
-	int ret;
-
-	ret = ak09911_set_mode(client, AK09911_MODE_FUSE_ACCESS);
-	if (ret < 0)
-		return ret;
-
-	/* Get asa data and store in the device data. */
-	ret = i2c_smbus_read_i2c_block_data(client, AK09911_REG_ASAX,
-					    3, data->asa);
-	if (ret < 0) {
-		dev_err(&client->dev, "Not able to read asa data\n");
-		return ret;
-	}
-
-	ret = ak09911_set_mode(client,  AK09911_MODE_POWERDOWN);
-	if (ret < 0)
-		return ret;
-
-	data->raw_to_gauss[0] = AK09911_RAW_TO_GAUSS(data->asa[0]);
-	data->raw_to_gauss[1] = AK09911_RAW_TO_GAUSS(data->asa[1]);
-	data->raw_to_gauss[2] = AK09911_RAW_TO_GAUSS(data->asa[2]);
-
-	return 0;
-}
-
-static int ak09911_verify_chip_id(struct i2c_client *client)
-{
-	u8 wia_val[2];
-	int ret;
-
-	ret = i2c_smbus_read_i2c_block_data(client, AK09911_REG_WIA1,
-					    2, wia_val);
-	if (ret < 0) {
-		dev_err(&client->dev, "Error reading WIA\n");
-		return ret;
-	}
-
-	dev_dbg(&client->dev, "WIA %02x %02x\n", wia_val[0], wia_val[1]);
-
-	if (wia_val[0] != AK09911_WIA1_VALUE ||
-		wia_val[1] != AK09911_WIA2_VALUE) {
-		dev_err(&client->dev, "Device ak09911 not found\n");
-		return -ENODEV;
-	}
-
-	return 0;
-}
-
-static int wait_conversion_complete_polled(struct ak09911_data *data)
-{
-	struct i2c_client *client = data->client;
-	u8 read_status;
-	u32 timeout_ms = AK09911_MAX_CONVERSION_TIMEOUT_MS;
-	int ret;
-
-	/* Wait for the conversion to complete. */
-	while (timeout_ms) {
-		msleep_interruptible(AK09911_CONVERSION_DONE_POLL_TIME_MS);
-		ret = i2c_smbus_read_byte_data(client, AK09911_REG_ST1);
-		if (ret < 0) {
-			dev_err(&client->dev, "Error in reading ST1\n");
-			return ret;
-		}
-		read_status = ret & 0x01;
-		if (read_status)
-			break;
-		timeout_ms -= AK09911_CONVERSION_DONE_POLL_TIME_MS;
-	}
-	if (!timeout_ms) {
-		dev_err(&client->dev, "Conversion timeout happened\n");
-		return -EIO;
-	}
-
-	return read_status;
-}
-
-static int ak09911_read_axis(struct iio_dev *indio_dev, int index, int *val)
-{
-	struct ak09911_data *data = iio_priv(indio_dev);
-	struct i2c_client *client = data->client;
-	int ret;
-
-	mutex_lock(&data->lock);
-
-	ret = ak09911_set_mode(client, AK09911_MODE_SNG_MEASURE);
-	if (ret < 0)
-		goto fn_exit;
-
-	ret = wait_conversion_complete_polled(data);
-	if (ret < 0)
-		goto fn_exit;
-
-	/* Read data */
-	ret = i2c_smbus_read_word_data(client, ak09911_index_to_reg[index]);
-	if (ret < 0) {
-		dev_err(&client->dev, "Read axis data fails\n");
-		goto fn_exit;
-	}
-
-	mutex_unlock(&data->lock);
-
-	/* Clamp to valid range. */
-	*val = sign_extend32(clamp_t(s16, ret, -8192, 8191), 13);
-
-	return IIO_VAL_INT;
-
-fn_exit:
-	mutex_unlock(&data->lock);
-
-	return ret;
-}
-
-static int ak09911_read_raw(struct iio_dev *indio_dev,
-			    struct iio_chan_spec const *chan,
-			    int *val, int *val2,
-			    long mask)
-{
-	struct ak09911_data *data = iio_priv(indio_dev);
-
-	switch (mask) {
-	case IIO_CHAN_INFO_RAW:
-		return ak09911_read_axis(indio_dev, chan->address, val);
-	case IIO_CHAN_INFO_SCALE:
-		*val = 0;
-		*val2 = data->raw_to_gauss[chan->address];
-		return IIO_VAL_INT_PLUS_MICRO;
-	}
-
-	return -EINVAL;
-}
-
-#define AK09911_CHANNEL(axis, index)					\
-	{								\
-		.type = IIO_MAGN,					\
-		.modified = 1,						\
-		.channel2 = IIO_MOD_##axis,				\
-		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |		\
-			     BIT(IIO_CHAN_INFO_SCALE),			\
-		.address = index,					\
-	}
-
-static const struct iio_chan_spec ak09911_channels[] = {
-	AK09911_CHANNEL(X, 0), AK09911_CHANNEL(Y, 1), AK09911_CHANNEL(Z, 2),
-};
-
-static const struct iio_info ak09911_info = {
-	.read_raw = &ak09911_read_raw,
-	.driver_module = THIS_MODULE,
-};
-
-static const struct acpi_device_id ak_acpi_match[] = {
-	{"AK009911", 0},
-	{ },
-};
-MODULE_DEVICE_TABLE(acpi, ak_acpi_match);
-
-static int ak09911_probe(struct i2c_client *client,
-			 const struct i2c_device_id *id)
-{
-	struct iio_dev *indio_dev;
-	struct ak09911_data *data;
-	const char *name;
-	int ret;
-
-	ret = ak09911_verify_chip_id(client);
-	if (ret) {
-		dev_err(&client->dev, "AK00911 not detected\n");
-		return -ENODEV;
-	}
-
-	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
-	if (indio_dev == NULL)
-		return -ENOMEM;
-
-	data = iio_priv(indio_dev);
-	i2c_set_clientdata(client, indio_dev);
-
-	data->client = client;
-	mutex_init(&data->lock);
-
-	ret = ak09911_get_asa(client);
-	if (ret)
-		return ret;
-
-	if (id)
-		name = id->name;
-	else if (ACPI_HANDLE(&client->dev))
-		name = dev_name(&client->dev);
-	else
-		return -ENODEV;
-
-	dev_dbg(&client->dev, "Asahi compass chip %s\n", name);
-
-	indio_dev->dev.parent = &client->dev;
-	indio_dev->channels = ak09911_channels;
-	indio_dev->num_channels = ARRAY_SIZE(ak09911_channels);
-	indio_dev->info = &ak09911_info;
-	indio_dev->modes = INDIO_DIRECT_MODE;
-	indio_dev->name = name;
-
-	return devm_iio_device_register(&client->dev, indio_dev);
-}
-
-static const struct i2c_device_id ak09911_id[] = {
-	{"ak09911", 0},
-	{}
-};
-
-MODULE_DEVICE_TABLE(i2c, ak09911_id);
-
-static struct i2c_driver ak09911_driver = {
-	.driver = {
-		.name	= "ak09911",
-		.acpi_match_table = ACPI_PTR(ak_acpi_match),
-	},
-	.probe		= ak09911_probe,
-	.id_table	= ak09911_id,
-};
-module_i2c_driver(ak09911_driver);
-
-MODULE_AUTHOR("Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>");
-MODULE_LICENSE("GPL v2");
-MODULE_DESCRIPTION("AK09911 Compass driver");
diff --git a/drivers/iio/magnetometer/ak8975.c b/drivers/iio/magnetometer/ak8975.c
index 3ab984c..d109421 100644
--- a/drivers/iio/magnetometer/ak8975.c
+++ b/drivers/iio/magnetometer/ak8975.c
@@ -81,6 +81,58 @@
 #define AK8975_MAX_REGS			AK8975_REG_ASAZ
 
 /*
+ * AK09912 Register definitions
+ */
+#define AK09912_REG_WIA1		0x00
+#define AK09912_REG_WIA2		0x01
+#define AK09912_DEVICE_ID		0x04
+#define AK09911_DEVICE_ID		0x05
+
+#define AK09911_REG_INFO1		0x02
+#define AK09911_REG_INFO2		0x03
+
+#define AK09912_REG_ST1			0x10
+
+#define AK09912_REG_ST1_DRDY_SHIFT	0
+#define AK09912_REG_ST1_DRDY_MASK	(1 << AK09912_REG_ST1_DRDY_SHIFT)
+
+#define AK09912_REG_HXL			0x11
+#define AK09912_REG_HXH			0x12
+#define AK09912_REG_HYL			0x13
+#define AK09912_REG_HYH			0x14
+#define AK09912_REG_HZL			0x15
+#define AK09912_REG_HZH			0x16
+#define AK09912_REG_TMPS		0x17
+
+#define AK09912_REG_ST2			0x18
+#define AK09912_REG_ST2_HOFL_SHIFT	3
+#define AK09912_REG_ST2_HOFL_MASK	(1 << AK09912_REG_ST2_HOFL_SHIFT)
+
+#define AK09912_REG_CNTL1		0x30
+
+#define AK09912_REG_CNTL2		0x31
+#define AK09912_REG_CNTL_MODE_POWER_DOWN	0x00
+#define AK09912_REG_CNTL_MODE_ONCE	0x01
+#define AK09912_REG_CNTL_MODE_SELF_TEST	0x10
+#define AK09912_REG_CNTL_MODE_FUSE_ROM	0x1F
+#define AK09912_REG_CNTL2_MODE_SHIFT	0
+#define AK09912_REG_CNTL2_MODE_MASK	(0x1F << AK09912_REG_CNTL2_MODE_SHIFT)
+
+#define AK09912_REG_CNTL3		0x32
+
+#define AK09912_REG_TS1			0x33
+#define AK09912_REG_TS2			0x34
+#define AK09912_REG_TS3			0x35
+#define AK09912_REG_I2CDIS		0x36
+#define AK09912_REG_TS4			0x37
+
+#define AK09912_REG_ASAX		0x60
+#define AK09912_REG_ASAY		0x61
+#define AK09912_REG_ASAZ		0x62
+
+#define AK09912_MAX_REGS		AK09912_REG_ASAZ
+
+/*
  * Miscellaneous values.
  */
 #define AK8975_MAX_CONVERSION_TIMEOUT	500
@@ -130,22 +182,37 @@ static long ak8975_raw_to_gauss(u16 data)
 }
 
 /*
- * For AK8963, same calculation, but the device is less sensitive:
+ * For AK8963 and AK09911, same calculation, but the device is less sensitive:
  *
  * H is in the range of +-8190.  The magnetometer has a range of
  * +-4912uT.  To go from the raw value to uT is:
  *
  * HuT = H * 4912/8190, or roughly, 6/10, instead of 3/10.
  */
-static long ak8963_raw_to_gauss(u16 data)
+static long ak8963_09911_raw_to_gauss(u16 data)
 {
 	return (((long)data + 128) * 6000) / 256;
 }
 
+/*
+ * For AK09912, same calculation, except the device is more sensitive:
+ *
+ * H is in the range of -32752 to 32752.  The magnetometer has a range of
+ * +-4912uT.  To go from the raw value to uT is:
+ *
+ * HuT = H * 4912/32752, or roughly, 3/20, instead of 3/10.
+ */
+static long ak09912_raw_to_gauss(u16 data)
+{
+	return (((long)data + 128) * 1500) / 256;
+}
+
 /* Compatible Asahi Kasei Compass parts */
 enum asahi_compass_chipset {
 	AK8975,
 	AK8963,
+	AK09911,
+	AK09912,
 	AK_MAX_TYPE
 };
 
@@ -212,7 +279,7 @@ static struct ak_def ak_def_array[AK_MAX_TYPE] = {
 	},
 	{
 		.type = AK8963,
-		.raw_to_gauss = ak8963_raw_to_gauss,
+		.raw_to_gauss = ak8963_09911_raw_to_gauss,
 		.range = 8190,
 		.ctrl_regs = {
 			AK8975_REG_ST1,
@@ -235,6 +302,56 @@ static struct ak_def ak_def_array[AK_MAX_TYPE] = {
 			AK8975_REG_HYL,
 			AK8975_REG_HZL},
 	},
+	{
+		.type = AK09911,
+		.raw_to_gauss = ak8963_09911_raw_to_gauss,
+		.range = 8192,
+		.ctrl_regs = {
+			AK09912_REG_ST1,
+			AK09912_REG_ST2,
+			AK09912_REG_CNTL2,
+			AK09912_REG_ASAX,
+			AK09912_MAX_REGS},
+		.ctrl_masks = {
+			AK09912_REG_ST1_DRDY_MASK,
+			AK09912_REG_ST2_HOFL_MASK,
+			0,
+			AK09912_REG_CNTL2_MODE_MASK},
+		.ctrl_modes = {
+			AK09912_REG_CNTL_MODE_POWER_DOWN,
+			AK09912_REG_CNTL_MODE_ONCE,
+			AK09912_REG_CNTL_MODE_SELF_TEST,
+			AK09912_REG_CNTL_MODE_FUSE_ROM},
+		.data_regs = {
+			AK09912_REG_HXL,
+			AK09912_REG_HYL,
+			AK09912_REG_HZL},
+	},
+	{
+		.type = AK09912,
+		.raw_to_gauss = ak09912_raw_to_gauss,
+		.range = 32752,
+		.ctrl_regs = {
+			AK09912_REG_ST1,
+			AK09912_REG_ST2,
+			AK09912_REG_CNTL2,
+			AK09912_REG_ASAX,
+			AK09912_MAX_REGS},
+		.ctrl_masks = {
+			AK09912_REG_ST1_DRDY_MASK,
+			AK09912_REG_ST2_HOFL_MASK,
+			0,
+			AK09912_REG_CNTL2_MODE_MASK},
+		.ctrl_modes = {
+			AK09912_REG_CNTL_MODE_POWER_DOWN,
+			AK09912_REG_CNTL_MODE_ONCE,
+			AK09912_REG_CNTL_MODE_SELF_TEST,
+			AK09912_REG_CNTL_MODE_FUSE_ROM},
+		.data_regs = {
+			AK09912_REG_HXL,
+			AK09912_REG_HYL,
+			AK09912_REG_HZL},
+	}
 };
 
 /*
@@ -255,6 +372,52 @@ struct ak8975_data {
 };
 
 /*
+ * Return 0 if the i2c device is the one we expect.
+ * return a negative error number otherwise
+ */
+static int ak8975_who_i_am(struct i2c_client *client,
+			   enum asahi_compass_chipset type)
+{
+	u8 wia_val[2];
+	int ret;
+
+	/*
+	 * Signature for each device:
+	 * Device   |  WIA1      |  WIA2
+	 * AK09912  |  DEVICE_ID |  AK09912_DEVICE_ID
+	 * AK09911  |  DEVICE_ID |  AK09911_DEVICE_ID
+	 * AK8975   |  DEVICE_ID |  NA
+	 * AK8963   |  DEVICE_ID |  NA
+	 */
+	ret = i2c_smbus_read_i2c_block_data(client, AK09912_REG_WIA1,
+					    2, wia_val);
+	if (ret < 0) {
+		dev_err(&client->dev, "Error reading WIA\n");
+		return ret;
+	}
+
+	if (wia_val[0] != AK8975_DEVICE_ID)
+		return -ENODEV;
+
+	switch (type) {
+	case AK8975:
+	case AK8963:
+		return 0;
+	case AK09911:
+		if (wia_val[1] == AK09911_DEVICE_ID)
+			return 0;
+		break;
+	case AK09912:
+		if (wia_val[1] == AK09912_DEVICE_ID)
+			return 0;
+		break;
+	default:
+		dev_err(&client->dev, "Type %d unknown\n", type);
+	}
+	return -ENODEV;
+}
+
+/*
  * Helper function to write to CNTL register.
  */
 static int ak8975_set_mode(struct ak8975_data *data, enum ak_ctrl_mode mode)
@@ -329,21 +492,8 @@ static int ak8975_setup(struct i2c_client *client)
 {
 	struct iio_dev *indio_dev = i2c_get_clientdata(client);
 	struct ak8975_data *data = iio_priv(indio_dev);
-	u8 device_id;
 	int ret;
 
-	/* Confirm that the device we're talking to is really an AK8975. */
-	ret = i2c_smbus_read_byte_data(client, AK8975_REG_WIA);
-	if (ret < 0) {
-		dev_err(&client->dev, "Error reading WIA\n");
-		return ret;
-	}
-	device_id = ret;
-	if (device_id != AK8975_DEVICE_ID) {
-		dev_err(&client->dev, "Device ak8975 not found\n");
-		return -ENODEV;
-	}
-
 	/* Write the fused rom access mode. */
 	ret = ak8975_set_mode(data, FUSE_ROM);
 	if (ret < 0) {
@@ -554,6 +704,8 @@ static const struct acpi_device_id ak_acpi_match[] = {
 	{"AK8975", AK8975},
 	{"AK8963", AK8963},
 	{"INVN6500", AK8963},
+	{"AK09911", AK09911},
+	{"AK09912", AK09912},
 	{ },
 };
 MODULE_DEVICE_TABLE(acpi, ak_acpi_match);
@@ -633,6 +785,11 @@ static int ak8975_probe(struct i2c_client *client,
 	}
 
 	data->def = &ak_def_array[chipset];
+	err = ak8975_who_i_am(client, data->def->type);
+	if (err < 0) {
+		dev_err(&client->dev, "Unexpected device\n");
+		return err;
+	}
 	dev_dbg(&client->dev, "Asahi compass chip %s\n", name);
 
 	/* Perform some basic start-of-day setup of the device. */
@@ -655,6 +812,8 @@ static int ak8975_probe(struct i2c_client *client,
 static const struct i2c_device_id ak8975_id[] = {
 	{"ak8975", AK8975},
 	{"ak8963", AK8963},
+	{"ak09911", AK09911},
+	{"ak09912", AK09912},
 	{}
 };
 
@@ -665,6 +824,10 @@ static const struct of_device_id ak8975_of_match[] = {
 	{ .compatible = "ak8975", },
 	{ .compatible = "asahi-kasei,ak8963", },
 	{ .compatible = "ak8963", },
+	{ .compatible = "asahi-kasei,ak09911", },
+	{ .compatible = "ak09911", },
+	{ .compatible = "asahi-kasei,ak09912", },
+	{ .compatible = "ak09912", },
 	{}
 };
 MODULE_DEVICE_TABLE(of, ak8975_of_match);
-- 
2.1.0.rc2.206.gedb03e5

Re: [PATCH v4 3/3] iio: ak8975: add ak09911 and ak09912 support

[Hartmut Knaack]

Gwendal Grignou schrieb am 24.11.2014 um 09:44:
> Add 2 new definition entries to support ak0991x compass.
> Add a more advanced function to check we are dealing with the
> expected device.
> Remove standalone driver for ak09911.
> 
> Signed-off-by: Gwendal Grignou <gwendal@chromium.org>
> Tested-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Reviewed-by: Hartmut Knaack <knaack.h@gmx.de>
> ---
>  added static as requested by kbuild test robot.
> 
>  drivers/iio/magnetometer/Kconfig   |  15 +-
>  drivers/iio/magnetometer/Makefile  |   1 -
>  drivers/iio/magnetometer/ak09911.c | 326 -------------------------------------
>  drivers/iio/magnetometer/ak8975.c  | 195 ++++++++++++++++++++--
>  4 files changed, 184 insertions(+), 353 deletions(-)
>  delete mode 100644 drivers/iio/magnetometer/ak09911.c
> 
> diff --git a/drivers/iio/magnetometer/Kconfig b/drivers/iio/magnetometer/Kconfig
> index b2dba9e..4c7a4c5 100644
> --- a/drivers/iio/magnetometer/Kconfig
> +++ b/drivers/iio/magnetometer/Kconfig
> @@ -6,26 +6,21 @@
>  menu "Magnetometer sensors"
>  
>  config AK8975
> -	tristate "Asahi Kasei AK8975 3-Axis Magnetometer"
> +	tristate "Asahi Kasei AK 3-Axis Magnetometer"
>  	depends on I2C
>  	depends on GPIOLIB
>  	help
> -	  Say yes here to build support for Asahi Kasei AK8975 3-Axis
> -	  Magnetometer. This driver can also support AK8963, if i2c
> -	  device name is identified as ak8963.
> +	  Say yes here to build support for Asahi Kasei AK8975, AK8963,
> +	  AK09911 or AK09912 3-Axis Magnetometer.
>  
>  	  To compile this driver as a module, choose M here: the module
>  	  will be called ak8975.
>  
>  config AK09911
>  	tristate "Asahi Kasei AK09911 3-axis Compass"
> -	depends on I2C
> +	select AK8975
>  	help
> -	  Say yes here to build support for Asahi Kasei AK09911 3-Axis
> -	  Magnetometer.
> -
> -	  To compile this driver as a module, choose M here: the module
> -	  will be called ak09911.
> +	  Deprecated: AK09911 is now supported by AK8975 driver.
>  
>  config MAG3110
>  	tristate "Freescale MAG3110 3-Axis Magnetometer"
> diff --git a/drivers/iio/magnetometer/Makefile b/drivers/iio/magnetometer/Makefile
> index b91315e..0f5d3c9 100644
> --- a/drivers/iio/magnetometer/Makefile
> +++ b/drivers/iio/magnetometer/Makefile
> @@ -3,7 +3,6 @@
>  #
>  
>  # When adding new entries keep the list in alphabetical order
> -obj-$(CONFIG_AK09911)	+= ak09911.o
>  obj-$(CONFIG_AK8975)	+= ak8975.o
>  obj-$(CONFIG_MAG3110)	+= mag3110.o
>  obj-$(CONFIG_HID_SENSOR_MAGNETOMETER_3D) += hid-sensor-magn-3d.o
> diff --git a/drivers/iio/magnetometer/ak09911.c b/drivers/iio/magnetometer/ak09911.c
> deleted file mode 100644
> index b2bc942..0000000
> --- a/drivers/iio/magnetometer/ak09911.c
> +++ /dev/null
> @@ -1,326 +0,0 @@
> -/*
> - * AK09911 3-axis compass driver
> - * Copyright (c) 2014, Intel Corporation.
> - *
> - * This program is free software; you can redistribute it and/or modify it
> - * under the terms and conditions of the GNU General Public License,
> - * version 2, as published by the Free Software Foundation.
> - *
> - * This program is distributed in the hope it will be useful, but WITHOUT
> - * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
> - * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
> - * more details.
> - */
> -
> -#include <linux/kernel.h>
> -#include <linux/module.h>
> -#include <linux/init.h>
> -#include <linux/types.h>
> -#include <linux/slab.h>
> -#include <linux/delay.h>
> -#include <linux/i2c.h>
> -#include <linux/acpi.h>
> -#include <linux/iio/iio.h>
> -
> -#define AK09911_REG_WIA1		0x00
> -#define AK09911_REG_WIA2		0x01
> -#define AK09911_WIA1_VALUE		0x48
> -#define AK09911_WIA2_VALUE		0x05
> -
> -#define AK09911_REG_ST1			0x10
> -#define AK09911_REG_HXL			0x11
> -#define AK09911_REG_HXH			0x12
> -#define AK09911_REG_HYL			0x13
> -#define AK09911_REG_HYH			0x14
> -#define AK09911_REG_HZL			0x15
> -#define AK09911_REG_HZH			0x16
> -
> -#define AK09911_REG_ASAX		0x60
> -#define AK09911_REG_ASAY		0x61
> -#define AK09911_REG_ASAZ		0x62
> -
> -#define AK09911_REG_CNTL1		0x30
> -#define AK09911_REG_CNTL2		0x31
> -#define AK09911_REG_CNTL3		0x32
> -
> -#define AK09911_MODE_SNG_MEASURE	0x01
> -#define AK09911_MODE_SELF_TEST		0x10
> -#define AK09911_MODE_FUSE_ACCESS	0x1F
> -#define AK09911_MODE_POWERDOWN		0x00
> -#define AK09911_RESET_DATA		0x01
> -
> -#define AK09911_REG_CNTL1		0x30
> -#define AK09911_REG_CNTL2		0x31
> -#define AK09911_REG_CNTL3		0x32
> -
> -#define AK09911_RAW_TO_GAUSS(asa)	((((asa) + 128) * 6000) / 256)
> -
> -#define AK09911_MAX_CONVERSION_TIMEOUT_MS	500
> -#define AK09911_CONVERSION_DONE_POLL_TIME_MS	10
> -
> -struct ak09911_data {
> -	struct i2c_client	*client;
> -	struct mutex		lock;
> -	u8			asa[3];
> -	long			raw_to_gauss[3];
> -};
> -
> -static const int ak09911_index_to_reg[] = {
> -	AK09911_REG_HXL, AK09911_REG_HYL, AK09911_REG_HZL,
> -};
> -
> -static int ak09911_set_mode(struct i2c_client *client, u8 mode)
> -{
> -	int ret;
> -
> -	switch (mode) {
> -	case AK09911_MODE_SNG_MEASURE:
> -	case AK09911_MODE_SELF_TEST:
> -	case AK09911_MODE_FUSE_ACCESS:
> -	case AK09911_MODE_POWERDOWN:
> -		ret = i2c_smbus_write_byte_data(client,
> -						AK09911_REG_CNTL2, mode);
> -		if (ret < 0) {
> -			dev_err(&client->dev, "set_mode error\n");
> -			return ret;
> -		}
> -		/* After mode change wait atleast 100us */
> -		usleep_range(100, 500);
> -		break;
> -	default:
> -		dev_err(&client->dev,
> -			"%s: Unknown mode(%d).", __func__, mode);
> -		return -EINVAL;
> -	}
> -
> -	return ret;
> -}
> -
> -/* Get Sensitivity Adjustment value */
> -static int ak09911_get_asa(struct i2c_client *client)
> -{
> -	struct iio_dev *indio_dev = i2c_get_clientdata(client);
> -	struct ak09911_data *data = iio_priv(indio_dev);
> -	int ret;
> -
> -	ret = ak09911_set_mode(client, AK09911_MODE_FUSE_ACCESS);
> -	if (ret < 0)
> -		return ret;
> -
> -	/* Get asa data and store in the device data. */
> -	ret = i2c_smbus_read_i2c_block_data(client, AK09911_REG_ASAX,
> -					    3, data->asa);
> -	if (ret < 0) {
> -		dev_err(&client->dev, "Not able to read asa data\n");
> -		return ret;
> -	}
> -
> -	ret = ak09911_set_mode(client,  AK09911_MODE_POWERDOWN);
> -	if (ret < 0)
> -		return ret;
> -
> -	data->raw_to_gauss[0] = AK09911_RAW_TO_GAUSS(data->asa[0]);
> -	data->raw_to_gauss[1] = AK09911_RAW_TO_GAUSS(data->asa[1]);
> -	data->raw_to_gauss[2] = AK09911_RAW_TO_GAUSS(data->asa[2]);
> -
> -	return 0;
> -}
> -
> -static int ak09911_verify_chip_id(struct i2c_client *client)
> -{
> -	u8 wia_val[2];
> -	int ret;
> -
> -	ret = i2c_smbus_read_i2c_block_data(client, AK09911_REG_WIA1,
> -					    2, wia_val);
> -	if (ret < 0) {
> -		dev_err(&client->dev, "Error reading WIA\n");
> -		return ret;
> -	}
> -
> -	dev_dbg(&client->dev, "WIA %02x %02x\n", wia_val[0], wia_val[1]);
> -
> -	if (wia_val[0] != AK09911_WIA1_VALUE ||
> -		wia_val[1] != AK09911_WIA2_VALUE) {
> -		dev_err(&client->dev, "Device ak09911 not found\n");
> -		return -ENODEV;
> -	}
> -
> -	return 0;
> -}
> -
> -static int wait_conversion_complete_polled(struct ak09911_data *data)
> -{
> -	struct i2c_client *client = data->client;
> -	u8 read_status;
> -	u32 timeout_ms = AK09911_MAX_CONVERSION_TIMEOUT_MS;
> -	int ret;
> -
> -	/* Wait for the conversion to complete. */
> -	while (timeout_ms) {
> -		msleep_interruptible(AK09911_CONVERSION_DONE_POLL_TIME_MS);
> -		ret = i2c_smbus_read_byte_data(client, AK09911_REG_ST1);
> -		if (ret < 0) {
> -			dev_err(&client->dev, "Error in reading ST1\n");
> -			return ret;
> -		}
> -		read_status = ret & 0x01;
> -		if (read_status)
> -			break;
> -		timeout_ms -= AK09911_CONVERSION_DONE_POLL_TIME_MS;
> -	}
> -	if (!timeout_ms) {
> -		dev_err(&client->dev, "Conversion timeout happened\n");
> -		return -EIO;
> -	}
> -
> -	return read_status;
> -}
> -
> -static int ak09911_read_axis(struct iio_dev *indio_dev, int index, int *val)
> -{
> -	struct ak09911_data *data = iio_priv(indio_dev);
> -	struct i2c_client *client = data->client;
> -	int ret;
> -
> -	mutex_lock(&data->lock);
> -
> -	ret = ak09911_set_mode(client, AK09911_MODE_SNG_MEASURE);
> -	if (ret < 0)
> -		goto fn_exit;
> -
> -	ret = wait_conversion_complete_polled(data);
> -	if (ret < 0)
> -		goto fn_exit;
> -
> -	/* Read data */
> -	ret = i2c_smbus_read_word_data(client, ak09911_index_to_reg[index]);
> -	if (ret < 0) {
> -		dev_err(&client->dev, "Read axis data fails\n");
> -		goto fn_exit;
> -	}
> -
> -	mutex_unlock(&data->lock);
> -
> -	/* Clamp to valid range. */
> -	*val = sign_extend32(clamp_t(s16, ret, -8192, 8191), 13);
> -
> -	return IIO_VAL_INT;
> -
> -fn_exit:
> -	mutex_unlock(&data->lock);
> -
> -	return ret;
> -}
> -
> -static int ak09911_read_raw(struct iio_dev *indio_dev,
> -			    struct iio_chan_spec const *chan,
> -			    int *val, int *val2,
> -			    long mask)
> -{
> -	struct ak09911_data *data = iio_priv(indio_dev);
> -
> -	switch (mask) {
> -	case IIO_CHAN_INFO_RAW:
> -		return ak09911_read_axis(indio_dev, chan->address, val);
> -	case IIO_CHAN_INFO_SCALE:
> -		*val = 0;
> -		*val2 = data->raw_to_gauss[chan->address];
> -		return IIO_VAL_INT_PLUS_MICRO;
> -	}
> -
> -	return -EINVAL;
> -}
> -
> -#define AK09911_CHANNEL(axis, index)					\
> -	{								\
> -		.type = IIO_MAGN,					\
> -		.modified = 1,						\
> -		.channel2 = IIO_MOD_##axis,				\
> -		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |		\
> -			     BIT(IIO_CHAN_INFO_SCALE),			\
> -		.address = index,					\
> -	}
> -
> -static const struct iio_chan_spec ak09911_channels[] = {
> -	AK09911_CHANNEL(X, 0), AK09911_CHANNEL(Y, 1), AK09911_CHANNEL(Z, 2),
> -};
> -
> -static const struct iio_info ak09911_info = {
> -	.read_raw = &ak09911_read_raw,
> -	.driver_module = THIS_MODULE,
> -};
> -
> -static const struct acpi_device_id ak_acpi_match[] = {
> -	{"AK009911", 0},
> -	{ },
> -};
> -MODULE_DEVICE_TABLE(acpi, ak_acpi_match);
> -
> -static int ak09911_probe(struct i2c_client *client,
> -			 const struct i2c_device_id *id)
> -{
> -	struct iio_dev *indio_dev;
> -	struct ak09911_data *data;
> -	const char *name;
> -	int ret;
> -
> -	ret = ak09911_verify_chip_id(client);
> -	if (ret) {
> -		dev_err(&client->dev, "AK00911 not detected\n");
> -		return -ENODEV;
> -	}
> -
> -	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
> -	if (indio_dev == NULL)
> -		return -ENOMEM;
> -
> -	data = iio_priv(indio_dev);
> -	i2c_set_clientdata(client, indio_dev);
> -
> -	data->client = client;
> -	mutex_init(&data->lock);
> -
> -	ret = ak09911_get_asa(client);
> -	if (ret)
> -		return ret;
> -
> -	if (id)
> -		name = id->name;
> -	else if (ACPI_HANDLE(&client->dev))
> -		name = dev_name(&client->dev);
> -	else
> -		return -ENODEV;
> -
> -	dev_dbg(&client->dev, "Asahi compass chip %s\n", name);
> -
> -	indio_dev->dev.parent = &client->dev;
> -	indio_dev->channels = ak09911_channels;
> -	indio_dev->num_channels = ARRAY_SIZE(ak09911_channels);
> -	indio_dev->info = &ak09911_info;
> -	indio_dev->modes = INDIO_DIRECT_MODE;
> -	indio_dev->name = name;
> -
> -	return devm_iio_device_register(&client->dev, indio_dev);
> -}
> -
> -static const struct i2c_device_id ak09911_id[] = {
> -	{"ak09911", 0},
> -	{}
> -};
> -
> -MODULE_DEVICE_TABLE(i2c, ak09911_id);
> -
> -static struct i2c_driver ak09911_driver = {
> -	.driver = {
> -		.name	= "ak09911",
> -		.acpi_match_table = ACPI_PTR(ak_acpi_match),
> -	},
> -	.probe		= ak09911_probe,
> -	.id_table	= ak09911_id,
> -};
> -module_i2c_driver(ak09911_driver);
> -
> -MODULE_AUTHOR("Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>");
> -MODULE_LICENSE("GPL v2");
> -MODULE_DESCRIPTION("AK09911 Compass driver");
> diff --git a/drivers/iio/magnetometer/ak8975.c b/drivers/iio/magnetometer/ak8975.c
> index 3ab984c..d109421 100644
> --- a/drivers/iio/magnetometer/ak8975.c
> +++ b/drivers/iio/magnetometer/ak8975.c
> @@ -81,6 +81,58 @@
>  #define AK8975_MAX_REGS			AK8975_REG_ASAZ
>  
>  /*
> + * AK09912 Register definitions
> + */
> +#define AK09912_REG_WIA1		0x00
> +#define AK09912_REG_WIA2		0x01
> +#define AK09912_DEVICE_ID		0x04
> +#define AK09911_DEVICE_ID		0x05
> +
> +#define AK09911_REG_INFO1		0x02
> +#define AK09911_REG_INFO2		0x03
> +
> +#define AK09912_REG_ST1			0x10
> +
> +#define AK09912_REG_ST1_DRDY_SHIFT	0
> +#define AK09912_REG_ST1_DRDY_MASK	(1 << AK09912_REG_ST1_DRDY_SHIFT)
> +
> +#define AK09912_REG_HXL			0x11
> +#define AK09912_REG_HXH			0x12
> +#define AK09912_REG_HYL			0x13
> +#define AK09912_REG_HYH			0x14
> +#define AK09912_REG_HZL			0x15
> +#define AK09912_REG_HZH			0x16
> +#define AK09912_REG_TMPS		0x17
> +
> +#define AK09912_REG_ST2			0x18
> +#define AK09912_REG_ST2_HOFL_SHIFT	3
> +#define AK09912_REG_ST2_HOFL_MASK	(1 << AK09912_REG_ST2_HOFL_SHIFT)
> +
> +#define AK09912_REG_CNTL1		0x30
> +
> +#define AK09912_REG_CNTL2		0x31
> +#define AK09912_REG_CNTL_MODE_POWER_DOWN	0x00
> +#define AK09912_REG_CNTL_MODE_ONCE	0x01
> +#define AK09912_REG_CNTL_MODE_SELF_TEST	0x10
> +#define AK09912_REG_CNTL_MODE_FUSE_ROM	0x1F
> +#define AK09912_REG_CNTL2_MODE_SHIFT	0
> +#define AK09912_REG_CNTL2_MODE_MASK	(0x1F << AK09912_REG_CNTL2_MODE_SHIFT)
> +
> +#define AK09912_REG_CNTL3		0x32
> +
> +#define AK09912_REG_TS1			0x33
> +#define AK09912_REG_TS2			0x34
> +#define AK09912_REG_TS3			0x35
> +#define AK09912_REG_I2CDIS		0x36
> +#define AK09912_REG_TS4			0x37
> +
> +#define AK09912_REG_ASAX		0x60
> +#define AK09912_REG_ASAY		0x61
> +#define AK09912_REG_ASAZ		0x62
> +
> +#define AK09912_MAX_REGS		AK09912_REG_ASAZ
> +
> +/*
>   * Miscellaneous values.
>   */
>  #define AK8975_MAX_CONVERSION_TIMEOUT	500
> @@ -130,22 +182,37 @@ static long ak8975_raw_to_gauss(u16 data)
>  }
>  
>  /*
> - * For AK8963, same calculation, but the device is less sensitive:
> + * For AK8963 and AK09911, same calculation, but the device is less sensitive:
>   *
>   * H is in the range of +-8190.  The magnetometer has a range of
>   * +-4912uT.  To go from the raw value to uT is:
>   *
>   * HuT = H * 4912/8190, or roughly, 6/10, instead of 3/10.
>   */
> -static long ak8963_raw_to_gauss(u16 data)
> +static long ak8963_09911_raw_to_gauss(u16 data)
>  {
>  	return (((long)data + 128) * 6000) / 256;
>  }
>  
> +/*
> + * For AK09912, same calculation, except the device is more sensitive:
> + *
> + * H is in the range of -32752 to 32752.  The magnetometer has a range of
> + * +-4912uT.  To go from the raw value to uT is:
> + *
> + * HuT = H * 4912/32752, or roughly, 3/20, instead of 3/10.
> + */
> +static long ak09912_raw_to_gauss(u16 data)
> +{
> +	return (((long)data + 128) * 1500) / 256;
> +}
> +
>  /* Compatible Asahi Kasei Compass parts */
>  enum asahi_compass_chipset {
>  	AK8975,
>  	AK8963,
> +	AK09911,
> +	AK09912,
>  	AK_MAX_TYPE
>  };
>  
> @@ -212,7 +279,7 @@ static struct ak_def ak_def_array[AK_MAX_TYPE] = {
>  	},
>  	{
>  		.type = AK8963,
> -		.raw_to_gauss = ak8963_raw_to_gauss,
> +		.raw_to_gauss = ak8963_09911_raw_to_gauss,
>  		.range = 8190,
>  		.ctrl_regs = {
>  			AK8975_REG_ST1,
> @@ -235,6 +302,56 @@ static struct ak_def ak_def_array[AK_MAX_TYPE] = {
>  			AK8975_REG_HYL,
>  			AK8975_REG_HZL},
>  	},
> +	{
> +		.type = AK09911,
> +		.raw_to_gauss = ak8963_09911_raw_to_gauss,
> +		.range = 8192,
> +		.ctrl_regs = {
> +			AK09912_REG_ST1,
> +			AK09912_REG_ST2,
> +			AK09912_REG_CNTL2,
> +			AK09912_REG_ASAX,
> +			AK09912_MAX_REGS},
> +		.ctrl_masks = {
> +			AK09912_REG_ST1_DRDY_MASK,
> +			AK09912_REG_ST2_HOFL_MASK,
> +			0,
> +			AK09912_REG_CNTL2_MODE_MASK},
> +		.ctrl_modes = {
> +			AK09912_REG_CNTL_MODE_POWER_DOWN,
> +			AK09912_REG_CNTL_MODE_ONCE,
> +			AK09912_REG_CNTL_MODE_SELF_TEST,
> +			AK09912_REG_CNTL_MODE_FUSE_ROM},
> +		.data_regs = {
> +			AK09912_REG_HXL,
> +			AK09912_REG_HYL,
> +			AK09912_REG_HZL},
> +	},
> +	{
> +		.type = AK09912,
> +		.raw_to_gauss = ak09912_raw_to_gauss,
> +		.range = 32752,
> +		.ctrl_regs = {
> +			AK09912_REG_ST1,
> +			AK09912_REG_ST2,
> +			AK09912_REG_CNTL2,
> +			AK09912_REG_ASAX,
> +			AK09912_MAX_REGS},
> +		.ctrl_masks = {
> +			AK09912_REG_ST1_DRDY_MASK,
> +			AK09912_REG_ST2_HOFL_MASK,
> +			0,
> +			AK09912_REG_CNTL2_MODE_MASK},
> +		.ctrl_modes = {
> +			AK09912_REG_CNTL_MODE_POWER_DOWN,
> +			AK09912_REG_CNTL_MODE_ONCE,
> +			AK09912_REG_CNTL_MODE_SELF_TEST,
> +			AK09912_REG_CNTL_MODE_FUSE_ROM},
> +		.data_regs = {
> +			AK09912_REG_HXL,
> +			AK09912_REG_HYL,
> +			AK09912_REG_HZL},
> +	}
>  };
>  
>  /*
> @@ -255,6 +372,52 @@ struct ak8975_data {
>  };
>  
>  /*
> + * Return 0 if the i2c device is the one we expect.
> + * return a negative error number otherwise
> + */
> +static int ak8975_who_i_am(struct i2c_client *client,
> +			   enum asahi_compass_chipset type)
> +{
> +	u8 wia_val[2];
> +	int ret;
> +
> +	/*
> +	 * Signature for each device:
> +	 * Device   |  WIA1      |  WIA2
> +	 * AK09912  |  DEVICE_ID |  AK09912_DEVICE_ID
> +	 * AK09911  |  DEVICE_ID |  AK09911_DEVICE_ID
> +	 * AK8975   |  DEVICE_ID |  NA
> +	 * AK8963   |  DEVICE_ID |  NA
> +	 */
> +	ret = i2c_smbus_read_i2c_block_data(client, AK09912_REG_WIA1,
> +					    2, wia_val);
> +	if (ret < 0) {
> +		dev_err(&client->dev, "Error reading WIA\n");
> +		return ret;
> +	}
> +
> +	if (wia_val[0] != AK8975_DEVICE_ID)
> +		return -ENODEV;
> +
> +	switch (type) {
> +	case AK8975:
> +	case AK8963:
> +		return 0;
> +	case AK09911:
> +		if (wia_val[1] == AK09911_DEVICE_ID)
> +			return 0;
> +		break;
> +	case AK09912:
> +		if (wia_val[1] == AK09912_DEVICE_ID)
> +			return 0;
> +		break;
> +	default:
> +		dev_err(&client->dev, "Type %d unknown\n", type);
> +	}
> +	return -ENODEV;
> +}
> +
> +/*
>   * Helper function to write to CNTL register.
>   */
>  static int ak8975_set_mode(struct ak8975_data *data, enum ak_ctrl_mode mode)
> @@ -329,21 +492,8 @@ static int ak8975_setup(struct i2c_client *client)
>  {
>  	struct iio_dev *indio_dev = i2c_get_clientdata(client);
>  	struct ak8975_data *data = iio_priv(indio_dev);
> -	u8 device_id;
>  	int ret;
>  
> -	/* Confirm that the device we're talking to is really an AK8975. */
> -	ret = i2c_smbus_read_byte_data(client, AK8975_REG_WIA);
> -	if (ret < 0) {
> -		dev_err(&client->dev, "Error reading WIA\n");
> -		return ret;
> -	}
> -	device_id = ret;
> -	if (device_id != AK8975_DEVICE_ID) {
> -		dev_err(&client->dev, "Device ak8975 not found\n");
> -		return -ENODEV;
> -	}
> -
>  	/* Write the fused rom access mode. */
>  	ret = ak8975_set_mode(data, FUSE_ROM);
>  	if (ret < 0) {
> @@ -554,6 +704,8 @@ static const struct acpi_device_id ak_acpi_match[] = {
>  	{"AK8975", AK8975},
>  	{"AK8963", AK8963},
>  	{"INVN6500", AK8963},
> +	{"AK09911", AK09911},
> +	{"AK09912", AK09912},
>  	{ },
>  };
>  MODULE_DEVICE_TABLE(acpi, ak_acpi_match);
> @@ -633,6 +785,11 @@ static int ak8975_probe(struct i2c_client *client,
>  	}
>  
>  	data->def = &ak_def_array[chipset];
> +	err = ak8975_who_i_am(client, data->def->type);
> +	if (err < 0) {
> +		dev_err(&client->dev, "Unexpected device\n");
> +		return err;
> +	}
>  	dev_dbg(&client->dev, "Asahi compass chip %s\n", name);
>  
>  	/* Perform some basic start-of-day setup of the device. */
> @@ -655,6 +812,8 @@ static int ak8975_probe(struct i2c_client *client,
>  static const struct i2c_device_id ak8975_id[] = {
>  	{"ak8975", AK8975},
>  	{"ak8963", AK8963},
> +	{"ak09911", AK09911},
> +	{"ak09912", AK09912},
>  	{}
>  };
>  
> @@ -665,6 +824,10 @@ static const struct of_device_id ak8975_of_match[] = {
>  	{ .compatible = "ak8975", },
>  	{ .compatible = "asahi-kasei,ak8963", },
>  	{ .compatible = "ak8963", },
> +	{ .compatible = "asahi-kasei,ak09911", },
> +	{ .compatible = "ak09911", },
> +	{ .compatible = "asahi-kasei,ak09912", },
> +	{ .compatible = "ak09912", },
>  	{}
>  };
>  MODULE_DEVICE_TABLE(of, ak8975_of_match);
> 

Re: [PATCH v4 3/3] iio: ak8975: add ak09911 and ak09912 support

[Jonathan Cameron]

On 21/11/14 18:45, Gwendal Grignou wrote:
> Add 2 new definition entries to support ak0991x compass.
> Add a more advanced function to check we are dealing with the
> expected device.
> Remove standalone driver for ak09911.
> 
> Tested-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
> Signed-off-by: Gwendal Grignou <gwendal@chromium.org>
Applied the equivalent changes with hartmut's alignment stuff as well for patch 2.
> ---
>  drivers/iio/magnetometer/Kconfig   |  15 +-
>  drivers/iio/magnetometer/Makefile  |   1 -
>  drivers/iio/magnetometer/ak09911.c | 326 -------------------------------------
>  drivers/iio/magnetometer/ak8975.c  | 195 ++++++++++++++++++++--
>  4 files changed, 184 insertions(+), 353 deletions(-)
>  delete mode 100644 drivers/iio/magnetometer/ak09911.c
> 
> diff --git a/drivers/iio/magnetometer/Kconfig b/drivers/iio/magnetometer/Kconfig
> index b2dba9e..4c7a4c5 100644
> --- a/drivers/iio/magnetometer/Kconfig
> +++ b/drivers/iio/magnetometer/Kconfig
> @@ -6,26 +6,21 @@
>  menu "Magnetometer sensors"
>  
>  config AK8975
> -	tristate "Asahi Kasei AK8975 3-Axis Magnetometer"
> +	tristate "Asahi Kasei AK 3-Axis Magnetometer"
>  	depends on I2C
>  	depends on GPIOLIB
>  	help
> -	  Say yes here to build support for Asahi Kasei AK8975 3-Axis
> -	  Magnetometer. This driver can also support AK8963, if i2c
> -	  device name is identified as ak8963.
> +	  Say yes here to build support for Asahi Kasei AK8975, AK8963,
> +	  AK09911 or AK09912 3-Axis Magnetometer.
>  
>  	  To compile this driver as a module, choose M here: the module
>  	  will be called ak8975.
>  
>  config AK09911
>  	tristate "Asahi Kasei AK09911 3-axis Compass"
> -	depends on I2C
> +	select AK8975
>  	help
> -	  Say yes here to build support for Asahi Kasei AK09911 3-Axis
> -	  Magnetometer.
> -
> -	  To compile this driver as a module, choose M here: the module
> -	  will be called ak09911.
> +	  Deprecated: AK09911 is now supported by AK8975 driver.
>  
>  config MAG3110
>  	tristate "Freescale MAG3110 3-Axis Magnetometer"
> diff --git a/drivers/iio/magnetometer/Makefile b/drivers/iio/magnetometer/Makefile
> index b91315e..0f5d3c9 100644
> --- a/drivers/iio/magnetometer/Makefile
> +++ b/drivers/iio/magnetometer/Makefile
> @@ -3,7 +3,6 @@
>  #
>  
>  # When adding new entries keep the list in alphabetical order
> -obj-$(CONFIG_AK09911)	+= ak09911.o
>  obj-$(CONFIG_AK8975)	+= ak8975.o
>  obj-$(CONFIG_MAG3110)	+= mag3110.o
>  obj-$(CONFIG_HID_SENSOR_MAGNETOMETER_3D) += hid-sensor-magn-3d.o
> diff --git a/drivers/iio/magnetometer/ak09911.c b/drivers/iio/magnetometer/ak09911.c
> deleted file mode 100644
> index b2bc942..0000000
> --- a/drivers/iio/magnetometer/ak09911.c
> +++ /dev/null
> @@ -1,326 +0,0 @@
> -/*
> - * AK09911 3-axis compass driver
> - * Copyright (c) 2014, Intel Corporation.
> - *
> - * This program is free software; you can redistribute it and/or modify it
> - * under the terms and conditions of the GNU General Public License,
> - * version 2, as published by the Free Software Foundation.
> - *
> - * This program is distributed in the hope it will be useful, but WITHOUT
> - * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
> - * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
> - * more details.
> - */
> -
> -#include <linux/kernel.h>
> -#include <linux/module.h>
> -#include <linux/init.h>
> -#include <linux/types.h>
> -#include <linux/slab.h>
> -#include <linux/delay.h>
> -#include <linux/i2c.h>
> -#include <linux/acpi.h>
> -#include <linux/iio/iio.h>
> -
> -#define AK09911_REG_WIA1		0x00
> -#define AK09911_REG_WIA2		0x01
> -#define AK09911_WIA1_VALUE		0x48
> -#define AK09911_WIA2_VALUE		0x05
> -
> -#define AK09911_REG_ST1			0x10
> -#define AK09911_REG_HXL			0x11
> -#define AK09911_REG_HXH			0x12
> -#define AK09911_REG_HYL			0x13
> -#define AK09911_REG_HYH			0x14
> -#define AK09911_REG_HZL			0x15
> -#define AK09911_REG_HZH			0x16
> -
> -#define AK09911_REG_ASAX		0x60
> -#define AK09911_REG_ASAY		0x61
> -#define AK09911_REG_ASAZ		0x62
> -
> -#define AK09911_REG_CNTL1		0x30
> -#define AK09911_REG_CNTL2		0x31
> -#define AK09911_REG_CNTL3		0x32
> -
> -#define AK09911_MODE_SNG_MEASURE	0x01
> -#define AK09911_MODE_SELF_TEST		0x10
> -#define AK09911_MODE_FUSE_ACCESS	0x1F
> -#define AK09911_MODE_POWERDOWN		0x00
> -#define AK09911_RESET_DATA		0x01
> -
> -#define AK09911_REG_CNTL1		0x30
> -#define AK09911_REG_CNTL2		0x31
> -#define AK09911_REG_CNTL3		0x32
> -
> -#define AK09911_RAW_TO_GAUSS(asa)	((((asa) + 128) * 6000) / 256)
> -
> -#define AK09911_MAX_CONVERSION_TIMEOUT_MS	500
> -#define AK09911_CONVERSION_DONE_POLL_TIME_MS	10
> -
> -struct ak09911_data {
> -	struct i2c_client	*client;
> -	struct mutex		lock;
> -	u8			asa[3];
> -	long			raw_to_gauss[3];
> -};
> -
> -static const int ak09911_index_to_reg[] = {
> -	AK09911_REG_HXL, AK09911_REG_HYL, AK09911_REG_HZL,
> -};
> -
> -static int ak09911_set_mode(struct i2c_client *client, u8 mode)
> -{
> -	int ret;
> -
> -	switch (mode) {
> -	case AK09911_MODE_SNG_MEASURE:
> -	case AK09911_MODE_SELF_TEST:
> -	case AK09911_MODE_FUSE_ACCESS:
> -	case AK09911_MODE_POWERDOWN:
> -		ret = i2c_smbus_write_byte_data(client,
> -						AK09911_REG_CNTL2, mode);
> -		if (ret < 0) {
> -			dev_err(&client->dev, "set_mode error\n");
> -			return ret;
> -		}
> -		/* After mode change wait atleast 100us */
> -		usleep_range(100, 500);
> -		break;
> -	default:
> -		dev_err(&client->dev,
> -			"%s: Unknown mode(%d).", __func__, mode);
> -		return -EINVAL;
> -	}
> -
> -	return ret;
> -}
> -
> -/* Get Sensitivity Adjustment value */
> -static int ak09911_get_asa(struct i2c_client *client)
> -{
> -	struct iio_dev *indio_dev = i2c_get_clientdata(client);
> -	struct ak09911_data *data = iio_priv(indio_dev);
> -	int ret;
> -
> -	ret = ak09911_set_mode(client, AK09911_MODE_FUSE_ACCESS);
> -	if (ret < 0)
> -		return ret;
> -
> -	/* Get asa data and store in the device data. */
> -	ret = i2c_smbus_read_i2c_block_data(client, AK09911_REG_ASAX,
> -					    3, data->asa);
> -	if (ret < 0) {
> -		dev_err(&client->dev, "Not able to read asa data\n");
> -		return ret;
> -	}
> -
> -	ret = ak09911_set_mode(client,  AK09911_MODE_POWERDOWN);
> -	if (ret < 0)
> -		return ret;
> -
> -	data->raw_to_gauss[0] = AK09911_RAW_TO_GAUSS(data->asa[0]);
> -	data->raw_to_gauss[1] = AK09911_RAW_TO_GAUSS(data->asa[1]);
> -	data->raw_to_gauss[2] = AK09911_RAW_TO_GAUSS(data->asa[2]);
> -
> -	return 0;
> -}
> -
> -static int ak09911_verify_chip_id(struct i2c_client *client)
> -{
> -	u8 wia_val[2];
> -	int ret;
> -
> -	ret = i2c_smbus_read_i2c_block_data(client, AK09911_REG_WIA1,
> -					    2, wia_val);
> -	if (ret < 0) {
> -		dev_err(&client->dev, "Error reading WIA\n");
> -		return ret;
> -	}
> -
> -	dev_dbg(&client->dev, "WIA %02x %02x\n", wia_val[0], wia_val[1]);
> -
> -	if (wia_val[0] != AK09911_WIA1_VALUE ||
> -		wia_val[1] != AK09911_WIA2_VALUE) {
> -		dev_err(&client->dev, "Device ak09911 not found\n");
> -		return -ENODEV;
> -	}
> -
> -	return 0;
> -}
> -
> -static int wait_conversion_complete_polled(struct ak09911_data *data)
> -{
> -	struct i2c_client *client = data->client;
> -	u8 read_status;
> -	u32 timeout_ms = AK09911_MAX_CONVERSION_TIMEOUT_MS;
> -	int ret;
> -
> -	/* Wait for the conversion to complete. */
> -	while (timeout_ms) {
> -		msleep_interruptible(AK09911_CONVERSION_DONE_POLL_TIME_MS);
> -		ret = i2c_smbus_read_byte_data(client, AK09911_REG_ST1);
> -		if (ret < 0) {
> -			dev_err(&client->dev, "Error in reading ST1\n");
> -			return ret;
> -		}
> -		read_status = ret & 0x01;
> -		if (read_status)
> -			break;
> -		timeout_ms -= AK09911_CONVERSION_DONE_POLL_TIME_MS;
> -	}
> -	if (!timeout_ms) {
> -		dev_err(&client->dev, "Conversion timeout happened\n");
> -		return -EIO;
> -	}
> -
> -	return read_status;
> -}
> -
> -static int ak09911_read_axis(struct iio_dev *indio_dev, int index, int *val)
> -{
> -	struct ak09911_data *data = iio_priv(indio_dev);
> -	struct i2c_client *client = data->client;
> -	int ret;
> -
> -	mutex_lock(&data->lock);
> -
> -	ret = ak09911_set_mode(client, AK09911_MODE_SNG_MEASURE);
> -	if (ret < 0)
> -		goto fn_exit;
> -
> -	ret = wait_conversion_complete_polled(data);
> -	if (ret < 0)
> -		goto fn_exit;
> -
> -	/* Read data */
> -	ret = i2c_smbus_read_word_data(client, ak09911_index_to_reg[index]);
> -	if (ret < 0) {
> -		dev_err(&client->dev, "Read axis data fails\n");
> -		goto fn_exit;
> -	}
> -
> -	mutex_unlock(&data->lock);
> -
> -	/* Clamp to valid range. */
> -	*val = sign_extend32(clamp_t(s16, ret, -8192, 8191), 13);
> -
> -	return IIO_VAL_INT;
> -
> -fn_exit:
> -	mutex_unlock(&data->lock);
> -
> -	return ret;
> -}
> -
> -static int ak09911_read_raw(struct iio_dev *indio_dev,
> -			    struct iio_chan_spec const *chan,
> -			    int *val, int *val2,
> -			    long mask)
> -{
> -	struct ak09911_data *data = iio_priv(indio_dev);
> -
> -	switch (mask) {
> -	case IIO_CHAN_INFO_RAW:
> -		return ak09911_read_axis(indio_dev, chan->address, val);
> -	case IIO_CHAN_INFO_SCALE:
> -		*val = 0;
> -		*val2 = data->raw_to_gauss[chan->address];
> -		return IIO_VAL_INT_PLUS_MICRO;
> -	}
> -
> -	return -EINVAL;
> -}
> -
> -#define AK09911_CHANNEL(axis, index)					\
> -	{								\
> -		.type = IIO_MAGN,					\
> -		.modified = 1,						\
> -		.channel2 = IIO_MOD_##axis,				\
> -		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |		\
> -			     BIT(IIO_CHAN_INFO_SCALE),			\
> -		.address = index,					\
> -	}
> -
> -static const struct iio_chan_spec ak09911_channels[] = {
> -	AK09911_CHANNEL(X, 0), AK09911_CHANNEL(Y, 1), AK09911_CHANNEL(Z, 2),
> -};
> -
> -static const struct iio_info ak09911_info = {
> -	.read_raw = &ak09911_read_raw,
> -	.driver_module = THIS_MODULE,
> -};
> -
> -static const struct acpi_device_id ak_acpi_match[] = {
> -	{"AK009911", 0},
> -	{ },
> -};
> -MODULE_DEVICE_TABLE(acpi, ak_acpi_match);
> -
> -static int ak09911_probe(struct i2c_client *client,
> -			 const struct i2c_device_id *id)
> -{
> -	struct iio_dev *indio_dev;
> -	struct ak09911_data *data;
> -	const char *name;
> -	int ret;
> -
> -	ret = ak09911_verify_chip_id(client);
> -	if (ret) {
> -		dev_err(&client->dev, "AK00911 not detected\n");
> -		return -ENODEV;
> -	}
> -
> -	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
> -	if (indio_dev == NULL)
> -		return -ENOMEM;
> -
> -	data = iio_priv(indio_dev);
> -	i2c_set_clientdata(client, indio_dev);
> -
> -	data->client = client;
> -	mutex_init(&data->lock);
> -
> -	ret = ak09911_get_asa(client);
> -	if (ret)
> -		return ret;
> -
> -	if (id)
> -		name = id->name;
> -	else if (ACPI_HANDLE(&client->dev))
> -		name = dev_name(&client->dev);
> -	else
> -		return -ENODEV;
> -
> -	dev_dbg(&client->dev, "Asahi compass chip %s\n", name);
> -
> -	indio_dev->dev.parent = &client->dev;
> -	indio_dev->channels = ak09911_channels;
> -	indio_dev->num_channels = ARRAY_SIZE(ak09911_channels);
> -	indio_dev->info = &ak09911_info;
> -	indio_dev->modes = INDIO_DIRECT_MODE;
> -	indio_dev->name = name;
> -
> -	return devm_iio_device_register(&client->dev, indio_dev);
> -}
> -
> -static const struct i2c_device_id ak09911_id[] = {
> -	{"ak09911", 0},
> -	{}
> -};
> -
> -MODULE_DEVICE_TABLE(i2c, ak09911_id);
> -
> -static struct i2c_driver ak09911_driver = {
> -	.driver = {
> -		.name	= "ak09911",
> -		.acpi_match_table = ACPI_PTR(ak_acpi_match),
> -	},
> -	.probe		= ak09911_probe,
> -	.id_table	= ak09911_id,
> -};
> -module_i2c_driver(ak09911_driver);
> -
> -MODULE_AUTHOR("Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>");
> -MODULE_LICENSE("GPL v2");
> -MODULE_DESCRIPTION("AK09911 Compass driver");
> diff --git a/drivers/iio/magnetometer/ak8975.c b/drivers/iio/magnetometer/ak8975.c
> index 58c9a78..55d4732 100644
> --- a/drivers/iio/magnetometer/ak8975.c
> +++ b/drivers/iio/magnetometer/ak8975.c
> @@ -81,6 +81,58 @@
>  #define AK8975_MAX_REGS			AK8975_REG_ASAZ
>  
>  /*
> + * AK09912 Register definitions
> + */
> +#define AK09912_REG_WIA1		0x00
> +#define AK09912_REG_WIA2		0x01
> +#define AK09912_DEVICE_ID		0x04
> +#define AK09911_DEVICE_ID		0x05
> +
> +#define AK09911_REG_INFO1		0x02
> +#define AK09911_REG_INFO2		0x03
> +
> +#define AK09912_REG_ST1			0x10
> +
> +#define AK09912_REG_ST1_DRDY_SHIFT	0
> +#define AK09912_REG_ST1_DRDY_MASK	(1 << AK09912_REG_ST1_DRDY_SHIFT)
> +
> +#define AK09912_REG_HXL			0x11
> +#define AK09912_REG_HXH			0x12
> +#define AK09912_REG_HYL			0x13
> +#define AK09912_REG_HYH			0x14
> +#define AK09912_REG_HZL			0x15
> +#define AK09912_REG_HZH			0x16
> +#define AK09912_REG_TMPS		0x17
> +
> +#define AK09912_REG_ST2			0x18
> +#define AK09912_REG_ST2_HOFL_SHIFT	3
> +#define AK09912_REG_ST2_HOFL_MASK	(1 << AK09912_REG_ST2_HOFL_SHIFT)
> +
> +#define AK09912_REG_CNTL1		0x30
> +
> +#define AK09912_REG_CNTL2		0x31
> +#define AK09912_REG_CNTL_MODE_POWER_DOWN	0x00
> +#define AK09912_REG_CNTL_MODE_ONCE	0x01
> +#define AK09912_REG_CNTL_MODE_SELF_TEST	0x10
> +#define AK09912_REG_CNTL_MODE_FUSE_ROM	0x1F
> +#define AK09912_REG_CNTL2_MODE_SHIFT	0
> +#define AK09912_REG_CNTL2_MODE_MASK	(0x1F << AK09912_REG_CNTL2_MODE_SHIFT)
> +
> +#define AK09912_REG_CNTL3		0x32
> +
> +#define AK09912_REG_TS1			0x33
> +#define AK09912_REG_TS2			0x34
> +#define AK09912_REG_TS3			0x35
> +#define AK09912_REG_I2CDIS		0x36
> +#define AK09912_REG_TS4			0x37
> +
> +#define AK09912_REG_ASAX		0x60
> +#define AK09912_REG_ASAY		0x61
> +#define AK09912_REG_ASAZ		0x62
> +
> +#define AK09912_MAX_REGS		AK09912_REG_ASAZ
> +
> +/*
>   * Miscellaneous values.
>   */
>  #define AK8975_MAX_CONVERSION_TIMEOUT	500
> @@ -130,22 +182,37 @@ long ak8975_raw_to_gauss(u16 data)
>  }
>  
>  /*
> - * For AK8963, same calculation, but the device is less sensitive:
> + * For AK8963 and AK09911, same calculation, but the device is less sensitive:
>   *
>   * H is in the range of +-8190.  The magnetometer has a range of
>   * +-4912uT.  To go from the raw value to uT is:
>   *
>   * HuT = H * 4912/8190, or roughly, 6/10, instead of 3/10.
>   */
> -long ak8963_raw_to_gauss(u16 data)
> +long ak8963_09911_raw_to_gauss(u16 data)
>  {
>  	return (((long)data + 128) * 6000) / 256;
>  }
>  
> +/*
> + * For AK09912, same calculation, except the device is more sensitive:
> + *
> + * H is in the range of -32752 to 32752.  The magnetometer has a range of
> + * +-4912uT.  To go from the raw value to uT is:
> + *
> + * HuT = H * 4912/32752, or roughly, 3/20, instead of 3/10.
> + */
> +long ak09912_raw_to_gauss(u16 data)
> +{
> +	return (((long)data + 128) * 1500) / 256;
> +}
> +
>  /* Compatible Asahi Kasei Compass parts */
>  enum asahi_compass_chipset {
>  	AK8975,
>  	AK8963,
> +	AK09911,
> +	AK09912,
>  	AK_MAX_TYPE
>  };
>  
> @@ -210,7 +277,7 @@ struct ak_def {
>  	},
>  	{
>  		.type = AK8963,
> -		.raw_to_gauss = ak8963_raw_to_gauss,
> +		.raw_to_gauss = ak8963_09911_raw_to_gauss,
>  		.range = 8190,
>  		.ctrl_regs = {
>  			AK8975_REG_ST1,
> @@ -233,6 +300,56 @@ struct ak_def {
>  			AK8975_REG_HYL,
>  			AK8975_REG_HZL},
>  	},
> +	{
> +		.type = AK09911,
> +		.raw_to_gauss = ak8963_09911_raw_to_gauss,
> +		.range = 8192,
> +		.ctrl_regs = {
> +			AK09912_REG_ST1,
> +			AK09912_REG_ST2,
> +			AK09912_REG_CNTL2,
> +			AK09912_REG_ASAX,
> +			AK09912_MAX_REGS},
> +		.ctrl_masks = {
> +			AK09912_REG_ST1_DRDY_MASK,
> +			AK09912_REG_ST2_HOFL_MASK,
> +			0,
> +			AK09912_REG_CNTL2_MODE_MASK},
> +		.ctrl_modes = {
> +			AK09912_REG_CNTL_MODE_POWER_DOWN,
> +			AK09912_REG_CNTL_MODE_ONCE,
> +			AK09912_REG_CNTL_MODE_SELF_TEST,
> +			AK09912_REG_CNTL_MODE_FUSE_ROM},
> +		.data_regs = {
> +			AK09912_REG_HXL,
> +			AK09912_REG_HYL,
> +			AK09912_REG_HZL},
> +	},
> +	{
> +		.type = AK09912,
> +		.raw_to_gauss = ak09912_raw_to_gauss,
> +		.range = 32752,
> +		.ctrl_regs = {
> +			AK09912_REG_ST1,
> +			AK09912_REG_ST2,
> +			AK09912_REG_CNTL2,
> +			AK09912_REG_ASAX,
> +			AK09912_MAX_REGS},
> +		.ctrl_masks = {
> +			AK09912_REG_ST1_DRDY_MASK,
> +			AK09912_REG_ST2_HOFL_MASK,
> +			0,
> +			AK09912_REG_CNTL2_MODE_MASK},
> +		.ctrl_modes = {
> +			AK09912_REG_CNTL_MODE_POWER_DOWN,
> +			AK09912_REG_CNTL_MODE_ONCE,
> +			AK09912_REG_CNTL_MODE_SELF_TEST,
> +			AK09912_REG_CNTL_MODE_FUSE_ROM},
> +		.data_regs = {
> +			AK09912_REG_HXL,
> +			AK09912_REG_HYL,
> +			AK09912_REG_HZL},
> +	}
>  };
>  
>  /*
> @@ -253,6 +370,52 @@ struct ak8975_data {
>  };
>  
>  /*
> + * Return 0 if the i2c device is the one we expect.
> + * return a negative error number otherwise
> + */
> +static int ak8975_who_i_am(struct i2c_client *client,
> +			   enum asahi_compass_chipset type)
> +{
> +	u8 wia_val[2];
> +	int ret;
> +
> +	/*
> +	 * Signature for each device:
> +	 * Device   |  WIA1      |  WIA2
> +	 * AK09912  |  DEVICE_ID |  AK09912_DEVICE_ID
> +	 * AK09911  |  DEVICE_ID |  AK09911_DEVICE_ID
> +	 * AK8975   |  DEVICE_ID |  NA
> +	 * AK8963   |  DEVICE_ID |  NA
> +	 */
> +	ret = i2c_smbus_read_i2c_block_data(client, AK09912_REG_WIA1,
> +					    2, wia_val);
> +	if (ret < 0) {
> +		dev_err(&client->dev, "Error reading WIA\n");
> +		return ret;
> +	}
> +
> +	if (wia_val[0] != AK8975_DEVICE_ID)
> +		return -ENODEV;
> +
> +	switch (type) {
> +	case AK8975:
> +	case AK8963:
> +		return 0;
> +	case AK09911:
> +		if (wia_val[1] == AK09911_DEVICE_ID)
> +			return 0;
> +		break;
> +	case AK09912:
> +		if (wia_val[1] == AK09912_DEVICE_ID)
> +			return 0;
> +		break;
> +	default:
> +		dev_err(&client->dev, "Type %d unknown\n", type);
> +	}
> +	return -ENODEV;
> +}
> +
> +/*
>   * Helper function to write to CNTL register.
>   */
>  static int ak8975_set_mode(struct ak8975_data *data, enum ak_ctrl_mode mode)
> @@ -327,21 +490,8 @@ static int ak8975_setup(struct i2c_client *client)
>  {
>  	struct iio_dev *indio_dev = i2c_get_clientdata(client);
>  	struct ak8975_data *data = iio_priv(indio_dev);
> -	u8 device_id;
>  	int ret;
>  
> -	/* Confirm that the device we're talking to is really an AK8975. */
> -	ret = i2c_smbus_read_byte_data(client, AK8975_REG_WIA);
> -	if (ret < 0) {
> -		dev_err(&client->dev, "Error reading WIA\n");
> -		return ret;
> -	}
> -	device_id = ret;
> -	if (device_id != AK8975_DEVICE_ID) {
> -		dev_err(&client->dev, "Device ak8975 not found\n");
> -		return -ENODEV;
> -	}
> -
>  	/* Write the fused rom access mode. */
>  	ret = ak8975_set_mode(data, FUSE_ROM);
>  	if (ret < 0) {
> @@ -552,6 +702,8 @@ static const struct acpi_device_id ak_acpi_match[] = {
>  	{"AK8975", AK8975},
>  	{"AK8963", AK8963},
>  	{"INVN6500", AK8963},
> +	{"AK09911", AK09911},
> +	{"AK09912", AK09912},
>  	{ },
>  };
>  MODULE_DEVICE_TABLE(acpi, ak_acpi_match);
> @@ -631,6 +783,11 @@ static int ak8975_probe(struct i2c_client *client,
>  	}
>  
>  	data->def = &ak_def_array[chipset];
> +	err = ak8975_who_i_am(client, data->def->type);
> +	if (err < 0) {
> +		dev_err(&client->dev, "Unexpected device\n");
> +		return err;
> +	}
>  	dev_dbg(&client->dev, "Asahi compass chip %s\n", name);
>  
>  	/* Perform some basic start-of-day setup of the device. */
> @@ -653,6 +810,8 @@ static int ak8975_probe(struct i2c_client *client,
>  static const struct i2c_device_id ak8975_id[] = {
>  	{"ak8975", AK8975},
>  	{"ak8963", AK8963},
> +	{"ak09911", AK09911},
> +	{"ak09912", AK09912},
>  	{}
>  };
>  
> @@ -663,6 +822,10 @@ static const struct of_device_id ak8975_of_match[] = {
>  	{ .compatible = "ak8975", },
>  	{ .compatible = "asahi-kasei,ak8963", },
>  	{ .compatible = "ak8963", },
> +	{ .compatible = "asahi-kasei,ak09911", },
> +	{ .compatible = "ak09911", },
> +	{ .compatible = "asahi-kasei,ak09912", },
> +	{ .compatible = "ak09912", },
>  	{}
>  };
>  MODULE_DEVICE_TABLE(of, ak8975_of_match);
>