* [PATCH v9 0/5] iio: magnetometer: ak8975: driver cleanup
@ 2026-09-20 18:05 Joshua Crofts
2026-09-20 18:05 ` [PATCH v9 1/5] iio: magnetometer: ak8975: switch to using managed resources Joshua Crofts
` (4 more replies)
0 siblings, 5 replies; 6+ messages in thread
From: Joshua Crofts @ 2026-09-20 18:05 UTC (permalink / raw)
To: Jonathan Cameron, David Lechner, Nuno Sá, Andy Shevchenko
Cc: linux-iio, linux-kernel, Joshua Crofts, Andy Shevchenko
This is a 4-month old series that I had in my working tree and
completely forgot about. It's a continuation of the ak8975 driver
cleanup that Andy and I worked on, all that was missing was to
implement Jonathan's powered_on bool idea. The rest of the patches
have Reviewed-by tags.
Very sorry for the long delay :(
Original cover letter contents:
This series is a continuation of the previous ak8975 driver cleanup
effort, as most of the patches were picked.
Changes include:
- using BIT() and GENMASK() macros
- moving to devm_* resource management
- adding a scan index enum
- moving from using wait loops to iopoll functions
- various code style changes
Signed-off-by: Joshua Crofts <joshua.crofts1@gmail.com>
---
Changes in v9:
- Add powered_on bool per Jonathan's review
- Move forgotten dev_err() call to use a local dev variable
- Link to v8: https://lore.kernel.org/all/20260518-magnetometer-fixes-post-pickup-v8-0-088d610108a0@gmail.com/
---
Andy Shevchenko (4):
iio: magnetometer: ak8975: switch to using managed resources
iio: magnetometer: ak8975: unify messages with help of dev_err_probe()
iio: magnetometer: ak8975: use temporary variable for struct device
iio: magnetometer: ak8975: make use of the macros from bits.h
Joshua Crofts (1):
iio: magnetometer: ak8975: add scan mask index enum
drivers/iio/magnetometer/ak8975.c | 213 +++++++++++++++++++-------------------
1 file changed, 107 insertions(+), 106 deletions(-)
---
base-commit: 40288c9206c17eb66a603262e06a58d300d0f279
change-id: 20260919-ak8975-cleanup-206e303af804
Best regards,
--
Kind regards,
Joshua Crofts
^ permalink raw reply [flat|nested] 6+ messages in thread
* [PATCH v9 1/5] iio: magnetometer: ak8975: switch to using managed resources
2026-09-20 18:05 [PATCH v9 0/5] iio: magnetometer: ak8975: driver cleanup Joshua Crofts
@ 2026-09-20 18:05 ` Joshua Crofts
2026-09-20 18:05 ` [PATCH v9 2/5] iio: magnetometer: ak8975: unify messages with help of dev_err_probe() Joshua Crofts
` (3 subsequent siblings)
4 siblings, 0 replies; 6+ messages in thread
From: Joshua Crofts @ 2026-09-20 18:05 UTC (permalink / raw)
To: Jonathan Cameron, David Lechner, Nuno Sá, Andy Shevchenko
Cc: linux-iio, linux-kernel, Joshua Crofts, Andy Shevchenko
From: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Switch the driver to use managed resources (devm_*) which simplifier
error handling and allows removing ak8975_remove() method from
the driver.
Note, on error path we now also set mode to POWER_DOWN state which is
fine. Even if the device is in that mode, there is no problem to set
that mode again, it should be no-op.
Additionally, remove any pm_runtime_get/put*() function calls that
dummy cycled the counter to autosuspend the device.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Co-developed-by: Joshua Crofts <joshua.crofts1@gmail.com>
Signed-off-by: Joshua Crofts <joshua.crofts1@gmail.com>
---
drivers/iio/magnetometer/ak8975.c | 80 +++++++++++++++++++++------------------
1 file changed, 44 insertions(+), 36 deletions(-)
diff --git a/drivers/iio/magnetometer/ak8975.c b/drivers/iio/magnetometer/ak8975.c
index 8b0c07f82602..d217fdf34bce 100644
--- a/drivers/iio/magnetometer/ak8975.c
+++ b/drivers/iio/magnetometer/ak8975.c
@@ -418,6 +418,7 @@ struct ak8975_data {
wait_queue_head_t data_ready_queue;
unsigned long flags;
u8 cntl_cache;
+ bool powered_on;
struct iio_mount_matrix orientation;
struct regulator *vdd;
struct regulator *vid;
@@ -430,7 +431,7 @@ struct ak8975_data {
};
/* Enable attached power regulator if any. */
-static int ak8975_power_on(const struct ak8975_data *data)
+static int ak8975_power_on(struct ak8975_data *data)
{
int ret;
@@ -457,16 +458,22 @@ static int ak8975_power_on(const struct ak8975_data *data)
*/
fsleep(500);
+ data->powered_on = true;
return 0;
}
/* Disable attached power regulator if any. */
-static void ak8975_power_off(const struct ak8975_data *data)
+static void ak8975_power_off(struct ak8975_data *data)
{
+ if (!data->powered_on)
+ return;
+
gpiod_set_value_cansleep(data->reset_gpiod, 1);
regulator_disable(data->vid);
regulator_disable(data->vdd);
+
+ data->powered_on = false;
}
/*
@@ -934,9 +941,23 @@ static const struct iio_buffer_setup_ops ak8975_buffer_setup_ops = {
.preenable = ak8975_buffer_preenable,
.postdisable = ak8975_buffer_postdisable,
};
+
+static void devm_ak8975_power_off(void *data)
+{
+ struct ak8975_data *ak = data;
+
+ if (!ak->powered_on)
+ return;
+
+ /* Soft-stop the chip before hard-stopping the regulators */
+ ak8975_set_mode(data, POWER_DOWN);
+ ak8975_power_off(data);
+}
+
static int ak8975_probe(struct i2c_client *client)
{
const struct i2c_device_id *id = i2c_client_get_device_id(client);
+ struct device *dev = &client->dev;
struct ak8975_data *data;
struct iio_dev *indio_dev;
struct gpio_desc *eoc_gpiod;
@@ -1004,10 +1025,14 @@ static int ak8975_probe(struct i2c_client *client)
if (ret)
return ret;
+ ret = devm_add_action_or_reset(dev, devm_ak8975_power_off, data);
+ if (ret)
+ return ret;
+
ret = ak8975_who_i_am(data, data->def->type);
if (ret) {
dev_err(&client->dev, "Unexpected device\n");
- goto power_off;
+ return ret;
}
dev_dbg(&client->dev, "Asahi compass chip %s\n", name);
@@ -1015,10 +1040,13 @@ static int ak8975_probe(struct i2c_client *client)
ret = ak8975_setup(data);
if (ret) {
dev_err(&client->dev, "%s initialization fails\n", name);
- goto power_off;
+ return ret;
}
- mutex_init(&data->lock);
+ ret = devm_mutex_init(dev, &data->lock);
+ if (ret)
+ return ret;
+
indio_dev->channels = ak8975_channels;
indio_dev->num_channels = ARRAY_SIZE(ak8975_channels);
indio_dev->info = &ak8975_info;
@@ -1026,52 +1054,33 @@ static int ak8975_probe(struct i2c_client *client)
indio_dev->modes = INDIO_DIRECT_MODE;
indio_dev->name = name;
- ret = iio_triggered_buffer_setup(indio_dev, NULL, ak8975_handle_trigger,
- &ak8975_buffer_setup_ops);
+ ret = devm_iio_triggered_buffer_setup(dev, indio_dev, NULL,
+ ak8975_handle_trigger,
+ &ak8975_buffer_setup_ops);
if (ret) {
dev_err(&client->dev, "triggered buffer setup failed\n");
- goto power_off;
+ return ret;
}
- ret = iio_device_register(indio_dev);
+ pm_runtime_set_active(dev);
+ ret = devm_pm_runtime_enable(dev);
+ if (ret)
+ return ret;
+
+ ret = devm_iio_device_register(dev, indio_dev);
if (ret) {
dev_err(&client->dev, "device register failed\n");
- goto cleanup_buffer;
+ return ret;
}
- /* Enable runtime PM */
- pm_runtime_get_noresume(&client->dev);
- pm_runtime_set_active(&client->dev);
- pm_runtime_enable(&client->dev);
/*
* The device comes online in 500us, so add two orders of magnitude
* of delay before autosuspending: 50 ms.
*/
pm_runtime_set_autosuspend_delay(&client->dev, 50);
pm_runtime_use_autosuspend(&client->dev);
- pm_runtime_put(&client->dev);
return 0;
-
-cleanup_buffer:
- iio_triggered_buffer_cleanup(indio_dev);
-power_off:
- ak8975_power_off(data);
- return ret;
-}
-
-static void ak8975_remove(struct i2c_client *client)
-{
- struct iio_dev *indio_dev = i2c_get_clientdata(client);
- struct ak8975_data *data = iio_priv(indio_dev);
-
- pm_runtime_get_sync(&client->dev);
- pm_runtime_put_noidle(&client->dev);
- pm_runtime_disable(&client->dev);
- iio_device_unregister(indio_dev);
- iio_triggered_buffer_cleanup(indio_dev);
- ak8975_set_mode(data, POWER_DOWN);
- ak8975_power_off(data);
}
static int ak8975_runtime_suspend(struct device *dev)
@@ -1165,7 +1174,6 @@ static struct i2c_driver ak8975_driver = {
.acpi_match_table = ak_acpi_match,
},
.probe = ak8975_probe,
- .remove = ak8975_remove,
.id_table = ak8975_id,
};
module_i2c_driver(ak8975_driver);
--
2.55.0
^ permalink raw reply [flat|nested] 6+ messages in thread
* [PATCH v9 2/5] iio: magnetometer: ak8975: unify messages with help of dev_err_probe()
2026-09-20 18:05 [PATCH v9 0/5] iio: magnetometer: ak8975: driver cleanup Joshua Crofts
2026-09-20 18:05 ` [PATCH v9 1/5] iio: magnetometer: ak8975: switch to using managed resources Joshua Crofts
@ 2026-09-20 18:05 ` Joshua Crofts
2026-09-20 18:05 ` [PATCH v9 3/5] iio: magnetometer: ak8975: use temporary variable for struct device Joshua Crofts
` (2 subsequent siblings)
4 siblings, 0 replies; 6+ messages in thread
From: Joshua Crofts @ 2026-09-20 18:05 UTC (permalink / raw)
To: Jonathan Cameron, David Lechner, Nuno Sá, Andy Shevchenko
Cc: linux-iio, linux-kernel, Joshua Crofts, Andy Shevchenko
From: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Unify error messages that might appear during probe phase by
switching to use dev_err_probe().
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Nuno Sá <nuno.sa@analog.com>
Signed-off-by: Joshua Crofts <joshua.crofts1@gmail.com>
---
drivers/iio/magnetometer/ak8975.c | 37 +++++++++++++------------------------
1 file changed, 13 insertions(+), 24 deletions(-)
diff --git a/drivers/iio/magnetometer/ak8975.c b/drivers/iio/magnetometer/ak8975.c
index d217fdf34bce..59a7bb83a731 100644
--- a/drivers/iio/magnetometer/ak8975.c
+++ b/drivers/iio/magnetometer/ak8975.c
@@ -501,14 +501,10 @@ static int ak8975_who_i_am(const struct ak8975_data *data,
AK09912_REG_WIA1,
sizeof(wia_val),
wia_val);
- if (ret < 0) {
- dev_err(&client->dev, "Error reading WIA\n");
- return ret;
- }
- if (ret != sizeof(wia_val)) {
- dev_err(&client->dev, "Error reading WIA\n");
- return -EIO;
- }
+ if (ret < 0)
+ return dev_err_probe(&client->dev, ret, "Error reading WIA\n");
+ if (ret != sizeof(wia_val))
+ return dev_err_probe(&client->dev, -EIO, "Error reading WIA\n");
if (wia_val[0] != AK8975_DEVICE_ID)
return -ENODEV;
@@ -1030,18 +1026,15 @@ static int ak8975_probe(struct i2c_client *client)
return ret;
ret = ak8975_who_i_am(data, data->def->type);
- if (ret) {
- dev_err(&client->dev, "Unexpected device\n");
- return ret;
- }
+ if (ret)
+ return dev_err_probe(dev, ret, "Unexpected device\n");
+
dev_dbg(&client->dev, "Asahi compass chip %s\n", name);
/* Perform some basic start-of-day setup of the device. */
ret = ak8975_setup(data);
- if (ret) {
- dev_err(&client->dev, "%s initialization fails\n", name);
- return ret;
- }
+ if (ret)
+ return dev_err_probe(dev, ret, "%s initialization fails\n", name);
ret = devm_mutex_init(dev, &data->lock);
if (ret)
@@ -1057,10 +1050,8 @@ static int ak8975_probe(struct i2c_client *client)
ret = devm_iio_triggered_buffer_setup(dev, indio_dev, NULL,
ak8975_handle_trigger,
&ak8975_buffer_setup_ops);
- if (ret) {
- dev_err(&client->dev, "triggered buffer setup failed\n");
- return ret;
- }
+ if (ret)
+ return dev_err_probe(dev, ret, "triggered buffer setup failed\n");
pm_runtime_set_active(dev);
ret = devm_pm_runtime_enable(dev);
@@ -1068,10 +1059,8 @@ static int ak8975_probe(struct i2c_client *client)
return ret;
ret = devm_iio_device_register(dev, indio_dev);
- if (ret) {
- dev_err(&client->dev, "device register failed\n");
- return ret;
- }
+ if (ret)
+ return dev_err_probe(dev, ret, "device register failed\n");
/*
* The device comes online in 500us, so add two orders of magnitude
--
2.55.0
^ permalink raw reply [flat|nested] 6+ messages in thread
* [PATCH v9 3/5] iio: magnetometer: ak8975: use temporary variable for struct device
2026-09-20 18:05 [PATCH v9 0/5] iio: magnetometer: ak8975: driver cleanup Joshua Crofts
2026-09-20 18:05 ` [PATCH v9 1/5] iio: magnetometer: ak8975: switch to using managed resources Joshua Crofts
2026-09-20 18:05 ` [PATCH v9 2/5] iio: magnetometer: ak8975: unify messages with help of dev_err_probe() Joshua Crofts
@ 2026-09-20 18:05 ` Joshua Crofts
2026-09-20 18:05 ` [PATCH v9 4/5] iio: magnetometer: ak8975: add scan mask index enum Joshua Crofts
2026-09-20 18:05 ` [PATCH v9 5/5] iio: magnetometer: ak8975: make use of the macros from bits.h Joshua Crofts
4 siblings, 0 replies; 6+ messages in thread
From: Joshua Crofts @ 2026-09-20 18:05 UTC (permalink / raw)
To: Jonathan Cameron, David Lechner, Nuno Sá, Andy Shevchenko
Cc: linux-iio, linux-kernel, Joshua Crofts, Andy Shevchenko
From: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Use temporary variable for struct device to make code neater.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Nuno Sá <nuno.sa@analog.com>
Signed-off-by: Joshua Crofts <joshua.crofts1@gmail.com>
---
drivers/iio/magnetometer/ak8975.c | 65 +++++++++++++++++++--------------------
1 file changed, 32 insertions(+), 33 deletions(-)
diff --git a/drivers/iio/magnetometer/ak8975.c b/drivers/iio/magnetometer/ak8975.c
index 59a7bb83a731..42f6892f4efd 100644
--- a/drivers/iio/magnetometer/ak8975.c
+++ b/drivers/iio/magnetometer/ak8975.c
@@ -433,18 +433,17 @@ struct ak8975_data {
/* Enable attached power regulator if any. */
static int ak8975_power_on(struct ak8975_data *data)
{
+ struct device *dev = &data->client->dev;
int ret;
ret = regulator_enable(data->vdd);
if (ret) {
- dev_warn(&data->client->dev,
- "Failed to enable specified Vdd supply\n");
+ dev_warn(dev, "Failed to enable specified Vdd supply\n");
return ret;
}
ret = regulator_enable(data->vid);
if (ret) {
- dev_warn(&data->client->dev,
- "Failed to enable specified Vid supply\n");
+ dev_warn(dev, "Failed to enable specified Vid supply\n");
regulator_disable(data->vdd);
return ret;
}
@@ -580,6 +579,7 @@ static irqreturn_t ak8975_irq_handler(int irq, void *data)
static int ak8975_setup_irq(struct ak8975_data *data)
{
struct i2c_client *client = data->client;
+ struct device *dev = &client->dev;
int irq;
int ret;
@@ -590,9 +590,8 @@ static int ak8975_setup_irq(struct ak8975_data *data)
else
irq = gpiod_to_irq(data->eoc_gpiod);
- ret = devm_request_irq(&client->dev, irq, ak8975_irq_handler,
- IRQF_TRIGGER_RISING,
- dev_name(&client->dev), data);
+ ret = devm_request_irq(dev, irq, ak8975_irq_handler, IRQF_TRIGGER_RISING,
+ dev_name(dev), data);
if (ret)
return ret;
@@ -608,12 +607,13 @@ static int ak8975_setup_irq(struct ak8975_data *data)
static int ak8975_setup(struct ak8975_data *data)
{
struct i2c_client *client = data->client;
+ struct device *dev = &client->dev;
int ret;
/* Write the fused rom access mode. */
ret = ak8975_set_mode(data, FUSE_ROM);
if (ret < 0) {
- dev_err(&client->dev, "Error in setting fuse access mode\n");
+ dev_err(dev, "Error in setting fuse access mode\n");
return ret;
}
@@ -623,26 +623,25 @@ static int ak8975_setup(struct ak8975_data *data)
sizeof(data->asa),
data->asa);
if (ret < 0) {
- dev_err(&client->dev, "Not able to read asa data\n");
+ dev_err(dev, "Not able to read asa data\n");
return ret;
}
if (ret != sizeof(data->asa)) {
- dev_err(&client->dev, "Error reading asa data\n");
+ dev_err(dev, "Error reading asa data\n");
return -EIO;
}
/* After reading fuse ROM data set power-down mode */
ret = ak8975_set_mode(data, POWER_DOWN);
if (ret < 0) {
- dev_err(&client->dev, "Error in setting power-down mode\n");
+ dev_err(dev, "Error in setting power-down mode\n");
return ret;
}
if (data->eoc_gpiod || client->irq > 0) {
ret = ak8975_setup_irq(data);
if (ret < 0) {
- dev_err(&client->dev,
- "Error setting data ready interrupt\n");
+ dev_err(dev, "Error setting data ready interrupt\n");
return ret;
}
}
@@ -748,10 +747,11 @@ static int ak8975_read_axis(struct iio_dev *indio_dev, int index, int *val)
struct ak8975_data *data = iio_priv(indio_dev);
const struct i2c_client *client = data->client;
const struct ak_def *def = data->def;
+ struct device *dev = &data->client->dev;
__le16 rval;
int ret;
- pm_runtime_get_sync(&data->client->dev);
+ pm_runtime_get_sync(dev);
mutex_lock(&data->lock);
@@ -773,20 +773,20 @@ static int ak8975_read_axis(struct iio_dev *indio_dev, int index, int *val)
/* Read out ST2 for release lock on measurement data. */
ret = i2c_smbus_read_byte_data(client, data->def->ctrl_regs[ST2]);
if (ret < 0) {
- dev_err(&client->dev, "Error in reading ST2\n");
+ dev_err(dev, "Error in reading ST2\n");
goto exit;
}
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);
+ dev_err(dev, "ST2 status error 0x%x\n", ret);
ret = -EINVAL;
goto exit;
}
mutex_unlock(&data->lock);
- pm_runtime_put_autosuspend(&data->client->dev);
+ pm_runtime_put_autosuspend(dev);
/* Swap bytes and convert to valid range. */
*val = clamp_t(s16, le16_to_cpu(rval), -def->range, def->range);
@@ -795,8 +795,8 @@ static int ak8975_read_axis(struct iio_dev *indio_dev, int index, int *val)
exit:
mutex_unlock(&data->lock);
- pm_runtime_put_autosuspend(&data->client->dev);
- dev_err(&client->dev, "Error in reading axis\n");
+ pm_runtime_put_autosuspend(dev);
+ dev_err(dev, "Error in reading axis\n");
return ret;
}
@@ -966,7 +966,7 @@ static int ak8975_probe(struct i2c_client *client)
* We may not have a GPIO based IRQ to scan, that is fine, we will
* poll if so.
*/
- eoc_gpiod = devm_gpiod_get_optional(&client->dev, NULL, GPIOD_IN);
+ eoc_gpiod = devm_gpiod_get_optional(dev, NULL, GPIOD_IN);
if (IS_ERR(eoc_gpiod))
return PTR_ERR(eoc_gpiod);
gpiod_set_consumer_name(eoc_gpiod, "ak_8975");
@@ -976,13 +976,12 @@ static int ak8975_probe(struct i2c_client *client)
* deassert reset on ak8975_power_on() and assert reset on
* ak8975_power_off().
*/
- reset_gpiod = devm_gpiod_get_optional(&client->dev,
- "reset", GPIOD_OUT_HIGH);
+ reset_gpiod = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_HIGH);
if (IS_ERR(reset_gpiod))
return PTR_ERR(reset_gpiod);
/* Register with IIO */
- indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
+ indio_dev = devm_iio_device_alloc(dev, sizeof(*data));
if (indio_dev == NULL)
return -ENOMEM;
@@ -994,7 +993,7 @@ static int ak8975_probe(struct i2c_client *client)
data->reset_gpiod = reset_gpiod;
data->eoc_irq = 0;
- ret = iio_read_mount_matrix(&client->dev, &data->orientation);
+ ret = iio_read_mount_matrix(dev, &data->orientation);
if (ret)
return ret;
@@ -1004,16 +1003,16 @@ static int ak8975_probe(struct i2c_client *client)
return -ENODEV;
/* If enumerated via firmware node, fix the ABI */
- if (dev_fwnode(&client->dev))
- name = dev_name(&client->dev);
+ if (dev_fwnode(dev))
+ name = dev_name(dev);
else
name = id->name;
/* Fetch the regulators */
- data->vdd = devm_regulator_get(&client->dev, "vdd");
+ data->vdd = devm_regulator_get(dev, "vdd");
if (IS_ERR(data->vdd))
return PTR_ERR(data->vdd);
- data->vid = devm_regulator_get(&client->dev, "vid");
+ data->vid = devm_regulator_get(dev, "vid");
if (IS_ERR(data->vid))
return PTR_ERR(data->vid);
@@ -1029,7 +1028,7 @@ static int ak8975_probe(struct i2c_client *client)
if (ret)
return dev_err_probe(dev, ret, "Unexpected device\n");
- dev_dbg(&client->dev, "Asahi compass chip %s\n", name);
+ dev_dbg(dev, "Asahi compass chip %s\n", name);
/* Perform some basic start-of-day setup of the device. */
ret = ak8975_setup(data);
@@ -1066,8 +1065,8 @@ static int ak8975_probe(struct i2c_client *client)
* The device comes online in 500us, so add two orders of magnitude
* of delay before autosuspending: 50 ms.
*/
- pm_runtime_set_autosuspend_delay(&client->dev, 50);
- pm_runtime_use_autosuspend(&client->dev);
+ pm_runtime_set_autosuspend_delay(dev, 50);
+ pm_runtime_use_autosuspend(dev);
return 0;
}
@@ -1082,7 +1081,7 @@ static int ak8975_runtime_suspend(struct device *dev)
/* Set the device in power down if it wasn't already */
ret = ak8975_set_mode(data, POWER_DOWN);
if (ret < 0) {
- dev_err(&client->dev, "Error in setting power-down mode\n");
+ dev_err(dev, "Error in setting power-down mode\n");
return ret;
}
/* Next cut the regulators */
@@ -1106,7 +1105,7 @@ static int ak8975_runtime_resume(struct device *dev)
*/
ret = ak8975_set_mode(data, POWER_DOWN);
if (ret < 0) {
- dev_err(&client->dev, "Error in setting power-down mode\n");
+ dev_err(dev, "Error in setting power-down mode\n");
return ret;
}
--
2.55.0
^ permalink raw reply [flat|nested] 6+ messages in thread
* [PATCH v9 4/5] iio: magnetometer: ak8975: add scan mask index enum
2026-09-20 18:05 [PATCH v9 0/5] iio: magnetometer: ak8975: driver cleanup Joshua Crofts
` (2 preceding siblings ...)
2026-09-20 18:05 ` [PATCH v9 3/5] iio: magnetometer: ak8975: use temporary variable for struct device Joshua Crofts
@ 2026-09-20 18:05 ` Joshua Crofts
2026-09-20 18:05 ` [PATCH v9 5/5] iio: magnetometer: ak8975: make use of the macros from bits.h Joshua Crofts
4 siblings, 0 replies; 6+ messages in thread
From: Joshua Crofts @ 2026-09-20 18:05 UTC (permalink / raw)
To: Jonathan Cameron, David Lechner, Nuno Sá, Andy Shevchenko
Cc: linux-iio, linux-kernel, Joshua Crofts
Add an enum to explicitly define scan mask indexes for the X, Y, Z and
timestamp channels. Also, update the struct iio_chan_spec to use said
enum for the .scan_index parameter.
This prevents magic numbers from obscuring the hardware channel mapping
and improves code style.
No functional change.
Suggested-by: Jonathan Cameron <jic23@kernel.org>
Reviewed-by: Nuno Sá <nuno.sa@analog.com>
Signed-off-by: Joshua Crofts <joshua.crofts1@gmail.com>
---
drivers/iio/magnetometer/ak8975.c | 13 +++++++++++--
1 file changed, 11 insertions(+), 2 deletions(-)
diff --git a/drivers/iio/magnetometer/ak8975.c b/drivers/iio/magnetometer/ak8975.c
index 42f6892f4efd..ac556644b02d 100644
--- a/drivers/iio/magnetometer/ak8975.c
+++ b/drivers/iio/magnetometer/ak8975.c
@@ -237,6 +237,13 @@ enum ak_ctrl_mode {
MODE_END,
};
+enum ak_chan_index {
+ AK8975_CHAN_X,
+ AK8975_CHAN_Y,
+ AK8975_CHAN_Z,
+ AK8975_CHAN_TS,
+};
+
struct ak_def {
enum asahi_compass_chipset type;
long (*raw_to_gauss)(u16 data);
@@ -851,8 +858,10 @@ static const struct iio_chan_spec_ext_info ak8975_ext_info[] = {
}
static const struct iio_chan_spec ak8975_channels[] = {
- AK8975_CHANNEL(X, 0), AK8975_CHANNEL(Y, 1), AK8975_CHANNEL(Z, 2),
- IIO_CHAN_SOFT_TIMESTAMP(3),
+ AK8975_CHANNEL(X, AK8975_CHAN_X),
+ AK8975_CHANNEL(Y, AK8975_CHAN_Y),
+ AK8975_CHANNEL(Z, AK8975_CHAN_Z),
+ IIO_CHAN_SOFT_TIMESTAMP(AK8975_CHAN_TS),
};
static const unsigned long ak8975_scan_masks[] = { 0x7, 0 };
--
2.55.0
^ permalink raw reply [flat|nested] 6+ messages in thread
* [PATCH v9 5/5] iio: magnetometer: ak8975: make use of the macros from bits.h
2026-09-20 18:05 [PATCH v9 0/5] iio: magnetometer: ak8975: driver cleanup Joshua Crofts
` (3 preceding siblings ...)
2026-09-20 18:05 ` [PATCH v9 4/5] iio: magnetometer: ak8975: add scan mask index enum Joshua Crofts
@ 2026-09-20 18:05 ` Joshua Crofts
4 siblings, 0 replies; 6+ messages in thread
From: Joshua Crofts @ 2026-09-20 18:05 UTC (permalink / raw)
To: Jonathan Cameron, David Lechner, Nuno Sá, Andy Shevchenko
Cc: linux-iio, linux-kernel, Joshua Crofts, Andy Shevchenko
From: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Make use of BIT() and GENMASK() where it makes sense.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Nuno Sá <nuno.sa@analog.com>
Co-developed-by: Joshua Crofts <joshua.crofts1@gmail.com>
Signed-off-by: Joshua Crofts <joshua.crofts1@gmail.com>
---
drivers/iio/magnetometer/ak8975.c | 26 +++++++++++---------------
1 file changed, 11 insertions(+), 15 deletions(-)
diff --git a/drivers/iio/magnetometer/ak8975.c b/drivers/iio/magnetometer/ak8975.c
index ac556644b02d..05cdd285c5f4 100644
--- a/drivers/iio/magnetometer/ak8975.c
+++ b/drivers/iio/magnetometer/ak8975.c
@@ -44,8 +44,7 @@
#define AK8975_REG_INFO 0x01
#define AK8975_REG_ST1 0x02
-#define AK8975_REG_ST1_DRDY_SHIFT 0
-#define AK8975_REG_ST1_DRDY_MASK (1 << AK8975_REG_ST1_DRDY_SHIFT)
+#define AK8975_REG_ST1_DRDY_MASK BIT(0)
#define AK8975_REG_HXL 0x03
#define AK8975_REG_HXH 0x04
@@ -54,15 +53,12 @@
#define AK8975_REG_HZL 0x07
#define AK8975_REG_HZH 0x08
#define AK8975_REG_ST2 0x09
-#define AK8975_REG_ST2_DERR_SHIFT 2
-#define AK8975_REG_ST2_DERR_MASK (1 << AK8975_REG_ST2_DERR_SHIFT)
+#define AK8975_REG_ST2_DERR_MASK BIT(2)
-#define AK8975_REG_ST2_HOFL_SHIFT 3
-#define AK8975_REG_ST2_HOFL_MASK (1 << AK8975_REG_ST2_HOFL_SHIFT)
+#define AK8975_REG_ST2_HOFL_MASK BIT(3)
#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_MASK GENMASK(3, 0)
#define AK8975_REG_CNTL_MODE_POWER_DOWN 0x00
#define AK8975_REG_CNTL_MODE_ONCE 0x01
#define AK8975_REG_CNTL_MODE_SELF_TEST 0x08
@@ -94,8 +90,7 @@
#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_ST1_DRDY_MASK BIT(0)
#define AK09912_REG_HXL 0x11
#define AK09912_REG_HXH 0x12
@@ -106,8 +101,7 @@
#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_ST2_HOFL_MASK BIT(3)
#define AK09912_REG_CNTL1 0x30
@@ -116,8 +110,7 @@
#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_CNTL2_MODE_MASK GENMASK(4, 0)
#define AK09912_REG_CNTL3 0x32
@@ -864,7 +857,10 @@ static const struct iio_chan_spec ak8975_channels[] = {
IIO_CHAN_SOFT_TIMESTAMP(AK8975_CHAN_TS),
};
-static const unsigned long ak8975_scan_masks[] = { 0x7, 0 };
+static const unsigned long ak8975_scan_masks[] = {
+ BIT(AK8975_CHAN_X) | BIT(AK8975_CHAN_Y) | BIT(AK8975_CHAN_Z),
+ 0
+};
static const struct iio_info ak8975_info = {
.read_raw = &ak8975_read_raw,
--
2.55.0
^ permalink raw reply [flat|nested] 6+ messages in thread
end of thread, other threads:[~2026-09-20 18:05 UTC | newest]
Thread overview: 6+ messages (download: mbox.gz / follow: Atom feed)
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2026-09-20 18:05 [PATCH v9 0/5] iio: magnetometer: ak8975: driver cleanup Joshua Crofts
2026-09-20 18:05 ` [PATCH v9 1/5] iio: magnetometer: ak8975: switch to using managed resources Joshua Crofts
2026-09-20 18:05 ` [PATCH v9 2/5] iio: magnetometer: ak8975: unify messages with help of dev_err_probe() Joshua Crofts
2026-09-20 18:05 ` [PATCH v9 3/5] iio: magnetometer: ak8975: use temporary variable for struct device Joshua Crofts
2026-09-20 18:05 ` [PATCH v9 4/5] iio: magnetometer: ak8975: add scan mask index enum Joshua Crofts
2026-09-20 18:05 ` [PATCH v9 5/5] iio: magnetometer: ak8975: make use of the macros from bits.h Joshua Crofts
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