[PATCH AUTOSEL 5.4 083/130] iio: accel: bmc150: Check for a second ACPI device for BOSC0200

Sasha Levin
2020-12-23T02:21:10Z

From: Jeremy Cline <jeremy@jcline.org>

[ Upstream commit 5bfb3a4bd8f6b5329464edb9b772738708509d4a ]

Some BOSC0200 acpi_device-s describe two accelerometers in a single ACPI
device. Normally we would handle this by letting the special
drivers/platform/x86/i2c-multi-instantiate.c driver handle the BOSC0200
ACPI id and let it instantiate 2 bmc150_accel type i2c_client-s for us.

But doing so changes the modalias for the first accelerometer
(which is already supported and used on many devices) from
acpi:BOSC0200 to i2c:bmc150_accel. The modalias is not only used
to load the driver, but is also used by hwdb matches in
/lib/udev/hwdb.d/60-sensor.hwdb which provide a mountmatrix to
userspace by setting the ACCEL_MOUNT_MATRIX udev property.

Switching the handling of the BOSC0200 over to i2c-multi-instantiate.c
will break the hwdb matches causing the ACCEL_MOUNT_MATRIX udev prop
to no longer be set. So switching over to i2c-multi-instantiate.c is
not an option.

Changes by Hans de Goede:
-Add explanation to the commit message why i2c-multi-instantiate.c
cannot be used
-Also set the dev_name, fwnode and irq i2c_board_info struct members
for the 2nd client

Signed-off-by: Jeremy Cline <jeremy@jcline.org>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Link: https://lore.kernel.org/r/20201130141954.339805-2-hdegoede@redhat.com
BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=198671
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/iio/accel/bmc150-accel-core.c | 21 ++++++++++++++
drivers/iio/accel/bmc150-accel-i2c.c | 41 +++++++++++++++++++++++++--
drivers/iio/accel/bmc150-accel.h | 2 ++
3 files changed, 62 insertions(+), 2 deletions(-)

diff --git a/drivers/iio/accel/bmc150-accel-core.c b/drivers/iio/accel/bmc150-accel-core.c
index bcdf25f32e220..f63743a62d2ed 100644
--- a/drivers/iio/accel/bmc150-accel-core.c
+++ b/drivers/iio/accel/bmc150-accel-core.c
@@ -204,6 +204,7 @@ struct bmc150_accel_data {
int ev_enable_state;
int64_t timestamp, old_timestamp; /* Only used in hw fifo mode. */
const struct bmc150_accel_chip_info *chip_info;
+ struct i2c_client *second_device;
struct iio_mount_matrix orientation;
};

@@ -1663,6 +1664,26 @@ int bmc150_accel_core_probe(struct device *dev, struct regmap *regmap, int irq,
}
EXPORT_SYMBOL_GPL(bmc150_accel_core_probe);

+struct i2c_client *bmc150_get_second_device(struct i2c_client *client)
+{
+ struct bmc150_accel_data *data = i2c_get_clientdata(client);
+
+ if (!data)
+ return NULL;
+
+ return data->second_device;
+}
+EXPORT_SYMBOL_GPL(bmc150_get_second_device);
+
+void bmc150_set_second_device(struct i2c_client *client)
+{
+ struct bmc150_accel_data *data = i2c_get_clientdata(client);
+
+ if (data)
+ data->second_device = client;
+}
+EXPORT_SYMBOL_GPL(bmc150_set_second_device);
+
int bmc150_accel_core_remove(struct device *dev)
{
struct iio_dev *indio_dev = dev_get_drvdata(dev);
diff --git a/drivers/iio/accel/bmc150-accel-i2c.c b/drivers/iio/accel/bmc150-accel-i2c.c
index 06021c8685a70..8c45963fe3cdb 100644
--- a/drivers/iio/accel/bmc150-accel-i2c.c
+++ b/drivers/iio/accel/bmc150-accel-i2c.c
@@ -29,6 +29,8 @@ static int bmc150_accel_probe(struct i2c_client *client,
i2c_check_functionality(client->adapter, I2C_FUNC_I2C) ||
i2c_check_functionality(client->adapter,
I2C_FUNC_SMBUS_READ_I2C_BLOCK);
+ struct acpi_device __maybe_unused *adev;
+ int ret;

regmap = devm_regmap_init_i2c(client, &bmc150_regmap_conf);
if (IS_ERR(regmap)) {
@@ -39,12 +41,47 @@ static int bmc150_accel_probe(struct i2c_client *client,
if (id)
name = id->name;

- return bmc150_accel_core_probe(&client->dev, regmap, client->irq, name,
- block_supported);
+ ret = bmc150_accel_core_probe(&client->dev, regmap, client->irq, name, block_supported);
+ if (ret)
+ return ret;
+
+ /*
+ * Some BOSC0200 acpi_devices describe 2 accelerometers in a single ACPI
+ * device, try instantiating a second i2c_client for an I2cSerialBusV2
+ * ACPI resource with index 1. The !id check avoids recursion when
+ * bmc150_accel_probe() gets called for the second client.
+ */
+#ifdef CONFIG_ACPI
+ adev = ACPI_COMPANION(&client->dev);
+ if (!id && adev && strcmp(acpi_device_hid(adev), "BOSC0200") == 0) {
+ struct i2c_board_info board_info = {
+ .type = "bmc150_accel",
+ /*
+ * The 2nd accel sits in the base of 2-in-1s. Note this
+ * name is static, as there should never be more then 1
+ * BOSC0200 ACPI node with 2 accelerometers in it.
+ */
+ .dev_name = "BOSC0200:base",
+ .fwnode = client->dev.fwnode,
+ .irq = -ENOENT,
+ };
+ struct i2c_client *second_dev;
+
+ second_dev = i2c_acpi_new_device(&client->dev, 1, &board_info);
+ if (!IS_ERR(second_dev))
+ bmc150_set_second_device(second_dev);
+ }
+#endif
+
+ return 0;
}

static int bmc150_accel_remove(struct i2c_client *client)
{
+ struct i2c_client *second_dev = bmc150_get_second_device(client);
+
+ i2c_unregister_device(second_dev);
+
return bmc150_accel_core_remove(&client->dev);
}

diff --git a/drivers/iio/accel/bmc150-accel.h b/drivers/iio/accel/bmc150-accel.h
index ae6118ae11b1d..6e965a3ca3226 100644
--- a/drivers/iio/accel/bmc150-accel.h
+++ b/drivers/iio/accel/bmc150-accel.h
@@ -16,6 +16,8 @@ enum {
int bmc150_accel_core_probe(struct device *dev, struct regmap *regmap, int irq,
const char *name, bool block_supported);
int bmc150_accel_core_remove(struct device *dev);
+struct i2c_client *bmc150_get_second_device(struct i2c_client *second_device);
+void bmc150_set_second_device(struct i2c_client *second_device);
extern const struct dev_pm_ops bmc150_accel_pm_ops;
extern const struct regmap_config bmc150_regmap_conf;

--
2.27.0