[PATCH 4/8] iio: accel: bmc150: Add support for dual-accelerometers with a DUAL250E HID

[Hans de Goede]

Hi,

On 5/22/21 7:43 PM, Jonathan Cameron wrote:
> On Fri, 21 May 2021 19:14:14 +0200
> Hans de Goede <hdegoede at redhat.com> wrote:
> 
>> The Lenovo Yoga 300-11IBR has a ACPI fwnode with a HID of DUAL250E
>> which contains I2C and IRQ resources for 2 accelerometers, 1 in the
>> display and one in the base of the device. Add support for this.
>>
>> Signed-off-by: Hans de Goede <hdegoede at redhat.com>
>> ---
>>  drivers/iio/accel/bmc150-accel-i2c.c | 19 ++++++++++++-------
>>  1 file changed, 12 insertions(+), 7 deletions(-)
>>
>> diff --git a/drivers/iio/accel/bmc150-accel-i2c.c b/drivers/iio/accel/bmc150-accel-i2c.c
>> index e24ce28a4660..b81e4005788e 100644
>> --- a/drivers/iio/accel/bmc150-accel-i2c.c
>> +++ b/drivers/iio/accel/bmc150-accel-i2c.c
>> @@ -24,6 +24,7 @@
>>  #ifdef CONFIG_ACPI
>>  static const struct acpi_device_id bmc150_acpi_dual_accel_ids[] = {
>>  	{"BOSC0200"},
>> +	{"DUAL250E"},
>>  	{ },
>>  };
>>  
>> @@ -35,21 +36,24 @@ static void bmc150_acpi_dual_accel_probe(struct i2c_client *client)
>>  {
>>  	struct acpi_device *adev = ACPI_COMPANION(&client->dev);
>>  	struct i2c_client *second_dev;
>> +	char dev_name[16];
> 
> I'm a bit in two minds about having a fixed length array for this.
> Obviously this is always big enough (I think a bit too big), but it
> might be a place where a future bug is introduced.  Perhaps it's worth the dance
> of a kasprintf and kfree, to avoid that possibility?

I would prefer to keep this as is, using malloc + free always leads
to problems if an error-exit path shows up between the 2.

But if you've a strong preference for switching to
kasprintf + kfree I can do that for v2.

Regards,

Hans



> 
>>  	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",
>> +		.dev_name = dev_name,
>>  		.fwnode = client->dev.fwnode,
>> -		.irq = -ENOENT,
>>  	};
>>  
>>  	if (acpi_match_device_ids(adev, bmc150_acpi_dual_accel_ids))
>>  		return;
>>  
>> +	/*
>> +	 * The 2nd accel sits in the base of 2-in-1s. The suffix is static, as
>> +	 * there should never be more then 1 ACPI node with 2 accelerometers in it.
>> +	 */
>> +	snprintf(dev_name, sizeof(dev_name), "%s:base", acpi_device_hid(adev));
>> +
>> +	board_info.irq = acpi_dev_gpio_irq_get_by(adev, NULL, 1);
>> +
>>  	second_dev = i2c_acpi_new_device(&client->dev, 1, &board_info);
>>  	if (!IS_ERR(second_dev))
>>  		bmc150_set_second_device(client, second_dev);
>> @@ -114,6 +118,7 @@ static const struct acpi_device_id bmc150_accel_acpi_match[] = {
>>  	{"BMA222E",	bma222e},
>>  	{"BMA0280",	bma280},
>>  	{"BOSC0200"},
>> +	{"DUAL250E"},
>>  	{ },
>>  };
>>  MODULE_DEVICE_TABLE(acpi, bmc150_accel_acpi_match);
>