Re: [PATCH v3 3/6] platform/x86: dell-smo8800: Move instantiation of lis3lv02d i2c_client from i2c-i801 to dell-smo8800

[Hans de Goede <hdegoede@redhat.com>]

Hi,

On 6/22/24 5:35 PM, Pali Rohár wrote:
> On Friday 21 June 2024 14:24:58 Hans de Goede wrote:
>> +static void smo8800_instantiate_i2c_client(struct work_struct *work)
>> +{
>> +	struct smo8800_device *smo8800 =
>> +		container_of(work, struct smo8800_device, i2c_work);
>> +	const struct dmi_system_id *lis3lv02d_dmi_id;
>> +	struct i2c_board_info info = { };
>> +	struct i2c_adapter *adap = NULL;
>> +
>> +	if (smo8800->i2c_dev)
>> +		return;
>> +
>> +	bus_for_each_dev(&i2c_bus_type, NULL, &adap, smo8800_find_i801);
>> +	if (!adap)
>> +		return;
>> +
>> +	lis3lv02d_dmi_id = dmi_first_match(smo8800_lis3lv02d_devices);
> 
> Result of this function call is always same. You can call it just once,
> e.g. in module __init section and store cached result.

This function will only run when a new main i2c-i801 adapter shows up.
Which normally only happens once per boot, so there is no need to
make things more complex to optimize this.

Regards,

Hans


> 
>> +	if (!lis3lv02d_dmi_id)
>> +		goto out_put_adapter;
>> +
>> +	info.addr = (long)lis3lv02d_dmi_id->driver_data;
>> +	strscpy(info.type, "lis3lv02d", I2C_NAME_SIZE);
>> +
>> +	smo8800->i2c_dev = i2c_new_client_device(adap, &info);
>> +	if (IS_ERR(smo8800->i2c_dev)) {
>> +		dev_err(smo8800->dev, "error %ld registering %s i2c_client\n",
>> +			PTR_ERR(smo8800->i2c_dev), info.type);
>> +		smo8800->i2c_dev = NULL;
>> +	} else {
>> +		dev_dbg(smo8800->dev, "registered %s i2c_client on address 0x%02x\n",
>> +			info.type, info.addr);
>> +	}
>> +
>> +out_put_adapter:
>> +	i2c_put_adapter(adap);
>> +}
>