Re: [PATCH 1/9] staging:iio:hmc5843: Drop I2C detection code

[Jonathan Cameron <jic23@kernel.org>]

On 07/27/13 16:31, Peter Meerwald wrote:
> I2C is generally not probed for devices
I wondered about this one for a while, as in some circumstances it is pretty
much the only option (hwmon drivers on random super i/o modules etc).

I'm a little worried someone might actually be using this functionality.
As the class is not specified, according to the i2c docs detection will only
function if the module is forced to load.  Also the function here does not,
as the docs specify it must, fill in the name field of the i2c_board_info structure.

Thus I'm going to drop it and see if anyone shouts about putting it back.

Chances are no one is using this and it is a legacy from this driver being
based on something in hwmon.

Jonathan
> 
> Signed-off-by: Peter Meerwald <pmeerw@pmeerw.net>
> Cc: Shubhrajyoti Datta <shubhrajyoti@ti.com>
> ---
>  drivers/staging/iio/magnetometer/hmc5843.c | 33 ------------------------------
>  1 file changed, 33 deletions(-)
> 
> diff --git a/drivers/staging/iio/magnetometer/hmc5843.c b/drivers/staging/iio/magnetometer/hmc5843.c
> index 86c6bf9..e5999d4 100644
> --- a/drivers/staging/iio/magnetometer/hmc5843.c
> +++ b/drivers/staging/iio/magnetometer/hmc5843.c
> @@ -53,14 +53,6 @@ enum hmc5843_ids {
>  };
>  
>  /*
> - * Beware: identification of the HMC5883 is still "H43";
> - * I2C address is also unchanged
> - */
> -#define HMC5843_ID_REG_LENGTH			0x03
> -#define HMC5843_ID_STRING			"H43"
> -#define HMC5843_I2C_ADDRESS			0x1E
> -
> -/*
>   * Range gain settings in (+-)Ga
>   * Beware: HMC5843 and HMC5883 have different recommended sensor field
>   * ranges; default corresponds to +-1.0 Ga and +-1.3 Ga, respectively
> @@ -185,10 +177,6 @@ static const char * const hmc5883_regval_to_sample_freq[] = {
>  	"0.75", "1.5", "3", "7.5", "15", "30", "75",
>  };
>  
> -/* Addresses to scan: 0x1E */
> -static const unsigned short normal_i2c[] = { HMC5843_I2C_ADDRESS,
> -					     I2C_CLIENT_END };
> -
>  /* Describe chip variants */
>  struct hmc5843_chip_info {
>  	const struct iio_chan_spec *channels;
> @@ -621,25 +609,6 @@ static const struct hmc5843_chip_info hmc5843_chip_info_tbl[] = {
>  	},
>  };
>  
> -static int hmc5843_detect(struct i2c_client *client,
> -			  struct i2c_board_info *info)
> -{
> -	unsigned char id_str[HMC5843_ID_REG_LENGTH];
> -
> -	if (client->addr != HMC5843_I2C_ADDRESS)
> -		return -ENODEV;
> -
> -	if (i2c_smbus_read_i2c_block_data(client, HMC5843_ID_REG_A,
> -				HMC5843_ID_REG_LENGTH, id_str)
> -			!= HMC5843_ID_REG_LENGTH)
> -		return -ENODEV;
> -
> -	if (0 != strncmp(id_str, HMC5843_ID_STRING, HMC5843_ID_REG_LENGTH))
> -		return -ENODEV;
> -
> -	return 0;
> -}
> -
>  /* Called when we have found a new HMC58X3 */
>  static void hmc5843_init_client(struct i2c_client *client,
>  				const struct i2c_device_id *id)
> @@ -756,8 +725,6 @@ static struct i2c_driver hmc5843_driver = {
>  	.id_table	= hmc5843_id,
>  	.probe		= hmc5843_probe,
>  	.remove		= hmc5843_remove,
> -	.detect		= hmc5843_detect,
> -	.address_list	= normal_i2c,
>  };
>  module_i2c_driver(hmc5843_driver);
>  
>