Re: [PATCH v5 WIP 3/5] i2c-parport: define ports to connect

[Jean Delvare <jdelvare@suse.de>]

Hi Sudip,

Le Wednesday 06 May 2015 à 15:46 +0530, Sudip Mukherjee a écrit :
> as of now i2c-parport was connecting to all the available parallel
> ports. Lets limit that to maximum of 4 instances and at the same time
> define which instance connects to which parallel port

A leading capital and a trailing dot would look better.

> Signed-off-by: Sudip Mukherjee <sudip@vectorindia.org>
> ---
>  drivers/i2c/busses/i2c-parport.c | 21 +++++++++++++++++++++
>  1 file changed, 21 insertions(+)
> 
> diff --git a/drivers/i2c/busses/i2c-parport.c b/drivers/i2c/busses/i2c-parport.c
> index a1fac5a..a9b25c3 100644
> --- a/drivers/i2c/busses/i2c-parport.c
> +++ b/drivers/i2c/busses/i2c-parport.c
> @@ -46,6 +46,9 @@ struct i2c_par {
>  
>  static LIST_HEAD(adapter_list);
>  static DEFINE_MUTEX(adapter_list_lock);
> +#define MAX_DEVICE 4
> +static int parport[MAX_DEVICE] = {0, -1, -1, -1};
> +
>  
>  /* ----- Low-level parallel port access ----------------------------------- */
>  
> @@ -163,6 +166,18 @@ static void i2c_parport_irq(void *data)
>  static void i2c_parport_attach(struct parport *port)
>  {
>  	struct i2c_par *adapter;
> +	int i;
> +
> +	for (i = 0; i < MAX_DEVICE; i++) {
> +		if (parport[i] == -1)
> +			continue;
> +		if (port->number == parport[i])
> +			break;
> +	}
> +	if (i == MAX_DEVICE) {
> +		pr_err("port mentioned not found\n");

This error message needs to be improved. Someone seeing this in his/her
logs would have no idea where it comes from and what it means exactly.
You want to add "i2c-parport: " at the beginning, and say which port
number was specified.

> +		return;
> +	}
>  
>  	adapter = kzalloc(sizeof(struct i2c_par), GFP_KERNEL);
>  	if (adapter == NULL) {
> @@ -298,5 +313,11 @@ MODULE_AUTHOR("Jean Delvare <jdelvare@suse.de>");
>  MODULE_DESCRIPTION("I2C bus over parallel port");
>  MODULE_LICENSE("GPL");
>  
> +module_param_array(parport, int, NULL, 0);
> +MODULE_PARM_DESC(parport, "Atmost 4 instances are allowed.\n"

You should first say what the parameter does, before going into the
details. Please use __stringify(MAX_DEVICE) instead of hard-coding 4, so
that it doesn't need to be updated if MAX_DEVICE ever changes.

> +			  "Mention portnumbers in array.\n"

Missing space between "port" and "numbers". Don't mention that this is
an array here, "modinfo" already prints the parameter type. For improved
readability, please also add a leading space to the second and following
lines (as done for parameter "type" in i2c-parport.h.)

> +			  "If the port is not to be used mention -1.\n"
> +			  "Default is one instance connected to parport0\n");

Missing trailing dot.

> +
>  module_init(i2c_parport_init);
>  module_exit(i2c_parport_exit);

I tested this patch and it works fine.

Tested-by: Jean Delvare <jdelvare@suse.de>

-- 
Jean Delvare
SUSE L3 Support