[PATCH linux dev-4.7] drivers/fsi: Free up allocated resources on fsi-master unbind

[Eddie James]

On 03/08/2017 01:56 PM, Christopher Bostic wrote:
> In order to allow repeated bind/unbind operations on fsi-master
> the resources allocated during bind must be freed. Specifically
> the scan file and dynamic memory.  Also check for valid pointers
> during unregister which is the path taken during unbind.
>
> Signed-off-by: Christopher Bostic <cbostic at linux.vnet.ibm.com>
> ---
>   drivers/fsi/fsi-core.c        | 8 ++++----
>   drivers/fsi/fsi-master-gpio.c | 2 ++
>   2 files changed, 6 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/fsi/fsi-core.c b/drivers/fsi/fsi-core.c
> index bbdf6b8..751c767 100644
> --- a/drivers/fsi/fsi-core.c
> +++ b/drivers/fsi/fsi-core.c
> @@ -869,11 +869,11 @@ EXPORT_SYMBOL_GPL(fsi_master_register);
>
>   void fsi_master_unregister(struct fsi_master *master)
>   {
> -	if (master->idx >= 0) {
> -		ida_simple_remove(&master_ida, master->idx);
> -		master->idx = -1;
> -	}
> +	if (!master || !master->dev || master->idx < 0)
> +		return;
>
> +	ida_simple_remove(&master_ida, master->idx);
> +	master->idx = -1;
>   	device_remove_file(master->dev, &dev_attr_fsi_ipoll_period);
>   	fsi_master_unscan(master);
>   	put_device(master->dev);
> diff --git a/drivers/fsi/fsi-master-gpio.c b/drivers/fsi/fsi-master-gpio.c
> index 49f3399..3693b3d 100644
> --- a/drivers/fsi/fsi-master-gpio.c
> +++ b/drivers/fsi/fsi-master-gpio.c
> @@ -566,6 +566,8 @@ static int fsi_master_gpio_remove(struct platform_device *pdev)
>   	if (master->gpio_mux)
>   		devm_gpiod_put(&pdev->dev, master->gpio_mux);
>   	fsi_master_unregister(&master->master);
> +	device_remove_file(&pdev->dev, &dev_attr_scan);
> +	devm_kfree(&pdev->dev, master);

I think this devm_kfree call is unnecessary. Since this is in remove(), 
it should get freed automatically when the device is freed by the kernel.

Thanks,
Eddie

>
>   	return 0;
>   }