Hi Roger,
I add minor comment about code clean.
After I modified it by myself, I applied it on extcon-fixes.
Best Regards,
Chanwoo Choi
On 07/07/2015 10:06 PM, Roger Quadros wrote:
> Users of find_cable_index_by_name() will cause a kernel hang
> as the while loop counter is never incremented and end condition
> is never reached.
>
> extcon_get_cable_state() and extcon_set_cable_state() are broken
> because they use cable index instead of cable id. This causes
> the first cable state (cable.0) to be always invalid in sysfs
> or extcon_get_cable_state() users.
>
> Introduce a new function find_cable_id_by_name() that fixes
> both of the above issues.
>
> Fixes: commit 73b6ecdb93e8 ("extcon: Redefine the unique id of supported external connectors without 'enum extcon' type")
> Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
> Signed-off-by: Roger Quadros <rogerq@xxxxxx>
> ---
> drivers/extcon/extcon.c | 38 +++++++++++++++++++++++++++++---------
> 1 file changed, 29 insertions(+), 9 deletions(-)
>
> diff --git a/drivers/extcon/extcon.c b/drivers/extcon/extcon.c
> index 76157ab..987dd3c 100644
> --- a/drivers/extcon/extcon.c
> +++ b/drivers/extcon/extcon.c
> @@ -124,22 +124,34 @@ static int find_cable_index_by_id(struct extcon_dev *edev, const unsigned int id
> return -EINVAL;
> }
>
> -static int find_cable_index_by_name(struct extcon_dev *edev, const char *name)
> +static int find_cable_id_by_name(struct extcon_dev *edev, const char *name)
> {
> - unsigned int id = EXTCON_NONE;
> + unsigned int id = -EINVAL;
> int i = 0;
>
> - if (edev->max_supported == 0)
> - return -EINVAL;
> -
> - /* Find the the number of extcon cable */
> + /* Find the id of extcon cable */
> while (extcon_name[i]) {
> if (!strncmp(extcon_name[i], name, CABLE_NAME_MAX)) {
> id = i;
> break;
> }
> +
Remove blank line.
> + i++;
> }
>
> + return id;
> +};
> +
> +static int find_cable_index_by_name(struct extcon_dev *edev, const char *name)
> +{
> + unsigned int id = EXTCON_NONE;
> +
> + if (edev->max_supported == 0)
> + return -EINVAL;
> +
> + /* Find the the number of extcon cable */
> + id = find_cable_id_by_name(edev, name);
> +
> if (id == EXTCON_NONE)
> return -EINVAL;
>
> @@ -228,9 +240,11 @@ static ssize_t cable_state_show(struct device *dev,
> struct extcon_cable *cable = container_of(attr, struct extcon_cable,
> attr_state);
>
> + int i = cable->cable_index;
> +
> return sprintf(buf, "%d\n",
> extcon_get_cable_state_(cable->edev,
> - cable->cable_index));
> + cable->edev->supported_cable[i]));
> }
>
> /**
> @@ -341,6 +355,9 @@ int extcon_get_cable_state_(struct extcon_dev *edev, const unsigned int id)
> {
> int index;
>
> + if (id == EXTCON_NONE)
> + return -EINVAL;
> +
This if statement don't be necessary.
Instead, I check the error value on extcon_get_cable_state() by checking the
return value of find_cable_id_by_name().
> index = find_cable_index_by_id(edev, id);
> if (index < 0)
> return index;
> @@ -361,7 +378,7 @@ EXPORT_SYMBOL_GPL(extcon_get_cable_state_);
> */
> int extcon_get_cable_state(struct extcon_dev *edev, const char *cable_name)
> {
> - return extcon_get_cable_state_(edev, find_cable_index_by_name
> + return extcon_get_cable_state_(edev, find_cable_id_by_name
> (edev, cable_name));
I modified it as following:
unsigned int id;
id = find_cable_id_by_name(edev, cable_name);
if (id < 0)
return id;
return extcon_get_cable_state_(edev, id);
> }
> EXPORT_SYMBOL_GPL(extcon_get_cable_state);
> @@ -380,6 +397,9 @@ int extcon_set_cable_state_(struct extcon_dev *edev, unsigned int id,
> u32 state;
> int index;
>
> + if (id == EXTCON_NONE)
> + return -EINVAL;
> +
ditto.
> index = find_cable_index_by_id(edev, id);
> if (index < 0)
> return index;
> @@ -404,7 +424,7 @@ EXPORT_SYMBOL_GPL(extcon_set_cable_state_);
> int extcon_set_cable_state(struct extcon_dev *edev,
> const char *cable_name, bool cable_state)
> {
> - return extcon_set_cable_state_(edev, find_cable_index_by_name
> + return extcon_set_cable_state_(edev, find_cable_id_by_name
> (edev, cable_name), cable_state);
ditto.
Thanks,
Chanwoo Choi
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