Re: [PATCH v4 2/4] extcon: Added extcon_alloc_cables to simplify extcon register function

From: Chanwoo Choi
Date: Mon Mar 13 2023 - 07:07:47 EST


On 23. 3. 13. 20:06, Chanwoo Choi wrote:
> On 23. 3. 2. 18:01, Bumwoo Lee wrote:
>> The cable allocation part is functionalized from extcon_dev_register.
>>
>> Signed-off-by: Bumwoo Lee <bw365.lee@xxxxxxxxxxx>
>> ---
>> drivers/extcon/extcon.c | 108 +++++++++++++++++++++++-----------------
>> 1 file changed, 62 insertions(+), 46 deletions(-)
>>
>> diff --git a/drivers/extcon/extcon.c b/drivers/extcon/extcon.c
>> index adcf01132f70..49605e96bedd 100644
>> --- a/drivers/extcon/extcon.c
>> +++ b/drivers/extcon/extcon.c
>> @@ -1070,6 +1070,63 @@ void extcon_dev_free(struct extcon_dev *edev)
>> }
>> EXPORT_SYMBOL_GPL(extcon_dev_free);
>>
>> +/**
>> + * extcon_alloc_cables() - alloc the cables for extcon device
>> + * @edev: extcon device which has cables
>> + *
>> + * Returns 0 if success or error number if fail.
>> + */
>> +static int extcon_alloc_cables(struct extcon_dev *edev)
>> +{
>> + int index;
>> + char *str;
>> + struct extcon_cable *cable;
>> +
>> + if (!edev->max_supported)
>> + return 0;
>
>
> Need to check whether edev is NULL or not
> because make the separate function.
>
> if (!edev && !edev->max_supported)


Instead of previous my comment, need to check it as following:

if (!edev)
return -EINVAL;


if (!edev->max_supported)
return 0;


>
>> +
>> + edev->cables = kcalloc(edev->max_supported,
>> + sizeof(struct extcon_cable),
>> + GFP_KERNEL);
>> + if (!edev->cables)
>> + return -ENOMEM;
>> +
>> + for (index = 0; index < edev->max_supported; index++) {
>> + cable = &edev->cables[index];
>> +
>> + str = kasprintf(GFP_KERNEL, "cable.%d", index);
>> + if (!str) {
>> + for (index--; index >= 0; index--) {
>> + cable = &edev->cables[index];
>> + kfree(cable->attr_g.name);
>> + }
>> +
>> + kfree(edev->cables);
>> + return -ENOMEM;
>> + }
>> +
>> + cable->edev = edev;
>> + cable->cable_index = index;
>> + cable->attrs[0] = &cable->attr_name.attr;
>> + cable->attrs[1] = &cable->attr_state.attr;
>> + cable->attrs[2] = NULL;
>> + cable->attr_g.name = str;
>> + cable->attr_g.attrs = cable->attrs;
>> +
>> + sysfs_attr_init(&cable->attr_name.attr);
>> + cable->attr_name.attr.name = "name";
>> + cable->attr_name.attr.mode = 0444;
>> + cable->attr_name.show = cable_name_show;
>> +
>> + sysfs_attr_init(&cable->attr_state.attr);
>> + cable->attr_state.attr.name = "state";
>> + cable->attr_state.attr.mode = 0444;
>> + cable->attr_state.show = cable_state_show;
>> + }
>> +
>> + return 0;
>> +}
>> +
>> /**
>> * extcon_dev_register() - Register an new extcon device
>> * @edev: the extcon device to be registered
>> @@ -1117,50 +1174,9 @@ int extcon_dev_register(struct extcon_dev *edev)
>> dev_set_name(&edev->dev, "extcon%lu",
>> (unsigned long)atomic_inc_return(&edev_no));
>>
>> - if (edev->max_supported) {
>> - char *str;
>> - struct extcon_cable *cable;
>> -
>> - edev->cables = kcalloc(edev->max_supported,
>> - sizeof(struct extcon_cable),
>> - GFP_KERNEL);
>> - if (!edev->cables) {
>> - ret = -ENOMEM;
>> - goto err_sysfs_alloc;
>> - }
>> - for (index = 0; index < edev->max_supported; index++) {
>> - cable = &edev->cables[index];
>> -
>> - str = kasprintf(GFP_KERNEL, "cable.%d", index);
>> - if (!str) {
>> - for (index--; index >= 0; index--) {
>> - cable = &edev->cables[index];
>> - kfree(cable->attr_g.name);
>> - }
>> - ret = -ENOMEM;
>> -
>> - goto err_alloc_cables;
>> - }
>> -
>> - cable->edev = edev;
>> - cable->cable_index = index;
>> - cable->attrs[0] = &cable->attr_name.attr;
>> - cable->attrs[1] = &cable->attr_state.attr;
>> - cable->attrs[2] = NULL;
>> - cable->attr_g.name = str;
>> - cable->attr_g.attrs = cable->attrs;
>> -
>> - sysfs_attr_init(&cable->attr_name.attr);
>> - cable->attr_name.attr.name = "name";
>> - cable->attr_name.attr.mode = 0444;
>> - cable->attr_name.show = cable_name_show;
>> -
>> - sysfs_attr_init(&cable->attr_state.attr);
>> - cable->attr_state.attr.name = "state";
>> - cable->attr_state.attr.mode = 0444;
>> - cable->attr_state.show = cable_state_show;
>> - }
>> - }
>> + ret = extcon_alloc_cables(edev);
>> + if (ret < 0)
>> + goto err_alloc_cables;
>>
>> if (edev->max_supported && edev->mutually_exclusive) {
>> char *name;
>> @@ -1279,10 +1295,10 @@ int extcon_dev_register(struct extcon_dev *edev)
>> err_muex:
>> for (index = 0; index < edev->max_supported; index++)
>> kfree(edev->cables[index].attr_g.name);
>> -err_alloc_cables:
>> if (edev->max_supported)
>> kfree(edev->cables);
>> -err_sysfs_alloc:
>> +err_alloc_cables:
>> +
>> return ret;
>> }
>> EXPORT_SYMBOL_GPL(extcon_dev_register);
>

--
Best Regards,
Samsung Electronics
Chanwoo Choi