Forced Fast Charge for Samsung Galaxy S3/N2 v1.5 by Yank555.lu
SysFS interface :

 * /sys/kernel/fast_charge/force_fast_charge (rw)
 *
 *   0 - disabled (default)
 *   1 - substitute AC to USB
 *   2 - use custom mA configured through sysfs interface (see below)
 *
 * /sys/kernel/fast_charge/ac_charge_level (rw)
 *
 *   rate at which to charge when on AC (1.0A/h to 1.5A/h)
 *
 * /sys/kernel/fast_charge/usb_charge_level (r/w)
 *
 *   rate at which to charge when on USB (0.475A/h to 1.0A/h)
 *
 * /sys/kernel/fast_charge/wireless_charge_level (r/w)
 *
 *   rate at which to charge when on wireless (0.475A/h to 1.0A/h)
 *
 * /sys/kernel/fast_charge/failsafe (rw)
 *
 *   0 - disabled - allow anything up to 2.1A/h to be used as AC / USB custom current
 *   1 - enabled  - behaviour as described above (default)
 *
 * /sys/kernel/fast_charge/ac_leves (ro)
 *
 *   display available levels for AC (for failsafe enabled mode)
 *
 * /sys/kernel/fast_charge/usb_levels (ro)
 *
 *   display available levels for USB (for failsafe enabled mode)
 *
 * /sys/kernel/fast_charge/wireless_levels (ro)
 *
 *   display available levels for wireless (for failsafe enabled mode)
 *
 * /sys/kernel/fast_charge/version (ro)
 *
 *   display fast charge version information
 *
 * /sys/kernel/fast_charge/info (ro)
 *
 *   display complete fast charge configuration in human readable format

Credits to Chad Froebel <chadfroebel@gmail.com> for the base.
Credits to Yank555.lu for ported to S3/N2