Canon EOS M Instruction Manual page 124

Changing the Focusing Method
Using Continuous AF
The default setting is [Enable].
Since the focus is constantly close to the subject, when you press the
shutter button, the camera quickly focuses the subject. If [Enable] is
set, the lens will operate frequently and consume more battery power.
This will reduce the number of possible shots (battery life).
When an EF or EF-S lens is used, during Continuous AF, turn off the
power before setting the lens's focus mode switch to <MF>.
Using AF+MF Mode (Full-time manual focusing) Using AF+MF Mode (Full-time manual focusing) Using AF+MF Mode (Full-time manual focusing)
Set the Focus mode to [AF+MF].
After focus is achieved using AF, you can adjust the focus manually as After focus is achieved using AF, you can adjust the focus manually as After focus is achieved using AF, you can adjust the focus manually as
desired using the focusing ring while holding the shutter button pressed desired using the focusing ring while holding the shutter button pressed desired using the focusing ring while holding the shutter button pressed
halfway.
However, in <5> mode (p.81) or if [AF operation] is set to [Servo AF]
(p.131), priority is given to Servo AF. In such cases, even if you set the (p.131), priority is given to Servo AF. In such cases, even if you set the (p.131), priority is given to Servo AF. In such cases, even if you set the
focus mode to [AF+MF], you will not be able to focus manually.
124
> mode (p.81) or if > mode (p.81) or if [
], you will not be able to focus manually. ], you will not be able to focus manually.
[AF operation AF operation