How will we reconcile the current Pasuk, which refers to Calev's father as 'Yefuneh', with the Pasuk in Divrei ha'Yamim 1, 2:18, which refers to him as 'Chetzron'?
Rashi (in Divrei ha'Yamim 1 4:15) and Chizkuni (citing Sotah 11b): His real name was "Calev ben Chetzron", and the Torah only calls him "Calev ben Yefuneh" because he turned away (Panah) from the counsel of the spies. 1
Ibn Ezra (Peirush ha'Katzar, Sh'mos 24:12): The two Pesukim are referring to different people. 2
The Yerushalmi (in Yevamos 10:7, be'Sof) says 'like the opinion that they are the same'. This implies that some hold that they are different. Gur Aryeh (Sh'mos 35:30) points out that this Calev's daughter was Achsah (Yehoshua 15:17), and so was Calev ben Chetzron's daughter (Divrei ha'Yamim 1:2:49). This shows that they were the same, unless you will say that both of them had a daughter named Achsah.
That is precisely the question? According to mome opinion in Sotah 11b, Calev was the son of Chetzron, and the step-son of Yefuneh who married his (Calev's) mother after Chetzron died..