Seforno suggests that Yosef refrained from sending a message to his father, Yaakov, because he interpreted his dreams as indicating that his fate was divinely decreed, and thus he believed it was improper to interfere with God's plan.
וַיִּזְכֹּר יוֹסֵף אֵת הַחֲלוֹמוֹת אֲשֶׁר חָלַם לָהֶם. זָכַר לָהֶם אֶת הַחֲלוֹמוֹת, שֶׁבַּחֲלוֹם הָאֲלוּמּוֹת הָיוּ כֻּלָּם מִשְׁתַּחֲוִים, וְשֶׁאֲלֻמָּתוֹ קָמָה וְגַם נִצָּבָה שֶׁלֹּא נָפְלָה אַחַר שֶׁקָּמָה. וְלָכֵן רָצָה שֶׁיָּבֹאוּ כֻּלָּם וִיבַשְּׂרֵם וְיִתְקַיֵּם בּוֹ עִנְיַן "וְגַם נִצָּבָה". וְזֶה בִּזְכוּת שֶׁיִּהְיֶה הוּא רֶמֶז לַגּוֹאֵל הֶעָתִיד עַל דֶּרֶךְ "יְרֵה וַיּוֹר" (מלכים ב יג:יז), כְּאָמְרוֹ "וְנִקְבְּצוּ בְּנֵי יְהוּדָה וּבְנֵי יִשְׂרָאֵל יַחְדָּיו וְשָׂמוּ לָהֶם רֹאשׁ אֶחָד" (הושע ב:ב), וְיִתְקַיֵּם בָּהֶם עִנְיַן "וְגַם נִצָּבָה" כְּאָמְרוֹ "מַלְכוּ דִּי לְעָלְמִין לָא תִתְחַבַּל" (דניאל ב:מד).
ויזכור יוסף את החלמות אשר חלם להם. He remembered the part his brothers had played in his dreams, how they had bowed down to him in the dream showing the sheaves of corn. (37,7) He remembered that only his own sheaf had remained erect, and not fallen after first having arisen. This is why he wanted that they would all come when he would recognise them and the part in the dream speaking of the upright sheaf remaining upright would be fulfilled also. This detail of the dream was due to Joseph symbolising the redeemer of the Jewish people in the future as portrayed by the words ירה ויור, “shoot!, and he shot”. in Kings II 13,17. [this was an opportunity, though missed because of the king of Israel not complying completely with the prophet Elisha’s instructions, of reuniting the kingdoms of Yehudah and the Kingdom of Israel. i.e. that of Ephrayim, the descendant of Joseph. Ed.] There were several such opportunities foreseen by the prophets compare Hoseah 2,2 and Daniel 2,44. The author does not really elaborate. Ed.]