The answer is both! However, the Spirit comes specifically from the Father, even if it is the Son who is sending Him, as we can read here:
John 15:26 NKJV |
26"But when the Helper comes, whom I shall send to you from the Father, the Spirit of truth who proceeds from the Father, He will testify of Me. (Holy Bible: New King James Version. Nashville, Tennessee: Thomas Nelson Publishers, 1982.) |
I would also like to point out that these passages are evidence against the claim that the Holy Spirit is co-equal with God, since Jesus is also recorded as saying this:
John 13:16 NKJV |
16Most assuredly, I say to you, a servant is not greater than his master; nor is he who is sent greater than he who sent him. (Holy Bible: New King James Version. Nashville, Tennessee: Thomas Nelson Publishers, 1982.) |
Who is greater, the one sent or the one who sent him? Jesus said, "he who sent him". Who send the Holy Spirit? As you cited: both the Son and the Father. Hence, the Holy Spirit is not co-equal with them, but rather, the Father and Son are greater.
Now, although both the Son and Father send the Holy Spirit, does that mean that the Son is co-equal with the Father?
John 14:28 NKJV |
28You have heard Me say to you, "I am going away and coming back to you." If you loved Me, you would rejoice because I said, "I am going to the Father," for My Father is greater than I. (Holy Bible: New King James Version. Nashville, Tennessee: Thomas Nelson Publishers, 1982.) |
Who is greater than Jesus? Jesus said, "My Father".
This also poses the question: Can the Son and Holy Spirit be God if there is anyone who is greater than them?
Eph. 4:6 NKJV |
6one God and Father of all, who is above all, and through all, and in you all. (Holy Bible: New King James Version. Nashville, Tennessee: Thomas Nelson Publishers, 1982.) |
Who is above all? Paul said, "God". Hence, God has no equal, nor are there any greater than Him, which means that the Son and Holy Spirit are not God.
Rather, who is the one God who is above all? Paul said, "Father".