Finger sensing apparatus performing secure software update and associated methods

1. A finger sensing apparatus comprising:

a finger sensor comprising

an integrated circuit (IC) substrate,

an array of finger sensing elements on said IC substrate, and

secure software update circuitry on said IC substrate; and

a host platform external from said finger sensor and hosting software associated with said finger sensor, said host platform cooperating with said secure software update circuitry to authorize an attempted software update.

2. The finger sensing apparatus according to claim 1 , wherein said secure software update circuitry comprises at least one register.

3. The finger sensing apparatus according to claim 2 , wherein said finger sensor and said host platform cooperate to clear the at least one register.

4. The finger sensing apparatus according to claim 3 , wherein said finger sensor and said host platform cooperate to extend a software measurement value into the at least one cleared register based upon the attempted software update.

5. The finger sensing apparatus according to claim 4 , wherein said secure software update circuitry compares the extended software measurement value to a predicted value therefor.

6. The finger sensing apparatus according to claim 4 , wherein the predicted value is included in the attempted software update.

7. The finger sensing apparatus according to claim 2 , wherein said at least one register comprises at least one non-volatile register.

8. The finger sensing apparatus according to claim 1 , wherein the attempted software update comprises at least one finger sensor driver software update.

9. The finger sensing apparatus according to claim 1 , further comprising a housing carrying said finger sensor and said host platform.

10. An electronic device comprising:

a housing;

a finger sensor carried by said housing and comprising

an integrated circuit (IC) substrate,

an array of finger sensing elements on said IC substrate, and

secure software update circuitry on said IC substrate; and

a host platform carried by said housing and hosting software associated with said finger sensor, said host platform cooperating with said secure software update circuitry to authorize an attempted software update.

11. The electronic device according to claim 10 , wherein said secure software update circuitry comprises at least one register.

12. The electronic device according to claim 11 , wherein said finger sensor and said host platform cooperate to clear the at least one register and to extend a software measurement value into the at least one cleared register based upon the attempted software update.

13. The electronic device according to claim 12 , wherein said secure software update circuitry compares the extended software measurement value to a predicted value therefor in the attempted software update.

14. The electronic device according to claim 11 , wherein said at least one register comprises at least one non-volatile register.

15. The electronic device according to claim 11 , wherein the attempted software update comprises at least one finger sensor driver software update.

16. A method for updating software of a host platform hosting software associated with a finger sensor, the method comprising:

using secure update circuitry on an IC substrate of the finger sensor also comprising an array of finger sensing elements on the IC substrate in cooperation with the host platform to authorize an attempted software update; and

updating the software of the host platform based upon a successful authorization of the attempted software update.

17. The method according to claim 16 , wherein the secure software update circuitry comprises at least one register.

18. The method according to claim 17 , further comprising clearing the at least one register and extending a software measurement value into the at least one cleared register based upon the attempted software update.

19. The method according to claim 18 , further comprising using the secure update circuitry to compare the extended software measurement value to a predicted value therefor in the attempted software update.

20. The method according to claim 16 , wherein the at least one register comprises at least one non-volatile register.

21. The method according to claim 16 , wherein the attempted software update comprises at least one finger sensor driver software update.

22. The method according to claim 16 , further comprising a housing carrying the finger sensor and the host platform.