Commit b11674cf authored Jun 12, 2015 by Subbaraman Narayanamurthy Committed by Abhijeet Dharmapurikar Jun 17, 2015

power: qpnp-smbcharger: fix a potential race condition in accessing dc_psy



Commit abc711031653f5af30de63fdf41e878d9b4a09c1 ("power:
qpnp-smbcharger: Fix uninitialized access to dc_psy") tried
fixing an uninitialized access to dc_psy. However, there is
a race condition where dc_psy_type can get set just after
reading from device tree node but the dc_psy itself was not
registered at all.

This ends up in a system crash when the driver tries to call
power_supply_changed of dc_psy when it's not even registered.
Fix this by checking whether the dc_psy is registered before
calling power_supply_changed.

CRs-Fixed: 852821
Change-Id: Ic5f032107e0f5f1190b335e9d5de3e5497fd1e3c
Signed-off-by: Subbaraman Narayanamurthy <subbaram@codeaurora.org>
Signed-off-by: Abhijeet Dharmapurikar <adharmap@codeaurora.org>

parent 210b17b0

drivers/power/qpnp-smbcharger.c

+2 −2

Original line number	Diff line number	Diff line
		@@ -1322,7 +1322,7 @@ static int smbchg_dc_en(struct smbchg_chip *chip, bool enable,
		goto out;
		}

		if (chip->dc_psy_type != -EINVAL)
		if (chip->dc_psy_type != -EINVAL && chip->psy_registered)
		power_supply_changed(&chip->dc_psy);
		pr_smb(PR_STATUS, "dc charging %s, suspended = %02x\n",
		suspended == 0 ? "enabled"
		@@ -4291,7 +4291,7 @@ static irqreturn_t dcin_uv_handler(int irq, void *_chip)
		if (chip->dc_present != dc_present) {
		/* dc changed */
		chip->dc_present = dc_present;
		if (chip->psy_registered)
		if (chip->dc_psy_type != -EINVAL && chip->psy_registered)
		power_supply_changed(&chip->dc_psy);
		smbchg_charging_status_change(chip);
		smbchg_aicl_deglitch_wa_check(chip);