Dmitry Osipenko 45f0d4b401 nfc: pn544: Fix occasional HW initialization failure ... [ Upstream commit c3331d2fe3 ] The PN544 driver checks the "enable" polarity during of driver's probe and it's doing that by turning ON and OFF NFC with different polarities until enabling succeeds. It takes some time for the hardware to power-down, and thus, to deassert the IRQ that is raised by turning ON the hardware. Since the delay after last power-down of the polarity-checking process is missed in the code, the interrupt may trigger immediately after installing the IRQ handler (right after the checking is done), which results in IRQ handler trying to touch the disabled HW and ends with marking NFC as 'DEAD' during of the driver's probe: pn544_hci_i2c 1-002a: NFC: nfc_en polarity : active high pn544_hci_i2c 1-002a: NFC: invalid len byte shdlc: llc_shdlc_recv_frame: NULL Frame -> link is dead This patch fixes the occasional NFC initialization failure on Nexus 7 device. Signed-off-by: Dmitry Osipenko <digetx@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>		2020-03-05 16:43:32 +01:00
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Kconfig	treewide: Add SPDX license identifier - Makefile/Kconfig	2019-05-21 10:50:46 +02:00
Makefile	treewide: Add SPDX license identifier - Makefile/Kconfig	2019-05-21 10:50:46 +02:00
i2c.c	nfc: pn544: Fix occasional HW initialization failure	2020-03-05 16:43:32 +01:00
mei.c	nfc/mei: convert to SPDX license tags	2019-03-28 02:07:54 +09:00
pn544.c	NFC: pn544: Adjust indentation in pn544_hci_check_presence	2020-02-11 04:35:45 -08:00
pn544.h	treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 13	2019-05-21 11:28:45 +02:00