[PATCH 1/2] NFC: st95hf: initialize semaphore and mutex earlier

[Daniel Mack <daniel@zonque.org>]

'rm_lock' and 'exchange_lock' need to be ready before the IRQ handler has a
chance to fire.

This fixes the oops below.

[    1.040255] Internal error: Oops: 96000004 [#1] PREEMPT SMP
[...]
[    1.181564] Call trace:
[    1.188591] Exception stack(0xffff00000a473c40 to 0xffff00000a473d80)
[    1.190943] 3c40: ffff80003673b118 0000000000000000 ffff800036374380 0000000000000000
[    1.197542] 3c60: 0000000000000000 0000000000000000 00000000044b2ac5 0000000000000001
[    1.205354] 3c80: ffff800036374d60 ffff00000a473d70 0000000000000980 0000000000000000
[    1.213166] 3ca0: 0000000000000001 0000000000000000 000000000000004c 0000000000000033
[    1.217590] st95hf spi2.0: err: por seq failed for st95hf
[    1.228788] 3cc0: 0000000000000019 0000000000000001 0000000000000007 ffff80003673b118
[    1.234175] 3ce0: ffff800009f27000 0000000000000000 ffff80003673b1c8 ffff80003673b1b0
[    1.241986] 3d00: ffff0000080f0000 ffff800009f716a4 ffff00000894bb40 0000000000000000
[    1.249800] 3d20: 0000000000000000 ffff00000a473d80 ffff0000084268c0 ffff00000a473d80
[    1.257611] 3d40: ffff0000084268c4 0000000040000005 ffff00000a473d60 ffff0000080e5688
[    1.265424] 3d60: ffffffffffffffff ffff0000084268a4 ffff00000a473d80 ffff0000084268c4
[    1.273239] [<ffff0000084268c4>] st95hf_irq_thread_handler+0x44/0x3a0
[    1.281048] [<ffff0000080f00b0>] irq_thread_fn+0x28/0x68
[    1.287468] [<ffff0000080f035c>] irq_thread+0x10c/0x1a0
[    1.292850] [<ffff0000080c50bc>] kthread+0x12c/0x130
[    1.297799] [<ffff000008084b88>] ret_from_fork+0x10/0x18
[    1.303008] Code: aa1603e0 f9403675 940d010f aa1303e0 (f94066a1)
[    1.308307] ---[ end trace d058c1b88aad74d8 ]---

Signed-off-by: Daniel Mack <daniel@zonque.org>
---
 drivers/nfc/st95hf/core.c | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/drivers/nfc/st95hf/core.c b/drivers/nfc/st95hf/core.c
index 2b26f762fbc3..394bdc7b0cf2 100644
--- a/drivers/nfc/st95hf/core.c
+++ b/drivers/nfc/st95hf/core.c
@@ -1112,8 +1112,10 @@ static int st95hf_probe(struct spi_device *nfc_spi_dev)
 		}
 	}
 
+	sema_init(&st95context->exchange_lock, 1);
 	init_completion(&spicontext->done);
 	mutex_init(&spicontext->spi_lock);
+	mutex_init(&st95context->rm_lock);
 
 	/*
 	 * Store spicontext in spi device object for using it in
@@ -1197,9 +1199,6 @@ static int st95hf_probe(struct spi_device *nfc_spi_dev)
 	/* store st95context in nfc device object */
 	nfc_digital_set_drvdata(st95context->ddev, st95context);
 
-	sema_init(&st95context->exchange_lock, 1);
-	mutex_init(&st95context->rm_lock);
-
 	return ret;
 
 err_free_digital_device:
-- 
2.14.3