From 7274496f2e1e799dbc260d7465e32077cb1a3fd6 Mon Sep 17 00:00:00 2001 From: Christophe Ricard Date: Sun, 25 Jan 2015 23:33:29 +0100 Subject: [PATCH] NFC: st21nfcb: Fix "NULL pointer dereference" possible error When the platform with CONFIG_ST21NFCB_I2C=y without any st21nfcb component physically connected a: "Unable to handle kernel NULL pointer dereference at virtual address" may show up at driver initialization phase. Signed-off-by: Christophe Ricard Signed-off-by: Samuel Ortiz --- drivers/nfc/st21nfcb/i2c.c | 18 +++++++++++------- 1 file changed, 11 insertions(+), 7 deletions(-) diff --git a/drivers/nfc/st21nfcb/i2c.c b/drivers/nfc/st21nfcb/i2c.c index b65847c62631..eb886932d972 100644 --- a/drivers/nfc/st21nfcb/i2c.c +++ b/drivers/nfc/st21nfcb/i2c.c @@ -199,7 +199,7 @@ static irqreturn_t st21nfcb_nci_irq_thread_fn(int irq, void *phy_id) struct sk_buff *skb = NULL; int r; - if (!phy || irq != phy->i2c_dev->irq) { + if (!phy || !phy->ndlc || irq != phy->i2c_dev->irq) { WARN_ON_ONCE(1); return IRQ_NONE; } @@ -343,18 +343,22 @@ static int st21nfcb_nci_i2c_probe(struct i2c_client *client, return -ENODEV; } + r = ndlc_probe(phy, &i2c_phy_ops, &client->dev, + ST21NFCB_FRAME_HEADROOM, ST21NFCB_FRAME_TAILROOM, + &phy->ndlc); + if (r < 0) { + nfc_err(&client->dev, "Unable to register ndlc layer\n"); + return r; + } + r = devm_request_threaded_irq(&client->dev, client->irq, NULL, st21nfcb_nci_irq_thread_fn, phy->irq_polarity | IRQF_ONESHOT, ST21NFCB_NCI_DRIVER_NAME, phy); - if (r < 0) { + if (r < 0) nfc_err(&client->dev, "Unable to register IRQ handler\n"); - return r; - } - return ndlc_probe(phy, &i2c_phy_ops, &client->dev, - ST21NFCB_FRAME_HEADROOM, ST21NFCB_FRAME_TAILROOM, - &phy->ndlc); + return r; } static int st21nfcb_nci_i2c_remove(struct i2c_client *client)