Return-path: Received: from mga03.intel.com ([143.182.124.21]:17580 "EHLO mga03.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752943Ab2GFT7U (ORCPT ); Fri, 6 Jul 2012 15:59:20 -0400 From: Samuel Ortiz To: "John W. Linville" Cc: Lauro Ramos Venancio , Aloisio Almeida Jr , Ilan Elias , linux-wireless@vger.kernel.org, linux-nfc@lists.01.org, Eric Lapuyade , Samuel Ortiz Subject: [PATCH 11/33] NFC: nfc_targets_found() should accept zero target found Date: Fri, 6 Jul 2012 22:09:31 +0200 Message-Id: <1341605393-32056-12-git-send-email-sameo@linux.intel.com> (sfid-20120706_220533_916592_B478FE69) In-Reply-To: <1341605393-32056-1-git-send-email-sameo@linux.intel.com> References: <1341605393-32056-1-git-send-email-sameo@linux.intel.com> Sender: linux-wireless-owner@vger.kernel.org List-ID: From: Eric Lapuyade The semantics for a zero target found event is that the polling operation could not complete. Signed-off-by: Eric Lapuyade Signed-off-by: Samuel Ortiz --- net/nfc/core.c | 19 +++++++++++++------ 1 file changed, 13 insertions(+), 6 deletions(-) diff --git a/net/nfc/core.c b/net/nfc/core.c index 94ccf07..749ee48 100644 --- a/net/nfc/core.c +++ b/net/nfc/core.c @@ -560,6 +560,8 @@ EXPORT_SYMBOL(nfc_alloc_recv_skb); * The device driver must call this function when one or many nfc targets * are found. After calling this function, the device driver must stop * polling for targets. + * NOTE: This function can be called with targets=NULL and n_targets=0 to + * notify a driver error, meaning that the polling operation cannot complete. * IMPORTANT: this function must not be called from an atomic context. * In addition, it must also not be called from a context that would prevent * the NFC Core to call other nfc ops entry point concurrently. @@ -586,13 +588,18 @@ int nfc_targets_found(struct nfc_dev *dev, dev->targets_generation++; kfree(dev->targets); - dev->targets = kmemdup(targets, n_targets * sizeof(struct nfc_target), - GFP_ATOMIC); + dev->targets = NULL; - if (!dev->targets) { - dev->n_targets = 0; - device_unlock(&dev->dev); - return -ENOMEM; + if (targets) { + dev->targets = kmemdup(targets, + n_targets * sizeof(struct nfc_target), + GFP_ATOMIC); + + if (!dev->targets) { + dev->n_targets = 0; + device_unlock(&dev->dev); + return -ENOMEM; + } } dev->n_targets = n_targets; -- 1.7.10