From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751451AbeFDTBO (ORCPT ); Mon, 4 Jun 2018 15:01:14 -0400 Received: from mx0a-001b2d01.pphosted.com ([148.163.156.1]:40308 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751411AbeFDTBM (ORCPT ); Mon, 4 Jun 2018 15:01:12 -0400 From: Eddie James To: linux-i2c@vger.kernel.org Cc: linux-kernel@vger.kernel.org, devicetree@vger.kernel.org, wsa@the-dreams.de, robh+dt@kernel.org, benh@kernel.crashing.org, joel@jms.id.au, mark.rutland@arm.com, gregkh@linuxfoundation.org, rdunlap@infradead.org, andy.shevchenko@gmail.com, Eddie James Subject: [PATCH v9 6/7] i2c: fsi: Add I2C master locking Date: Mon, 4 Jun 2018 14:00:49 -0500 X-Mailer: git-send-email 1.8.3.1 In-Reply-To: <1528138850-18259-1-git-send-email-eajames@linux.vnet.ibm.com> References: <1528138850-18259-1-git-send-email-eajames@linux.vnet.ibm.com> X-TM-AS-GCONF: 00 x-cbid: 18060419-0040-0000-0000-0000043B17C1 X-IBM-SpamModules-Scores: X-IBM-SpamModules-Versions: BY=3.00009129; HX=3.00000241; KW=3.00000007; PH=3.00000004; SC=3.00000265; SDB=6.01042302; UDB=6.00533708; IPR=6.00821432; MB=3.00021461; MTD=3.00000008; XFM=3.00000015; UTC=2018-06-04 19:01:09 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 18060419-0041-0000-0000-0000084117C9 Message-Id: <1528138850-18259-7-git-send-email-eajames@linux.vnet.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:,, definitions=2018-06-04_13:,, signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 priorityscore=1501 malwarescore=0 suspectscore=1 phishscore=0 bulkscore=0 spamscore=0 clxscore=1015 lowpriorityscore=0 mlxscore=0 impostorscore=0 mlxlogscore=999 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1805220000 definitions=main-1806040219 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Since there are many ports per master, each with it's own adapter and chardev, we need some locking to prevent transfers from changing the master state while other transfers are in progress. Signed-off-by: Eddie James --- drivers/i2c/busses/i2c-fsi.c | 16 ++++++++++++---- 1 file changed, 12 insertions(+), 4 deletions(-) diff --git a/drivers/i2c/busses/i2c-fsi.c b/drivers/i2c/busses/i2c-fsi.c index 4e5964e..6e6e2b1 100644 --- a/drivers/i2c/busses/i2c-fsi.c +++ b/drivers/i2c/busses/i2c-fsi.c @@ -21,6 +21,7 @@ #include #include #include +#include #include #include @@ -143,6 +144,7 @@ struct fsi_i2c_master { struct fsi_device *fsi; u8 fifo_size; struct list_head ports; + struct mutex lock; }; struct fsi_i2c_port { @@ -569,11 +571,14 @@ static int fsi_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int i, rc; unsigned long start_time; struct fsi_i2c_port *port = adap->algo_data; + struct fsi_i2c_master *master = port->master; struct i2c_msg *msg; + mutex_lock(&master->lock); + rc = fsi_i2c_set_port(port); if (rc) - return rc; + goto unlock; for (i = 0; i < num; i++) { msg = msgs + i; @@ -581,15 +586,17 @@ static int fsi_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, rc = fsi_i2c_start(port, msg, i == num - 1); if (rc) - return rc; + goto unlock; rc = fsi_i2c_wait(port, msg, adap->timeout - (jiffies - start_time)); if (rc) - return rc; + goto unlock; } - return 0; +unlock: + mutex_unlock(&master->lock); + return rc; } static u32 fsi_i2c_functionality(struct i2c_adapter *adap) @@ -615,6 +622,7 @@ static int fsi_i2c_probe(struct device *dev) if (!i2c) return -ENOMEM; + mutex_init(&i2c->lock); i2c->fsi = to_fsi_dev(dev); INIT_LIST_HEAD(&i2c->ports); -- 1.8.3.1