From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759697AbcDFHcb (ORCPT ); Wed, 6 Apr 2016 03:32:31 -0400 Received: from mx0a-0016f401.pphosted.com ([67.231.148.174]:26656 "EHLO mx0a-0016f401.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758870AbcDFHc2 (ORCPT ); Wed, 6 Apr 2016 03:32:28 -0400 From: Jisheng Zhang To: , , , , , , , , CC: , , , , Jisheng Zhang Subject: [PATCH] i2c: designware-platdrv: get fast/std speed scl high/low count from DT Date: Wed, 6 Apr 2016 15:28:00 +0800 Message-ID: <1459927680-5480-1-git-send-email-jszhang@marvell.com> X-Mailer: git-send-email 2.8.0.rc3 MIME-Version: 1.0 Content-Type: text/plain X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:,, definitions=2016-04-06_04:,, signatures=0 X-Proofpoint-Details: rule=outbound_notspam policy=outbound score=0 spamscore=0 suspectscore=0 malwarescore=0 phishscore=0 adultscore=0 bulkscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1601100000 definitions=main-1604060109 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Sometimes, it's convenient to define the scl's high/low count directly, e.g HW people would do some measurement then directly give out the optimum counts. Previously, we solved the sda falling time and scl falling time by i2c_dw_scl_hcnt() and i2c_dw_scl_lcnt(), then put them into dt, but what we really care isn't the sda/scl falling time. >>From another side, the dw_i2c_acpi_configure() on ACPI platform also get hcnt/lcnt values rather than the sda/scl falling time from ACPI method, we want similar feature for DT platforms. Signed-off-by: Jisheng Zhang --- Documentation/devicetree/bindings/i2c/i2c-designware.txt | 16 ++++++++++++++++ drivers/i2c/busses/i2c-designware-platdrv.c | 8 ++++++++ 2 files changed, 24 insertions(+) diff --git a/Documentation/devicetree/bindings/i2c/i2c-designware.txt b/Documentation/devicetree/bindings/i2c/i2c-designware.txt index fee26dc..05176fbf 100644 --- a/Documentation/devicetree/bindings/i2c/i2c-designware.txt +++ b/Documentation/devicetree/bindings/i2c/i2c-designware.txt @@ -20,6 +20,22 @@ Optional properties : - i2c-sda-falling-time-ns : should contain the SDA falling time in nanoseconds. This value which is by default 300ns is used to compute the tHIGH period. + - i2c-ss-scl-high-count : should contain the standard speed i2c clock SCL high + count. If defined, the i2c-scl-falling-time-ns and i2c-sda-falling-time-ns + will be ignored. + + - i2c-ss-scl-low-count : should contain the standard speed i2c clock SCL low + count. If defined, the i2c-scl-falling-time-ns and i2c-sda-falling-time-ns + will be ignored. + + - i2c-fs-scl-high-count : should contain the fast speed i2c clock SCL high + count. If defined, the i2c-scl-falling-time-ns and i2c-sda-falling-time-ns + will be ignored. + + - i2c-fs-scl-low-count : should contain the fast speed i2c clock SCL low + count. If defined, the i2c-scl-falling-time-ns and i2c-sda-falling-time-ns + will be ignored. + Example : i2c@f0000 { diff --git a/drivers/i2c/busses/i2c-designware-platdrv.c b/drivers/i2c/busses/i2c-designware-platdrv.c index d656657..8739a60 100644 --- a/drivers/i2c/busses/i2c-designware-platdrv.c +++ b/drivers/i2c/busses/i2c-designware-platdrv.c @@ -188,6 +188,14 @@ static int dw_i2c_plat_probe(struct platform_device *pdev) &dev->scl_falling_time); device_property_read_u32(&pdev->dev, "clock-frequency", &clk_freq); + device_property_read_u16(&pdev->dev, "i2c-ss-scl-high-count", + &dev->ss_hcnt); + device_property_read_u16(&pdev->dev, "i2c-ss-scl-low-count", + &dev->ss_lcnt); + device_property_read_u16(&pdev->dev, "i2c-fs-scl-high-count", + &dev->fs_hcnt); + device_property_read_u16(&pdev->dev, "i2c-fs-scl-low-count", + &dev->fs_lcnt); } if (has_acpi_companion(&pdev->dev)) -- 2.8.0.rc3