From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Fu, Zhonghui" Subject: [PATCH] i2c/designware: enable i2c controller to suspend/resume asynchronously Date: Thu, 24 Dec 2015 22:30:42 +0800 Message-ID: <567C0192.2050601@linux.intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Return-path: Sender: linux-kernel-owner@vger.kernel.org To: Andy Shevchenko , jarkko.nikula@linux.intel.com, Mika Westerberg , Wolfram Sang Cc: linux-i2c@vger.kernel.org, "linux-kernel@vger.kernel.org" , srinivas.kowtal@intel.com List-Id: linux-i2c@vger.kernel.org Now, PM core supports asynchronous suspend/resume mode for devices during system suspend/resume, and the power state transition of one device may be completed in separate kernel thread. PM core ensures all power state transition dependency between devices. This patch enables designware i2c controllers to suspend/resume asynchronously. This will take advantage of multicore and improve system suspend/resume speed. After enabling all i2c devices, i2c adapters and i2c controllers on ASUS T100TA tablet, the system suspend-to-idle time is reduced to about 510ms from 750ms, and the system resume time is reduced to about 790ms from 900ms. Signed-off-by: Zhonghui Fu --- drivers/i2c/busses/i2c-designware-platdrv.c | 1 + 1 files changed, 1 insertions(+), 0 deletions(-) diff --git a/drivers/i2c/busses/i2c-designware-platdrv.c b/drivers/i2c/busses/i2c-designware-platdrv.c index 6b00061..395130b 100644 --- a/drivers/i2c/busses/i2c-designware-platdrv.c +++ b/drivers/i2c/busses/i2c-designware-platdrv.c @@ -230,6 +230,7 @@ static int dw_i2c_plat_probe(struct platform_device *pdev) } adap = &dev->adapter; + device_enable_async_suspend(&pdev->dev); adap->owner = THIS_MODULE; adap->class = I2C_CLASS_DEPRECATED; ACPI_COMPANION_SET(&adap->dev, ACPI_COMPANION(&pdev->dev)); -- 1.7.1