Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754285Ab3GJMzv (ORCPT ); Wed, 10 Jul 2013 08:55:51 -0400 Received: from mga03.intel.com ([143.182.124.21]:10903 "EHLO mga03.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752561Ab3GJMzt (ORCPT ); Wed, 10 Jul 2013 08:55:49 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.87,1036,1363158000"; d="scan'208";a="266389244" Date: Wed, 10 Jul 2013 16:01:16 +0300 From: Mika Westerberg To: linux-i2c@vger.kernel.org Cc: Wolfram Sang , Christian Ruppert , linux-kernel@vger.kernel.org Subject: Re: [PATCH 2/2] i2c-designware: configure *CNT values from ACPI Message-ID: <20130710130116.GC4898@intel.com> References: <1373283927-21677-1-git-send-email-mika.westerberg@linux.intel.com> <1373283927-21677-2-git-send-email-mika.westerberg@linux.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1373283927-21677-2-git-send-email-mika.westerberg@linux.intel.com> Organization: Intel Finland Oy - BIC 0357606-4 - Westendinkatu 7, 02160 Espoo User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3202 Lines: 77 On Mon, Jul 08, 2013 at 02:45:27PM +0300, Mika Westerberg wrote: > Some Intel LPSS I2C devices make the *CNT values available from ACPI > namespace in similar way than the SDA hold value. These values allow > platform/BIOS to specify the most accurate *CNT values for the device > driver to use. > > So change the ACPI part of the driver to use these values if they exists > and otherwise use the default method based solely on the input clock speed. > > Signed-off-by: Mika Westerberg > --- > This applies on top of following patch which is not yet in i2c tree: > > http://permalink.gmane.org/gmane.linux.drivers.i2c/15754 > > drivers/i2c/busses/i2c-designware-platdrv.c | 25 +++++++++++++++++++++---- > 1 file changed, 21 insertions(+), 4 deletions(-) > > diff --git a/drivers/i2c/busses/i2c-designware-platdrv.c b/drivers/i2c/busses/i2c-designware-platdrv.c > index c7cfdac..a1488df 100644 > --- a/drivers/i2c/busses/i2c-designware-platdrv.c > +++ b/drivers/i2c/busses/i2c-designware-platdrv.c > @@ -59,7 +59,6 @@ static int dw_i2c_acpi_configure(struct platform_device *pdev) > struct dw_i2c_dev *dev = platform_get_drvdata(pdev); > struct acpi_buffer buf = { ACPI_ALLOCATE_BUFFER }; > acpi_handle handle = ACPI_HANDLE(&pdev->dev); > - acpi_string name; > > if (!handle) > return -ENODEV; > @@ -68,14 +67,32 @@ static int dw_i2c_acpi_configure(struct platform_device *pdev) > dev->tx_fifo_depth = 32; > dev->rx_fifo_depth = 32; > > - name = dev->master_cfg & DW_IC_CON_SPEED_FAST ? "FMCN" : "SSCN"; > - if (ACPI_SUCCESS(acpi_evaluate_object(handle, name, NULL, &buf))) { > + /* Standard speed configuration */ > + if (ACPI_SUCCESS(acpi_evaluate_object(handle, "SSCN", NULL, &buf))) { > union acpi_object *obj = (union acpi_object *)buf.pointer; > > if (obj->type == ACPI_TYPE_PACKAGE && obj->package.count == 3) { > const union acpi_object *objs = obj->package.elements; > > - dev->sda_hold_time = (u32)objs[2].integer.value; > + dev->ss_hcnt = (u16)objs[0].integer.value; > + dev->ss_lcnt = (u16)objs[1].integer.value; > + if (!(dev->master_cfg & DW_IC_CON_SPEED_FAST)) > + dev->sda_hold_time = (u32)objs[2].integer.value; > + } > + > + kfree(buf.pointer); > + } > + /* Fast speed configuration */ > + if (ACPI_SUCCESS(acpi_evaluate_object(handle, "FMCN", NULL, &buf))) { There is a problem with the above as it reuses buf from the previous call. I'll post a new revision of the patches with this fixed. > + union acpi_object *obj = (union acpi_object *)buf.pointer; > + > + if (obj->type == ACPI_TYPE_PACKAGE && obj->package.count == 3) { > + const union acpi_object *objs = obj->package.elements; > + > + dev->fs_hcnt = (u16)objs[0].integer.value; > + dev->fs_lcnt = (u16)objs[1].integer.value; > + if (dev->master_cfg & DW_IC_CON_SPEED_FAST) > + dev->sda_hold_time = (u32)objs[2].integer.value; > } > > kfree(buf.pointer); > -- > 1.8.3.2 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/