Dear Andy, On Thu, 7 Apr 2016 21:05:35 +0300 Andy Shevchenko wrote: > On Wed, Apr 6, 2016 at 10:28 AM, Jisheng Zhang <jszhang@xxxxxxxxxxx> wrote: > > 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. > > > > Instead of duplicating some words maybe better to explicitly define > two groups of parameters and one which supersedes the other. I'm sorry, I can't catch your meaning. Could you please kindly give more details? Or examples of "two groups of parameters" Thanks, Jisheng > > > Signed-off-by: Jisheng Zhang <jszhang@xxxxxxxxxxx> > > --- > > 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 > > > > > -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html