* [PATCH 1/2] i2c: designware: device tree bindings for i2c speed mode @ 2014-08-19 18:34 ` atull 0 siblings, 0 replies; 11+ messages in thread From: atull-yzvPICuk2ABMcg4IHK0kFoH6Mc4MB0Vx @ 2014-08-19 18:34 UTC (permalink / raw) To: wsa-z923LK4zBo2bacvFa/9K2g, baruch-NswTu9S1W3P6gbPvEgmw2w, mika.westerberg-VuQAYsv1563Yd54FQh9/CA Cc: grant.likely-QSEj5FYQhm4dnm+yROfE0A, robh+dt-DgEjT+Ai2ygdnm+yROfE0A, skuribay-e+AXbWqSrlAAvxtiuMwx3w, Romain.Baeriswyl-ux6zf3SgZrrQT0dZR+AlfA, rafael.j.wysocki-ral2JQCrhuEAvxtiuMwx3w, alan-VuQAYsv1563Yd54FQh9/CA, linux-i2c-u79uwXL29TY76Z2rM5mHXA, linux-kernel-u79uwXL29TY76Z2rM5mHXA, devicetree-u79uwXL29TY76Z2rM5mHXA, delicious.quinoa-Re5JQEeQqe8AvxtiuMwx3w, dinguyen-yzvPICuk2ABMcg4IHK0kFoH6Mc4MB0Vx, yvanderv-yzvPICuk2ABMcg4IHK0kFoH6Mc4MB0Vx, Alan Tull From: Alan Tull <atull-yzvPICuk2ABMcg4IHK0kFoH6Mc4MB0Vx@public.gmane.org> Add "speed-mode" Device Tree property to select between standard and fast i2c mode. Previously, driver was hardwired as fast mode. Default to fast mode if property is not present. Signed-off-by: Alan Tull <atull-yzvPICuk2ABMcg4IHK0kFoH6Mc4MB0Vx@public.gmane.org> --- .../devicetree/bindings/i2c/i2c-designware.txt | 3 +++ 1 file changed, 3 insertions(+) diff --git a/Documentation/devicetree/bindings/i2c/i2c-designware.txt b/Documentation/devicetree/bindings/i2c/i2c-designware.txt index 5199b0c..0e4cd21 100644 --- a/Documentation/devicetree/bindings/i2c/i2c-designware.txt +++ b/Documentation/devicetree/bindings/i2c/i2c-designware.txt @@ -9,6 +9,8 @@ Required properties : Recommended properties : - clock-frequency : desired I2C bus clock frequency in Hz. + - speed-mode : 0 = standard (0 - 100Kb/s) + : 1 = fast (<= 400Kb/s) <== default Optional properties : - i2c-sda-hold-time-ns : should contain the SDA hold time in nanoseconds. @@ -29,6 +31,7 @@ Example : reg = <0xf0000 0x1000>; interrupts = <11>; clock-frequency = <400000>; + speed-mode = <0>; }; i2c@1120000 { -- 1.7.9.5 -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html ^ permalink raw reply related [flat|nested] 11+ messages in thread
* [PATCH 1/2] i2c: designware: device tree bindings for i2c speed mode @ 2014-08-19 18:34 ` atull 0 siblings, 0 replies; 11+ messages in thread From: atull @ 2014-08-19 18:34 UTC (permalink / raw) To: wsa, baruch, mika.westerberg Cc: grant.likely, robh+dt, skuribay, Romain.Baeriswyl, rafael.j.wysocki, alan, linux-i2c, linux-kernel, devicetree, delicious.quinoa, dinguyen, yvanderv, Alan Tull From: Alan Tull <atull@opensource.altera.com> Add "speed-mode" Device Tree property to select between standard and fast i2c mode. Previously, driver was hardwired as fast mode. Default to fast mode if property is not present. Signed-off-by: Alan Tull <atull@opensource.altera.com> --- .../devicetree/bindings/i2c/i2c-designware.txt | 3 +++ 1 file changed, 3 insertions(+) diff --git a/Documentation/devicetree/bindings/i2c/i2c-designware.txt b/Documentation/devicetree/bindings/i2c/i2c-designware.txt index 5199b0c..0e4cd21 100644 --- a/Documentation/devicetree/bindings/i2c/i2c-designware.txt +++ b/Documentation/devicetree/bindings/i2c/i2c-designware.txt @@ -9,6 +9,8 @@ Required properties : Recommended properties : - clock-frequency : desired I2C bus clock frequency in Hz. + - speed-mode : 0 = standard (0 - 100Kb/s) + : 1 = fast (<= 400Kb/s) <== default Optional properties : - i2c-sda-hold-time-ns : should contain the SDA hold time in nanoseconds. @@ -29,6 +31,7 @@ Example : reg = <0xf0000 0x1000>; interrupts = <11>; clock-frequency = <400000>; + speed-mode = <0>; }; i2c@1120000 { -- 1.7.9.5 ^ permalink raw reply related [flat|nested] 11+ messages in thread
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* [PATCH 2/2] i2c: designware: add speed mode device tree setting 2014-08-19 18:34 ` atull @ 2014-08-19 18:34 ` atull -1 siblings, 0 replies; 11+ messages in thread From: atull-yzvPICuk2ABMcg4IHK0kFoH6Mc4MB0Vx @ 2014-08-19 18:34 UTC (permalink / raw) To: wsa-z923LK4zBo2bacvFa/9K2g, baruch-NswTu9S1W3P6gbPvEgmw2w, mika.westerberg-VuQAYsv1563Yd54FQh9/CA Cc: grant.likely-QSEj5FYQhm4dnm+yROfE0A, robh+dt-DgEjT+Ai2ygdnm+yROfE0A, skuribay-e+AXbWqSrlAAvxtiuMwx3w, Romain.Baeriswyl-ux6zf3SgZrrQT0dZR+AlfA, rafael.j.wysocki-ral2JQCrhuEAvxtiuMwx3w, alan-VuQAYsv1563Yd54FQh9/CA, linux-i2c-u79uwXL29TY76Z2rM5mHXA, linux-kernel-u79uwXL29TY76Z2rM5mHXA, devicetree-u79uwXL29TY76Z2rM5mHXA, delicious.quinoa-Re5JQEeQqe8AvxtiuMwx3w, dinguyen-yzvPICuk2ABMcg4IHK0kFoH6Mc4MB0Vx, yvanderv-yzvPICuk2ABMcg4IHK0kFoH6Mc4MB0Vx, Alan Tull From: Alan Tull <atull-yzvPICuk2ABMcg4IHK0kFoH6Mc4MB0Vx@public.gmane.org> Add "speed-mode" Device Tree property to select between standard and fast i2c mode. Previously, driver was hardwired as fast mode. Default to fast mode if property is not present. Signed-off-by: Alan Tull <atull-yzvPICuk2ABMcg4IHK0kFoH6Mc4MB0Vx@public.gmane.org> --- drivers/i2c/busses/i2c-designware-platdrv.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) diff --git a/drivers/i2c/busses/i2c-designware-platdrv.c b/drivers/i2c/busses/i2c-designware-platdrv.c index bc87733..3fdc775 100644 --- a/drivers/i2c/busses/i2c-designware-platdrv.c +++ b/drivers/i2c/busses/i2c-designware-platdrv.c @@ -122,7 +122,7 @@ static int dw_i2c_probe(struct platform_device *pdev) struct dw_i2c_dev *dev; struct i2c_adapter *adap; struct resource *mem; - int irq, r; + int irq, r, speed_prop, ret, speed = DW_IC_CON_SPEED_FAST; irq = platform_get_irq(pdev, 0); if (irq < 0) { @@ -167,6 +167,11 @@ static int dw_i2c_probe(struct platform_device *pdev) of_property_read_u32(pdev->dev.of_node, "i2c-scl-falling-time-ns", &dev->scl_falling_time); + + ret = of_property_read_u32(pdev->dev.of_node, + "speed-mode", &speed_prop); + if (!ret && (speed_prop == 0)) + speed = DW_IC_CON_SPEED_STD; } dev->functionality = @@ -177,7 +182,7 @@ static int dw_i2c_probe(struct platform_device *pdev) I2C_FUNC_SMBUS_WORD_DATA | I2C_FUNC_SMBUS_I2C_BLOCK; dev->master_cfg = DW_IC_CON_MASTER | DW_IC_CON_SLAVE_DISABLE | - DW_IC_CON_RESTART_EN | DW_IC_CON_SPEED_FAST; + DW_IC_CON_RESTART_EN | speed; /* Try first if we can configure the device from ACPI */ r = dw_i2c_acpi_configure(pdev); -- 1.7.9.5 ^ permalink raw reply related [flat|nested] 11+ messages in thread
* [PATCH 2/2] i2c: designware: add speed mode device tree setting @ 2014-08-19 18:34 ` atull 0 siblings, 0 replies; 11+ messages in thread From: atull @ 2014-08-19 18:34 UTC (permalink / raw) To: wsa, baruch, mika.westerberg Cc: grant.likely, robh+dt, skuribay, Romain.Baeriswyl, rafael.j.wysocki, alan, linux-i2c, linux-kernel, devicetree, delicious.quinoa, dinguyen, yvanderv, Alan Tull From: Alan Tull <atull@opensource.altera.com> Add "speed-mode" Device Tree property to select between standard and fast i2c mode. Previously, driver was hardwired as fast mode. Default to fast mode if property is not present. Signed-off-by: Alan Tull <atull@opensource.altera.com> --- drivers/i2c/busses/i2c-designware-platdrv.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) diff --git a/drivers/i2c/busses/i2c-designware-platdrv.c b/drivers/i2c/busses/i2c-designware-platdrv.c index bc87733..3fdc775 100644 --- a/drivers/i2c/busses/i2c-designware-platdrv.c +++ b/drivers/i2c/busses/i2c-designware-platdrv.c @@ -122,7 +122,7 @@ static int dw_i2c_probe(struct platform_device *pdev) struct dw_i2c_dev *dev; struct i2c_adapter *adap; struct resource *mem; - int irq, r; + int irq, r, speed_prop, ret, speed = DW_IC_CON_SPEED_FAST; irq = platform_get_irq(pdev, 0); if (irq < 0) { @@ -167,6 +167,11 @@ static int dw_i2c_probe(struct platform_device *pdev) of_property_read_u32(pdev->dev.of_node, "i2c-scl-falling-time-ns", &dev->scl_falling_time); + + ret = of_property_read_u32(pdev->dev.of_node, + "speed-mode", &speed_prop); + if (!ret && (speed_prop == 0)) + speed = DW_IC_CON_SPEED_STD; } dev->functionality = @@ -177,7 +182,7 @@ static int dw_i2c_probe(struct platform_device *pdev) I2C_FUNC_SMBUS_WORD_DATA | I2C_FUNC_SMBUS_I2C_BLOCK; dev->master_cfg = DW_IC_CON_MASTER | DW_IC_CON_SLAVE_DISABLE | - DW_IC_CON_RESTART_EN | DW_IC_CON_SPEED_FAST; + DW_IC_CON_RESTART_EN | speed; /* Try first if we can configure the device from ACPI */ r = dw_i2c_acpi_configure(pdev); -- 1.7.9.5 ^ permalink raw reply related [flat|nested] 11+ messages in thread
* Re: [PATCH 1/2] i2c: designware: device tree bindings for i2c speed mode 2014-08-19 18:34 ` atull @ 2014-08-19 19:15 ` Wolfram Sang -1 siblings, 0 replies; 11+ messages in thread From: Wolfram Sang @ 2014-08-19 19:15 UTC (permalink / raw) To: atull-yzvPICuk2ABMcg4IHK0kFoH6Mc4MB0Vx Cc: baruch-NswTu9S1W3P6gbPvEgmw2w, mika.westerberg-VuQAYsv1563Yd54FQh9/CA, grant.likely-QSEj5FYQhm4dnm+yROfE0A, robh+dt-DgEjT+Ai2ygdnm+yROfE0A, skuribay-e+AXbWqSrlAAvxtiuMwx3w, Romain.Baeriswyl-ux6zf3SgZrrQT0dZR+AlfA, rafael.j.wysocki-ral2JQCrhuEAvxtiuMwx3w, alan-VuQAYsv1563Yd54FQh9/CA, linux-i2c-u79uwXL29TY76Z2rM5mHXA, linux-kernel-u79uwXL29TY76Z2rM5mHXA, devicetree-u79uwXL29TY76Z2rM5mHXA, delicious.quinoa-Re5JQEeQqe8AvxtiuMwx3w, dinguyen-yzvPICuk2ABMcg4IHK0kFoH6Mc4MB0Vx, yvanderv-yzvPICuk2ABMcg4IHK0kFoH6Mc4MB0Vx [-- Attachment #1: Type: text/plain, Size: 1630 bytes --] On Tue, Aug 19, 2014 at 01:34:35PM -0500, atull-yzvPICuk2ABMcg4IHK0kFoH6Mc4MB0Vx@public.gmane.org wrote: > From: Alan Tull <atull-yzvPICuk2ABMcg4IHK0kFoH6Mc4MB0Vx@public.gmane.org> > > Add "speed-mode" Device Tree property to select between > standard and fast i2c mode. Previously, driver was hardwired > as fast mode. Default to fast mode if property is not > present. NACK. This should be deduced from the clock-frequency setting... > > Signed-off-by: Alan Tull <atull-yzvPICuk2ABMcg4IHK0kFoH6Mc4MB0Vx@public.gmane.org> > --- > .../devicetree/bindings/i2c/i2c-designware.txt | 3 +++ > 1 file changed, 3 insertions(+) > > diff --git a/Documentation/devicetree/bindings/i2c/i2c-designware.txt b/Documentation/devicetree/bindings/i2c/i2c-designware.txt > index 5199b0c..0e4cd21 100644 > --- a/Documentation/devicetree/bindings/i2c/i2c-designware.txt > +++ b/Documentation/devicetree/bindings/i2c/i2c-designware.txt > @@ -9,6 +9,8 @@ Required properties : > Recommended properties : > > - clock-frequency : desired I2C bus clock frequency in Hz. ... which is described here, but surprisingly not supported in the driver yet :( Check i2c-riic for an example. > + - speed-mode : 0 = standard (0 - 100Kb/s) > + : 1 = fast (<= 400Kb/s) <== default > > Optional properties : > - i2c-sda-hold-time-ns : should contain the SDA hold time in nanoseconds. > @@ -29,6 +31,7 @@ Example : > reg = <0xf0000 0x1000>; > interrupts = <11>; > clock-frequency = <400000>; > + speed-mode = <0>; > }; > > i2c@1120000 { > -- > 1.7.9.5 > [-- Attachment #2: Digital signature --] [-- Type: application/pgp-signature, Size: 819 bytes --] ^ permalink raw reply [flat|nested] 11+ messages in thread
* Re: [PATCH 1/2] i2c: designware: device tree bindings for i2c speed mode @ 2014-08-19 19:15 ` Wolfram Sang 0 siblings, 0 replies; 11+ messages in thread From: Wolfram Sang @ 2014-08-19 19:15 UTC (permalink / raw) To: atull Cc: baruch, mika.westerberg, grant.likely, robh+dt, skuribay, Romain.Baeriswyl, rafael.j.wysocki, alan, linux-i2c, linux-kernel, devicetree, delicious.quinoa, dinguyen, yvanderv [-- Attachment #1: Type: text/plain, Size: 1546 bytes --] On Tue, Aug 19, 2014 at 01:34:35PM -0500, atull@opensource.altera.com wrote: > From: Alan Tull <atull@opensource.altera.com> > > Add "speed-mode" Device Tree property to select between > standard and fast i2c mode. Previously, driver was hardwired > as fast mode. Default to fast mode if property is not > present. NACK. This should be deduced from the clock-frequency setting... > > Signed-off-by: Alan Tull <atull@opensource.altera.com> > --- > .../devicetree/bindings/i2c/i2c-designware.txt | 3 +++ > 1 file changed, 3 insertions(+) > > diff --git a/Documentation/devicetree/bindings/i2c/i2c-designware.txt b/Documentation/devicetree/bindings/i2c/i2c-designware.txt > index 5199b0c..0e4cd21 100644 > --- a/Documentation/devicetree/bindings/i2c/i2c-designware.txt > +++ b/Documentation/devicetree/bindings/i2c/i2c-designware.txt > @@ -9,6 +9,8 @@ Required properties : > Recommended properties : > > - clock-frequency : desired I2C bus clock frequency in Hz. ... which is described here, but surprisingly not supported in the driver yet :( Check i2c-riic for an example. > + - speed-mode : 0 = standard (0 - 100Kb/s) > + : 1 = fast (<= 400Kb/s) <== default > > Optional properties : > - i2c-sda-hold-time-ns : should contain the SDA hold time in nanoseconds. > @@ -29,6 +31,7 @@ Example : > reg = <0xf0000 0x1000>; > interrupts = <11>; > clock-frequency = <400000>; > + speed-mode = <0>; > }; > > i2c@1120000 { > -- > 1.7.9.5 > [-- Attachment #2: Digital signature --] [-- Type: application/pgp-signature, Size: 819 bytes --] ^ permalink raw reply [flat|nested] 11+ messages in thread
* Re: [PATCH 1/2] i2c: designware: device tree bindings for i2c speed mode 2014-08-19 19:15 ` Wolfram Sang @ 2014-08-19 20:24 ` atull -1 siblings, 0 replies; 11+ messages in thread From: atull @ 2014-08-19 20:24 UTC (permalink / raw) To: Wolfram Sang Cc: baruch-NswTu9S1W3P6gbPvEgmw2w, mika.westerberg-VuQAYsv1563Yd54FQh9/CA, grant.likely-QSEj5FYQhm4dnm+yROfE0A, robh+dt-DgEjT+Ai2ygdnm+yROfE0A, skuribay-e+AXbWqSrlAAvxtiuMwx3w, Romain.Baeriswyl-ux6zf3SgZrrQT0dZR+AlfA, rafael.j.wysocki-ral2JQCrhuEAvxtiuMwx3w, alan-VuQAYsv1563Yd54FQh9/CA, linux-i2c-u79uwXL29TY76Z2rM5mHXA, linux-kernel-u79uwXL29TY76Z2rM5mHXA, devicetree-u79uwXL29TY76Z2rM5mHXA, delicious.quinoa-Re5JQEeQqe8AvxtiuMwx3w, dinguyen-yzvPICuk2ABMcg4IHK0kFoH6Mc4MB0Vx, yvanderv-yzvPICuk2ABMcg4IHK0kFoH6Mc4MB0Vx On Tue, 19 Aug 2014, Wolfram Sang wrote: > On Tue, Aug 19, 2014 at 01:34:35PM -0500, atull-yzvPICuk2ABMcg4IHK0kFoH6Mc4MB0Vx@public.gmane.org wrote: > > From: Alan Tull <atull-yzvPICuk2ABMcg4IHK0kFoH6Mc4MB0Vx@public.gmane.org> > > > > Add "speed-mode" Device Tree property to select between > > standard and fast i2c mode. Previously, driver was hardwired > > as fast mode. Default to fast mode if property is not > > present. > > NACK. This should be deduced from the clock-frequency setting... I just sent out a new patch that looks at the clock-frequency setting. Alan ^ permalink raw reply [flat|nested] 11+ messages in thread
* Re: [PATCH 1/2] i2c: designware: device tree bindings for i2c speed mode @ 2014-08-19 20:24 ` atull 0 siblings, 0 replies; 11+ messages in thread From: atull @ 2014-08-19 20:24 UTC (permalink / raw) To: Wolfram Sang Cc: baruch, mika.westerberg, grant.likely, robh+dt, skuribay, Romain.Baeriswyl, rafael.j.wysocki, alan, linux-i2c, linux-kernel, devicetree, delicious.quinoa, dinguyen, yvanderv On Tue, 19 Aug 2014, Wolfram Sang wrote: > On Tue, Aug 19, 2014 at 01:34:35PM -0500, atull@opensource.altera.com wrote: > > From: Alan Tull <atull@opensource.altera.com> > > > > Add "speed-mode" Device Tree property to select between > > standard and fast i2c mode. Previously, driver was hardwired > > as fast mode. Default to fast mode if property is not > > present. > > NACK. This should be deduced from the clock-frequency setting... I just sent out a new patch that looks at the clock-frequency setting. Alan ^ permalink raw reply [flat|nested] 11+ messages in thread
* Re: [PATCH 1/2] i2c: designware: device tree bindings for i2c speed mode 2014-08-19 18:34 ` atull (?) (?) @ 2014-08-20 9:34 ` Mark Rutland 2014-08-20 9:36 ` Mark Rutland -1 siblings, 1 reply; 11+ messages in thread From: Mark Rutland @ 2014-08-20 9:34 UTC (permalink / raw) To: atull@opensource.altera.com Cc: wsa@the-dreams.de, baruch@tkos.co.il, mika.westerberg@linux.intel.com, grant.likely@linaro.org, robh+dt@kernel.org, skuribay@pobox.com, Romain.Baeriswyl@abilis.com, rafael.j.wysocki@intel.com, alan@linux.intel.com, linux-i2c@vger.kernel.org, linux-kernel@vger.kernel.org, devicetree@vger.kernel.org, delicious.quinoa@gmail.com, dinguyen@opensource.altera.com, yvanderv@opensource.altera.com On Tue, Aug 19, 2014 at 07:34:35PM +0100, atull@opensource.altera.com wrote: > From: Alan Tull <atull@opensource.altera.com> > > Add "speed-mode" Device Tree property to select between > standard and fast i2c mode. Previously, driver was hardwired > as fast mode. Default to fast mode if property is not > present. > > Signed-off-by: Alan Tull <atull@opensource.altera.com> > --- > .../devicetree/bindings/i2c/i2c-designware.txt | 3 +++ > 1 file changed, 3 insertions(+) > > diff --git a/Documentation/devicetree/bindings/i2c/i2c-designware.txt b/Documentation/devicetree/bindings/i2c/i2c-designware.txt > index 5199b0c..0e4cd21 100644 > --- a/Documentation/devicetree/bindings/i2c/i2c-designware.txt > +++ b/Documentation/devicetree/bindings/i2c/i2c-designware.txt > @@ -9,6 +9,8 @@ Required properties : > Recommended properties : > > - clock-frequency : desired I2C bus clock frequency in Hz. > + - speed-mode : 0 = standard (0 - 100Kb/s) > + : 1 = fast (<= 400Kb/s) <== default This is a bit opaque. Is this a limit on the max bit-rate the device should operate at? Why not just have an optional boolean property to limit to standard speed? Thanks, Mark. > > Optional properties : > - i2c-sda-hold-time-ns : should contain the SDA hold time in nanoseconds. > @@ -29,6 +31,7 @@ Example : > reg = <0xf0000 0x1000>; > interrupts = <11>; > clock-frequency = <400000>; > + speed-mode = <0>; > }; > > i2c@1120000 { > -- > 1.7.9.5 > > -- > To unsubscribe from this list: send the line "unsubscribe devicetree" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > ^ permalink raw reply [flat|nested] 11+ messages in thread
* Re: [PATCH 1/2] i2c: designware: device tree bindings for i2c speed mode 2014-08-20 9:34 ` Mark Rutland @ 2014-08-20 9:36 ` Mark Rutland 0 siblings, 0 replies; 11+ messages in thread From: Mark Rutland @ 2014-08-20 9:36 UTC (permalink / raw) To: atull-yzvPICuk2ABMcg4IHK0kFoH6Mc4MB0Vx@public.gmane.org Cc: wsa-z923LK4zBo2bacvFa/9K2g@public.gmane.org, baruch-NswTu9S1W3P6gbPvEgmw2w@public.gmane.org, mika.westerberg-VuQAYsv1563Yd54FQh9/CA@public.gmane.org, grant.likely-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org, robh+dt-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org, skuribay-e+AXbWqSrlAAvxtiuMwx3w@public.gmane.org, Romain.Baeriswyl-ux6zf3SgZrrQT0dZR+AlfA@public.gmane.org, rafael.j.wysocki-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org, alan-VuQAYsv1563Yd54FQh9/CA@public.gmane.org, linux-i2c-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, delicious.quinoa-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org, dinguyen-yzvPICuk2ABMcg4IHK0kFoH6Mc4MB0Vx@public.gmane.org, yvanderv-yzvPICuk2ABMcg4IHK0kFoH6Mc4MB0Vx@public.gmane.org On Wed, Aug 20, 2014 at 10:34:59AM +0100, Mark Rutland wrote: > On Tue, Aug 19, 2014 at 07:34:35PM +0100, atull-yzvPICuk2ABMcg4IHK0kFoH6Mc4MB0Vx@public.gmane.org wrote: > > From: Alan Tull <atull-yzvPICuk2ABMcg4IHK0kFoH6Mc4MB0Vx@public.gmane.org> > > > > Add "speed-mode" Device Tree property to select between > > standard and fast i2c mode. Previously, driver was hardwired > > as fast mode. Default to fast mode if property is not > > present. > > > > Signed-off-by: Alan Tull <atull-yzvPICuk2ABMcg4IHK0kFoH6Mc4MB0Vx@public.gmane.org> > > --- > > .../devicetree/bindings/i2c/i2c-designware.txt | 3 +++ > > 1 file changed, 3 insertions(+) > > > > diff --git a/Documentation/devicetree/bindings/i2c/i2c-designware.txt b/Documentation/devicetree/bindings/i2c/i2c-designware.txt > > index 5199b0c..0e4cd21 100644 > > --- a/Documentation/devicetree/bindings/i2c/i2c-designware.txt > > +++ b/Documentation/devicetree/bindings/i2c/i2c-designware.txt > > @@ -9,6 +9,8 @@ Required properties : > > Recommended properties : > > > > - clock-frequency : desired I2C bus clock frequency in Hz. > > + - speed-mode : 0 = standard (0 - 100Kb/s) > > + : 1 = fast (<= 400Kb/s) <== default > > This is a bit opaque. > > Is this a limit on the max bit-rate the device should operate at? > > Why not just have an optional boolean property to limit to standard > speed? I see there's a new patch doing this based on clock-frequency, so feel free to ignore this. Mark. ^ permalink raw reply [flat|nested] 11+ messages in thread
* Re: [PATCH 1/2] i2c: designware: device tree bindings for i2c speed mode @ 2014-08-20 9:36 ` Mark Rutland 0 siblings, 0 replies; 11+ messages in thread From: Mark Rutland @ 2014-08-20 9:36 UTC (permalink / raw) To: atull@opensource.altera.com Cc: wsa@the-dreams.de, baruch@tkos.co.il, mika.westerberg@linux.intel.com, grant.likely@linaro.org, robh+dt@kernel.org, skuribay@pobox.com, Romain.Baeriswyl@abilis.com, rafael.j.wysocki@intel.com, alan@linux.intel.com, linux-i2c@vger.kernel.org, linux-kernel@vger.kernel.org, devicetree@vger.kernel.org, delicious.quinoa@gmail.com, dinguyen@opensource.altera.com, yvanderv@opensource.altera.com On Wed, Aug 20, 2014 at 10:34:59AM +0100, Mark Rutland wrote: > On Tue, Aug 19, 2014 at 07:34:35PM +0100, atull@opensource.altera.com wrote: > > From: Alan Tull <atull@opensource.altera.com> > > > > Add "speed-mode" Device Tree property to select between > > standard and fast i2c mode. Previously, driver was hardwired > > as fast mode. Default to fast mode if property is not > > present. > > > > Signed-off-by: Alan Tull <atull@opensource.altera.com> > > --- > > .../devicetree/bindings/i2c/i2c-designware.txt | 3 +++ > > 1 file changed, 3 insertions(+) > > > > diff --git a/Documentation/devicetree/bindings/i2c/i2c-designware.txt b/Documentation/devicetree/bindings/i2c/i2c-designware.txt > > index 5199b0c..0e4cd21 100644 > > --- a/Documentation/devicetree/bindings/i2c/i2c-designware.txt > > +++ b/Documentation/devicetree/bindings/i2c/i2c-designware.txt > > @@ -9,6 +9,8 @@ Required properties : > > Recommended properties : > > > > - clock-frequency : desired I2C bus clock frequency in Hz. > > + - speed-mode : 0 = standard (0 - 100Kb/s) > > + : 1 = fast (<= 400Kb/s) <== default > > This is a bit opaque. > > Is this a limit on the max bit-rate the device should operate at? > > Why not just have an optional boolean property to limit to standard > speed? I see there's a new patch doing this based on clock-frequency, so feel free to ignore this. Mark. ^ permalink raw reply [flat|nested] 11+ messages in thread
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2014-08-19 18:34 [PATCH 1/2] i2c: designware: device tree bindings for i2c speed mode atull-yzvPICuk2ABMcg4IHK0kFoH6Mc4MB0Vx
2014-08-19 18:34 ` atull
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2014-08-19 18:34 ` [PATCH 2/2] i2c: designware: add speed mode device tree setting atull-yzvPICuk2ABMcg4IHK0kFoH6Mc4MB0Vx
2014-08-19 18:34 ` atull
2014-08-19 19:15 ` [PATCH 1/2] i2c: designware: device tree bindings for i2c speed mode Wolfram Sang
2014-08-19 19:15 ` Wolfram Sang
2014-08-19 20:24 ` atull
2014-08-19 20:24 ` atull
2014-08-20 9:34 ` Mark Rutland
2014-08-20 9:36 ` Mark Rutland
2014-08-20 9:36 ` Mark Rutland
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