Adds a device tree parameter to set the open delay on the touchscreen
conversion steps. Increasing this parameter helps the touch accuracy on
some screens.
Signed-off-by: Michael Welling <[email protected]>
---
.../bindings/input/touchscreen/ti-tsc-adc.txt | 5 +++++
drivers/input/touchscreen/ti_am335x_tsc.c | 18 ++++++++++++++----
2 files changed, 19 insertions(+), 4 deletions(-)
diff --git a/Documentation/devicetree/bindings/input/touchscreen/ti-tsc-adc.txt b/Documentation/devicetree/bindings/input/touchscreen/ti-tsc-adc.txt
index b1163bf..cb11fda 100644
--- a/Documentation/devicetree/bindings/input/touchscreen/ti-tsc-adc.txt
+++ b/Documentation/devicetree/bindings/input/touchscreen/ti-tsc-adc.txt
@@ -41,6 +41,11 @@ Optional properties:
charge step, so this does in fact function as a
hardware knob for adjusting the amount of "settling
time".
+ ti,open-delay: Open delay applied to all touchscreen conversion steps.
+ The value corresponds to the number of ADC clock
+ cycles to wait after applying the step configuration
+ registers and before sending the start of ADC
+ conversion. Maximum value is 0x3FFFF.
- child "adc"
ti,chan-step-opendelay: List of open delays for each channel of
diff --git a/drivers/input/touchscreen/ti_am335x_tsc.c b/drivers/input/touchscreen/ti_am335x_tsc.c
index 191a1b8..37a9729 100644
--- a/drivers/input/touchscreen/ti_am335x_tsc.c
+++ b/drivers/input/touchscreen/ti_am335x_tsc.c
@@ -54,6 +54,7 @@ struct titsc {
u32 inp_xp, inp_xn, inp_yp, inp_yn;
u32 step_mask;
u32 charge_delay;
+ u32 open_delay;
};
static unsigned int titsc_readl(struct titsc *ts, unsigned int reg)
@@ -148,7 +149,7 @@ static void titsc_step_config(struct titsc *ts_dev)
end_step = first_step + tsc_steps;
for (i = end_step - ts_dev->coordinate_readouts; i < end_step; i++) {
titsc_writel(ts_dev, REG_STEPCONFIG(i), config);
- titsc_writel(ts_dev, REG_STEPDELAY(i), STEPCONFIG_OPENDLY);
+ titsc_writel(ts_dev, REG_STEPDELAY(i), ts_dev->open_delay);
}
config = 0;
@@ -172,7 +173,7 @@ static void titsc_step_config(struct titsc *ts_dev)
end_step = first_step + ts_dev->coordinate_readouts;
for (i = first_step; i < end_step; i++) {
titsc_writel(ts_dev, REG_STEPCONFIG(i), config);
- titsc_writel(ts_dev, REG_STEPDELAY(i), STEPCONFIG_OPENDLY);
+ titsc_writel(ts_dev, REG_STEPDELAY(i), ts_dev->open_delay);
}
/* Make CHARGECONFIG same as IDLECONFIG */
@@ -188,13 +189,13 @@ static void titsc_step_config(struct titsc *ts_dev)
STEPCONFIG_INP(ts_dev->inp_xp);
titsc_writel(ts_dev, REG_STEPCONFIG(end_step), config);
titsc_writel(ts_dev, REG_STEPDELAY(end_step),
- STEPCONFIG_OPENDLY);
+ ts_dev->open_delay);
end_step++;
config |= STEPCONFIG_INP(ts_dev->inp_yn);
titsc_writel(ts_dev, REG_STEPCONFIG(end_step), config);
titsc_writel(ts_dev, REG_STEPDELAY(end_step),
- STEPCONFIG_OPENDLY);
+ ts_dev->open_delay);
/* The steps end ... end - readouts * 2 + 2 and bit 0 for TS_Charge */
stepenable = 1;
@@ -392,6 +393,15 @@ static int titsc_parse_dt(struct platform_device *pdev,
dev_warn(&pdev->dev, "ti,charge-delay not specified\n");
}
+ err = of_property_read_u32(node, "ti,open-delay",
+ &ts_dev->open_delay);
+ /*
+ * If ti,open-delay value is not specified, then use
+ * STEPCONFIG_OPENDLY as the default value.
+ */
+ if (err < 0)
+ ts_dev->open_delay = STEPCONFIG_OPENDLY;
+
return of_property_read_u32_array(node, "ti,wire-config",
ts_dev->config_inp, ARRAY_SIZE(ts_dev->config_inp));
}
--
2.1.4
Hi Michael,
+ Dmitry
On 08/12/2015 12:15 AM, Michael Welling wrote:
> Adds a device tree parameter to set the open delay on the touchscreen
> conversion steps. Increasing this parameter helps the touch accuracy on
> some screens.
>
> Signed-off-by: Michael Welling <[email protected]>
> ---
> .../bindings/input/touchscreen/ti-tsc-adc.txt | 5 +++++
> drivers/input/touchscreen/ti_am335x_tsc.c | 18 ++++++++++++++----
> 2 files changed, 19 insertions(+), 4 deletions(-)
>
> diff --git a/Documentation/devicetree/bindings/input/touchscreen/ti-tsc-adc.txt b/Documentation/devicetree/bindings/input/touchscreen/ti-tsc-adc.txt
> index b1163bf..cb11fda 100644
> --- a/Documentation/devicetree/bindings/input/touchscreen/ti-tsc-adc.txt
> +++ b/Documentation/devicetree/bindings/input/touchscreen/ti-tsc-adc.txt
> @@ -41,6 +41,11 @@ Optional properties:
> charge step, so this does in fact function as a
> hardware knob for adjusting the amount of "settling
> time".
> + ti,open-delay: Open delay applied to all touchscreen conversion steps.
> + The value corresponds to the number of ADC clock
> + cycles to wait after applying the step configuration
> + registers and before sending the start of ADC
> + conversion. Maximum value is 0x3FFFF.
>
Since open-delay is per step, is it not better to allow specifying
open-delay per step like ti,chan-step-opendelay of adc? This will help
control open-delay for all the four wires.
> - child "adc"
> ti,chan-step-opendelay: List of open delays for each channel of
> diff --git a/drivers/input/touchscreen/ti_am335x_tsc.c b/drivers/input/touchscreen/ti_am335x_tsc.c
> index 191a1b8..37a9729 100644
> --- a/drivers/input/touchscreen/ti_am335x_tsc.c
> +++ b/drivers/input/touchscreen/ti_am335x_tsc.c
> @@ -54,6 +54,7 @@ struct titsc {
> u32 inp_xp, inp_xn, inp_yp, inp_yn;
> u32 step_mask;
> u32 charge_delay;
> + u32 open_delay;
> };
>
> static unsigned int titsc_readl(struct titsc *ts, unsigned int reg)
> @@ -148,7 +149,7 @@ static void titsc_step_config(struct titsc *ts_dev)
> end_step = first_step + tsc_steps;
> for (i = end_step - ts_dev->coordinate_readouts; i < end_step; i++) {
> titsc_writel(ts_dev, REG_STEPCONFIG(i), config);
> - titsc_writel(ts_dev, REG_STEPDELAY(i), STEPCONFIG_OPENDLY);
> + titsc_writel(ts_dev, REG_STEPDELAY(i), ts_dev->open_delay);
> }
>
> config = 0;
> @@ -172,7 +173,7 @@ static void titsc_step_config(struct titsc *ts_dev)
> end_step = first_step + ts_dev->coordinate_readouts;
> for (i = first_step; i < end_step; i++) {
> titsc_writel(ts_dev, REG_STEPCONFIG(i), config);
> - titsc_writel(ts_dev, REG_STEPDELAY(i), STEPCONFIG_OPENDLY);
> + titsc_writel(ts_dev, REG_STEPDELAY(i), ts_dev->open_delay);
> }
>
> /* Make CHARGECONFIG same as IDLECONFIG */
> @@ -188,13 +189,13 @@ static void titsc_step_config(struct titsc *ts_dev)
> STEPCONFIG_INP(ts_dev->inp_xp);
> titsc_writel(ts_dev, REG_STEPCONFIG(end_step), config);
> titsc_writel(ts_dev, REG_STEPDELAY(end_step),
> - STEPCONFIG_OPENDLY);
> + ts_dev->open_delay);
>
> end_step++;
> config |= STEPCONFIG_INP(ts_dev->inp_yn);
> titsc_writel(ts_dev, REG_STEPCONFIG(end_step), config);
> titsc_writel(ts_dev, REG_STEPDELAY(end_step),
> - STEPCONFIG_OPENDLY);
> + ts_dev->open_delay);
>
> /* The steps end ... end - readouts * 2 + 2 and bit 0 for TS_Charge */
> stepenable = 1;
> @@ -392,6 +393,15 @@ static int titsc_parse_dt(struct platform_device *pdev,
> dev_warn(&pdev->dev, "ti,charge-delay not specified\n");
> }
>
> + err = of_property_read_u32(node, "ti,open-delay",
> + &ts_dev->open_delay);
> + /*
> + * If ti,open-delay value is not specified, then use
> + * STEPCONFIG_OPENDLY as the default value.
> + */
> + if (err < 0)
> + ts_dev->open_delay = STEPCONFIG_OPENDLY;
> +
> return of_property_read_u32_array(node, "ti,wire-config",
> ts_dev->config_inp, ARRAY_SIZE(ts_dev->config_inp));
> }
>
--
Regards
Vignesh
On Wed, Aug 12, 2015 at 11:56:36AM +0530, Vignesh R wrote:
> Hi Michael,
>
> + Dmitry
>
> On 08/12/2015 12:15 AM, Michael Welling wrote:
> > Adds a device tree parameter to set the open delay on the touchscreen
> > conversion steps. Increasing this parameter helps the touch accuracy on
> > some screens.
> >
> > Signed-off-by: Michael Welling <[email protected]>
> > ---
> > .../bindings/input/touchscreen/ti-tsc-adc.txt | 5 +++++
> > drivers/input/touchscreen/ti_am335x_tsc.c | 18 ++++++++++++++----
> > 2 files changed, 19 insertions(+), 4 deletions(-)
> >
> > diff --git a/Documentation/devicetree/bindings/input/touchscreen/ti-tsc-adc.txt b/Documentation/devicetree/bindings/input/touchscreen/ti-tsc-adc.txt
> > index b1163bf..cb11fda 100644
> > --- a/Documentation/devicetree/bindings/input/touchscreen/ti-tsc-adc.txt
> > +++ b/Documentation/devicetree/bindings/input/touchscreen/ti-tsc-adc.txt
> > @@ -41,6 +41,11 @@ Optional properties:
> > charge step, so this does in fact function as a
> > hardware knob for adjusting the amount of "settling
> > time".
> > + ti,open-delay: Open delay applied to all touchscreen conversion steps.
> > + The value corresponds to the number of ADC clock
> > + cycles to wait after applying the step configuration
> > + registers and before sending the start of ADC
> > + conversion. Maximum value is 0x3FFFF.
> >
>
> Since open-delay is per step, is it not better to allow specifying
> open-delay per step like ti,chan-step-opendelay of adc? This will help
> control open-delay for all the four wires.
Do you see any reason why you would want a different delay for each step of
the conversion on the same touchscreen?
The user would need to know the number of steps what each of the steps do.
>
> > - child "adc"
> > ti,chan-step-opendelay: List of open delays for each channel of
> > diff --git a/drivers/input/touchscreen/ti_am335x_tsc.c b/drivers/input/touchscreen/ti_am335x_tsc.c
> > index 191a1b8..37a9729 100644
> > --- a/drivers/input/touchscreen/ti_am335x_tsc.c
> > +++ b/drivers/input/touchscreen/ti_am335x_tsc.c
> > @@ -54,6 +54,7 @@ struct titsc {
> > u32 inp_xp, inp_xn, inp_yp, inp_yn;
> > u32 step_mask;
> > u32 charge_delay;
> > + u32 open_delay;
> > };
> >
> > static unsigned int titsc_readl(struct titsc *ts, unsigned int reg)
> > @@ -148,7 +149,7 @@ static void titsc_step_config(struct titsc *ts_dev)
> > end_step = first_step + tsc_steps;
> > for (i = end_step - ts_dev->coordinate_readouts; i < end_step; i++) {
> > titsc_writel(ts_dev, REG_STEPCONFIG(i), config);
> > - titsc_writel(ts_dev, REG_STEPDELAY(i), STEPCONFIG_OPENDLY);
> > + titsc_writel(ts_dev, REG_STEPDELAY(i), ts_dev->open_delay);
> > }
> >
> > config = 0;
> > @@ -172,7 +173,7 @@ static void titsc_step_config(struct titsc *ts_dev)
> > end_step = first_step + ts_dev->coordinate_readouts;
> > for (i = first_step; i < end_step; i++) {
> > titsc_writel(ts_dev, REG_STEPCONFIG(i), config);
> > - titsc_writel(ts_dev, REG_STEPDELAY(i), STEPCONFIG_OPENDLY);
> > + titsc_writel(ts_dev, REG_STEPDELAY(i), ts_dev->open_delay);
> > }
> >
> > /* Make CHARGECONFIG same as IDLECONFIG */
> > @@ -188,13 +189,13 @@ static void titsc_step_config(struct titsc *ts_dev)
> > STEPCONFIG_INP(ts_dev->inp_xp);
> > titsc_writel(ts_dev, REG_STEPCONFIG(end_step), config);
> > titsc_writel(ts_dev, REG_STEPDELAY(end_step),
> > - STEPCONFIG_OPENDLY);
> > + ts_dev->open_delay);
> >
> > end_step++;
> > config |= STEPCONFIG_INP(ts_dev->inp_yn);
> > titsc_writel(ts_dev, REG_STEPCONFIG(end_step), config);
> > titsc_writel(ts_dev, REG_STEPDELAY(end_step),
> > - STEPCONFIG_OPENDLY);
> > + ts_dev->open_delay);
> >
> > /* The steps end ... end - readouts * 2 + 2 and bit 0 for TS_Charge */
> > stepenable = 1;
> > @@ -392,6 +393,15 @@ static int titsc_parse_dt(struct platform_device *pdev,
> > dev_warn(&pdev->dev, "ti,charge-delay not specified\n");
> > }
> >
> > + err = of_property_read_u32(node, "ti,open-delay",
> > + &ts_dev->open_delay);
> > + /*
> > + * If ti,open-delay value is not specified, then use
> > + * STEPCONFIG_OPENDLY as the default value.
> > + */
> > + if (err < 0)
> > + ts_dev->open_delay = STEPCONFIG_OPENDLY;
> > +
> > return of_property_read_u32_array(node, "ti,wire-config",
> > ts_dev->config_inp, ARRAY_SIZE(ts_dev->config_inp));
> > }
> >
>
> --
> Regards
> Vignesh
On Wed, Aug 12, 2015 at 01:44:22PM -0500, Michael Welling wrote:
> On Wed, Aug 12, 2015 at 11:56:36AM +0530, Vignesh R wrote:
> > Hi Michael,
> >
> > + Dmitry
> >
> > On 08/12/2015 12:15 AM, Michael Welling wrote:
> > > Adds a device tree parameter to set the open delay on the touchscreen
> > > conversion steps. Increasing this parameter helps the touch accuracy on
> > > some screens.
> > >
> > > Signed-off-by: Michael Welling <[email protected]>
> > > ---
> > > .../bindings/input/touchscreen/ti-tsc-adc.txt | 5 +++++
> > > drivers/input/touchscreen/ti_am335x_tsc.c | 18 ++++++++++++++----
> > > 2 files changed, 19 insertions(+), 4 deletions(-)
> > >
> > > diff --git a/Documentation/devicetree/bindings/input/touchscreen/ti-tsc-adc.txt b/Documentation/devicetree/bindings/input/touchscreen/ti-tsc-adc.txt
> > > index b1163bf..cb11fda 100644
> > > --- a/Documentation/devicetree/bindings/input/touchscreen/ti-tsc-adc.txt
> > > +++ b/Documentation/devicetree/bindings/input/touchscreen/ti-tsc-adc.txt
> > > @@ -41,6 +41,11 @@ Optional properties:
> > > charge step, so this does in fact function as a
> > > hardware knob for adjusting the amount of "settling
> > > time".
> > > + ti,open-delay: Open delay applied to all touchscreen conversion steps.
> > > + The value corresponds to the number of ADC clock
> > > + cycles to wait after applying the step configuration
> > > + registers and before sending the start of ADC
> > > + conversion. Maximum value is 0x3FFFF.
> > >
> >
> > Since open-delay is per step, is it not better to allow specifying
> > open-delay per step like ti,chan-step-opendelay of adc? This will help
> > control open-delay for all the four wires.
>
> Do you see any reason why you would want a different delay for each step of
> the conversion on the same touchscreen?
>
> The user would need to know the number of steps what each of the steps do.
>
Comments?
Any other concerns?
> >
> > > - child "adc"
> > > ti,chan-step-opendelay: List of open delays for each channel of
> > > diff --git a/drivers/input/touchscreen/ti_am335x_tsc.c b/drivers/input/touchscreen/ti_am335x_tsc.c
> > > index 191a1b8..37a9729 100644
> > > --- a/drivers/input/touchscreen/ti_am335x_tsc.c
> > > +++ b/drivers/input/touchscreen/ti_am335x_tsc.c
> > > @@ -54,6 +54,7 @@ struct titsc {
> > > u32 inp_xp, inp_xn, inp_yp, inp_yn;
> > > u32 step_mask;
> > > u32 charge_delay;
> > > + u32 open_delay;
> > > };
> > >
> > > static unsigned int titsc_readl(struct titsc *ts, unsigned int reg)
> > > @@ -148,7 +149,7 @@ static void titsc_step_config(struct titsc *ts_dev)
> > > end_step = first_step + tsc_steps;
> > > for (i = end_step - ts_dev->coordinate_readouts; i < end_step; i++) {
> > > titsc_writel(ts_dev, REG_STEPCONFIG(i), config);
> > > - titsc_writel(ts_dev, REG_STEPDELAY(i), STEPCONFIG_OPENDLY);
> > > + titsc_writel(ts_dev, REG_STEPDELAY(i), ts_dev->open_delay);
> > > }
> > >
> > > config = 0;
> > > @@ -172,7 +173,7 @@ static void titsc_step_config(struct titsc *ts_dev)
> > > end_step = first_step + ts_dev->coordinate_readouts;
> > > for (i = first_step; i < end_step; i++) {
> > > titsc_writel(ts_dev, REG_STEPCONFIG(i), config);
> > > - titsc_writel(ts_dev, REG_STEPDELAY(i), STEPCONFIG_OPENDLY);
> > > + titsc_writel(ts_dev, REG_STEPDELAY(i), ts_dev->open_delay);
> > > }
> > >
> > > /* Make CHARGECONFIG same as IDLECONFIG */
> > > @@ -188,13 +189,13 @@ static void titsc_step_config(struct titsc *ts_dev)
> > > STEPCONFIG_INP(ts_dev->inp_xp);
> > > titsc_writel(ts_dev, REG_STEPCONFIG(end_step), config);
> > > titsc_writel(ts_dev, REG_STEPDELAY(end_step),
> > > - STEPCONFIG_OPENDLY);
> > > + ts_dev->open_delay);
> > >
> > > end_step++;
> > > config |= STEPCONFIG_INP(ts_dev->inp_yn);
> > > titsc_writel(ts_dev, REG_STEPCONFIG(end_step), config);
> > > titsc_writel(ts_dev, REG_STEPDELAY(end_step),
> > > - STEPCONFIG_OPENDLY);
> > > + ts_dev->open_delay);
> > >
> > > /* The steps end ... end - readouts * 2 + 2 and bit 0 for TS_Charge */
> > > stepenable = 1;
> > > @@ -392,6 +393,15 @@ static int titsc_parse_dt(struct platform_device *pdev,
> > > dev_warn(&pdev->dev, "ti,charge-delay not specified\n");
> > > }
> > >
> > > + err = of_property_read_u32(node, "ti,open-delay",
> > > + &ts_dev->open_delay);
> > > + /*
> > > + * If ti,open-delay value is not specified, then use
> > > + * STEPCONFIG_OPENDLY as the default value.
> > > + */
> > > + if (err < 0)
> > > + ts_dev->open_delay = STEPCONFIG_OPENDLY;
> > > +
> > > return of_property_read_u32_array(node, "ti,wire-config",
> > > ts_dev->config_inp, ARRAY_SIZE(ts_dev->config_inp));
> > > }
> > >
> >
> > --
> > Regards
> > Vignesh
On 08/19/2015 11:38 PM, Michael Welling wrote:
> On Wed, Aug 12, 2015 at 01:44:22PM -0500, Michael Welling wrote:
>> On Wed, Aug 12, 2015 at 11:56:36AM +0530, Vignesh R wrote:
>>> Hi Michael,
>>>
>>> + Dmitry
>>>
>>> On 08/12/2015 12:15 AM, Michael Welling wrote:
>>>> Adds a device tree parameter to set the open delay on the touchscreen
>>>> conversion steps. Increasing this parameter helps the touch accuracy on
>>>> some screens.
>>>>
>>>> Signed-off-by: Michael Welling <[email protected]>
>>>> ---
>>>> .../bindings/input/touchscreen/ti-tsc-adc.txt | 5 +++++
>>>> drivers/input/touchscreen/ti_am335x_tsc.c | 18 ++++++++++++++----
>>>> 2 files changed, 19 insertions(+), 4 deletions(-)
>>>>
>>>> diff --git a/Documentation/devicetree/bindings/input/touchscreen/ti-tsc-adc.txt b/Documentation/devicetree/bindings/input/touchscreen/ti-tsc-adc.txt
>>>> index b1163bf..cb11fda 100644
>>>> --- a/Documentation/devicetree/bindings/input/touchscreen/ti-tsc-adc.txt
>>>> +++ b/Documentation/devicetree/bindings/input/touchscreen/ti-tsc-adc.txt
>>>> @@ -41,6 +41,11 @@ Optional properties:
>>>> charge step, so this does in fact function as a
>>>> hardware knob for adjusting the amount of "settling
>>>> time".
>>>> + ti,open-delay: Open delay applied to all touchscreen conversion steps.
>>>> + The value corresponds to the number of ADC clock
>>>> + cycles to wait after applying the step configuration
>>>> + registers and before sending the start of ADC
>>>> + conversion. Maximum value is 0x3FFFF.
>>>>
>>>
>>> Since open-delay is per step, is it not better to allow specifying
>>> open-delay per step like ti,chan-step-opendelay of adc? This will help
>>> control open-delay for all the four wires.
>>
>> Do you see any reason why you would want a different delay for each step of
>> the conversion on the same touchscreen?
Sorry for the delay,
I haven't seen different delays being used for different channels on
4-wire TSC ( not sure of 5-wire or 8 wire designs). Since this is DT
change, I just wanted to make sure more flexibility is provided.
>>
>> The user would need to know the number of steps what each of the steps do.
>>
What I was thinking was making open-delay configurable per channel (one
entry for X+, X-, Y+, Y-).
For example, for a 4-wire TSC:
ti,chan-open-delay = <0x30 0x100 0x20 0x10>; /* for X+, X-, Y+, Y- */
>>>
>>>> - child "adc"
>>>> ti,chan-step-opendelay: List of open delays for each channel of
>>>> diff --git a/drivers/input/touchscreen/ti_am335x_tsc.c b/drivers/input/touchscreen/ti_am335x_tsc.c
>>>> index 191a1b8..37a9729 100644
>>>> --- a/drivers/input/touchscreen/ti_am335x_tsc.c
>>>> +++ b/drivers/input/touchscreen/ti_am335x_tsc.c
>>>> @@ -54,6 +54,7 @@ struct titsc {
>>>> u32 inp_xp, inp_xn, inp_yp, inp_yn;
>>>> u32 step_mask;
>>>> u32 charge_delay;
>>>> + u32 open_delay;
>>>> };
>>>>
>>>> static unsigned int titsc_readl(struct titsc *ts, unsigned int reg)
>>>> @@ -148,7 +149,7 @@ static void titsc_step_config(struct titsc *ts_dev)
>>>> end_step = first_step + tsc_steps;
>>>> for (i = end_step - ts_dev->coordinate_readouts; i < end_step; i++) {
>>>> titsc_writel(ts_dev, REG_STEPCONFIG(i), config);
>>>> - titsc_writel(ts_dev, REG_STEPDELAY(i), STEPCONFIG_OPENDLY);
>>>> + titsc_writel(ts_dev, REG_STEPDELAY(i), ts_dev->open_delay);
>>>> }
>>>>
>>>> config = 0;
>>>> @@ -172,7 +173,7 @@ static void titsc_step_config(struct titsc *ts_dev)
>>>> end_step = first_step + ts_dev->coordinate_readouts;
>>>> for (i = first_step; i < end_step; i++) {
>>>> titsc_writel(ts_dev, REG_STEPCONFIG(i), config);
>>>> - titsc_writel(ts_dev, REG_STEPDELAY(i), STEPCONFIG_OPENDLY);
>>>> + titsc_writel(ts_dev, REG_STEPDELAY(i), ts_dev->open_delay);
>>>> }
>>>>
>>>> /* Make CHARGECONFIG same as IDLECONFIG */
>>>> @@ -188,13 +189,13 @@ static void titsc_step_config(struct titsc *ts_dev)
>>>> STEPCONFIG_INP(ts_dev->inp_xp);
>>>> titsc_writel(ts_dev, REG_STEPCONFIG(end_step), config);
>>>> titsc_writel(ts_dev, REG_STEPDELAY(end_step),
>>>> - STEPCONFIG_OPENDLY);
>>>> + ts_dev->open_delay);
>>>>
>>>> end_step++;
>>>> config |= STEPCONFIG_INP(ts_dev->inp_yn);
>>>> titsc_writel(ts_dev, REG_STEPCONFIG(end_step), config);
>>>> titsc_writel(ts_dev, REG_STEPDELAY(end_step),
>>>> - STEPCONFIG_OPENDLY);
>>>> + ts_dev->open_delay);
>>>>
>>>> /* The steps end ... end - readouts * 2 + 2 and bit 0 for TS_Charge */
>>>> stepenable = 1;
>>>> @@ -392,6 +393,15 @@ static int titsc_parse_dt(struct platform_device *pdev,
>>>> dev_warn(&pdev->dev, "ti,charge-delay not specified\n");
>>>> }
>>>>
>>>> + err = of_property_read_u32(node, "ti,open-delay",
>>>> + &ts_dev->open_delay);
>>>> + /*
>>>> + * If ti,open-delay value is not specified, then use
>>>> + * STEPCONFIG_OPENDLY as the default value.
>>>> + */
>>>> + if (err < 0)
>>>> + ts_dev->open_delay = STEPCONFIG_OPENDLY;
>>>> +
>>>> return of_property_read_u32_array(node, "ti,wire-config",
>>>> ts_dev->config_inp, ARRAY_SIZE(ts_dev->config_inp));
>>>> }
>>>>
>>>
>>> --
>>> Regards
>>> Vignesh
--
Regards
Vignesh
On Thu, Aug 20, 2015 at 05:41:30PM +0530, Vignesh R wrote:
>
>
> On 08/19/2015 11:38 PM, Michael Welling wrote:
> > On Wed, Aug 12, 2015 at 01:44:22PM -0500, Michael Welling wrote:
> >> On Wed, Aug 12, 2015 at 11:56:36AM +0530, Vignesh R wrote:
> >>> Hi Michael,
> >>>
> >>> + Dmitry
> >>>
> >>> On 08/12/2015 12:15 AM, Michael Welling wrote:
> >>>> Adds a device tree parameter to set the open delay on the touchscreen
> >>>> conversion steps. Increasing this parameter helps the touch accuracy on
> >>>> some screens.
> >>>>
> >>>> Signed-off-by: Michael Welling <[email protected]>
> >>>> ---
> >>>> .../bindings/input/touchscreen/ti-tsc-adc.txt | 5 +++++
> >>>> drivers/input/touchscreen/ti_am335x_tsc.c | 18 ++++++++++++++----
> >>>> 2 files changed, 19 insertions(+), 4 deletions(-)
> >>>>
> >>>> diff --git a/Documentation/devicetree/bindings/input/touchscreen/ti-tsc-adc.txt b/Documentation/devicetree/bindings/input/touchscreen/ti-tsc-adc.txt
> >>>> index b1163bf..cb11fda 100644
> >>>> --- a/Documentation/devicetree/bindings/input/touchscreen/ti-tsc-adc.txt
> >>>> +++ b/Documentation/devicetree/bindings/input/touchscreen/ti-tsc-adc.txt
> >>>> @@ -41,6 +41,11 @@ Optional properties:
> >>>> charge step, so this does in fact function as a
> >>>> hardware knob for adjusting the amount of "settling
> >>>> time".
> >>>> + ti,open-delay: Open delay applied to all touchscreen conversion steps.
> >>>> + The value corresponds to the number of ADC clock
> >>>> + cycles to wait after applying the step configuration
> >>>> + registers and before sending the start of ADC
> >>>> + conversion. Maximum value is 0x3FFFF.
> >>>>
> >>>
> >>> Since open-delay is per step, is it not better to allow specifying
> >>> open-delay per step like ti,chan-step-opendelay of adc? This will help
> >>> control open-delay for all the four wires.
> >>
> >> Do you see any reason why you would want a different delay for each step of
> >> the conversion on the same touchscreen?
>
>
> Sorry for the delay,
>
> I haven't seen different delays being used for different channels on
> 4-wire TSC ( not sure of 5-wire or 8 wire designs). Since this is DT
> change, I just wanted to make sure more flexibility is provided.
>
> >>
> >> The user would need to know the number of steps what each of the steps do.
> >>
>
>
> What I was thinking was making open-delay configurable per channel (one
> entry for X+, X-, Y+, Y-).
>
> For example, for a 4-wire TSC:
> ti,chan-open-delay = <0x30 0x100 0x20 0x10>; /* for X+, X-, Y+, Y- */
>
What about the readings for the pressure?
>
> >>>
> >>>> - child "adc"
> >>>> ti,chan-step-opendelay: List of open delays for each channel of
> >>>> diff --git a/drivers/input/touchscreen/ti_am335x_tsc.c b/drivers/input/touchscreen/ti_am335x_tsc.c
> >>>> index 191a1b8..37a9729 100644
> >>>> --- a/drivers/input/touchscreen/ti_am335x_tsc.c
> >>>> +++ b/drivers/input/touchscreen/ti_am335x_tsc.c
> >>>> @@ -54,6 +54,7 @@ struct titsc {
> >>>> u32 inp_xp, inp_xn, inp_yp, inp_yn;
> >>>> u32 step_mask;
> >>>> u32 charge_delay;
> >>>> + u32 open_delay;
> >>>> };
> >>>>
> >>>> static unsigned int titsc_readl(struct titsc *ts, unsigned int reg)
> >>>> @@ -148,7 +149,7 @@ static void titsc_step_config(struct titsc *ts_dev)
> >>>> end_step = first_step + tsc_steps;
> >>>> for (i = end_step - ts_dev->coordinate_readouts; i < end_step; i++) {
> >>>> titsc_writel(ts_dev, REG_STEPCONFIG(i), config);
> >>>> - titsc_writel(ts_dev, REG_STEPDELAY(i), STEPCONFIG_OPENDLY);
> >>>> + titsc_writel(ts_dev, REG_STEPDELAY(i), ts_dev->open_delay);
> >>>> }
> >>>>
> >>>> config = 0;
> >>>> @@ -172,7 +173,7 @@ static void titsc_step_config(struct titsc *ts_dev)
> >>>> end_step = first_step + ts_dev->coordinate_readouts;
> >>>> for (i = first_step; i < end_step; i++) {
> >>>> titsc_writel(ts_dev, REG_STEPCONFIG(i), config);
> >>>> - titsc_writel(ts_dev, REG_STEPDELAY(i), STEPCONFIG_OPENDLY);
> >>>> + titsc_writel(ts_dev, REG_STEPDELAY(i), ts_dev->open_delay);
> >>>> }
> >>>>
> >>>> /* Make CHARGECONFIG same as IDLECONFIG */
> >>>> @@ -188,13 +189,13 @@ static void titsc_step_config(struct titsc *ts_dev)
> >>>> STEPCONFIG_INP(ts_dev->inp_xp);
> >>>> titsc_writel(ts_dev, REG_STEPCONFIG(end_step), config);
> >>>> titsc_writel(ts_dev, REG_STEPDELAY(end_step),
> >>>> - STEPCONFIG_OPENDLY);
> >>>> + ts_dev->open_delay);
> >>>>
> >>>> end_step++;
> >>>> config |= STEPCONFIG_INP(ts_dev->inp_yn);
> >>>> titsc_writel(ts_dev, REG_STEPCONFIG(end_step), config);
> >>>> titsc_writel(ts_dev, REG_STEPDELAY(end_step),
> >>>> - STEPCONFIG_OPENDLY);
> >>>> + ts_dev->open_delay);
> >>>>
> >>>> /* The steps end ... end - readouts * 2 + 2 and bit 0 for TS_Charge */
> >>>> stepenable = 1;
> >>>> @@ -392,6 +393,15 @@ static int titsc_parse_dt(struct platform_device *pdev,
> >>>> dev_warn(&pdev->dev, "ti,charge-delay not specified\n");
> >>>> }
> >>>>
> >>>> + err = of_property_read_u32(node, "ti,open-delay",
> >>>> + &ts_dev->open_delay);
> >>>> + /*
> >>>> + * If ti,open-delay value is not specified, then use
> >>>> + * STEPCONFIG_OPENDLY as the default value.
> >>>> + */
> >>>> + if (err < 0)
> >>>> + ts_dev->open_delay = STEPCONFIG_OPENDLY;
> >>>> +
> >>>> return of_property_read_u32_array(node, "ti,wire-config",
> >>>> ts_dev->config_inp, ARRAY_SIZE(ts_dev->config_inp));
> >>>> }
> >>>>
> >>>
> >>> --
> >>> Regards
> >>> Vignesh
>
> --
> Regards
> Vignesh
On 08/21/2015 03:47 AM, Michael Welling wrote:
> On Thu, Aug 20, 2015 at 05:41:30PM +0530, Vignesh R wrote:
>>
>>
>> On 08/19/2015 11:38 PM, Michael Welling wrote:
>>> On Wed, Aug 12, 2015 at 01:44:22PM -0500, Michael Welling wrote:
>>>> On Wed, Aug 12, 2015 at 11:56:36AM +0530, Vignesh R wrote:
>>>>> Hi Michael,
>>>>>
>>>>> + Dmitry
>>>>>
>>>>> On 08/12/2015 12:15 AM, Michael Welling wrote:
>>>>>> Adds a device tree parameter to set the open delay on the touchscreen
>>>>>> conversion steps. Increasing this parameter helps the touch accuracy on
>>>>>> some screens.
>>>>>>
>>>>>> Signed-off-by: Michael Welling <[email protected]>
>>>>>> ---
>>>>>> .../bindings/input/touchscreen/ti-tsc-adc.txt | 5 +++++
>>>>>> drivers/input/touchscreen/ti_am335x_tsc.c | 18 ++++++++++++++----
>>>>>> 2 files changed, 19 insertions(+), 4 deletions(-)
>>>>>>
>>>>>> diff --git a/Documentation/devicetree/bindings/input/touchscreen/ti-tsc-adc.txt b/Documentation/devicetree/bindings/input/touchscreen/ti-tsc-adc.txt
>>>>>> index b1163bf..cb11fda 100644
>>>>>> --- a/Documentation/devicetree/bindings/input/touchscreen/ti-tsc-adc.txt
>>>>>> +++ b/Documentation/devicetree/bindings/input/touchscreen/ti-tsc-adc.txt
>>>>>> @@ -41,6 +41,11 @@ Optional properties:
>>>>>> charge step, so this does in fact function as a
>>>>>> hardware knob for adjusting the amount of "settling
>>>>>> time".
>>>>>> + ti,open-delay: Open delay applied to all touchscreen conversion steps.
>>>>>> + The value corresponds to the number of ADC clock
>>>>>> + cycles to wait after applying the step configuration
>>>>>> + registers and before sending the start of ADC
>>>>>> + conversion. Maximum value is 0x3FFFF.
>>>>>>
>>>>>
>>>>> Since open-delay is per step, is it not better to allow specifying
>>>>> open-delay per step like ti,chan-step-opendelay of adc? This will help
>>>>> control open-delay for all the four wires.
>>>>
>>>> Do you see any reason why you would want a different delay for each step of
>>>> the conversion on the same touchscreen?
>>
>>
>> Sorry for the delay,
>>
>> I haven't seen different delays being used for different channels on
>> 4-wire TSC ( not sure of 5-wire or 8 wire designs). Since this is DT
>> change, I just wanted to make sure more flexibility is provided.
>>
>>>>
>>>> The user would need to know the number of steps what each of the steps do.
>>>>
>>
>>
>> What I was thinking was making open-delay configurable per channel (one
>> entry for X+, X-, Y+, Y-).
>>
>> For example, for a 4-wire TSC:
>> ti,chan-open-delay = <0x30 0x100 0x20 0x10>; /* for X+, X-, Y+, Y- */
>>
>
> What about the readings for the pressure?
Sorry, I was confused with channels and co-ordinate readouts.
Each of X, Y and pressure(Z) readouts will correspond to certain tscadc
steps. So, what I have in mind is:
ti,open-delay = <0x30 0x100 0x20>; /* for X, Y, Z */
For Steps that represents X co-ordinate readouts set opendelay = 0x30.
For Steps that correspond to Y co-ordinate readouts set opendelay =
0x100 and similarly for 0x20 for Z.
This is will provide flexibility to configure open-delay independently
for X, Y and Z
--
Regards
Vignesh