| Message ID | 1439318705-18601-1-git-send-email-mwelling@ieee.org |
|---|---|
| State | Under Review, archived |
| Headers | show |
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 <mwelling@ieee.org> > --- > .../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)); > } >
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 <mwelling@ieee.org> > > --- > > .../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 -- 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
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 <mwelling@ieee.org> > > > --- > > > .../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 -- 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
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 <mwelling@ieee.org> >>>> --- >>>> .../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
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 <mwelling@ieee.org> > >>>> --- > >>>> .../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 -- 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
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 <mwelling@ieee.org> >>>>>> --- >>>>>> .../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
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)); }
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 <mwelling@ieee.org> --- .../bindings/input/touchscreen/ti-tsc-adc.txt | 5 +++++ drivers/input/touchscreen/ti_am335x_tsc.c | 18 ++++++++++++++---- 2 files changed, 19 insertions(+), 4 deletions(-)