On Monday 03 November 2014 08:35 PM, Lee Jones wrote: > On Mon, 27 Oct 2014, Vignesh R wrote: >> From: Brad Griffis <[email protected]> >> >> TSC interrupt handler had udelay to avoid reporting of false pen-up >> interrupt to user space. This patch implements workaround suggesting in >> Advisory 1.0.31 of silicon errata for am335x, thus eliminating udelay >> and touchscreen lag. This also improves performance of touchscreen and >> eliminates sudden jump of cursor at touch release. >> >> IDLECONFIG and CHARGECONFIG registers are to be configured >> with same values in order to eliminate false pen-up events. This >> workaround may result in false pen-down to be detected, hence considerable >> charge step delay needs to be added. The charge delay is set to 0xB000 >> (in terms of ADC clock cycles) by default. >> >> TSC steps are disabled at the end of every sampling cycle and EOS bit is >> set. Once the EOS bit is set, the TSC steps need to be re-enabled to begin >> next sampling cycle. >> >> In one shot mode, sequencer automatically disables all enabled steps at >> the end of each cycle. (both ADC steps and TSC steps) Hence these steps >> need not be saved in reg_se_cache for clearing these steps at a later >> stage. >> >> Signed-off-by: Brad Griffis <[email protected]> >> [[email protected]: Ported patch from v3.12 to v3.18rc2] >> Signed-off-by: Vignesh R <[email protected]> >> --- >> drivers/input/touchscreen/ti_am335x_tsc.c | 56 >> ++++++++++++------------------- >> drivers/mfd/ti_am335x_tscadc.c | 7 ++-- >> include/linux/mfd/ti_am335x_tscadc.h | 4 ++- >> 3 files changed, 30 insertions(+), 37 deletions(-) > > [...] > >> diff --git a/drivers/mfd/ti_am335x_tscadc.c b/drivers/mfd/ti_am335x_tscadc.c >> index d877e777cce6..94ef8992f46b 100644 >> --- a/drivers/mfd/ti_am335x_tscadc.c >> +++ b/drivers/mfd/ti_am335x_tscadc.c >> @@ -86,8 +86,12 @@ static void am335x_tscadc_need_adc(struct ti_tscadc_dev >> *tsadc) >> spin_lock_irq(&tsadc->reg_lock); >> finish_wait(&tsadc->reg_se_wait, &wait); >> >> + /* >> + * Sequencer should either be idle or >> + * busy applying the charge step. >> + */ >> reg = tscadc_readl(tsadc, REG_ADCFSM); >> - WARN_ON(reg & SEQ_STATUS); >> + WARN_ON(reg & SEQ_STATUS & (!CHARGE_STEP)); >> tsadc->adc_waiting = false; >> } >> tsadc->adc_in_use = true; >> @@ -96,7 +100,6 @@ static void am335x_tscadc_need_adc(struct ti_tscadc_dev >> *tsadc) >> void am335x_tsc_se_set_once(struct ti_tscadc_dev *tsadc, u32 val) >> { >> spin_lock_irq(&tsadc->reg_lock); >> - tsadc->reg_se_cache |= val; >> am335x_tscadc_need_adc(tsadc); >> >> tscadc_writel(tsadc, REG_SE, val); > > I believe all of these changes can, and therefor should live in a > separate patch.
I will split this patch accordingly. > >> diff --git a/include/linux/mfd/ti_am335x_tscadc.h >> b/include/linux/mfd/ti_am335x_tscadc.h >> index e2e70053470e..fcce182e4a35 100644 >> --- a/include/linux/mfd/ti_am335x_tscadc.h >> +++ b/include/linux/mfd/ti_am335x_tscadc.h >> @@ -52,6 +52,7 @@ >> >> /* IRQ enable */ >> #define IRQENB_HW_PEN BIT(0) >> +#define IRQENB_EOS BIT(1) >> #define IRQENB_FIFO0THRES BIT(2) >> #define IRQENB_FIFO0OVRRUN BIT(3) >> #define IRQENB_FIFO0UNDRFLW BIT(4) >> @@ -107,7 +108,7 @@ >> /* Charge delay */ >> #define CHARGEDLY_OPEN_MASK (0x3FFFF << 0) >> #define CHARGEDLY_OPEN(val) ((val) << 0) >> -#define CHARGEDLY_OPENDLY CHARGEDLY_OPEN(1) >> +#define CHARGEDLY_OPENDLY CHARGEDLY_OPEN(0xB000) >> >> /* Control register */ >> #define CNTRLREG_TSCSSENB BIT(0) >> @@ -127,6 +128,7 @@ >> >> /* Sequencer Status */ >> #define SEQ_STATUS BIT(5) >> +#define CHARGE_STEP 0x11 >> >> #define ADC_CLK 3000000 >> #define TOTAL_STEPS 16 > > The header changes should be split between the two Input and MFD > patches. > -- To unsubscribe from this list: send the line "unsubscribe linux-input" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
