From b10848e6f9fa7638fc0713695a12c0735ffb52b7 Mon Sep 17 00:00:00 2001 From: Vignesh R Date: Wed, 7 Jan 2015 11:19:36 +0530 Subject: mfd: ti_am335x_tscadc: Remove unwanted reg_se_cache save 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. Also, when ADC wakes up Sequencer should not be busy executing any of the config steps except for the charge step. Previously charge step was 1 ADC clock cycle and hence it was ignored. TSC steps are always disabled at the end of each conversion cycle, hence there is no need to explicitly disable TSC steps by writing 0 to REG_SE. Signed-off-by: Vignesh R Signed-off-by: Lee Jones --- drivers/mfd/ti_am335x_tscadc.c | 13 +++++-------- 1 file changed, 5 insertions(+), 8 deletions(-) (limited to 'drivers/mfd') diff --git a/drivers/mfd/ti_am335x_tscadc.c b/drivers/mfd/ti_am335x_tscadc.c index 467c80e1c4ae..e4e4b22eebc9 100644 --- a/drivers/mfd/ti_am335x_tscadc.c +++ b/drivers/mfd/ti_am335x_tscadc.c @@ -68,12 +68,6 @@ static void am335x_tscadc_need_adc(struct ti_tscadc_dev *tsadc) DEFINE_WAIT(wait); u32 reg; - /* - * disable TSC steps so it does not run while the ADC is using it. If - * write 0 while it is running (it just started or was already running) - * then it completes all steps that were enabled and stops then. - */ - tscadc_writel(tsadc, REG_SE, 0); reg = tscadc_readl(tsadc, REG_ADCFSM); if (reg & SEQ_STATUS) { tsadc->adc_waiting = true; @@ -86,8 +80,12 @@ 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) && !(reg & CHARGE_STEP)); tsadc->adc_waiting = false; } tsadc->adc_in_use = true; @@ -96,7 +94,6 @@ 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); -- cgit v1.2.1