RE: [PATCH v3 3/6] mfd: ti_am335x_tscadc: Remove unwanted reg_se_cache save
From: "R, Vignesh" <vigneshr@ti.com>
Date: 2014-11-11 15:27:51
Also in:
linux-arm-kernel, linux-devicetree, linux-iio, linux-omap, lkml
On Tue, 11 Nov 2014, Vignesh R wrote:
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. Signed-off-by: Vignesh R <vigneshr@ti.com> ---
You need to provide a changelog here when submitting new versions. I have included changelog in the cover page. Will include them in individual patches next time.
quoted hunk ↗ jump to hunk
drivers/mfd/ti_am335x_tscadc.c | 7 +++++-- include/linux/mfd/ti_am335x_tscadc.h | 1 + 2 files changed, 6 insertions(+), 2 deletions(-)diff --git a/drivers/mfd/ti_am335x_tscadc.cb/drivers/mfd/ti_am335x_tscadc.c index d877e777cce6..110038859a8d 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) && !(reg & CHARGE_STEP)); tsadc->adc_waiting = false; } tsadc->adc_in_use = true;@@ -96,7 +100,6 @@ static void am335x_tscadc_need_adc(structti_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;
You didn't answer my question about this? I did reply to the question in the previous thread. Previously, TSC did not reliably re-enable its steps as the TSC irq handler received false pen up events. Hence, in order to use TSC after ADC operation, it was necessary to save and re-enable TSC steps (basically, to keep TSC steps enabled always). The change was more of a workaround to overcome limitation of TSC irq handler. With this series of patches, TSC irq handler is very reliable and the workaround is no longer required.
quoted hunk ↗ jump to hunk
am335x_tscadc_need_adc(tsadc); tscadc_writel(tsadc, REG_SE, val);diff --git a/include/linux/mfd/ti_am335x_tscadc.hb/include/linux/mfd/ti_am335x_tscadc.h index c99be5dc0f5c..fcce182e4a35 100644--- a/include/linux/mfd/ti_am335x_tscadc.h +++ b/include/linux/mfd/ti_am335x_tscadc.h@@ -128,6 +128,7 @@ /* Sequencer Status */ #define SEQ_STATUS BIT(5) +#define CHARGE_STEP 0x11 #define ADC_CLK 3000000 #define TOTAL_STEPS 16
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