[3.16.y-ckt stable] Patch "mfd: ti_am335x_tscadc: Fix TSC operation after ADC continouous mode" has been added to staging queue

[Luis Henriques]

This is a note to let you know that I have just added a patch titled

    mfd: ti_am335x_tscadc: Fix TSC operation after ADC continouous mode

to the linux-3.16.y-queue branch of the 3.16.y-ckt extended stable tree 
which can be found at:

 http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.16.y-queue

This patch is scheduled to be released in version 3.16.7-ckt2.

If you, or anyone else, feels it should not be added to this tree, please 
reply to this email.

For more information about the 3.16.y-ckt tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Luis

------

>From b3ed743dbc43604d312237f161bdecff13a87ef3 Mon Sep 17 00:00:00 2001
From: Vignesh R <vigneshr at ti.com>
Date: Mon, 1 Sep 2014 12:01:06 +0530
Subject: mfd: ti_am335x_tscadc: Fix TSC operation after ADC continouous mode

commit 6ac734d2242949f41eb1346ca0fd4ed010c937aa upstream.

After enabling and disabling ADC continuous mode via sysfs, ts_print_raw
fails to return any data. This is because when ADC is configured for
continuous mode, it disables touch screen steps.These steps are not
re-enabled when ADC continuous mode is disabled. Therefore existing values
of REG_SE needs to be cached before enabling continuous mode and
disabling touch screen steps and enabling ADC steps. The cached value
are to be restored to REG_SE once ADC is disabled.

Fixes: 7ca6740cd1cd ("mfd: input: iio: ti_amm335x: Rework TSC/ADC synchronization")

Signed-off-by: Vignesh R <vigneshr at ti.com>
Signed-off-by: Lee Jones <lee.jones at linaro.org>
Signed-off-by: Luis Henriques <luis.henriques at canonical.com>
---
 drivers/mfd/ti_am335x_tscadc.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/mfd/ti_am335x_tscadc.c b/drivers/mfd/ti_am335x_tscadc.c
index dd4bf5816221..8b119ce20b93 100644
--- a/drivers/mfd/ti_am335x_tscadc.c
+++ b/drivers/mfd/ti_am335x_tscadc.c
@@ -53,7 +53,7 @@ void am335x_tsc_se_set_cache(struct ti_tscadc_dev *tsadc, u32 val)
 	unsigned long flags;

 	spin_lock_irqsave(&tsadc->reg_lock, flags);
-	tsadc->reg_se_cache = val;
+	tsadc->reg_se_cache |= val;
 	if (tsadc->adc_waiting)
 		wake_up(&tsadc->reg_se_wait);
 	else if (!tsadc->adc_in_use)
@@ -96,6 +96,7 @@ 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);
--
2.1.0