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authorLinus Torvalds <torvalds@linux-foundation.org>2013-08-10 09:00:51 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2013-08-10 09:00:51 -0700
commit8ae3f1d09566038606a18576604ecc957a935c48 (patch)
tree428a087efd8596ec38c2cf9af557eac97d887353
parente6e8ac441cd2c1fed16f1864b170d9d471aeb7fe (diff)
parentcefe8a32f2a5887246ed250115e34bee6ecc8d61 (diff)
Merge tag 'staging-3.11-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging
Pull staging driver fixes from Greg KH: "Here are 3 small fixes for staging/IIO drivers for 3.11-rc5. Nothing huge, two IIO driver fixes, and a zcache fix. All of these have been in linux-next for a while" * tag 'staging-3.11-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging: staging: zcache: fix "zcache=" kernel parameter iio: ti_am335x_adc: Fix wrong samples received on 1st read iio:trigger: Fix use_count race condition
-rw-r--r--drivers/iio/adc/ti_am335x_adc.c30
-rw-r--r--drivers/iio/industrialio-trigger.c34
-rw-r--r--drivers/staging/zcache/zcache-main.c6
-rw-r--r--include/linux/iio/trigger.h3
-rw-r--r--include/linux/mfd/ti_am335x_tscadc.h16
5 files changed, 66 insertions, 23 deletions
diff --git a/drivers/iio/adc/ti_am335x_adc.c b/drivers/iio/adc/ti_am335x_adc.c
index 0ad208a69c2..3ceac3e91dd 100644
--- a/drivers/iio/adc/ti_am335x_adc.c
+++ b/drivers/iio/adc/ti_am335x_adc.c
@@ -60,7 +60,6 @@ static void tiadc_step_config(struct tiadc_device *adc_dev)
{
unsigned int stepconfig;
int i, steps;
- u32 step_en;
/*
* There are 16 configurable steps and 8 analog input
@@ -86,8 +85,7 @@ static void tiadc_step_config(struct tiadc_device *adc_dev)
adc_dev->channel_step[i] = steps;
steps++;
}
- step_en = get_adc_step_mask(adc_dev);
- am335x_tsc_se_set(adc_dev->mfd_tscadc, step_en);
+
}
static const char * const chan_name_ain[] = {
@@ -142,10 +140,22 @@ static int tiadc_read_raw(struct iio_dev *indio_dev,
int *val, int *val2, long mask)
{
struct tiadc_device *adc_dev = iio_priv(indio_dev);
- int i;
- unsigned int fifo1count, read;
+ int i, map_val;
+ unsigned int fifo1count, read, stepid;
u32 step = UINT_MAX;
bool found = false;
+ u32 step_en;
+ unsigned long timeout = jiffies + usecs_to_jiffies
+ (IDLE_TIMEOUT * adc_dev->channels);
+ step_en = get_adc_step_mask(adc_dev);
+ am335x_tsc_se_set(adc_dev->mfd_tscadc, step_en);
+
+ /* Wait for ADC sequencer to complete sampling */
+ while (tiadc_readl(adc_dev, REG_ADCFSM) & SEQ_STATUS) {
+ if (time_after(jiffies, timeout))
+ return -EAGAIN;
+ }
+ map_val = chan->channel + TOTAL_CHANNELS;
/*
* When the sub-system is first enabled,
@@ -170,12 +180,16 @@ static int tiadc_read_raw(struct iio_dev *indio_dev,
fifo1count = tiadc_readl(adc_dev, REG_FIFO1CNT);
for (i = 0; i < fifo1count; i++) {
read = tiadc_readl(adc_dev, REG_FIFO1);
- if (read >> 16 == step) {
- *val = read & 0xfff;
+ stepid = read & FIFOREAD_CHNLID_MASK;
+ stepid = stepid >> 0x10;
+
+ if (stepid == map_val) {
+ read = read & FIFOREAD_DATA_MASK;
found = true;
+ *val = read;
}
}
- am335x_tsc_se_update(adc_dev->mfd_tscadc);
+
if (found == false)
return -EBUSY;
return IIO_VAL_INT;
diff --git a/drivers/iio/industrialio-trigger.c b/drivers/iio/industrialio-trigger.c
index ea8a4146620..0dd9bb87313 100644
--- a/drivers/iio/industrialio-trigger.c
+++ b/drivers/iio/industrialio-trigger.c
@@ -127,12 +127,17 @@ static struct iio_trigger *iio_trigger_find_by_name(const char *name,
void iio_trigger_poll(struct iio_trigger *trig, s64 time)
{
int i;
- if (!trig->use_count)
- for (i = 0; i < CONFIG_IIO_CONSUMERS_PER_TRIGGER; i++)
- if (trig->subirqs[i].enabled) {
- trig->use_count++;
+
+ if (!atomic_read(&trig->use_count)) {
+ atomic_set(&trig->use_count, CONFIG_IIO_CONSUMERS_PER_TRIGGER);
+
+ for (i = 0; i < CONFIG_IIO_CONSUMERS_PER_TRIGGER; i++) {
+ if (trig->subirqs[i].enabled)
generic_handle_irq(trig->subirq_base + i);
- }
+ else
+ iio_trigger_notify_done(trig);
+ }
+ }
}
EXPORT_SYMBOL(iio_trigger_poll);
@@ -146,19 +151,24 @@ EXPORT_SYMBOL(iio_trigger_generic_data_rdy_poll);
void iio_trigger_poll_chained(struct iio_trigger *trig, s64 time)
{
int i;
- if (!trig->use_count)
- for (i = 0; i < CONFIG_IIO_CONSUMERS_PER_TRIGGER; i++)
- if (trig->subirqs[i].enabled) {
- trig->use_count++;
+
+ if (!atomic_read(&trig->use_count)) {
+ atomic_set(&trig->use_count, CONFIG_IIO_CONSUMERS_PER_TRIGGER);
+
+ for (i = 0; i < CONFIG_IIO_CONSUMERS_PER_TRIGGER; i++) {
+ if (trig->subirqs[i].enabled)
handle_nested_irq(trig->subirq_base + i);
- }
+ else
+ iio_trigger_notify_done(trig);
+ }
+ }
}
EXPORT_SYMBOL(iio_trigger_poll_chained);
void iio_trigger_notify_done(struct iio_trigger *trig)
{
- trig->use_count--;
- if (trig->use_count == 0 && trig->ops && trig->ops->try_reenable)
+ if (atomic_dec_and_test(&trig->use_count) && trig->ops &&
+ trig->ops->try_reenable)
if (trig->ops->try_reenable(trig))
/* Missed an interrupt so launch new poll now */
iio_trigger_poll(trig, 0);
diff --git a/drivers/staging/zcache/zcache-main.c b/drivers/staging/zcache/zcache-main.c
index dcceed29d31..81972fa47be 100644
--- a/drivers/staging/zcache/zcache-main.c
+++ b/drivers/staging/zcache/zcache-main.c
@@ -1811,10 +1811,12 @@ static int zcache_comp_init(void)
#else
if (*zcache_comp_name != '\0') {
ret = crypto_has_comp(zcache_comp_name, 0, 0);
- if (!ret)
+ if (!ret) {
pr_info("zcache: %s not supported\n",
zcache_comp_name);
- goto out;
+ ret = 1;
+ goto out;
+ }
}
if (!ret)
strcpy(zcache_comp_name, "lzo");
diff --git a/include/linux/iio/trigger.h b/include/linux/iio/trigger.h
index 3869c525b05..369cf2cd514 100644
--- a/include/linux/iio/trigger.h
+++ b/include/linux/iio/trigger.h
@@ -8,6 +8,7 @@
*/
#include <linux/irq.h>
#include <linux/module.h>
+#include <linux/atomic.h>
#ifndef _IIO_TRIGGER_H_
#define _IIO_TRIGGER_H_
@@ -61,7 +62,7 @@ struct iio_trigger {
struct list_head list;
struct list_head alloc_list;
- int use_count;
+ atomic_t use_count;
struct irq_chip subirq_chip;
int subirq_base;
diff --git a/include/linux/mfd/ti_am335x_tscadc.h b/include/linux/mfd/ti_am335x_tscadc.h
index 8d73fe29796..db1791bb997 100644
--- a/include/linux/mfd/ti_am335x_tscadc.h
+++ b/include/linux/mfd/ti_am335x_tscadc.h
@@ -113,11 +113,27 @@
#define CNTRLREG_8WIRE CNTRLREG_AFE_CTRL(3)
#define CNTRLREG_TSCENB BIT(7)
+/* FIFO READ Register */
+#define FIFOREAD_DATA_MASK (0xfff << 0)
+#define FIFOREAD_CHNLID_MASK (0xf << 16)
+
+/* Sequencer Status */
+#define SEQ_STATUS BIT(5)
+
#define ADC_CLK 3000000
#define MAX_CLK_DIV 7
#define TOTAL_STEPS 16
#define TOTAL_CHANNELS 8
+/*
+* ADC runs at 3MHz, and it takes
+* 15 cycles to latch one data output.
+* Hence the idle time for ADC to
+* process one sample data would be
+* around 5 micro seconds.
+*/
+#define IDLE_TIMEOUT 5 /* microsec */
+
#define TSCADC_CELLS 2
struct ti_tscadc_dev {