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authorGreg Kroah-Hartman <gregkh@linuxfoundation.org>2024-09-09 08:36:23 +0200
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2024-09-09 08:36:23 +0200
commit895b4fae931a256f6c7c6c68f77a8e337980b5a1 (patch)
tree4e01d0293b8caee875fb7938d26ba9e0a572b314 /drivers/iio/adc/ad7606_par.c
parent72486eb13b254d0bee637a947f9ec46d01c37f04 (diff)
parentda3ea35007d0af457a0afc87e84fddaebc4e0b63 (diff)
Merge 6.11-rc7 into char-misc-next
We need the char-misc fixes in here as well. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/iio/adc/ad7606_par.c')
-rw-r--r--drivers/iio/adc/ad7606_par.c48
1 files changed, 45 insertions, 3 deletions
diff --git a/drivers/iio/adc/ad7606_par.c b/drivers/iio/adc/ad7606_par.c
index b5975bbfcbe0..02d8c309304e 100644
--- a/drivers/iio/adc/ad7606_par.c
+++ b/drivers/iio/adc/ad7606_par.c
@@ -7,6 +7,7 @@
#include <linux/mod_devicetable.h>
#include <linux/module.h>
+#include <linux/gpio/consumer.h>
#include <linux/platform_device.h>
#include <linux/types.h>
#include <linux/err.h>
@@ -21,8 +22,29 @@ static int ad7606_par16_read_block(struct device *dev,
struct iio_dev *indio_dev = dev_get_drvdata(dev);
struct ad7606_state *st = iio_priv(indio_dev);
- insw((unsigned long)st->base_address, buf, count);
+ /*
+ * On the parallel interface, the frstdata signal is set to high while
+ * and after reading the sample of the first channel and low for all
+ * other channels. This can be used to check that the incoming data is
+ * correctly aligned. During normal operation the data should never
+ * become unaligned, but some glitch or electrostatic discharge might
+ * cause an extra read or clock cycle. Monitoring the frstdata signal
+ * allows to recover from such failure situations.
+ */
+ int num = count;
+ u16 *_buf = buf;
+
+ if (st->gpio_frstdata) {
+ insw((unsigned long)st->base_address, _buf, 1);
+ if (!gpiod_get_value(st->gpio_frstdata)) {
+ ad7606_reset(st);
+ return -EIO;
+ }
+ _buf++;
+ num--;
+ }
+ insw((unsigned long)st->base_address, _buf, num);
return 0;
}
@@ -35,8 +57,28 @@ static int ad7606_par8_read_block(struct device *dev,
{
struct iio_dev *indio_dev = dev_get_drvdata(dev);
struct ad7606_state *st = iio_priv(indio_dev);
-
- insb((unsigned long)st->base_address, buf, count * 2);
+ /*
+ * On the parallel interface, the frstdata signal is set to high while
+ * and after reading the sample of the first channel and low for all
+ * other channels. This can be used to check that the incoming data is
+ * correctly aligned. During normal operation the data should never
+ * become unaligned, but some glitch or electrostatic discharge might
+ * cause an extra read or clock cycle. Monitoring the frstdata signal
+ * allows to recover from such failure situations.
+ */
+ int num = count;
+ u16 *_buf = buf;
+
+ if (st->gpio_frstdata) {
+ insb((unsigned long)st->base_address, _buf, 2);
+ if (!gpiod_get_value(st->gpio_frstdata)) {
+ ad7606_reset(st);
+ return -EIO;
+ }
+ _buf++;
+ num--;
+ }
+ insb((unsigned long)st->base_address, _buf, num * 2);
return 0;
}