diff options
author | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2024-09-09 08:36:23 +0200 |
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committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2024-09-09 08:36:23 +0200 |
commit | 895b4fae931a256f6c7c6c68f77a8e337980b5a1 (patch) | |
tree | 4e01d0293b8caee875fb7938d26ba9e0a572b314 /drivers/iio/adc/ad7606_par.c | |
parent | 72486eb13b254d0bee637a947f9ec46d01c37f04 (diff) | |
parent | da3ea35007d0af457a0afc87e84fddaebc4e0b63 (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.c | 48 |
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; } |