diff options
| author | Ian Abbott <abbotti@mev.co.uk> | 2019-03-19 16:54:43 +0000 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2019-03-20 08:25:17 +0100 |
| commit | 018768ccc7dc582519b84df593dd8ff1fbd02b55 (patch) | |
| tree | bcf454a586acb640859c96e4565e3bcf749f572c /drivers/staging/comedi | |
| parent | 776d25ff5b494be280caba9d297477270462e580 (diff) | |
staging: comedi: ni_mio_common: use insn->n in ni_eeprom_insn_read()
The `insn_read` handler for the EEPROM subdevice on E-series boards
(`ni_eeprom_insn_read()`) currently ignores `insn->n` (the number of
samples to read) and assumes a single sample is to be read into
`data[0]`. Fortunately, the Comedi core ensures that `data[]` has a
length of at least 16 so there is no problem with array bounds.
The usual Comedi convention for `insn_read` handlers is to read the same
channel `insn->n` times into successive elements of `data[]` so let's do
that. (Each channel number corresponds to a single EEPROM address.)
Since we do not expect the EEPROM data at a particular address to change
between readings, let's just read it once and copy the value `insn->n`
times.
Also, follow the usual Comedi convention and return `insn->n` from the
handler to indicate success (although any non-negative value will do).
Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/staging/comedi')
| -rw-r--r-- | drivers/staging/comedi/drivers/ni_mio_common.c | 10 |
1 files changed, 8 insertions, 2 deletions
diff --git a/drivers/staging/comedi/drivers/ni_mio_common.c b/drivers/staging/comedi/drivers/ni_mio_common.c index e008095436d7..5b397ad2a604 100644 --- a/drivers/staging/comedi/drivers/ni_mio_common.c +++ b/drivers/staging/comedi/drivers/ni_mio_common.c @@ -4507,9 +4507,15 @@ static int ni_eeprom_insn_read(struct comedi_device *dev, struct comedi_insn *insn, unsigned int *data) { - data[0] = ni_read_eeprom(dev, CR_CHAN(insn->chanspec)); + unsigned int val; + unsigned int i; - return 1; + if (insn->n) { + val = ni_read_eeprom(dev, CR_CHAN(insn->chanspec)); + for (i = 0; i < insn->n; i++) + data[i] = val; + } + return insn->n; } static int ni_m_series_eeprom_insn_read(struct comedi_device *dev, |