| Message ID | 20220609083213.1795019-8-claudiu.beznea@microchip.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | iio: adc: at91-sama5d2_adc: add support for temperature sensor | expand |
On Thu, 9 Jun 2022 11:32:04 +0300 Claudiu Beznea <claudiu.beznea@microchip.com> wrote: > Simplify a bit the code in at91_adc_read_info_raw() by reducing the > number of lines of code. > > Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com> I'm not convinced this is worth while, but there are some lesser steps visible in this patch that probably are. Given your earlier reorg to move at01_adc_adjust_val_osr() under the locks, you can now move the locks to the caller, thus not needing to handle them separately in all the exit paths. > --- > drivers/iio/adc/at91-sama5d2_adc.c | 35 +++++++++--------------------- > 1 file changed, 10 insertions(+), 25 deletions(-) > > diff --git a/drivers/iio/adc/at91-sama5d2_adc.c b/drivers/iio/adc/at91-sama5d2_adc.c > index b52f1020feaf..fbb98e216e70 100644 > --- a/drivers/iio/adc/at91-sama5d2_adc.c > +++ b/drivers/iio/adc/at91-sama5d2_adc.c > @@ -1576,6 +1576,7 @@ static int at91_adc_read_info_raw(struct iio_dev *indio_dev, > struct iio_chan_spec const *chan, int *val) > { > struct at91_adc_state *st = iio_priv(indio_dev); > + int (*fn)(struct at91_adc_state *, int, u16 *) = NULL; > u16 tmp_val; > int ret; > > @@ -1583,29 +1584,18 @@ static int at91_adc_read_info_raw(struct iio_dev *indio_dev, > * Keep in mind that we cannot use software trigger or touchscreen > * if external trigger is enabled > */ > - if (chan->type == IIO_POSITIONRELATIVE) { > - ret = iio_device_claim_direct_mode(indio_dev); > - if (ret) > - return ret; You can drop this out of the if statements as it happens in all paths. Or even better, move it to the caller.. > - mutex_lock(&st->lock); > - > - ret = at91_adc_read_position(st, chan->channel, > - &tmp_val); huh? ret not checked? > - *val = tmp_val; > - ret = at91_adc_adjust_val_osr(st, val); Sure this is duplicated, but meh it's only a few lines. > - mutex_unlock(&st->lock); > - iio_device_release_direct_mode(indio_dev); this early release (compared to the long path) is the only bit really gets duplicated in all paths.. > + if (chan->type == IIO_POSITIONRELATIVE) > + fn = at91_adc_read_position; > + if (chan->type == IIO_PRESSURE) > + fn = at91_adc_read_pressure; > > + ret = iio_device_claim_direct_mode(indio_dev); > + if (ret) > return ret; > - } > - if (chan->type == IIO_PRESSURE) { this should always have been an else if () as the chan->type couldn't be both. > - ret = iio_device_claim_direct_mode(indio_dev); > - if (ret) > - return ret; > - mutex_lock(&st->lock); hence this lot can be shared with the above. > + mutex_lock(&st->lock); > > - ret = at91_adc_read_pressure(st, chan->channel, > - &tmp_val); > + if (fn) { > + ret = fn(st, chan->channel, &tmp_val); > *val = tmp_val; > ret = at91_adc_adjust_val_osr(st, val); > mutex_unlock(&st->lock); > @@ -1616,11 +1606,6 @@ static int at91_adc_read_info_raw(struct iio_dev *indio_dev, > > /* in this case we have a voltage channel */ > > - ret = iio_device_claim_direct_mode(indio_dev); > - if (ret) > - return ret; > - mutex_lock(&st->lock); > - > st->chan = chan; > > at91_adc_cor(st, chan);
On 11.06.2022 20:54, Jonathan Cameron wrote: > EXTERNAL EMAIL: Do not click links or open attachments unless you know the content is safe > > On Thu, 9 Jun 2022 11:32:04 +0300 > Claudiu Beznea <claudiu.beznea@microchip.com> wrote: > >> Simplify a bit the code in at91_adc_read_info_raw() by reducing the >> number of lines of code. >> >> Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com> > > I'm not convinced this is worth while, but there are some lesser > steps visible in this patch that probably are. > > Given your earlier reorg to move at01_adc_adjust_val_osr() under the locks, > you can now move the locks to the caller, thus not needing to handle them > separately in all the exit paths. OK, I'll give it a try. With this, would you prefer to still keep this patch? > >> --- >> drivers/iio/adc/at91-sama5d2_adc.c | 35 +++++++++--------------------- >> 1 file changed, 10 insertions(+), 25 deletions(-) >> >> diff --git a/drivers/iio/adc/at91-sama5d2_adc.c b/drivers/iio/adc/at91-sama5d2_adc.c >> index b52f1020feaf..fbb98e216e70 100644 >> --- a/drivers/iio/adc/at91-sama5d2_adc.c >> +++ b/drivers/iio/adc/at91-sama5d2_adc.c >> @@ -1576,6 +1576,7 @@ static int at91_adc_read_info_raw(struct iio_dev *indio_dev, >> struct iio_chan_spec const *chan, int *val) >> { >> struct at91_adc_state *st = iio_priv(indio_dev); >> + int (*fn)(struct at91_adc_state *, int, u16 *) = NULL; >> u16 tmp_val; >> int ret; >> >> @@ -1583,29 +1584,18 @@ static int at91_adc_read_info_raw(struct iio_dev *indio_dev, >> * Keep in mind that we cannot use software trigger or touchscreen >> * if external trigger is enabled >> */ >> - if (chan->type == IIO_POSITIONRELATIVE) { >> - ret = iio_device_claim_direct_mode(indio_dev); >> - if (ret) >> - return ret; > > You can drop this out of the if statements as it happens in all paths. > Or even better, move it to the caller.. > >> - mutex_lock(&st->lock); >> - >> - ret = at91_adc_read_position(st, chan->channel, >> - &tmp_val); > > huh? ret not checked? Yep, this should have been missed... > >> - *val = tmp_val; >> - ret = at91_adc_adjust_val_osr(st, val); > Sure this is duplicated, but meh it's only a few lines. > > >> - mutex_unlock(&st->lock); >> - iio_device_release_direct_mode(indio_dev); > > this early release (compared to the long path) is the only bit really > gets duplicated in all paths.. > >> + if (chan->type == IIO_POSITIONRELATIVE) >> + fn = at91_adc_read_position; >> + if (chan->type == IIO_PRESSURE) >> + fn = at91_adc_read_pressure; >> >> + ret = iio_device_claim_direct_mode(indio_dev); >> + if (ret) >> return ret; >> - } >> - if (chan->type == IIO_PRESSURE) { > this should always have been an else if () as the chan->type couldn't be both. > >> - ret = iio_device_claim_direct_mode(indio_dev); >> - if (ret) >> - return ret; >> - mutex_lock(&st->lock); > hence this lot can be shared with the above. To be sure of what I've understood correctly: in the end you prefer to have a patch with the point you suggested rather then the initial patch? Thank you, Claudiu Beznea > >> + mutex_lock(&st->lock); >> >> - ret = at91_adc_read_pressure(st, chan->channel, >> - &tmp_val); >> + if (fn) { >> + ret = fn(st, chan->channel, &tmp_val); >> *val = tmp_val; >> ret = at91_adc_adjust_val_osr(st, val); >> mutex_unlock(&st->lock); >> @@ -1616,11 +1606,6 @@ static int at91_adc_read_info_raw(struct iio_dev *indio_dev, >> >> /* in this case we have a voltage channel */ >> >> - ret = iio_device_claim_direct_mode(indio_dev); >> - if (ret) >> - return ret; >> - mutex_lock(&st->lock); >> - >> st->chan = chan; >> >> at91_adc_cor(st, chan); >
On Tue, 14 Jun 2022 08:49:03 +0000 <Claudiu.Beznea@microchip.com> wrote: > On 11.06.2022 20:54, Jonathan Cameron wrote: > > EXTERNAL EMAIL: Do not click links or open attachments unless you know the content is safe > > > > On Thu, 9 Jun 2022 11:32:04 +0300 > > Claudiu Beznea <claudiu.beznea@microchip.com> wrote: > > > >> Simplify a bit the code in at91_adc_read_info_raw() by reducing the > >> number of lines of code. > >> > >> Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com> > > > > I'm not convinced this is worth while, but there are some lesser > > steps visible in this patch that probably are. > > > > Given your earlier reorg to move at01_adc_adjust_val_osr() under the locks, > > you can now move the locks to the caller, thus not needing to handle them > > separately in all the exit paths. > > OK, I'll give it a try. With this, would you prefer to still keep this patch? > No. I don't think it will bring enough benefit for the loss of readability. Having moved the locking, there will only be a few repeated lines. Jonathan
diff --git a/drivers/iio/adc/at91-sama5d2_adc.c b/drivers/iio/adc/at91-sama5d2_adc.c index b52f1020feaf..fbb98e216e70 100644 --- a/drivers/iio/adc/at91-sama5d2_adc.c +++ b/drivers/iio/adc/at91-sama5d2_adc.c @@ -1576,6 +1576,7 @@ static int at91_adc_read_info_raw(struct iio_dev *indio_dev, struct iio_chan_spec const *chan, int *val) { struct at91_adc_state *st = iio_priv(indio_dev); + int (*fn)(struct at91_adc_state *, int, u16 *) = NULL; u16 tmp_val; int ret; @@ -1583,29 +1584,18 @@ static int at91_adc_read_info_raw(struct iio_dev *indio_dev, * Keep in mind that we cannot use software trigger or touchscreen * if external trigger is enabled */ - if (chan->type == IIO_POSITIONRELATIVE) { - ret = iio_device_claim_direct_mode(indio_dev); - if (ret) - return ret; - mutex_lock(&st->lock); - - ret = at91_adc_read_position(st, chan->channel, - &tmp_val); - *val = tmp_val; - ret = at91_adc_adjust_val_osr(st, val); - mutex_unlock(&st->lock); - iio_device_release_direct_mode(indio_dev); + if (chan->type == IIO_POSITIONRELATIVE) + fn = at91_adc_read_position; + if (chan->type == IIO_PRESSURE) + fn = at91_adc_read_pressure; + ret = iio_device_claim_direct_mode(indio_dev); + if (ret) return ret; - } - if (chan->type == IIO_PRESSURE) { - ret = iio_device_claim_direct_mode(indio_dev); - if (ret) - return ret; - mutex_lock(&st->lock); + mutex_lock(&st->lock); - ret = at91_adc_read_pressure(st, chan->channel, - &tmp_val); + if (fn) { + ret = fn(st, chan->channel, &tmp_val); *val = tmp_val; ret = at91_adc_adjust_val_osr(st, val); mutex_unlock(&st->lock); @@ -1616,11 +1606,6 @@ static int at91_adc_read_info_raw(struct iio_dev *indio_dev, /* in this case we have a voltage channel */ - ret = iio_device_claim_direct_mode(indio_dev); - if (ret) - return ret; - mutex_lock(&st->lock); - st->chan = chan; at91_adc_cor(st, chan);
Simplify a bit the code in at91_adc_read_info_raw() by reducing the number of lines of code. Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com> --- drivers/iio/adc/at91-sama5d2_adc.c | 35 +++++++++--------------------- 1 file changed, 10 insertions(+), 25 deletions(-)