2020-04-23 19:35:17

by Oscar Carter

Subject: [PATCH v2] staging: vt6656: Add formula to the vnt_rf_addpower function

Use a formula to calculate the return value of the vnt_rf_addpower
function instead of the "if" statement with literal values for every
case.

Signed-off-by: Oscar Carter <[email protected]>
---
Changelog v1 -> v2
- Change the type of "base" variable from s32 to int as Dan Carpenter
suggested.
- Remove the "--" postoperator and replace with (base - 1) as Dan
Carpenter suggested. Also, as this expression has a minus before the
parenthesis, remove it an apply the minus operator changing the sign of
"base" and literal "1".

drivers/staging/vt6656/rf.c | 20 +++-----------------
1 file changed, 3 insertions(+), 17 deletions(-)

diff --git a/drivers/staging/vt6656/rf.c b/drivers/staging/vt6656/rf.c
index 06fa8867cfa3..612fd4a59f8a 100644
--- a/drivers/staging/vt6656/rf.c
+++ b/drivers/staging/vt6656/rf.c
@@ -538,28 +538,14 @@ int vnt_rf_write_embedded(struct vnt_private *priv, u32 data)

static u8 vnt_rf_addpower(struct vnt_private *priv)
{
+ int base;
s32 rssi = -priv->current_rssi;

if (!rssi)
return 7;

- if (priv->rf_type == RF_VT3226D0) {
- if (rssi < -70)
- return 9;
- else if (rssi < -65)
- return 7;
- else if (rssi < -60)
- return 5;
- } else {
- if (rssi < -80)
- return 9;
- else if (rssi < -75)
- return 7;
- else if (rssi < -70)
- return 5;
- }
-
- return 0;
+ base = (priv->rf_type == RF_VT3226D0) ? -60 : -70;
+ return (rssi < base) ? ((rssi - base + 1) / -5) * 2 + 5 : 0;
}

/* Set Tx power by power level and rate */
--
2.20.1

2020-04-25 10:59:31

by Greg Kroah-Hartman

Subject: Re: [PATCH v2] staging: vt6656: Add formula to the vnt_rf_addpower function

On Thu, Apr 23, 2020 at 07:05:57PM +0200, Oscar Carter wrote:
> Use a formula to calculate the return value of the vnt_rf_addpower
> function instead of the "if" statement with literal values for every
> case.
>
> Signed-off-by: Oscar Carter <[email protected]>
> ---
> Changelog v1 -> v2
> - Change the type of "base" variable from s32 to int as Dan Carpenter
> suggested.
> - Remove the "--" postoperator and replace with (base - 1) as Dan
> Carpenter suggested. Also, as this expression has a minus before the
> parenthesis, remove it an apply the minus operator changing the sign of
> "base" and literal "1".
>
> drivers/staging/vt6656/rf.c | 20 +++-----------------
> 1 file changed, 3 insertions(+), 17 deletions(-)
>
> diff --git a/drivers/staging/vt6656/rf.c b/drivers/staging/vt6656/rf.c
> index 06fa8867cfa3..612fd4a59f8a 100644
> --- a/drivers/staging/vt6656/rf.c
> +++ b/drivers/staging/vt6656/rf.c
> @@ -538,28 +538,14 @@ int vnt_rf_write_embedded(struct vnt_private *priv, u32 data)
>
> static u8 vnt_rf_addpower(struct vnt_private *priv)
> {
> + int base;
> s32 rssi = -priv->current_rssi;
>
> if (!rssi)
> return 7;
>
> - if (priv->rf_type == RF_VT3226D0) {
> - if (rssi < -70)
> - return 9;
> - else if (rssi < -65)
> - return 7;
> - else if (rssi < -60)
> - return 5;
> - } else {
> - if (rssi < -80)
> - return 9;
> - else if (rssi < -75)
> - return 7;
> - else if (rssi < -70)
> - return 5;
> - }
> -
> - return 0;
> + base = (priv->rf_type == RF_VT3226D0) ? -60 : -70;
> + return (rssi < base) ? ((rssi - base + 1) / -5) * 2 + 5 : 0;

I _hate_ ? : functions, just spell this out please as a real if()
statement.

thanks,

greg k-h

2020-04-25 14:08:31

by Oscar Carter

Subject: Re: [PATCH v2] staging: vt6656: Add formula to the vnt_rf_addpower function

On Sat, Apr 25, 2020 at 12:57:14PM +0200, Greg Kroah-Hartman wrote:
> On Thu, Apr 23, 2020 at 07:05:57PM +0200, Oscar Carter wrote:
> > Use a formula to calculate the return value of the vnt_rf_addpower
> > function instead of the "if" statement with literal values for every
> > case.
> >
> > Signed-off-by: Oscar Carter <[email protected]>
> > ---
> > Changelog v1 -> v2
> > - Change the type of "base" variable from s32 to int as Dan Carpenter
> > suggested.
> > - Remove the "--" postoperator and replace with (base - 1) as Dan
> > Carpenter suggested. Also, as this expression has a minus before the
> > parenthesis, remove it an apply the minus operator changing the sign of
> > "base" and literal "1".
> >
> > drivers/staging/vt6656/rf.c | 20 +++-----------------
> > 1 file changed, 3 insertions(+), 17 deletions(-)
> >
> > diff --git a/drivers/staging/vt6656/rf.c b/drivers/staging/vt6656/rf.c
> > index 06fa8867cfa3..612fd4a59f8a 100644
> > --- a/drivers/staging/vt6656/rf.c
> > +++ b/drivers/staging/vt6656/rf.c
> > @@ -538,28 +538,14 @@ int vnt_rf_write_embedded(struct vnt_private *priv, u32 data)
> >
> > static u8 vnt_rf_addpower(struct vnt_private *priv)
> > {
> > + int base;
> > s32 rssi = -priv->current_rssi;
> >
> > if (!rssi)
> > return 7;
> >
> > - if (priv->rf_type == RF_VT3226D0) {
> > - if (rssi < -70)
> > - return 9;
> > - else if (rssi < -65)
> > - return 7;
> > - else if (rssi < -60)
> > - return 5;
> > - } else {
> > - if (rssi < -80)
> > - return 9;
> > - else if (rssi < -75)
> > - return 7;
> > - else if (rssi < -70)
> > - return 5;
> > - }
> > -
> > - return 0;
> > + base = (priv->rf_type == RF_VT3226D0) ? -60 : -70;
> > + return (rssi < base) ? ((rssi - base + 1) / -5) * 2 + 5 : 0;
>
> I _hate_ ? : functions, just spell this out please as a real if()
> statement.
>
Ok, I will do the modification and I will resend a new version patch.

> thanks,
>
> greg k-h

thanks,

oscar carter