* [PATCH] net: can: cc770: Simplify parsing DT properties
@ 2024-08-28 13:19 Rob Herring (Arm)
2024-08-28 16:16 ` Simon Horman
0 siblings, 1 reply; 5+ messages in thread
From: Rob Herring (Arm) @ 2024-08-28 13:19 UTC (permalink / raw)
To: Marc Kleine-Budde, Vincent Mailhol, David S. Miller, Eric Dumazet,
Jakub Kicinski, Paolo Abeni
Cc: linux-can, netdev, linux-kernel
Use of the typed property accessors is preferred over of_get_property().
The existing code doesn't work on little endian systems either. Replace
the of_get_property() calls with of_property_read_bool() and
of_property_read_u32().
Signed-off-by: Rob Herring (Arm) <robh@kernel.org>
---
drivers/net/can/cc770/cc770_platform.c | 29 ++++++++------------------
1 file changed, 9 insertions(+), 20 deletions(-)
diff --git a/drivers/net/can/cc770/cc770_platform.c b/drivers/net/can/cc770/cc770_platform.c
index 13bcfba05f18..9993568154f8 100644
--- a/drivers/net/can/cc770/cc770_platform.c
+++ b/drivers/net/can/cc770/cc770_platform.c
@@ -71,16 +71,9 @@ static int cc770_get_of_node_data(struct platform_device *pdev,
struct cc770_priv *priv)
{
struct device_node *np = pdev->dev.of_node;
- const u32 *prop;
- int prop_size;
- u32 clkext;
-
- prop = of_get_property(np, "bosch,external-clock-frequency",
- &prop_size);
- if (prop && (prop_size == sizeof(u32)))
- clkext = *prop;
- else
- clkext = CC770_PLATFORM_CAN_CLOCK; /* default */
+ u32 clkext = CC770_PLATFORM_CAN_CLOCK, clkout = 0;
+
+ of_property_read_u32(np, "bosch,external-clock-frequency", &clkext);
priv->can.clock.freq = clkext;
/* The system clock may not exceed 10 MHz */
@@ -98,7 +91,7 @@ static int cc770_get_of_node_data(struct platform_device *pdev,
if (of_property_read_bool(np, "bosch,iso-low-speed-mux"))
priv->cpu_interface |= CPUIF_MUX;
- if (!of_get_property(np, "bosch,no-comperator-bypass", NULL))
+ if (!of_property_read_bool(np, "bosch,no-comperator-bypass"))
priv->bus_config |= BUSCFG_CBY;
if (of_property_read_bool(np, "bosch,disconnect-rx0-input"))
priv->bus_config |= BUSCFG_DR0;
@@ -109,20 +102,16 @@ static int cc770_get_of_node_data(struct platform_device *pdev,
if (of_property_read_bool(np, "bosch,polarity-dominant"))
priv->bus_config |= BUSCFG_POL;
- prop = of_get_property(np, "bosch,clock-out-frequency", &prop_size);
- if (prop && (prop_size == sizeof(u32)) && *prop > 0) {
- u32 cdv = clkext / *prop;
- int slew;
+ of_property_read_u32(np, "bosch,clock-out-frequency", &clkout);
+ if (clkout > 0) {
+ u32 cdv = clkext / clkout;
+ u32 slew;
if (cdv > 0 && cdv < 16) {
priv->cpu_interface |= CPUIF_CEN;
priv->clkout |= (cdv - 1) & CLKOUT_CD_MASK;
- prop = of_get_property(np, "bosch,slew-rate",
- &prop_size);
- if (prop && (prop_size == sizeof(u32))) {
- slew = *prop;
- } else {
+ if (of_property_read_u32(np, "bosch,slew-rate", &slew)) {
/* Determine default slew rate */
slew = (CLKOUT_SL_MASK >>
CLKOUT_SL_SHIFT) -
--
2.45.2
^ permalink raw reply related [flat|nested] 5+ messages in thread
* Re: [PATCH] net: can: cc770: Simplify parsing DT properties
2024-08-28 13:19 [PATCH] net: can: cc770: Simplify parsing DT properties Rob Herring (Arm)
@ 2024-08-28 16:16 ` Simon Horman
2024-08-29 19:35 ` Marc Kleine-Budde
0 siblings, 1 reply; 5+ messages in thread
From: Simon Horman @ 2024-08-28 16:16 UTC (permalink / raw)
To: Rob Herring (Arm)
Cc: Marc Kleine-Budde, Vincent Mailhol, David S. Miller, Eric Dumazet,
Jakub Kicinski, Paolo Abeni, linux-can, netdev, linux-kernel
On Wed, Aug 28, 2024 at 08:19:02AM -0500, Rob Herring (Arm) wrote:
> Use of the typed property accessors is preferred over of_get_property().
> The existing code doesn't work on little endian systems either. Replace
> the of_get_property() calls with of_property_read_bool() and
> of_property_read_u32().
>
> Signed-off-by: Rob Herring (Arm) <robh@kernel.org>
...
> diff --git a/drivers/net/can/cc770/cc770_platform.c b/drivers/net/can/cc770/cc770_platform.c
> index 13bcfba05f18..9993568154f8 100644
> --- a/drivers/net/can/cc770/cc770_platform.c
> +++ b/drivers/net/can/cc770/cc770_platform.c
> @@ -71,16 +71,9 @@ static int cc770_get_of_node_data(struct platform_device *pdev,
> struct cc770_priv *priv)
> {
> struct device_node *np = pdev->dev.of_node;
> - const u32 *prop;
> - int prop_size;
> - u32 clkext;
> -
> - prop = of_get_property(np, "bosch,external-clock-frequency",
> - &prop_size);
> - if (prop && (prop_size == sizeof(u32)))
> - clkext = *prop;
> - else
> - clkext = CC770_PLATFORM_CAN_CLOCK; /* default */
> + u32 clkext = CC770_PLATFORM_CAN_CLOCK, clkout = 0;
Marc,
Could you clarify if reverse xmas tree ordering - longest line to shortest
- of local variables is desired for can code? If so, I'm flagging that the
above now doesn't follow that scheme.
> +
> + of_property_read_u32(np, "bosch,external-clock-frequency", &clkext);
> priv->can.clock.freq = clkext;
>
> /* The system clock may not exceed 10 MHz */
...
> @@ -109,20 +102,16 @@ static int cc770_get_of_node_data(struct platform_device *pdev,
> if (of_property_read_bool(np, "bosch,polarity-dominant"))
> priv->bus_config |= BUSCFG_POL;
>
> - prop = of_get_property(np, "bosch,clock-out-frequency", &prop_size);
> - if (prop && (prop_size == sizeof(u32)) && *prop > 0) {
> - u32 cdv = clkext / *prop;
> - int slew;
> + of_property_read_u32(np, "bosch,clock-out-frequency", &clkout);
> + if (clkout > 0) {
> + u32 cdv = clkext / clkout;
> + u32 slew;
>
> if (cdv > 0 && cdv < 16) {
> priv->cpu_interface |= CPUIF_CEN;
> priv->clkout |= (cdv - 1) & CLKOUT_CD_MASK;
>
> - prop = of_get_property(np, "bosch,slew-rate",
> - &prop_size);
> - if (prop && (prop_size == sizeof(u32))) {
> - slew = *prop;
> - } else {
> + if (of_property_read_u32(np, "bosch,slew-rate", &slew)) {
> /* Determine default slew rate */
> slew = (CLKOUT_SL_MASK >>
> CLKOUT_SL_SHIFT) -
Rob,
The next few lines look like this:
((cdv * clkext - 1) / 8000000);
if (slew < 0)
slew = 0;
But slew is now unsigned, so this check will always be false.
Flagged by Smatch and Coccinelle.
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [PATCH] net: can: cc770: Simplify parsing DT properties
2024-08-28 16:16 ` Simon Horman
@ 2024-08-29 19:35 ` Marc Kleine-Budde
0 siblings, 0 replies; 5+ messages in thread
From: Marc Kleine-Budde @ 2024-08-29 19:35 UTC (permalink / raw)
To: Simon Horman
Cc: Rob Herring (Arm), Vincent Mailhol, David S. Miller, Eric Dumazet,
Jakub Kicinski, Paolo Abeni, linux-can, netdev, linux-kernel
[-- Attachment #1: Type: text/plain, Size: 3330 bytes --]
On 28.08.2024 17:16:24, Simon Horman wrote:
> On Wed, Aug 28, 2024 at 08:19:02AM -0500, Rob Herring (Arm) wrote:
> > Use of the typed property accessors is preferred over of_get_property().
> > The existing code doesn't work on little endian systems either. Replace
> > the of_get_property() calls with of_property_read_bool() and
> > of_property_read_u32().
> >
> > Signed-off-by: Rob Herring (Arm) <robh@kernel.org>
>
> ...
>
> > diff --git a/drivers/net/can/cc770/cc770_platform.c b/drivers/net/can/cc770/cc770_platform.c
> > index 13bcfba05f18..9993568154f8 100644
> > --- a/drivers/net/can/cc770/cc770_platform.c
> > +++ b/drivers/net/can/cc770/cc770_platform.c
> > @@ -71,16 +71,9 @@ static int cc770_get_of_node_data(struct platform_device *pdev,
> > struct cc770_priv *priv)
> > {
> > struct device_node *np = pdev->dev.of_node;
> > - const u32 *prop;
> > - int prop_size;
> > - u32 clkext;
> > -
> > - prop = of_get_property(np, "bosch,external-clock-frequency",
> > - &prop_size);
> > - if (prop && (prop_size == sizeof(u32)))
> > - clkext = *prop;
> > - else
> > - clkext = CC770_PLATFORM_CAN_CLOCK; /* default */
> > + u32 clkext = CC770_PLATFORM_CAN_CLOCK, clkout = 0;
>
> Marc,
>
> Could you clarify if reverse xmas tree ordering - longest line to shortest
> - of local variables is desired for can code? If so, I'm flagging that the
> above now doesn't follow that scheme.
If you touch the code, and noting speaks against it, please make it
reverse xmas.
>
> > +
> > + of_property_read_u32(np, "bosch,external-clock-frequency", &clkext);
> > priv->can.clock.freq = clkext;
> >
> > /* The system clock may not exceed 10 MHz */
>
> ...
>
> > @@ -109,20 +102,16 @@ static int cc770_get_of_node_data(struct platform_device *pdev,
> > if (of_property_read_bool(np, "bosch,polarity-dominant"))
> > priv->bus_config |= BUSCFG_POL;
> >
> > - prop = of_get_property(np, "bosch,clock-out-frequency", &prop_size);
> > - if (prop && (prop_size == sizeof(u32)) && *prop > 0) {
> > - u32 cdv = clkext / *prop;
> > - int slew;
> > + of_property_read_u32(np, "bosch,clock-out-frequency", &clkout);
> > + if (clkout > 0) {
> > + u32 cdv = clkext / clkout;
> > + u32 slew;
> >
> > if (cdv > 0 && cdv < 16) {
> > priv->cpu_interface |= CPUIF_CEN;
> > priv->clkout |= (cdv - 1) & CLKOUT_CD_MASK;
> >
> > - prop = of_get_property(np, "bosch,slew-rate",
> > - &prop_size);
> > - if (prop && (prop_size == sizeof(u32))) {
> > - slew = *prop;
> > - } else {
> > + if (of_property_read_u32(np, "bosch,slew-rate", &slew)) {
> > /* Determine default slew rate */
> > slew = (CLKOUT_SL_MASK >>
> > CLKOUT_SL_SHIFT) -
>
> Rob,
>
> The next few lines look like this:
>
> ((cdv * clkext - 1) / 8000000);
> if (slew < 0)
> slew = 0;
>
> But slew is now unsigned, so this check will always be false.
>
> Flagged by Smatch and Coccinelle.
Good finding.
Thanks,
Marc
--
Pengutronix e.K. | Marc Kleine-Budde |
Embedded Linux | https://www.pengutronix.de |
Vertretung Nürnberg | Phone: +49-5121-206917-129 |
Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-9 |
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^ permalink raw reply [flat|nested] 5+ messages in thread
* [PATCH] net: can: cc770: Simplify parsing DT properties
@ 2024-09-03 13:57 Rob Herring (Arm)
2024-09-04 9:52 ` Marc Kleine-Budde
0 siblings, 1 reply; 5+ messages in thread
From: Rob Herring (Arm) @ 2024-09-03 13:57 UTC (permalink / raw)
To: Simon Horman, Marc Kleine-Budde, Vincent Mailhol, David S. Miller,
Eric Dumazet, Jakub Kicinski, Paolo Abeni
Cc: linux-can, netdev, linux-kernel
Use of the typed property accessors is preferred over of_get_property().
The existing code doesn't work on little endian systems either. Replace
the of_get_property() calls with of_property_read_bool() and
of_property_read_u32().
Signed-off-by: Rob Herring (Arm) <robh@kernel.org>
---
v2:
- Use reverse xmas tree order
- Fix slew unsigned comparison
---
drivers/net/can/cc770/cc770_platform.c | 32 +++++++++-----------------
1 file changed, 11 insertions(+), 21 deletions(-)
diff --git a/drivers/net/can/cc770/cc770_platform.c b/drivers/net/can/cc770/cc770_platform.c
index 13bcfba05f18..f2424fe58612 100644
--- a/drivers/net/can/cc770/cc770_platform.c
+++ b/drivers/net/can/cc770/cc770_platform.c
@@ -70,17 +70,10 @@ static void cc770_platform_write_reg(const struct cc770_priv *priv, int reg,
static int cc770_get_of_node_data(struct platform_device *pdev,
struct cc770_priv *priv)
{
+ u32 clkext = CC770_PLATFORM_CAN_CLOCK, clkout = 0;
struct device_node *np = pdev->dev.of_node;
- const u32 *prop;
- int prop_size;
- u32 clkext;
-
- prop = of_get_property(np, "bosch,external-clock-frequency",
- &prop_size);
- if (prop && (prop_size == sizeof(u32)))
- clkext = *prop;
- else
- clkext = CC770_PLATFORM_CAN_CLOCK; /* default */
+
+ of_property_read_u32(np, "bosch,external-clock-frequency", &clkext);
priv->can.clock.freq = clkext;
/* The system clock may not exceed 10 MHz */
@@ -98,7 +91,7 @@ static int cc770_get_of_node_data(struct platform_device *pdev,
if (of_property_read_bool(np, "bosch,iso-low-speed-mux"))
priv->cpu_interface |= CPUIF_MUX;
- if (!of_get_property(np, "bosch,no-comperator-bypass", NULL))
+ if (!of_property_read_bool(np, "bosch,no-comperator-bypass"))
priv->bus_config |= BUSCFG_CBY;
if (of_property_read_bool(np, "bosch,disconnect-rx0-input"))
priv->bus_config |= BUSCFG_DR0;
@@ -109,25 +102,22 @@ static int cc770_get_of_node_data(struct platform_device *pdev,
if (of_property_read_bool(np, "bosch,polarity-dominant"))
priv->bus_config |= BUSCFG_POL;
- prop = of_get_property(np, "bosch,clock-out-frequency", &prop_size);
- if (prop && (prop_size == sizeof(u32)) && *prop > 0) {
- u32 cdv = clkext / *prop;
- int slew;
+ of_property_read_u32(np, "bosch,clock-out-frequency", &clkout);
+ if (clkout > 0) {
+ u32 cdv = clkext / clkout;
if (cdv > 0 && cdv < 16) {
+ u32 slew;
+
priv->cpu_interface |= CPUIF_CEN;
priv->clkout |= (cdv - 1) & CLKOUT_CD_MASK;
- prop = of_get_property(np, "bosch,slew-rate",
- &prop_size);
- if (prop && (prop_size == sizeof(u32))) {
- slew = *prop;
- } else {
+ if (of_property_read_u32(np, "bosch,slew-rate", &slew)) {
/* Determine default slew rate */
slew = (CLKOUT_SL_MASK >>
CLKOUT_SL_SHIFT) -
((cdv * clkext - 1) / 8000000);
- if (slew < 0)
+ if (slew > (CLKOUT_SL_MASK >> CLKOUT_SL_SHIFT))
slew = 0;
}
priv->clkout |= (slew << CLKOUT_SL_SHIFT) &
--
2.45.2
^ permalink raw reply related [flat|nested] 5+ messages in thread
* Re: [PATCH] net: can: cc770: Simplify parsing DT properties
2024-09-03 13:57 Rob Herring (Arm)
@ 2024-09-04 9:52 ` Marc Kleine-Budde
0 siblings, 0 replies; 5+ messages in thread
From: Marc Kleine-Budde @ 2024-09-04 9:52 UTC (permalink / raw)
To: Rob Herring (Arm)
Cc: Simon Horman, Vincent Mailhol, David S. Miller, Eric Dumazet,
Jakub Kicinski, Paolo Abeni, linux-can, netdev, linux-kernel
[-- Attachment #1: Type: text/plain, Size: 744 bytes --]
On 03.09.2024 08:57:30, Rob Herring (Arm) wrote:
> Use of the typed property accessors is preferred over of_get_property().
> The existing code doesn't work on little endian systems either. Replace
> the of_get_property() calls with of_property_read_bool() and
> of_property_read_u32().
>
> Signed-off-by: Rob Herring (Arm) <robh@kernel.org>
> ---
> v2:
> - Use reverse xmas tree order
> - Fix slew unsigned comparison
Added to linux-can-next.
Thanks,
Marc
--
Pengutronix e.K. | Marc Kleine-Budde |
Embedded Linux | https://www.pengutronix.de |
Vertretung Nürnberg | Phone: +49-5121-206917-129 |
Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-9 |
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2024-08-28 13:19 [PATCH] net: can: cc770: Simplify parsing DT properties Rob Herring (Arm)
2024-08-28 16:16 ` Simon Horman
2024-08-29 19:35 ` Marc Kleine-Budde
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2024-09-04 9:52 ` Marc Kleine-Budde
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