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@xxxxxxxxxx>
...
> 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.
