Re: [PATCH v4 4/5] wifi: brcmfmac: Add optional lpo clock enable support

[Dragan Simic]

Hello Jacobe,

Please see one comment below.

On 2024-07-29 09:01, Jacobe Zang wrote:
> WiFi modules often require 32kHz clock to function. Add support to
> enable the clock to PCIe driver.
>
> Co-developed-by: Ondrej Jirman <megi@xxxxxx>
> Signed-off-by: Ondrej Jirman <megi@xxxxxx>
> Signed-off-by: Jacobe Zang <jacobe.zang@xxxxxxxxxx>
> ---
>  drivers/net/wireless/broadcom/brcm80211/brcmfmac/of.c | 9 +++++++++
>  1 file changed, 9 insertions(+)
>
> diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/of.c
> b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/of.c
> index e406e11481a62..4db188a41fd52 100644
> --- a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/of.c
> +++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/of.c
> @@ -6,6 +6,7 @@
>  #include <linux/of.h>
>  #include <linux/of_irq.h>
>  #include <linux/of_net.h>
> +#include <linux/clk.h>
>
>  #include <defs.h>
>  #include "debug.h"
> @@ -70,6 +71,7 @@ void brcmf_of_probe(struct device *dev, enum
> brcmf_bus_type bus_type,
>  {
>  	struct brcmfmac_sdio_pd *sdio = &settings->bus.sdio;
>  	struct device_node *root, *np = dev->of_node;
> +	struct clk *clk;
>  	const char *prop;
>  	int irq;
>  	int err;
> @@ -113,6 +115,13 @@ void brcmf_of_probe(struct device *dev, enum
> brcmf_bus_type bus_type,
>  		of_node_put(root);
>  	}
>
> +	clk = devm_clk_get_optional_enabled(dev, "lpo");
> +	if (IS_ERR(clk))
> +	if (clk) {

These two lines looks really confusing.  Shouldn't it be just a single
"if (!IS_ERR(clk)) {" line instead?

> +		brcmf_dbg(INFO, "enabling 32kHz clock\n");
> +		clk_set_rate(clk, 32768);
> +	}
> +
>  	if (!np || !of_device_is_compatible(np, "brcm,bcm4329-fmac"))
>  		return;