Re: [PATCH 1/2] serial: msm-geni: allow invalid clock

[Sumit Garg <sumit.garg@kernel.org>]

On Fri, Mar 20, 2026 at 04:45:40PM +0100, Casey Connolly via B4 Relay wrote:
> From: Casey Connolly <casey.connolly@linaro.org>
> 
> Pre-relocation we probably won't have a clock but it's usually
> been enabled for us already, or worst case we will enable it after
> relocation.
> 

Not sure if this is the right approach, since the UART driver might just
hang without clock being enabled. What's the motivation for this change?

-Sumit

> Signed-off-by: Casey Connolly <casey.connolly@linaro.org>
> ---
>  drivers/serial/serial_msm_geni.c | 15 +++++----------
>  1 file changed, 5 insertions(+), 10 deletions(-)
> 
> diff --git a/drivers/serial/serial_msm_geni.c b/drivers/serial/serial_msm_geni.c
> index bb5a2cb4d2cd..c37255f57d05 100644
> --- a/drivers/serial/serial_msm_geni.c
> +++ b/drivers/serial/serial_msm_geni.c
> @@ -211,9 +211,9 @@ static int msm_serial_setbrg(struct udevice *dev, int baud)
>  	}
>  	ret = clk_set_rate(priv->se, clk_rate);
>  	if (ret < 0) {
>  		pr_err("%s: Couldn't set clock rate: %d\n", __func__, ret);
> -		return ret;
> +		return 0;
>  	}
>  	geni_serial_baud(priv->base, clk_div, baud);
>  
>  	return 0;
> @@ -516,15 +516,14 @@ static int msm_serial_probe(struct udevice *dev)
>  	int ret;
>  	u32 proto;
>  	struct clk *clk;
>  
> -	clk = devm_clk_get(dev, NULL);
> -	if (IS_ERR(clk))
> -		return PTR_ERR(clk);
> -	priv->se = clk;
> +	clk = devm_clk_get_optional(dev, NULL);
> +	if (!IS_ERR(clk))
> +		priv->se = clk;
>  
>  	/* Try enable clock */
> -	ret = clk_enable(clk);
> +	clk_enable(clk);
>  
>  	/* Check if firmware loading is needed (BT UART) */
>  	proto = readl(priv->base + GENI_FW_REVISION_RO);
>  	proto &= FW_REV_PROTOCOL_MSK;
> @@ -546,12 +545,8 @@ static int msm_serial_probe(struct udevice *dev)
>  	/* Don't actually probe non-debug UARTs */
>  	if (ofnode_device_is_compatible(dev_ofnode(dev), "qcom,geni-uart"))
>  		return -ENOENT;
>  
> -	/* Now handle clock enable return value */
> -	if (ret)
> -		return ret;
> -
>  	ret = geni_set_oversampling(dev);
>  	if (ret < 0)
>  		return ret;
>  
> 
> -- 
> 2.51.0
> 
>