2023-10-05 14:36:24

by Andy Shevchenko

Subject: [PATCH v2 1/1] serial: 8250_bcm7271: Use devm_clk_get_optional_enabled()

Use devm_clk_get_optional_enabled() to simplify the code.

Signed-off-by: Andy Shevchenko <[email protected]>
---
v2: fixed the returned value (Andi)
drivers/tty/serial/8250/8250_bcm7271.c | 24 +++++++++---------------
1 file changed, 9 insertions(+), 15 deletions(-)

diff --git a/drivers/tty/serial/8250/8250_bcm7271.c b/drivers/tty/serial/8250/8250_bcm7271.c
index 1a853a08654a..55dea2539c47 100644
--- a/drivers/tty/serial/8250/8250_bcm7271.c
+++ b/drivers/tty/serial/8250/8250_bcm7271.c
@@ -1015,26 +1015,23 @@ static int brcmuart_probe(struct platform_device *pdev)
of_property_read_u32(np, "clock-frequency", &clk_rate);

/* See if a Baud clock has been specified */
- baud_mux_clk = devm_clk_get(dev, "sw_baud");
- if (IS_ERR(baud_mux_clk)) {
- if (PTR_ERR(baud_mux_clk) == -EPROBE_DEFER) {
- ret = -EPROBE_DEFER;
- goto release_dma;
- }
- dev_dbg(dev, "BAUD MUX clock not specified\n");
- } else {
+ baud_mux_clk = devm_clk_get_optional_enabled(dev, "sw_baud");
+ ret = PTR_ERR_OR_ZERO(baud_mux_clk);
+ if (ret)
+ goto release_dma;
+ if (baud_mux_clk) {
dev_dbg(dev, "BAUD MUX clock found\n");
- ret = clk_prepare_enable(baud_mux_clk);
- if (ret)
- goto release_dma;
+
priv->baud_mux_clk = baud_mux_clk;
init_real_clk_rates(dev, priv);
clk_rate = priv->default_mux_rate;
+ } else {
+ dev_dbg(dev, "BAUD MUX clock not specified\n");
}

if (clk_rate == 0) {
ret = dev_err_probe(dev, -EINVAL, "clock-frequency or clk not defined\n");
- goto err_clk_disable;
+ goto release_dma;
}

dev_dbg(dev, "DMA is %senabled\n", priv->dma_enabled ? "" : "not ");
@@ -1118,8 +1115,6 @@ static int brcmuart_probe(struct platform_device *pdev)
serial8250_unregister_port(priv->line);
err:
brcmuart_free_bufs(dev, priv);
-err_clk_disable:
- clk_disable_unprepare(baud_mux_clk);
release_dma:
if (priv->dma_enabled)
brcmuart_arbitration(priv, 0);
@@ -1134,7 +1129,6 @@ static int brcmuart_remove(struct platform_device *pdev)
hrtimer_cancel(&priv->hrt);
serial8250_unregister_port(priv->line);
brcmuart_free_bufs(&pdev->dev, priv);
- clk_disable_unprepare(priv->baud_mux_clk);
if (priv->dma_enabled)
brcmuart_arbitration(priv, 0);
return 0;
--
2.40.0.1.gaa8946217a0b

2023-10-05 16:01:43

by Andi Shyti

Subject: Re: [PATCH v2 1/1] serial: 8250_bcm7271: Use devm_clk_get_optional_enabled()

Hi Andy,

[...]

> - baud_mux_clk = devm_clk_get(dev, "sw_baud");
> - if (IS_ERR(baud_mux_clk)) {
> - if (PTR_ERR(baud_mux_clk) == -EPROBE_DEFER) {
> - ret = -EPROBE_DEFER;
> - goto release_dma;
> - }
> - dev_dbg(dev, "BAUD MUX clock not specified\n");
> - } else {
> + baud_mux_clk = devm_clk_get_optional_enabled(dev, "sw_baud");
> + ret = PTR_ERR_OR_ZERO(baud_mux_clk);
> + if (ret)
> + goto release_dma;
> + if (baud_mux_clk) {
> dev_dbg(dev, "BAUD MUX clock found\n");
> - ret = clk_prepare_enable(baud_mux_clk);
> - if (ret)
> - goto release_dma;
> +
> priv->baud_mux_clk = baud_mux_clk;
> init_real_clk_rates(dev, priv);
> clk_rate = priv->default_mux_rate;
> + } else {
> + dev_dbg(dev, "BAUD MUX clock not specified\n");

little behavioral change here, but I don't think this is a
problem.

Reviewed-by: Andi Shyti <[email protected]>

Thanks,
Andi

2023-10-05 16:17:47

by Andy Shevchenko

Subject: Re: [PATCH v2 1/1] serial: 8250_bcm7271: Use devm_clk_get_optional_enabled()

On Thu, Oct 05, 2023 at 05:19:38PM +0200, Andi Shyti wrote:

[...]

> > - baud_mux_clk = devm_clk_get(dev, "sw_baud");
> > - if (IS_ERR(baud_mux_clk)) {
> > - if (PTR_ERR(baud_mux_clk) == -EPROBE_DEFER) {
> > - ret = -EPROBE_DEFER;
> > - goto release_dma;
> > - }
> > - dev_dbg(dev, "BAUD MUX clock not specified\n");
> > - } else {
> > + baud_mux_clk = devm_clk_get_optional_enabled(dev, "sw_baud");
> > + ret = PTR_ERR_OR_ZERO(baud_mux_clk);
> > + if (ret)
> > + goto release_dma;
> > + if (baud_mux_clk) {
> > dev_dbg(dev, "BAUD MUX clock found\n");
> > - ret = clk_prepare_enable(baud_mux_clk);
> > - if (ret)
> > - goto release_dma;
> > +
> > priv->baud_mux_clk = baud_mux_clk;
> > init_real_clk_rates(dev, priv);
> > clk_rate = priv->default_mux_rate;
> > + } else {
> > + dev_dbg(dev, "BAUD MUX clock not specified\n");
>
> little behavioral change here, but I don't think this is a
> problem.

You meant that "if (!x) else" had been changed to "if (x) else" semantics?
Otherwise I don't see any difference.

> Reviewed-by: Andi Shyti <[email protected]>

Thank you!

--
With Best Regards,
Andy Shevchenko

2023-10-05 16:41:36

by Andi Shyti

Subject: Re: [PATCH v2 1/1] serial: 8250_bcm7271: Use devm_clk_get_optional_enabled()

Hi Andy,

On Thu, Oct 05, 2023 at 06:37:16PM +0300, Andy Shevchenko wrote:
> On Thu, Oct 05, 2023 at 05:19:38PM +0200, Andi Shyti wrote:
>
> [...]
>
> > > - baud_mux_clk = devm_clk_get(dev, "sw_baud");
> > > - if (IS_ERR(baud_mux_clk)) {
> > > - if (PTR_ERR(baud_mux_clk) == -EPROBE_DEFER) {
> > > - ret = -EPROBE_DEFER;
> > > - goto release_dma;
> > > - }
> > > - dev_dbg(dev, "BAUD MUX clock not specified\n");
> > > - } else {
> > > + baud_mux_clk = devm_clk_get_optional_enabled(dev, "sw_baud");
> > > + ret = PTR_ERR_OR_ZERO(baud_mux_clk);
> > > + if (ret)
> > > + goto release_dma;
> > > + if (baud_mux_clk) {
> > > dev_dbg(dev, "BAUD MUX clock found\n");
> > > - ret = clk_prepare_enable(baud_mux_clk);
> > > - if (ret)
> > > - goto release_dma;
> > > +
> > > priv->baud_mux_clk = baud_mux_clk;
> > > init_real_clk_rates(dev, priv);
> > > clk_rate = priv->default_mux_rate;
> > > + } else {
> > > + dev_dbg(dev, "BAUD MUX clock not specified\n");
> >
> > little behavioral change here, but I don't think this is a
> > problem.
>
> You meant that "if (!x) else" had been changed to "if (x) else" semantics?
> Otherwise I don't see any difference.

If devm_clk_get() fails with anything but -EPROBE_DEFER
originally the code was not returning, while now it returns.

But still... this is perfectly fine.

Andi

> > Reviewed-by: Andi Shyti <[email protected]>
>
> Thank you!
>
> --
> With Best Regards,
> Andy Shevchenko
>