[PATCH v5] pinctrl: stm32: Add check for clk_enable()

[PATCH v5] pinctrl: stm32: Add check for clk_enable()

[Mingwei Zheng]

Convert the driver to clk_bulk*() API.
Add check for the return value of clk_bulk_enable() to catch
the potential error.

Fixes: 05d8af449d93 ("pinctrl: stm32: Keep pinctrl block clock enabled when LEVEL IRQ requested")
Signed-off-by: Mingwei Zheng <zmw12306@gmail.com>
Signed-off-by: Jiasheng Jiang <jiashengjiangcool@gmail.com>
---
Changelog:

v4 -> v5:
1. Move the clock handling from stm32_gpiolib_register_bank() 
and moving it to its caller.
2. Call clk_bulk_prepare_enable() in stm32_pctl_probe() 
and clk_bulk_disable_unprepare() for error.

v3 -> v4:
1. Add initialization for  pctl->clks.
2. Adjust alignment.

v2 -> v3:

1. Convert clk_disable_unprepare to clk_bulk_disable
and clk_bulk_unprepare.

v1 -> v2:

1. Move int ret declaration into if block.
---
 drivers/pinctrl/stm32/pinctrl-stm32.c | 70 ++++++++++++---------------
 1 file changed, 32 insertions(+), 38 deletions(-)

diff --git a/drivers/pinctrl/stm32/pinctrl-stm32.c b/drivers/pinctrl/stm32/pinctrl-stm32.c
index 5b7fa77c1184..5874a054dc48 100644
--- a/drivers/pinctrl/stm32/pinctrl-stm32.c
+++ b/drivers/pinctrl/stm32/pinctrl-stm32.c
@@ -86,7 +86,6 @@ struct stm32_pinctrl_group {
 
 struct stm32_gpio_bank {
 	void __iomem *base;
-	struct clk *clk;
 	struct reset_control *rstc;
 	spinlock_t lock;
 	struct gpio_chip gpio_chip;
@@ -108,6 +107,7 @@ struct stm32_pinctrl {
 	unsigned ngroups;
 	const char **grp_names;
 	struct stm32_gpio_bank *banks;
+	struct clk_bulk_data *clks;
 	unsigned nbanks;
 	const struct stm32_pinctrl_match_data *match_data;
 	struct irq_domain	*domain;
@@ -1308,12 +1308,6 @@ static int stm32_gpiolib_register_bank(struct stm32_pinctrl *pctl, struct fwnode
 	if (IS_ERR(bank->base))
 		return PTR_ERR(bank->base);
 
-	err = clk_prepare_enable(bank->clk);
-	if (err) {
-		dev_err(dev, "failed to prepare_enable clk (%d)\n", err);
-		return err;
-	}
-
 	bank->gpio_chip = stm32_gpio_template;
 
 	fwnode_property_read_string(fwnode, "st,bank-name", &bank->gpio_chip.label);
@@ -1360,26 +1354,21 @@ static int stm32_gpiolib_register_bank(struct stm32_pinctrl *pctl, struct fwnode
 							   bank->fwnode, &stm32_gpio_domain_ops,
 							   bank);
 
-		if (!bank->domain) {
-			err = -ENODEV;
-			goto err_clk;
-		}
+		if (!bank->domain)
+			return -ENODEV;
 	}
 
 	names = devm_kcalloc(dev, npins, sizeof(char *), GFP_KERNEL);
-	if (!names) {
-		err = -ENOMEM;
-		goto err_clk;
-	}
+	if (!names)
+		return -ENOMEM;
 
 	for (i = 0; i < npins; i++) {
 		stm32_pin = stm32_pctrl_get_desc_pin_from_gpio(pctl, bank, i);
 		if (stm32_pin && stm32_pin->pin.name) {
 			names[i] = devm_kasprintf(dev, GFP_KERNEL, "%s", stm32_pin->pin.name);
-			if (!names[i]) {
-				err = -ENOMEM;
-				goto err_clk;
-			}
+			if (!names[i])
+				return -ENOMEM;
+
 		} else {
 			names[i] = NULL;
 		}
@@ -1390,15 +1379,11 @@ static int stm32_gpiolib_register_bank(struct stm32_pinctrl *pctl, struct fwnode
 	err = gpiochip_add_data(&bank->gpio_chip, bank);
 	if (err) {
 		dev_err(dev, "Failed to add gpiochip(%d)!\n", bank_nr);
-		goto err_clk;
+		return err;
 	}
 
 	dev_info(dev, "%s bank added\n", bank->gpio_chip.label);
 	return 0;
-
-err_clk:
-	clk_disable_unprepare(bank->clk);
-	return err;
 }
 
 static struct irq_domain *stm32_pctrl_get_irq_domain(struct platform_device *pdev)
@@ -1617,10 +1602,18 @@ int stm32_pctl_probe(struct platform_device *pdev)
 		return -EINVAL;
 	}
 	pctl->banks = devm_kcalloc(dev, banks, sizeof(*pctl->banks),
-			GFP_KERNEL);
+				   GFP_KERNEL);
 	if (!pctl->banks)
 		return -ENOMEM;
 
+	pctl->clks = devm_kcalloc(dev, banks, sizeof(*pctl->clks),
+				  GFP_KERNEL);
+	if (!pctl->clks)
+		return -ENOMEM;
+
+	for (i = 0; i < banks; ++i)
+		pctl->clks[i].id = "";
+
 	i = 0;
 	for_each_gpiochip_node(dev, child) {
 		struct stm32_gpio_bank *bank = &pctl->banks[i];
@@ -1631,11 +1624,10 @@ int stm32_pctl_probe(struct platform_device *pdev)
 			fwnode_handle_put(child);
 			return -EPROBE_DEFER;
 		}
-
-		bank->clk = of_clk_get_by_name(np, NULL);
-		if (IS_ERR(bank->clk)) {
+		pctl->clks[i].clk = of_clk_get_by_name(np, NULL);
+		if (IS_ERR(pctl->clks[i].clk)) {
 			fwnode_handle_put(child);
-			return dev_err_probe(dev, PTR_ERR(bank->clk),
+			return dev_err_probe(dev, PTR_ERR(pctl->clks[i].clk),
 					     "failed to get clk\n");
 		}
 		i++;
@@ -1646,15 +1638,18 @@ int stm32_pctl_probe(struct platform_device *pdev)
 		if (ret) {
 			fwnode_handle_put(child);
 
-			for (i = 0; i < pctl->nbanks; i++)
-				clk_disable_unprepare(pctl->banks[i].clk);
-
 			return ret;
 		}
 
 		pctl->nbanks++;
 	}
 
+	ret = clk_bulk_prepare_enable(pctl->nbanks, pctl->clks);
+	if (ret) {
+		dev_err(dev, "failed to prepare_enable clk (%d)\n", ret);
+		return ret;
+	}
+
 	dev_info(dev, "Pinctrl STM32 initialized\n");
 
 	return 0;
@@ -1726,10 +1721,8 @@ static int __maybe_unused stm32_pinctrl_restore_gpio_regs(
 int __maybe_unused stm32_pinctrl_suspend(struct device *dev)
 {
 	struct stm32_pinctrl *pctl = dev_get_drvdata(dev);
-	int i;
 
-	for (i = 0; i < pctl->nbanks; i++)
-		clk_disable(pctl->banks[i].clk);
+	clk_bulk_disable(pctl->nbanks, pctl->clks);
 
 	return 0;
 }
@@ -1738,10 +1731,11 @@ int __maybe_unused stm32_pinctrl_resume(struct device *dev)
 {
 	struct stm32_pinctrl *pctl = dev_get_drvdata(dev);
 	struct stm32_pinctrl_group *g = pctl->groups;
-	int i;
+	int i, ret;
 
-	for (i = 0; i < pctl->nbanks; i++)
-		clk_enable(pctl->banks[i].clk);
+	ret = clk_bulk_enable(pctl->nbanks, pctl->clks);
+	if (ret)
+		return ret;
 
 	for (i = 0; i < pctl->ngroups; i++, g++)
 		stm32_pinctrl_restore_gpio_regs(pctl, g->pin);
-- 
2.34.1

Re: [PATCH v5] pinctrl: stm32: Add check for clk_enable()

[Marek Vasut]

On 12/15/24 9:40 PM, Mingwei Zheng wrote:

[...]

> @@ -1617,10 +1602,18 @@ int stm32_pctl_probe(struct platform_device *pdev)
>   		return -EINVAL;
>   	}
>   	pctl->banks = devm_kcalloc(dev, banks, sizeof(*pctl->banks),
> -			GFP_KERNEL);
> +				   GFP_KERNEL);

Please drop this one change.

>   	if (!pctl->banks)
>   		return -ENOMEM;
>   
> +	pctl->clks = devm_kcalloc(dev, banks, sizeof(*pctl->clks),
> +				  GFP_KERNEL);
> +	if (!pctl->clks)
> +		return -ENOMEM;
> +
> +	for (i = 0; i < banks; ++i)
> +		pctl->clks[i].id = "";

Is this ^ assignment necessary ? If so, why ?

[...]

Re: [PATCH v5] pinctrl: stm32: Add check for clk_enable()

[Mingwei Zheng]

Hi Marek,

On Sun, Dec 15, 2024 at 6:54 PM Marek Vasut <marex@denx.de> wrote:
>
> On 12/15/24 9:40 PM, Mingwei Zheng wrote:
>
> [...]
>
> > @@ -1617,10 +1602,18 @@ int stm32_pctl_probe(struct platform_device *pdev)
> >               return -EINVAL;
> >       }
> >       pctl->banks = devm_kcalloc(dev, banks, sizeof(*pctl->banks),
> > -                     GFP_KERNEL);
> > +                                GFP_KERNEL);
>
> Please drop this one change.

Fixed in PATCH v6.

>
> >       if (!pctl->banks)
> >               return -ENOMEM;
> >
> > +     pctl->clks = devm_kcalloc(dev, banks, sizeof(*pctl->clks),
> > +                               GFP_KERNEL);
> > +     if (!pctl->clks)
> > +             return -ENOMEM;
> > +
> > +     for (i = 0; i < banks; ++i)
> > +             pctl->clks[i].id = "";
>
> Is this ^ assignment necessary ? If so, why ?
>
> [...]

Thanks for pointing this out. We call devm_clk_bulk_get_all in
stm32_pctl_probe() to handle get clk in PATCH v6.

Best,
Mingwei

Re: [PATCH v5] pinctrl: stm32: Add check for clk_enable()

[Antonio Borneo]

On Mon, 2024-12-16 at 00:41 +0100, Marek Vasut wrote:
> On 12/15/24 9:40 PM, Mingwei Zheng wrote:
> 
> [...]
> 
> > @@ -1617,10 +1602,18 @@ int stm32_pctl_probe(struct platform_device *pdev)
> >                 return -EINVAL;
> >         }
> >         pctl->banks = devm_kcalloc(dev, banks, sizeof(*pctl->banks),
> > -                       GFP_KERNEL);
> > +                                  GFP_KERNEL);
> 
> Please drop this one change.
> 
> >         if (!pctl->banks)
> >                 return -ENOMEM;
> >   
> > +       pctl->clks = devm_kcalloc(dev, banks, sizeof(*pctl->clks),
> > +                                 GFP_KERNEL);
> > +       if (!pctl->clks)
> > +               return -ENOMEM;
> > +
> > +       for (i = 0; i < banks; ++i)
> > +               pctl->clks[i].id = "";
> 
> Is this ^ assignment necessary ? If so, why ?

The existing DTs don't have the 'clock-names' property, whose value is used to set this struct clk_bulk_data::id.
With this field kept at NULL, the error messages in clk_bulk_enable() and similar should print '(null)'.
This line sets it to empty string.
I would say it's not necessary, but I don't know if it's better to have:
"Failed to enable clk '': %d"
or
"Failed to enable clk '(null)': %d"

Antonio