diff mbox series

[v2,2/4] gpio: sifive: Look up IRQs only once during probe

Message ID 20230719163446.1398961-3-samuel.holland@sifive.com
State Accepted
Commit 1cd9cee75f99cfe31a6e339af518679649812838
Headers show
Series gpio: sifive: Module support | expand

Commit Message

Samuel Holland July 19, 2023, 4:34 p.m. UTC
of_irq_count(), or eqivalently platform_irq_count(), simply looks up
successively-numbered IRQs until that fails. Since this driver needs to
look up each IRQ anyway to get its virq number, use that existing loop
to count the IRQs at the same time.

Signed-off-by: Samuel Holland <samuel.holland@sifive.com>
---

Changes in v2:
 - New patch for v2

 drivers/gpio/gpio-sifive.c | 17 +++++------------
 1 file changed, 5 insertions(+), 12 deletions(-)

Comments

Samuel Holland July 19, 2023, 4:55 p.m. UTC | #1
On 2023-07-19 11:48 AM, Andy Shevchenko wrote:
> On Wed, Jul 19, 2023 at 09:34:43AM -0700, Samuel Holland wrote:
>> of_irq_count(), or eqivalently platform_irq_count(), simply looks up
>> successively-numbered IRQs until that fails. Since this driver needs to
>> look up each IRQ anyway to get its virq number, use that existing loop
>> to count the IRQs at the same time.
> 
> ...
> 
>> -	ngpio = of_irq_count(node);
>> -	if (ngpio > SIFIVE_GPIO_MAX) {
>> -		dev_err(dev, "Too many GPIO interrupts (max=%d)\n",
>> -			SIFIVE_GPIO_MAX);
>> -		return -ENXIO;
> 
> Do we still need this check?

I don't think so. I think this check was only intended to prevent overflowing
the irq_number array, and that is now handled by the loop condition.

>> -	}
> 
> ...
> 
>> +	for (ngpio = 0; ngpio < SIFIVE_GPIO_MAX; ngpio++) {
>> +		ret = platform_get_irq_optional(pdev, ngpio);
>>  		if (ret < 0)
>> -			return ret;
>> -		chip->irq_number[i] = ret;
>> +			break;
>> +		chip->irq_number[ngpio] = ret;
>>  	}
> 
> If so, here we need something like
> 
> 	ret = platform_get_irq_optional(pdev, ngpio);
> 	if (ret > 0) {
> 		dev_err(dev, "Too many GPIO interrupts (max=%d)\n",
> 			SIFIVE_GPIO_MAX);
> 		return -ENXIO;
> 	}
> 
> Otherwise you need to mention this relaxation in the commit message.

OK, I will add something to the commit message in v3.
diff mbox series

Patch

diff --git a/drivers/gpio/gpio-sifive.c b/drivers/gpio/gpio-sifive.c
index ab32c952c61b..6606c919d957 100644
--- a/drivers/gpio/gpio-sifive.c
+++ b/drivers/gpio/gpio-sifive.c
@@ -185,7 +185,7 @@  static int sifive_gpio_probe(struct platform_device *pdev)
 	struct irq_domain *parent;
 	struct gpio_irq_chip *girq;
 	struct sifive_gpio *chip;
-	int ret, ngpio, i;
+	int ret, ngpio;
 
 	chip = devm_kzalloc(dev, sizeof(*chip), GFP_KERNEL);
 	if (!chip)
@@ -202,13 +202,6 @@  static int sifive_gpio_probe(struct platform_device *pdev)
 	if (IS_ERR(chip->regs))
 		return PTR_ERR(chip->regs);
 
-	ngpio = of_irq_count(node);
-	if (ngpio > SIFIVE_GPIO_MAX) {
-		dev_err(dev, "Too many GPIO interrupts (max=%d)\n",
-			SIFIVE_GPIO_MAX);
-		return -ENXIO;
-	}
-
 	irq_parent = of_irq_find_parent(node);
 	if (!irq_parent) {
 		dev_err(dev, "no IRQ parent node\n");
@@ -221,11 +214,11 @@  static int sifive_gpio_probe(struct platform_device *pdev)
 		return -ENODEV;
 	}
 
-	for (i = 0; i < ngpio; i++) {
-		ret = platform_get_irq(pdev, i);
+	for (ngpio = 0; ngpio < SIFIVE_GPIO_MAX; ngpio++) {
+		ret = platform_get_irq_optional(pdev, ngpio);
 		if (ret < 0)
-			return ret;
-		chip->irq_number[i] = ret;
+			break;
+		chip->irq_number[ngpio] = ret;
 	}
 
 	ret = bgpio_init(&chip->gc, dev, 4,