Re: [PATCH 1/3] i2c: bcm2835: Use platform_get_irq() to get the interrupt

From: Florian Fainelli
Date: Sat Dec 18 2021 - 16:17:20 EST




On 12/18/2021 8:52 AM, Lad Prabhakar wrote:
platform_get_resource(pdev, IORESOURCE_IRQ, ..) relies on static
allocation of IRQ resources in DT core code, this causes an issue
when using hierarchical interrupt domains using "interrupts" property
in the node as this bypasses the hierarchical setup and messes up the
irq chaining.

In preparation for removal of static setup of IRQ resource from DT core
code use platform_get_irq().

Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@xxxxxxxxxxxxxx>

Just one nit below:
---
drivers/i2c/busses/i2c-bcm2835.c | 11 ++++-------
1 file changed, 4 insertions(+), 7 deletions(-)

diff --git a/drivers/i2c/busses/i2c-bcm2835.c b/drivers/i2c/busses/i2c-bcm2835.c
index 37443edbf754..d63dec5f3cb1 100644
--- a/drivers/i2c/busses/i2c-bcm2835.c
+++ b/drivers/i2c/busses/i2c-bcm2835.c
@@ -402,7 +402,7 @@ static const struct i2c_adapter_quirks bcm2835_i2c_quirks = {
static int bcm2835_i2c_probe(struct platform_device *pdev)
{
struct bcm2835_i2c_dev *i2c_dev;
- struct resource *mem, *irq;
+ struct resource *mem;
int ret;
struct i2c_adapter *adap;
struct clk *mclk;
@@ -452,12 +452,9 @@ static int bcm2835_i2c_probe(struct platform_device *pdev)
return ret;
}
- irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
- if (!irq) {
- dev_err(&pdev->dev, "No IRQ resource\n");
- return -ENODEV;
- }
- i2c_dev->irq = irq->start;
+ i2c_dev->irq = platform_get_irq(pdev, 0);
+ if (i2c_dev->irq <= 0)
+ return i2c_dev->irq ? i2c_dev->irq : -ENXIO;

Why not just check for a negative return code and propagate it as is?
--
Florian