[PATCH v4 1/3] pps: clients: gpio: propagate probe error codes

[Eliav Farber]

On the two probe error paths that map and request the interrupt, probe
overwrote the error from gpiod_to_irq() and request_threaded_irq() with a
hardcoded -EINVAL, hiding meaningful codes such as -EBUSY, -ENOMEM or
-EPROBE_DEFER from the caller. The request_threaded_irq() failure message
also logged the IRQ number but not the errno.

Return the actual error code from both paths, and add the errno to the
request_threaded_irq() failure message.

Fixes: 161520451dfa ("pps: new client driver using GPIO")
Signed-off-by: Eliav Farber <farbere@xxxxxxxxxx>
Reviewed-by: Bartosz Golaszewski <bartosz.golaszewski@xxxxxxxxxxxxxxxx>
---
Changes in v4:
- Add Fixes: 161520451dfa ("pps: new client driver using GPIO") and
  Bartosz Golaszewski's Reviewed-by. The hardcoded -EINVAL on both error
  paths predates 4461d65176b4 (which only switched gpio_to_irq() to
  gpiod_to_irq() and left those returns as context), so the tag points at
  the original driver rather than the descriptor conversion

Changes in v3:
- New patch, split out of the pinctrl change: while converting the probe
  error paths to a goto, Takashi Sakamoto noted that the hardcoded -EINVAL
  discards the real gpiod_to_irq()/request_threaded_irq() error, so fix
  that separately first

 drivers/pps/clients/pps-gpio.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/pps/clients/pps-gpio.c b/drivers/pps/clients/pps-gpio.c
index 73ec2c7335e5..038c55c5f7d4 100644
--- a/drivers/pps/clients/pps-gpio.c
+++ b/drivers/pps/clients/pps-gpio.c
@@ -165,7 +165,7 @@ static int pps_gpio_probe(struct platform_device *pdev)
 	ret = gpiod_to_irq(data->gpio_pin);
 	if (ret < 0) {
 		dev_err(dev, "failed to map GPIO to IRQ: %d\n", ret);
-		return -EINVAL;
+		return ret;
 	}
 	data->irq = ret;
 
@@ -197,8 +197,8 @@ static int pps_gpio_probe(struct platform_device *pdev)
 			  data->info.name, data);
 	if (ret) {
 		pps_unregister_source(data->pps);
-		dev_err(dev, "failed to acquire IRQ %d\n", data->irq);
-		return -EINVAL;
+		dev_err(dev, "failed to acquire IRQ %d: %d\n", data->irq, ret);
+		return ret;
 	}
 
 	dev_dbg(&data->pps->dev, "Registered IRQ %d as PPS source\n",
-- 
2.47.3