Use platform_irq_count to determine the number of fan tachometer inputs
configured in the device tree. At this stage we support either 0 or 1
inputs.
Once we have this information we only need to read the
pulses-per-revolution value if a fan tachometer is actually configured
via an IRQ value.
Also add a debug print of the IRQ number and the pulses-per-revolution
value to aid in investigating issues.
Signed-off-by: Paul Barker <pbarker@xxxxxxxxxxxx>
Reviewed-by: Guenter Roeck <linux@xxxxxxxxxxxx>
---
drivers/hwmon/pwm-fan.c | 50 +++++++++++++++++++++++++++--------------
1 file changed, 33 insertions(+), 17 deletions(-)
diff --git a/drivers/hwmon/pwm-fan.c b/drivers/hwmon/pwm-fan.c
index 1f63807c0399..efe2764f42d3 100644
--- a/drivers/hwmon/pwm-fan.c
+++ b/drivers/hwmon/pwm-fan.c
@@ -286,7 +286,7 @@ static int pwm_fan_probe(struct platform_device *pdev)
struct device *hwmon;
int ret;
struct pwm_state state = { };
- u32 ppr = 2;
+ int tach_count;
ctx = devm_kzalloc(dev, sizeof(*ctx), GFP_KERNEL);
if (!ctx)
@@ -300,10 +300,6 @@ static int pwm_fan_probe(struct platform_device *pdev)
platform_set_drvdata(pdev, ctx);
- ctx->irq = platform_get_irq_optional(pdev, 0);
- if (ctx->irq == -EPROBE_DEFER)
- return ctx->irq;
-
ctx->reg_en = devm_regulator_get_optional(dev, "fan");
if (IS_ERR(ctx->reg_en)) {
if (PTR_ERR(ctx->reg_en) != -ENODEV)
@@ -339,20 +335,40 @@ static int pwm_fan_probe(struct platform_device *pdev)
if (ret)
return ret;
- of_property_read_u32(dev->of_node, "pulses-per-revolution", &ppr);
- ctx->pulses_per_revolution = ppr;
- if (!ctx->pulses_per_revolution) {
- dev_err(dev, "pulses-per-revolution can't be zero.\n");
- return -EINVAL;
- }
+ tach_count = platform_irq_count(pdev);
+ if (tach_count < 0)
+ return dev_err_probe(dev, tach_count,
+ "Could not get number of fan tachometer inputs\n");
+
+ if (tach_count > 0) {
+ u32 ppr = 2;
+
+ ctx->irq = platform_get_irq(pdev, 0);
+ if (ctx->irq == -EPROBE_DEFER)
+ return ctx->irq;
+ if (ctx->irq > 0) {
+ ret = devm_request_irq(dev, ctx->irq, pulse_handler, 0,
+ pdev->name, ctx);
+ if (ret) {
+ dev_err(dev,
+ "Failed to request interrupt: %d\n",
+ ret);
+ return ret;
+ }
+ }
- if (ctx->irq > 0) {
- ret = devm_request_irq(dev, ctx->irq, pulse_handler, 0,
- pdev->name, ctx);
- if (ret) {
- dev_err(dev, "Failed to request interrupt: %d\n", ret);
- return ret;
+ of_property_read_u32(dev->of_node,
+ "pulses-per-revolution",
+ &ppr);
+ ctx->pulses_per_revolution = ppr;
+ if (!ctx->pulses_per_revolution) {
+ dev_err(dev, "pulses-per-revolution can't be zero.\n");
+ return -EINVAL;
}
+
+ dev_dbg(dev, "tach: irq=%d, pulses_per_revolution=%d\n",
+ ctx->irq, ctx->pulses_per_revolution);
+
ctx->sample_start = ktime_get();
mod_timer(&ctx->rpm_timer, jiffies + HZ);
}
--
2.26.2
