hwmon: (lm90) Add support to handle IRQ

When the temperature exceed the limit range value,
the driver can handle the interrupt.

Signed-off-by: Wei Ni <wni@nvidia.com>
Signed-off-by: Jean Delvare <khali@linux-fr.org>

1 files changed, 24 insertions, 0 deletions

diff --git a/drivers/hwmon/lm90.c b/drivers/hwmon/lm90.c
index 5e414ca80a78..499f473e0780 100644
--- a/drivers/hwmon/lm90.c
+++ b/drivers/hwmon/lm90.c
@@ -89,6 +89,7 @@
 #include <linux/err.h>
 #include <linux/mutex.h>
 #include <linux/sysfs.h>
+#include <linux/interrupt.h>
 
 /*
  * Addresses to scan
@@ -1445,6 +1446,17 @@ static bool lm90_is_tripped(struct i2c_client *client, u16 *status)
         return true;
 }
 
+static irqreturn_t lm90_irq_thread(int irq, void *dev_id)
+{
+        struct i2c_client *client = dev_id;
+        u16 status;
+
+        if (lm90_is_tripped(client, &status))
+                return IRQ_HANDLED;
+        else
+                return IRQ_NONE;
+}
+
 static int lm90_probe(struct i2c_client *client,
                       const struct i2c_device_id *id)
 {
@@ -1521,6 +1533,18 @@ static int lm90_probe(struct i2c_client *client,
                 goto exit_remove_files;
         }
 
+        if (client->irq) {
+                dev_dbg(dev, "IRQ: %d\n", client->irq);
+                err = devm_request_threaded_irq(dev, client->irq,
+                                                NULL, lm90_irq_thread,
+                                                IRQF_TRIGGER_LOW | IRQF_ONESHOT,
+                                                "lm90", client);
+                if (err < 0) {
+                        dev_err(dev, "cannot request IRQ %d\n", client->irq);
+                        goto exit_remove_files;
+                }
+        }
+
         return 0;
 
 exit_remove_files: