HID: amd_sfh: Improve boot time when SFH is available

AMD SFH load takes longer time in initialization. Hence split and defer
initialization code to improve SFH module load time and boot time of the
system when SFH is available.
Signed-off-by: Basavaraj Natikar <Basavaraj.Natikar@amd.com>
Signed-off-by: Jiri Kosina <jkosina@suse.com>

drivers/hid/amd-sfh-hid/amd_sfh_common.h

@@ -53,6 +53,8 @@ struct amd_mp2_dev {
 	/* mp2 active control status */
 	u32 mp2_acs;
 	struct sfh_dev_status dev_en;
+	struct work_struct work;
+	u8 init_done;
 };
 
 struct amd_mp2_ops {

drivers/hid/amd-sfh-hid/amd_sfh_pcie.c

@@ -10,6 +10,7 @@
 
 #include <linux/bitops.h>
 #include <linux/delay.h>
+#include <linux/devm-helpers.h>
 #include <linux/dma-mapping.h>
 #include <linux/dmi.h>
 #include <linux/interrupt.h>
@@ -329,6 +330,48 @@ static const struct dmi_system_id dmi_nodevs[] = {
 	{ }
 };
 
+static void sfh1_1_init_work(struct work_struct *work)
+{
+	struct amd_mp2_dev *mp2 = container_of(work, struct amd_mp2_dev, work);
+	struct pci_dev *pdev = mp2->pdev;
+	int rc;
+
+	rc = mp2->sfh1_1_ops->init(mp2);
+	if (rc) {
+		dev_err(&pdev->dev, "sfh1_1_init failed err %d\n", rc);
+		return;
+	}
+
+	amd_sfh_clear_intr(mp2);
+	mp2->init_done = 1;
+}
+
+static void sfh_init_work(struct work_struct *work)
+{
+	struct amd_mp2_dev *mp2 = container_of(work, struct amd_mp2_dev, work);
+	struct pci_dev *pdev = mp2->pdev;
+	int rc;
+
+	rc = amd_sfh_hid_client_init(mp2);
+	if (rc) {
+		amd_sfh_clear_intr(mp2);
+		dev_err(&pdev->dev, "amd_sfh_hid_client_init failed err %d\n", rc);
+		return;
+	}
+
+	amd_sfh_clear_intr(mp2);
+	mp2->init_done = 1;
+}
+
+static void amd_sfh_remove(struct pci_dev *pdev)
+{
+	struct amd_mp2_dev *mp2 = pci_get_drvdata(pdev);
+
+	flush_work(&mp2->work);
+	if (mp2->init_done)
+		mp2->mp2_ops->remove(mp2);
+}
+
 static int amd_mp2_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
 {
 	struct amd_mp2_dev *privdata;
@@ -367,10 +410,12 @@ static int amd_mp2_pci_probe(struct pci_dev *pdev, const struct pci_device_id *i
 
 	privdata->sfh1_1_ops = (const struct amd_sfh1_1_ops *)id->driver_data;
 	if (privdata->sfh1_1_ops) {
-		rc = privdata->sfh1_1_ops->init(privdata);
+		rc = devm_work_autocancel(&pdev->dev, &privdata->work, sfh1_1_init_work);
 		if (rc)
 			return rc;
-		goto init_done;
+
+		schedule_work(&privdata->work);
+		return 0;
 	}
 
 	mp2_select_ops(privdata);
@@ -381,33 +426,34 @@ static int amd_mp2_pci_probe(struct pci_dev *pdev, const struct pci_device_id *i
 		return rc;
 	}
 
-	rc = amd_sfh_hid_client_init(privdata);
+	rc = devm_work_autocancel(&pdev->dev, &privdata->work, sfh_init_work);
 	if (rc) {
 		amd_sfh_clear_intr(privdata);
-		if (rc != -EOPNOTSUPP)
-			dev_err(&pdev->dev, "amd_sfh_hid_client_init failed\n");
 		return rc;
 	}
 
-init_done:
-	amd_sfh_clear_intr(privdata);
-
-	return devm_add_action_or_reset(&pdev->dev, privdata->mp2_ops->remove, privdata);
+	schedule_work(&privdata->work);
+	return 0;
 }
 
 static void amd_sfh_shutdown(struct pci_dev *pdev)
 {
 	struct amd_mp2_dev *mp2 = pci_get_drvdata(pdev);
 
-	if (mp2 && mp2->mp2_ops)
-		mp2->mp2_ops->stop_all(mp2);
+	if (mp2) {
+		flush_work(&mp2->work);
+		if (mp2->init_done)
+			mp2->mp2_ops->stop_all(mp2);
+	}
 }
 
 static int __maybe_unused amd_mp2_pci_resume(struct device *dev)
 {
 	struct amd_mp2_dev *mp2 = dev_get_drvdata(dev);
 
-	mp2->mp2_ops->resume(mp2);
+	flush_work(&mp2->work);
+	if (mp2->init_done)
+		mp2->mp2_ops->resume(mp2);
 
 	return 0;
 }
@@ -416,7 +462,9 @@ static int __maybe_unused amd_mp2_pci_suspend(struct device *dev)
 {
 	struct amd_mp2_dev *mp2 = dev_get_drvdata(dev);
 
-	mp2->mp2_ops->suspend(mp2);
+	flush_work(&mp2->work);
+	if (mp2->init_done)
+		mp2->mp2_ops->suspend(mp2);
 
 	return 0;
 }
@@ -438,6 +486,7 @@ static struct pci_driver amd_mp2_pci_driver = {
 	.probe		= amd_mp2_pci_probe,
 	.driver.pm	= &amd_mp2_pm_ops,
 	.shutdown	= amd_sfh_shutdown,
+	.remove		= amd_sfh_remove,
 };
 module_pci_driver(amd_mp2_pci_driver);