[Linux-kernel-mentees] [PATCH v1 09/12] fbdev: i740fb: use generic power management

Vaibhav Gupta vaibhavgupta40 at gmail.com
Wed Aug 5 18:07:19 UTC 2020


Drivers using legacy power management .suspen()/.resume() callbacks
have to manage PCI states and device's PM states themselves. They also
need to take care of standard configuration registers.

Switch to generic power management framework using a single
"struct dev_pm_ops" variable to take the unnecessary load from the driver.
This also avoids the need for the driver to directly call most of the PCI
helper functions and device power state control functions, as through
the generic framework PCI Core takes care of the necessary operations,
and drivers are required to do only device-specific jobs.

Signed-off-by: Vaibhav Gupta <vaibhavgupta40 at gmail.com>
---
 drivers/video/fbdev/i740fb.c | 40 +++++++++++++++---------------------
 1 file changed, 16 insertions(+), 24 deletions(-)

diff --git a/drivers/video/fbdev/i740fb.c b/drivers/video/fbdev/i740fb.c
index c65ec7386e87..8d7f06fc8a5a 100644
--- a/drivers/video/fbdev/i740fb.c
+++ b/drivers/video/fbdev/i740fb.c
@@ -1175,16 +1175,11 @@ static void i740fb_remove(struct pci_dev *dev)
 	}
 }
 
-#ifdef CONFIG_PM
-static int i740fb_suspend(struct pci_dev *dev, pm_message_t state)
+static int __maybe_unused i740fb_suspend(struct device *dev)
 {
-	struct fb_info *info = pci_get_drvdata(dev);
+	struct fb_info *info = dev_get_drvdata(dev);
 	struct i740fb_par *par = info->par;
 
-	/* don't disable console during hibernation and wakeup from it */
-	if (state.event == PM_EVENT_FREEZE || state.event == PM_EVENT_PRETHAW)
-		return 0;
-
 	console_lock();
 	mutex_lock(&(par->open_lock));
 
@@ -1197,19 +1192,15 @@ static int i740fb_suspend(struct pci_dev *dev, pm_message_t state)
 
 	fb_set_suspend(info, 1);
 
-	pci_save_state(dev);
-	pci_disable_device(dev);
-	pci_set_power_state(dev, pci_choose_state(dev, state));
-
 	mutex_unlock(&(par->open_lock));
 	console_unlock();
 
 	return 0;
 }
 
-static int i740fb_resume(struct pci_dev *dev)
+static int __maybe_unused i740fb_resume(struct device *dev)
 {
-	struct fb_info *info = pci_get_drvdata(dev);
+	struct fb_info *info = dev_get_drvdata(dev);
 	struct i740fb_par *par = info->par;
 
 	console_lock();
@@ -1218,11 +1209,6 @@ static int i740fb_resume(struct pci_dev *dev)
 	if (par->ref_count == 0)
 		goto fail;
 
-	pci_set_power_state(dev, PCI_D0);
-	pci_restore_state(dev);
-	if (pci_enable_device(dev))
-		goto fail;
-
 	i740fb_set_par(info);
 	fb_set_suspend(info, 0);
 
@@ -1231,10 +1217,17 @@ static int i740fb_resume(struct pci_dev *dev)
 	console_unlock();
 	return 0;
 }
-#else
-#define i740fb_suspend NULL
-#define i740fb_resume NULL
-#endif /* CONFIG_PM */
+
+static const struct dev_pm_ops i740fb_pm_ops = {
+#ifdef CONFIG_PM_SLEEP
+	.suspend	= i740fb_suspend,
+	.resume		= i740fb_resume,
+	.freeze		= NULL,
+	.thaw		= i740fb_resume,
+	.poweroff	= i740fb_suspend,
+	.restore	= i740fb_resume,
+#endif /* CONFIG_PM_SLEEP */
+};
 
 #define I740_ID_PCI 0x00d1
 #define I740_ID_AGP 0x7800
@@ -1251,8 +1244,7 @@ static struct pci_driver i740fb_driver = {
 	.id_table	= i740fb_id_table,
 	.probe		= i740fb_probe,
 	.remove		= i740fb_remove,
-	.suspend	= i740fb_suspend,
-	.resume		= i740fb_resume,
+	.driver.pm	= &i740fb_pm_ops,
 };
 
 #ifndef MODULE
-- 
2.27.0



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