[Linux-kernel-mentees] [PATCH v1 02/12] fbdev: lxfb: use generic power management

Vaibhav Gupta vaibhavgupta40 at gmail.com
Wed Aug 5 18:07:12 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/geode/lxfb.h      |  5 ----
 drivers/video/fbdev/geode/lxfb_core.c | 37 +++++++++++++++------------
 drivers/video/fbdev/geode/lxfb_ops.c  |  4 ---
 3 files changed, 20 insertions(+), 26 deletions(-)

diff --git a/drivers/video/fbdev/geode/lxfb.h b/drivers/video/fbdev/geode/lxfb.h
index ef24bf6d49dc..d37b32dbcd68 100644
--- a/drivers/video/fbdev/geode/lxfb.h
+++ b/drivers/video/fbdev/geode/lxfb.h
@@ -29,7 +29,6 @@ struct lxfb_par {
 	void __iomem *gp_regs;
 	void __iomem *dc_regs;
 	void __iomem *vp_regs;
-#ifdef CONFIG_PM
 	int powered_down;
 
 	/* register state, for power mgmt functionality */
@@ -50,7 +49,6 @@ struct lxfb_par {
 	uint32_t hcoeff[DC_HFILT_COUNT * 2];
 	uint32_t vcoeff[DC_VFILT_COUNT];
 	uint32_t vp_coeff[VP_COEFF_SIZE / 4];
-#endif
 };
 
 static inline unsigned int lx_get_pitch(unsigned int xres, int bpp)
@@ -64,11 +62,8 @@ int lx_blank_display(struct fb_info *, int);
 void lx_set_palette_reg(struct fb_info *, unsigned int, unsigned int,
 			unsigned int, unsigned int);
 
-#ifdef CONFIG_PM
 int lx_powerdown(struct fb_info *info);
 int lx_powerup(struct fb_info *info);
-#endif
-
 
 /* Graphics Processor registers (table 6-29 from the data book) */
 enum gp_registers {
diff --git a/drivers/video/fbdev/geode/lxfb_core.c b/drivers/video/fbdev/geode/lxfb_core.c
index adc2d9c2395e..66c81262d18f 100644
--- a/drivers/video/fbdev/geode/lxfb_core.c
+++ b/drivers/video/fbdev/geode/lxfb_core.c
@@ -443,17 +443,14 @@ static struct fb_info *lxfb_init_fbinfo(struct device *dev)
 	return info;
 }
 
-#ifdef CONFIG_PM
-static int lxfb_suspend(struct pci_dev *pdev, pm_message_t state)
+static int __maybe_unused lxfb_suspend(struct device *dev)
 {
-	struct fb_info *info = pci_get_drvdata(pdev);
+	struct fb_info *info = dev_get_drvdata(dev);
 
-	if (state.event == PM_EVENT_SUSPEND) {
-		console_lock();
-		lx_powerdown(info);
-		fb_set_suspend(info, 1);
-		console_unlock();
-	}
+	console_lock();
+	lx_powerdown(info);
+	fb_set_suspend(info, 1);
+	console_unlock();
 
 	/* there's no point in setting PCI states; we emulate PCI, so
 	 * we don't end up getting power savings anyways */
@@ -461,9 +458,9 @@ static int lxfb_suspend(struct pci_dev *pdev, pm_message_t state)
 	return 0;
 }
 
-static int lxfb_resume(struct pci_dev *pdev)
+static int __maybe_unused lxfb_resume(struct device *dev)
 {
-	struct fb_info *info = pci_get_drvdata(pdev);
+	struct fb_info *info = dev_get_drvdata(dev);
 	int ret;
 
 	console_lock();
@@ -477,10 +474,6 @@ static int lxfb_resume(struct pci_dev *pdev)
 	console_unlock();
 	return 0;
 }
-#else
-#define lxfb_suspend NULL
-#define lxfb_resume NULL
-#endif
 
 static int lxfb_probe(struct pci_dev *pdev, const struct pci_device_id *id)
 {
@@ -600,13 +593,23 @@ static struct pci_device_id lxfb_id_table[] = {
 
 MODULE_DEVICE_TABLE(pci, lxfb_id_table);
 
+static const struct dev_pm_ops lxfb_pm_ops = {
+#ifdef CONFIG_PM_SLEEP
+	.suspend	= lxfb_suspend,
+	.resume		= lxfb_resume,
+	.freeze		= NULL,
+	.thaw		= lxfb_resume,
+	.poweroff	= NULL,
+	.restore	= lxfb_resume,
+#endif
+};
+
 static struct pci_driver lxfb_driver = {
 	.name		= "lxfb",
 	.id_table	= lxfb_id_table,
 	.probe		= lxfb_probe,
 	.remove		= lxfb_remove,
-	.suspend	= lxfb_suspend,
-	.resume		= lxfb_resume,
+	.driver.pm	= &lxfb_pm_ops,
 };
 
 #ifndef MODULE
diff --git a/drivers/video/fbdev/geode/lxfb_ops.c b/drivers/video/fbdev/geode/lxfb_ops.c
index 5be8bc62844c..b3a041fce570 100644
--- a/drivers/video/fbdev/geode/lxfb_ops.c
+++ b/drivers/video/fbdev/geode/lxfb_ops.c
@@ -580,8 +580,6 @@ int lx_blank_display(struct fb_info *info, int blank_mode)
 	return 0;
 }
 
-#ifdef CONFIG_PM
-
 static void lx_save_regs(struct lxfb_par *par)
 {
 	uint32_t filt;
@@ -837,5 +835,3 @@ int lx_powerup(struct fb_info *info)
 	par->powered_down = 0;
 	return 0;
 }
-
-#endif
-- 
2.27.0



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