diff mbox series

[v2,01/12] fbdev: gxfb: use generic power management

Message ID 20200810185723.15540-2-vaibhavgupta40@gmail.com (mailing list archive)
State New, archived
Headers show
Series [v2,01/12] fbdev: gxfb: use generic power management | expand

Commit Message

Vaibhav Gupta Aug. 10, 2020, 6:57 p.m. UTC
Drivers should do only device-specific jobs. But in general, drivers using
legacy PCI PM framework for .suspend()/.resume() have to manage many PCI
PM-related tasks themselves which can be done by PCI Core itself. This
brings extra load on the driver and it directly calls PCI helper functions
to handle them.

Although the gxfb driver does not have that extra load, we should switch to
the new generic framework by updating function signatures and define a
"struct dev_pm_ops" variable to bind PM callbacks so that we can remove
the legacy .suspend & .resume bindings. Additionally, this helps us to
remove the unnecessary call to gxfb_suspend() in the event of Freeze and
Hibernate, as the function does nothing in their case.

Signed-off-by: Vaibhav Gupta <vaibhavgupta40@gmail.com>
---
 drivers/video/fbdev/geode/gxfb.h       |  5 ----
 drivers/video/fbdev/geode/gxfb_core.c  | 36 ++++++++++++++------------
 drivers/video/fbdev/geode/suspend_gx.c |  4 ---
 3 files changed, 20 insertions(+), 25 deletions(-)

Comments

Sam Ravnborg Aug. 16, 2020, 8:16 p.m. UTC | #1
Hi Vaibhav

On Tue, Aug 11, 2020 at 12:27:12AM +0530, Vaibhav Gupta wrote:
> Drivers should do only device-specific jobs. But in general, drivers using
> legacy PCI PM framework for .suspend()/.resume() have to manage many PCI
> PM-related tasks themselves which can be done by PCI Core itself. This
> brings extra load on the driver and it directly calls PCI helper functions
> to handle them.
> 
> Although the gxfb driver does not have that extra load,
Sorry, but I am lost here.
If this drivers does not have the extra load that you describe here then
I really cannot see why it is relevant for this driver to describe it.

This is a seldomly touched driver - so it helps if the changelog when we
finally touch the code is easy to parse.

> we should switch to
> the new generic framework by updating function signatures and define a
> "struct dev_pm_ops" variable to bind PM callbacks so that we can remove
> the legacy .suspend & .resume bindings.
This part matches the patch - good.

> Additionally, this helps us to
> remove the unnecessary call to gxfb_suspend() in the event of Freeze and
> Hibernate, as the function does nothing in their case.
What I think you are explaining above is that the pci pm support
will only call the suspend operation in case of suspend, so the 
state.event == PM_EVENT_SUSPEND can be dropped in gxfb_suspend().

For reference later I would prefer that this is explained a bit
more explicit - not that the changelog needs update anyway.
> 
> Signed-off-by: Vaibhav Gupta <vaibhavgupta40@gmail.com>
Patch looks good, but please give the changelog one more go.
I have not checked other patches - but I assume they would benefit
from a similar clarification.

	Sam

> ---
>  drivers/video/fbdev/geode/gxfb.h       |  5 ----
>  drivers/video/fbdev/geode/gxfb_core.c  | 36 ++++++++++++++------------
>  drivers/video/fbdev/geode/suspend_gx.c |  4 ---
>  3 files changed, 20 insertions(+), 25 deletions(-)
> 
> diff --git a/drivers/video/fbdev/geode/gxfb.h b/drivers/video/fbdev/geode/gxfb.h
> index d2e9c5c8e294..792c111c21e4 100644
> --- a/drivers/video/fbdev/geode/gxfb.h
> +++ b/drivers/video/fbdev/geode/gxfb.h
> @@ -21,7 +21,6 @@ struct gxfb_par {
>  	void __iomem *dc_regs;
>  	void __iomem *vid_regs;
>  	void __iomem *gp_regs;
> -#ifdef CONFIG_PM
>  	int powered_down;
>  
>  	/* register state, for power management functionality */
> @@ -36,7 +35,6 @@ struct gxfb_par {
>  	uint64_t fp[FP_REG_COUNT];
>  
>  	uint32_t pal[DC_PAL_COUNT];
> -#endif
>  };
>  
>  unsigned int gx_frame_buffer_size(void);
> @@ -49,11 +47,8 @@ void gx_set_dclk_frequency(struct fb_info *info);
>  void gx_configure_display(struct fb_info *info);
>  int gx_blank_display(struct fb_info *info, int blank_mode);
>  
> -#ifdef CONFIG_PM
>  int gx_powerdown(struct fb_info *info);
>  int gx_powerup(struct fb_info *info);
> -#endif
> -
>  
>  /* Graphics Processor registers (table 6-23 from the data book) */
>  enum gp_registers {
> diff --git a/drivers/video/fbdev/geode/gxfb_core.c b/drivers/video/fbdev/geode/gxfb_core.c
> index d38a148d4746..44089b331f91 100644
> --- a/drivers/video/fbdev/geode/gxfb_core.c
> +++ b/drivers/video/fbdev/geode/gxfb_core.c
> @@ -322,17 +322,14 @@ static struct fb_info *gxfb_init_fbinfo(struct device *dev)
>  	return info;
>  }
>  
> -#ifdef CONFIG_PM
> -static int gxfb_suspend(struct pci_dev *pdev, pm_message_t state)
> +static int __maybe_unused gxfb_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();
> -		gx_powerdown(info);
> -		fb_set_suspend(info, 1);
> -		console_unlock();
> -	}
> +	console_lock();
> +	gx_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 */
> @@ -340,9 +337,9 @@ static int gxfb_suspend(struct pci_dev *pdev, pm_message_t state)
>  	return 0;
>  }
>  
> -static int gxfb_resume(struct pci_dev *pdev)
> +static int __maybe_unused gxfb_resume(struct device *dev)
>  {
> -	struct fb_info *info = pci_get_drvdata(pdev);
> +	struct fb_info *info = dev_get_drvdata(dev);
>  	int ret;
>  
>  	console_lock();
> @@ -356,7 +353,6 @@ static int gxfb_resume(struct pci_dev *pdev)
>  	console_unlock();
>  	return 0;
>  }
> -#endif
>  
>  static int gxfb_probe(struct pci_dev *pdev, const struct pci_device_id *id)
>  {
> @@ -467,15 +463,23 @@ static const struct pci_device_id gxfb_id_table[] = {
>  
>  MODULE_DEVICE_TABLE(pci, gxfb_id_table);
>  
> +static const struct dev_pm_ops gxfb_pm_ops = {
> +#ifdef CONFIG_PM_SLEEP
> +	.suspend	= gxfb_suspend,
> +	.resume		= gxfb_resume,
> +	.freeze		= NULL,
> +	.thaw		= gxfb_resume,
> +	.poweroff	= NULL,
> +	.restore	= gxfb_resume,
> +#endif
> +};
> +
>  static struct pci_driver gxfb_driver = {
>  	.name		= "gxfb",
>  	.id_table	= gxfb_id_table,
>  	.probe		= gxfb_probe,
>  	.remove		= gxfb_remove,
> -#ifdef CONFIG_PM
> -	.suspend	= gxfb_suspend,
> -	.resume		= gxfb_resume,
> -#endif
> +	.driver.pm	= &gxfb_pm_ops,
>  };
>  
>  #ifndef MODULE
> diff --git a/drivers/video/fbdev/geode/suspend_gx.c b/drivers/video/fbdev/geode/suspend_gx.c
> index 1110a527c35c..8c49d4e98772 100644
> --- a/drivers/video/fbdev/geode/suspend_gx.c
> +++ b/drivers/video/fbdev/geode/suspend_gx.c
> @@ -11,8 +11,6 @@
>  
>  #include "gxfb.h"
>  
> -#ifdef CONFIG_PM
> -
>  static void gx_save_regs(struct gxfb_par *par)
>  {
>  	int i;
> @@ -259,5 +257,3 @@ int gx_powerup(struct fb_info *info)
>  	par->powered_down  = 0;
>  	return 0;
>  }
> -
> -#endif
> -- 
> 2.27.0
Vaibhav Gupta Aug. 17, 2020, 7:45 a.m. UTC | #2
On Sun, Aug 16, 2020 at 10:16:01PM +0200, Sam Ravnborg wrote:
> Hi Vaibhav
> 
> On Tue, Aug 11, 2020 at 12:27:12AM +0530, Vaibhav Gupta wrote:
> > Drivers should do only device-specific jobs. But in general, drivers using
> > legacy PCI PM framework for .suspend()/.resume() have to manage many PCI
> > PM-related tasks themselves which can be done by PCI Core itself. This
> > brings extra load on the driver and it directly calls PCI helper functions
> > to handle them.
> > 
> > Although the gxfb driver does not have that extra load,
> Sorry, but I am lost here.
> If this drivers does not have the extra load that you describe here then
> I really cannot see why it is relevant for this driver to describe it.
> 
> This is a seldomly touched driver - so it helps if the changelog when we
> finally touch the code is easy to parse.
> 
> > we should switch to
> > the new generic framework by updating function signatures and define a
> > "struct dev_pm_ops" variable to bind PM callbacks so that we can remove
> > the legacy .suspend & .resume bindings.
> This part matches the patch - good.
> 
> > Additionally, this helps us to
> > remove the unnecessary call to gxfb_suspend() in the event of Freeze and
> > Hibernate, as the function does nothing in their case.
> What I think you are explaining above is that the pci pm support
> will only call the suspend operation in case of suspend, so the 
> state.event == PM_EVENT_SUSPEND can be dropped in gxfb_suspend().
> 
> For reference later I would prefer that this is explained a bit
> more explicit - not that the changelog needs update anyway.
> > 
> > Signed-off-by: Vaibhav Gupta <vaibhavgupta40@gmail.com>
> Patch looks good, but please give the changelog one more go.
> I have not checked other patches - but I assume they would benefit
> from a similar clarification.
> 
> 	Sam
> 
Hello Sam

I will do the changes as suggested.

Thanks
Vaibhav Gupta
> > ---
> >  drivers/video/fbdev/geode/gxfb.h       |  5 ----
> >  drivers/video/fbdev/geode/gxfb_core.c  | 36 ++++++++++++++------------
> >  drivers/video/fbdev/geode/suspend_gx.c |  4 ---
> >  3 files changed, 20 insertions(+), 25 deletions(-)
> > 
> > diff --git a/drivers/video/fbdev/geode/gxfb.h b/drivers/video/fbdev/geode/gxfb.h
> > index d2e9c5c8e294..792c111c21e4 100644
> > --- a/drivers/video/fbdev/geode/gxfb.h
> > +++ b/drivers/video/fbdev/geode/gxfb.h
> > @@ -21,7 +21,6 @@ struct gxfb_par {
> >  	void __iomem *dc_regs;
> >  	void __iomem *vid_regs;
> >  	void __iomem *gp_regs;
> > -#ifdef CONFIG_PM
> >  	int powered_down;
> >  
> >  	/* register state, for power management functionality */
> > @@ -36,7 +35,6 @@ struct gxfb_par {
> >  	uint64_t fp[FP_REG_COUNT];
> >  
> >  	uint32_t pal[DC_PAL_COUNT];
> > -#endif
> >  };
> >  
> >  unsigned int gx_frame_buffer_size(void);
> > @@ -49,11 +47,8 @@ void gx_set_dclk_frequency(struct fb_info *info);
> >  void gx_configure_display(struct fb_info *info);
> >  int gx_blank_display(struct fb_info *info, int blank_mode);
> >  
> > -#ifdef CONFIG_PM
> >  int gx_powerdown(struct fb_info *info);
> >  int gx_powerup(struct fb_info *info);
> > -#endif
> > -
> >  
> >  /* Graphics Processor registers (table 6-23 from the data book) */
> >  enum gp_registers {
> > diff --git a/drivers/video/fbdev/geode/gxfb_core.c b/drivers/video/fbdev/geode/gxfb_core.c
> > index d38a148d4746..44089b331f91 100644
> > --- a/drivers/video/fbdev/geode/gxfb_core.c
> > +++ b/drivers/video/fbdev/geode/gxfb_core.c
> > @@ -322,17 +322,14 @@ static struct fb_info *gxfb_init_fbinfo(struct device *dev)
> >  	return info;
> >  }
> >  
> > -#ifdef CONFIG_PM
> > -static int gxfb_suspend(struct pci_dev *pdev, pm_message_t state)
> > +static int __maybe_unused gxfb_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();
> > -		gx_powerdown(info);
> > -		fb_set_suspend(info, 1);
> > -		console_unlock();
> > -	}
> > +	console_lock();
> > +	gx_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 */
> > @@ -340,9 +337,9 @@ static int gxfb_suspend(struct pci_dev *pdev, pm_message_t state)
> >  	return 0;
> >  }
> >  
> > -static int gxfb_resume(struct pci_dev *pdev)
> > +static int __maybe_unused gxfb_resume(struct device *dev)
> >  {
> > -	struct fb_info *info = pci_get_drvdata(pdev);
> > +	struct fb_info *info = dev_get_drvdata(dev);
> >  	int ret;
> >  
> >  	console_lock();
> > @@ -356,7 +353,6 @@ static int gxfb_resume(struct pci_dev *pdev)
> >  	console_unlock();
> >  	return 0;
> >  }
> > -#endif
> >  
> >  static int gxfb_probe(struct pci_dev *pdev, const struct pci_device_id *id)
> >  {
> > @@ -467,15 +463,23 @@ static const struct pci_device_id gxfb_id_table[] = {
> >  
> >  MODULE_DEVICE_TABLE(pci, gxfb_id_table);
> >  
> > +static const struct dev_pm_ops gxfb_pm_ops = {
> > +#ifdef CONFIG_PM_SLEEP
> > +	.suspend	= gxfb_suspend,
> > +	.resume		= gxfb_resume,
> > +	.freeze		= NULL,
> > +	.thaw		= gxfb_resume,
> > +	.poweroff	= NULL,
> > +	.restore	= gxfb_resume,
> > +#endif
> > +};
> > +
> >  static struct pci_driver gxfb_driver = {
> >  	.name		= "gxfb",
> >  	.id_table	= gxfb_id_table,
> >  	.probe		= gxfb_probe,
> >  	.remove		= gxfb_remove,
> > -#ifdef CONFIG_PM
> > -	.suspend	= gxfb_suspend,
> > -	.resume		= gxfb_resume,
> > -#endif
> > +	.driver.pm	= &gxfb_pm_ops,
> >  };
> >  
> >  #ifndef MODULE
> > diff --git a/drivers/video/fbdev/geode/suspend_gx.c b/drivers/video/fbdev/geode/suspend_gx.c
> > index 1110a527c35c..8c49d4e98772 100644
> > --- a/drivers/video/fbdev/geode/suspend_gx.c
> > +++ b/drivers/video/fbdev/geode/suspend_gx.c
> > @@ -11,8 +11,6 @@
> >  
> >  #include "gxfb.h"
> >  
> > -#ifdef CONFIG_PM
> > -
> >  static void gx_save_regs(struct gxfb_par *par)
> >  {
> >  	int i;
> > @@ -259,5 +257,3 @@ int gx_powerup(struct fb_info *info)
> >  	par->powered_down  = 0;
> >  	return 0;
> >  }
> > -
> > -#endif
> > -- 
> > 2.27.0
diff mbox series

Patch

diff --git a/drivers/video/fbdev/geode/gxfb.h b/drivers/video/fbdev/geode/gxfb.h
index d2e9c5c8e294..792c111c21e4 100644
--- a/drivers/video/fbdev/geode/gxfb.h
+++ b/drivers/video/fbdev/geode/gxfb.h
@@ -21,7 +21,6 @@  struct gxfb_par {
 	void __iomem *dc_regs;
 	void __iomem *vid_regs;
 	void __iomem *gp_regs;
-#ifdef CONFIG_PM
 	int powered_down;
 
 	/* register state, for power management functionality */
@@ -36,7 +35,6 @@  struct gxfb_par {
 	uint64_t fp[FP_REG_COUNT];
 
 	uint32_t pal[DC_PAL_COUNT];
-#endif
 };
 
 unsigned int gx_frame_buffer_size(void);
@@ -49,11 +47,8 @@  void gx_set_dclk_frequency(struct fb_info *info);
 void gx_configure_display(struct fb_info *info);
 int gx_blank_display(struct fb_info *info, int blank_mode);
 
-#ifdef CONFIG_PM
 int gx_powerdown(struct fb_info *info);
 int gx_powerup(struct fb_info *info);
-#endif
-
 
 /* Graphics Processor registers (table 6-23 from the data book) */
 enum gp_registers {
diff --git a/drivers/video/fbdev/geode/gxfb_core.c b/drivers/video/fbdev/geode/gxfb_core.c
index d38a148d4746..44089b331f91 100644
--- a/drivers/video/fbdev/geode/gxfb_core.c
+++ b/drivers/video/fbdev/geode/gxfb_core.c
@@ -322,17 +322,14 @@  static struct fb_info *gxfb_init_fbinfo(struct device *dev)
 	return info;
 }
 
-#ifdef CONFIG_PM
-static int gxfb_suspend(struct pci_dev *pdev, pm_message_t state)
+static int __maybe_unused gxfb_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();
-		gx_powerdown(info);
-		fb_set_suspend(info, 1);
-		console_unlock();
-	}
+	console_lock();
+	gx_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 */
@@ -340,9 +337,9 @@  static int gxfb_suspend(struct pci_dev *pdev, pm_message_t state)
 	return 0;
 }
 
-static int gxfb_resume(struct pci_dev *pdev)
+static int __maybe_unused gxfb_resume(struct device *dev)
 {
-	struct fb_info *info = pci_get_drvdata(pdev);
+	struct fb_info *info = dev_get_drvdata(dev);
 	int ret;
 
 	console_lock();
@@ -356,7 +353,6 @@  static int gxfb_resume(struct pci_dev *pdev)
 	console_unlock();
 	return 0;
 }
-#endif
 
 static int gxfb_probe(struct pci_dev *pdev, const struct pci_device_id *id)
 {
@@ -467,15 +463,23 @@  static const struct pci_device_id gxfb_id_table[] = {
 
 MODULE_DEVICE_TABLE(pci, gxfb_id_table);
 
+static const struct dev_pm_ops gxfb_pm_ops = {
+#ifdef CONFIG_PM_SLEEP
+	.suspend	= gxfb_suspend,
+	.resume		= gxfb_resume,
+	.freeze		= NULL,
+	.thaw		= gxfb_resume,
+	.poweroff	= NULL,
+	.restore	= gxfb_resume,
+#endif
+};
+
 static struct pci_driver gxfb_driver = {
 	.name		= "gxfb",
 	.id_table	= gxfb_id_table,
 	.probe		= gxfb_probe,
 	.remove		= gxfb_remove,
-#ifdef CONFIG_PM
-	.suspend	= gxfb_suspend,
-	.resume		= gxfb_resume,
-#endif
+	.driver.pm	= &gxfb_pm_ops,
 };
 
 #ifndef MODULE
diff --git a/drivers/video/fbdev/geode/suspend_gx.c b/drivers/video/fbdev/geode/suspend_gx.c
index 1110a527c35c..8c49d4e98772 100644
--- a/drivers/video/fbdev/geode/suspend_gx.c
+++ b/drivers/video/fbdev/geode/suspend_gx.c
@@ -11,8 +11,6 @@ 
 
 #include "gxfb.h"
 
-#ifdef CONFIG_PM
-
 static void gx_save_regs(struct gxfb_par *par)
 {
 	int i;
@@ -259,5 +257,3 @@  int gx_powerup(struct fb_info *info)
 	par->powered_down  = 0;
 	return 0;
 }
-
-#endif