On Mon, Jul 27, 2020 at 02:26:21PM +0530, Vinod Koul wrote:

Hi Vaibhav,

On 20-07-20, 17:07, Vaibhav Gupta wrote:

quoted

Drivers using legacy PM have to manage PCI states and device's PM states
themselves. They also need to take care of configuration registers.

With improved and powerful support of generic PM, PCI Core takes care of
above mentioned, device-independent, jobs.

This driver makes use of PCI helper functions like
pci_save/restore_state(), pci_enable/disable_device(),
and pci_set_power_state() to do required operations. In generic mode, they
are no longer needed.

Change function parameter in both .suspend() and .resume() to
"struct device*" type. Use dev_get_drvdata() to get drv data.

You are doing too many things in One patch. Do consider splitting them
up to a change per patch. for example using __maybe could be one patch,
removing code is suspend-resume callbacks would be other one.

Sure. But I guess just marking of "__maybe_unused" is not some significant
change. All the legacy PCI drivers have .suspend() and .resume() inside
"#ifdef CONFIG_PM" container.
It is only when I am upgrading them one by one to generic, I remove the
container and mark them with the attribute. So it is like a part of complete
generic upgrade.

Thanks
Vaibhav Gupta

quoted

Compile-tested only.

I would like to see some testing before we merge this

quoted

Signed-off-by: Vaibhav Gupta <vaibhavgupta40@gmail.com>
---
 drivers/dma/pch_dma.c | 35 +++++++++--------------------------
 1 file changed, 9 insertions(+), 26 deletions(-)

diff --git a/drivers/dma/pch_dma.c b/drivers/dma/pch_dma.c
index a3b0b4c56a19..e93005837e3f 100644
--- a/drivers/dma/pch_dma.c
+++ b/drivers/dma/pch_dma.c

@@ -735,8 +735,7 @@ static irqreturn_t pd_irq(int irq, void *devid)
 	return ret0 | ret2;
 }
 
-#ifdef	CONFIG_PM
-static void pch_dma_save_regs(struct pch_dma *pd)
+static void __maybe_unused pch_dma_save_regs(struct pch_dma *pd)
 {
 	struct pch_dma_chan *pd_chan;
 	struct dma_chan *chan, *_c;

@@ -759,7 +758,7 @@ static void pch_dma_save_regs(struct pch_dma *pd)
 	}
 }
 
-static void pch_dma_restore_regs(struct pch_dma *pd)
+static void __maybe_unused pch_dma_restore_regs(struct pch_dma *pd)
 {
 	struct pch_dma_chan *pd_chan;
 	struct dma_chan *chan, *_c;

@@ -782,40 +781,25 @@ static void pch_dma_restore_regs(struct pch_dma *pd)
 	}
 }
 
-static int pch_dma_suspend(struct pci_dev *pdev, pm_message_t state)
+static int __maybe_unused pch_dma_suspend(struct device *dev)
 {
-	struct pch_dma *pd = pci_get_drvdata(pdev);
+	struct pch_dma *pd = dev_get_drvdata(dev);
 
 	if (pd)
 		pch_dma_save_regs(pd);
 
-	pci_save_state(pdev);
-	pci_disable_device(pdev);
-	pci_set_power_state(pdev, pci_choose_state(pdev, state));
-
 	return 0;
 }
 
-static int pch_dma_resume(struct pci_dev *pdev)
+static int __maybe_unused pch_dma_resume(struct device *dev)
 {
-	struct pch_dma *pd = pci_get_drvdata(pdev);
-	int err;
-
-	pci_set_power_state(pdev, PCI_D0);
-	pci_restore_state(pdev);
-
-	err = pci_enable_device(pdev);
-	if (err) {
-		dev_dbg(&pdev->dev, "failed to enable device\n");
-		return err;
-	}
+	struct pch_dma *pd = dev_get_drvdata(dev);
 
 	if (pd)
 		pch_dma_restore_regs(pd);
 
 	return 0;
 }
-#endif
 
 static int pch_dma_probe(struct pci_dev *pdev,
 				   const struct pci_device_id *id)

@@ -993,15 +977,14 @@ static const struct pci_device_id pch_dma_id_table[] = {
 	{ 0, },
 };
 
+static SIMPLE_DEV_PM_OPS(pch_dma_pm_ops, pch_dma_suspend, pch_dma_resume);
+
 static struct pci_driver pch_dma_driver = {
 	.name		= DRV_NAME,
 	.id_table	= pch_dma_id_table,
 	.probe		= pch_dma_probe,
 	.remove		= pch_dma_remove,
-#ifdef CONFIG_PM
-	.suspend	= pch_dma_suspend,
-	.resume		= pch_dma_resume,
-#endif
+	.driver.pm	= &pch_dma_pm_ops,
 };
 
 module_pci_driver(pch_dma_driver);

-- 
2.27.0

-- 
~Vinod

_______________________________________________
Linux-kernel-mentees mailing list
Linux-kernel-mentees@lists.linuxfoundation.org
https://lists.linuxfoundation.org/mailman/listinfo/linux-kernel-mentees