[PATCH v2 0/4] Introduce pcim_alloc_irq_vectors()

[PATCH v2 0/4] Introduce pcim_alloc_irq_vectors()

[Dejin Zheng]

Introduce pcim_alloc_irq_vectors(), a device-managed version of
pci_alloc_irq_vectors(), In some i2c drivers, If pcim_enable_device()
has been called before, then pci_alloc_irq_vectors() is actually a
device-managed function. It is used as a device-managed function, So
replace it with pcim_alloc_irq_vectors().

Changelog
---------
v1 -> v2:
	- Use pci_free_irq_vectors() to replace some code in
	  pcim_release().
	- Modify some commit messages.

Andy and Krzysztof, thanks for your help!

Dejin Zheng (4):
  PCI: Introduce pcim_alloc_irq_vectors()
  Documentation: devres: Add pcim_alloc_irq_vectors()
  i2c: designware: Use the correct name of device-managed function
  i2c: thunderx: Use the correct name of device-managed function

 .../driver-api/driver-model/devres.rst        |  1 +
 drivers/i2c/busses/i2c-designware-pcidrv.c    |  2 +-
 drivers/i2c/busses/i2c-thunderx-pcidrv.c      |  2 +-
 drivers/pci/pci.c                             | 33 ++++++++++++++++---
 include/linux/pci.h                           |  3 ++
 5 files changed, 35 insertions(+), 6 deletions(-)

-- 
2.25.0

[PATCH v2 1/4] PCI: Introduce pcim_alloc_irq_vectors()

[Dejin Zheng]

Introduce pcim_alloc_irq_vectors(), a device-managed version of
pci_alloc_irq_vectors(). Introducing this function can simplify
the error handling path in many drivers.

Suggested-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Dejin Zheng <zhengdejin5@gmail.com>
---
v1 -> v2:
	- Use pci_free_irq_vectors() to replace some code in
	  pcim_release().
	- Modify some commit messages.

 drivers/pci/pci.c   | 33 +++++++++++++++++++++++++++++----
 include/linux/pci.h |  3 +++
 2 files changed, 32 insertions(+), 4 deletions(-)

diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index b67c4327d307..db799d089c85 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -1969,10 +1969,7 @@ static void pcim_release(struct device *gendev, void *res)
 	struct pci_devres *this = res;
 	int i;
 
-	if (dev->msi_enabled)
-		pci_disable_msi(dev);
-	if (dev->msix_enabled)
-		pci_disable_msix(dev);
+	pci_free_irq_vectors(dev);
 
 	for (i = 0; i < DEVICE_COUNT_RESOURCE; i++)
 		if (this->region_mask & (1 << i))
@@ -2054,6 +2051,34 @@ void pcim_pin_device(struct pci_dev *pdev)
 }
 EXPORT_SYMBOL(pcim_pin_device);
 
+/**
+ * pcim_alloc_irq_vectors - a device-managed pci_alloc_irq_vectors()
+ * @dev:		PCI device to operate on
+ * @min_vecs:		minimum number of vectors required (must be >= 1)
+ * @max_vecs:		maximum (desired) number of vectors
+ * @flags:		flags or quirks for the allocation
+ *
+ * Return the number of vectors allocated, (which might be smaller than
+ * @max_vecs) if successful, or a negative error code on error. If less
+ * than @min_vecs interrupt vectors are available for @dev the function
+ * will fail with -ENOSPC.
+ *
+ * It depends on calling pcim_enable_device() to make IRQ resources
+ * manageable.
+ */
+int pcim_alloc_irq_vectors(struct pci_dev *dev, unsigned int min_vecs,
+				unsigned int max_vecs, unsigned int flags)
+{
+	struct pci_devres *dr;
+
+	dr = find_pci_dr(dev);
+	if (!dr || !dr->enabled)
+		return -EINVAL;
+
+	return pci_alloc_irq_vectors(dev, min_vecs, max_vecs, flags);
+}
+EXPORT_SYMBOL(pcim_alloc_irq_vectors);
+
 /*
  * pcibios_add_device - provide arch specific hooks when adding device dev
  * @dev: the PCI device being added
diff --git a/include/linux/pci.h b/include/linux/pci.h
index 86c799c97b77..d75ba85ddfc5 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -1818,6 +1818,9 @@ pci_alloc_irq_vectors(struct pci_dev *dev, unsigned int min_vecs,
 					      NULL);
 }
 
+int pcim_alloc_irq_vectors(struct pci_dev *dev, unsigned int min_vecs,
+				unsigned int max_vecs, unsigned int flags);
+
 /* Include architecture-dependent settings and functions */
 
 #include <asm/pci.h>
-- 
2.25.0

Re: [PATCH v2 1/4] PCI: Introduce pcim_alloc_irq_vectors()

[Andy Shevchenko]

On Tue, Feb 16, 2021 at 10:18:07PM +0800, Dejin Zheng wrote:
> Introduce pcim_alloc_irq_vectors(), a device-managed version of
> pci_alloc_irq_vectors(). Introducing this function can simplify
> the error handling path in many drivers.

> -	if (dev->msi_enabled)
> -		pci_disable_msi(dev);
> -	if (dev->msix_enabled)
> -		pci_disable_msix(dev);
> +	pci_free_irq_vectors(dev);

This change deserves a line in the commit message.

-- 
With Best Regards,
Andy Shevchenko

[PATCH v2 2/4] Documentation: devres: Add pcim_alloc_irq_vectors()

[Dejin Zheng]

Add pcim_alloc_irq_vectors(), a device-managed version of
pci_alloc_irq_vectors(). introducing this function can simplify
the error handling path in many drivers.

Signed-off-by: Dejin Zheng <zhengdejin5@gmail.com>
---
v1 -> v2:
	- Modify some commit messages.

 Documentation/driver-api/driver-model/devres.rst | 1 +
 1 file changed, 1 insertion(+)

diff --git a/Documentation/driver-api/driver-model/devres.rst b/Documentation/driver-api/driver-model/devres.rst
index cd8b6e657b94..a52f65b6352f 100644
--- a/Documentation/driver-api/driver-model/devres.rst
+++ b/Documentation/driver-api/driver-model/devres.rst
@@ -380,6 +380,7 @@ PCI
   devm_pci_alloc_host_bridge()  : managed PCI host bridge allocation
   devm_pci_remap_cfgspace()	: ioremap PCI configuration space
   devm_pci_remap_cfg_resource()	: ioremap PCI configuration space resource
+  pcim_alloc_irq_vectors()      : managed IRQ vectors allocation
   pcim_enable_device()		: after success, all PCI ops become managed
   pcim_pin_device()		: keep PCI device enabled after release
 
-- 
2.25.0

[PATCH v2 3/4] i2c: designware: Use the correct name of device-managed function

[Dejin Zheng]

Use the new function pcim_alloc_irq_vectors() to allocate IRQ vectors,
the pcim_alloc_irq_vectors() function, an explicit device-managed version
of pci_alloc_irq_vectors(). If pcim_enable_device() has been called
before, then pci_alloc_irq_vectors() is actually a device-managed
function. It is used here as a device-managed function, So replace it
with pcim_alloc_irq_vectors().

Signed-off-by: Dejin Zheng <zhengdejin5@gmail.com>
---
v1 -> v2:
	- Modify some commit messages.

 drivers/i2c/busses/i2c-designware-pcidrv.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/i2c/busses/i2c-designware-pcidrv.c b/drivers/i2c/busses/i2c-designware-pcidrv.c
index 55c83a7a24f3..444533be49ee 100644
--- a/drivers/i2c/busses/i2c-designware-pcidrv.c
+++ b/drivers/i2c/busses/i2c-designware-pcidrv.c
@@ -219,7 +219,7 @@ static int i2c_dw_pci_probe(struct pci_dev *pdev,
 	if (!dev)
 		return -ENOMEM;
 
-	r = pci_alloc_irq_vectors(pdev, 1, 1, PCI_IRQ_ALL_TYPES);
+	r = pcim_alloc_irq_vectors(pdev, 1, 1, PCI_IRQ_ALL_TYPES);
 	if (r < 0)
 		return r;
 
-- 
2.25.0

Re: [PATCH v2 3/4] i2c: designware: Use the correct name of device-managed function

[Andy Shevchenko]

On Tue, Feb 16, 2021 at 10:18:09PM +0800, Dejin Zheng wrote:
> Use the new function pcim_alloc_irq_vectors() to allocate IRQ vectors,
> the pcim_alloc_irq_vectors() function, an explicit device-managed version
> of pci_alloc_irq_vectors(). If pcim_enable_device() has been called
> before, then pci_alloc_irq_vectors() is actually a device-managed
> function. It is used here as a device-managed function, So replace it
> with pcim_alloc_irq_vectors().

...

> -	r = pci_alloc_irq_vectors(pdev, 1, 1, PCI_IRQ_ALL_TYPES);
> +	r = pcim_alloc_irq_vectors(pdev, 1, 1, PCI_IRQ_ALL_TYPES);
>  	if (r < 0)
>  		return r;

It's good, but now why do we have pci_free_irq_vectors() in the same file?


-- 
With Best Regards,
Andy Shevchenko

Re: [PATCH v2 3/4] i2c: designware: Use the correct name of device-managed function

[Dejin Zheng]

On Tue, Feb 16, 2021 at 04:39:09PM +0200, Andy Shevchenko wrote:
> On Tue, Feb 16, 2021 at 10:18:09PM +0800, Dejin Zheng wrote:
> > Use the new function pcim_alloc_irq_vectors() to allocate IRQ vectors,
> > the pcim_alloc_irq_vectors() function, an explicit device-managed version
> > of pci_alloc_irq_vectors(). If pcim_enable_device() has been called
> > before, then pci_alloc_irq_vectors() is actually a device-managed
> > function. It is used here as a device-managed function, So replace it
> > with pcim_alloc_irq_vectors().
> 
> ...
> 
> > -	r = pci_alloc_irq_vectors(pdev, 1, 1, PCI_IRQ_ALL_TYPES);
> > +	r = pcim_alloc_irq_vectors(pdev, 1, 1, PCI_IRQ_ALL_TYPES);
> >  	if (r < 0)
> >  		return r;
> 
> It's good, but now why do we have pci_free_irq_vectors() in the same file?
>
Done. and thank you for your careful inspection.


> 
> -- 
> With Best Regards,
> Andy Shevchenko
> 
> 

[PATCH v2 4/4] i2c: thunderx: Use the correct name of device-managed function

[Dejin Zheng]

Use the new function pcim_alloc_irq_vectors() to allocate IRQ vectors,
the pcim_alloc_irq_vectors() function, an explicit device-managed version
of pci_alloc_irq_vectors(). If pcim_enable_device() has been called
before, then pci_alloc_irq_vectors() is actually a device-managed
function. It is used here as a device-managed function, So replace it
with pcim_alloc_irq_vectors().

Signed-off-by: Dejin Zheng <zhengdejin5@gmail.com>
---
v1 -> v2:
	- Modify some commit messages.

 drivers/i2c/busses/i2c-thunderx-pcidrv.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/i2c/busses/i2c-thunderx-pcidrv.c b/drivers/i2c/busses/i2c-thunderx-pcidrv.c
index 12c90aa0900e..63354e9fb726 100644
--- a/drivers/i2c/busses/i2c-thunderx-pcidrv.c
+++ b/drivers/i2c/busses/i2c-thunderx-pcidrv.c
@@ -192,7 +192,7 @@ static int thunder_i2c_probe_pci(struct pci_dev *pdev,
 	i2c->hlc_int_enable = thunder_i2c_hlc_int_enable;
 	i2c->hlc_int_disable = thunder_i2c_hlc_int_disable;
 
-	ret = pci_alloc_irq_vectors(pdev, 1, 1, PCI_IRQ_MSIX);
+	ret = pcim_alloc_irq_vectors(pdev, 1, 1, PCI_IRQ_MSIX);
 	if (ret < 0)
 		goto error;
 
-- 
2.25.0