Messages in this thread | | | Date | Fri, 16 Dec 2022 11:38:43 +0200 | From | Andy Shevchenko <> | Subject | Re: [PATCH v9 tty-next 2/4] serial: 8250_pci1xxxx: Add driver for quad-uart support |
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On Fri, Dec 16, 2022 at 09:30:42AM +0000, Tharunkumar.Pasumarthi@microchip.com wrote: > > From: Andy Shevchenko <andriy.shevchenko@linux.intel.com> > > Sent: Friday, December 16, 2022 1:56 PM
...
> > > > > + pci_iounmap(pdev, priv->membase); > > > > > > > > Here is inconsistency on how you interpret pci_*() calls when > > > > pcim_enable_device() has been used. I.e. for IRQ you don't > > > > deallocate resources explicitly (yes, it's done automatically > > > > anyway), but you explicitly call pci_iounmap(). Choose a single approach > > for all of them. > > > > > > AFAIK call to pci_iounmap cannot be avoided since pci_ioremap_bar is not > > 'managed' API. > > > You suggest calling pci_free_irq_vectors (even though it is not mandatory)? > > > > Why is it not mandatory? > > Following is the reason why I felt calling pci_free_irq_vectors is not > mandatory. Correct me if my understanding is wrong. > > Following is the Callback Sequence (from 6.1 kernel) that gets executed upon > calling pci_alloc_irq_vectors: > pci_alloc_irq_vectors => > pci_alloc_irq_vectors_affinity => > __pci_enable_msi_range => > pci_setup_msi_context => > pcim_setup_msi_release => > > devm_add_action(&dev->dev, pcim_msi_release, dev); > > Inside pcim_msi_release: (called since pcim_enable_device is used) > pci_free_irq_vectors(dev); > > From this sequence, it seemed like, kernel takes care of freeing irq and > calling pci_free_irq_vectors is not required.
Technically you are correct, but... read this discussion, and pay attention to what Christoph said there:
https://lore.kernel.org/linux-serial/0250c46e-da6c-71f3-50ae-b7c17fd0bd2c@siemens.com/
-- With Best Regards, Andy Shevchenko
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