On Mon, Aug 3, 2020 at 8:46 AM Pali Rohár <pali@xxxxxxxxxx> wrote:
>
> On Wednesday 29 July 2020 12:48:09 Rob Herring wrote:
> > On Wed, Jul 15, 2020 at 04:25:56PM +0200, Marek Behún wrote:
> > > From: Pali Rohár <pali@xxxxxxxxxx>
> > >
> > > Providing driver's 'remove' function allows kernel to bind and unbind devices
> > > from aardvark driver. It also allows to build aardvark driver as a module.
> > >
> > > Compiling aardvark as a module simplifies development and debugging of
> > > this driver as it can be reloaded at runtime without the need to reboot
> > > to new kernel.
> > >
> > > Signed-off-by: Pali Rohár <pali@xxxxxxxxxx>
> > > Reviewed-by: Marek Behún <marek.behun@xxxxxx>
> > > ---
> > > drivers/pci/controller/Kconfig | 2 +-
> > > drivers/pci/controller/pci-aardvark.c | 25 ++++++++++++++++++++++---
> > > 2 files changed, 23 insertions(+), 4 deletions(-)
> > >
> > > diff --git a/drivers/pci/controller/Kconfig b/drivers/pci/controller/Kconfig
> > > index adddf21fa381..f9da5ff2c517 100644
> > > --- a/drivers/pci/controller/Kconfig
> > > +++ b/drivers/pci/controller/Kconfig
> > > @@ -12,7 +12,7 @@ config PCI_MVEBU
> > > select PCI_BRIDGE_EMUL
> > >
> > > config PCI_AARDVARK
> > > - bool "Aardvark PCIe controller"
> > > + tristate "Aardvark PCIe controller"
> > > depends on (ARCH_MVEBU && ARM64) || COMPILE_TEST
> > > depends on OF
> > > depends on PCI_MSI_IRQ_DOMAIN
> > > diff --git a/drivers/pci/controller/pci-aardvark.c b/drivers/pci/controller/pci-aardvark.c
> > > index d5f58684d962..0a5aa6d77f5d 100644
> > > --- a/drivers/pci/controller/pci-aardvark.c
> > > +++ b/drivers/pci/controller/pci-aardvark.c
> > > @@ -14,6 +14,7 @@
> > > #include <linux/irq.h>
> > > #include <linux/irqdomain.h>
> > > #include <linux/kernel.h>
> > > +#include <linux/module.h>
> > > #include <linux/pci.h>
> > > #include <linux/init.h>
> > > #include <linux/phy/phy.h>
> > > @@ -1114,6 +1115,7 @@ static int advk_pcie_probe(struct platform_device *pdev)
> > >
> > > pcie = pci_host_bridge_priv(bridge);
> > > pcie->pdev = pdev;
> > > + platform_set_drvdata(pdev, pcie);
> > >
> > > res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> > > pcie->base = devm_ioremap_resource(dev, res);
> > > @@ -1204,18 +1206,35 @@ static int advk_pcie_probe(struct platform_device *pdev)
> > > return 0;
> > > }
> > >
> > > +static int advk_pcie_remove(struct platform_device *pdev)
> > > +{
> > > + struct advk_pcie *pcie = platform_get_drvdata(pdev);
> > > + struct pci_host_bridge *bridge = pci_host_bridge_from_priv(pcie);
> > > +
> > > + pci_stop_root_bus(bridge->bus);
> > > + pci_remove_root_bus(bridge->bus);
> >
> > Based on pci_host_common_remove() implementation, doesn't this need a
> > lock around it (pci_lock_rescan_remove)?
>
> Well, I'm not sure. I looked into other pci drivers and none of
> following drivers pci-tegra.c, pcie-altera.c, pcie-brcmstb.c,
> pcie-iproc.c, pcie-mediatek.c, pcie-rockchip-host.c calls
> pci_lock_rescan_remove() and pci_unlock_rescan_remove().
The mutex protects the bus->devices list, so yes I believe it is needed.
Rob
