| Message ID | 1376333215-12885-4-git-send-email-sebastian.hesselbarth@gmail.com (mailing list archive) |
|---|---|
| State | New, archived |
| Delegated to: | Bjorn Helgaas |
| Headers | show |
Dear Sebastian Hesselbarth, On Mon, 12 Aug 2013 20:46:49 +0200, Sebastian Hesselbarth wrote: > This removes the subsys_initcall from the driver and converts it to > a normal platform_driver. Also, drvdata is set and a remove functions > is added to disable the clock and free resources. > > Signed-off-by: Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com> I'm OK with this, just a comment below. > +static int mvebu_pcie_remove(struct platform_device *pdev) > +{ > + struct mvebu_pcie *pcie = platform_get_drvdata(pdev); > + struct mvebu_pcie_port *port = &pcie->ports[0]; > + int i; > + > + for (i = 0; i < pcie->nports; i++, port++) { > + clk_disable_unprepare(port->clk); > + kfree(port->name); > + } > + > + return 0; > +} I believe the ->remove() part is quite useless. The driver is a 'bool' in Kconfig, so it cannot be compiled as a module, and I'm not sure there a way to remove the platform device that corresponds to the PCIe controller. And even if there was, then it would still not work because as far as I know, the ARM PCI core doesn't provide functions to 'unregister' PCI controllers, so it would keep pointers to functions located in the driver, which would cause nasty things when unloading the module. So the reason why I didn't include a ->remove() hook is simply because there was, as of today, no use for it. Best regards, Thomas
On Tue, Aug 13, 2013 at 09:19:59AM +0200, Thomas Petazzoni wrote: > Dear Sebastian Hesselbarth, > > On Mon, 12 Aug 2013 20:46:49 +0200, Sebastian Hesselbarth wrote: > > This removes the subsys_initcall from the driver and converts it to > > a normal platform_driver. Also, drvdata is set and a remove functions > > is added to disable the clock and free resources. > > > > Signed-off-by: Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com> > > I'm OK with this, just a comment below. > > > +static int mvebu_pcie_remove(struct platform_device *pdev) > > +{ > > + struct mvebu_pcie *pcie = platform_get_drvdata(pdev); > > + struct mvebu_pcie_port *port = &pcie->ports[0]; > > + int i; > > + > > + for (i = 0; i < pcie->nports; i++, port++) { > > + clk_disable_unprepare(port->clk); > > + kfree(port->name); > > + } > > + > > + return 0; > > +} > > I believe the ->remove() part is quite useless. The driver is a 'bool' > in Kconfig, so it cannot be compiled as a module, and I'm not sure > there a way to remove the platform device that corresponds to the PCIe > controller. There is. You can write the device's name to the driver's unbind file in sysfs. What I ended up doing for Tegra was not to provide a .remove() at all and set the struct device_driver's .suppress_bind_attrs to true. Those two things combined should make it impossible to unbind the device from the driver. > And even if there was, then it would still not work because as far as I > know, the ARM PCI core doesn't provide functions to 'unregister' PCI > controllers, so it would keep pointers to functions located in the > driver, which would cause nasty things when unloading the module. I did some initial work to support driver unbinding (in order to support module unloading) on Tegra and things look pretty promising. The ARM PCI code would need something like pci_common_exit() to make sure there are no leaks. Unfortunately I can't seem to find that branch anymore, so I will have to reconstruct it from memory... That said, I agree with Thomas that it's not useful (and potentially even dangerous) to add the .remove() at this point in time. Thierry
On 08/13/13 10:06, Thierry Reding wrote: > On Tue, Aug 13, 2013 at 09:19:59AM +0200, Thomas Petazzoni wrote: >> On Mon, 12 Aug 2013 20:46:49 +0200, Sebastian Hesselbarth wrote: >>> This removes the subsys_initcall from the driver and converts it to >>> a normal platform_driver. Also, drvdata is set and a remove functions >>> is added to disable the clock and free resources. >>> >>> Signed-off-by: Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com> >> >> I'm OK with this, just a comment below. >> >>> +static int mvebu_pcie_remove(struct platform_device *pdev) >>> +{ >>> + struct mvebu_pcie *pcie = platform_get_drvdata(pdev); >>> + struct mvebu_pcie_port *port = &pcie->ports[0]; >>> + int i; >>> + >>> + for (i = 0; i < pcie->nports; i++, port++) { >>> + clk_disable_unprepare(port->clk); >>> + kfree(port->name); >>> + } >>> + >>> + return 0; >>> +} >> >> I believe the ->remove() part is quite useless. The driver is a 'bool' >> in Kconfig, so it cannot be compiled as a module, and I'm not sure >> there a way to remove the platform device that corresponds to the PCIe >> controller. > > There is. You can write the device's name to the driver's unbind file in > sysfs. What I ended up doing for Tegra was not to provide a .remove() at > all and set the struct device_driver's .suppress_bind_attrs to true. [...] > That said, I agree with Thomas that it's not useful (and potentially > even dangerous) to add the .remove() at this point in time. Thierry, Thomas, I will not introduce the .remove and set .suppress_bind_attrs = true as Thierry suggested. Sebastian -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/pci/host/pci-mvebu.c b/drivers/pci/host/pci-mvebu.c index 0a359d7..2370b59 100644 --- a/drivers/pci/host/pci-mvebu.c +++ b/drivers/pci/host/pci-mvebu.c @@ -165,7 +165,7 @@ static void mvebu_pcie_set_local_dev_nr(struct mvebu_pcie_port *port, int nr) * BAR[0,2] -> disabled, BAR[1] -> covers all DRAM banks * WIN[0-3] -> DRAM bank[0-3] */ -static void __init mvebu_pcie_setup_wins(struct mvebu_pcie_port *port) +static void mvebu_pcie_setup_wins(struct mvebu_pcie_port *port) { const struct mbus_dram_target_info *dram; u32 size; @@ -217,7 +217,7 @@ static void __init mvebu_pcie_setup_wins(struct mvebu_pcie_port *port) port->base + PCIE_BAR_CTRL_OFF(1)); } -static void __init mvebu_pcie_setup_hw(struct mvebu_pcie_port *port) +static void mvebu_pcie_setup_hw(struct mvebu_pcie_port *port) { u16 cmd; u32 mask; @@ -628,7 +628,7 @@ static struct pci_ops mvebu_pcie_ops = { .write = mvebu_pcie_wr_conf, }; -static int __init mvebu_pcie_setup(int nr, struct pci_sys_data *sys) +static int mvebu_pcie_setup(int nr, struct pci_sys_data *sys) { struct mvebu_pcie *pcie = sys_to_pcie(sys); int i; @@ -647,7 +647,7 @@ static int __init mvebu_pcie_setup(int nr, struct pci_sys_data *sys) return 1; } -static int __init mvebu_pcie_map_irq(const struct pci_dev *dev, u8 slot, u8 pin) +static int mvebu_pcie_map_irq(const struct pci_dev *dev, u8 slot, u8 pin) { struct of_irq oirq; int ret; @@ -704,7 +704,7 @@ resource_size_t mvebu_pcie_align_resource(struct pci_dev *dev, return start; } -static void __init mvebu_pcie_enable(struct mvebu_pcie *pcie) +static void mvebu_pcie_enable(struct mvebu_pcie *pcie) { struct hw_pci hw; @@ -727,10 +727,8 @@ static void __init mvebu_pcie_enable(struct mvebu_pcie *pcie) * <...> property for one that matches the given port/lane. Once * found, maps it. */ -static void __iomem * __init -mvebu_pcie_map_registers(struct platform_device *pdev, - struct device_node *np, - struct mvebu_pcie_port *port) +static void __iomem *mvebu_pcie_map_registers(struct platform_device *pdev, + struct device_node *np, struct mvebu_pcie_port *port) { struct resource regs; int ret = 0; @@ -786,7 +784,7 @@ static int mvebu_get_tgt_attr(struct device_node *np, int devfn, return -ENOENT; } -static void __init mvebu_pcie_msi_enable(struct mvebu_pcie *pcie) +static void mvebu_pcie_msi_enable(struct mvebu_pcie *pcie) { struct device_node *msi_node; @@ -801,7 +799,7 @@ static void __init mvebu_pcie_msi_enable(struct mvebu_pcie *pcie) pcie->msi->dev = &pcie->pdev->dev; } -static int __init mvebu_pcie_probe(struct platform_device *pdev) +static int mvebu_pcie_probe(struct platform_device *pdev) { struct mvebu_pcie *pcie; struct device_node *np = pdev->dev.of_node; @@ -814,6 +812,7 @@ static int __init mvebu_pcie_probe(struct platform_device *pdev) return -ENOMEM; pcie->pdev = pdev; + platform_set_drvdata(pdev, pcie); /* Get the PCIe memory and I/O aperture */ mvebu_mbus_get_pcie_mem_aperture(&pcie->mem); @@ -939,6 +938,20 @@ static int __init mvebu_pcie_probe(struct platform_device *pdev) return 0; } +static int mvebu_pcie_remove(struct platform_device *pdev) +{ + struct mvebu_pcie *pcie = platform_get_drvdata(pdev); + struct mvebu_pcie_port *port = &pcie->ports[0]; + int i; + + for (i = 0; i < pcie->nports; i++, port++) { + clk_disable_unprepare(port->clk); + kfree(port->name); + } + + return 0; +} + static const struct of_device_id mvebu_pcie_of_match_table[] = { { .compatible = "marvell,armada-xp-pcie", }, { .compatible = "marvell,armada-370-pcie", }, @@ -954,15 +967,10 @@ static struct platform_driver mvebu_pcie_driver = { .of_match_table = of_match_ptr(mvebu_pcie_of_match_table), }, + .probe = mvebu_pcie_probe, + .remove = mvebu_pcie_remove, }; - -static int __init mvebu_pcie_init(void) -{ - return platform_driver_probe(&mvebu_pcie_driver, - mvebu_pcie_probe); -} - -subsys_initcall(mvebu_pcie_init); +module_platform_driver(mvebu_pcie_driver); MODULE_AUTHOR("Thomas Petazzoni <thomas.petazzoni@free-electrons.com>"); MODULE_DESCRIPTION("Marvell EBU PCIe driver");
This removes the subsys_initcall from the driver and converts it to a normal platform_driver. Also, drvdata is set and a remove functions is added to disable the clock and free resources. Signed-off-by: Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com> --- Cc: Russell King <linux@arm.linux.org.uk> Cc: Jason Cooper <jason@lakedaemon.net> Cc: Andrew Lunn <andrew@lunn.ch> Cc: Bjorn Helgaas <bhelgaas@google.com> Cc: Thomas Petazzoni <thomas.petazzoni@free-electrons.com> Cc: linux-kernel@vger.kernel.org Cc: linux-arm-kernel@lists.infradead.org Cc: linux-pci@vger.kernel.org --- drivers/pci/host/pci-mvebu.c | 46 +++++++++++++++++++++++++----------------- 1 file changed, 27 insertions(+), 19 deletions(-)