Re: [PATCH 1/2] PCI: generic: Refactor code to enable reuse by other drivers.

Will Deacon
2015-12-22T10:07:33Z

On Mon, Dec 21, 2015 at 05:53:41PM -0800, David Daney wrote:
> From: David Daney <david.daney-YGCgFSpz5w/QT0dZR+AlfA@public.gmane.org>
>
> No change in functionality.
>
> Move structure definitions into a separate header file. Split probe
> function in to two parts:
>
> - a small driver specific probe function (gen_pci_probe)
>
> - a common probe that can be used by other drivers
> (gen_pci_common_probe)
>
> Signed-off-by: David Daney <david.daney-YGCgFSpz5w/QT0dZR+AlfA@public.gmane.org>
> ---
> drivers/pci/host/pci-host-generic.c | 53 ++++++++++++-----------------------
> drivers/pci/host/pci-host-generic.h | 56 +++++++++++++++++++++++++++++++++++++
> 2 files changed, 74 insertions(+), 35 deletions(-)
> create mode 100644 drivers/pci/host/pci-host-generic.h
>
> diff --git a/drivers/pci/host/pci-host-generic.c b/drivers/pci/host/pci-host-generic.c
> index 5434c90..e83cec7 100644
> --- a/drivers/pci/host/pci-host-generic.c
> +++ b/drivers/pci/host/pci-host-generic.c
> @@ -25,33 +25,7 @@
> #include <linux/of_pci.h>
> #include <linux/platform_device.h>
>
> -struct gen_pci_cfg_bus_ops {
> - u32 bus_shift;
> - struct pci_ops ops;
> -};
> -
> -struct gen_pci_cfg_windows {
> - struct resource res;
> - struct resource *bus_range;
> - void __iomem **win;
> -
> - struct gen_pci_cfg_bus_ops *ops;
> -};
> -
> -/*
> - * ARM pcibios functions expect the ARM struct pci_sys_data as the PCI
> - * sysdata. Add pci_sys_data as the first element in struct gen_pci so
> - * that when we use a gen_pci pointer as sysdata, it is also a pointer to
> - * a struct pci_sys_data.
> - */
> -struct gen_pci {
> -#ifdef CONFIG_ARM
> - struct pci_sys_data sys;
> -#endif
> - struct pci_host_bridge host;
> - struct gen_pci_cfg_windows cfg;
> - struct list_head resources;
> -};
> +#include "pci-host-generic.h"
>
> static void __iomem *gen_pci_map_cfg_bus_cam(struct pci_bus *bus,
> unsigned int devfn,
> @@ -208,19 +182,15 @@ static int gen_pci_parse_map_cfg_windows(struct gen_pci *pci)
> return 0;
> }
>
> -static int gen_pci_probe(struct platform_device *pdev)
> +int gen_pci_common_probe(struct platform_device *pdev,
> + struct gen_pci *pci)

Whilst I'm fine with this patch, I don't know how Bjorn will feel about
exposing this function outside of the generic host driver. We could avoid
it by turning things upside-down and having the generic driver probe
the other drivers by matching a compatible string with a probe function
pointer, but I'd be interested to see what others think.

Will