Intel EG20T PCH has UART device which is compatible with 8250.
Currently, with general configuration, the PCH UART driver is not loaded but 8250 standard driver is loaded.
Therefore, in case of using PCH UART driver, need to disable 8250 pci function.
However, this procedure is not best solution.
This patch, in 8250_pci, if the device is the PCH or the family IOH,
'-ENODEV' is returned.
As a result, disabling 8250-pci processing becomes unnecessary.
Signed-off-by: Tomoya MORINAGA <[email protected]>
---
drivers/tty/serial/8250_pci.c | 13 +++++++++++++
1 files changed, 13 insertions(+), 0 deletions(-)
diff --git a/drivers/tty/serial/8250_pci.c b/drivers/tty/serial/8250_pci.c
index 738cec9..2678d9d 100644
--- a/drivers/tty/serial/8250_pci.c
+++ b/drivers/tty/serial/8250_pci.c
@@ -2559,6 +2559,19 @@ pciserial_init_one(struct pci_dev *dev, const struct pci_device_id *ent)
return -EINVAL;
}
+#if defined(CONFIG_SERIAL_PCH_UART) || defined(CONFIG_SERIAL_PCH_UART_MODULE)
+ if ((dev->vendor == PCI_VENDOR_ID_INTEL && dev->device == 0x8811) ||
+ (dev->vendor == PCI_VENDOR_ID_INTEL && dev->device == 0x8812) ||
+ (dev->vendor == PCI_VENDOR_ID_INTEL && dev->device == 0x8813) ||
+ (dev->vendor == PCI_VENDOR_ID_INTEL && dev->device == 0x8814) ||
+ (dev->vendor == 0x10DB && dev->device == 0x8027) ||
+ (dev->vendor == 0x10DB && dev->device == 0x8028) ||
+ (dev->vendor == 0x10DB && dev->device == 0x8029) ||
+ (dev->vendor == 0x10DB && dev->device == 0x800C) ||
+ (dev->vendor == 0x10DB && dev->device == 0x800D))
+ return -ENODEV;
+#endif
+
board = &pci_boards[ent->driver_data];
rc = pci_enable_device(dev);
--
1.7.4
On Mon, May 30, 2011 at 04:42:04PM +0900, Tomoya MORINAGA wrote:
> Intel EG20T PCH has UART device which is compatible with 8250.
> Currently, with general configuration, the PCH UART driver is not loaded but 8250 standard driver is loaded.
> Therefore, in case of using PCH UART driver, need to disable 8250 pci function.
> However, this procedure is not best solution.
>
> This patch, in 8250_pci, if the device is the PCH or the family IOH,
> '-ENODEV' is returned.
> As a result, disabling 8250-pci processing becomes unnecessary.
>
> Signed-off-by: Tomoya MORINAGA <[email protected]>
> ---
> drivers/tty/serial/8250_pci.c | 13 +++++++++++++
> 1 files changed, 13 insertions(+), 0 deletions(-)
>
> diff --git a/drivers/tty/serial/8250_pci.c b/drivers/tty/serial/8250_pci.c
> index 738cec9..2678d9d 100644
> --- a/drivers/tty/serial/8250_pci.c
> +++ b/drivers/tty/serial/8250_pci.c
> @@ -2559,6 +2559,19 @@ pciserial_init_one(struct pci_dev *dev, const struct pci_device_id *ent)
> return -EINVAL;
> }
>
> +#if defined(CONFIG_SERIAL_PCH_UART) || defined(CONFIG_SERIAL_PCH_UART_MODULE)
> + if ((dev->vendor == PCI_VENDOR_ID_INTEL && dev->device == 0x8811) ||
> + (dev->vendor == PCI_VENDOR_ID_INTEL && dev->device == 0x8812) ||
> + (dev->vendor == PCI_VENDOR_ID_INTEL && dev->device == 0x8813) ||
> + (dev->vendor == PCI_VENDOR_ID_INTEL && dev->device == 0x8814) ||
> + (dev->vendor == 0x10DB && dev->device == 0x8027) ||
> + (dev->vendor == 0x10DB && dev->device == 0x8028) ||
> + (dev->vendor == 0x10DB && dev->device == 0x8029) ||
> + (dev->vendor == 0x10DB && dev->device == 0x800C) ||
> + (dev->vendor == 0x10DB && dev->device == 0x800D))
> + return -ENODEV;
> +#endif
Why put this with an #if around it? Why not just always not bind to
this driver as we have a "correct" driver for the hardware now?
thanks,
greg k-h
On Monday, May 30, 2011 4:47 PM, Greg KH wrote:
> Why put this with an #if around it?
> Why not just always not
> bind to this driver as we have a "correct" driver for the
> hardware now?
Let me clarify your saying.
Which does your saying mean, (1) or (2) or else?
(1)
> +#if defined(CONFIG_SERIAL_PCH_UART) || defined(CONFIG_SERIAL_PCH_UART_MODULE)
> + return -ENODEV;
> +#endif
(2)
> + if ((dev->vendor == PCI_VENDOR_ID_INTEL && dev->device == 0x8811) ||
> + (dev->vendor == PCI_VENDOR_ID_INTEL && dev->device == 0x8812) ||
> + (dev->vendor == PCI_VENDOR_ID_INTEL && dev->device == 0x8813) ||
> + (dev->vendor == PCI_VENDOR_ID_INTEL && dev->device == 0x8814) ||
> + (dev->vendor == 0x10DB && dev->device == 0x8027) ||
> + (dev->vendor == 0x10DB && dev->device == 0x8028) ||
> + (dev->vendor == 0x10DB && dev->device == 0x8029) ||
> + (dev->vendor == 0x10DB && dev->device == 0x800C) ||
> + (dev->vendor == 0x10DB && dev->device == 0x800D))
> + return -ENODEV;
With Best Regards,
-----------------------------------------
Tomoya MORINAGA
OKI SEMICONDUCTOR CO., LTD.
On Mon, May 30, 2011 at 05:17:19PM +0900, Tomoya MORINAGA wrote:
> On Monday, May 30, 2011 4:47 PM, Greg KH wrote:
>
> > Why put this with an #if around it?
> > Why not just always not
> > bind to this driver as we have a "correct" driver for the
> > hardware now?
>
> Let me clarify your saying.
> Which does your saying mean, (1) or (2) or else?
>
> (1)
> > +#if defined(CONFIG_SERIAL_PCH_UART) || defined(CONFIG_SERIAL_PCH_UART_MODULE)
> > + return -ENODEV;
> > +#endif
>
> (2)
> > + if ((dev->vendor == PCI_VENDOR_ID_INTEL && dev->device == 0x8811) ||
> > + (dev->vendor == PCI_VENDOR_ID_INTEL && dev->device == 0x8812) ||
> > + (dev->vendor == PCI_VENDOR_ID_INTEL && dev->device == 0x8813) ||
> > + (dev->vendor == PCI_VENDOR_ID_INTEL && dev->device == 0x8814) ||
> > + (dev->vendor == 0x10DB && dev->device == 0x8027) ||
> > + (dev->vendor == 0x10DB && dev->device == 0x8028) ||
> > + (dev->vendor == 0x10DB && dev->device == 0x8029) ||
> > + (dev->vendor == 0x10DB && dev->device == 0x800C) ||
> > + (dev->vendor == 0x10DB && dev->device == 0x800D))
> > + return -ENODEV;
(2)
Just don't put the #if check in the .c file at all, and always compile
in the "quirk" table.
Even better yet, use the proper quirk table structure in the driver
already to cause the driver to not be bound to these devices, that's
what it is there for, right?
thanks,
greg k-h
On Mon, 30 May 2011 15:47:22 +0800
Greg KH <[email protected]> wrote:
> On Mon, May 30, 2011 at 04:42:04PM +0900, Tomoya MORINAGA wrote:
> > Intel EG20T PCH has UART device which is compatible with 8250.
> > Currently, with general configuration, the PCH UART driver is not
> > loaded but 8250 standard driver is loaded. Therefore, in case of
> > using PCH UART driver, need to disable 8250 pci function. However,
> > this procedure is not best solution.
> >
> > This patch, in 8250_pci, if the device is the PCH or the family IOH,
> > '-ENODEV' is returned.
> > As a result, disabling 8250-pci processing becomes unnecessary.
> >
> > Signed-off-by: Tomoya MORINAGA <[email protected]>
> > ---
> > drivers/tty/serial/8250_pci.c | 13 +++++++++++++
> > 1 files changed, 13 insertions(+), 0 deletions(-)
> >
> > diff --git a/drivers/tty/serial/8250_pci.c
> > b/drivers/tty/serial/8250_pci.c index 738cec9..2678d9d 100644
> > --- a/drivers/tty/serial/8250_pci.c
> > +++ b/drivers/tty/serial/8250_pci.c
> > @@ -2559,6 +2559,19 @@ pciserial_init_one(struct pci_dev *dev,
> > const struct pci_device_id *ent) return -EINVAL;
> > }
> >
> > +#if defined(CONFIG_SERIAL_PCH_UART) ||
> > defined(CONFIG_SERIAL_PCH_UART_MODULE)
> > + if ((dev->vendor == PCI_VENDOR_ID_INTEL && dev->device ==
> > 0x8811) ||
> > + (dev->vendor == PCI_VENDOR_ID_INTEL && dev->device ==
> > 0x8812) ||
> > + (dev->vendor == PCI_VENDOR_ID_INTEL && dev->device ==
> > 0x8813) ||
> > + (dev->vendor == PCI_VENDOR_ID_INTEL && dev->device ==
> > 0x8814) ||
> > + (dev->vendor == 0x10DB && dev->device == 0x8027) ||
> > + (dev->vendor == 0x10DB && dev->device == 0x8028) ||
> > + (dev->vendor == 0x10DB && dev->device == 0x8029) ||
> > + (dev->vendor == 0x10DB && dev->device == 0x800C) ||
> > + (dev->vendor == 0x10DB && dev->device == 0x800D))
> > + return -ENODEV;
> > +#endif
>
> Why put this with an #if around it? Why not just always not bind to
> this driver as we have a "correct" driver for the hardware now?
Because if the PCH driver is not available you want to bind it to the
8250 driver, which also works with it but less efficiently.
The giant if probably should be a pci match table however
Alan
Hi Greg
> Because if the PCH driver is not available you want to bind
> it to the 8250 driver, which also works with it but less efficiently.
>
> The giant if probably should be a pci match table however
Which opinions should I select ?
Though Alan's comment has a point,
IMHO, in probe processing, the efficiently is not so important.
Adding the "#ifdef", I think, readability of 8250_pci.c goes down.
Thanks,
-----------------------------------------
Tomoya MORINAGA
OKI SEMICONDUCTOR CO., LTD.