Re: [PATCH] i2c: piix4: Add second SMBus for X370/X470/X570

From: Jean Delvare
Date: Tue Apr 14 2020 - 03:42:08 EST


Hi Sebastian,

On Mon, 13 Apr 2020 17:06:34 +0200, Sebastian Reichel wrote:
> The second interface can be found on X370, X470 and X570 according
> to the bugzilla entry. I only tested with X570 on an ASRock X570
> Taichi:
>
> $ lspci -nnv -d 1022:790b
> 00:14.0 SMBus [0c05]: Advanced Micro Devices, Inc. [AMD] FCH SMBus Controller [1022:790b] (rev 61)
> Subsystem: ASRock Incorporation FCH SMBus Controller [1849:ffff]
> Flags: 66MHz, medium devsel
> Kernel driver in use: piix4_smbus
> Kernel modules: i2c_piix4, sp5100_tco
>
> Before the patch:
>
> $ i2cdetect -l | grep PIIX4
> i2c-1 unknown SMBus PIIX4 adapter port 2 at 0b00 N/A
> i2c-0 unknown SMBus PIIX4 adapter port 0 at 0b00 N/A
>
> After the patch:
>
> $ i2cdetect -l | grep PIIX4
> i2c-1 unknown SMBus PIIX4 adapter port 2 at 0b00 N/A
> i2c-2 unknown SMBus PIIX4 adapter port 1 at 0b20 N/A
> i2c-0 unknown SMBus PIIX4 adapter port 0 at 0b00 N/A
>
> Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=202587
> Reported-by: Adam Honse <calcprogrammer1@xxxxxxxxx>
> Signed-off-by: Sebastian Reichel <sebastian.reichel@xxxxxxxxxxxxx>
> ---
> Hi,
>
> The Bugzilla entry contains a second change, which reduces the timeouts
> for quicker operation. I did not include that change, since I do not know
> if this is a good idea for all devices supported by this driver. In any
> case it should be a separate patch. Let's get the interface working for
> now.
>
> -- Sebastian
> ---
> drivers/i2c/busses/i2c-piix4.c | 8 +++++---
> 1 file changed, 5 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/i2c/busses/i2c-piix4.c b/drivers/i2c/busses/i2c-piix4.c
> index 30ded6422e7b..3e89143a0ecf 100644
> --- a/drivers/i2c/busses/i2c-piix4.c
> +++ b/drivers/i2c/busses/i2c-piix4.c
> @@ -976,9 +976,11 @@ static int piix4_probe(struct pci_dev *dev, const struct pci_device_id *id)
> }
> }
>
> - if (dev->vendor == PCI_VENDOR_ID_AMD &&
> - dev->device == PCI_DEVICE_ID_AMD_HUDSON2_SMBUS) {
> - retval = piix4_setup_sb800(dev, id, 1);
> + if (dev->vendor == PCI_VENDOR_ID_AMD) {
> + if (dev->device == PCI_DEVICE_ID_AMD_HUDSON2_SMBUS ||
> + dev->device == PCI_DEVICE_ID_AMD_KERNCZ_SMBUS) {
> + retval = piix4_setup_sb800(dev, id, 1);
> + }
> }
>
> if (retval > 0) {

Adam just sent pretty much the same patch:

https://patchwork.ozlabs.org/project/linux-i2c/patch/20200410204843.3856-1-calcprogrammer1@xxxxxxxxx/

Reviewed-by: Jean Delvare <jdelvare@xxxxxxx>

I'll leave it to Wolfram which one he wants to apply.

--
Jean Delvare
SUSE L3 Support