Re: PCI device function not being enumerated [Was: PCMCIA not working on Panasonic Toughbook CF-29]

From: Bjorn Helgaas
Date: Mon Oct 21 2019 - 12:09:55 EST


On Sun, Oct 20, 2019 at 11:08:00AM +0200, Dominik Brodowski wrote:
> On the basis of the additional information (thanks), there might be a
> more specific path to investigate: It is that the PCI code does not
> enumerate the second cardbus bridge PCI function in the more recent 4.19
> kernel compared to the anvient (and working) 2.6 kernel.
>
> Namely, only one CardBus bridge is recognized
>
> ...
> 06:01.0 CardBus bridge: Ricoh Co Ltd RL5c476 II (rev 8b)
> 06:01.1 SD Host controller: Ricoh Co Ltd R5C822 SD/SDIO/MMC/MS/MSPro Host Adapter (rev 11)
> 06:02.0 Network controller: Intel Corporation PRO/Wireless 2915ABG [Calexico2] Network Connection (rev 05)
> ...
>
> instead of the two which really should be present:
>
> ...
> 06:01.0 CardBus bridge: Ricoh Co Ltd RL5c476 II (rev 8b)
> 06:01.1 CardBus bridge: Ricoh Co Ltd RL5c476 II (rev 8b)
> 06:01.2 SD Host controller: Ricoh Co Ltd R5C822 SD/SDIO/MMC/MS/MSPro Host Adapter (rev 11)
> 06:02.0 Network controller: Intel Corporation PRO/Wireless 2915ABG [Calexico2] Network Connection (rev 05)
> ...
>
> To the PCI folks: any idea on what may cause the second cardbus bridge PCI
> device function to be missed? Are there any command line options the users
> who reported this issue[*] may try?

Thanks for the report. Could you try disabling
ricoh_mmc_fixup_rl5c476(), e.g., with the patch below (this is based
on v5.4-rc1, but you can use v4.9 if that's easier for you)? This
isn't a fix; it's just something that looks like it might be related.

> [*] For more information, see this thread:
> https://lore.kernel.org/lkml/CAFjuqNi+knSb9WVQOahCVFyxsiqoGgwoM7Z1aqDBebNzp_-jYw@xxxxxxxxxxxxxx/


diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c
index 320255e5e8f8..7a1e1a242506 100644
--- a/drivers/pci/quirks.c
+++ b/drivers/pci/quirks.c
@@ -3036,38 +3036,6 @@ DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_HINT, 0x0020, quirk_hotplug_bridge);
* #1, and this will confuse the PCI core.
*/
#ifdef CONFIG_MMC_RICOH_MMC
-static void ricoh_mmc_fixup_rl5c476(struct pci_dev *dev)
-{
- u8 write_enable;
- u8 write_target;
- u8 disable;
-
- /*
- * Disable via CardBus interface
- *
- * This must be done via function #0
- */
- if (PCI_FUNC(dev->devfn))
- return;
-
- pci_read_config_byte(dev, 0xB7, &disable);
- if (disable & 0x02)
- return;
-
- pci_read_config_byte(dev, 0x8E, &write_enable);
- pci_write_config_byte(dev, 0x8E, 0xAA);
- pci_read_config_byte(dev, 0x8D, &write_target);
- pci_write_config_byte(dev, 0x8D, 0xB7);
- pci_write_config_byte(dev, 0xB7, disable | 0x02);
- pci_write_config_byte(dev, 0x8E, write_enable);
- pci_write_config_byte(dev, 0x8D, write_target);
-
- pci_notice(dev, "proprietary Ricoh MMC controller disabled (via CardBus function)\n");
- pci_notice(dev, "MMC cards are now supported by standard SDHCI controller\n");
-}
-DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_RICOH, PCI_DEVICE_ID_RICOH_RL5C476, ricoh_mmc_fixup_rl5c476);
-DECLARE_PCI_FIXUP_RESUME_EARLY(PCI_VENDOR_ID_RICOH, PCI_DEVICE_ID_RICOH_RL5C476, ricoh_mmc_fixup_rl5c476);
-
static void ricoh_mmc_fixup_r5c832(struct pci_dev *dev)
{
u8 write_enable;