2
0
mirror of https://github.com/edk2-porting/linux-next.git synced 2024-12-28 07:04:00 +08:00
linux-next/drivers/mmc/core/quirks.c
Ohad Ben-Cohen 14e7dc76f2 mmc: quirks: wl1271 is MMC_QUIRK_DISABLE_CD
The wl12xx device supports disconnecting the pull-up resistor on
CD/DAT[3] (pin 1) of the card.

Tell SDIO core to disconnect that resistor during card init,
since we don't need it at that point (and anyway all
hosts shall provide pull-up resistors on all data lines DAT[3:0]
as described in section 6 of the SD physical specification).

As a result, this may save some power, but it's also generally healthy
since it prevents both ends from pulling up that pin, which
results in undesirable asymmetric physical bus.

Signed-off-by: Ohad Ben-Cohen <ohad@wizery.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
2011-05-24 21:00:05 -04:00

89 lines
2.2 KiB
C

/*
* This file contains work-arounds for many known sdio hardware
* bugs.
*
* Copyright (c) 2011 Pierre Tardy <tardyp@gmail.com>
* Inspired from pci fixup code:
* Copyright (c) 1999 Martin Mares <mj@ucw.cz>
*
*/
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/mmc/card.h>
#include <linux/mod_devicetable.h>
/*
* The world is not perfect and supplies us with broken mmc/sdio devices.
* For at least a part of these bugs we need a work-around
*/
struct mmc_fixup {
u16 vendor, device; /* You can use SDIO_ANY_ID here of course */
void (*vendor_fixup)(struct mmc_card *card, int data);
int data;
};
/*
* This hook just adds a quirk unconditionnally
*/
static void __maybe_unused add_quirk(struct mmc_card *card, int data)
{
card->quirks |= data;
}
/*
* This hook just removes a quirk unconditionnally
*/
static void __maybe_unused remove_quirk(struct mmc_card *card, int data)
{
card->quirks &= ~data;
}
/*
* This hook just adds a quirk for all sdio devices
*/
static void add_quirk_for_sdio_devices(struct mmc_card *card, int data)
{
if (mmc_card_sdio(card))
card->quirks |= data;
}
#ifndef SDIO_VENDOR_ID_TI
#define SDIO_VENDOR_ID_TI 0x0097
#endif
#ifndef SDIO_DEVICE_ID_TI_WL1271
#define SDIO_DEVICE_ID_TI_WL1271 0x4076
#endif
static const struct mmc_fixup mmc_fixup_methods[] = {
/* by default sdio devices are considered CLK_GATING broken */
/* good cards will be whitelisted as they are tested */
{ SDIO_ANY_ID, SDIO_ANY_ID,
add_quirk_for_sdio_devices, MMC_QUIRK_BROKEN_CLK_GATING },
{ SDIO_VENDOR_ID_TI, SDIO_DEVICE_ID_TI_WL1271,
remove_quirk, MMC_QUIRK_BROKEN_CLK_GATING },
{ SDIO_VENDOR_ID_TI, SDIO_DEVICE_ID_TI_WL1271,
add_quirk, MMC_QUIRK_NONSTD_FUNC_IF },
{ SDIO_VENDOR_ID_TI, SDIO_DEVICE_ID_TI_WL1271,
add_quirk, MMC_QUIRK_DISABLE_CD },
{ 0 }
};
void mmc_fixup_device(struct mmc_card *card)
{
const struct mmc_fixup *f;
for (f = mmc_fixup_methods; f->vendor_fixup; f++) {
if ((f->vendor == card->cis.vendor
|| f->vendor == (u16) SDIO_ANY_ID) &&
(f->device == card->cis.device
|| f->device == (u16) SDIO_ANY_ID)) {
dev_dbg(&card->dev, "calling %pF\n", f->vendor_fixup);
f->vendor_fixup(card, f->data);
}
}
}
EXPORT_SYMBOL(mmc_fixup_device);