[PATCH 1/2] mmc: add MMC_QUIRK_DISABLE_CD

[PATCH 1/2] mmc: add MMC_QUIRK_DISABLE_CD

[Ohad Ben-Cohen]

006ebd5d introduced sdio_disable_cd(), which disconnects the pull-up
resistor on CD/DAT[3] (pin 1) of the card.

Make it possible to start using sdio_disable_cd() by introducing
MMC_QUIRK_DISABLE_CD.

Signed-off-by: Ohad Ben-Cohen <ohad@wizery.com>
---
Chris, I've posted this one before. Sending it again, this time with a follow-up patch that uses the new mmc quirks facility. thanks!

 drivers/mmc/core/sdio.c  |    2 +-
 include/linux/mmc/card.h |    6 ++++++
 2 files changed, 7 insertions(+), 1 deletions(-)

diff --git a/drivers/mmc/core/sdio.c b/drivers/mmc/core/sdio.c
index c3c2bd0..a5840c0 100644
--- a/drivers/mmc/core/sdio.c
+++ b/drivers/mmc/core/sdio.c
@@ -187,7 +187,7 @@ static int sdio_disable_cd(struct mmc_card *card)
 	int ret;
 	u8 ctrl;
 
-	if (!card->cccr.disable_cd)
+	if (!mmc_card_disable_cd(card))
 		return 0;
 
 	ret = mmc_io_rw_direct(card, 0, 0, SDIO_CCCR_IF, 0, &ctrl);
diff --git a/include/linux/mmc/card.h b/include/linux/mmc/card.h
index c7f1532..4e03be8 100644
--- a/include/linux/mmc/card.h
+++ b/include/linux/mmc/card.h
@@ -126,6 +126,7 @@ struct mmc_card {
 						/* (missing CIA registers) */
 #define MMC_QUIRK_BROKEN_CLK_GATING (1<<3)	/* clock gating the sdio bus will make card fail */
 #define MMC_QUIRK_NONSTD_FUNC_IF (1<<4)		/* SDIO card has nonstd function interfaces */
+#define MMC_QUIRK_DISABLE_CD	(1<<5)		/* disconnect CD/DAT[3] resistor */
 
 	unsigned int		erase_size;	/* erase size in sectors */
  	unsigned int		erase_shift;	/* if erase unit is power 2 */
@@ -181,6 +182,11 @@ static inline int mmc_blksz_for_byte_mode(const struct mmc_card *c)
 	return c->quirks & MMC_QUIRK_BLKSZ_FOR_BYTE_MODE;
 }
 
+static inline int mmc_card_disable_cd(const struct mmc_card *c)
+{
+	return c->quirks & MMC_QUIRK_DISABLE_CD;
+}
+
 static inline int mmc_card_nonstd_func_interface(const struct mmc_card *c)
 {
 	return c->quirks & MMC_QUIRK_NONSTD_FUNC_IF;
-- 
1.7.1

[PATCH 2/2] mmc: quirks: wl1271 is MMC_QUIRK_DISABLE_CD

[Ohad Ben-Cohen]

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>
---
 drivers/mmc/core/quirks.c |    2 ++
 1 files changed, 2 insertions(+), 0 deletions(-)

diff --git a/drivers/mmc/core/quirks.c b/drivers/mmc/core/quirks.c
index 1957398..a4c42ed 100644
--- a/drivers/mmc/core/quirks.c
+++ b/drivers/mmc/core/quirks.c
@@ -66,6 +66,8 @@ static const struct mmc_fixup mmc_fixup_methods[] = {
 		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 }
 };
 
-- 
1.7.1

Re: [PATCH 1/2] mmc: add MMC_QUIRK_DISABLE_CD

[Chris Ball]

Hi,

On Tue, Apr 05 2011, Ohad Ben-Cohen wrote:
> 006ebd5d introduced sdio_disable_cd(), which disconnects the pull-up
> resistor on CD/DAT[3] (pin 1) of the card.
>
> Make it possible to start using sdio_disable_cd() by introducing
> MMC_QUIRK_DISABLE_CD.
>
> Signed-off-by: Ohad Ben-Cohen <ohad@wizery.com>
> ---
> Chris, I've posted this one before. Sending it again, this time with a follow-up patch that uses the new mmc quirks facility. thanks!
>
>  drivers/mmc/core/sdio.c  |    2 +-
>  include/linux/mmc/card.h |    6 ++++++
>  2 files changed, 7 insertions(+), 1 deletions(-)
>
> diff --git a/drivers/mmc/core/sdio.c b/drivers/mmc/core/sdio.c
> index c3c2bd0..a5840c0 100644
> --- a/drivers/mmc/core/sdio.c
> +++ b/drivers/mmc/core/sdio.c
> @@ -187,7 +187,7 @@ static int sdio_disable_cd(struct mmc_card *card)
>  	int ret;
>  	u8 ctrl;
>  
> -	if (!card->cccr.disable_cd)
> +	if (!mmc_card_disable_cd(card))
>  		return 0;
>  
>  	ret = mmc_io_rw_direct(card, 0, 0, SDIO_CCCR_IF, 0, &ctrl);
> diff --git a/include/linux/mmc/card.h b/include/linux/mmc/card.h
> index c7f1532..4e03be8 100644
> --- a/include/linux/mmc/card.h
> +++ b/include/linux/mmc/card.h
> @@ -126,6 +126,7 @@ struct mmc_card {
>  						/* (missing CIA registers) */
>  #define MMC_QUIRK_BROKEN_CLK_GATING (1<<3)	/* clock gating the sdio bus will make card fail */
>  #define MMC_QUIRK_NONSTD_FUNC_IF (1<<4)		/* SDIO card has nonstd function interfaces */
> +#define MMC_QUIRK_DISABLE_CD	(1<<5)		/* disconnect CD/DAT[3] resistor */
>  
>  	unsigned int		erase_size;	/* erase size in sectors */
>   	unsigned int		erase_shift;	/* if erase unit is power 2 */
> @@ -181,6 +182,11 @@ static inline int mmc_blksz_for_byte_mode(const struct mmc_card *c)
>  	return c->quirks & MMC_QUIRK_BLKSZ_FOR_BYTE_MODE;
>  }
>  
> +static inline int mmc_card_disable_cd(const struct mmc_card *c)
> +{
> +	return c->quirks & MMC_QUIRK_DISABLE_CD;
> +}
> +
>  static inline int mmc_card_nonstd_func_interface(const struct mmc_card *c)
>  {
>  	return c->quirks & MMC_QUIRK_NONSTD_FUNC_IF;

Thanks, pushed to mmc-next for .40.

- Chris.
-- 
Chris Ball   <cjb@laptop.org>   <http://printf.net/>
One Laptop Per Child

Re: [PATCH 2/2] mmc: quirks: wl1271 is MMC_QUIRK_DISABLE_CD

[Chris Ball]

Hi,

On Tue, Apr 05 2011, Ohad Ben-Cohen wrote:
> 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>
> ---
>  drivers/mmc/core/quirks.c |    2 ++
>  1 files changed, 2 insertions(+), 0 deletions(-)
>
> diff --git a/drivers/mmc/core/quirks.c b/drivers/mmc/core/quirks.c
> index 1957398..a4c42ed 100644
> --- a/drivers/mmc/core/quirks.c
> +++ b/drivers/mmc/core/quirks.c
> @@ -66,6 +66,8 @@ static const struct mmc_fixup mmc_fixup_methods[] = {
>  		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 }
>  };

Thanks, pushed to mmc-next for .40.

- Chris.
-- 
Chris Ball   <cjb@laptop.org>   <http://printf.net/>
One Laptop Per Child