linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
* [PATCH v4] mmc: Make ID freq configurable
@ 2010-09-02 21:34 Hein_Tibosch
  2010-09-03  1:47 ` Chris Ball
                   ` (2 more replies)
  0 siblings, 3 replies; 13+ messages in thread
From: Hein_Tibosch @ 2010-09-02 21:34 UTC (permalink / raw)
  To: Andrew Morton
  Cc: Pierre Ossman, Chris Ball, Ben Nizette, Sascha Hauer,
	Adrian Hunter, linux-mmc, linux-kernel, Matt Fleming

In the latest releases of the mmc driver, the freq during initialization
is set to a fixed 400 Khz. This was reportedly too fast for several
users. As there doesn't seem to be an ideal frequency which-works-for-all,
Pierre suggested to let the driver try several frequencies.

This patch implements that idea. It will try mmc-initialization using
several frequencies from an array 400, 300, 200 and 100.
I submitted it earlier but it's now adapted to and tested with kernel
2.6.36-rc3.

In case SDIO is broken, it'll still try to detect SDMEM, also at different
freqs.

Signed-off-by: Hein Tibosch <hein_tibosch@yahoo.es>

---
diff -Nurp a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c
--- a/drivers/mmc/core/core.c	2010-08-29 23:36:04.000000000 +0800
+++ b/drivers/mmc/core/core.c	2010-09-03 04:28:52.000000000 +0800
@@ -907,12 +907,7 @@ static void mmc_power_up(struct mmc_host
 	 */
 	mmc_delay(10);

-	if (host->f_min > 400000) {
-		pr_warning("%s: Minimum clock frequency too high for "
-				"identification mode\n", mmc_hostname(host));
-		host->ios.clock = host->f_min;
-	} else
-		host->ios.clock = 400000;
+	host->ios.clock = host->f_init;

 	host->ios.power_mode = MMC_POWER_ON;
 	mmc_set_ios(host);
@@ -1404,6 +1399,8 @@ void mmc_rescan(struct work_struct *work
 	u32 ocr;
 	int err;
 	unsigned long flags;
+	int i;
+	unsigned freqs[] = { 400000, 300000, 200000, 100000 };

 	spin_lock_irqsave(&host->lock, flags);

@@ -1443,55 +1440,64 @@ void mmc_rescan(struct work_struct *work
 	if (host->ops->get_cd && host->ops->get_cd(host) == 0)
 		goto out;

-	mmc_claim_host(host);
+	for (i = 0; i < ARRAY_SIZE(freqs); i++) {
+		mmc_claim_host(host);

-	mmc_power_up(host);
-	sdio_reset(host);
-	mmc_go_idle(host);
+		if (freqs[i] >= host->f_min)
+			host->f_init = freqs[i];
+		else if (i && freqs[i-1] <= host->f_min)
+			goto out;
+		else
+			host->f_init = host->f_min;

-	mmc_send_if_cond(host, host->ocr_avail);
+		printk ("mmc_rescan: trying %u Hz\n", host->f_init);
+		mmc_power_up(host);
+		sdio_reset(host);
+		mmc_go_idle(host);

-	/*
-	 * First we search for SDIO...
-	 */
-	err = mmc_send_io_op_cond(host, 0, &ocr);
-	if (!err) {
-		if (mmc_attach_sdio(host, ocr)) {
-			mmc_claim_host(host);
-			/* try SDMEM (but not MMC) even if SDIO is broken */
-			if (mmc_send_app_op_cond(host, 0, &ocr))
-				goto out_fail;
+		mmc_send_if_cond(host, host->ocr_avail);
+
+		/*
+		 * First we search for SDIO...
+		 */
+		err = mmc_send_io_op_cond(host, 0, &ocr);
+		if (!err) {
+			if (mmc_attach_sdio(host, ocr)) {
+				mmc_claim_host(host);
+				/* try SDMEM (but not MMC) even if SDIO is broken */
+				if (mmc_send_app_op_cond(host, 0, &ocr))
+					goto out_fail;
+
+				if (mmc_attach_sd(host, ocr))
+					mmc_power_off(host);
+			}
+			goto out;
+		}

+		/*
+		 * ...then normal SD...
+		 */
+		err = mmc_send_app_op_cond(host, 0, &ocr);
+		if (!err) {
 			if (mmc_attach_sd(host, ocr))
 				mmc_power_off(host);
+			goto out;
 		}
-		goto out;
-	}

-	/*
-	 * ...then normal SD...
-	 */
-	err = mmc_send_app_op_cond(host, 0, &ocr);
-	if (!err) {
-		if (mmc_attach_sd(host, ocr))
-			mmc_power_off(host);
-		goto out;
-	}
-
-	/*
-	 * ...and finally MMC.
-	 */
-	err = mmc_send_op_cond(host, 0, &ocr);
-	if (!err) {
-		if (mmc_attach_mmc(host, ocr))
-			mmc_power_off(host);
-		goto out;
-	}
+		/*
+		 * ...and finally MMC.
+		 */
+		err = mmc_send_op_cond(host, 0, &ocr);
+		if (!err) {
+			if (mmc_attach_mmc(host, ocr))
+				mmc_power_off(host);
+			goto out;
+		}

 out_fail:
-	mmc_release_host(host);
-	mmc_power_off(host);
-
+		mmc_release_host(host);
+		mmc_power_off(host);
+	}
 out:
 	if (host->caps & MMC_CAP_NEEDS_POLL)
 		mmc_schedule_delayed_work(&host->detect, HZ);
diff -Nurp a/include/linux/mmc/host.h b/include/linux/mmc/host.h
--- a/include/linux/mmc/host.h	2010-08-29 23:36:04.000000000 +0800
+++ b/include/linux/mmc/host.h	2010-09-03 00:52:48.000000000 +0800
@@ -123,6 +123,7 @@ struct mmc_host {
 	const struct mmc_host_ops *ops;
 	unsigned int		f_min;
 	unsigned int		f_max;
+	unsigned int		f_init;
 	u32			ocr_avail;
 	struct notifier_block	pm_notify;

---


^ permalink raw reply	[flat|nested] 13+ messages in thread

* Re: [PATCH v4] mmc: Make ID freq configurable
  2010-09-02 21:34 [PATCH v4] mmc: Make ID freq configurable Hein_Tibosch
@ 2010-09-03  1:47 ` Chris Ball
  2010-09-03 23:25   ` Andrew Morton
  2010-09-05 20:14 ` Matt Fleming
  2010-12-02 11:16 ` [PATCH v4] " Sahitya Tummala
  2 siblings, 1 reply; 13+ messages in thread
From: Chris Ball @ 2010-09-03  1:47 UTC (permalink / raw)
  To: Hein_Tibosch
  Cc: Andrew Morton, Pierre Ossman, Ben Nizette, Sascha Hauer,
	Adrian Hunter, linux-mmc, linux-kernel, Matt Fleming

Hi Hein, thanks for resending this,

On Fri, Sep 03, 2010 at 05:34:53AM +0800, Hein_Tibosch wrote:
> In the latest releases of the mmc driver, the freq during initialization
> is set to a fixed 400 Khz. This was reportedly too fast for several
> users. As there doesn't seem to be an ideal frequency which-works-for-all,
> Pierre suggested to let the driver try several frequencies.
> 
> This patch implements that idea. It will try mmc-initialization using
> several frequencies from an array 400, 300, 200 and 100.
> I submitted it earlier but it's now adapted to and tested with kernel
> 2.6.36-rc3.
> 
> In case SDIO is broken, it'll still try to detect SDMEM, also at different
> freqs.
> 
> Signed-off-by: Hein Tibosch <hein_tibosch@yahoo.es>

Reviewed-and-Tested-by: Chris Ball <cjb@laptop.org>

I tested by modifying mmc_send_app_op_cond() to return timeouts for
various frequencies, and verified that the code correctly progresses
through the freqs[] table until reaching host->f_min, and can bring
up the card successfully on any of those retries.

In an earlier mail, you said:

> Here it tries 3 frequencies, which takes 290 ms:
> In a meanwhile it is doing other things, so not much time is wasted.

I decided to check this.  If my emulated failing of bringing up a card
at a given frequency is correct, 14ms per frequency attempt is spent in 
mdelay() rather than msleep().  I don't think this is a problem, though,
because you only take that hit if you have a card inserted that we're
unable to bring up at the default frequency -- the only alternative
would be to give up on the card.

If a host has no card inserted then we still try to detect a card on
all frequencies, but all of the paths in that case are msleep() rather
than mdelay(), so that's okay.

Two minor checkpatch fixes below:

> ---
> diff -Nurp a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c
> --- a/drivers/mmc/core/core.c	2010-08-29 23:36:04.000000000 +0800
> +++ b/drivers/mmc/core/core.c	2010-09-03 04:28:52.000000000 +0800
> @@ -907,12 +907,7 @@ static void mmc_power_up(struct mmc_host
>  	 */
>  	mmc_delay(10);
> 
> -	if (host->f_min > 400000) {
> -		pr_warning("%s: Minimum clock frequency too high for "
> -				"identification mode\n", mmc_hostname(host));
> -		host->ios.clock = host->f_min;
> -	} else
> -		host->ios.clock = 400000;
> +	host->ios.clock = host->f_init;
> 
>  	host->ios.power_mode = MMC_POWER_ON;
>  	mmc_set_ios(host);
> @@ -1404,6 +1399,8 @@ void mmc_rescan(struct work_struct *work
>  	u32 ocr;
>  	int err;
>  	unsigned long flags;
> +	int i;
> +	unsigned freqs[] = { 400000, 300000, 200000, 100000 };
> 
>  	spin_lock_irqsave(&host->lock, flags);
> 
> @@ -1443,55 +1440,64 @@ void mmc_rescan(struct work_struct *work
>  	if (host->ops->get_cd && host->ops->get_cd(host) == 0)
>  		goto out;
> 
> -	mmc_claim_host(host);
> +	for (i = 0; i < ARRAY_SIZE(freqs); i++) {
> +		mmc_claim_host(host);
> 
> -	mmc_power_up(host);
> -	sdio_reset(host);
> -	mmc_go_idle(host);
> +		if (freqs[i] >= host->f_min)
> +			host->f_init = freqs[i];
> +		else if (i && freqs[i-1] <= host->f_min)
> +			goto out;
> +		else
> +			host->f_init = host->f_min;
> 
> -	mmc_send_if_cond(host, host->ocr_avail);
> +		printk ("mmc_rescan: trying %u Hz\n", host->f_init);

Need a loglevel here, and an mmc_hostname.  Something like:

                pr_info("%s: %s: trying to init card at %u Hz\n",
                        mmc_hostname(host), __func__, host->f_init);

> +		mmc_power_up(host);
> +		sdio_reset(host);
> +		mmc_go_idle(host);
> 
> -	/*
> -	 * First we search for SDIO...
> -	 */
> -	err = mmc_send_io_op_cond(host, 0, &ocr);
> -	if (!err) {
> -		if (mmc_attach_sdio(host, ocr)) {
> -			mmc_claim_host(host);
> -			/* try SDMEM (but not MMC) even if SDIO is broken */
> -			if (mmc_send_app_op_cond(host, 0, &ocr))
> -				goto out_fail;
> +		mmc_send_if_cond(host, host->ocr_avail);
> +
> +		/*
> +		 * First we search for SDIO...
> +		 */
> +		err = mmc_send_io_op_cond(host, 0, &ocr);
> +		if (!err) {
> +			if (mmc_attach_sdio(host, ocr)) {
> +				mmc_claim_host(host);
> +				/* try SDMEM (but not MMC) even if SDIO is broken */

This breaks 80-chars, so:

                                /*
                                 * Try SDMEM (but not MMC) even if SDIO
                                 * is broken.
                                 */

> +				if (mmc_send_app_op_cond(host, 0, &ocr))
> +					goto out_fail;
> +
> +				if (mmc_attach_sd(host, ocr))
> +					mmc_power_off(host);
> +			}
> +			goto out;
> +		}
> 
> +		/*
> +		 * ...then normal SD...
> +		 */
> +		err = mmc_send_app_op_cond(host, 0, &ocr);
> +		if (!err) {
>  			if (mmc_attach_sd(host, ocr))
>  				mmc_power_off(host);
> +			goto out;
>  		}
> -		goto out;
> -	}
> 
> -	/*
> -	 * ...then normal SD...
> -	 */
> -	err = mmc_send_app_op_cond(host, 0, &ocr);
> -	if (!err) {
> -		if (mmc_attach_sd(host, ocr))
> -			mmc_power_off(host);
> -		goto out;
> -	}
> -
> -	/*
> -	 * ...and finally MMC.
> -	 */
> -	err = mmc_send_op_cond(host, 0, &ocr);
> -	if (!err) {
> -		if (mmc_attach_mmc(host, ocr))
> -			mmc_power_off(host);
> -		goto out;
> -	}
> +		/*
> +		 * ...and finally MMC.
> +		 */
> +		err = mmc_send_op_cond(host, 0, &ocr);
> +		if (!err) {
> +			if (mmc_attach_mmc(host, ocr))
> +				mmc_power_off(host);
> +			goto out;
> +		}
> 
>  out_fail:
> -	mmc_release_host(host);
> -	mmc_power_off(host);
> -
> +		mmc_release_host(host);
> +		mmc_power_off(host);
> +	}
>  out:
>  	if (host->caps & MMC_CAP_NEEDS_POLL)
>  		mmc_schedule_delayed_work(&host->detect, HZ);
> diff -Nurp a/include/linux/mmc/host.h b/include/linux/mmc/host.h
> --- a/include/linux/mmc/host.h	2010-08-29 23:36:04.000000000 +0800
> +++ b/include/linux/mmc/host.h	2010-09-03 00:52:48.000000000 +0800
> @@ -123,6 +123,7 @@ struct mmc_host {
>  	const struct mmc_host_ops *ops;
>  	unsigned int		f_min;
>  	unsigned int		f_max;
> +	unsigned int		f_init;
>  	u32			ocr_avail;
>  	struct notifier_block	pm_notify;
> 
> ---

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

^ permalink raw reply	[flat|nested] 13+ messages in thread

* Re: [PATCH v4] mmc: Make ID freq configurable
  2010-09-03  1:47 ` Chris Ball
@ 2010-09-03 23:25   ` Andrew Morton
  0 siblings, 0 replies; 13+ messages in thread
From: Andrew Morton @ 2010-09-03 23:25 UTC (permalink / raw)
  To: Chris Ball
  Cc: Hein_Tibosch, Pierre Ossman, Ben Nizette, Sascha Hauer,
	Adrian Hunter, linux-mmc, linux-kernel, Matt Fleming

On Fri, 3 Sep 2010 02:47:57 +0100
Chris Ball <cjb@laptop.org> wrote:

> > -	mmc_send_if_cond(host, host->ocr_avail);
> > +		printk ("mmc_rescan: trying %u Hz\n", host->f_init);
> 
> Need a loglevel here, and an mmc_hostname.  Something like:
> 
>                 pr_info("%s: %s: trying to init card at %u Hz\n",
>                         mmc_hostname(host), __func__, host->f_init);
> 
> > +		mmc_power_up(host);
> > +		sdio_reset(host);
> > +		mmc_go_idle(host);
> > 
> > -	/*
> > -	 * First we search for SDIO...
> > -	 */
> > -	err = mmc_send_io_op_cond(host, 0, &ocr);
> > -	if (!err) {
> > -		if (mmc_attach_sdio(host, ocr)) {
> > -			mmc_claim_host(host);
> > -			/* try SDMEM (but not MMC) even if SDIO is broken */
> > -			if (mmc_send_app_op_cond(host, 0, &ocr))
> > -				goto out_fail;
> > +		mmc_send_if_cond(host, host->ocr_avail);
> > +
> > +		/*
> > +		 * First we search for SDIO...
> > +		 */
> > +		err = mmc_send_io_op_cond(host, 0, &ocr);
> > +		if (!err) {
> > +			if (mmc_attach_sdio(host, ocr)) {
> > +				mmc_claim_host(host);
> > +				/* try SDMEM (but not MMC) even if SDIO is broken */
> 
> This breaks 80-chars, so:
> 
>                                 /*
>                                  * Try SDMEM (but not MMC) even if SDIO
>                                  * is broken.
>                                  */

yup.

--- a/drivers/mmc/core/core.c~mmc-make-id-freq-configurable-checkpatch-fixes
+++ a/drivers/mmc/core/core.c
@@ -1450,7 +1450,9 @@ void mmc_rescan(struct work_struct *work
 		else
 			host->f_init = host->f_min;
 
-		printk ("mmc_rescan: trying %u Hz\n", host->f_init);
+		pr_info("%s: %s: trying to init card at %u Hz\n",
+			mmc_hostname(host), __func__, host->f_init);
+
 		mmc_power_up(host);
 		sdio_reset(host);
 		mmc_go_idle(host);
@@ -1464,7 +1466,10 @@ void mmc_rescan(struct work_struct *work
 		if (!err) {
 			if (mmc_attach_sdio(host, ocr)) {
 				mmc_claim_host(host);
-				/* try SDMEM (but not MMC) even if SDIO is broken */
+				/*
+				 * Try SDMEM (but not MMC) even if SDIO is
+				 * broken.
+				 */
 				if (mmc_send_app_op_cond(host, 0, &ocr))
 					goto out_fail;
 
diff -puN include/linux/mmc/host.h~mmc-make-id-freq-configurable-checkpatch-fixes include/linux/mmc/host.h
_


^ permalink raw reply	[flat|nested] 13+ messages in thread

* Re: [PATCH v4] mmc: Make ID freq configurable
  2010-09-02 21:34 [PATCH v4] mmc: Make ID freq configurable Hein_Tibosch
  2010-09-03  1:47 ` Chris Ball
@ 2010-09-05 20:14 ` Matt Fleming
  2010-09-05 20:43   ` Chris Ball
  2010-12-02 11:16 ` [PATCH v4] " Sahitya Tummala
  2 siblings, 1 reply; 13+ messages in thread
From: Matt Fleming @ 2010-09-05 20:14 UTC (permalink / raw)
  To: Hein_Tibosch
  Cc: Andrew Morton, Pierre Ossman, Chris Ball, Ben Nizette,
	Sascha Hauer, Adrian Hunter, linux-mmc, linux-kernel

On Fri, Sep 03, 2010 at 05:34:53AM +0800, Hein_Tibosch wrote:
> In the latest releases of the mmc driver, the freq during initialization
> is set to a fixed 400 Khz. This was reportedly too fast for several
> users. As there doesn't seem to be an ideal frequency which-works-for-all,
> Pierre suggested to let the driver try several frequencies.
> 
> This patch implements that idea. It will try mmc-initialization using
> several frequencies from an array 400, 300, 200 and 100.
> I submitted it earlier but it's now adapted to and tested with kernel
> 2.6.36-rc3.
> 
> In case SDIO is broken, it'll still try to detect SDMEM, also at different
> freqs.
> 
> Signed-off-by: Hein Tibosch <hein_tibosch@yahoo.es>
> 
> ---
> diff -Nurp a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c
> --- a/drivers/mmc/core/core.c	2010-08-29 23:36:04.000000000 +0800
> +++ b/drivers/mmc/core/core.c	2010-09-03 04:28:52.000000000 +0800
> @@ -907,12 +907,7 @@ static void mmc_power_up(struct mmc_host
>  	 */
>  	mmc_delay(10);
> 
> -	if (host->f_min > 400000) {
> -		pr_warning("%s: Minimum clock frequency too high for "
> -				"identification mode\n", mmc_hostname(host));
> -		host->ios.clock = host->f_min;
> -	} else
> -		host->ios.clock = 400000;
> +	host->ios.clock = host->f_init;
> 
>  	host->ios.power_mode = MMC_POWER_ON;
>  	mmc_set_ios(host);
> @@ -1404,6 +1399,8 @@ void mmc_rescan(struct work_struct *work
>  	u32 ocr;
>  	int err;
>  	unsigned long flags;
> +	int i;
> +	unsigned freqs[] = { 400000, 300000, 200000, 100000 };
> 
>  	spin_lock_irqsave(&host->lock, flags);
> 
> @@ -1443,55 +1440,64 @@ void mmc_rescan(struct work_struct *work
>  	if (host->ops->get_cd && host->ops->get_cd(host) == 0)
>  		goto out;
> 
> -	mmc_claim_host(host);
> +	for (i = 0; i < ARRAY_SIZE(freqs); i++) {
> +		mmc_claim_host(host);
> 
> -	mmc_power_up(host);
> -	sdio_reset(host);
> -	mmc_go_idle(host);
> +		if (freqs[i] >= host->f_min)
> +			host->f_init = freqs[i];
> +		else if (i && freqs[i-1] <= host->f_min)
> +			goto out;

The label 'out' does not release the claim on the host.

> +		else
> +			host->f_init = host->f_min;
> 
> -	mmc_send_if_cond(host, host->ocr_avail);
> +		printk ("mmc_rescan: trying %u Hz\n", host->f_init);
> +		mmc_power_up(host);
> +		sdio_reset(host);
> +		mmc_go_idle(host);
> 
> -	/*
> -	 * First we search for SDIO...
> -	 */
> -	err = mmc_send_io_op_cond(host, 0, &ocr);
> -	if (!err) {
> -		if (mmc_attach_sdio(host, ocr)) {
> -			mmc_claim_host(host);
> -			/* try SDMEM (but not MMC) even if SDIO is broken */
> -			if (mmc_send_app_op_cond(host, 0, &ocr))
> -				goto out_fail;
> +		mmc_send_if_cond(host, host->ocr_avail);
> +
> +		/*
> +		 * First we search for SDIO...
> +		 */
> +		err = mmc_send_io_op_cond(host, 0, &ocr);
> +		if (!err) {
> +			if (mmc_attach_sdio(host, ocr)) {
> +				mmc_claim_host(host);
> +				/* try SDMEM (but not MMC) even if SDIO is broken */
> +				if (mmc_send_app_op_cond(host, 0, &ocr))
> +					goto out_fail;
> +
> +				if (mmc_attach_sd(host, ocr))
> +					mmc_power_off(host);
> +			}
> +			goto out;
> +		}
> 
> +		/*
> +		 * ...then normal SD...
> +		 */
> +		err = mmc_send_app_op_cond(host, 0, &ocr);
> +		if (!err) {
>  			if (mmc_attach_sd(host, ocr))
>  				mmc_power_off(host);
> +			goto out;

Same problem here.

>  		}
> -		goto out;
> -	}
> 
> -	/*
> -	 * ...then normal SD...
> -	 */
> -	err = mmc_send_app_op_cond(host, 0, &ocr);
> -	if (!err) {
> -		if (mmc_attach_sd(host, ocr))
> -			mmc_power_off(host);
> -		goto out;
> -	}
> -
> -	/*
> -	 * ...and finally MMC.
> -	 */
> -	err = mmc_send_op_cond(host, 0, &ocr);
> -	if (!err) {
> -		if (mmc_attach_mmc(host, ocr))
> -			mmc_power_off(host);
> -		goto out;
> -	}
> +		/*
> +		 * ...and finally MMC.
> +		 */
> +		err = mmc_send_op_cond(host, 0, &ocr);
> +		if (!err) {
> +			if (mmc_attach_mmc(host, ocr))
> +				mmc_power_off(host);
> +			goto out;
> +		}

And here.

^ permalink raw reply	[flat|nested] 13+ messages in thread

* Re: [PATCH v4] mmc: Make ID freq configurable
  2010-09-05 20:14 ` Matt Fleming
@ 2010-09-05 20:43   ` Chris Ball
  2010-09-05 21:22     ` Matt Fleming
  0 siblings, 1 reply; 13+ messages in thread
From: Chris Ball @ 2010-09-05 20:43 UTC (permalink / raw)
  To: Matt Fleming
  Cc: Hein_Tibosch, Andrew Morton, Pierre Ossman, Chris Ball,
	Ben Nizette, Sascha Hauer, Adrian Hunter, linux-mmc, linux-kernel

Hi Matt,

On Sun, Sep 05, 2010 at 09:14:48PM +0100, Matt Fleming wrote:
> On Fri, Sep 03, 2010 at 05:34:53AM +0800, Hein_Tibosch wrote:
> > In the latest releases of the mmc driver, the freq during initialization
> > is set to a fixed 400 Khz. This was reportedly too fast for several
> > users. As there doesn't seem to be an ideal frequency which-works-for-all,
> > Pierre suggested to let the driver try several frequencies.
> > 
> > This patch implements that idea. It will try mmc-initialization using
> > several frequencies from an array 400, 300, 200 and 100.
> > I submitted it earlier but it's now adapted to and tested with kernel
> > 2.6.36-rc3.
> > 
> > In case SDIO is broken, it'll still try to detect SDMEM, also at different
> > freqs.
> > 
> > Signed-off-by: Hein Tibosch <hein_tibosch@yahoo.es>
> > 
> > ---
> > diff -Nurp a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c
> > --- a/drivers/mmc/core/core.c	2010-08-29 23:36:04.000000000 +0800
> > +++ b/drivers/mmc/core/core.c	2010-09-03 04:28:52.000000000 +0800
> > @@ -907,12 +907,7 @@ static void mmc_power_up(struct mmc_host
> >  	 */
> >  	mmc_delay(10);
> > 
> > -	if (host->f_min > 400000) {
> > -		pr_warning("%s: Minimum clock frequency too high for "
> > -				"identification mode\n", mmc_hostname(host));
> > -		host->ios.clock = host->f_min;
> > -	} else
> > -		host->ios.clock = 400000;
> > +	host->ios.clock = host->f_init;
> > 
> >  	host->ios.power_mode = MMC_POWER_ON;
> >  	mmc_set_ios(host);
> > @@ -1404,6 +1399,8 @@ void mmc_rescan(struct work_struct *work
> >  	u32 ocr;
> >  	int err;
> >  	unsigned long flags;
> > +	int i;
> > +	unsigned freqs[] = { 400000, 300000, 200000, 100000 };
> > 
> >  	spin_lock_irqsave(&host->lock, flags);
> > 
> > @@ -1443,55 +1440,64 @@ void mmc_rescan(struct work_struct *work
> >  	if (host->ops->get_cd && host->ops->get_cd(host) == 0)
> >  		goto out;
> > 
> > -	mmc_claim_host(host);
> > +	for (i = 0; i < ARRAY_SIZE(freqs); i++) {
> > +		mmc_claim_host(host);
> > 
> > -	mmc_power_up(host);
> > -	sdio_reset(host);
> > -	mmc_go_idle(host);
> > +		if (freqs[i] >= host->f_min)
> > +			host->f_init = freqs[i];
> > +		else if (i && freqs[i-1] <= host->f_min)
> > +			goto out;
> 
> The label 'out' does not release the claim on the host.

Thanks for catching that.

> > +		else
> > +			host->f_init = host->f_min;
> > 
> > -	mmc_send_if_cond(host, host->ocr_avail);
> > +		printk ("mmc_rescan: trying %u Hz\n", host->f_init);
> > +		mmc_power_up(host);
> > +		sdio_reset(host);
> > +		mmc_go_idle(host);
> > 
> > -	/*
> > -	 * First we search for SDIO...
> > -	 */
> > -	err = mmc_send_io_op_cond(host, 0, &ocr);
> > -	if (!err) {
> > -		if (mmc_attach_sdio(host, ocr)) {
> > -			mmc_claim_host(host);
> > -			/* try SDMEM (but not MMC) even if SDIO is broken */
> > -			if (mmc_send_app_op_cond(host, 0, &ocr))
> > -				goto out_fail;
> > +		mmc_send_if_cond(host, host->ocr_avail);
> > +
> > +		/*
> > +		 * First we search for SDIO...
> > +		 */
> > +		err = mmc_send_io_op_cond(host, 0, &ocr);
> > +		if (!err) {
> > +			if (mmc_attach_sdio(host, ocr)) {
> > +				mmc_claim_host(host);
> > +				/* try SDMEM (but not MMC) even if SDIO is broken */
> > +				if (mmc_send_app_op_cond(host, 0, &ocr))
> > +					goto out_fail;
> > +
> > +				if (mmc_attach_sd(host, ocr))
> > +					mmc_power_off(host);
> > +			}
> > +			goto out;
> > +		}
> > 
> > +		/*
> > +		 * ...then normal SD...
> > +		 */
> > +		err = mmc_send_app_op_cond(host, 0, &ocr);
> > +		if (!err) {
> >  			if (mmc_attach_sd(host, ocr))
> >  				mmc_power_off(host);
> > +			goto out;
> 
> Same problem here.
> 
> >  		}
> > -		goto out;
> > -	}
> > 
> > -	/*
> > -	 * ...then normal SD...
> > -	 */
> > -	err = mmc_send_app_op_cond(host, 0, &ocr);
> > -	if (!err) {
> > -		if (mmc_attach_sd(host, ocr))
> > -			mmc_power_off(host);
> > -		goto out;
> > -	}
> > -
> > -	/*
> > -	 * ...and finally MMC.
> > -	 */
> > -	err = mmc_send_op_cond(host, 0, &ocr);
> > -	if (!err) {
> > -		if (mmc_attach_mmc(host, ocr))
> > -			mmc_power_off(host);
> > -		goto out;
> > -	}
> > +		/*
> > +		 * ...and finally MMC.
> > +		 */
> > +		err = mmc_send_op_cond(host, 0, &ocr);
> > +		if (!err) {
> > +			if (mmc_attach_mmc(host, ocr))
> > +				mmc_power_off(host);
> > +			goto out;
> > +		}
> 
> And here.

Actually, mmc_attach_{sd,mmc}() both do release the host as part of
their failure case, so I don't think there's a problem with these two.

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

^ permalink raw reply	[flat|nested] 13+ messages in thread

* Re: [PATCH v4] mmc: Make ID freq configurable
  2010-09-05 20:43   ` Chris Ball
@ 2010-09-05 21:22     ` Matt Fleming
  2010-09-06  1:37       ` [PATCH v5] " Hein_Tibosch
  0 siblings, 1 reply; 13+ messages in thread
From: Matt Fleming @ 2010-09-05 21:22 UTC (permalink / raw)
  To: Chris Ball
  Cc: Hein_Tibosch, Andrew Morton, Pierre Ossman, Ben Nizette,
	Sascha Hauer, Adrian Hunter, linux-mmc, linux-kernel

On Sun, Sep 05, 2010 at 09:43:36PM +0100, Chris Ball wrote:
> 
> Actually, mmc_attach_{sd,mmc}() both do release the host as part of
> their failure case, so I don't think there's a problem with these two.

Ah, yep you're right, I missed that.

^ permalink raw reply	[flat|nested] 13+ messages in thread

* [PATCH v5] mmc: Make ID freq configurable
  2010-09-05 21:22     ` Matt Fleming
@ 2010-09-06  1:37       ` Hein_Tibosch
  0 siblings, 0 replies; 13+ messages in thread
From: Hein_Tibosch @ 2010-09-06  1:37 UTC (permalink / raw)
  To: Andrew Morton
  Cc: Chris Ball, Matt Fleming, Pierre Ossman, Ben Nizette,
	Sascha Hauer, Adrian Hunter, linux-mmc, linux-kernel

Matt, Chris,

Thanks both for reviewing.

I never noticed that the host wasn't released because my f_min was low enough
so that all frequencies would be tried. But yes, you're both right.

Before somebody else makes the remark: "unsigned freqs[]" can be declared as
const.

Below, I changed the order of the if/else/else, and whenever no more frequencies
can be tried, it will release the host before branching out.

Hein Tibosch

---

mmc-make-id-freq-configurable.patch (v5)

In the latest releases of the mmc driver, the freq during initialization
is set to a fixed 400 Khz. This was reportedly too fast for several
users. As there doesn't seem to be an ideal frequency which-works-for-all,
Pierre suggested to let the driver try several frequencies.

This patch implements that idea. It will try mmc-initialization using
several frequencies from an array 400, 300, 200 and 100.
I submitted it earlier but it's now adapted to and tested with kernel
2.6.36-rc3.

In case SDIO is detected but turns out broken, it'll still try to detect
SDMEM, also at different freqs.


Signed-off-by: Hein Tibosch <hein_tibosch@yahoo.es>
Reviewed-and-Tested-by: Chris Ball <cjb@laptop.org>

---
diff -Nurp a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c
--- a/drivers/mmc/core/core.c	2010-08-29 23:36:04.000000000 +0800
+++ b/drivers/mmc/core/core.c	2010-09-06 09:16:35.000000000 +0800
@@ -907,12 +907,7 @@ static void mmc_power_up(struct mmc_host
 	 */
 	mmc_delay(10);

-	if (host->f_min > 400000) {
-		pr_warning("%s: Minimum clock frequency too high for "
-				"identification mode\n", mmc_hostname(host));
-		host->ios.clock = host->f_min;
-	} else
-		host->ios.clock = 400000;
+	host->ios.clock = host->f_init;

 	host->ios.power_mode = MMC_POWER_ON;
 	mmc_set_ios(host);
@@ -1404,6 +1399,8 @@ void mmc_rescan(struct work_struct *work
 	u32 ocr;
 	int err;
 	unsigned long flags;
+	int i;
+	const unsigned freqs[] = { 400000, 300000, 200000, 100000 };

 	spin_lock_irqsave(&host->lock, flags);

@@ -1443,55 +1440,70 @@ void mmc_rescan(struct work_struct *work
 	if (host->ops->get_cd && host->ops->get_cd(host) == 0)
 		goto out;

-	mmc_claim_host(host);
+	for (i = 0; i < ARRAY_SIZE(freqs); i++) {
+		mmc_claim_host(host);

-	mmc_power_up(host);
-	sdio_reset(host);
-	mmc_go_idle(host);
+		if (freqs[i] >= host->f_min)
+			host->f_init = freqs[i];
+		else if (!i || freqs[i-1] > host->f_min)
+			host->f_init = host->f_min;
+		else {
+			mmc_release_host(host);
+			goto out;
+		}
+		pr_info("%s: %s: trying to init card at %u Hz\n",
+			mmc_hostname(host), __func__, host->f_init);

-	mmc_send_if_cond(host, host->ocr_avail);
+		mmc_power_up(host);
+		sdio_reset(host);
+		mmc_go_idle(host);

-	/*
-	 * First we search for SDIO...
-	 */
-	err = mmc_send_io_op_cond(host, 0, &ocr);
-	if (!err) {
-		if (mmc_attach_sdio(host, ocr)) {
-			mmc_claim_host(host);
-			/* try SDMEM (but not MMC) even if SDIO is broken */
-			if (mmc_send_app_op_cond(host, 0, &ocr))
-				goto out_fail;
+		mmc_send_if_cond(host, host->ocr_avail);
+
+		/*
+		 * First we search for SDIO...
+		 */
+		err = mmc_send_io_op_cond(host, 0, &ocr);
+		if (!err) {
+			if (mmc_attach_sdio(host, ocr)) {
+				mmc_claim_host(host);
+				/*
+				 * Try SDMEM (but not MMC) even if SDIO
+				 * is broken.
+				*/
+				if (mmc_send_app_op_cond(host, 0, &ocr))
+					goto out_fail;
+
+				if (mmc_attach_sd(host, ocr))
+					mmc_power_off(host);
+			}
+			goto out;
+		}

+		/*
+		 * ...then normal SD...
+		 */
+		err = mmc_send_app_op_cond(host, 0, &ocr);
+		if (!err) {
 			if (mmc_attach_sd(host, ocr))
 				mmc_power_off(host);
+			goto out;
 		}
-		goto out;
-	}
-
-	/*
-	 * ...then normal SD...
-	 */
-	err = mmc_send_app_op_cond(host, 0, &ocr);
-	if (!err) {
-		if (mmc_attach_sd(host, ocr))
-			mmc_power_off(host);
-		goto out;
-	}

-	/*
-	 * ...and finally MMC.
-	 */
-	err = mmc_send_op_cond(host, 0, &ocr);
-	if (!err) {
-		if (mmc_attach_mmc(host, ocr))
-			mmc_power_off(host);
-		goto out;
-	}
+		/*
+		 * ...and finally MMC.
+		 */
+		err = mmc_send_op_cond(host, 0, &ocr);
+		if (!err) {
+			if (mmc_attach_mmc(host, ocr))
+				mmc_power_off(host);
+			goto out;
+		}

 out_fail:
-	mmc_release_host(host);
-	mmc_power_off(host);
-
+		mmc_release_host(host);
+		mmc_power_off(host);
+	}
 out:
 	if (host->caps & MMC_CAP_NEEDS_POLL)
 		mmc_schedule_delayed_work(&host->detect, HZ);
diff -Nurp a/include/linux/mmc/host.h b/include/linux/mmc/host.h
--- a/include/linux/mmc/host.h	2010-08-29 23:36:04.000000000 +0800
+++ b/include/linux/mmc/host.h	2010-09-03 05:16:21.000000000 +0800
@@ -123,6 +123,7 @@ struct mmc_host {
 	const struct mmc_host_ops *ops;
 	unsigned int		f_min;
 	unsigned int		f_max;
+	unsigned int		f_init;
 	u32			ocr_avail;
 	struct notifier_block	pm_notify;

--



^ permalink raw reply	[flat|nested] 13+ messages in thread

* Re: [PATCH v4] mmc: Make ID freq configurable
  2010-09-02 21:34 [PATCH v4] mmc: Make ID freq configurable Hein_Tibosch
  2010-09-03  1:47 ` Chris Ball
  2010-09-05 20:14 ` Matt Fleming
@ 2010-12-02 11:16 ` Sahitya Tummala
  2010-12-02 21:21   ` Hein_Tibosch
  2 siblings, 1 reply; 13+ messages in thread
From: Sahitya Tummala @ 2010-12-02 11:16 UTC (permalink / raw)
  To: Hein_Tibosch
  Cc: Andrew Morton, Pierre Ossman, Chris Ball, Ben Nizette,
	Sascha Hauer, Adrian Hunter, linux-mmc, linux-kernel,
	Matt Fleming

Hi Hein Tibosch,

On Fri, 2010-09-03 at 05:34 +0800, Hein_Tibosch wrote:
> In the latest releases of the mmc driver, the freq during initialization
> is set to a fixed 400 Khz. This was reportedly too fast for several
> users. As there doesn't seem to be an ideal frequency which-works-for-all,
> Pierre suggested to let the driver try several frequencies.
> 
> This patch implements that idea. It will try mmc-initialization using
> several frequencies from an array 400, 300, 200 and 100.
> I submitted it earlier but it's now adapted to and tested with kernel
> 2.6.36-rc3.
> 
> In case SDIO is broken, it'll still try to detect SDMEM, also at different
> freqs.
> 
> Signed-off-by: Hein Tibosch <hein_tibosch@yahoo.es>
> 
> ---
> diff -Nurp a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c
> --- a/drivers/mmc/core/core.c	2010-08-29 23:36:04.000000000 +0800
> +++ b/drivers/mmc/core/core.c	2010-09-03 04:28:52.000000000 +0800
> @@ -907,12 +907,7 @@ static void mmc_power_up(struct mmc_host
>  	 */
>  	mmc_delay(10);
> 
> -	if (host->f_min > 400000) {
> -		pr_warning("%s: Minimum clock frequency too high for "
> -				"identification mode\n", mmc_hostname(host));
> -		host->ios.clock = host->f_min;
> -	} else
> -		host->ios.clock = 400000;
> +	host->ios.clock = host->f_init;
> 
>  	host->ios.power_mode = MMC_POWER_ON;
>  	mmc_set_ios(host);
> @@ -1404,6 +1399,8 @@ void mmc_rescan(struct work_struct *work
>  	u32 ocr;
>  	int err;
>  	unsigned long flags;
> +	int i;
> +	unsigned freqs[] = { 400000, 300000, 200000, 100000 };
> 
>  	spin_lock_irqsave(&host->lock, flags);
> 
> @@ -1443,55 +1440,64 @@ void mmc_rescan(struct work_struct *work
>  	if (host->ops->get_cd && host->ops->get_cd(host) == 0)
>  		goto out;
> 
> -	mmc_claim_host(host);
> +	for (i = 0; i < ARRAY_SIZE(freqs); i++) {
> +		mmc_claim_host(host);
> 
> -	mmc_power_up(host);
> -	sdio_reset(host);
> -	mmc_go_idle(host);
> +		if (freqs[i] >= host->f_min)
> +			host->f_init = freqs[i];
> +		else if (i && freqs[i-1] <= host->f_min)
> +			goto out;
> +		else
> +			host->f_init = host->f_min;
> 
> -	mmc_send_if_cond(host, host->ocr_avail);
> +		printk ("mmc_rescan: trying %u Hz\n", host->f_init);
> +		mmc_power_up(host);
> +		sdio_reset(host);
> +		mmc_go_idle(host);
> 
> -	/*
> -	 * First we search for SDIO...
> -	 */
> -	err = mmc_send_io_op_cond(host, 0, &ocr);
> -	if (!err) {
> -		if (mmc_attach_sdio(host, ocr)) {
> -			mmc_claim_host(host);
> -			/* try SDMEM (but not MMC) even if SDIO is broken */
> -			if (mmc_send_app_op_cond(host, 0, &ocr))
> -				goto out_fail;
> +		mmc_send_if_cond(host, host->ocr_avail);
> +
> +		/*
> +		 * First we search for SDIO...
> +		 */
> +		err = mmc_send_io_op_cond(host, 0, &ocr);
> +		if (!err) {
> +			if (mmc_attach_sdio(host, ocr)) {
> +				mmc_claim_host(host);
> +				/* try SDMEM (but not MMC) even if SDIO is broken */
> +				if (mmc_send_app_op_cond(host, 0, &ocr))

In case of SDIO error, mmc_power_off() is getting called as part of
mmc_detach_bus().  Shouldn't we power up the host before checking for
SDMEM? Any comments?

> +					goto out_fail;
> +
> +				if (mmc_attach_sd(host, ocr))
> +					mmc_power_off(host);
> +			}
> +			goto out;
> +		}

Thanks,
Sahitya.
--
Sent by a consultant of the Qualcomm Innovation Center, Inc.
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora
Forum.


^ permalink raw reply	[flat|nested] 13+ messages in thread

* Re: [PATCH v4] mmc: Make ID freq configurable
  2010-12-02 11:16 ` [PATCH v4] " Sahitya Tummala
@ 2010-12-02 21:21   ` Hein_Tibosch
  2010-12-02 22:38     ` Michal Miroslaw
  0 siblings, 1 reply; 13+ messages in thread
From: Hein_Tibosch @ 2010-12-02 21:21 UTC (permalink / raw)
  To: Sahitya Tummala, Michal Miroslaw
  Cc: Andrew Morton, Pierre Ossman, Chris Ball, Ben Nizette,
	Sascha Hauer, Adrian Hunter, linux-mmc, linux-kernel,
	Matt Fleming

Hi Sahitya,

On 2-12-2010 19:16, Sahitya Tummala wrote:
> Hi Hein Tibosch,
>
> On Fri, 2010-09-03 at 05:34 +0800, Hein_Tibosch wrote:
>> In the latest releases of the mmc driver, the freq during initialization
>> is set to a fixed 400 Khz. This was reportedly too fast for several
>> users. As there doesn't seem to be an ideal frequency which-works-for-all,
>> Pierre suggested to let the driver try several frequencies.
>> <cut>
>> +		/*
>> +		 * First we search for SDIO...
>> +		 */
>> +		err = mmc_send_io_op_cond(host, 0, &ocr);
>> +		if (!err) {
>> +			if (mmc_attach_sdio(host, ocr)) {
>> +				mmc_claim_host(host);
>> +				/* try SDMEM (but not MMC) even if SDIO is broken */
>> +				if (mmc_send_app_op_cond(host, 0, &ocr))
> In case of SDIO error, mmc_power_off() is getting called as part of
> mmc_detach_bus().  Shouldn't we power up the host before checking for
> SDMEM? Any comments?
>
I think you should ask Michal Miroslaw, as he wrote the patch for the
SD-combo (IO + mem)*

But yes, in case of a failure, mmc_attach_sdio() will call mmc_detach_bus()
which in turn will call mmc_power_off()

And so it should be mmc_power_up() again before trying to detect SD memory.


Hein Tibosch

* http://permalink.gmane.org/gmane.linux.kernel.mmc/2052

^ permalink raw reply	[flat|nested] 13+ messages in thread

* Re: [PATCH v4] mmc: Make ID freq configurable
  2010-12-02 21:21   ` Hein_Tibosch
@ 2010-12-02 22:38     ` Michal Miroslaw
  2010-12-03  5:05       ` stummala
  2010-12-17  1:09       ` Chris Ball
  0 siblings, 2 replies; 13+ messages in thread
From: Michal Miroslaw @ 2010-12-02 22:38 UTC (permalink / raw)
  To: Hein_Tibosch, Sahitya Tummala
  Cc: Andrew Morton, Pierre Ossman, Chris Ball, Ben Nizette,
	Sascha Hauer, Adrian Hunter, linux-mmc, linux-kernel,
	Matt Fleming

On Fri, Dec 03, 2010 at 05:21:10AM +0800, Hein_Tibosch wrote:
> Hi Sahitya,
> On 2-12-2010 19:16, Sahitya Tummala wrote:
> > Hi Hein Tibosch,
> >
> > On Fri, 2010-09-03 at 05:34 +0800, Hein_Tibosch wrote:
> >> In the latest releases of the mmc driver, the freq during initialization
> >> is set to a fixed 400 Khz. This was reportedly too fast for several
> >> users. As there doesn't seem to be an ideal frequency which-works-for-all,
> >> Pierre suggested to let the driver try several frequencies.
> >> <cut>
> >> +		/*
> >> +		 * First we search for SDIO...
> >> +		 */
> >> +		err = mmc_send_io_op_cond(host, 0, &ocr);
> >> +		if (!err) {
> >> +			if (mmc_attach_sdio(host, ocr)) {
> >> +				mmc_claim_host(host);
> >> +				/* try SDMEM (but not MMC) even if SDIO is broken */
> >> +				if (mmc_send_app_op_cond(host, 0, &ocr))
> > In case of SDIO error, mmc_power_off() is getting called as part of
> > mmc_detach_bus().  Shouldn't we power up the host before checking for
> > SDMEM? Any comments?
> I think you should ask Michal Miroslaw, as he wrote the patch for the
> SD-combo (IO + mem)*
> 
> But yes, in case of a failure, mmc_attach_sdio() will call mmc_detach_bus()
> which in turn will call mmc_power_off()
> 
> And so it should be mmc_power_up() again before trying to detect SD memory.

Yes, you are right!  This explains some things...

Please try attached patch. (Not tested, but obvious enough.)

Best Regards,
Michał Mirosław

---

mmc: fix detection of memory part of SD-combo card with broken SDIO

In case of failure, mmc_attach_sdio() will power off the SD bus.
Power it up and reinitialize before trying SD memory detection.

Reported-by: Sahitya Tummala <stummala@codeaurora.org>
Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
---
 drivers/mmc/core/core.c |    5 +++++
 1 files changed, 5 insertions(+), 0 deletions(-)

diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c
index 6286898..32a4798 100644
--- a/drivers/mmc/core/core.c
+++ b/drivers/mmc/core/core.c
@@ -1564,6 +1564,11 @@ void mmc_rescan(struct work_struct *work)
 				 * Try SDMEM (but not MMC) even if SDIO
 				 * is broken.
 				 */
+				mmc_power_up(host);
+				sdio_reset(host);
+				mmc_go_idle(host);
+				mmc_send_if_cond(host, host->ocr_avail);
+
 				if (mmc_send_app_op_cond(host, 0, &ocr))
 					goto out_fail;
 
-- 
1.7.2.3


^ permalink raw reply related	[flat|nested] 13+ messages in thread

* Re: [PATCH v4] mmc: Make ID freq configurable
  2010-12-02 22:38     ` Michal Miroslaw
@ 2010-12-03  5:05       ` stummala
  2010-12-03  6:56         ` Michal Miroslaw
  2010-12-17  1:09       ` Chris Ball
  1 sibling, 1 reply; 13+ messages in thread
From: stummala @ 2010-12-03  5:05 UTC (permalink / raw)
  To: Michal Miroslaw
  Cc: Hein_Tibosch, Sahitya Tummala, Andrew Morton, Pierre Ossman,
	Chris Ball, Ben Nizette, Sascha Hauer, Adrian Hunter, linux-mmc,
	linux-kernel, Matt Fleming

Hi Michal,

> On Fri, Dec 03, 2010 at 05:21:10AM +0800, Hein_Tibosch wrote:
>> Hi Sahitya,
>> On 2-12-2010 19:16, Sahitya Tummala wrote:
>> > Hi Hein Tibosch,
>> >
>> > On Fri, 2010-09-03 at 05:34 +0800, Hein_Tibosch wrote:
>> >> In the latest releases of the mmc driver, the freq during
>> initialization
>> >> is set to a fixed 400 Khz. This was reportedly too fast for several
>> >> users. As there doesn't seem to be an ideal frequency
>> which-works-for-all,
>> >> Pierre suggested to let the driver try several frequencies.
>> >> <cut>
>> >> +		/*
>> >> +		 * First we search for SDIO...
>> >> +		 */
>> >> +		err = mmc_send_io_op_cond(host, 0, &ocr);
>> >> +		if (!err) {
>> >> +			if (mmc_attach_sdio(host, ocr)) {
>> >> +				mmc_claim_host(host);
>> >> +				/* try SDMEM (but not MMC) even if SDIO is broken */
>> >> +				if (mmc_send_app_op_cond(host, 0, &ocr))
>> > In case of SDIO error, mmc_power_off() is getting called as part of
>> > mmc_detach_bus().  Shouldn't we power up the host before checking for
>> > SDMEM? Any comments?
>> I think you should ask Michal Miroslaw, as he wrote the patch for the
>> SD-combo (IO + mem)*
>>
>> But yes, in case of a failure, mmc_attach_sdio() will call
>> mmc_detach_bus()
>> which in turn will call mmc_power_off()
>>
>> And so it should be mmc_power_up() again before trying to detect SD
>> memory.
>
> Yes, you are right!  This explains some things...
>
> Please try attached patch. (Not tested, but obvious enough.)

I was looking at the code and figured out this issue. I don't have any
SD-combo card to verify your patch.

Thanks
Sahitya.
--
Sent by a consultant of the Qualcomm Innovation Center, Inc.
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora
Forum.

> Best Regards,
> Micha³ Miros³aw
>
> ---
>
> mmc: fix detection of memory part of SD-combo card with broken SDIO
>
> In case of failure, mmc_attach_sdio() will power off the SD bus.
> Power it up and reinitialize before trying SD memory detection.
>
> Reported-by: Sahitya Tummala <stummala@codeaurora.org>
> Signed-off-by: Micha³ Miros³aw <mirq-linux@rere.qmqm.pl>
> ---
>  drivers/mmc/core/core.c |    5 +++++
>  1 files changed, 5 insertions(+), 0 deletions(-)
>
> diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c
> index 6286898..32a4798 100644
> --- a/drivers/mmc/core/core.c
> +++ b/drivers/mmc/core/core.c
> @@ -1564,6 +1564,11 @@ void mmc_rescan(struct work_struct *work)
>  				 * Try SDMEM (but not MMC) even if SDIO
>  				 * is broken.
>  				 */
> +				mmc_power_up(host);
> +				sdio_reset(host);
> +				mmc_go_idle(host);
> +				mmc_send_if_cond(host, host->ocr_avail);
> +
>  				if (mmc_send_app_op_cond(host, 0, &ocr))
>  					goto out_fail;
>
> --
> 1.7.2.3
>
>



^ permalink raw reply	[flat|nested] 13+ messages in thread

* Re: [PATCH v4] mmc: Make ID freq configurable
  2010-12-03  5:05       ` stummala
@ 2010-12-03  6:56         ` Michal Miroslaw
  0 siblings, 0 replies; 13+ messages in thread
From: Michal Miroslaw @ 2010-12-03  6:56 UTC (permalink / raw)
  To: stummala
  Cc: Hein_Tibosch, Andrew Morton, Pierre Ossman, Chris Ball,
	Ben Nizette, Sascha Hauer, Adrian Hunter, linux-mmc, linux-kernel,
	Matt Fleming

On Thu, Dec 02, 2010 at 09:05:54PM -0800, stummala@codeaurora.org wrote:
> Hi Michal,
[...]
> >> > In case of SDIO error, mmc_power_off() is getting called as part of
> >> > mmc_detach_bus().  Shouldn't we power up the host before checking for
> >> > SDMEM? Any comments?
> >> I think you should ask Michal Miroslaw, as he wrote the patch for the
> >> SD-combo (IO + mem)*
> >>
> >> But yes, in case of a failure, mmc_attach_sdio() will call
> >> mmc_detach_bus()
> >> which in turn will call mmc_power_off()
> >>
> >> And so it should be mmc_power_up() again before trying to detect SD
> >> memory.
> > Yes, you are right!  This explains some things...
> >
> > Please try attached patch. (Not tested, but obvious enough.)
> I was looking at the code and figured out this issue. I don't have any
> SD-combo card to verify your patch.

You shouldn't be able to use this code path with normal SD-combo cards.
This is relevant if you have a card that responds to CMD5 but then fails
SDIO part initialization in some circumstances (i.e. time-outs).

Best Regards,
Michał Mirosław

^ permalink raw reply	[flat|nested] 13+ messages in thread

* Re: [PATCH v4] mmc: Make ID freq configurable
  2010-12-02 22:38     ` Michal Miroslaw
  2010-12-03  5:05       ` stummala
@ 2010-12-17  1:09       ` Chris Ball
  1 sibling, 0 replies; 13+ messages in thread
From: Chris Ball @ 2010-12-17  1:09 UTC (permalink / raw)
  To: Michal Miroslaw
  Cc: Hein_Tibosch, Sahitya Tummala, Andrew Morton, Pierre Ossman,
	Ben Nizette, Sascha Hauer, Adrian Hunter, linux-mmc, linux-kernel,
	Matt Fleming

Hi Michał, Sahitya,

On Thu, Dec 02, 2010 at 11:38:12PM +0100, Michal Miroslaw wrote:
> mmc: fix detection of memory part of SD-combo card with broken SDIO
> 
> In case of failure, mmc_attach_sdio() will power off the SD bus.
> Power it up and reinitialize before trying SD memory detection.
> 
> Reported-by: Sahitya Tummala <stummala@codeaurora.org>
> Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>

Thanks, this looks correct to me too; I've pushed it to mmc-next for .38.

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

^ permalink raw reply	[flat|nested] 13+ messages in thread

end of thread, other threads:[~2010-12-17  1:10 UTC | newest]

Thread overview: 13+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2010-09-02 21:34 [PATCH v4] mmc: Make ID freq configurable Hein_Tibosch
2010-09-03  1:47 ` Chris Ball
2010-09-03 23:25   ` Andrew Morton
2010-09-05 20:14 ` Matt Fleming
2010-09-05 20:43   ` Chris Ball
2010-09-05 21:22     ` Matt Fleming
2010-09-06  1:37       ` [PATCH v5] " Hein_Tibosch
2010-12-02 11:16 ` [PATCH v4] " Sahitya Tummala
2010-12-02 21:21   ` Hein_Tibosch
2010-12-02 22:38     ` Michal Miroslaw
2010-12-03  5:05       ` stummala
2010-12-03  6:56         ` Michal Miroslaw
2010-12-17  1:09       ` Chris Ball

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).