[PATCH 1/3] mmc: Auto CMD12 support for eSDHC driver

[PATCH 1/3] mmc: Auto CMD12 support for eSDHC driver

[Roy Zang]

From: Jerry Huang <Chang-Ming.Huang@freescale.com>

Add auto CMD12 command support for eSDHC driver.
This is needed by P4080 and P1022 for block read/write.
Manual asynchronous CMD12 abort operation causes protocol violations on
these silicons.

Signed-off-by: Jerry Huang <Chang-Ming.Huang@freescale.com>
Signed-off-by: Roy Zang <tie-fei.zang@freescale.com>
---
 drivers/mmc/host/sdhci-of-core.c |    4 ++++
 drivers/mmc/host/sdhci.c         |   14 ++++++++++++--
 drivers/mmc/host/sdhci.h         |    3 +++
 3 files changed, 19 insertions(+), 2 deletions(-)

diff --git a/drivers/mmc/host/sdhci-of-core.c b/drivers/mmc/host/sdhci-of-core.c
index a2e9820..0c30242 100644
--- a/drivers/mmc/host/sdhci-of-core.c
+++ b/drivers/mmc/host/sdhci-of-core.c
@@ -154,6 +154,10 @@ static int __devinit sdhci_of_probe(struct of_device *ofdev,
 		host->ops = &sdhci_of_data->ops;
 	}
 
+	if (of_get_property(np, "fsl,sdhci-auto-cmd12", NULL))
+		host->quirks |= SDHCI_QUIRK_MULTIBLOCK_READ_ACMD12;
+
+
 	if (of_get_property(np, "sdhci,1-bit-only", NULL))
 		host->quirks |= SDHCI_QUIRK_FORCE_1_BIT_DATA;
 
diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
index c6d1bd8..1424d08 100644
--- a/drivers/mmc/host/sdhci.c
+++ b/drivers/mmc/host/sdhci.c
@@ -2,6 +2,7 @@
  *  linux/drivers/mmc/host/sdhci.c - Secure Digital Host Controller Interface driver
  *
  *  Copyright (C) 2005-2008 Pierre Ossman, All Rights Reserved.
+ * Copyright 2010 Freescale Semiconductor, Inc.
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -817,8 +818,12 @@ static void sdhci_set_transfer_mode(struct sdhci_host *host,
 	WARN_ON(!host->data);
 
 	mode = SDHCI_TRNS_BLK_CNT_EN;
-	if (data->blocks > 1)
-		mode |= SDHCI_TRNS_MULTI;
+	if (data->blocks > 1) {
+		if (host->quirks & SDHCI_QUIRK_MULTIBLOCK_READ_ACMD12)
+			mode |= SDHCI_TRNS_MULTI | SDHCI_TRNS_ACMD12;
+		else
+			mode |= SDHCI_TRNS_MULTI;
+	}
 	if (data->flags & MMC_DATA_READ)
 		mode |= SDHCI_TRNS_READ;
 	if (host->flags & SDHCI_REQ_USE_DMA)
@@ -1108,6 +1113,11 @@ static void sdhci_request(struct mmc_host *mmc, struct mmc_request *mrq)
 #ifndef SDHCI_USE_LEDS_CLASS
 	sdhci_activate_led(host);
 #endif
+	if (host->quirks & SDHCI_QUIRK_MULTIBLOCK_READ_ACMD12)
+		if (mrq->stop) {
+			mrq->data->stop = NULL;
+			mrq->stop = NULL;
+		}
 
 	host->mrq = mrq;
 
diff --git a/drivers/mmc/host/sdhci.h b/drivers/mmc/host/sdhci.h
index c846813..aa112aa 100644
--- a/drivers/mmc/host/sdhci.h
+++ b/drivers/mmc/host/sdhci.h
@@ -2,6 +2,7 @@
  *  linux/drivers/mmc/host/sdhci.h - Secure Digital Host Controller Interface driver
  *
  *  Copyright (C) 2005-2008 Pierre Ossman, All Rights Reserved.
+ * Copyright 2010 Freescale Semiconductor, Inc.
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -240,6 +241,8 @@ struct sdhci_host {
 #define SDHCI_QUIRK_CAP_CLOCK_BASE_BROKEN		(1<<25)
 /* Controller cannot support End Attribute in NOP ADMA descriptor */
 #define SDHCI_QUIRK_NO_ENDATTR_IN_NOPDESC		(1<<26)
+/* Controller uses Auto CMD12 command to stop the transfer */
+#define SDHCI_QUIRK_MULTIBLOCK_READ_ACMD12		(1<<27)
 
 	int			irq;		/* Device IRQ */
 	void __iomem *		ioaddr;		/* Mapped address */
-- 
1.5.6.5

Re: [PATCH 1/3] mmc: Auto CMD12 support for eSDHC driver

[Anton Vorontsov]

On Wed, Jul 28, 2010 at 01:42:33PM +0800, Roy Zang wrote:
[...]
> +	if (host->quirks & SDHCI_QUIRK_MULTIBLOCK_READ_ACMD12)
> +		if (mrq->stop) {
> +			mrq->data->stop = NULL;
> +			mrq->stop = NULL;
> +		}

Please put additional curly braces for the first 'if' statement.

>  	host->mrq = mrq;
>  
> diff --git a/drivers/mmc/host/sdhci.h b/drivers/mmc/host/sdhci.h
> index c846813..aa112aa 100644
> --- a/drivers/mmc/host/sdhci.h
> +++ b/drivers/mmc/host/sdhci.h
> @@ -2,6 +2,7 @@
>   *  linux/drivers/mmc/host/sdhci.h - Secure Digital Host Controller Interface driver
>   *
>   *  Copyright (C) 2005-2008 Pierre Ossman, All Rights Reserved.
> + * Copyright 2010 Freescale Semiconductor, Inc.

Wrong count of spaces after '*'.

Also, according to git shortlog it's Freescale's first
patch to sdhci core, and the patch is quite trivial.

IANAL, but please refrain from adding authorship or copyright
notices unless you have done some major contribution(s).

>   * This program is free software; you can redistribute it and/or modify
>   * it under the terms of the GNU General Public License as published by
> @@ -240,6 +241,8 @@ struct sdhci_host {
>  #define SDHCI_QUIRK_CAP_CLOCK_BASE_BROKEN		(1<<25)
>  /* Controller cannot support End Attribute in NOP ADMA descriptor */
>  #define SDHCI_QUIRK_NO_ENDATTR_IN_NOPDESC		(1<<26)
> +/* Controller uses Auto CMD12 command to stop the transfer */
> +#define SDHCI_QUIRK_MULTIBLOCK_READ_ACMD12		(1<<27)

Thanks,

-- 
Anton Vorontsov
email: cbouatmailru@gmail.com
irc://irc.freenode.net/bd2