[PATCH v3 0/4] Extend sdhci-esdhc-imx card_detect and write_protect support for mx5

[PATCH v3 0/4] Extend sdhci-esdhc-imx card_detect and write_protect support for mx5

[Shawn Guo]

The card-present polling for sdhci based driver is very expensive
in terms of the impact to system performance.  We observe a few
system performance issues from Freescale and Linaro on mx5 platforms,
which have been proved card polling related.

The patch set extends the current sdhci-esdhc-imx card_detect and
write_protect support to cover mx5 platforms, and solves above
performance issues.

Changes since v2:
 * Fix the issue reported by Arnaud Patard:
   http://article.gmane.org/gmane.linux.ports.arm.kernel/120790

Changes since v1:
 * Rebase on today's linux-next
 * Take the suggestion from Arnaud Patard to add default pdata in
   imx_add_sdhci_esdhc_imx(), to avoid touching every single board
   file for the platform_data changes
 * Add comment for sdhci.c change
 * Change ESDHC_CD(WP)_SIGNAL to ESDHC_CD(WP)_CONTROLLER for a more
   descriptive name
 * Add missing NONE case handling in esdhc_pltfm_get_ro
 * Improve a couple comment wording per suggestion from Wolfram Sang

Shawn Guo (4):
      mmc: sdhci: fix interrupt storm from card detection
      mmc: sdhci-esdhc-imx: SDHCI_CARD_PRESENT does not get cleared
      mmc: sdhci-esdhc-imx: remove "WP" from flag ESDHC_FLAG_GPIO_FOR_CD_WP
      mmc: sdhci-esdhc-imx: extend card_detect and write_protect support for mx5

 arch/arm/mach-imx/eukrea_mbimxsd25-baseboard.c     |    3 +-
 arch/arm/mach-imx/eukrea_mbimxsd35-baseboard.c     |    3 +-
 arch/arm/mach-imx/mach-mx25_3ds.c                  |    2 +
 arch/arm/mach-imx/mach-pcm043.c                    |    2 +
 arch/arm/mach-mx5/board-mx51_babbage.c             |   14 +-
 arch/arm/mach-mx5/board-mx53_loco.c                |    4 +
 .../plat-mxc/devices/platform-sdhci-esdhc-imx.c    |   12 ++
 arch/arm/plat-mxc/include/mach/esdhc.h             |   25 +++-
 drivers/mmc/host/sdhci-esdhc-imx.c                 |  136 ++++++++++++--------
 drivers/mmc/host/sdhci.c                           |   27 ++++-
 10 files changed, 161 insertions(+), 67 deletions(-)

[PATCH v3 1/4] mmc: sdhci: fix interrupt storm from card detection

[Shawn Guo]

The issue was initially found by Eric Benard as below.

http://permalink.gmane.org/gmane.linux.ports.arm.kernel/108031

Not sure about other SDHCI based controller, but on Freescale eSDHC,
the SDHCI_INT_CARD_INSERT bits will be immediately set again when it
gets cleared, if a card is inserted. The driver need to mask the irq
to prevent interrupt storm which will freeze the system.  And the
SDHCI_INT_CARD_REMOVE gets the same situation.

The patch fixes the problem based on the initial idea from
Eric Benard.

Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Cc: Eric Benard <eric@eukrea.com>
---
 drivers/mmc/host/sdhci.c |   27 +++++++++++++++++++++++----
 1 files changed, 23 insertions(+), 4 deletions(-)

diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
index 91d9892..d94e2b4 100644
--- a/drivers/mmc/host/sdhci.c
+++ b/drivers/mmc/host/sdhci.c
@@ -127,7 +127,9 @@ static void sdhci_mask_irqs(struct sdhci_host *host, u32 irqs)
 
 static void sdhci_set_card_detection(struct sdhci_host *host, bool enable)
 {
-	u32 irqs = SDHCI_INT_CARD_REMOVE | SDHCI_INT_CARD_INSERT;
+	u32 present = sdhci_readl(host, SDHCI_PRESENT_STATE) &
+		      SDHCI_CARD_PRESENT;
+	u32 irqs = present ? SDHCI_INT_CARD_REMOVE : SDHCI_INT_CARD_INSERT;
 
 	if (host->quirks & SDHCI_QUIRK_BROKEN_CARD_DETECTION)
 		return;
@@ -2154,13 +2156,30 @@ static irqreturn_t sdhci_irq(int irq, void *dev_id)
 		mmc_hostname(host->mmc), intmask);
 
 	if (intmask & (SDHCI_INT_CARD_INSERT | SDHCI_INT_CARD_REMOVE)) {
+		u32 present = sdhci_readl(host, SDHCI_PRESENT_STATE) &
+			      SDHCI_CARD_PRESENT;
+
+		/*
+		 * There is a observation on i.mx esdhc.  INSERT bit will be
+		 * immediately set again when it gets cleared, if a card is
+		 * inserted.  We have to mask the irq to prevent interrupt
+		 * storm which will freeze the system.  And the REMOVE gets
+		 * the same situation.
+		 *
+		 * More testing are needed here to ensure it works for other
+		 * platforms though.
+		 */
+		sdhci_mask_irqs(host, present ? SDHCI_INT_CARD_INSERT :
+						SDHCI_INT_CARD_REMOVE);
+		sdhci_unmask_irqs(host, present ? SDHCI_INT_CARD_REMOVE :
+						  SDHCI_INT_CARD_INSERT);
+
 		sdhci_writel(host, intmask & (SDHCI_INT_CARD_INSERT |
-			SDHCI_INT_CARD_REMOVE), SDHCI_INT_STATUS);
+			     SDHCI_INT_CARD_REMOVE), SDHCI_INT_STATUS);
+		intmask &= ~(SDHCI_INT_CARD_INSERT | SDHCI_INT_CARD_REMOVE);
 		tasklet_schedule(&host->card_tasklet);
 	}
 
-	intmask &= ~(SDHCI_INT_CARD_INSERT | SDHCI_INT_CARD_REMOVE);
-
 	if (intmask & SDHCI_INT_CMD_MASK) {
 		sdhci_writel(host, intmask & SDHCI_INT_CMD_MASK,
 			SDHCI_INT_STATUS);
-- 
1.7.4.1

[PATCH v3 2/4] mmc: sdhci-esdhc-imx: SDHCI_CARD_PRESENT does not get cleared

[Shawn Guo]

The function esdhc_readl_le intends to clear bit SDHCI_CARD_PRESENT,
when the card detect gpio tells there is no card.  But it does not
clear the bit actually.  The patch gives a fix on that.

Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
---
 drivers/mmc/host/sdhci-esdhc-imx.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/drivers/mmc/host/sdhci-esdhc-imx.c b/drivers/mmc/host/sdhci-esdhc-imx.c
index 248b8e5..94097c0 100644
--- a/drivers/mmc/host/sdhci-esdhc-imx.c
+++ b/drivers/mmc/host/sdhci-esdhc-imx.c
@@ -84,7 +84,7 @@ static u32 esdhc_readl_le(struct sdhci_host *host, int reg)
 		if (boarddata && gpio_is_valid(boarddata->cd_gpio)
 				&& gpio_get_value(boarddata->cd_gpio))
 			/* no card, if a valid gpio says so... */
-			val &= SDHCI_CARD_PRESENT;
+			val &= ~SDHCI_CARD_PRESENT;
 		else
 			/* ... in all other cases assume card is present */
 			val |= SDHCI_CARD_PRESENT;
-- 
1.7.4.1

[PATCH v3 3/4] mmc: sdhci-esdhc-imx: remove "WP" from flag ESDHC_FLAG_GPIO_FOR_CD_WP

[Shawn Guo]

The use of flag ESDHC_FLAG_GPIO_FOR_CD_WP is all CD related.  It does
not necessarily need to bother WP in the flag name.

Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
---
 drivers/mmc/host/sdhci-esdhc-imx.c |    8 ++++----
 1 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/mmc/host/sdhci-esdhc-imx.c b/drivers/mmc/host/sdhci-esdhc-imx.c
index 94097c0..79b7a9a 100644
--- a/drivers/mmc/host/sdhci-esdhc-imx.c
+++ b/drivers/mmc/host/sdhci-esdhc-imx.c
@@ -29,7 +29,7 @@
 #define SDHCI_VENDOR_SPEC		0xC0
 #define  SDHCI_VENDOR_SPEC_SDIO_QUIRK	0x00000002
 
-#define ESDHC_FLAG_GPIO_FOR_CD_WP	(1 << 0)
+#define ESDHC_FLAG_GPIO_FOR_CD		(1 << 0)
 /*
  * The CMDTYPE of the CMD register (offset 0xE) should be set to
  * "11" when the STOP CMD12 is issued on imx53 to abort one
@@ -77,7 +77,7 @@ static u32 esdhc_readl_le(struct sdhci_host *host, int reg)
 	u32 val = readl(host->ioaddr + reg);
 
 	if (unlikely((reg == SDHCI_PRESENT_STATE)
-			&& (imx_data->flags & ESDHC_FLAG_GPIO_FOR_CD_WP))) {
+			&& (imx_data->flags & ESDHC_FLAG_GPIO_FOR_CD))) {
 		struct esdhc_platform_data *boarddata =
 				host->mmc->parent->platform_data;
 
@@ -99,7 +99,7 @@ static void esdhc_writel_le(struct sdhci_host *host, u32 val, int reg)
 	struct pltfm_imx_data *imx_data = pltfm_host->priv;
 
 	if (unlikely((reg == SDHCI_INT_ENABLE || reg == SDHCI_SIGNAL_ENABLE)
-			&& (imx_data->flags & ESDHC_FLAG_GPIO_FOR_CD_WP)))
+			&& (imx_data->flags & ESDHC_FLAG_GPIO_FOR_CD)))
 		/*
 		 * these interrupts won't work with a custom card_detect gpio
 		 * (only applied to mx25/35)
@@ -308,7 +308,7 @@ static int __devinit sdhci_esdhc_imx_probe(struct platform_device *pdev)
 			goto no_card_detect_irq;
 		}
 
-		imx_data->flags |= ESDHC_FLAG_GPIO_FOR_CD_WP;
+		imx_data->flags |= ESDHC_FLAG_GPIO_FOR_CD;
 		/* Now we have a working card_detect again */
 		host->quirks &= ~SDHCI_QUIRK_BROKEN_CARD_DETECTION;
 	}
-- 
1.7.4.1

[PATCH v3 4/4] mmc: sdhci-esdhc-imx: extend card_detect and write_protect support for mx5

[Shawn Guo]

The patch extends card_detect and write_protect support to get mx5
family and more scenarios supported.  The changes include:

 * Turn platform_data from optional to mandatory
 * Add cd_types and wp_types into platform_data to cover more use
   cases
 * Remove the use of flag ESDHC_FLAG_GPIO_FOR_CD
 * Adjust some machine codes to adopt the platform_data changes
 * Work around the issue that software reset will get card detection
   circuit stop working

With this patch, card_detect and write_protect gets supported on
mx5 based platforms.

Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Acked-by: Wolfram Sang <w.sang@pengutronix.de>
---
 arch/arm/mach-imx/eukrea_mbimxsd25-baseboard.c     |    3 +-
 arch/arm/mach-imx/eukrea_mbimxsd35-baseboard.c     |    3 +-
 arch/arm/mach-imx/mach-mx25_3ds.c                  |    2 +
 arch/arm/mach-imx/mach-pcm043.c                    |    2 +
 arch/arm/mach-mx5/board-mx51_babbage.c             |   14 ++-
 arch/arm/mach-mx5/board-mx53_loco.c                |    4 +
 .../plat-mxc/devices/platform-sdhci-esdhc-imx.c    |   12 ++
 arch/arm/plat-mxc/include/mach/esdhc.h             |   25 +++-
 drivers/mmc/host/sdhci-esdhc-imx.c                 |  134 ++++++++++++--------
 9 files changed, 137 insertions(+), 62 deletions(-)

diff --git a/arch/arm/mach-imx/eukrea_mbimxsd25-baseboard.c b/arch/arm/mach-imx/eukrea_mbimxsd25-baseboard.c
index 01ebcb3..66e8726 100644
--- a/arch/arm/mach-imx/eukrea_mbimxsd25-baseboard.c
+++ b/arch/arm/mach-imx/eukrea_mbimxsd25-baseboard.c
@@ -225,7 +225,8 @@ struct imx_ssi_platform_data eukrea_mbimxsd_ssi_pdata __initconst = {
 
 static struct esdhc_platform_data sd1_pdata = {
 	.cd_gpio = GPIO_SD1CD,
-	.wp_gpio = -EINVAL,
+	.cd_type = ESDHC_CD_GPIO,
+	.wp_type = ESDHC_WP_NONE,
 };
 
 /*
diff --git a/arch/arm/mach-imx/eukrea_mbimxsd35-baseboard.c b/arch/arm/mach-imx/eukrea_mbimxsd35-baseboard.c
index 558eb52..0f0af02 100644
--- a/arch/arm/mach-imx/eukrea_mbimxsd35-baseboard.c
+++ b/arch/arm/mach-imx/eukrea_mbimxsd35-baseboard.c
@@ -236,7 +236,8 @@ struct imx_ssi_platform_data eukrea_mbimxsd_ssi_pdata __initconst = {
 
 static struct esdhc_platform_data sd1_pdata = {
 	.cd_gpio = GPIO_SD1CD,
-	.wp_gpio = -EINVAL,
+	.cd_type = ESDHC_CD_GPIO,
+	.wp_type = ESDHC_WP_NONE,
 };
 
 /*
diff --git a/arch/arm/mach-imx/mach-mx25_3ds.c b/arch/arm/mach-imx/mach-mx25_3ds.c
index 01534bb..7f66a91 100644
--- a/arch/arm/mach-imx/mach-mx25_3ds.c
+++ b/arch/arm/mach-imx/mach-mx25_3ds.c
@@ -215,6 +215,8 @@ static const struct imxi2c_platform_data mx25_3ds_i2c0_data __initconst = {
 static const struct esdhc_platform_data mx25pdk_esdhc_pdata __initconst = {
 	.wp_gpio = SD1_GPIO_WP,
 	.cd_gpio = SD1_GPIO_CD,
+	.wp_type = ESDHC_WP_GPIO,
+	.cd_type = ESDHC_CD_GPIO,
 };
 
 static void __init mx25pdk_init(void)
diff --git a/arch/arm/mach-imx/mach-pcm043.c b/arch/arm/mach-imx/mach-pcm043.c
index 163cc31..660ec3e 100644
--- a/arch/arm/mach-imx/mach-pcm043.c
+++ b/arch/arm/mach-imx/mach-pcm043.c
@@ -349,6 +349,8 @@ __setup("otg_mode=", pcm043_otg_mode);
 static struct esdhc_platform_data sd1_pdata = {
 	.wp_gpio = SD1_GPIO_WP,
 	.cd_gpio = SD1_GPIO_CD,
+	.wp_type = ESDHC_WP_GPIO,
+	.cd_type = ESDHC_CD_GPIO,
 };
 
 /*
diff --git a/arch/arm/mach-mx5/board-mx51_babbage.c b/arch/arm/mach-mx5/board-mx51_babbage.c
index 15c6000..e400b09 100644
--- a/arch/arm/mach-mx5/board-mx51_babbage.c
+++ b/arch/arm/mach-mx5/board-mx51_babbage.c
@@ -41,8 +41,6 @@
 #define BABBAGE_POWER_KEY	IMX_GPIO_NR(2, 21)
 #define BABBAGE_ECSPI1_CS0	IMX_GPIO_NR(4, 24)
 #define BABBAGE_ECSPI1_CS1	IMX_GPIO_NR(4, 25)
-#define BABBAGE_SD1_CD		IMX_GPIO_NR(1, 0)
-#define BABBAGE_SD1_WP		IMX_GPIO_NR(1, 1)
 #define BABBAGE_SD2_CD		IMX_GPIO_NR(1, 6)
 #define BABBAGE_SD2_WP		IMX_GPIO_NR(1, 5)
 
@@ -146,8 +144,9 @@ static iomux_v3_cfg_t mx51babbage_pads[] = {
 	MX51_PAD_SD1_DATA1__SD1_DATA1,
 	MX51_PAD_SD1_DATA2__SD1_DATA2,
 	MX51_PAD_SD1_DATA3__SD1_DATA3,
-	MX51_PAD_GPIO1_0__GPIO1_0,
-	MX51_PAD_GPIO1_1__GPIO1_1,
+	/* CD/WP from controller */
+	MX51_PAD_GPIO1_0__SD1_CD,
+	MX51_PAD_GPIO1_1__SD1_WP,
 
 	/* SD 2 */
 	MX51_PAD_SD2_CMD__SD2_CMD,
@@ -156,6 +155,7 @@ static iomux_v3_cfg_t mx51babbage_pads[] = {
 	MX51_PAD_SD2_DATA1__SD2_DATA1,
 	MX51_PAD_SD2_DATA2__SD2_DATA2,
 	MX51_PAD_SD2_DATA3__SD2_DATA3,
+	/* CD/WP gpio */
 	MX51_PAD_GPIO1_6__GPIO1_6,
 	MX51_PAD_GPIO1_5__GPIO1_5,
 
@@ -340,13 +340,15 @@ static const struct spi_imx_master mx51_babbage_spi_pdata __initconst = {
 };
 
 static const struct esdhc_platform_data mx51_babbage_sd1_data __initconst = {
-	.cd_gpio = BABBAGE_SD1_CD,
-	.wp_gpio = BABBAGE_SD1_WP,
+	.cd_type = ESDHC_CD_CONTROLLER,
+	.wp_type = ESDHC_WP_CONTROLLER,
 };
 
 static const struct esdhc_platform_data mx51_babbage_sd2_data __initconst = {
 	.cd_gpio = BABBAGE_SD2_CD,
 	.wp_gpio = BABBAGE_SD2_WP,
+	.cd_type = ESDHC_CD_GPIO,
+	.wp_type = ESDHC_WP_GPIO,
 };
 
 /*
diff --git a/arch/arm/mach-mx5/board-mx53_loco.c b/arch/arm/mach-mx5/board-mx53_loco.c
index 54be525..4e1d51d 100644
--- a/arch/arm/mach-mx5/board-mx53_loco.c
+++ b/arch/arm/mach-mx5/board-mx53_loco.c
@@ -210,11 +210,15 @@ static const struct gpio_keys_platform_data loco_button_data __initconst = {
 
 static const struct esdhc_platform_data mx53_loco_sd1_data __initconst = {
 	.cd_gpio = LOCO_SD1_CD,
+	.cd_type = ESDHC_CD_GPIO,
+	.wp_type = ESDHC_WP_NONE,
 };
 
 static const struct esdhc_platform_data mx53_loco_sd3_data __initconst = {
 	.cd_gpio = LOCO_SD3_CD,
 	.wp_gpio = LOCO_SD3_WP,
+	.cd_type = ESDHC_CD_GPIO,
+	.wp_type = ESDHC_WP_GPIO,
 };
 
 static inline void mx53_loco_fec_reset(void)
diff --git a/arch/arm/plat-mxc/devices/platform-sdhci-esdhc-imx.c b/arch/arm/plat-mxc/devices/platform-sdhci-esdhc-imx.c
index 6b2940b..79d6d71 100644
--- a/arch/arm/plat-mxc/devices/platform-sdhci-esdhc-imx.c
+++ b/arch/arm/plat-mxc/devices/platform-sdhci-esdhc-imx.c
@@ -65,6 +65,11 @@ imx53_sdhci_esdhc_imx_data[] __initconst = {
 };
 #endif /* ifdef CONFIG_SOC_IMX53 */
 
+static const struct esdhc_platform_data default_esdhc_pdata __initconst = {
+	.wp_type = ESDHC_WP_NONE,
+	.cd_type = ESDHC_CD_NONE,
+};
+
 struct platform_device *__init imx_add_sdhci_esdhc_imx(
 		const struct imx_sdhci_esdhc_imx_data *data,
 		const struct esdhc_platform_data *pdata)
@@ -81,6 +86,13 @@ struct platform_device *__init imx_add_sdhci_esdhc_imx(
 		},
 	};
 
+	/*
+	 * If machine does not provide pdata, use the default one
+	 * which means no WP/CD support
+	 */
+	if (!pdata)
+		pdata = &default_esdhc_pdata;
+
 	return imx_add_platform_device("sdhci-esdhc-imx", data->id, res,
 			ARRAY_SIZE(res), pdata, sizeof(*pdata));
 }
diff --git a/arch/arm/plat-mxc/include/mach/esdhc.h b/arch/arm/plat-mxc/include/mach/esdhc.h
index 86003f4..aaf9748 100644
--- a/arch/arm/plat-mxc/include/mach/esdhc.h
+++ b/arch/arm/plat-mxc/include/mach/esdhc.h
@@ -10,17 +10,34 @@
 #ifndef __ASM_ARCH_IMX_ESDHC_H
 #define __ASM_ARCH_IMX_ESDHC_H
 
+enum wp_types {
+	ESDHC_WP_NONE,		/* no WP, neither controller nor gpio */
+	ESDHC_WP_CONTROLLER,	/* mmc controller internal WP */
+	ESDHC_WP_GPIO,		/* external gpio pin for WP */
+};
+
+enum cd_types {
+	ESDHC_CD_NONE,		/* no CD, neither controller nor gpio */
+	ESDHC_CD_CONTROLLER,	/* mmc controller internal CD */
+	ESDHC_CD_GPIO,		/* external gpio pin for CD */
+	ESDHC_CD_PERMANENT,	/* no CD, card permanently wired to host */
+};
+
 /**
- * struct esdhc_platform_data - optional platform data for esdhc on i.MX
+ * struct esdhc_platform_data - platform data for esdhc on i.MX
  *
- * strongly recommended for i.MX25/35, not needed for other variants
+ * ESDHC_WP(CD)_CONTROLLER type is not available on i.MX25/35.
  *
- * @wp_gpio:	gpio for write_protect (-EINVAL if unused)
- * @cd_gpio:	gpio for card_detect interrupt (-EINVAL if unused)
+ * @wp_gpio:	gpio for write_protect
+ * @cd_gpio:	gpio for card_detect interrupt
+ * @wp_type:	type of write_protect method (see wp_types enum above)
+ * @cd_type:	type of card_detect method (see cd_types enum above)
  */
 
 struct esdhc_platform_data {
 	unsigned int wp_gpio;
 	unsigned int cd_gpio;
+	enum wp_types wp_type;
+	enum cd_types cd_type;
 };
 #endif /* __ASM_ARCH_IMX_ESDHC_H */
diff --git a/drivers/mmc/host/sdhci-esdhc-imx.c b/drivers/mmc/host/sdhci-esdhc-imx.c
index 79b7a9a..5949519 100644
--- a/drivers/mmc/host/sdhci-esdhc-imx.c
+++ b/drivers/mmc/host/sdhci-esdhc-imx.c
@@ -29,7 +29,6 @@
 #define SDHCI_VENDOR_SPEC		0xC0
 #define  SDHCI_VENDOR_SPEC_SDIO_QUIRK	0x00000002
 
-#define ESDHC_FLAG_GPIO_FOR_CD		(1 << 0)
 /*
  * The CMDTYPE of the CMD register (offset 0xE) should be set to
  * "11" when the STOP CMD12 is issued on imx53 to abort one
@@ -70,19 +69,15 @@ static inline void esdhc_clrset_le(struct sdhci_host *host, u32 mask, u32 val, i
 
 static u32 esdhc_readl_le(struct sdhci_host *host, int reg)
 {
-	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
-	struct pltfm_imx_data *imx_data = pltfm_host->priv;
+	struct esdhc_platform_data *boarddata =
+			host->mmc->parent->platform_data;
 
-	/* fake CARD_PRESENT flag on mx25/35 */
+	/* fake CARD_PRESENT flag */
 	u32 val = readl(host->ioaddr + reg);
 
 	if (unlikely((reg == SDHCI_PRESENT_STATE)
-			&& (imx_data->flags & ESDHC_FLAG_GPIO_FOR_CD))) {
-		struct esdhc_platform_data *boarddata =
-				host->mmc->parent->platform_data;
-
-		if (boarddata && gpio_is_valid(boarddata->cd_gpio)
-				&& gpio_get_value(boarddata->cd_gpio))
+			&& gpio_is_valid(boarddata->cd_gpio))) {
+		if (gpio_get_value(boarddata->cd_gpio))
 			/* no card, if a valid gpio says so... */
 			val &= ~SDHCI_CARD_PRESENT;
 		else
@@ -97,12 +92,13 @@ static void esdhc_writel_le(struct sdhci_host *host, u32 val, int reg)
 {
 	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
 	struct pltfm_imx_data *imx_data = pltfm_host->priv;
+	struct esdhc_platform_data *boarddata =
+			host->mmc->parent->platform_data;
 
 	if (unlikely((reg == SDHCI_INT_ENABLE || reg == SDHCI_SIGNAL_ENABLE)
-			&& (imx_data->flags & ESDHC_FLAG_GPIO_FOR_CD)))
+			&& (boarddata->cd_type == ESDHC_CD_GPIO)))
 		/*
 		 * these interrupts won't work with a custom card_detect gpio
-		 * (only applied to mx25/35)
 		 */
 		val &= ~(SDHCI_INT_CARD_REMOVE | SDHCI_INT_CARD_INSERT);
 
@@ -185,6 +181,17 @@ static void esdhc_writeb_le(struct sdhci_host *host, u8 val, int reg)
 		return;
 	}
 	esdhc_clrset_le(host, 0xff, val, reg);
+
+	/*
+	 * The esdhc has a design violation to SDHC spec which tells
+	 * that software reset should not affect card detection circuit.
+	 * But esdhc clears its SYSCTL register bits [0..2] during the
+	 * software reset.  This will stop those clocks that card detection
+	 * circuit relies on.  To work around it, we turn the clocks on back
+	 * to keep card detection circuit functional.
+	 */
+	if ((reg == SDHCI_SOFTWARE_RESET) && (val & 1))
+		esdhc_clrset_le(host, 0x7, 0x7, ESDHC_SYSTEM_CONTROL);
 }
 
 static unsigned int esdhc_pltfm_get_max_clock(struct sdhci_host *host)
@@ -201,6 +208,25 @@ static unsigned int esdhc_pltfm_get_min_clock(struct sdhci_host *host)
 	return clk_get_rate(pltfm_host->clk) / 256 / 16;
 }
 
+static unsigned int esdhc_pltfm_get_ro(struct sdhci_host *host)
+{
+	struct esdhc_platform_data *boarddata =
+			host->mmc->parent->platform_data;
+
+	switch (boarddata->wp_type) {
+	case ESDHC_WP_GPIO:
+		if (gpio_is_valid(boarddata->wp_gpio))
+			return gpio_get_value(boarddata->wp_gpio);
+	case ESDHC_WP_CONTROLLER:
+		return !(readl(host->ioaddr + SDHCI_PRESENT_STATE) &
+			       SDHCI_WRITE_PROTECT);
+	case ESDHC_WP_NONE:
+		break;
+	}
+
+	return -ENOSYS;
+}
+
 static struct sdhci_ops sdhci_esdhc_ops = {
 	.read_l = esdhc_readl_le,
 	.read_w = esdhc_readw_le,
@@ -212,6 +238,7 @@ static struct sdhci_ops sdhci_esdhc_ops = {
 	.get_min_clock = esdhc_pltfm_get_min_clock,
 	.get_max_blk_size = esdhc_pltfm_get_max_blk_size,
 	.get_max_blk_count = esdhc_pltfm_get_max_blk_count,
+	.get_ro = esdhc_pltfm_get_ro,
 };
 
 static struct sdhci_pltfm_data sdhci_esdhc_imx_pdata = {
@@ -221,17 +248,6 @@ static struct sdhci_pltfm_data sdhci_esdhc_imx_pdata = {
 	.ops = &sdhci_esdhc_ops,
 };
 
-static unsigned int esdhc_pltfm_get_ro(struct sdhci_host *host)
-{
-	struct esdhc_platform_data *boarddata =
-			host->mmc->parent->platform_data;
-
-	if (boarddata && gpio_is_valid(boarddata->wp_gpio))
-		return gpio_get_value(boarddata->wp_gpio);
-	else
-		return -ENOSYS;
-}
-
 static irqreturn_t cd_irq(int irq, void *data)
 {
 	struct sdhci_host *sdhost = (struct sdhci_host *)data;
@@ -272,23 +288,34 @@ static int __devinit sdhci_esdhc_imx_probe(struct platform_device *pdev)
 	if (!cpu_is_mx25())
 		host->quirks |= SDHCI_QUIRK_BROKEN_TIMEOUT_VAL;
 
-	if (cpu_is_mx25() || cpu_is_mx35()) {
-		/* write_protect can't be routed to controller, use gpio */
-		sdhci_esdhc_ops.get_ro = esdhc_pltfm_get_ro;
-	}
-
 	if (!(cpu_is_mx25() || cpu_is_mx35() || cpu_is_mx51()))
 		imx_data->flags |= ESDHC_FLAG_MULTIBLK_NO_INT;
 
 	boarddata = host->mmc->parent->platform_data;
-	if (boarddata) {
+	if (!boarddata) {
+		dev_err(mmc_dev(host->mmc), "no board data!\n");
+		err = -EINVAL;
+		goto no_board_data;
+	}
+
+	/* write_protect */
+	if (boarddata->wp_type == ESDHC_WP_GPIO) {
 		err = gpio_request_one(boarddata->wp_gpio, GPIOF_IN, "ESDHC_WP");
 		if (err) {
 			dev_warn(mmc_dev(host->mmc),
-				"no write-protect pin available!\n");
-			boarddata->wp_gpio = err;
+				 "no write-protect pin available!\n");
+			boarddata->wp_gpio = -EINVAL;
 		}
+	} else {
+		boarddata->wp_gpio = -EINVAL;
+	}
 
+	/* card_detect */
+	if (boarddata->cd_type != ESDHC_CD_GPIO)
+		boarddata->cd_gpio = -EINVAL;
+
+	switch (boarddata->cd_type) {
+	case ESDHC_CD_GPIO:
 		err = gpio_request_one(boarddata->cd_gpio, GPIOF_IN, "ESDHC_CD");
 		if (err) {
 			dev_warn(mmc_dev(host->mmc),
@@ -296,10 +323,6 @@ static int __devinit sdhci_esdhc_imx_probe(struct platform_device *pdev)
 			goto no_card_detect_pin;
 		}
 
-		/* i.MX5x has issues to be researched */
-		if (!cpu_is_mx25() && !cpu_is_mx35())
-			goto not_supported;
-
 		err = request_irq(gpio_to_irq(boarddata->cd_gpio), cd_irq,
 				 IRQF_TRIGGER_FALLING | IRQF_TRIGGER_RISING,
 				 mmc_hostname(host->mmc), host);
@@ -307,10 +330,19 @@ static int __devinit sdhci_esdhc_imx_probe(struct platform_device *pdev)
 			dev_warn(mmc_dev(host->mmc), "request irq error\n");
 			goto no_card_detect_irq;
 		}
+		/* fall through */
 
-		imx_data->flags |= ESDHC_FLAG_GPIO_FOR_CD;
-		/* Now we have a working card_detect again */
+	case ESDHC_CD_CONTROLLER:
+		/* we have a working card_detect back */
 		host->quirks &= ~SDHCI_QUIRK_BROKEN_CARD_DETECTION;
+		break;
+
+	case ESDHC_CD_PERMANENT:
+		host->mmc->caps = MMC_CAP_NONREMOVABLE;
+		break;
+
+	case ESDHC_CD_NONE:
+		break;
 	}
 
 	err = sdhci_add_host(host);
@@ -319,16 +351,20 @@ static int __devinit sdhci_esdhc_imx_probe(struct platform_device *pdev)
 
 	return 0;
 
- no_card_detect_irq:
-	gpio_free(boarddata->cd_gpio);
- no_card_detect_pin:
-	boarddata->cd_gpio = err;
- not_supported:
-	kfree(imx_data);
- err_add_host:
+err_add_host:
+	if (gpio_is_valid(boarddata->cd_gpio))
+		free_irq(gpio_to_irq(boarddata->cd_gpio), host);
+no_card_detect_irq:
+	if (gpio_is_valid(boarddata->cd_gpio))
+		gpio_free(boarddata->cd_gpio);
+	if (gpio_is_valid(boarddata->wp_gpio))
+		gpio_free(boarddata->wp_gpio);
+no_card_detect_pin:
+no_board_data:
 	clk_disable(pltfm_host->clk);
 	clk_put(pltfm_host->clk);
- err_clk_get:
+err_clk_get:
+	kfree(imx_data);
 	sdhci_pltfm_free(pdev);
 	return err;
 }
@@ -343,14 +379,12 @@ static int __devexit sdhci_esdhc_imx_remove(struct platform_device *pdev)
 
 	sdhci_remove_host(host, dead);
 
-	if (boarddata && gpio_is_valid(boarddata->wp_gpio))
+	if (gpio_is_valid(boarddata->wp_gpio))
 		gpio_free(boarddata->wp_gpio);
 
-	if (boarddata && gpio_is_valid(boarddata->cd_gpio)) {
+	if (gpio_is_valid(boarddata->cd_gpio)) {
+		free_irq(gpio_to_irq(boarddata->cd_gpio), host);
 		gpio_free(boarddata->cd_gpio);
-
-		if (!(host->quirks & SDHCI_QUIRK_BROKEN_CARD_DETECTION))
-			free_irq(gpio_to_irq(boarddata->cd_gpio), host);
 	}
 
 	clk_disable(pltfm_host->clk);
-- 
1.7.4.1

[PATCH v3 1/4] mmc: sdhci: fix interrupt storm from card detection

[Philip Rakity]

On Jun 20, 2011, at 3:38 AM, Shawn Guo wrote:

> The issue was initially found by Eric Benard as below.
> 
> http://permalink.gmane.org/gmane.linux.ports.arm.kernel/108031
> 
> Not sure about other SDHCI based controller, but on Freescale eSDHC,
> the SDHCI_INT_CARD_INSERT bits will be immediately set again when it
> gets cleared, if a card is inserted. The driver need to mask the irq
> to prevent interrupt storm which will freeze the system.  And the
> SDHCI_INT_CARD_REMOVE gets the same situation.
> 
> The patch fixes the problem based on the initial idea from
> Eric Benard.
> 
> Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
> Cc: Eric Benard <eric@eukrea.com>
> ---
> drivers/mmc/host/sdhci.c |   27 +++++++++++++++++++++++----
> 1 files changed, 23 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
> index 91d9892..d94e2b4 100644
> --- a/drivers/mmc/host/sdhci.c
> +++ b/drivers/mmc/host/sdhci.c
> @@ -127,7 +127,9 @@ static void sdhci_mask_irqs(struct sdhci_host *host, u32 irqs)
> 
> static void sdhci_set_card_detection(struct sdhci_host *host, bool enable)
> {
> -	u32 irqs = SDHCI_INT_CARD_REMOVE | SDHCI_INT_CARD_INSERT;
> +	u32 present = sdhci_readl(host, SDHCI_PRESENT_STATE) &
> +		      SDHCI_CARD_PRESENT;
> +	u32 irqs = present ? SDHCI_INT_CARD_REMOVE : SDHCI_INT_CARD_INSERT;
> 
> 	if (host->quirks & SDHCI_QUIRK_BROKEN_CARD_DETECTION)
> 		return;


Accessing off chip registers is slow.  It would be better to check for the quirk first
and then read the present state register.

eg
	
	u32 present;
	u32 irqs;	

> 	if (host->quirks & SDHCI_QUIRK_BROKEN_CARD_DETECTION)
> 		return;

>  	present = sdhci_readl(host, SDHCI_PRESENT_STATE) &
> 		      SDHCI_CARD_PRESENT;


> 	irqs = present ? SDHCI_INT_CARD_REMOVE : SDHCI_INT_CARD_INSERT;


Philip

[PATCH v3 1/4] mmc: sdhci: fix interrupt storm from card detection

[Shawn Guo]

On Mon, Jun 20, 2011 at 08:59:38AM -0700, Philip Rakity wrote:
> 
> On Jun 20, 2011, at 3:38 AM, Shawn Guo wrote:
> 
> > The issue was initially found by Eric Benard as below.
> > 
> > http://permalink.gmane.org/gmane.linux.ports.arm.kernel/108031
> > 
> > Not sure about other SDHCI based controller, but on Freescale eSDHC,
> > the SDHCI_INT_CARD_INSERT bits will be immediately set again when it
> > gets cleared, if a card is inserted. The driver need to mask the irq
> > to prevent interrupt storm which will freeze the system.  And the
> > SDHCI_INT_CARD_REMOVE gets the same situation.
> > 
> > The patch fixes the problem based on the initial idea from
> > Eric Benard.
> > 
> > Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
> > Cc: Eric Benard <eric@eukrea.com>
> > ---
> > drivers/mmc/host/sdhci.c |   27 +++++++++++++++++++++++----
> > 1 files changed, 23 insertions(+), 4 deletions(-)
> > 
> > diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
> > index 91d9892..d94e2b4 100644
> > --- a/drivers/mmc/host/sdhci.c
> > +++ b/drivers/mmc/host/sdhci.c
> > @@ -127,7 +127,9 @@ static void sdhci_mask_irqs(struct sdhci_host *host, u32 irqs)
> > 
> > static void sdhci_set_card_detection(struct sdhci_host *host, bool enable)
> > {
> > -	u32 irqs = SDHCI_INT_CARD_REMOVE | SDHCI_INT_CARD_INSERT;
> > +	u32 present = sdhci_readl(host, SDHCI_PRESENT_STATE) &
> > +		      SDHCI_CARD_PRESENT;
> > +	u32 irqs = present ? SDHCI_INT_CARD_REMOVE : SDHCI_INT_CARD_INSERT;
> > 
> > 	if (host->quirks & SDHCI_QUIRK_BROKEN_CARD_DETECTION)
> > 		return;
> 
> 
> Accessing off chip registers is slow.  It would be better to check for the quirk first
> and then read the present state register.
> 
> eg
> 	
> 	u32 present;
> 	u32 irqs;	
> 
> > 	if (host->quirks & SDHCI_QUIRK_BROKEN_CARD_DETECTION)
> > 		return;
> 
> >  	present = sdhci_readl(host, SDHCI_PRESENT_STATE) &
> > 		      SDHCI_CARD_PRESENT;
> 
> 
> > 	irqs = present ? SDHCI_INT_CARD_REMOVE : SDHCI_INT_CARD_INSERT;
> 
Makes sense.  Will do.

-- 
Regards,
Shawn

[PATCH v3 0/4] Extend sdhci-esdhc-imx card_detect and write_protect support for mx5

[Shawn Guo]

Hi Arnaud,

Would you please give a test on the series, as it fixed the issue
you reported?  TIA.

-- 
Regards,
Shawn

On Mon, Jun 20, 2011 at 06:38:41PM +0800, Shawn Guo wrote:
> The card-present polling for sdhci based driver is very expensive
> in terms of the impact to system performance.  We observe a few
> system performance issues from Freescale and Linaro on mx5 platforms,
> which have been proved card polling related.
> 
> The patch set extends the current sdhci-esdhc-imx card_detect and
> write_protect support to cover mx5 platforms, and solves above
> performance issues.
> 
> Changes since v2:
>  * Fix the issue reported by Arnaud Patard:
>    http://article.gmane.org/gmane.linux.ports.arm.kernel/120790
> 
> Changes since v1:
>  * Rebase on today's linux-next
>  * Take the suggestion from Arnaud Patard to add default pdata in
>    imx_add_sdhci_esdhc_imx(), to avoid touching every single board
>    file for the platform_data changes
>  * Add comment for sdhci.c change
>  * Change ESDHC_CD(WP)_SIGNAL to ESDHC_CD(WP)_CONTROLLER for a more
>    descriptive name
>  * Add missing NONE case handling in esdhc_pltfm_get_ro
>  * Improve a couple comment wording per suggestion from Wolfram Sang
> 
> Shawn Guo (4):
>       mmc: sdhci: fix interrupt storm from card detection
>       mmc: sdhci-esdhc-imx: SDHCI_CARD_PRESENT does not get cleared
>       mmc: sdhci-esdhc-imx: remove "WP" from flag ESDHC_FLAG_GPIO_FOR_CD_WP
>       mmc: sdhci-esdhc-imx: extend card_detect and write_protect support for mx5
> 
>  arch/arm/mach-imx/eukrea_mbimxsd25-baseboard.c     |    3 +-
>  arch/arm/mach-imx/eukrea_mbimxsd35-baseboard.c     |    3 +-
>  arch/arm/mach-imx/mach-mx25_3ds.c                  |    2 +
>  arch/arm/mach-imx/mach-pcm043.c                    |    2 +
>  arch/arm/mach-mx5/board-mx51_babbage.c             |   14 +-
>  arch/arm/mach-mx5/board-mx53_loco.c                |    4 +
>  .../plat-mxc/devices/platform-sdhci-esdhc-imx.c    |   12 ++
>  arch/arm/plat-mxc/include/mach/esdhc.h             |   25 +++-
>  drivers/mmc/host/sdhci-esdhc-imx.c                 |  136 ++++++++++++--------
>  drivers/mmc/host/sdhci.c                           |   27 ++++-
>  10 files changed, 161 insertions(+), 67 deletions(-)
> --
> To unsubscribe from this list: send the line "unsubscribe linux-mmc" in
> the body of a message to majordomo at vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
> 

[PATCH v3 0/4] Extend sdhci-esdhc-imx card_detect and write_protect support for mx5

[Arnaud Patard (Rtp)]

Shawn Guo <shawn.guo@freescale.com> writes:

> Hi Arnaud,

Hi,

>
> Would you please give a test on the series, as it fixed the issue
> you reported?  TIA.

I've tested it yesterday on my efika platforms and the issue is
gone. Moreover, the differents card slot on theses platforms are using
each card detect type (internally connected, gpio, no card detect) and
they are all working as expected. I'm a little bit annoyed by the
polling on the slot without card detect but this has nothing to do with
this patchset.

Side note: turns out that the driver is using dev_warn when failing to
get cd gpio/irq. Given that in theses cases, it jumps to
no_card_detect_pin and makes the probe fail, maybe a dev_err would be
better ? 

Tested-by: Arnaud Patard <arnaud.patard@rtp-net.org>

Thanks,
Arnaud

[PATCH v3 2/4] mmc: sdhci-esdhc-imx: SDHCI_CARD_PRESENT does not get cleared

[Wolfram Sang]

On Mon, Jun 20, 2011 at 06:38:43PM +0800, Shawn Guo wrote:
> The function esdhc_readl_le intends to clear bit SDHCI_CARD_PRESENT,
> when the card detect gpio tells there is no card.  But it does not
> clear the bit actually.  The patch gives a fix on that.
> 
> Signed-off-by: Shawn Guo <shawn.guo@linaro.org>

For the third time ;)

Acked-by: Wolfram Sang <w.sang@pengutronix.de>

Should go to stable.

-- 
Pengutronix e.K.                           | Wolfram Sang                |
Industrial Linux Solutions                 | http://www.pengutronix.de/  |
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[PATCH v3 2/4] mmc: sdhci-esdhc-imx: SDHCI_CARD_PRESENT does not get cleared

[Chris Ball]

Hi Shawn,

On Tue, Jun 21 2011, Shawn Guo wrote:
>> Acked-by: Wolfram Sang <w.sang@pengutronix.de>
>> 
> Sorry, my bad.  Will add in v4.
>
>> Should go to stable.
>> 
> I suppose that Chris will take care of it, otherwise please let me
> know what I should do.  (I'm still new to the process)

Just add:

Cc: <stable@kernel.org>

to the commit message, please.  (That's all that's necessary to get a
patch seen by the stable@ maintainers.)

Thanks,

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

[PATCH v3 2/4] mmc: sdhci-esdhc-imx: SDHCI_CARD_PRESENT does not get cleared

[Shawn Guo]

On Tue, Jun 21, 2011 at 01:52:36PM +0200, Wolfram Sang wrote:
> On Mon, Jun 20, 2011 at 06:38:43PM +0800, Shawn Guo wrote:
> > The function esdhc_readl_le intends to clear bit SDHCI_CARD_PRESENT,
> > when the card detect gpio tells there is no card.  But it does not
> > clear the bit actually.  The patch gives a fix on that.
> > 
> > Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
> 
> For the third time ;)
> 
> Acked-by: Wolfram Sang <w.sang@pengutronix.de>
> 
Sorry, my bad.  Will add in v4.

> Should go to stable.
> 
I suppose that Chris will take care of it, otherwise please let me
know what I should do.  (I'm still new to the process)

-- 
Regards,
Shawn

[PATCH v3 0/4] Extend sdhci-esdhc-imx card_detect and write_protect support for mx5

[Shawn Guo]

On Tue, Jun 21, 2011 at 11:44:00AM +0200, Arnaud Patard wrote:
> Shawn Guo <shawn.guo@freescale.com> writes:
> 
> > Hi Arnaud,
> 
> Hi,
> 
> >
> > Would you please give a test on the series, as it fixed the issue
> > you reported?  TIA.
> 
> I've tested it yesterday on my efika platforms and the issue is
> gone. Moreover, the differents card slot on theses platforms are using
> each card detect type (internally connected, gpio, no card detect) and
> they are all working as expected. I'm a little bit annoyed by the
> polling on the slot without card detect but this has nothing to do with
> this patchset.
> 
That's great.

> Side note: turns out that the driver is using dev_warn when failing to
> get cd gpio/irq. Given that in theses cases, it jumps to
> no_card_detect_pin and makes the probe fail, maybe a dev_err would be
> better ? 
> 
Though it's the existing code, I respect the comment and will make the
change in the v4.

> Tested-by: Arnaud Patard <arnaud.patard@rtp-net.org>
> 
Thanks for testing.

-- 
Regards,
Shawn

[PATCH v3 2/4] mmc: sdhci-esdhc-imx: SDHCI_CARD_PRESENT does not get cleared

[Wolfram Sang]

> > Should go to stable.
> > 
> I suppose that Chris will take care of it,

That's correct. You can add the cc as Chris suggested, so the maintainer knows
that you think it should go to stable. The final decission is up to the
maintainer, though.

-- 
Pengutronix e.K.                           | Wolfram Sang                |
Industrial Linux Solutions                 | http://www.pengutronix.de/  |
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