[PATCH v13 0/7] mmc: omap_hsmmc: Enable SDIO IRQ

[PATCH v13 0/7] mmc: omap_hsmmc: Enable SDIO IRQ

[Andreas Fenkart]

Hi Balaji, Tony, Ulf, all

v13
- fix compile breaks if !CONFIG_PM
- additional patch: install dummy pm runtime hooks if !CONFIG_PM_RUNTIME

v12
- drop !CONFIG_OF compile break only exists when
  #undef CONFIG_OF after include headers 1/7(Sebastian Reichel)
- do not emit "falling back to polling" if wake_irq not specified
  since MMC does not need it, and it might confuse users
  only emit if pinmux default/idle is not present or claiming
  the irq failed 2/7(Balaji)
- dropped out-of-tree patches 6/7(Balaji)
- mention "ti,am33xx-hsmmc" compatible section in bindings
  documentation 1/5

v11
- split !CONFIG_OF compile break into separate patch
- enable IWE/CLKEXTFREE in CON/HCTL register needed for omap4
- '&' vs '&&' in omap_hsmmc_resume, 1/5 (Andreas Müller)
- #define DLEV_DAT instead of BIT(21) 2/5 (Balaji)
- pinctrl_pm_select_default_state() removed, 4/5 (Balaji)
- drop _irqsave/_irqrestore from omap_hsmmc_wake_irq handler since it
  can't be preempted by same priority omap_hsmmc_irq handler 1/5(Joel Fernandes)
- replace devres_open_group by explicit devm_free calls 1/5 (Balaji)
- disable_irq_nosync wake_irq since we handle it thread safe 1/5 (Balaji)
- drop 'gpio_dat1' pinctrl states and rework documentation 5/5 (Balaji)

v10
- bug fix on multi-core, untested
- incorporated changes from Balaji
- use devres / RAII mechanism to configure wake_up /
  sdio irq capabilities
- drop pinctrl state 'active'
  rely on driver-model states 'default', 'idle'
- add specific 'gpio_dat1' state for am335x SWAKEUP hack
- reorganized patches; +1 patch multi-core bugfix / +1 for pinctrl
- rebased 455c6fdbd21916 / cherry-picks from mmc-next

v9
- extended comment about why wake-irq is needed
- drop double '(' ')' around card_detect_irq
- drop final '.' in in subject line of patch

v8
- rebased on top of Tony Lindgren<tony@atomide.com> changes
  - improved changelog describing the earlier work
  - improved wakeup irq setup
  - works for am3730 es platform now
- my changes on top:
  - compile tested with #undef CONFIG_OF
  - disable wake_irq in handler to prevent infinite loop  
  - fixed typo and added comment about wake-irq

v7
- rebase on 3.14.0-rc3-49726-g77e15ec
- split omap_hsmmc_pin_init due to regression on omap-3730 platform

v6
- rebase on Linux 3.13-rc3
- reformatting debugfs

v5
- fix compile error introduced by last minute one line fix

v4:
- switch to interrupts-extended format
- drop ti,swakeup-missing flag convert to comaptible section

v3:
- removed gpio_irq from platform_data

v2:
- incorparated changes as suggested by reviewers
- simplified workaround for am335x, gpio will now only wake
  the module from runtime suspend, not handle the sdio irq
  itself 

Andreas Fenkart (7):
  mmc: omap_hsmmc: install dummy pm runtime hooks if !CONFIG_PM_RUNTIME
  mmc: omap_hsmmc: Enable SDIO interrupt
  mmc: omap_hsmmc: Extend debugfs by SDIO IRQ handling, runtime state
  mmc: omap_hsmmc: enable wakeup event for sdio OMAP4
  mmc: omap_hsmmc: abort runtime suspend if pending sdio irq detected
  mmc: omap_hsmmc: switch default/idle pinctrl states in runtime hooks
  mmc: omap_hsmmc: Pin remux workaround to support SDIO interrupt on
    AM335x

 .../devicetree/bindings/mmc/ti-omap-hsmmc.txt      |   54 ++++
 drivers/mmc/host/omap_hsmmc.c                      |  309 ++++++++++++++++++--
 include/linux/platform_data/mmc-omap.h             |    1 +
 3 files changed, 335 insertions(+), 29 deletions(-)

-- 
1.7.10.4

[PATCH v13 1/7] mmc: omap_hsmmc: install dummy pm runtime hooks if !CONFIG_PM_RUNTIME

[Andreas Fenkart]

Signed-off-by: Andreas Fenkart <afenkart@gmail.com>

diff --git a/drivers/mmc/host/omap_hsmmc.c b/drivers/mmc/host/omap_hsmmc.c
index 272e0ee..c62d9dd 100644
--- a/drivers/mmc/host/omap_hsmmc.c
+++ b/drivers/mmc/host/omap_hsmmc.c
@@ -199,7 +199,9 @@ struct omap_hsmmc_host {
 	struct dma_chan		*rx_chan;
 	int			slot_id;
 	int			response_busy;
+#ifdef CONFIG_PM
 	int			context_loss;
+#endif
 	int			protect_card;
 	int			reqs_blocked;
 	int			use_reg;
@@ -712,14 +714,8 @@ static void omap_hsmmc_context_save(struct omap_hsmmc_host *host)
 
 #else
 
-static int omap_hsmmc_context_restore(struct omap_hsmmc_host *host)
-{
-	return 0;
-}
-
-static void omap_hsmmc_context_save(struct omap_hsmmc_host *host)
-{
-}
+#define omap_hsmmc_context_restore(host)
+#define omap_hsmmc_context_save(host)
 
 #endif
 
@@ -1700,11 +1696,14 @@ static int omap_hsmmc_regs_show(struct seq_file *s, void *data)
 	struct mmc_host *mmc = s->private;
 	struct omap_hsmmc_host *host = mmc_priv(mmc);
 
-	seq_printf(s, "mmc%d:\n ctx_loss:\t%d\n\nregs:\n",
-			mmc->index, host->context_loss);
+	seq_printf(s, "mmc%d:\n", mmc->index);
 
-	pm_runtime_get_sync(host->dev);
+#ifdef CONFIG_PM
+	seq_printf(s, "ctx_loss:\t%d\n", host->context_loss);
+#endif
 
+	pm_runtime_get_sync(host->dev);
+	seq_puts(s, "\nregs:\n");
 	seq_printf(s, "CON:\t\t0x%08x\n",
 			OMAP_HSMMC_READ(host->base, CON));
 	seq_printf(s, "HCTL:\t\t0x%08x\n",
@@ -2243,6 +2242,7 @@ static int omap_hsmmc_resume(struct device *dev)
 #define omap_hsmmc_resume	NULL
 #endif
 
+#ifdef CONFIG_PM_RUNTIME
 static int omap_hsmmc_runtime_suspend(struct device *dev)
 {
 	struct omap_hsmmc_host *host;
@@ -2264,6 +2264,10 @@ static int omap_hsmmc_runtime_resume(struct device *dev)
 
 	return 0;
 }
+#else
+#define omap_hsmmc_runtime_suspend	NULL
+#define omap_hsmmc_runtime_resume	NULL
+#endif
 
 static struct dev_pm_ops omap_hsmmc_dev_pm_ops = {
 	.suspend	= omap_hsmmc_suspend,
-- 
1.7.10.4

[PATCH v13 2/7] mmc: omap_hsmmc: Enable SDIO interrupt

[Andreas Fenkart]

There have been various patches floating around for enabling
the SDIO IRQ for hsmmc, but none of them ever got merged.

Probably the reason for not merging the SDIO interrupt patches
has been the lack of wake-up path for SDIO on some omaps that
has also needed remuxing the SDIO DAT1 line to a GPIO making
the patches complex.

This patch adds the minimal SDIO IRQ support to hsmmc for
omaps that do have the wake-up path. For those omaps, the
DAT1 line need to have the wake-up enable bit set, and the
wake-up interrupt is the same as for the MMC controller.

This patch has been tested on am3730 es1.2 with mwifiex
connected to MMC3 with mwifiex waking to Ethernet traffic
from off-idle mode. Note that for omaps that do not have
the SDIO wake-up path, this patch will not work for idle
modes and further patches for remuxing DAT1 to GPIO are
needed.

Based on earlier patches [1][2] by David Vrabel
<david.vrabel@csr.com>, Steve Sakoman <steve@sakoman.com>

For now, only support SDIO interrupt if we are booted with
a separate wake-irq configued via device tree. This is
because omaps need the wake-irq for idle states, and some
omaps need special quirks. And we don't want to add new
legacy mux platform init code callbacks any longer as we
are moving to DT based booting anyways.

To use it, you need to specify the wake-irq using the
interrupts-extended property.

[1] http://www.sakoman.com/cgi-bin/gitweb.cgi?p=linux.git;a=commitdiff_plain;h=010810d22f6f49ac03da4ba384969432e0320453
[2] http://comments.gmane.org/gmane.linux.kernel.mmc/20446

Acked-by: Balaji T K <balajitk@ti.com>
Signed-off-by: Andreas Fenkart <afenkart@gmail.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>

diff --git a/Documentation/devicetree/bindings/mmc/ti-omap-hsmmc.txt b/Documentation/devicetree/bindings/mmc/ti-omap-hsmmc.txt
index ce80561..0233ba7 100644
--- a/Documentation/devicetree/bindings/mmc/ti-omap-hsmmc.txt
+++ b/Documentation/devicetree/bindings/mmc/ti-omap-hsmmc.txt
@@ -12,6 +12,7 @@ Required properties:
  Should be "ti,omap3-hsmmc", for OMAP3 controllers
  Should be "ti,omap3-pre-es3-hsmmc" for OMAP3 controllers pre ES3.0
  Should be "ti,omap4-hsmmc", for OMAP4 controllers
+ Should be "ti,am33xx-hsmmc", for AM335x controllers
 - ti,hwmods: Must be "mmc<n>", n is controller instance starting 1
 
 Optional properties:
diff --git a/drivers/mmc/host/omap_hsmmc.c b/drivers/mmc/host/omap_hsmmc.c
index c62d9dd..0125eea 100644
--- a/drivers/mmc/host/omap_hsmmc.c
+++ b/drivers/mmc/host/omap_hsmmc.c
@@ -29,6 +29,7 @@
 #include <linux/timer.h>
 #include <linux/clk.h>
 #include <linux/of.h>
+#include <linux/of_irq.h>
 #include <linux/of_gpio.h>
 #include <linux/of_device.h>
 #include <linux/omap-dma.h>
@@ -36,6 +37,7 @@
 #include <linux/mmc/core.h>
 #include <linux/mmc/mmc.h>
 #include <linux/io.h>
+#include <linux/irq.h>
 #include <linux/gpio.h>
 #include <linux/regulator/consumer.h>
 #include <linux/pinctrl/consumer.h>
@@ -106,6 +108,7 @@
 #define TC_EN			(1 << 1)
 #define BWR_EN			(1 << 4)
 #define BRR_EN			(1 << 5)
+#define CIRQ_EN			(1 << 8)
 #define ERR_EN			(1 << 15)
 #define CTO_EN			(1 << 16)
 #define CCRC_EN			(1 << 17)
@@ -140,7 +143,6 @@
 #define VDD_3V0			3000000		/* 300000 uV */
 #define VDD_165_195		(ffs(MMC_VDD_165_195) - 1)
 
-#define AUTO_CMD23		(1 << 1)	/* Auto CMD23 support */
 /*
  * One controller can have multiple slots, like on some omap boards using
  * omap.c controller driver. Luckily this is not currently done on any known
@@ -200,6 +202,7 @@ struct omap_hsmmc_host {
 	int			slot_id;
 	int			response_busy;
 #ifdef CONFIG_PM
+	int			wake_irq;
 	int			context_loss;
 #endif
 	int			protect_card;
@@ -208,6 +211,9 @@ struct omap_hsmmc_host {
 	int			req_in_progress;
 	unsigned long		clk_rate;
 	unsigned int		flags;
+#define AUTO_CMD23		(1 << 0)        /* Auto CMD23 support */
+#define HSMMC_SDIO_IRQ_ENABLED	(1 << 1)        /* SDIO irq enabled */
+#define HSMMC_WAKE_IRQ_ENABLED	(1 << 2)
 	struct omap_hsmmc_next	next_data;
 	struct	omap_mmc_platform_data	*pdata;
 };
@@ -512,27 +518,40 @@ static void omap_hsmmc_stop_clock(struct omap_hsmmc_host *host)
 static void omap_hsmmc_enable_irq(struct omap_hsmmc_host *host,
 				  struct mmc_command *cmd)
 {
-	unsigned int irq_mask;
+	u32 irq_mask = INT_EN_MASK;
+	unsigned long flags;
 
 	if (host->use_dma)
-		irq_mask = INT_EN_MASK & ~(BRR_EN | BWR_EN);
-	else
-		irq_mask = INT_EN_MASK;
+		irq_mask &= ~(BRR_EN | BWR_EN);
 
 	/* Disable timeout for erases */
 	if (cmd->opcode == MMC_ERASE)
 		irq_mask &= ~DTO_EN;
 
+	spin_lock_irqsave(&host->irq_lock, flags);
 	OMAP_HSMMC_WRITE(host->base, STAT, STAT_CLEAR);
 	OMAP_HSMMC_WRITE(host->base, ISE, irq_mask);
+
+	/* latch pending CIRQ, but don't signal MMC core */
+	if (host->flags & HSMMC_SDIO_IRQ_ENABLED)
+		irq_mask |= CIRQ_EN;
 	OMAP_HSMMC_WRITE(host->base, IE, irq_mask);
+	spin_unlock_irqrestore(&host->irq_lock, flags);
 }
 
 static void omap_hsmmc_disable_irq(struct omap_hsmmc_host *host)
 {
-	OMAP_HSMMC_WRITE(host->base, ISE, 0);
-	OMAP_HSMMC_WRITE(host->base, IE, 0);
+	u32 irq_mask = 0;
+	unsigned long flags;
+
+	spin_lock_irqsave(&host->irq_lock, flags);
+	/* no transfer running but need to keep cirq if enabled */
+	if (host->flags & HSMMC_SDIO_IRQ_ENABLED)
+		irq_mask |= CIRQ_EN;
+	OMAP_HSMMC_WRITE(host->base, ISE, irq_mask);
+	OMAP_HSMMC_WRITE(host->base, IE, irq_mask);
 	OMAP_HSMMC_WRITE(host->base, STAT, STAT_CLEAR);
+	spin_unlock_irqrestore(&host->irq_lock, flags);
 }
 
 /* Calculate divisor for the given clock frequency */
@@ -683,7 +702,9 @@ static int omap_hsmmc_context_restore(struct omap_hsmmc_host *host)
 		&& time_before(jiffies, timeout))
 		;
 
-	omap_hsmmc_disable_irq(host);
+	OMAP_HSMMC_WRITE(host->base, ISE, 0);
+	OMAP_HSMMC_WRITE(host->base, IE, 0);
+	OMAP_HSMMC_WRITE(host->base, STAT, STAT_CLEAR);
 
 	/* Do not initialize card-specific things if the power is off */
 	if (host->power_mode == MMC_POWER_OFF)
@@ -1113,8 +1134,12 @@ static irqreturn_t omap_hsmmc_irq(int irq, void *dev_id)
 	int status;
 
 	status = OMAP_HSMMC_READ(host->base, STAT);
-	while (status & INT_EN_MASK && host->req_in_progress) {
-		omap_hsmmc_do_irq(host, status);
+	while (status & (INT_EN_MASK | CIRQ_EN)) {
+		if (host->req_in_progress)
+			omap_hsmmc_do_irq(host, status);
+
+		if (status & CIRQ_EN)
+			mmc_signal_sdio_irq(host->mmc);
 
 		/* Flush posted write */
 		status = OMAP_HSMMC_READ(host->base, STAT);
@@ -1123,6 +1148,24 @@ static irqreturn_t omap_hsmmc_irq(int irq, void *dev_id)
 	return IRQ_HANDLED;
 }
 
+#ifdef CONFIG_PM
+static irqreturn_t omap_hsmmc_wake_irq(int irq, void *dev_id)
+{
+	struct omap_hsmmc_host *host = dev_id;
+
+	/* cirq is level triggered, disable to avoid infinite loop */
+	spin_lock(&host->irq_lock);
+	if (host->flags & HSMMC_WAKE_IRQ_ENABLED) {
+		disable_irq_nosync(host->wake_irq);
+		host->flags &= ~HSMMC_WAKE_IRQ_ENABLED;
+	}
+	spin_unlock(&host->irq_lock);
+	pm_request_resume(host->dev); /* no use counter */
+
+	return IRQ_HANDLED;
+}
+#endif
+
 static void set_sd_bus_power(struct omap_hsmmc_host *host)
 {
 	unsigned long i;
@@ -1634,6 +1677,84 @@ static void omap_hsmmc_init_card(struct mmc_host *mmc, struct mmc_card *card)
 		mmc_slot(host).init_card(card);
 }
 
+static void omap_hsmmc_enable_sdio_irq(struct mmc_host *mmc, int enable)
+{
+	struct omap_hsmmc_host *host = mmc_priv(mmc);
+	u32 irq_mask;
+	unsigned long flags;
+
+	spin_lock_irqsave(&host->irq_lock, flags);
+
+	irq_mask = OMAP_HSMMC_READ(host->base, ISE);
+	if (enable) {
+		host->flags |= HSMMC_SDIO_IRQ_ENABLED;
+		irq_mask |= CIRQ_EN;
+	} else {
+		host->flags &= ~HSMMC_SDIO_IRQ_ENABLED;
+		irq_mask &= ~CIRQ_EN;
+	}
+	OMAP_HSMMC_WRITE(host->base, IE, irq_mask);
+
+	/*
+	 * if enable, piggy back detection on current request
+	 * but always disable immediately
+	 */
+	if (!host->req_in_progress || !enable)
+		OMAP_HSMMC_WRITE(host->base, ISE, irq_mask);
+
+	/* flush posted write */
+	OMAP_HSMMC_READ(host->base, IE);
+
+	spin_unlock_irqrestore(&host->irq_lock, flags);
+}
+
+#ifdef CONFIG_PM
+static int omap_hsmmc_configure_wake_irq(struct omap_hsmmc_host *host)
+{
+	struct mmc_host *mmc = host->mmc;
+	int ret;
+
+	/*
+	 * For omaps with wake-up path, wakeirq will be irq from pinctrl and
+	 * for other omaps, wakeirq will be from GPIO (dat line remuxed to
+	 * gpio). wakeirq is needed to detect sdio irq in runtime suspend state
+	 * with functional clock disabled.
+	 */
+	if (!host->dev->of_node || !host->wake_irq)
+		return -ENODEV;
+
+	/* Prevent auto-enabling of IRQ */
+	irq_set_status_flags(host->wake_irq, IRQ_NOAUTOEN);
+	ret = devm_request_irq(host->dev, host->wake_irq, omap_hsmmc_wake_irq,
+			       IRQF_TRIGGER_LOW | IRQF_ONESHOT,
+			       mmc_hostname(mmc), host);
+	if (ret) {
+		dev_err(mmc_dev(host->mmc), "Unable to request wake IRQ\n");
+		goto err;
+	}
+
+	/*
+	 * Some omaps don't have wake-up path from deeper idle states
+	 * and need to remux SDIO DAT1 to GPIO for wake-up from idle.
+	 */
+	if (host->pdata->controller_flags & OMAP_HSMMC_SWAKEUP_MISSING) {
+		ret = -ENODEV;
+		devm_free_irq(host->dev, host->wake_irq, host);
+		goto err;
+	}
+
+	return 0;
+
+err:
+	dev_warn(host->dev, "no SDIO IRQ support, falling back to polling\n");
+	host->wake_irq = 0;
+	return ret;
+}
+#else
+/* without suspend no wakeup needed */
+#define omap_hsmmc_configure_wake_irq(x)  (0)
+#endif
+
 static void omap_hsmmc_conf_bus_power(struct omap_hsmmc_host *host)
 {
 	u32 hctl, capa, value;
@@ -1686,7 +1807,7 @@ static const struct mmc_host_ops omap_hsmmc_ops = {
 	.get_cd = omap_hsmmc_get_cd,
 	.get_ro = omap_hsmmc_get_ro,
 	.init_card = omap_hsmmc_init_card,
-	/* NYET -- enable_sdio_irq */
+	.enable_sdio_irq = omap_hsmmc_enable_sdio_irq,
 };
 
 #ifdef CONFIG_DEBUG_FS
@@ -1759,6 +1880,10 @@ static const struct omap_mmc_of_data omap3_pre_es3_mmc_of_data = {
 static const struct omap_mmc_of_data omap4_mmc_of_data = {
 	.reg_offset = 0x100,
 };
+static const struct omap_mmc_of_data am33xx_mmc_of_data = {
+	.reg_offset = 0x100,
+	.controller_flags = OMAP_HSMMC_SWAKEUP_MISSING,
+};
 
 static const struct of_device_id omap_mmc_of_match[] = {
 	{
@@ -1775,6 +1900,10 @@ static const struct of_device_id omap_mmc_of_match[] = {
 		.compatible = "ti,omap4-hsmmc",
 		.data = &omap4_mmc_of_data,
 	},
+	{
+		.compatible = "ti,am33xx-hsmmc",
+		.data = &am33xx_mmc_of_data,
+	},
 	{},
 };
 MODULE_DEVICE_TABLE(of, omap_mmc_of_match);
@@ -1910,6 +2039,11 @@ static int omap_hsmmc_probe(struct platform_device *pdev)
 
 	platform_set_drvdata(pdev, host);
 
+#ifdef CONFIG_PM
+	if (pdev->dev.of_node)
+		host->wake_irq = irq_of_parse_and_map(pdev->dev.of_node, 1);
+#endif
+
 	mmc->ops	= &omap_hsmmc_ops;
 
 	mmc->f_min = OMAP_MMC_MIN_CLOCK;
@@ -2074,6 +2208,18 @@ static int omap_hsmmc_probe(struct platform_device *pdev)
 		dev_warn(&pdev->dev,
 			"pins are not configured from the driver\n");
 
+	/*
+	 * For now, only support SDIO interrupt if we have a separate
+	 * wake-up interrupt configured from device tree. This is because
+	 * the wake-up interrupt is needed for idle state and some
+	 * platforms need special quirks. And we don't want to add new
+	 * legacy mux platform init code callbacks any longer as we
+	 * are moving to DT based booting anyways.
+	 */
+	ret = omap_hsmmc_configure_wake_irq(host);
+	if (!ret)
+		mmc->caps |= MMC_CAP_SDIO_IRQ;
+
 	omap_hsmmc_protect_card(host);
 
 	mmc_add_host(mmc);
@@ -2200,11 +2346,18 @@ static int omap_hsmmc_suspend(struct device *dev)
 	pm_runtime_get_sync(host->dev);
 
 	if (!(host->mmc->pm_flags & MMC_PM_KEEP_POWER)) {
-		omap_hsmmc_disable_irq(host);
+		OMAP_HSMMC_WRITE(host->base, ISE, 0);
+		OMAP_HSMMC_WRITE(host->base, IE, 0);
+		OMAP_HSMMC_WRITE(host->base, STAT, STAT_CLEAR);
 		OMAP_HSMMC_WRITE(host->base, HCTL,
 				OMAP_HSMMC_READ(host->base, HCTL) & ~SDBP);
 	}
 
+	/* do not wake up due to sdio irq */
+	if ((host->mmc->caps & MMC_CAP_SDIO_IRQ) &&
+	    !(host->mmc->pm_flags & MMC_PM_WAKE_SDIO_IRQ))
+		disable_irq(host->wake_irq);
+
 	if (host->dbclk)
 		clk_disable_unprepare(host->dbclk);
 
@@ -2230,6 +2383,10 @@ static int omap_hsmmc_resume(struct device *dev)
 
 	omap_hsmmc_protect_card(host);
 
+	if ((host->mmc->caps & MMC_CAP_SDIO_IRQ) &&
+	    !(host->mmc->pm_flags & MMC_PM_WAKE_SDIO_IRQ))
+		enable_irq(host->wake_irq);
+
 	pm_runtime_mark_last_busy(host->dev);
 	pm_runtime_put_autosuspend(host->dev);
 	return 0;
@@ -2246,22 +2403,51 @@ static int omap_hsmmc_resume(struct device *dev)
 static int omap_hsmmc_runtime_suspend(struct device *dev)
 {
 	struct omap_hsmmc_host *host;
+	unsigned long flags;
 
 	host = platform_get_drvdata(to_platform_device(dev));
 	omap_hsmmc_context_save(host);
 	dev_dbg(dev, "disabled\n");
 
+	spin_lock_irqsave(&host->irq_lock, flags);
+	if ((host->mmc->caps & MMC_CAP_SDIO_IRQ) &&
+	    (host->flags & HSMMC_SDIO_IRQ_ENABLED)) {
+		/* disable sdio irq handling to prevent race */
+		OMAP_HSMMC_WRITE(host->base, ISE, 0);
+		OMAP_HSMMC_WRITE(host->base, IE, 0);
+		OMAP_HSMMC_WRITE(host->base, STAT, STAT_CLEAR);
+
+		WARN_ON(host->flags & HSMMC_WAKE_IRQ_ENABLED);
+		enable_irq(host->wake_irq);
+		host->flags |= HSMMC_WAKE_IRQ_ENABLED;
+	}
+	spin_unlock_irqrestore(&host->irq_lock, flags);
 	return 0;
 }
 
 static int omap_hsmmc_runtime_resume(struct device *dev)
 {
 	struct omap_hsmmc_host *host;
+	unsigned long flags;
 
 	host = platform_get_drvdata(to_platform_device(dev));
 	omap_hsmmc_context_restore(host);
 	dev_dbg(dev, "enabled\n");
 
+	spin_lock_irqsave(&host->irq_lock, flags);
+	if ((host->mmc->caps & MMC_CAP_SDIO_IRQ) &&
+	    (host->flags & HSMMC_SDIO_IRQ_ENABLED)) {
+		/* sdio irq flag can't change while in runtime suspend */
+		if (host->flags & HSMMC_WAKE_IRQ_ENABLED) {
+			disable_irq_nosync(host->wake_irq);
+			host->flags &= ~HSMMC_WAKE_IRQ_ENABLED;
+		}
+
+		OMAP_HSMMC_WRITE(host->base, STAT, STAT_CLEAR);
+		OMAP_HSMMC_WRITE(host->base, ISE, CIRQ_EN);
+		OMAP_HSMMC_WRITE(host->base, IE, CIRQ_EN);
+	}
+	spin_unlock_irqrestore(&host->irq_lock, flags);
 	return 0;
 }
 #else
diff --git a/include/linux/platform_data/mmc-omap.h b/include/linux/platform_data/mmc-omap.h
index 2bf1b30..51e70cf 100644
--- a/include/linux/platform_data/mmc-omap.h
+++ b/include/linux/platform_data/mmc-omap.h
@@ -28,6 +28,7 @@
  */
 #define OMAP_HSMMC_SUPPORTS_DUAL_VOLT		BIT(0)
 #define OMAP_HSMMC_BROKEN_MULTIBLOCK_READ	BIT(1)
+#define OMAP_HSMMC_SWAKEUP_MISSING		BIT(2)
 
 struct mmc_card;
 
-- 
1.7.10.4

[PATCH v13 3/7] mmc: omap_hsmmc: Extend debugfs by SDIO IRQ handling, runtime state

[Andreas Fenkart]

Add SDIO IRQ entries to debugfs entry. Note that PSTATE shows current
state of data lines, incl. SDIO IRQ pending

Acked-by: Balaji T K <balajitk@ti.com>
Signed-off-by: Andreas Fenkart <afenkart@gmail.com>

diff --git a/drivers/mmc/host/omap_hsmmc.c b/drivers/mmc/host/omap_hsmmc.c
index 0125eea..cfd2bfb 100644
--- a/drivers/mmc/host/omap_hsmmc.c
+++ b/drivers/mmc/host/omap_hsmmc.c
@@ -56,6 +56,7 @@
 #define OMAP_HSMMC_RSP54	0x0118
 #define OMAP_HSMMC_RSP76	0x011C
 #define OMAP_HSMMC_DATA		0x0120
+#define OMAP_HSMMC_PSTATE	0x0124
 #define OMAP_HSMMC_HCTL		0x0128
 #define OMAP_HSMMC_SYSCTL	0x012C
 #define OMAP_HSMMC_STAT		0x0130
@@ -1816,10 +1817,23 @@ static int omap_hsmmc_regs_show(struct seq_file *s, void *data)
 {
 	struct mmc_host *mmc = s->private;
 	struct omap_hsmmc_host *host = mmc_priv(mmc);
+#ifdef CONFIG_PM
+	bool suspended;
+#endif
 
 	seq_printf(s, "mmc%d:\n", mmc->index);
+	seq_printf(s, "sdio irq mode\t%s\n",
+		   (mmc->caps & MMC_CAP_SDIO_IRQ) ? "interrupt" : "polling");
+
+	if (mmc->caps & MMC_CAP_SDIO_IRQ) {
+		seq_printf(s, "sdio irq \t%s\n",
+			   (host->flags & HSMMC_SDIO_IRQ_ENABLED) ?  "enabled"
+			   : "disabled");
+	}
 
 #ifdef CONFIG_PM
+	suspended = host->dev->power.runtime_status != RPM_ACTIVE;
+	seq_printf(s, "runtime state\t%s\n", (suspended ? "idle" : "active"));
 	seq_printf(s, "ctx_loss:\t%d\n", host->context_loss);
 #endif
 
@@ -1827,6 +1841,8 @@ static int omap_hsmmc_regs_show(struct seq_file *s, void *data)
 	seq_puts(s, "\nregs:\n");
 	seq_printf(s, "CON:\t\t0x%08x\n",
 			OMAP_HSMMC_READ(host->base, CON));
+	seq_printf(s, "PSTATE:\t\t0x%08x\n",
+		   OMAP_HSMMC_READ(host->base, PSTATE));
 	seq_printf(s, "HCTL:\t\t0x%08x\n",
 			OMAP_HSMMC_READ(host->base, HCTL));
 	seq_printf(s, "SYSCTL:\t\t0x%08x\n",
-- 
1.7.10.4

[PATCH v13 4/7] mmc: omap_hsmmc: enable wakeup event for sdio OMAP4

[Andreas Fenkart]

To detect sdio irqs properly without spurious events,
OMAP4 needs IWE in CON and CTPL, CLKEXTFREE in HCTL to be set

Tested-by: Andreas Fenkart <afenkart@gmail.com>
Signed-off-by: Balaji T K <balajitk@ti.com>

diff --git a/drivers/mmc/host/omap_hsmmc.c b/drivers/mmc/host/omap_hsmmc.c
index cfd2bfb..dfc593e 100644
--- a/drivers/mmc/host/omap_hsmmc.c
+++ b/drivers/mmc/host/omap_hsmmc.c
@@ -94,7 +94,10 @@
 #define BCE			(1 << 1)
 #define FOUR_BIT		(1 << 1)
 #define HSPE			(1 << 2)
+#define IWE			(1 << 24)
 #define DDR			(1 << 19)
+#define CLKEXTFREE		(1 << 16)
+#define CTPL			(1 << 11)
 #define DW8			(1 << 5)
 #define OD			0x1
 #define STAT_CLEAR		0xFFFFFFFF
@@ -689,6 +692,9 @@ static int omap_hsmmc_context_restore(struct omap_hsmmc_host *host)
 		capa = VS18;
 	}
 
+	if (host->mmc->caps & MMC_CAP_SDIO_IRQ)
+		hctl |= IWE;
+
 	OMAP_HSMMC_WRITE(host->base, HCTL,
 			OMAP_HSMMC_READ(host->base, HCTL) | hctl);
 
@@ -1681,19 +1687,23 @@ static void omap_hsmmc_init_card(struct mmc_host *mmc, struct mmc_card *card)
 static void omap_hsmmc_enable_sdio_irq(struct mmc_host *mmc, int enable)
 {
 	struct omap_hsmmc_host *host = mmc_priv(mmc);
-	u32 irq_mask;
+	u32 irq_mask, con;
 	unsigned long flags;
 
 	spin_lock_irqsave(&host->irq_lock, flags);
 
+	con = OMAP_HSMMC_READ(host->base, CON);
 	irq_mask = OMAP_HSMMC_READ(host->base, ISE);
 	if (enable) {
 		host->flags |= HSMMC_SDIO_IRQ_ENABLED;
 		irq_mask |= CIRQ_EN;
+		con |= CTPL | CLKEXTFREE;
 	} else {
 		host->flags &= ~HSMMC_SDIO_IRQ_ENABLED;
 		irq_mask &= ~CIRQ_EN;
+		con &= ~(CTPL | CLKEXTFREE);
 	}
+	OMAP_HSMMC_WRITE(host->base, CON, con);
 	OMAP_HSMMC_WRITE(host->base, IE, irq_mask);
 
 	/*
@@ -1744,6 +1754,8 @@ static int omap_hsmmc_configure_wake_irq(struct omap_hsmmc_host *host)
 		goto err;
 	}
 
+	OMAP_HSMMC_WRITE(host->base, HCTL,
+			 OMAP_HSMMC_READ(host->base, HCTL) | IWE);
 	return 0;
 
 err:
-- 
1.7.10.4

[PATCH v13 5/7] mmc: omap_hsmmc: abort runtime suspend if pending sdio irq detected

[Andreas Fenkart]

On multicores, an sdio irq handler could be running in parallel to
runtime suspend. In the worst case it could be waiting for the spinlock
held by the runtime suspend. When runtime suspend is complete and the
functional clock (fclk) turned off, the irq handler will continue and
cause a SIGBUS on the first register access.

Acked-by: Balaji T K <balajitk@ti.com>
Signed-off-by: Andreas Fenkart <afenkart@gmail.com>

diff --git a/drivers/mmc/host/omap_hsmmc.c b/drivers/mmc/host/omap_hsmmc.c
index dfc593e..aafef29 100644
--- a/drivers/mmc/host/omap_hsmmc.c
+++ b/drivers/mmc/host/omap_hsmmc.c
@@ -107,6 +107,9 @@
 #define SRD			(1 << 26)
 #define SOFTRESET		(1 << 1)
 
+/* PSTATE */
+#define DLEV_DAT(x)		(1 << (20 + (x)))
+
 /* Interrupt masks for IE and ISE register */
 #define CC_EN			(1 << 0)
 #define TC_EN			(1 << 1)
@@ -2432,6 +2435,7 @@ static int omap_hsmmc_runtime_suspend(struct device *dev)
 {
 	struct omap_hsmmc_host *host;
 	unsigned long flags;
+	int ret = 0;
 
 	host = platform_get_drvdata(to_platform_device(dev));
 	omap_hsmmc_context_save(host);
@@ -2443,14 +2447,29 @@ static int omap_hsmmc_runtime_suspend(struct device *dev)
 		/* disable sdio irq handling to prevent race */
 		OMAP_HSMMC_WRITE(host->base, ISE, 0);
 		OMAP_HSMMC_WRITE(host->base, IE, 0);
-		OMAP_HSMMC_WRITE(host->base, STAT, STAT_CLEAR);
+
+		if (!(OMAP_HSMMC_READ(host->base, PSTATE) & DLEV_DAT(1))) {
+			/*
+			 * dat1 line low, pending sdio irq
+			 * race condition: possible irq handler running on
+			 * multi-core, abort
+			 */
+			dev_dbg(dev, "pending sdio irq, abort suspend\n");
+			OMAP_HSMMC_WRITE(host->base, STAT, STAT_CLEAR);
+			OMAP_HSMMC_WRITE(host->base, ISE, CIRQ_EN);
+			OMAP_HSMMC_WRITE(host->base, IE, CIRQ_EN);
+			pm_runtime_mark_last_busy(dev);
+			ret = -EBUSY;
+			goto abort;
+		}
 
 		WARN_ON(host->flags & HSMMC_WAKE_IRQ_ENABLED);
 		enable_irq(host->wake_irq);
 		host->flags |= HSMMC_WAKE_IRQ_ENABLED;
 	}
+abort:
 	spin_unlock_irqrestore(&host->irq_lock, flags);
-	return 0;
+	return ret;
 }
 
 static int omap_hsmmc_runtime_resume(struct device *dev)
-- 
1.7.10.4

[PATCH v13 6/7] mmc: omap_hsmmc: switch default/idle pinctrl states in runtime hooks

[Andreas Fenkart]

These are predefined states of the driver model. When not present,
as if not set in the device tree, they become no-ops.
Explicitly selecting the default state is not needed since the
device core layer sets pin mux to "default" state before probe.
This is not the simplest implementation, on AM335x at least, we could
switch to idle at any point in the suspend hook, only the default state
needs to be set before writing to the irq registers or an IRQ might get
lost.

Acked-by: Balaji T K <balajitk@ti.com>
Signed-off-by: Andreas Fenkart <afenkart@gmail.com>

diff --git a/drivers/mmc/host/omap_hsmmc.c b/drivers/mmc/host/omap_hsmmc.c
index aafef29..760b0ac 100644
--- a/drivers/mmc/host/omap_hsmmc.c
+++ b/drivers/mmc/host/omap_hsmmc.c
@@ -2008,7 +2008,6 @@ static int omap_hsmmc_probe(struct platform_device *pdev)
 	const struct of_device_id *match;
 	dma_cap_mask_t mask;
 	unsigned tx_req, rx_req;
-	struct pinctrl *pinctrl;
 	const struct omap_mmc_of_data *data;
 
 	match = of_match_device(of_match_ptr(omap_mmc_of_match), &pdev->dev);
@@ -2234,11 +2233,6 @@ static int omap_hsmmc_probe(struct platform_device *pdev)
 
 	omap_hsmmc_disable_irq(host);
 
-	pinctrl = devm_pinctrl_get_select_default(&pdev->dev);
-	if (IS_ERR(pinctrl))
-		dev_warn(&pdev->dev,
-			"pins are not configured from the driver\n");
-
 	/*
 	 * For now, only support SDIO interrupt if we have a separate
 	 * wake-up interrupt configured from device tree. This is because
@@ -2463,10 +2457,15 @@ static int omap_hsmmc_runtime_suspend(struct device *dev)
 			goto abort;
 		}
 
+		pinctrl_pm_select_idle_state(dev);
+
 		WARN_ON(host->flags & HSMMC_WAKE_IRQ_ENABLED);
 		enable_irq(host->wake_irq);
 		host->flags |= HSMMC_WAKE_IRQ_ENABLED;
+	} else {
+		pinctrl_pm_select_idle_state(dev);
 	}
+
 abort:
 	spin_unlock_irqrestore(&host->irq_lock, flags);
 	return ret;
@@ -2490,9 +2489,14 @@ static int omap_hsmmc_runtime_resume(struct device *dev)
 			host->flags &= ~HSMMC_WAKE_IRQ_ENABLED;
 		}
 
+		pinctrl_pm_select_default_state(host->dev);
+
+		/* irq lost, if pinmux incorrect */
 		OMAP_HSMMC_WRITE(host->base, STAT, STAT_CLEAR);
 		OMAP_HSMMC_WRITE(host->base, ISE, CIRQ_EN);
 		OMAP_HSMMC_WRITE(host->base, IE, CIRQ_EN);
+	} else {
+		pinctrl_pm_select_default_state(host->dev);
 	}
 	spin_unlock_irqrestore(&host->irq_lock, flags);
 	return 0;
-- 
1.7.10.4

[PATCH v13 7/7] mmc: omap_hsmmc: Pin remux workaround to support SDIO interrupt on AM335x

[Andreas Fenkart]

The am335x can't detect pending cirq in PM runtime suspend.
This patch reconfigures dat1 as a GPIO before going to suspend.
SDIO interrupts are detected with the GPIO, the GPIO will only wake
the module from suspend, SDIO irq detection will still happen through the
IP block.

Idea of remuxing the pins by Tony Lindgren. Code contributions from
Tony Lindgren and Balaji T K <balajitk@ti.com>

Acked-by: Balaji T K <balajitk@ti.com>
Signed-off-by: Andreas Fenkart <afenkart@gmail.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>

diff --git a/Documentation/devicetree/bindings/mmc/ti-omap-hsmmc.txt b/Documentation/devicetree/bindings/mmc/ti-omap-hsmmc.txt
index 0233ba7..76bf087 100644
--- a/Documentation/devicetree/bindings/mmc/ti-omap-hsmmc.txt
+++ b/Documentation/devicetree/bindings/mmc/ti-omap-hsmmc.txt
@@ -57,3 +57,56 @@ Examples:
 			&edma 25>;
 		dma-names = "tx", "rx";
 	};
+
+[workaround for missing swakeup on am33xx]
+
+This SOC is missing the swakeup line, it will not detect SDIO irq
+while in suspend.
+
+                             ------
+                             | PRCM |
+                              ------
+                               ^ |
+                       swakeup | | fclk
+                               | v
+       ------                -------               -----
+      | card | -- CIRQ -->  | hsmmc | -- IRQ -->  | CPU |
+       ------                -------               -----
+
+In suspend the fclk is off and the module is disfunctional. Even register reads
+will fail. A small logic in the host will request fclk restore, when an
+external event is detected. Once the clock is restored, the host detects the
+event normally. Since am33xx doesn't have this line it never wakes from
+suspend.
+
+The workaround is to reconfigure the dat1 line as a GPIO upon suspend. To make
+this work, we need to set the named pinctrl states "default" and "idle".
+Prepare idle to remux dat1 as a gpio, and default to remux it back as sdio
+dat1. The MMC driver will then toggle between idle and default state during
+runtime.
+
+In summary:
+1. select matching 'compatible' section, see example below.
+2. specify pinctrl states "default" and "idle", "sleep" is optional.
+3. specify the gpio irq used for detecting sdio irq in suspend
+
+If configuration is incomplete, a warning message is emitted "falling back to
+polling". Also check the "sdio irq mode" in /sys/kernel/debug/mmc0/regs. Mind
+not every application needs SDIO irq, e.g. MMC cards.
+
+	mmc1: mmc@48060100 {
+		compatible = "ti,am33xx-hsmmc";
+		...
+		pinctrl-names = "default", "idle", "sleep"
+		pinctrl-0 = <&mmc1_pins>;
+		pinctrl-1 = <&mmc1_idle>;
+		pinctrl-2 = <&mmc1_sleep>;
+		...
+		interrupts-extended = <&intc 64 &gpio2 28 0>;
+	};
+
+	mmc1_idle : pinmux_cirq_pin {
+		pinctrl-single,pins = <
+		        0x0f8 0x3f      /* GPIO2_28 */
+		>;
+	};
diff --git a/drivers/mmc/host/omap_hsmmc.c b/drivers/mmc/host/omap_hsmmc.c
index 760b0ac..1238506 100644
--- a/drivers/mmc/host/omap_hsmmc.c
+++ b/drivers/mmc/host/omap_hsmmc.c
@@ -1752,15 +1752,25 @@ static int omap_hsmmc_configure_wake_irq(struct omap_hsmmc_host *host)
 	 * and need to remux SDIO DAT1 to GPIO for wake-up from idle.
 	 */
 	if (host->pdata->controller_flags & OMAP_HSMMC_SWAKEUP_MISSING) {
-		ret = -ENODEV;
-		devm_free_irq(host->dev, host->wake_irq, host);
-		goto err;
+		if (IS_ERR(host->dev->pins->default_state)) {
+			dev_info(host->dev, "missing default pinctrl state\n");
+			ret = -EINVAL;
+			goto err_free_irq;
+		}
+
+		if (IS_ERR(host->dev->pins->idle_state)) {
+			dev_info(host->dev, "missing idle pinctrl state\n");
+			ret = -EINVAL;
+			goto err_free_irq;
+		}
 	}
 
 	OMAP_HSMMC_WRITE(host->base, HCTL,
 			 OMAP_HSMMC_READ(host->base, HCTL) | IWE);
 	return 0;
 
+err_free_irq:
+	devm_free_irq(host->dev, host->wake_irq, host);
 err:
 	dev_warn(host->dev, "no SDIO IRQ support, falling back to polling\n");
 	host->wake_irq = 0;
-- 
1.7.10.4

Re: [PATCH v13 1/7] mmc: omap_hsmmc: install dummy pm runtime hooks if !CONFIG_PM_RUNTIME

[Balaji T K]

On Friday 23 May 2014 02:00 PM, Andreas Fenkart wrote:
> Signed-off-by: Andreas Fenkart <afenkart@gmail.com>
>
> diff --git a/drivers/mmc/host/omap_hsmmc.c b/drivers/mmc/host/omap_hsmmc.c
> index 272e0ee..c62d9dd 100644
> --- a/drivers/mmc/host/omap_hsmmc.c
> +++ b/drivers/mmc/host/omap_hsmmc.c
> @@ -199,7 +199,9 @@ struct omap_hsmmc_host {
>   	struct dma_chan		*rx_chan;
>   	int			slot_id;
>   	int			response_busy;
> +#ifdef CONFIG_PM
>   	int			context_loss;
> +#endif
>   	int			protect_card;
>   	int			reqs_blocked;
>   	int			use_reg;
> @@ -712,14 +714,8 @@ static void omap_hsmmc_context_save(struct omap_hsmmc_host *host)
>
>   #else
>
> -static int omap_hsmmc_context_restore(struct omap_hsmmc_host *host)
> -{
> -	return 0;
> -}
> -
> -static void omap_hsmmc_context_save(struct omap_hsmmc_host *host)
> -{
> -}
> +#define omap_hsmmc_context_restore(host)
> +#define omap_hsmmc_context_save(host)
>
>   #endif
>
> @@ -1700,11 +1696,14 @@ static int omap_hsmmc_regs_show(struct seq_file *s, void *data)
>   	struct mmc_host *mmc = s->private;
>   	struct omap_hsmmc_host *host = mmc_priv(mmc);
>
> -	seq_printf(s, "mmc%d:\n ctx_loss:\t%d\n\nregs:\n",
> -			mmc->index, host->context_loss);
> +	seq_printf(s, "mmc%d:\n", mmc->index);
>
> -	pm_runtime_get_sync(host->dev);
> +#ifdef CONFIG_PM
> +	seq_printf(s, "ctx_loss:\t%d\n", host->context_loss);
> +#endif
>
> +	pm_runtime_get_sync(host->dev);
> +	seq_puts(s, "\nregs:\n");
>   	seq_printf(s, "CON:\t\t0x%08x\n",
>   			OMAP_HSMMC_READ(host->base, CON));
>   	seq_printf(s, "HCTL:\t\t0x%08x\n",
> @@ -2243,6 +2242,7 @@ static int omap_hsmmc_resume(struct device *dev)
>   #define omap_hsmmc_resume	NULL
>   #endif
>
> +#ifdef CONFIG_PM_RUNTIME

AFAIK, omap_hsmmc can build without these changes,
So, I think this patch is not needed.

Let me I know If it is not the case.

>   static int omap_hsmmc_runtime_suspend(struct device *dev)
>   {
>   	struct omap_hsmmc_host *host;
> @@ -2264,6 +2264,10 @@ static int omap_hsmmc_runtime_resume(struct device *dev)
>
>   	return 0;
>   }
> +#else
> +#define omap_hsmmc_runtime_suspend	NULL
> +#define omap_hsmmc_runtime_resume	NULL
> +#endif
>
>   static struct dev_pm_ops omap_hsmmc_dev_pm_ops = {
>   	.suspend	= omap_hsmmc_suspend,
>

Re: [PATCH v13 1/7] mmc: omap_hsmmc: install dummy pm runtime hooks if !CONFIG_PM_RUNTIME

[Andreas Fenkart]

2014-05-23 12:16 GMT+02:00 Balaji T K <balajitk@ti.com>:
> On Friday 23 May 2014 02:00 PM, Andreas Fenkart wrote:
>>
>>
>> +#ifdef CONFIG_PM_RUNTIME
>
>
> AFAIK, omap_hsmmc can build without these changes,
> So, I think this patch is not needed.
>
> Let me I know If it is not the case.

if do not guard suspend/resume then I have to add guards in patch 1/7:

> @@ -2200,11 +2346,18 @@ static int omap_hsmmc_suspend(struct device *dev)
>         pm_runtime_get_sync(host->dev);
>
>         if (!(host->mmc->pm_flags & MMC_PM_KEEP_POWER)) {
> -               omap_hsmmc_disable_irq(host);
> +               OMAP_HSMMC_WRITE(host->base, ISE, 0);
> +               OMAP_HSMMC_WRITE(host->base, IE, 0);
> +               OMAP_HSMMC_WRITE(host->base, STAT, STAT_CLEAR);
>                 OMAP_HSMMC_WRITE(host->base, HCTL,
>                                 OMAP_HSMMC_READ(host->base, HCTL) & ~SDBP);
>         }
>
> +       /* do not wake up due to sdio irq */
> +       if ((host->mmc->caps & MMC_CAP_SDIO_IRQ) &&
> +           !(host->mmc->pm_flags & MMC_PM_WAKE_SDIO_IRQ))
> +               disable_irq(host->wake_irq);

here

> +
>         if (host->dbclk)
>                 clk_disable_unprepare(host->dbclk);
>
> @@ -2230,6 +2383,10 @@ static int omap_hsmmc_resume(struct device *dev)
>
>         omap_hsmmc_protect_card(host);
>
> +       if ((host->mmc->caps & MMC_CAP_SDIO_IRQ) &&
> +           !(host->mmc->pm_flags & MMC_PM_WAKE_SDIO_IRQ))
> +               enable_irq(host->wake_irq);
> +
>         pm_runtime_mark_last_busy(host->dev);
>         pm_runtime_put_autosuspend(host->dev);
>         return 0;
> @@ -2246,22 +2403,51 @@ static int omap_hsmmc_resume(struct device *dev)
>  static int omap_hsmmc_runtime_suspend(struct device *dev)
>  {
>         struct omap_hsmmc_host *host;
> +       unsigned long flags;
>
>         host = platform_get_drvdata(to_platform_device(dev));
>         omap_hsmmc_context_save(host);
>         dev_dbg(dev, "disabled\n");
>
> +       spin_lock_irqsave(&host->irq_lock, flags);
> +       if ((host->mmc->caps & MMC_CAP_SDIO_IRQ) &&
> +           (host->flags & HSMMC_SDIO_IRQ_ENABLED)) {
> +               /* disable sdio irq handling to prevent race */
> +               OMAP_HSMMC_WRITE(host->base, ISE, 0);
> +               OMAP_HSMMC_WRITE(host->base, IE, 0);
> +               OMAP_HSMMC_WRITE(host->base, STAT, STAT_CLEAR);
> +
> +               WARN_ON(host->flags & HSMMC_WAKE_IRQ_ENABLED);
> +               enable_irq(host->wake_irq);

and here

> +               host->flags |= HSMMC_WAKE_IRQ_ENABLED;
> +       }
> +       spin_unlock_irqrestore(&host->irq_lock, flags);
>         return 0;
>  }
>

Re: [PATCH v13 3/7] mmc: omap_hsmmc: Extend debugfs by SDIO IRQ handling, runtime state

[Balaji T K]

On Friday 23 May 2014 02:00 PM, Andreas Fenkart wrote:
> Add SDIO IRQ entries to debugfs entry. Note that PSTATE shows current
> state of data lines, incl. SDIO IRQ pending
>
> Acked-by: Balaji T K <balajitk@ti.com>
> Signed-off-by: Andreas Fenkart <afenkart@gmail.com>
>
> diff --git a/drivers/mmc/host/omap_hsmmc.c b/drivers/mmc/host/omap_hsmmc.c
> index 0125eea..cfd2bfb 100644
> --- a/drivers/mmc/host/omap_hsmmc.c
> +++ b/drivers/mmc/host/omap_hsmmc.c
> @@ -56,6 +56,7 @@
>   #define OMAP_HSMMC_RSP54	0x0118
>   #define OMAP_HSMMC_RSP76	0x011C
>   #define OMAP_HSMMC_DATA		0x0120
> +#define OMAP_HSMMC_PSTATE	0x0124
>   #define OMAP_HSMMC_HCTL		0x0128
>   #define OMAP_HSMMC_SYSCTL	0x012C
>   #define OMAP_HSMMC_STAT		0x0130
> @@ -1816,10 +1817,23 @@ static int omap_hsmmc_regs_show(struct seq_file *s, void *data)
>   {
>   	struct mmc_host *mmc = s->private;
>   	struct omap_hsmmc_host *host = mmc_priv(mmc);
> +#ifdef CONFIG_PM
> +	bool suspended;
> +#endif
>
>   	seq_printf(s, "mmc%d:\n", mmc->index);
> +	seq_printf(s, "sdio irq mode\t%s\n",
> +		   (mmc->caps & MMC_CAP_SDIO_IRQ) ? "interrupt" : "polling");
> +
> +	if (mmc->caps & MMC_CAP_SDIO_IRQ) {
> +		seq_printf(s, "sdio irq \t%s\n",
> +			   (host->flags & HSMMC_SDIO_IRQ_ENABLED) ?  "enabled"
> +			   : "disabled");
> +	}
>
>   #ifdef CONFIG_PM

shouldn't this be CONFIG_PM_RUNTIME ?

> +	suspended = host->dev->power.runtime_status != RPM_ACTIVE;
> +	seq_printf(s, "runtime state\t%s\n", (suspended ? "idle" : "active"));

The whole check for runtime status (and check for CONFIG_PM..) can be removed,
since runtime status is available via sysfs

cat /sys/class/mmc_host/mmc<X>/device/power/runtime_status

>   	seq_printf(s, "ctx_loss:\t%d\n", host->context_loss);
>   #endif
>
> @@ -1827,6 +1841,8 @@ static int omap_hsmmc_regs_show(struct seq_file *s, void *data)
>   	seq_puts(s, "\nregs:\n");
>   	seq_printf(s, "CON:\t\t0x%08x\n",
>   			OMAP_HSMMC_READ(host->base, CON));
> +	seq_printf(s, "PSTATE:\t\t0x%08x\n",
> +		   OMAP_HSMMC_READ(host->base, PSTATE));
>   	seq_printf(s, "HCTL:\t\t0x%08x\n",
>   			OMAP_HSMMC_READ(host->base, HCTL));
>   	seq_printf(s, "SYSCTL:\t\t0x%08x\n",
>

Re: [PATCH v13 7/7] mmc: omap_hsmmc: Pin remux workaround to support SDIO interrupt on AM335x

[Balaji T K]

On Friday 23 May 2014 02:00 PM, Andreas Fenkart wrote:
> The am335x can't detect pending cirq in PM runtime suspend.
> This patch reconfigures dat1 as a GPIO before going to suspend.
> SDIO interrupts are detected with the GPIO, the GPIO will only wake
> the module from suspend, SDIO irq detection will still happen through the
> IP block.
>
> Idea of remuxing the pins by Tony Lindgren. Code contributions from
> Tony Lindgren and Balaji T K <balajitk@ti.com>
>
> Acked-by: Balaji T K <balajitk@ti.com>
> Signed-off-by: Andreas Fenkart <afenkart@gmail.com>
> Signed-off-by: Tony Lindgren <tony@atomide.com>
>
> diff --git a/Documentation/devicetree/bindings/mmc/ti-omap-hsmmc.txt b/Documentation/devicetree/bindings/mmc/ti-omap-hsmmc.txt
> index 0233ba7..76bf087 100644
> --- a/Documentation/devicetree/bindings/mmc/ti-omap-hsmmc.txt
> +++ b/Documentation/devicetree/bindings/mmc/ti-omap-hsmmc.txt
> @@ -57,3 +57,56 @@ Examples:
>   			&edma 25>;
>   		dma-names = "tx", "rx";
>   	};
> +
> +[workaround for missing swakeup on am33xx]
> +
> +This SOC is missing the swakeup line, it will not detect SDIO irq
> +while in suspend.
> +
> +                             ------
> +                             | PRCM |
> +                              ------
> +                               ^ |
> +                       swakeup | | fclk
> +                               | v
> +       ------                -------               -----
> +      | card | -- CIRQ -->  | hsmmc | -- IRQ -->  | CPU |
> +       ------                -------               -----
> +
> +In suspend the fclk is off and the module is disfunctional. Even register reads
> +will fail. A small logic in the host will request fclk restore, when an
> +external event is detected. Once the clock is restored, the host detects the
> +event normally. Since am33xx doesn't have this line it never wakes from
> +suspend.
> +
> +The workaround is to reconfigure the dat1 line as a GPIO upon suspend. To make
> +this work, we need to set the named pinctrl states "default" and "idle".
> +Prepare idle to remux dat1 as a gpio, and default to remux it back as sdio
> +dat1. The MMC driver will then toggle between idle and default state during
> +runtime.
> +
> +In summary:
> +1. select matching 'compatible' section, see example below.
> +2. specify pinctrl states "default" and "idle", "sleep" is optional.
> +3. specify the gpio irq used for detecting sdio irq in suspend
> +
> +If configuration is incomplete, a warning message is emitted "falling back to
> +polling". Also check the "sdio irq mode" in /sys/kernel/debug/mmc0/regs. Mind
> +not every application needs SDIO irq, e.g. MMC cards.
> +
> +	mmc1: mmc@48060100 {
> +		compatible = "ti,am33xx-hsmmc";
> +		...
> +		pinctrl-names = "default", "idle", "sleep"
> +		pinctrl-0 = <&mmc1_pins>;
> +		pinctrl-1 = <&mmc1_idle>;
> +		pinctrl-2 = <&mmc1_sleep>;
> +		...
> +		interrupts-extended = <&intc 64 &gpio2 28 0>;
> +	};
> +
> +	mmc1_idle : pinmux_cirq_pin {
> +		pinctrl-single,pins = <
> +		        0x0f8 0x3f      /* GPIO2_28 */
> +		>;
> +	};
> diff --git a/drivers/mmc/host/omap_hsmmc.c b/drivers/mmc/host/omap_hsmmc.c
> index 760b0ac..1238506 100644
> --- a/drivers/mmc/host/omap_hsmmc.c
> +++ b/drivers/mmc/host/omap_hsmmc.c
> @@ -1752,15 +1752,25 @@ static int omap_hsmmc_configure_wake_irq(struct omap_hsmmc_host *host)
>   	 * and need to remux SDIO DAT1 to GPIO for wake-up from idle.
>   	 */
>   	if (host->pdata->controller_flags & OMAP_HSMMC_SWAKEUP_MISSING) {
> -		ret = -ENODEV;
> -		devm_free_irq(host->dev, host->wake_irq, host);
> -		goto err;
> +		if (IS_ERR(host->dev->pins->default_state)) {

Rater than introducing #ifdef CONFIG_PM on multiple places,
I think things will simple, if pinctrl_lookup_state is used here
to avoid build error on !CONFIG_PM



> +			dev_info(host->dev, "missing default pinctrl state\n");
> +			ret = -EINVAL;
> +			goto err_free_irq;
> +		}
> +
> +		if (IS_ERR(host->dev->pins->idle_state)) {

same here.

> +			dev_info(host->dev, "missing idle pinctrl state\n");
> +			ret = -EINVAL;
> +			goto err_free_irq;
> +		}
>   	}
>
>   	OMAP_HSMMC_WRITE(host->base, HCTL,
>   			 OMAP_HSMMC_READ(host->base, HCTL) | IWE);
>   	return 0;
>
> +err_free_irq:
> +	devm_free_irq(host->dev, host->wake_irq, host);
>   err:
>   	dev_warn(host->dev, "no SDIO IRQ support, falling back to polling\n");
>   	host->wake_irq = 0;
>

Re: [PATCH v13 3/7] mmc: omap_hsmmc: Extend debugfs by SDIO IRQ handling, runtime state

[Tony Lindgren]

* Balaji T K <balajitk@ti.com> [140523 05:27]:
> On Friday 23 May 2014 02:00 PM, Andreas Fenkart wrote:
> >Add SDIO IRQ entries to debugfs entry. Note that PSTATE shows current
> >state of data lines, incl. SDIO IRQ pending
> >
> >Acked-by: Balaji T K <balajitk@ti.com>
> >Signed-off-by: Andreas Fenkart <afenkart@gmail.com>
> >
> >diff --git a/drivers/mmc/host/omap_hsmmc.c b/drivers/mmc/host/omap_hsmmc.c
> >index 0125eea..cfd2bfb 100644
> >--- a/drivers/mmc/host/omap_hsmmc.c
> >+++ b/drivers/mmc/host/omap_hsmmc.c
> >@@ -56,6 +56,7 @@
> >  #define OMAP_HSMMC_RSP54	0x0118
> >  #define OMAP_HSMMC_RSP76	0x011C
> >  #define OMAP_HSMMC_DATA		0x0120
> >+#define OMAP_HSMMC_PSTATE	0x0124
> >  #define OMAP_HSMMC_HCTL		0x0128
> >  #define OMAP_HSMMC_SYSCTL	0x012C
> >  #define OMAP_HSMMC_STAT		0x0130
> >@@ -1816,10 +1817,23 @@ static int omap_hsmmc_regs_show(struct seq_file *s, void *data)
> >  {
> >  	struct mmc_host *mmc = s->private;
> >  	struct omap_hsmmc_host *host = mmc_priv(mmc);
> >+#ifdef CONFIG_PM
> >+	bool suspended;
> >+#endif
> >
> >  	seq_printf(s, "mmc%d:\n", mmc->index);
> >+	seq_printf(s, "sdio irq mode\t%s\n",
> >+		   (mmc->caps & MMC_CAP_SDIO_IRQ) ? "interrupt" : "polling");
> >+
> >+	if (mmc->caps & MMC_CAP_SDIO_IRQ) {
> >+		seq_printf(s, "sdio irq \t%s\n",
> >+			   (host->flags & HSMMC_SDIO_IRQ_ENABLED) ?  "enabled"
> >+			   : "disabled");
> >+	}
> >
> >  #ifdef CONFIG_PM
> 
> shouldn't this be CONFIG_PM_RUNTIME ?
> 
> >+	suspended = host->dev->power.runtime_status != RPM_ACTIVE;
> >+	seq_printf(s, "runtime state\t%s\n", (suspended ? "idle" : "active"));
> 
> The whole check for runtime status (and check for CONFIG_PM..) can be removed,
> since runtime status is available via sysfs
> 
> cat /sys/class/mmc_host/mmc<X>/device/power/runtime_status
> 
> >  	seq_printf(s, "ctx_loss:\t%d\n", host->context_loss);
> >  #endif

Also CONFIG_SYSFS is a bool FYI.

Regards,

Tony