[PATCH v2 1/3] mmc: omap_hsmmc: Enable SDIO IRQ using a GPIO in idle mode.
Andreas Fenkart
andreas.fenkart at streamunlimited.com
Fri Apr 12 22:38:25 EST 2013
Without functional clock the omap_hsmmc module can't forward
SDIO IRQs to the system. This patch reconfigures dat1 line as a
gpio while the fclk is off. It uses regulare SDIO IRQ detection of
the module, while fclk is present.
Reviewed-by: Grant Likely <grant.likely at secretlab.ca>
Signed-off-by: Andreas Fenkart <andreas.fenkart at streamunlimited.com>
diff --git a/Documentation/devicetree/bindings/mmc/ti-omap-hsmmc.txt b/Documentation/devicetree/bindings/mmc/ti-omap-hsmmc.txt
index ed271fc..5a3df37 100644
--- a/Documentation/devicetree/bindings/mmc/ti-omap-hsmmc.txt
+++ b/Documentation/devicetree/bindings/mmc/ti-omap-hsmmc.txt
@@ -20,6 +20,29 @@ ti,dual-volt: boolean, supports dual voltage cards
ti,non-removable: non-removable slot (like eMMC)
ti,needs-special-reset: Requires a special softreset sequence
ti,needs-special-hs-handling: HSMMC IP needs special setting for handling High Speed
+ti,cirq-gpio: When omap_hsmmc module is suspended, its functional
+clock is turned off. Without fclk it can't forward SDIO IRQs to the
+system. For that to happen, it needs to tell the PRCM to restore
+its fclk, which is done through the swakeup line.
+
+ ------
+ | PRCM |
+ ------
+ | ^
+ fclk | | swakeup
+ v |
+ ------- ------
+ <-- IRQ -- | hsmmc | <-- CIRQ -- | card |
+ ------- ------
+
+The problem is, that on the AM335x family the swakeup line is
+missing, it has not been routed from the module to the PRCM.
+The way to work around this, is to reconfigure the dat1 line as a
+GPIO upon suspend. Beyond this option you also need to set named
+states "default" and "idle "in the .dts file for the pins, using
+pinctrl-single.c. The MMC driver will then then toggle between
+default and idle during the runtime.
+
Example:
mmc1: mmc at 0x4809c000 {
@@ -31,3 +54,22 @@ Example:
vmmc-supply = <&vmmc>; /* phandle to regulator node */
ti,non-removable;
};
+
+[am335x with with gpio for sdio irq]
+
+ mmc1_cirq_pin: pinmux_cirq_pin {
+ pinctrl-single,pins = <
+ 0x0f8 0x3f /* MMC0_DAT1 as GPIO2_28 */
+ >;
+ };
+
+ mmc1: mmc at 48060000 {
+ pinctrl-names = "default", "idle";
+ pinctrl-0 = <&mmc1_pins>;
+ pinctrl-1 = <&mmc1_cirq_pin>;
+ ti,cirq-gpio = <&gpio3 28 0>;
+ ti,non-removable;
+ bus-width = <4>;
+ vmmc-supply = <&ldo2_reg>;
+ vmmc_aux-supply = <&vmmc>;
+ };
diff --git a/drivers/mmc/host/omap_hsmmc.c b/drivers/mmc/host/omap_hsmmc.c
index 7d5b202..c52a0d1 100644
--- a/drivers/mmc/host/omap_hsmmc.c
+++ b/drivers/mmc/host/omap_hsmmc.c
@@ -22,6 +22,7 @@
#include <linux/dmaengine.h>
#include <linux/seq_file.h>
#include <linux/interrupt.h>
+#include <linux/irq.h>
#include <linux/delay.h>
#include <linux/dma-mapping.h>
#include <linux/platform_device.h>
@@ -103,6 +104,7 @@
#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)
@@ -206,10 +208,22 @@ struct omap_hsmmc_host {
int use_reg;
int req_in_progress;
struct omap_hsmmc_next next_data;
+ bool sdio_irq_en;
+ struct pinctrl *pinctrl;
+ struct pinctrl_state *active, *idle;
+ bool active_pinmux;
struct omap_mmc_platform_data *pdata;
};
+static irqreturn_t omap_hsmmc_cirq(int irq, void *dev_id)
+{
+ struct omap_hsmmc_host *host = dev_id;
+
+ mmc_signal_sdio_irq(host->mmc);
+ return IRQ_HANDLED;
+}
+
static int omap_hsmmc_card_detect(struct device *dev, int slot)
{
struct omap_hsmmc_host *host = dev_get_drvdata(dev);
@@ -444,10 +458,30 @@ static int omap_hsmmc_gpio_init(struct omap_mmc_platform_data *pdata)
} else
pdata->slots[0].gpio_wp = -EINVAL;
+ if (gpio_is_valid(pdata->slots[0].gpio_cirq)) {
+ pdata->slots[0].sdio_irq =
+ gpio_to_irq(pdata->slots[0].gpio_cirq);
+
+ ret = gpio_request(pdata->slots[0].gpio_cirq, "sdio_cirq");
+ if (ret)
+ goto err_free_ro;
+ ret = gpio_direction_input(pdata->slots[0].gpio_cirq);
+ if (ret)
+ goto err_free_cirq;
+
+ } else {
+ pdata->slots[0].gpio_cirq = -EINVAL;
+ }
+
+
return 0;
+err_free_cirq:
+ gpio_free(pdata->slots[0].gpio_cirq);
+err_free_ro:
+ if (gpio_is_valid(pdata->slots[0].gpio_wp))
err_free_wp:
- gpio_free(pdata->slots[0].gpio_wp);
+ gpio_free(pdata->slots[0].gpio_wp);
err_free_cd:
if (gpio_is_valid(pdata->slots[0].switch_pin))
err_free_sp:
@@ -461,6 +495,8 @@ static void omap_hsmmc_gpio_free(struct omap_mmc_platform_data *pdata)
gpio_free(pdata->slots[0].gpio_wp);
if (gpio_is_valid(pdata->slots[0].switch_pin))
gpio_free(pdata->slots[0].switch_pin);
+ if (gpio_is_valid(pdata->slots[0].gpio_cirq))
+ gpio_free(pdata->slots[0].gpio_cirq);
}
/*
@@ -486,27 +522,46 @@ 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 */
+ if (host->sdio_irq_en)
+ 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, need to signal cirq if */
+ if (host->sdio_irq_en)
+ 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 */
@@ -1080,8 +1135,12 @@ 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 */
OMAP_HSMMC_WRITE(host->base, STAT, status);
@@ -1597,6 +1656,51 @@ 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);
+
+ if (host->sdio_irq_en == enable) {
+ dev_dbg(host->dev, "en/disable:%d already set", enable);
+ spin_unlock_irqrestore(&host->irq_lock, flags);
+ return;
+ }
+
+ host->sdio_irq_en = (enable != 0) ? true : false;
+
+ if (host->active_pinmux) { /* register access fails without fclk */
+ irq_mask = OMAP_HSMMC_READ(host->base, ISE);
+ if (enable)
+ irq_mask |= CIRQ_EN;
+ else
+ irq_mask &= ~CIRQ_EN;
+ OMAP_HSMMC_WRITE(host->base, IE, irq_mask);
+
+ if (!host->req_in_progress)
+ OMAP_HSMMC_WRITE(host->base, ISE, irq_mask);
+
+ /*
+ * evtl. need to flush posted write
+ * OMAP_HSMMC_READ(host->base, IE);
+ */
+ }
+
+ if ((mmc_slot(host).sdio_irq)) {
+ if (enable) {
+ enable_irq(mmc_slot(host).sdio_irq);
+ } else {
+ /* _nosync, see mmc_signal_sdio_irq */
+ disable_irq_nosync(mmc_slot(host).sdio_irq);
+ }
+ }
+
+ spin_unlock_irqrestore(&host->irq_lock, flags);
+}
+
static void omap_hsmmc_conf_bus_power(struct omap_hsmmc_host *host)
{
u32 hctl, capa, value;
@@ -1649,7 +1753,7 @@ 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
@@ -1754,6 +1858,7 @@ static struct omap_mmc_platform_data *of_get_hsmmc_pdata(struct device *dev)
pdata->nr_slots = 1;
pdata->slots[0].switch_pin = of_get_named_gpio(np, "cd-gpios", 0);
pdata->slots[0].gpio_wp = of_get_named_gpio(np, "wp-gpios", 0);
+ pdata->slots[0].gpio_cirq = of_get_named_gpio(np, "ti,cirq-gpio", 0);
if (of_find_property(np, "ti,non-removable", NULL)) {
pdata->slots[0].nonremovable = true;
@@ -1794,7 +1899,6 @@ 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;
match = of_match_device(of_match_ptr(omap_mmc_of_match), &pdev->dev);
if (match) {
@@ -1845,6 +1949,8 @@ static int omap_hsmmc_probe(struct platform_device *pdev)
host->dma_ch = -1;
host->irq = irq;
host->slot_id = 0;
+ host->sdio_irq_en = false;
+ host->active_pinmux = true;
host->mapbase = res->start + pdata->reg_offset;
host->base = ioremap(host->mapbase, SZ_4K);
host->power_mode = MMC_POWER_OFF;
@@ -2014,12 +2120,61 @@ static int omap_hsmmc_probe(struct platform_device *pdev)
pdata->resume = omap_hsmmc_resume_cdirq;
}
+ if ((mmc_slot(host).sdio_irq)) {
+ /* prevent auto-enabling of IRQ */
+ irq_set_status_flags(mmc_slot(host).sdio_irq, IRQ_NOAUTOEN);
+ ret = request_irq(mmc_slot(host).sdio_irq, omap_hsmmc_cirq,
+ IRQF_TRIGGER_LOW | IRQF_ONESHOT,
+ mmc_hostname(mmc), host);
+ if (ret) {
+ dev_dbg(mmc_dev(host->mmc),
+ "Unable to grab MMC SDIO IRQ\n");
+ goto err_irq_sdio;
+ }
+
+ /*
+ * sdio_irq is managed with ref count
+ * - omap_hsmmc_enable_sdio_irq will +1/-1
+ * - pm_suspend/pm_resume will +1/-1
+ * only when sdio irq is enabled AND module will go to runtime
+ * suspend the ref count will drop to zero and the irq is
+ * effectively enabled. starting with ref count equal 2
+ */
+ disable_irq(mmc_slot(host).sdio_irq);
+ }
+
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");
+ host->pinctrl = devm_pinctrl_get(&pdev->dev);
+ if (IS_ERR(host->pinctrl)) {
+ ret = PTR_ERR(host->pinctrl);
+ goto err_pinctrl;
+ }
+
+ host->active = pinctrl_lookup_state(host->pinctrl,
+ PINCTRL_STATE_DEFAULT);
+ if (IS_ERR(host->active)) {
+ dev_warn(mmc_dev(host->mmc), "Unable to lookup active pinmux\n");
+ ret = PTR_ERR(host->active);
+ goto err_pinctrl_state;
+ }
+
+ if (mmc_slot(host).sdio_irq) {
+ host->idle = pinctrl_lookup_state(host->pinctrl,
+ PINCTRL_STATE_IDLE);
+ if (IS_ERR(host->idle)) {
+ dev_warn(mmc_dev(host->mmc), "Unable to lookup idle pinmux\n");
+ ret = PTR_ERR(host->idle);
+ goto err_pinctrl_state;
+ }
+ mmc->caps |= MMC_CAP_SDIO_IRQ;
+ }
+
+ ret = pinctrl_select_state(host->pinctrl, host->active);
+ if (ret < 0) {
+ dev_warn(mmc_dev(host->mmc), "Unable to select idle pinmux\n");
+ goto err_pinctrl_state;
+ }
omap_hsmmc_protect_card(host);
@@ -2045,6 +2200,12 @@ static int omap_hsmmc_probe(struct platform_device *pdev)
err_slot_name:
mmc_remove_host(mmc);
+err_pinctrl_state:
+ devm_pinctrl_put(host->pinctrl);
+err_pinctrl:
+ if ((mmc_slot(host).sdio_irq))
+ free_irq(mmc_slot(host).sdio_irq, host);
+err_irq_sdio:
free_irq(mmc_slot(host).card_detect_irq, host);
err_irq_cd:
if (host->use_reg)
@@ -2091,13 +2252,15 @@ static int omap_hsmmc_remove(struct platform_device *pdev)
if (host->pdata->cleanup)
host->pdata->cleanup(&pdev->dev);
free_irq(host->irq, host);
+ if ((mmc_slot(host).sdio_irq))
+ free_irq(mmc_slot(host).sdio_irq, host);
if (mmc_slot(host).card_detect_irq)
free_irq(mmc_slot(host).card_detect_irq, host);
-
if (host->tx_chan)
dma_release_channel(host->tx_chan);
if (host->rx_chan)
dma_release_channel(host->rx_chan);
+ devm_pinctrl_put(host->pinctrl);
pm_runtime_put_sync(host->dev);
pm_runtime_disable(host->dev);
@@ -2216,23 +2379,63 @@ 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;
+ int ret = 0;
host = platform_get_drvdata(to_platform_device(dev));
omap_hsmmc_context_save(host);
dev_dbg(dev, "disabled\n");
- return 0;
+ if (mmc_slot(host).sdio_irq && host->pinctrl) {
+ spin_lock_irqsave(&host->irq_lock, flags);
+ host->active_pinmux = false;
+ OMAP_HSMMC_WRITE(host->base, ISE, 0);
+ OMAP_HSMMC_WRITE(host->base, IE, 0);
+ OMAP_HSMMC_WRITE(host->base, STAT, STAT_CLEAR);
+ spin_unlock_irqrestore(&host->irq_lock, flags);
+
+ ret = pinctrl_select_state(host->pinctrl, host->idle);
+ if (ret < 0) {
+ dev_warn(mmc_dev(host->mmc), "Unable to select idle pinmux\n");
+ return ret;
+ }
+
+ enable_irq(mmc_slot(host).sdio_irq);
+ }
+
+ return ret;
}
static int omap_hsmmc_runtime_resume(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_restore(host);
dev_dbg(dev, "enabled\n");
- return 0;
+ if (mmc_slot(host).sdio_irq && host->pinctrl) {
+ disable_irq(mmc_slot(host).sdio_irq);
+
+ ret = pinctrl_select_state(host->pinctrl, host->active);
+ if (ret < 0) {
+ dev_warn(mmc_dev(host->mmc), "Unable to select active pinmux\n");
+ return ret;
+ }
+
+ spin_lock_irqsave(&host->irq_lock, flags);
+ host->active_pinmux = true;
+
+ if (host->sdio_irq_en) {
+ 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 ret;
}
static struct dev_pm_ops omap_hsmmc_dev_pm_ops = {
diff --git a/include/linux/platform_data/mmc-omap.h b/include/linux/platform_data/mmc-omap.h
index 2bf1b30..fd5fff5 100644
--- a/include/linux/platform_data/mmc-omap.h
+++ b/include/linux/platform_data/mmc-omap.h
@@ -115,6 +115,7 @@ struct omap_mmc_platform_data {
int switch_pin; /* gpio (card detect) */
int gpio_wp; /* gpio (write protect) */
+ int gpio_cirq; /* gpio (card irq) */
int (*set_bus_mode)(struct device *dev, int slot, int bus_mode);
int (*set_power)(struct device *dev, int slot,
@@ -145,6 +146,9 @@ struct omap_mmc_platform_data {
int card_detect_irq;
int (*card_detect)(struct device *dev, int slot);
+ /* SDIO IRQs */
+ int sdio_irq;
+
unsigned int ban_openended:1;
} slots[OMAP_MMC_MAX_SLOTS];
--
1.7.10.4
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