@@ -55,3 +55,53 @@ 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 1) the compatible
+section, 2) the named pinctrl states "default", "active" and
+"idle " and 3) the gpio detecting sdio irq in suspend, see
+example below. The MMC driver will then then toggle between
+active and idle during the runtime. If configuration is
+incomplete, log message is emitted "falling back to polling".
+Mind not every application needs SDIO irq, e.g. MMC cards
+Affected chips are am335x, probably others
+
+
+ mmc1: mmc@48060100 {
+ compatible = "ti,am33xx-hsmmc";
+ ...
+ interrupts-extended = <&intc 64 &gpio2 28 0>;
+ ...
+ pinctrl-names = "default", "active", "idle"
+ pinctrl-0 = <&mmc1_pins>;
+ pinctrl-1 = <&mmc1_pins>;
+ pinctrl-2 = <&mmc1_cirq_pin>;
+ ...
+ };
+
+ mmc1_cirq_pin: pinmux_cirq_pin {
+ pinctrl-single,pins = <
+ 0x0f8 0x3f /* GPIO2_28 */
+ >;
+ };
@@ -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>
@@ -206,6 +208,7 @@ struct omap_hsmmc_host {
u32 sysctl;
u32 capa;
int irq;
+ int gpio_sdio_irq;
int use_dma, dma_ch;
struct dma_chan *tx_chan;
struct dma_chan *rx_chan;
@@ -218,11 +221,32 @@ struct omap_hsmmc_host {
int req_in_progress;
int flags;
#define HSMMC_SDIO_IRQ_ENABLED (1 << 0) /* SDIO irq enabled */
+#define HSMMC_SWAKEUP_QUIRK (1 << 1)
+#define HSMMC_CIRQ_GPIO_ENABLED (1 << 2)
struct omap_hsmmc_next next_data;
+ struct pinctrl *pinctrl;
+ struct pinctrl_state *fixed, *active, *idle;
struct omap_mmc_platform_data *pdata;
};
+static irqreturn_t omap_hsmmc_cirq(int irq, void *dev_id)
+{
+ struct omap_hsmmc_host *host = dev_id;
+ unsigned long flags;
+
+ spin_lock_irqsave(&host->irq_lock, flags);
+ if (host->flags & HSMMC_CIRQ_GPIO_ENABLED) {
+ disable_irq_nosync(host->gpio_sdio_irq);
+ host->flags &= ~HSMMC_CIRQ_GPIO_ENABLED;
+ }
+ spin_unlock_irqrestore(&host->irq_lock, flags);
+
+ pm_request_resume(host->dev); /* no use counter */
+
+ return IRQ_HANDLED;
+}
+
static int omap_hsmmc_card_detect(struct device *dev, int slot)
{
struct omap_hsmmc_host *host = dev_get_drvdata(dev);
@@ -476,6 +500,67 @@ static void omap_hsmmc_gpio_free(struct omap_mmc_platform_data *pdata)
gpio_free(pdata->slots[0].switch_pin);
}
+static int omap_hsmmc_pin_init(struct omap_hsmmc_host *host)
+{
+ int ret;
+
+ host->pinctrl = devm_pinctrl_get(host->dev);
+ if (IS_ERR(host->pinctrl)) {
+ dev_dbg(host->dev, "no pinctrl handle\n");
+ ret = 0;
+ goto out;
+ }
+
+ host->fixed = pinctrl_lookup_state(host->pinctrl,
+ PINCTRL_STATE_DEFAULT);
+ if (IS_ERR(host->fixed)) {
+ dev_dbg(host->dev,
+ "pins are not configured from the driver\n");
+ host->fixed = NULL;
+ ret = 0;
+ goto out;
+ }
+
+ ret = pinctrl_select_state(host->pinctrl, host->fixed);
+ if (ret < 0)
+ goto err;
+
+ /* For most cases we don't have wake-ups, and exit after this */
+ host->active = pinctrl_lookup_state(host->pinctrl, "active");
+ if (IS_ERR(host->active)) {
+ ret = PTR_ERR(host->active);
+ host->active = NULL;
+ return 0;
+ }
+
+ host->idle = pinctrl_lookup_state(host->pinctrl,
+ PINCTRL_STATE_IDLE);
+ if (IS_ERR(host->idle)) {
+ ret = PTR_ERR(host->idle);
+ host->idle = NULL;
+ goto err;
+ }
+
+ /* Let's make sure the active and idle states work */
+ ret = pinctrl_select_state(host->pinctrl, host->idle);
+ if (ret < 0)
+ goto err;
+
+ ret = pinctrl_select_state(host->pinctrl, host->active);
+ if (ret < 0)
+ goto err;
+
+ dev_info(mmc_dev(host->mmc), "pins configured for wake-up events\n");
+
+ return 0;
+
+err:
+ dev_err(mmc_dev(host->mmc), "pins configuration error: %i\n", ret);
+
+out:
+ return ret;
+}
+
/*
* Start clock to the card
*/
@@ -1858,7 +1943,6 @@ 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) {
@@ -2083,10 +2167,26 @@ 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");
+ ret = omap_hsmmc_pin_init(host);
+ if (ret)
+ goto err_pinctrl_state;
+
+ if (pdata->controller_flags & OMAP_HSMMC_SWAKEUP_MISSING) {
+ ret = irq_of_parse_and_map(pdev->dev.of_node, 1);
+ if (ret) {
+ host->gpio_sdio_irq = ret;
+
+ /* prevent auto-enabling of IRQ */
+ irq_set_status_flags(host->gpio_sdio_irq, IRQ_NOAUTOEN);
+ ret = request_irq(host->gpio_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;
+ }
+ }
/*
* For now, only support SDIO interrupt if we are booted with
@@ -2098,8 +2198,14 @@ static int omap_hsmmc_probe(struct platform_device *pdev)
if (pdev->dev.of_node) {
mmc->caps |= MMC_CAP_SDIO_IRQ;
if (pdata->controller_flags & OMAP_HSMMC_SWAKEUP_MISSING) {
- /* no wakeup from deeper power states, use polling */
- mmc->caps &= ~MMC_CAP_SDIO_IRQ;
+ /* use GPIO to wakeup from deeper power states */
+ if (!host->idle || !host->gpio_sdio_irq) {
+ dev_warn(mmc_dev(host->mmc),
+ "Disable SDIO IRQ workaround, GPIO IRQ or pinctrl idle state missing, falling back to polling\n");
+ mmc->caps &= ~MMC_CAP_SDIO_IRQ;
+ } else {
+ host->flags |= HSMMC_SWAKEUP_QUIRK;
+ }
}
}
@@ -2127,7 +2233,13 @@ static int omap_hsmmc_probe(struct platform_device *pdev)
err_slot_name:
mmc_remove_host(mmc);
- free_irq(mmc_slot(host).card_detect_irq, host);
+ if (host->gpio_sdio_irq)
+ free_irq(host->gpio_sdio_irq, host);
+err_irq_sdio:
+ devm_pinctrl_put(host->pinctrl);
+err_pinctrl_state:
+ if ((mmc_slot(host).card_detect_irq))
+ free_irq(mmc_slot(host).card_detect_irq, host);
err_irq_cd:
if (host->use_reg)
omap_hsmmc_reg_put(host);
@@ -2172,13 +2284,15 @@ static int omap_hsmmc_remove(struct platform_device *pdev)
if (host->pdata->cleanup)
host->pdata->cleanup(&pdev->dev);
free_irq(host->irq, host);
+ if ((host->gpio_sdio_irq))
+ free_irq(host->gpio_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);
@@ -2234,6 +2348,9 @@ static int omap_hsmmc_suspend(struct device *dev)
OMAP_HSMMC_READ(host->base, HCTL) & ~SDBP);
}
+ if (host->flags & HSMMC_SWAKEUP_QUIRK)
+ disable_irq(host->gpio_sdio_irq);
+
if (host->dbclk)
clk_disable_unprepare(host->dbclk);
@@ -2259,6 +2376,9 @@ static int omap_hsmmc_resume(struct device *dev)
omap_hsmmc_protect_card(host);
+ if (host->flags & HSMMC_SWAKEUP_QUIRK)
+ enable_irq(host->gpio_sdio_irq);
+
pm_runtime_mark_last_busy(host->dev);
pm_runtime_put_autosuspend(host->dev);
return 0;
@@ -2274,23 +2394,61 @@ 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 (host->flags & HSMMC_SWAKEUP_QUIRK) {
+ OMAP_HSMMC_WRITE(host->base, ISE, 0);
+ OMAP_HSMMC_WRITE(host->base, IE, 0);
+ OMAP_HSMMC_WRITE(host->base, STAT, STAT_CLEAR);
+
+ ret = pinctrl_select_state(host->pinctrl, host->idle);
+ if (ret < 0)
+ dev_warn(mmc_dev(host->mmc), "Unable to select idle pinmux\n");
+
+ spin_lock_irqsave(&host->irq_lock, flags);
+ if (host->flags & HSMMC_SDIO_IRQ_ENABLED) {
+ enable_irq(host->gpio_sdio_irq);
+ host->flags |= HSMMC_CIRQ_GPIO_ENABLED;
+ }
+ spin_unlock_irqrestore(&host->irq_lock, flags);
+ }
+
+ 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 (host->flags & HSMMC_SWAKEUP_QUIRK) {
+
+ spin_lock_irqsave(&host->irq_lock, flags);
+ if (host->flags & HSMMC_CIRQ_GPIO_ENABLED) {
+ disable_irq_nosync(host->gpio_sdio_irq);
+ host->flags &= ~HSMMC_CIRQ_GPIO_ENABLED;
+ }
+ spin_unlock_irqrestore(&host->irq_lock, flags);
+
+ ret = pinctrl_select_state(host->pinctrl, host->active);
+ if (ret < 0)
+ dev_warn(mmc_dev(host->mmc), "Unable to select active pinmux\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);
+ }
+ return ret;
}
static struct dev_pm_ops omap_hsmmc_dev_pm_ops = {
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 as well as the implementation of omap_hsmmc_pin_init. Signed-off-by: Andreas Fenkart <afenkart@gmail.com> --- .../devicetree/bindings/mmc/ti-omap-hsmmc.txt | 50 ++++++ drivers/mmc/host/omap_hsmmc.c | 180 ++++++++++++++++++-- 2 files changed, 219 insertions(+), 11 deletions(-)