greybus: arche-platform: Do not assert wake/detect signal to SVC

With new definition of AP module boot flow (from HotPlug camp),
AP is not supposed to send any wake/detect signal to SVC, instead,
during boot SVC would straight away send wake_out pulse on wake/detect
line.
Note that, pin configuration of wake/detect line would be set to
active-high by default, so wake/detect line would always stay high,
unless SVC drives it. AP module uses wake/detect line strictly in input
mode.

Testing Done: Tested on EVT1.5 platform.

Note: We are yet to decide on PM support for APBx, so we may need to
generate/handshake with SVC over wake/detect line in the future. As of
now, follow the implementation and add stuff as and when they come.

Signed-off-by: Vaibhav Hiremath <vaibhav.hiremath@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

diff --git a/drivers/staging/greybus/arche-platform.c b/drivers/staging/greybus/arche-platform.c
index e3854349b36c0833aeb2ca276f3ad3a0e7c83763..c02ff58ddefee4b4b98b8d0f76c35545d7b3c444 100644 (file)
--- a/drivers/staging/greybus/arche-platform.c
+++ b/drivers/staging/greybus/arche-platform.c
@@ -207,9 +207,6 @@ static int apb_poweroff(struct device *dev, void *data)
 
 static void assert_wakedetect(struct arche_platform_drvdata *arche_pdata)
 {
-       /* Assert wake/detect = Detect event from AP */
-       gpio_direction_output(arche_pdata->wake_detect_gpio, 1);
-
        /* Enable interrupt here, to read event back from SVC */
        gpio_direction_input(arche_pdata->wake_detect_gpio);
        enable_irq(arche_pdata->wake_detect_irq);
@@ -371,9 +368,7 @@ static void arche_platform_poweroff_seq(struct arche_platform_drvdata *arche_pda
        /* If in fw_flashing mode, then no need to repeate things again */
        if (arche_pdata->state != ARCHE_PLATFORM_STATE_FW_FLASHING) {
                disable_irq(arche_pdata->wake_detect_irq);
-               /* Send disconnect/detach event to SVC */
-               gpio_direction_output(arche_pdata->wake_detect_gpio, 0);
-               usleep_range(100, 200);
+
                spin_lock_irqsave(&arche_pdata->wake_lock, flags);
                arche_platform_set_wake_detect_state(arche_pdata,
                                                     WD_STATE_IDLE);
@@ -411,9 +406,9 @@ static ssize_t state_store(struct device *dev,
                if (arche_pdata->state == ARCHE_PLATFORM_STATE_ACTIVE)
                        goto exit;
 
+               assert_wakedetect(arche_pdata);
                ret = arche_platform_coldboot_seq(arche_pdata);
 
-               assert_wakedetect(arche_pdata);
        } else if (sysfs_streq(buf, "standby")) {
                if (arche_pdata->state == ARCHE_PLATFORM_STATE_STANDBY)
                        goto exit;
@@ -484,8 +479,8 @@ static int arche_platform_pm_notifier(struct notifier_block *notifier,
                arche_platform_poweroff_seq(arche_pdata);
                break;
        case PM_POST_SUSPEND:
-               arche_platform_coldboot_seq(arche_pdata);
                assert_wakedetect(arche_pdata);
+               arche_platform_coldboot_seq(arche_pdata);
                break;
        default:
                break;
@@ -588,8 +583,7 @@ static int arche_platform_probe(struct platform_device *pdev)
                                arche_pdata->wake_detect_gpio);
                return ret;
        }
-       /* deassert wake detect */
-       gpio_direction_output(arche_pdata->wake_detect_gpio, 0);
+
        arche_platform_set_wake_detect_state(arche_pdata, WD_STATE_IDLE);
 
        arche_pdata->dev = &pdev->dev;
@@ -608,8 +602,8 @@ static int arche_platform_probe(struct platform_device *pdev)
                dev_err(dev, "failed to request wake detect IRQ %d\n", ret);
                return ret;
        }
-       /* Enable it only after  sending wake/detect event */
-       disable_irq(arche_pdata->wake_detect_irq);
+
+       assert_wakedetect(arche_pdata);
 
        ret = device_create_file(dev, &dev_attr_state);
        if (ret) {
@@ -630,8 +624,6 @@ static int arche_platform_probe(struct platform_device *pdev)
                goto err_populate;
        }
 
-       assert_wakedetect(arche_pdata);
-
        arche_pdata->pm_notifier.notifier_call = arche_platform_pm_notifier;
        ret = register_pm_notifier(&arche_pdata->pm_notifier);
        mutex_unlock(&arche_pdata->platform_state_mutex);