NFC: trf7970a: Don't assume CONFIG_PM_RUNTIME is enabled

The current code assumes that CONFIG_PM_RUNTIME
is always defined so it won't power up the trf7970a
when it isn't enabled.  Fix this by moving the power
up/down code from the pm_runtime_resume/suspend
routines into their own routines and calling the
power up function from the probe routine.  This
ensures the device is powered up even when
CONFIG_PM_RUNTIME is not defined.

In order to not power on/off a device that is
already powered on/off, create a new state to
indicate that the power is off (TRF7970A_ST_PWR_OFF).

Signed-off-by: Mark A. Greer <mgreer@animalcreek.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>

1 files changed, 96 insertions, 36 deletions

diff --git a/drivers/nfc/trf7970a.c b/drivers/nfc/trf7970a.c
index cda854b98cf3..84a9c3f78621 100644
--- a/drivers/nfc/trf7970a.c
+++ b/drivers/nfc/trf7970a.c
@@ -332,6 +332,7 @@
                 (ISO15693_REQ_FLAG_SUB_CARRIER | ISO15693_REQ_FLAG_DATA_RATE)
 
 enum trf7970a_state {
+        TRF7970A_ST_PWR_OFF,
         TRF7970A_ST_RF_OFF,
         TRF7970A_ST_IDLE,
         TRF7970A_ST_IDLE_RX_BLOCKED,
@@ -877,6 +878,12 @@ static int trf7970a_switch_rf_on(struct trf7970a *trf)
 
         pm_runtime_get_sync(trf->dev);
 
+        if (trf->state != TRF7970A_ST_RF_OFF) { /* Power on, RF off */
+                dev_err(trf->dev, "%s - Incorrect state: %d\n", __func__,
+                                trf->state);
+                return -EINVAL;
+        }
+
         ret = trf7970a_init(trf);
         if (ret) {
                 dev_err(trf->dev, "%s - Can't initialize: %d\n", __func__, ret);
@@ -899,6 +906,7 @@ static int trf7970a_switch_rf(struct nfc_digital_dev *ddev, bool on)
 
         if (on) {
                 switch (trf->state) {
+                case TRF7970A_ST_PWR_OFF:
                 case TRF7970A_ST_RF_OFF:
                         ret = trf7970a_switch_rf_on(trf);
                         break;
@@ -913,6 +921,7 @@ static int trf7970a_switch_rf(struct nfc_digital_dev *ddev, bool on)
                 }
         } else {
                 switch (trf->state) {
+                case TRF7970A_ST_PWR_OFF:
                 case TRF7970A_ST_RF_OFF:
                         break;
                 default:
@@ -1045,7 +1054,8 @@ static int trf7970a_in_configure_hw(struct nfc_digital_dev *ddev, int type,
 
         mutex_lock(&trf->lock);
 
-        if (trf->state == TRF7970A_ST_RF_OFF) {
+        if ((trf->state == TRF7970A_ST_PWR_OFF) ||
+                        (trf->state == TRF7970A_ST_RF_OFF)) {
                 ret = trf7970a_switch_rf_on(trf);
                 if (ret)
                         goto err_unlock;
@@ -1316,6 +1326,65 @@ static struct nfc_digital_ops trf7970a_nfc_ops = {
         .abort_cmd              = trf7970a_abort_cmd,
 };
 
+static int trf7970a_power_up(struct trf7970a *trf)
+{
+        int ret;
+
+        dev_dbg(trf->dev, "Powering up - state: %d\n", trf->state);
+
+        if (trf->state != TRF7970A_ST_PWR_OFF)
+                return 0;
+
+        ret = regulator_enable(trf->regulator);
+        if (ret) {
+                dev_err(trf->dev, "%s - Can't enable VIN: %d\n", __func__, ret);
+                return ret;
+        }
+
+        usleep_range(5000, 6000);
+
+        if (!(trf->quirks & TRF7970A_QUIRK_EN2_MUST_STAY_LOW)) {
+                gpio_set_value(trf->en2_gpio, 1);
+                usleep_range(1000, 2000);
+        }
+
+        gpio_set_value(trf->en_gpio, 1);
+
+        usleep_range(20000, 21000);
+
+        trf->state = TRF7970A_ST_RF_OFF;
+
+        return 0;
+}
+
+static int trf7970a_power_down(struct trf7970a *trf)
+{
+        int ret;
+
+        dev_dbg(trf->dev, "Powering down - state: %d\n", trf->state);
+
+        if (trf->state == TRF7970A_ST_PWR_OFF)
+                return 0;
+
+        if (trf->state != TRF7970A_ST_RF_OFF) {
+                dev_dbg(trf->dev, "Can't power down - not RF_OFF state (%d)\n",
+                                trf->state);
+                return -EBUSY;
+        }
+
+        gpio_set_value(trf->en_gpio, 0);
+        gpio_set_value(trf->en2_gpio, 0);
+
+        ret = regulator_disable(trf->regulator);
+        if (ret)
+                dev_err(trf->dev, "%s - Can't disable VIN: %d\n", __func__,
+                                ret);
+
+        trf->state = TRF7970A_ST_PWR_OFF;
+
+        return ret;
+}
+
 static int trf7970a_get_autosuspend_delay(struct device_node *np)
 {
         int autosuspend_delay, ret;
@@ -1348,7 +1417,7 @@ static int trf7970a_probe(struct spi_device *spi)
         if (!trf)
                 return -ENOMEM;
 
-        trf->state = TRF7970A_ST_RF_OFF;
+        trf->state = TRF7970A_ST_PWR_OFF;
         trf->dev = &spi->dev;
         trf->spi = spi;
 
@@ -1442,19 +1511,29 @@ static int trf7970a_probe(struct spi_device *spi)
 
         pm_runtime_set_autosuspend_delay(trf->dev, autosuspend_delay);
         pm_runtime_use_autosuspend(trf->dev);
+
+        ret = trf7970a_power_up(trf);
+        if (ret)
+                goto err_free_ddev;
+
+        pm_runtime_set_active(trf->dev);
         pm_runtime_enable(trf->dev);
+        pm_runtime_mark_last_busy(trf->dev);
 
         ret = nfc_digital_register_device(trf->ddev);
         if (ret) {
                 dev_err(trf->dev, "Can't register NFC digital device: %d\n",
                                 ret);
-                goto err_free_ddev;
+                goto err_power_down;
         }
 
         return 0;
 
-err_free_ddev:
+err_power_down:
         pm_runtime_disable(trf->dev);
+        pm_runtime_set_suspended(trf->dev);
+        trf7970a_power_down(trf);
+err_free_ddev:
         nfc_digital_free_device(trf->ddev);
 err_disable_regulator:
         regulator_disable(trf->regulator);
@@ -1478,15 +1557,18 @@ static int trf7970a_remove(struct spi_device *spi)
                 /* FALLTHROUGH */
         case TRF7970A_ST_IDLE:
         case TRF7970A_ST_IDLE_RX_BLOCKED:
-                pm_runtime_put_sync(trf->dev);
+                trf7970a_switch_rf_off(trf);
                 break;
         default:
                 break;
         }
 
-        mutex_unlock(&trf->lock);
-
         pm_runtime_disable(trf->dev);
+        pm_runtime_set_suspended(trf->dev);
+
+        trf7970a_power_down(trf);
+
+        mutex_unlock(&trf->lock);
 
         nfc_digital_unregister_device(trf->ddev);
         nfc_digital_free_device(trf->ddev);
@@ -1507,18 +1589,11 @@ static int trf7970a_pm_runtime_suspend(struct device *dev)
 
         dev_dbg(dev, "Runtime suspend\n");
 
-        if (trf->state != TRF7970A_ST_RF_OFF) {
-                dev_dbg(dev, "Can't suspend - not in OFF state (%d)\n",
-                                trf->state);
-                return -EBUSY;
-        }
+        mutex_lock(&trf->lock);
 
-        gpio_set_value(trf->en_gpio, 0);
-        gpio_set_value(trf->en2_gpio, 0);
+        ret = trf7970a_power_down(trf);
 
-        ret = regulator_disable(trf->regulator);
-        if (ret)
-                dev_err(dev, "%s - Can't disable VIN: %d\n", __func__, ret);
+        mutex_unlock(&trf->lock);
 
         return ret;
 }
@@ -1531,26 +1606,11 @@ static int trf7970a_pm_runtime_resume(struct device *dev)
 
         dev_dbg(dev, "Runtime resume\n");
 
-        ret = regulator_enable(trf->regulator);
-        if (ret) {
-                dev_err(dev, "%s - Can't enable VIN: %d\n", __func__, ret);
-                return ret;
-        }
-
-        usleep_range(5000, 6000);
-
-        if (!(trf->quirks & TRF7970A_QUIRK_EN2_MUST_STAY_LOW)) {
-                gpio_set_value(trf->en2_gpio, 1);
-                usleep_range(1000, 2000);
-        }
-
-        gpio_set_value(trf->en_gpio, 1);
-
-        usleep_range(20000, 21000);
+        ret = trf7970a_power_up(trf);
+        if (!ret)
+                pm_runtime_mark_last_busy(dev);
 
-        pm_runtime_mark_last_busy(dev);
-
-        return 0;
+        return ret;
 }
 #endif