Merge "NFC: Inform CLF whenever eSE is powered off"

drivers/nfc/nq-nci.c

@@ -47,6 +47,7 @@ MODULE_DEVICE_TABLE(of, msm_match_table);
 
 #define MAX_BUFFER_SIZE			(320)
 #define WAKEUP_SRC_TIMEOUT		(2000)
+#define MAX_RETRY_COUNT			3
 
 struct nqx_dev {
 	wait_queue_head_t	read_wq;
@@ -264,6 +265,35 @@ out:
 	return ret;
 }
 
+/**
+ * nqx_standby_write()
+ * @buf:       pointer to data buffer
+ * @len:       # of bytes need to transfer
+ *
+ * write data buffer over I2C and retry
+ * if NFCC is in stand by mode
+ *
+ * Return: # of bytes written or -ve value in case of error
+ */
+static int nqx_standby_write(struct nqx_dev *nqx_dev,
+				const unsigned char *buf, size_t len)
+{
+	int ret = -EINVAL;
+	int retry_cnt;
+
+	for (retry_cnt = 1; retry_cnt <= MAX_RETRY_COUNT; retry_cnt++) {
+		ret = i2c_master_send(nqx_dev->client, buf, len);
+		if (ret < 0) {
+			dev_err(&nqx_dev->client->dev,
+				"%s: write failed, Maybe in Standby Mode - Retry(%d)\n",
+				 __func__, retry_cnt);
+			usleep_range(1000, 1100);
+		} else if (ret == len)
+			break;
+	}
+	return ret;
+}
+
 /*
  * Power management of the eSE
  * NFC & eSE ON : NFC_EN high and eSE_pwr_req high.
@@ -273,39 +303,95 @@ out:
 static int nqx_ese_pwr(struct nqx_dev *nqx_dev, unsigned long int arg)
 {
 	int r = -1;
+	const unsigned char svdd_off_cmd_warn[] =  {0x2F, 0x31, 0x01, 0x01};
+	const unsigned char svdd_off_cmd_done[] =  {0x2F, 0x31, 0x01, 0x00};
+
+	if (!gpio_is_valid(nqx_dev->ese_gpio)) {
+		dev_err(&nqx_dev->client->dev,
+			"%s: ese_gpio is not valid\n", __func__);
+		return -EINVAL;
+	}
 
-	/* Let's store the NFC_EN pin state */
 	if (arg == 0) {
 		/*
 		 * We want to power on the eSE and to do so we need the
 		 * eSE_pwr_req pin and the NFC_EN pin to be high
 		 */
-		nqx_dev->nfc_ven_enabled = gpio_get_value(nqx_dev->en_gpio);
-		if (!nqx_dev->nfc_ven_enabled) {
-			gpio_set_value(nqx_dev->en_gpio, 1);
-			/* hardware dependent delay */
-			usleep_range(1000, 1100);
-		}
-		if (gpio_is_valid(nqx_dev->ese_gpio)) {
+		if (gpio_get_value(nqx_dev->ese_gpio)) {
+			dev_dbg(&nqx_dev->client->dev, "ese_gpio is already high\n");
+			r = 0;
+		} else {
+			/**
+			 * Let's store the NFC_EN pin state
+			 * only if the eSE is not yet on
+			 */
+			nqx_dev->nfc_ven_enabled =
+					gpio_get_value(nqx_dev->en_gpio);
+			if (!nqx_dev->nfc_ven_enabled) {
+				gpio_set_value(nqx_dev->en_gpio, 1);
+				/* hardware dependent delay */
+				usleep_range(1000, 1100);
+			}
+			gpio_set_value(nqx_dev->ese_gpio, 1);
 			if (gpio_get_value(nqx_dev->ese_gpio)) {
-				dev_dbg(&nqx_dev->client->dev, "ese_gpio is already high\n");
+				dev_dbg(&nqx_dev->client->dev, "ese_gpio is enabled\n");
 				r = 0;
-			} else {
-				gpio_set_value(nqx_dev->ese_gpio, 1);
-				if (gpio_get_value(nqx_dev->ese_gpio)) {
-					dev_dbg(&nqx_dev->client->dev, "ese_gpio is enabled\n");
-					r = 0;
-				}
 			}
 		}
 	} else if (arg == 1) {
-		if (gpio_is_valid(nqx_dev->ese_gpio)) {
-			gpio_set_value(nqx_dev->ese_gpio, 0);
-			if (!gpio_get_value(nqx_dev->ese_gpio)) {
-				dev_dbg(&nqx_dev->client->dev, "ese_gpio is disabled\n");
-				r = 0;
+		if (nqx_dev->nfc_ven_enabled &&
+			((nqx_dev->nqx_info.info.chip_type == NFCC_NQ_220) ||
+			(nqx_dev->nqx_info.info.chip_type == NFCC_PN66T))) {
+			/**
+			 * Let's inform the CLF we're
+			 * powering off the eSE
+			 */
+			r = nqx_standby_write(nqx_dev, svdd_off_cmd_warn,
+						sizeof(svdd_off_cmd_warn));
+			if (r < 0) {
+				dev_err(&nqx_dev->client->dev,
+					"%s: write failed after max retry\n",
+					 __func__);
+				return -ENXIO;
 			}
+			dev_dbg(&nqx_dev->client->dev,
+				"%s: svdd_off_cmd_warn sent\n", __func__);
+
+			/* let's power down the eSE */
+			gpio_set_value(nqx_dev->ese_gpio, 0);
+			dev_dbg(&nqx_dev->client->dev,
+				"%s: nqx_dev->ese_gpio set to 0\n", __func__);
+
+			/**
+			 * Time needed for the SVDD capacitor
+			 * to get discharged
+			 */
+			usleep_range(8000, 8100);
+
+			/* Let's inform the CLF the eSE is now off */
+			r = nqx_standby_write(nqx_dev, svdd_off_cmd_done,
+						sizeof(svdd_off_cmd_done));
+			if (r < 0) {
+				dev_err(&nqx_dev->client->dev,
+					"%s: write failed after max retry\n",
+					 __func__);
+				return -ENXIO;
+			}
+			dev_dbg(&nqx_dev->client->dev,
+				"%s: svdd_off_cmd_done sent\n", __func__);
+		} else {
+			/**
+			 * In case the NFC is off,
+			 * there's no need to send the i2c commands
+			 */
+			gpio_set_value(nqx_dev->ese_gpio, 0);
 		}
+
+		if (!gpio_get_value(nqx_dev->ese_gpio)) {
+			dev_dbg(&nqx_dev->client->dev, "ese_gpio is disabled\n");
+			r = 0;
+		}
+
 		if (!nqx_dev->nfc_ven_enabled) {
 			/* hardware dependent delay */
 			usleep_range(1000, 1100);
@@ -313,12 +399,7 @@ static int nqx_ese_pwr(struct nqx_dev *nqx_dev, unsigned long int arg)
 			gpio_set_value(nqx_dev->en_gpio, 0);
 		}
 	} else if (arg == 3) {
-		if (!nqx_dev->nfc_ven_enabled)
-			r = 0;
-		else {
-			if (gpio_is_valid(nqx_dev->ese_gpio))
-				r = gpio_get_value(nqx_dev->ese_gpio);
-		}
+		r = gpio_get_value(nqx_dev->ese_gpio);
 	}
 	return r;
 }
@@ -624,6 +705,10 @@ static int nfcc_hw_check(struct i2c_client *client, struct nqx_dev *nqx_dev)
 		dev_dbg(&client->dev,
 		"%s: ## NFCC == NQ330 ##\n", __func__);
 		break;
+	case NFCC_PN66T:
+		dev_dbg(&client->dev,
+		"%s: ## NFCC == PN66T ##\n", __func__);
+		break;
 	default:
 		dev_err(&client->dev,
 		"%s: - NFCC HW not Supported\n", __func__);

drivers/nfc/nq-nci.h

@@ -48,7 +48,7 @@ enum nfcc_chip_variant {
 	NFCC_NQ_220			= 0x58,	/**< NFCC NQ220 */
 	NFCC_NQ_310			= 0x40,	/**< NFCC NQ310 */
 	NFCC_NQ_330			= 0x51,	/**< NFCC NQ330 */
+	NFCC_PN66T			= 0x18,	/**< NFCC PN66T */
 	NFCC_NOT_SUPPORTED	        = 0xFF	/**< NFCC is not supported */
 };
-
 #endif