[PATCH v2 6/6] can: m_can: Add support for transceiver as phy

[Aswath Govindraju <a-govindraju@xxxxxx>]

From: Faiz Abbas <faiz_abbas@xxxxxx>

Add support for implementing transceiver node as phy. The max_bitrate is
obtained by getting a phy attribute.

Signed-off-by: Faiz Abbas <faiz_abbas@xxxxxx>
Signed-off-by: Aswath Govindraju <a-govindraju@xxxxxx>
---
 drivers/net/can/m_can/m_can.c          | 18 ++++++++++++++++++
 drivers/net/can/m_can/m_can.h          |  2 ++
 drivers/net/can/m_can/m_can_platform.c | 15 +++++++++++++++
 3 files changed, 35 insertions(+)

diff --git a/drivers/net/can/m_can/m_can.c b/drivers/net/can/m_can/m_can.c
index 34073cd077e4..4807a1f69cc7 100644
--- a/drivers/net/can/m_can/m_can.c
+++ b/drivers/net/can/m_can/m_can.c
@@ -21,6 +21,7 @@
 #include <linux/iopoll.h>
 #include <linux/can/dev.h>
 #include <linux/pinctrl/consumer.h>
+#include <linux/phy/phy.h>
 
 #include "m_can.h"
 
@@ -1514,6 +1515,7 @@ static void m_can_stop(struct net_device *dev)
 static int m_can_close(struct net_device *dev)
 {
 	struct m_can_classdev *cdev = netdev_priv(dev);
+	int err;
 
 	netif_stop_queue(dev);
 
@@ -1536,6 +1538,14 @@ static int m_can_close(struct net_device *dev)
 	close_candev(dev);
 	can_led_event(dev, CAN_LED_EVENT_STOP);
 
+	if (cdev->transceiver) {
+		err = phy_power_off(cdev->transceiver);
+		if (err) {
+			netdev_err(dev, "error powering off phy, err=%d\n", err);
+			return err;
+		}
+	}
+
 	return 0;
 }
 
@@ -1720,6 +1730,14 @@ static int m_can_open(struct net_device *dev)
 	struct m_can_classdev *cdev = netdev_priv(dev);
 	int err;
 
+	if (cdev->transceiver) {
+		err = phy_power_on(cdev->transceiver);
+		if (err) {
+			netdev_err(dev, "error powering on phy, err=%d\n", err);
+			return err;
+		}
+	}
+
 	err = m_can_clk_start(cdev);
 	if (err)
 		return err;
diff --git a/drivers/net/can/m_can/m_can.h b/drivers/net/can/m_can/m_can.h
index ace071c3e58c..38cad068abad 100644
--- a/drivers/net/can/m_can/m_can.h
+++ b/drivers/net/can/m_can/m_can.h
@@ -28,6 +28,7 @@
 #include <linux/iopoll.h>
 #include <linux/can/dev.h>
 #include <linux/pinctrl/consumer.h>
+#include <linux/phy/phy.h>
 
 /* m_can lec values */
 enum m_can_lec_type {
@@ -82,6 +83,7 @@ struct m_can_classdev {
 	struct workqueue_struct *tx_wq;
 	struct work_struct tx_work;
 	struct sk_buff *tx_skb;
+	struct phy *transceiver;
 
 	struct can_bittiming_const *bit_timing;
 	struct can_bittiming_const *data_timing;
diff --git a/drivers/net/can/m_can/m_can_platform.c b/drivers/net/can/m_can/m_can_platform.c
index 599de0e08cd7..566ba25fb186 100644
--- a/drivers/net/can/m_can/m_can_platform.c
+++ b/drivers/net/can/m_can/m_can_platform.c
@@ -6,6 +6,7 @@
 // Copyright (C) 2018-19 Texas Instruments Incorporated - http://www.ti.com/
 
 #include <linux/platform_device.h>
+#include <linux/phy/phy.h>
 
 #include "m_can.h"
 
@@ -67,6 +68,7 @@ static int m_can_plat_probe(struct platform_device *pdev)
 	struct resource *res;
 	void __iomem *addr;
 	void __iomem *mram_addr;
+	struct phy *transceiver;
 	int irq, ret = 0;
 
 	mcan_class = m_can_class_allocate_dev(&pdev->dev,
@@ -101,6 +103,18 @@ static int m_can_plat_probe(struct platform_device *pdev)
 		goto probe_fail;
 	}
 
+	transceiver = devm_of_phy_optional_get_by_index(&pdev->dev, pdev->dev.of_node, 0);
+	if (IS_ERR(transceiver)) {
+		ret = PTR_ERR(transceiver);
+		dev_err(&pdev->dev, "error while getting phy, err=%d\n", ret);
+		return ret;
+	}
+
+	if (!transceiver)
+		dev_info(&pdev->dev, "No transceiver phy found\n");
+	else
+		priv->cdev.can.bitrate_max = transceiver->attrs.max_link_rate;
+
 	priv->base = addr;
 	priv->mram_base = mram_addr;
 
@@ -108,6 +122,7 @@ static int m_can_plat_probe(struct platform_device *pdev)
 	mcan_class->pm_clock_support = 1;
 	mcan_class->can.clock.freq = clk_get_rate(mcan_class->cclk);
 	mcan_class->dev = &pdev->dev;
+	mcan_class->transceiver = transceiver;
 
 	mcan_class->ops = &m_can_plat_ops;
 
-- 
2.17.1