can: at91_can: add CAN transceiver support

Add support for Linux-PHY based CAN transceivers.

Link: https://lore.kernel.org/all/20231005-at91_can-rx_offload-v2-16-9987d53600e0@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

diff --git a/drivers/net/can/at91_can.c b/drivers/net/can/at91_can.c
index bfe414581fa1018432317839bffdacde3478a5ec..94e9740c80de22832c266b2e1c95db68e07c8ab8 100644 (file)
--- a/drivers/net/can/at91_can.c
+++ b/drivers/net/can/at91_can.c
@@ -16,6 +16,7 @@
 #include <linux/module.h>
 #include <linux/netdevice.h>
 #include <linux/of.h>
+#include <linux/phy/phy.h>
 #include <linux/platform_device.h>
 #include <linux/rtnetlink.h>
 #include <linux/skbuff.h>
@@ -150,6 +151,7 @@ struct at91_devtype_data {
 struct at91_priv {
        struct can_priv can;            /* must be the first member! */
        struct napi_struct napi;
+       struct phy *transceiver;
 
        void __iomem *reg_base;
 
@@ -1118,20 +1120,24 @@ static int at91_open(struct net_device *dev)
        struct at91_priv *priv = netdev_priv(dev);
        int err;
 
-       err = clk_prepare_enable(priv->clk);
+       err = phy_power_on(priv->transceiver);
        if (err)
                return err;
 
        /* check or determine and set bittime */
        err = open_candev(dev);
        if (err)
-               goto out;
+               goto out_phy_power_off;
+
+       err = clk_prepare_enable(priv->clk);
+       if (err)
+               goto out_close_candev;
 
        /* register interrupt handler */
        err = request_irq(dev->irq, at91_irq, IRQF_SHARED,
                          dev->name, dev);
        if (err)
-               goto out_close;
+               goto out_clock_disable_unprepare;
 
        /* start chip and queuing */
        at91_chip_start(dev);
@@ -1140,10 +1146,12 @@ static int at91_open(struct net_device *dev)
 
        return 0;
 
- out_close:
-       close_candev(dev);
- out:
+ out_clock_disable_unprepare:
        clk_disable_unprepare(priv->clk);
+ out_close_candev:
+       close_candev(dev);
+ out_phy_power_off:
+       phy_power_off(priv->transceiver);
 
        return err;
 }
@@ -1160,6 +1168,7 @@ static int at91_close(struct net_device *dev)
 
        free_irq(dev->irq, dev);
        clk_disable_unprepare(priv->clk);
+       phy_power_off(priv->transceiver);
 
        close_candev(dev);
 
@@ -1284,6 +1293,7 @@ static const struct at91_devtype_data *at91_can_get_driver_data(struct platform_
 static int at91_can_probe(struct platform_device *pdev)
 {
        const struct at91_devtype_data *devtype_data;
+       struct phy *transceiver;
        struct net_device *dev;
        struct at91_priv *priv;
        struct resource *res;
@@ -1332,6 +1342,13 @@ static int at91_can_probe(struct platform_device *pdev)
                goto exit_iounmap;
        }
 
+       transceiver = devm_phy_optional_get(&pdev->dev, NULL);
+       if (IS_ERR(transceiver)) {
+               err = PTR_ERR(transceiver);
+               dev_err_probe(&pdev->dev, err, "failed to get phy\n");
+               goto exit_iounmap;
+       }
+
        dev->netdev_ops = &at91_netdev_ops;
        dev->ethtool_ops = &at91_ethtool_ops;
        dev->irq = irq;
@@ -1352,6 +1369,9 @@ static int at91_can_probe(struct platform_device *pdev)
 
        netif_napi_add_weight(dev, &priv->napi, at91_poll, get_mb_rx_num(priv));
 
+       if (transceiver)
+               priv->can.bitrate_max = transceiver->attrs.max_link_rate;
+
        if (at91_is_sam9263(priv))
                dev->sysfs_groups[0] = &at91_sysfs_attr_group;