[RFC PATCH v2 1/4] can xl dummy driver from Vincent

[Oliver Hartkopp <socketcan@hartkopp.net>]

added control mode/supported output

Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
---
 drivers/net/can/Kconfig   |   8 ++
 drivers/net/can/Makefile  |   1 +
 drivers/net/can/dummyxl.c | 226 ++++++++++++++++++++++++++++++++++++++
 3 files changed, 235 insertions(+)
 create mode 100644 drivers/net/can/dummyxl.c

diff --git a/drivers/net/can/Kconfig b/drivers/net/can/Kconfig
index cf989bea9aa3..a8bc5f4e752f 100644
--- a/drivers/net/can/Kconfig
+++ b/drivers/net/can/Kconfig
@@ -122,10 +122,18 @@ config CAN_CAN327
 	  Please refer to the documentation for information on how to use it:
 	  Documentation/networking/device_drivers/can/can327.rst
 
 	  If this driver is built as a module, it will be called can327.
 
+config CAN_DUMMY_XL
+	tristate "Dummy CAN XL"
+	help
+	  A dummy module just to check the CAN XL netlink interface. Do not
+	  merge this.
+
+	  If this driver is built as a module, it will be called dummyxl.
+
 config CAN_FLEXCAN
 	tristate "Support for Freescale FLEXCAN based chips"
 	depends on OF || COLDFIRE || COMPILE_TEST
 	depends on HAS_IOMEM
 	select CAN_RX_OFFLOAD
diff --git a/drivers/net/can/Makefile b/drivers/net/can/Makefile
index a71db2cfe990..ff8e00fa26e3 100644
--- a/drivers/net/can/Makefile
+++ b/drivers/net/can/Makefile
@@ -19,10 +19,11 @@ obj-$(CONFIG_CAN_AT91)		+= at91_can.o
 obj-$(CONFIG_CAN_BXCAN)		+= bxcan.o
 obj-$(CONFIG_CAN_CAN327)	+= can327.o
 obj-$(CONFIG_CAN_CC770)		+= cc770/
 obj-$(CONFIG_CAN_C_CAN)		+= c_can/
 obj-$(CONFIG_CAN_CTUCANFD)	+= ctucanfd/
+obj-$(CONFIG_CAN_DUMMY_XL)	+= dummyxl.o
 obj-$(CONFIG_CAN_FLEXCAN)	+= flexcan/
 obj-$(CONFIG_CAN_GRCAN)		+= grcan.o
 obj-$(CONFIG_CAN_IFI_CANFD)	+= ifi_canfd/
 obj-$(CONFIG_CAN_JANZ_ICAN3)	+= janz-ican3.o
 obj-$(CONFIG_CAN_KVASER_PCIEFD)	+= kvaser_pciefd.o
diff --git a/drivers/net/can/dummyxl.c b/drivers/net/can/dummyxl.c
new file mode 100644
index 000000000000..ac1b579b4c1f
--- /dev/null
+++ b/drivers/net/can/dummyxl.c
@@ -0,0 +1,226 @@
+// SPDX-License-Identifier: GPL-2.0
+
+/* Copyright (c) 2024 Vincent Mailhol <mailhol.vincent@wanadoo.fr> */
+
+#include <linux/errno.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/netdevice.h>
+#include <linux/units.h>
+#include <linux/can.h>
+#include <linux/can/dev.h>
+#include <linux/can/skb.h>
+
+struct dummyxl {
+	struct can_priv can;
+	struct net_device *dev;
+};
+
+static struct dummyxl *dummyxl;
+
+static const struct can_bittiming_const dummyxl_bittiming_const = {
+	.name = "dummyxl nominal",
+	.tseg1_min = 2,
+	.tseg1_max = 256,
+	.tseg2_min = 2,
+	.tseg2_max = 128,
+	.sjw_max = 128,
+	.brp_min = 1,
+	.brp_max = 512,
+	.brp_inc = 1
+};
+
+static const struct can_bittiming_const dummyxl_fd_databittiming_const = {
+	.name = "dummyxl FD",
+	.tseg1_min = 2,
+	.tseg1_max = 256,
+	.tseg2_min = 2,
+	.tseg2_max = 128,
+	.sjw_max = 128,
+	.brp_min = 1,
+	.brp_max = 512,
+	.brp_inc = 1
+};
+
+static const struct can_tdc_const dummyxl_fd_tdc_const = {
+	.tdcv_min = 0,
+	.tdcv_max = 0, /* Manual mode not supported. */
+	.tdco_min = 0,
+	.tdco_max = 127,
+	.tdcf_min = 0,
+	.tdcf_max = 127
+};
+
+static const struct can_bittiming_const dummyxl_xl_databittiming_const = {
+	.name = "dummyxl XL",
+	.tseg1_min = 2,
+	.tseg1_max = 256,
+	.tseg2_min = 2,
+	.tseg2_max = 128,
+	.sjw_max = 128,
+	.brp_min = 1,
+	.brp_max = 512,
+	.brp_inc = 1
+};
+
+static const struct can_tdc_const dummyxl_xl_tdc_const = {
+	.tdcv_min = 0,
+	.tdcv_max = 0, /* Manual mode not supported. */
+	.tdco_min = 0,
+	.tdco_max = 127,
+	.tdcf_min = 0,
+	.tdcf_max = 127
+};
+
+static void dummyxl_print_bittiming(struct net_device *dev, struct can_bittiming *bt)
+{
+	netdev_info(dev, "\tbitrate: %u\n", bt->bitrate);
+	netdev_info(dev, "\tsample_point: %u\n", bt->sample_point);
+	netdev_info(dev, "\ttq: %u\n", bt->tq);
+	netdev_info(dev, "\tprop_seg: %u\n", bt->prop_seg);
+	netdev_info(dev, "\tphase_seg1: %u\n", bt->phase_seg1);
+	netdev_info(dev, "\tphase_seg2: %u\n", bt->phase_seg2);
+	netdev_info(dev, "\tsjw: %u\n", bt->sjw);
+	netdev_info(dev, "\tbrp: %u\n", bt->brp);
+}
+
+static void dummyxl_print_tdc(struct net_device *dev, struct can_tdc *tdc)
+{
+	netdev_info(dev, "\t\ttdcv: %u\n", tdc->tdcv);
+	netdev_info(dev, "\t\ttdco: %u\n", tdc->tdco);
+	netdev_info(dev, "\t\ttdcf: %u\n", tdc->tdcf);
+}
+
+static int dummyxl_netdev_open(struct net_device *dev)
+{
+	struct dummyxl *priv = netdev_priv(dev);
+	struct can_priv *can_priv = &priv->can;
+	int ret;
+
+	netdev_info(dev, "CAN control mode/supported : %08X/%08X\n",
+		    can_priv->ctrlmode, can_priv->ctrlmode_supported);
+	netdev_info(dev, "CAN CC nominal bittiming:\n");
+	dummyxl_print_bittiming(dev, &can_priv->bittiming);
+	netdev_info(dev, "\n");
+
+	if (can_priv->ctrlmode & CAN_CTRLMODE_FD) {
+		netdev_info(dev, "CAN FD databittiming:\n");
+		dummyxl_print_bittiming(dev, &can_priv->fd.data_bittiming);
+		if (can_fd_tdc_is_enabled(can_priv)) {
+			netdev_info(dev, "\tCAN FD TDC:\n");
+			dummyxl_print_tdc(dev, &can_priv->fd.tdc);
+		} else {
+			netdev_info(dev, "\tCAN FD TDC is off\n");
+		}
+	} else {
+		netdev_info(dev, "CAN FD is off\n");
+	}
+	netdev_info(dev, "\n");
+
+	if (can_priv->ctrlmode & CAN_CTRLMODE_XL) {
+		netdev_info(dev, "CAN XL databittiming:\n");
+		dummyxl_print_bittiming(dev, &can_priv->xl.data_bittiming);
+		if (can_xl_tdc_is_enabled(can_priv)) {
+			netdev_info(dev, "\tCAN XL TDC:\n");
+			dummyxl_print_tdc(dev, &can_priv->xl.tdc);
+		} else {
+			netdev_info(dev, "\tCAN XL TDC is off\n");
+		}
+	} else {
+		netdev_info(dev, "CAN XL is off\n");
+	}
+	netdev_info(dev, "\n");
+
+	ret = open_candev(dev);
+	if (ret)
+		return ret;
+	netif_start_queue(dev);
+	netdev_info(dev, "dummyxl is up\n");
+
+	return 0;
+}
+
+static int dummyxl_netdev_close(struct net_device *dev)
+{
+	netif_stop_queue(dev);
+	close_candev(dev);
+	netdev_info(dev, "dummyxl is down\n");
+
+	return 0;
+}
+
+static netdev_tx_t dummyxl_start_xmit(struct sk_buff *skb,
+				      struct net_device *dev)
+{
+	if (can_is_canxl_skb(skb))
+		netdev_info(dev, "Received CAN XL skb\n");
+	else if (can_is_canfd_skb(skb))
+		netdev_info(dev, "Received CAN FD skb\n");
+	else if (can_is_can_skb(skb))
+		netdev_info(dev, "Received Classical CAN skb\n");
+	else
+		netdev_info(dev, "Received an odd skb?!\n");
+	kfree_skb(skb);
+	dev->stats.tx_dropped++;
+
+	return NETDEV_TX_OK;
+}
+
+static const struct net_device_ops dummyxl_netdev_ops = {
+	.ndo_open = dummyxl_netdev_open,
+	.ndo_stop = dummyxl_netdev_close,
+	.ndo_start_xmit = dummyxl_start_xmit,
+};
+
+static int __init dummyxl_init(void)
+{
+	struct net_device *dev;
+	struct dummyxl *priv;
+	int ret;
+
+	dev = alloc_candev(sizeof(struct dummyxl), 0);
+	if (!dev)
+		return -ENOMEM;
+
+	dev->netdev_ops = &dummyxl_netdev_ops;
+	priv = netdev_priv(dev);
+	priv->can.bittiming_const = &dummyxl_bittiming_const;
+	priv->can.bitrate_max = 8 * MEGA /* BPS */;
+	priv->can.clock.freq = 80 * MEGA /* Hz */;
+	priv->can.fd.data_bittiming_const = &dummyxl_fd_databittiming_const;
+	priv->can.fd.tdc_const = &dummyxl_fd_tdc_const;
+	priv->can.xl.data_bittiming_const = &dummyxl_xl_databittiming_const;
+	priv->can.xl.tdc_const = &dummyxl_xl_tdc_const;
+	priv->can.ctrlmode_supported = CAN_CTRLMODE_LISTENONLY |
+		CAN_CTRLMODE_FD | CAN_CTRLMODE_TDC_AUTO |
+		CAN_CTRLMODE_XL | CAN_CTRLMODE_XL_TDC_AUTO;
+	priv->dev = dev;
+
+	ret = register_candev(priv->dev);
+	if (ret) {
+		free_candev(priv->dev);
+		return ret;
+	}
+
+	dummyxl = priv;
+	netdev_info(dev, "dummyxl OK\n");
+
+	return 0;
+}
+
+static void __exit dummyxl_exit(void)
+{
+	struct net_device *dev = dummyxl->dev;
+
+	netdev_info(dev, "dummyxl bye bye\n");
+	unregister_candev(dev);
+	free_candev(dev);
+}
+
+module_init(dummyxl_init);
+module_exit(dummyxl_exit);
+
+MODULE_DESCRIPTION("A dummy module just to check the CAN XL netlink interface");
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Vincent Mailhol <mailhol.vincent@wanadoo.fr>");
-- 
2.45.2