Commit 36d007c6 authored by Stephane Grosjean's avatar Stephane Grosjean Committed by Marc Kleine-Budde
Browse files

can: peak_usb: add ethtool interface to user-configurable CAN channel identifier 



This patch introduces 3 new functions implementing support for ethtool
access to the CAN channel ID of all USB CAN network interfaces managed by
the driver. With this patch, it is possible to read/write the CAN
channel ID from/to the EEPROM via the ethtool interface.

The CAN channel ID is a user-configurable device identifier that can be
set individually for each CAN interface of a PEAK USB device. Depending on
the device, the identifier has a length of 8 or 32 bit. The identifier
is stored in the non-volatile memory of the device.

The identifier of a CAN interface can be read/written as an 8 or 32 bit
byte string in native (little-endian) byte order, where the length depends
on the device type.

Signed-off-by: default avatarStephane Grosjean <s.grosjean@peak-system.com>
Signed-off-by: default avatarLukas Magel <lukas.magel@posteo.net>
Link: https://lore.kernel.org/all/20230116200932.157769-6-lukas.magel@posteo.net


Signed-off-by: default avatarMarc Kleine-Budde <mkl@pengutronix.de>
parent e1bd8822

drivers/net/can/usb/peak_usb/pcan_usb.c

+9 −0
Original line number Diff line number Diff line
@@ -982,9 +982,18 @@ static int pcan_usb_set_phys_id(struct net_device *netdev, 
	return err;

}



/* This device only handles 8-bit CAN channel id. */

static int pcan_usb_get_eeprom_len(struct net_device *netdev)

{

	return sizeof(u8);

}



static const struct ethtool_ops pcan_usb_ethtool_ops = {

	.set_phys_id = pcan_usb_set_phys_id,

	.get_ts_info = pcan_get_ts_info,

	.get_eeprom_len	= pcan_usb_get_eeprom_len,

	.get_eeprom = peak_usb_get_eeprom,

	.set_eeprom = peak_usb_set_eeprom,

};



/*

drivers/net/can/usb/peak_usb/pcan_usb_core.c

+80 −0
Original line number Diff line number Diff line
@@ -808,6 +808,86 @@ static const struct net_device_ops peak_usb_netdev_ops = { 
	.ndo_change_mtu = can_change_mtu,

};



/* CAN-USB devices generally handle 32-bit CAN channel IDs.

 * In case one doesn't, then it have to overload this function.

 */

int peak_usb_get_eeprom_len(struct net_device *netdev)

{

	return sizeof(u32);

}



/* Every CAN-USB device exports the dev_get_can_channel_id() operation. It is used

 * here to fill the data buffer with the user defined CAN channel ID.

 */

int peak_usb_get_eeprom(struct net_device *netdev,

			struct ethtool_eeprom *eeprom, u8 *data)

{

	struct peak_usb_device *dev = netdev_priv(netdev);

	u32 ch_id;

	__le32 ch_id_le;

	int err;



	err = dev->adapter->dev_get_can_channel_id(dev, &ch_id);

	if (err)

		return err;



	/* ethtool operates on individual bytes. The byte order of the CAN

	 * channel id in memory depends on the kernel architecture. We

	 * convert the CAN channel id back to the native byte order of the PEAK

	 * device itself to ensure that the order is consistent for all

	 * host architectures.

	 */

	ch_id_le = cpu_to_le32(ch_id);

	memcpy(data, (u8 *)&ch_id_le + eeprom->offset, eeprom->len);



	/* update cached value */

	dev->can_channel_id = ch_id;

	return err;

}



/* Every CAN-USB device exports the dev_get_can_channel_id()/dev_set_can_channel_id()

 * operations. They are used here to set the new user defined CAN channel ID.

 */

int peak_usb_set_eeprom(struct net_device *netdev,

			struct ethtool_eeprom *eeprom, u8 *data)

{

	struct peak_usb_device *dev = netdev_priv(netdev);

	u32 ch_id;

	__le32 ch_id_le;

	int err;



	/* first, read the current user defined CAN channel ID */

	err = dev->adapter->dev_get_can_channel_id(dev, &ch_id);

	if (err) {

		netdev_err(netdev, "Failed to init CAN channel id (err %d)\n", err);

		return err;

	}



	/* do update the value with user given bytes.

	 * ethtool operates on individual bytes. The byte order of the CAN

	 * channel ID in memory depends on the kernel architecture. We

	 * convert the CAN channel ID back to the native byte order of the PEAK

	 * device itself to ensure that the order is consistent for all

	 * host architectures.

	 */

	ch_id_le = cpu_to_le32(ch_id);

	memcpy((u8 *)&ch_id_le + eeprom->offset, data, eeprom->len);

	ch_id = le32_to_cpu(ch_id_le);



	/* flash the new value now */

	err = dev->adapter->dev_set_can_channel_id(dev, ch_id);

	if (err) {

		netdev_err(netdev, "Failed to write new CAN channel id (err %d)\n",

			   err);

		return err;

	}



	/* update cached value with the new one */

	dev->can_channel_id = ch_id;



	return 0;

}



int pcan_get_ts_info(struct net_device *dev, struct ethtool_ts_info *info)

{

	info->so_timestamping =

drivers/net/can/usb/peak_usb/pcan_usb_core.h

+6 −0
Original line number Diff line number Diff line
@@ -149,4 +149,10 @@ void peak_usb_async_complete(struct urb *urb); 
void peak_usb_restart_complete(struct peak_usb_device *dev);

int pcan_get_ts_info(struct net_device *dev, struct ethtool_ts_info *info);



/* common 32-bit CAN channel ID ethtool management */

int peak_usb_get_eeprom_len(struct net_device *netdev);

int peak_usb_get_eeprom(struct net_device *netdev,

			struct ethtool_eeprom *eeprom, u8 *data);

int peak_usb_set_eeprom(struct net_device *netdev,

			struct ethtool_eeprom *eeprom, u8 *data);

#endif

drivers/net/can/usb/peak_usb/pcan_usb_fd.c

+3 −0
Original line number Diff line number Diff line
@@ -1124,6 +1124,9 @@ static int pcan_usb_fd_set_phys_id(struct net_device *netdev, 
static const struct ethtool_ops pcan_usb_fd_ethtool_ops = {

	.set_phys_id = pcan_usb_fd_set_phys_id,

	.get_ts_info = pcan_get_ts_info,

	.get_eeprom_len	= peak_usb_get_eeprom_len,

	.get_eeprom = peak_usb_get_eeprom,

	.set_eeprom = peak_usb_set_eeprom,

};



/* describes the PCAN-USB FD adapter */

drivers/net/can/usb/peak_usb/pcan_usb_pro.c

+3 −0
Original line number Diff line number Diff line
@@ -1037,6 +1037,9 @@ static int pcan_usb_pro_set_phys_id(struct net_device *netdev, 
static const struct ethtool_ops pcan_usb_pro_ethtool_ops = {

	.set_phys_id = pcan_usb_pro_set_phys_id,

	.get_ts_info = pcan_get_ts_info,

	.get_eeprom_len	= peak_usb_get_eeprom_len,

	.get_eeprom = peak_usb_get_eeprom,

	.set_eeprom = peak_usb_set_eeprom,

};



/*