Merge tag 'linux-can-next-for-5.11-20201120' of git://git.kernel.org/pub/scm/linux/kernel/git/mkl/linux-can-next

Marc Kleine-Budde says:

====================
pull-request: can-next 2020-11-20

The first patch is by Yegor Yefremov and he improves the j1939 documentaton by
adding tables for the CAN identifier and its fields.

Then there are 8 patches by Oliver Hartkopp targeting the CAN driver
infrastructure and drivers. These add support for optional DLC element to the
Classical CAN frame structure. See patch ea7800565a12 ("can: add optional DLC
element to Classical CAN frame structure") for details. Oliver's last patch
adds len8_dlc support to several drivers. Stefan Mätje provides a patch to add
len8_dlc support to the esd_usb2 driver.

The next patch is by Oliver Hartkopp, too and adds support for modification of
Classical CAN DLCs to CAN GW sockets.

The next 3 patches target the nxp,flexcan DT bindings. One patch by my adds the
missing uint32 reference to the clock-frequency property. Joakim Zhang's
patches fix the fsl,clk-source property and add the IMX_SC_R_CAN() macro to the
imx firmware header file, which will be used in the flexcan driver later.

Another patch by Joakim Zhang prepares the flexcan driver for SCU based
stop-mode, by giving the existing, GPR based stop-mode, a _GPR postfix.

The next 5 patches are by me, target the flexcan driver, and clean up the
.ndo_open and .ndo_stop callbacks. These patches try to fix a sporadically
hanging flexcan_close() during simultanious ifdown, sending of CAN messages and
probably open CAN bus. I was never able to reproduce, but these seem to fix the
problem at the reporting user. As these changes are rather big, I'd like to
mainline them via net-next/master.

The next patches are by Jimmy Assarsson and Christer Beskow, they add support
for new USB devices to the existing kvaser_usb driver.

The last patch is by Kaixu Xia and simplifies the return in the
mcp251xfd_chip_softreset() function in the mcp251xfd driver.

* tag 'linux-can-next-for-5.11-20201120' of git://git.kernel.org/pub/scm/linux/kernel/git/mkl/linux-can-next: (25 commits)
  can: mcp251xfd: remove useless code in mcp251xfd_chip_softreset
  can: kvaser_usb: Add new Kvaser hydra devices
  can: kvaser_usb: kvaser_usb_hydra: Add support for new device variant
  can: kvaser_usb: Add new Kvaser Leaf v2 devices
  can: kvaser_usb: Add USB_{LEAF,HYDRA}_PRODUCT_ID_END defines
  can: flexcan: flexcan_close(): change order if commands to properly shut down the controller
  can: flexcan: flexcan_open(): completely initialize controller before requesting IRQ
  can: flexcan: flexcan_rx_offload_setup(): factor out mailbox and rx-offload setup into separate function
  can: flexcan: move enabling/disabling of interrupts from flexcan_chip_{start,stop}() to callers
  can: flexcan: factor out enabling and disabling of interrupts into separate function
  can: flexcan: rename macro FLEXCAN_QUIRK_SETUP_STOP_MODE -> FLEXCAN_QUIRK_SETUP_STOP_MODE_GPR
  dt-bindings: firmware: add IMX_SC_R_CAN(x) macro for CAN
  dt-bindings: can: fsl,flexcan: fix fsl,clk-source property
  dt-bindings: can: fsl,flexcan: add uint32 reference to clock-frequency property
  can: gw: support modification of Classical CAN DLCs
  can: drivers: add len8_dlc support for esd_usb2 CAN adapter
  can: drivers: add len8_dlc support for various CAN adapters
  can: drivers: introduce helpers to access Classical CAN DLC values
  can: update documentation for DLC usage in Classical CAN
  can: rename CAN FD related can_len2dlc and can_dlc2len helpers
  ...
====================

Link: https://lore.kernel.org/r/20201120133318.3428231-1-mkl@pengutronix.de
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

3 files changed, 27 insertions, 16 deletions

diff --git a/include/uapi/linux/can.h b/include/uapi/linux/can.h
index 6a6d2c7655ff..f75238ac6dce 100644
--- a/include/uapi/linux/can.h
+++ b/include/uapi/linux/can.h
@@ -84,6 +84,7 @@ typedef __u32 can_err_mask_t;
 
 /* CAN payload length and DLC definitions according to ISO 11898-1 */
 #define CAN_MAX_DLC 8
+#define CAN_MAX_RAW_DLC 15
 #define CAN_MAX_DLEN 8
 
 /* CAN FD payload length and DLC definitions according to ISO 11898-7 */
@@ -91,23 +92,32 @@ typedef __u32 can_err_mask_t;
 #define CANFD_MAX_DLEN 64
 
 /**
- * struct can_frame - basic CAN frame structure
- * @can_id:  CAN ID of the frame and CAN_*_FLAG flags, see canid_t definition
- * @can_dlc: frame payload length in byte (0 .. 8) aka data length code
- *           N.B. the DLC field from ISO 11898-1 Chapter 8.4.2.3 has a 1:1
- *           mapping of the 'data length code' to the real payload length
- * @__pad:   padding
- * @__res0:  reserved / padding
- * @__res1:  reserved / padding
- * @data:    CAN frame payload (up to 8 byte)
+ * struct can_frame - Classical CAN frame structure (aka CAN 2.0B)
+ * @can_id:   CAN ID of the frame and CAN_*_FLAG flags, see canid_t definition
+ * @len:      CAN frame payload length in byte (0 .. 8)
+ * @can_dlc:  deprecated name for CAN frame payload length in byte (0 .. 8)
+ * @__pad:    padding
+ * @__res0:   reserved / padding
+ * @len8_dlc: optional DLC value (9 .. 15) at 8 byte payload length
+ *            len8_dlc contains values from 9 .. 15 when the payload length is
+ *            8 bytes but the DLC value (see ISO 11898-1) is greater then 8.
+ *            CAN_CTRLMODE_CC_LEN8_DLC flag has to be enabled in CAN driver.
+ * @data:     CAN frame payload (up to 8 byte)
  */
 struct can_frame {
 	canid_t can_id;  /* 32 bit CAN_ID + EFF/RTR/ERR flags */
-	__u8    can_dlc; /* frame payload length in byte (0 .. CAN_MAX_DLEN) */
-	__u8    __pad;   /* padding */
-	__u8    __res0;  /* reserved / padding */
-	__u8    __res1;  /* reserved / padding */
-	__u8    data[CAN_MAX_DLEN] __attribute__((aligned(8)));
+	union {
+		/* CAN frame payload length in byte (0 .. CAN_MAX_DLEN)
+		 * was previously named can_dlc so we need to carry that
+		 * name for legacy support
+		 */
+		__u8 len;
+		__u8 can_dlc; /* deprecated */
+	};
+	__u8 __pad; /* padding */
+	__u8 __res0; /* reserved / padding */
+	__u8 len8_dlc; /* optional DLC for 8 byte payload length (9 .. 15) */
+	__u8 data[CAN_MAX_DLEN] __attribute__((aligned(8)));
 };
 
 /*
diff --git a/include/uapi/linux/can/gw.h b/include/uapi/linux/can/gw.h
index c2190bbe21d8..e4f0957554f3 100644
--- a/include/uapi/linux/can/gw.h
+++ b/include/uapi/linux/can/gw.h
@@ -98,8 +98,8 @@ enum {
 
 /* CAN frame elements that are affected by curr. 3 CAN frame modifications */
 #define CGW_MOD_ID	0x01
-#define CGW_MOD_DLC	0x02		/* contains the data length in bytes */
-#define CGW_MOD_LEN	CGW_MOD_DLC	/* CAN FD length representation */
+#define CGW_MOD_DLC	0x02		/* Classical CAN data length code */
+#define CGW_MOD_LEN	CGW_MOD_DLC	/* CAN FD (plain) data length */
 #define CGW_MOD_DATA	0x04
 #define CGW_MOD_FLAGS	0x08		/* CAN FD flags */
 
diff --git a/include/uapi/linux/can/netlink.h b/include/uapi/linux/can/netlink.h
index 6f598b73839e..f730d443b918 100644
--- a/include/uapi/linux/can/netlink.h
+++ b/include/uapi/linux/can/netlink.h
@@ -100,6 +100,7 @@ struct can_ctrlmode {
 #define CAN_CTRLMODE_FD			0x20	/* CAN FD mode */
 #define CAN_CTRLMODE_PRESUME_ACK	0x40	/* Ignore missing CAN ACKs */
 #define CAN_CTRLMODE_FD_NON_ISO		0x80	/* CAN FD in non-ISO mode */
+#define CAN_CTRLMODE_CC_LEN8_DLC	0x100	/* Classic CAN DLC option */
 
 /*
  * CAN device statistics