/* * CAN bus driver for Bosch C_CAN controller * * Copyright (C) 2010 ST Microelectronics * Bhupesh Sharma <[email protected]> * * Borrowed heavily from the C_CAN driver originally written by: * Copyright (C) 2007 * - Sascha Hauer, Marc Kleine-Budde, Pengutronix <[email protected]> * - Simon Kallweit, intefo AG <[email protected]> * * TX and RX NAPI implementation has been borrowed from at91 CAN driver * written by: * Copyright * (C) 2007 by Hans J. Koch <[email protected]> * (C) 2008, 2009 by Marc Kleine-Budde <[email protected]> * * Bosch C_CAN controller is compliant to CAN protocol version 2.0 part A and B. * Bosch C_CAN user manual can be obtained from: * http://www.semiconductors.bosch.de/media/en/pdf/ipmodules_1/c_can/ * users_manual_c_can.pdf * * This file is licensed under the terms of the GNU General Public * License version 2. This program is licensed "as is" without any * warranty of any kind, whether express or implied. */ #include <linux/kernel.h> #include <linux/module.h> #include <linux/interrupt.h> #include <linux/delay.h> #include <linux/netdevice.h> #include <linux/if_arp.h> #include <linux/if_ether.h> #include <linux/list.h> #include <linux/io.h> #include <linux/pm_runtime.h> #include <linux/pinctrl/consumer.h> #include <linux/can.h> #include <linux/can/dev.h> #include <linux/can/error.h> #include "c_can.h" /* Number of interface registers */ #define IF_ENUM_REG_LEN … #define C_CAN_IFACE(reg, iface) … /* control extension register D_CAN specific */ #define CONTROL_EX_PDR … /* control register */ #define CONTROL_SWR … #define CONTROL_TEST … #define CONTROL_CCE … #define CONTROL_DISABLE_AR … #define CONTROL_ENABLE_AR … #define CONTROL_EIE … #define CONTROL_SIE … #define CONTROL_IE … #define CONTROL_INIT … #define CONTROL_IRQMSK … /* test register */ #define TEST_RX … #define TEST_TX1 … #define TEST_TX2 … #define TEST_LBACK … #define TEST_SILENT … #define TEST_BASIC … /* status register */ #define STATUS_PDA … #define STATUS_BOFF … #define STATUS_EWARN … #define STATUS_EPASS … #define STATUS_RXOK … #define STATUS_TXOK … /* error counter register */ #define ERR_CNT_TEC_MASK … #define ERR_CNT_TEC_SHIFT … #define ERR_CNT_REC_SHIFT … #define ERR_CNT_REC_MASK … #define ERR_CNT_RP_SHIFT … #define ERR_CNT_RP_MASK … /* bit-timing register */ #define BTR_BRP_MASK … #define BTR_BRP_SHIFT … #define BTR_SJW_SHIFT … #define BTR_SJW_MASK … #define BTR_TSEG1_SHIFT … #define BTR_TSEG1_MASK … #define BTR_TSEG2_SHIFT … #define BTR_TSEG2_MASK … /* interrupt register */ #define INT_STS_PENDING … /* brp extension register */ #define BRP_EXT_BRPE_MASK … #define BRP_EXT_BRPE_SHIFT … /* IFx command request */ #define IF_COMR_BUSY … /* IFx command mask */ #define IF_COMM_WR … #define IF_COMM_MASK … #define IF_COMM_ARB … #define IF_COMM_CONTROL … #define IF_COMM_CLR_INT_PND … #define IF_COMM_TXRQST … #define IF_COMM_CLR_NEWDAT … #define IF_COMM_DATAA … #define IF_COMM_DATAB … /* TX buffer setup */ #define IF_COMM_TX … /* For the low buffers we clear the interrupt bit, but keep newdat */ #define IF_COMM_RCV_LOW … /* For the high buffers we clear the interrupt bit and newdat */ #define IF_COMM_RCV_HIGH … /* Receive setup of message objects */ #define IF_COMM_RCV_SETUP … /* Invalidation of message objects */ #define IF_COMM_INVAL … /* IFx arbitration */ #define IF_ARB_MSGVAL … #define IF_ARB_MSGXTD … #define IF_ARB_TRANSMIT … /* IFx message control */ #define IF_MCONT_NEWDAT … #define IF_MCONT_MSGLST … #define IF_MCONT_INTPND … #define IF_MCONT_UMASK … #define IF_MCONT_TXIE … #define IF_MCONT_RXIE … #define IF_MCONT_RMTEN … #define IF_MCONT_TXRQST … #define IF_MCONT_EOB … #define IF_MCONT_DLC_MASK … #define IF_MCONT_RCV … #define IF_MCONT_RCV_EOB … #define IF_MCONT_TX … /* Use IF1 in NAPI path and IF2 in TX path */ #define IF_NAPI … #define IF_TX … /* minimum timeout for checking BUSY status */ #define MIN_TIMEOUT_VALUE … /* Wait for ~1 sec for INIT bit */ #define INIT_WAIT_MS … /* c_can lec values */ enum c_can_lec_type { … }; /* c_can error types: * Bus errors (BUS_OFF, ERROR_WARNING, ERROR_PASSIVE) are supported */ enum c_can_bus_error_types { … }; static const struct can_bittiming_const c_can_bittiming_const = …; static inline void c_can_pm_runtime_get_sync(const struct c_can_priv *priv) { … } static inline void c_can_pm_runtime_put_sync(const struct c_can_priv *priv) { … } static inline void c_can_reset_ram(const struct c_can_priv *priv, bool enable) { … } static void c_can_irq_control(struct c_can_priv *priv, bool enable) { … } static void c_can_obj_update(struct net_device *dev, int iface, u32 cmd, u32 obj) { … } static inline void c_can_object_get(struct net_device *dev, int iface, u32 obj, u32 cmd) { … } static inline void c_can_object_put(struct net_device *dev, int iface, u32 obj, u32 cmd) { … } /* Note: According to documentation clearing TXIE while MSGVAL is set * is not allowed, but works nicely on C/DCAN. And that lowers the I/O * load significantly. */ static void c_can_inval_tx_object(struct net_device *dev, int iface, int obj) { … } static void c_can_inval_msg_object(struct net_device *dev, int iface, int obj) { … } static void c_can_setup_tx_object(struct net_device *dev, int iface, struct can_frame *frame, int idx) { … } static int c_can_handle_lost_msg_obj(struct net_device *dev, int iface, int objno, u32 ctrl) { … } static int c_can_read_msg_object(struct net_device *dev, int iface, u32 ctrl) { … } static void c_can_setup_receive_object(struct net_device *dev, int iface, u32 obj, u32 mask, u32 id, u32 mcont) { … } static bool c_can_tx_busy(const struct c_can_priv *priv, const struct c_can_tx_ring *tx_ring) { … } static netdev_tx_t c_can_start_xmit(struct sk_buff *skb, struct net_device *dev) { … } static int c_can_wait_for_ctrl_init(struct net_device *dev, struct c_can_priv *priv, u32 init) { … } static int c_can_set_bittiming(struct net_device *dev) { … } /* Configure C_CAN message objects for Tx and Rx purposes: * C_CAN provides a total of 32 message objects that can be configured * either for Tx or Rx purposes. Here the first 16 message objects are used as * a reception FIFO. The end of reception FIFO is signified by the EoB bit * being SET. The remaining 16 message objects are kept aside for Tx purposes. * See user guide document for further details on configuring message * objects. */ static void c_can_configure_msg_objects(struct net_device *dev) { … } static int c_can_software_reset(struct net_device *dev) { … } /* Configure C_CAN chip: * - enable/disable auto-retransmission * - set operating mode * - configure message objects */ static int c_can_chip_config(struct net_device *dev) { … } static int c_can_start(struct net_device *dev) { … } static void c_can_stop(struct net_device *dev) { … } static int c_can_set_mode(struct net_device *dev, enum can_mode mode) { … } static int __c_can_get_berr_counter(const struct net_device *dev, struct can_berr_counter *bec) { … } static int c_can_get_berr_counter(const struct net_device *dev, struct can_berr_counter *bec) { … } static void c_can_do_tx(struct net_device *dev) { … } /* If we have a gap in the pending bits, that means we either * raced with the hardware or failed to readout all upper * objects in the last run due to quota limit. */ static u32 c_can_adjust_pending(u32 pend, u32 rx_mask) { … } static inline void c_can_rx_object_get(struct net_device *dev, struct c_can_priv *priv, u32 obj) { … } static inline void c_can_rx_finalize(struct net_device *dev, struct c_can_priv *priv, u32 obj) { … } static int c_can_read_objects(struct net_device *dev, struct c_can_priv *priv, u32 pend, int quota) { … } static inline u32 c_can_get_pending(struct c_can_priv *priv) { … } /* theory of operation: * * c_can core saves a received CAN message into the first free message * object it finds free (starting with the lowest). Bits NEWDAT and * INTPND are set for this message object indicating that a new message * has arrived. * * We clear the newdat bit right away. * * This can result in packet reordering when the readout is slow. */ static int c_can_do_rx_poll(struct net_device *dev, int quota) { … } static int c_can_handle_state_change(struct net_device *dev, enum c_can_bus_error_types error_type) { … } static int c_can_handle_bus_err(struct net_device *dev, enum c_can_lec_type lec_type) { … } static int c_can_poll(struct napi_struct *napi, int quota) { … } static irqreturn_t c_can_isr(int irq, void *dev_id) { … } static int c_can_open(struct net_device *dev) { … } static int c_can_close(struct net_device *dev) { … } struct net_device *alloc_c_can_dev(int msg_obj_num) { … } EXPORT_SYMBOL_GPL(…); #ifdef CONFIG_PM int c_can_power_down(struct net_device *dev) { … } EXPORT_SYMBOL_GPL(…); int c_can_power_up(struct net_device *dev) { … } EXPORT_SYMBOL_GPL(…); #endif void free_c_can_dev(struct net_device *dev) { … } EXPORT_SYMBOL_GPL(…); static const struct net_device_ops c_can_netdev_ops = …; int register_c_can_dev(struct net_device *dev) { … } EXPORT_SYMBOL_GPL(…); void unregister_c_can_dev(struct net_device *dev) { … } EXPORT_SYMBOL_GPL(…); MODULE_AUTHOR(…) …; MODULE_LICENSE(…) …; MODULE_DESCRIPTION(…) …;
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