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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-11 08:27:49 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-11 08:27:49 +0000 |
commit | ace9429bb58fd418f0c81d4c2835699bddf6bde6 (patch) | |
tree | b2d64bc10158fdd5497876388cd68142ca374ed3 /drivers/net/can/m_can/m_can.c | |
parent | Initial commit. (diff) | |
download | linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.tar.xz linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.zip |
Adding upstream version 6.6.15.upstream/6.6.15
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/net/can/m_can/m_can.c')
-rw-r--r-- | drivers/net/can/m_can/m_can.c | 2169 |
1 files changed, 2169 insertions, 0 deletions
diff --git a/drivers/net/can/m_can/m_can.c b/drivers/net/can/m_can/m_can.c new file mode 100644 index 0000000000..16ecc11c7f --- /dev/null +++ b/drivers/net/can/m_can/m_can.c @@ -0,0 +1,2169 @@ +// SPDX-License-Identifier: GPL-2.0 +// CAN bus driver for Bosch M_CAN controller +// Copyright (C) 2014 Freescale Semiconductor, Inc. +// Dong Aisheng <b29396@freescale.com> +// Copyright (C) 2018-19 Texas Instruments Incorporated - http://www.ti.com/ + +/* Bosch M_CAN user manual can be obtained from: + * https://github.com/linux-can/can-doc/tree/master/m_can + */ + +#include <linux/bitfield.h> +#include <linux/can/dev.h> +#include <linux/ethtool.h> +#include <linux/hrtimer.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/iopoll.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/netdevice.h> +#include <linux/of.h> +#include <linux/phy/phy.h> +#include <linux/pinctrl/consumer.h> +#include <linux/platform_device.h> +#include <linux/pm_runtime.h> + +#include "m_can.h" + +/* registers definition */ +enum m_can_reg { + M_CAN_CREL = 0x0, + M_CAN_ENDN = 0x4, + M_CAN_CUST = 0x8, + M_CAN_DBTP = 0xc, + M_CAN_TEST = 0x10, + M_CAN_RWD = 0x14, + M_CAN_CCCR = 0x18, + M_CAN_NBTP = 0x1c, + M_CAN_TSCC = 0x20, + M_CAN_TSCV = 0x24, + M_CAN_TOCC = 0x28, + M_CAN_TOCV = 0x2c, + M_CAN_ECR = 0x40, + M_CAN_PSR = 0x44, + /* TDCR Register only available for version >=3.1.x */ + M_CAN_TDCR = 0x48, + M_CAN_IR = 0x50, + M_CAN_IE = 0x54, + M_CAN_ILS = 0x58, + M_CAN_ILE = 0x5c, + M_CAN_GFC = 0x80, + M_CAN_SIDFC = 0x84, + M_CAN_XIDFC = 0x88, + M_CAN_XIDAM = 0x90, + M_CAN_HPMS = 0x94, + M_CAN_NDAT1 = 0x98, + M_CAN_NDAT2 = 0x9c, + M_CAN_RXF0C = 0xa0, + M_CAN_RXF0S = 0xa4, + M_CAN_RXF0A = 0xa8, + M_CAN_RXBC = 0xac, + M_CAN_RXF1C = 0xb0, + M_CAN_RXF1S = 0xb4, + M_CAN_RXF1A = 0xb8, + M_CAN_RXESC = 0xbc, + M_CAN_TXBC = 0xc0, + M_CAN_TXFQS = 0xc4, + M_CAN_TXESC = 0xc8, + M_CAN_TXBRP = 0xcc, + M_CAN_TXBAR = 0xd0, + M_CAN_TXBCR = 0xd4, + M_CAN_TXBTO = 0xd8, + M_CAN_TXBCF = 0xdc, + M_CAN_TXBTIE = 0xe0, + M_CAN_TXBCIE = 0xe4, + M_CAN_TXEFC = 0xf0, + M_CAN_TXEFS = 0xf4, + M_CAN_TXEFA = 0xf8, +}; + +/* message ram configuration data length */ +#define MRAM_CFG_LEN 8 + +/* Core Release Register (CREL) */ +#define CREL_REL_MASK GENMASK(31, 28) +#define CREL_STEP_MASK GENMASK(27, 24) +#define CREL_SUBSTEP_MASK GENMASK(23, 20) + +/* Data Bit Timing & Prescaler Register (DBTP) */ +#define DBTP_TDC BIT(23) +#define DBTP_DBRP_MASK GENMASK(20, 16) +#define DBTP_DTSEG1_MASK GENMASK(12, 8) +#define DBTP_DTSEG2_MASK GENMASK(7, 4) +#define DBTP_DSJW_MASK GENMASK(3, 0) + +/* Transmitter Delay Compensation Register (TDCR) */ +#define TDCR_TDCO_MASK GENMASK(14, 8) +#define TDCR_TDCF_MASK GENMASK(6, 0) + +/* Test Register (TEST) */ +#define TEST_LBCK BIT(4) + +/* CC Control Register (CCCR) */ +#define CCCR_TXP BIT(14) +#define CCCR_TEST BIT(7) +#define CCCR_DAR BIT(6) +#define CCCR_MON BIT(5) +#define CCCR_CSR BIT(4) +#define CCCR_CSA BIT(3) +#define CCCR_ASM BIT(2) +#define CCCR_CCE BIT(1) +#define CCCR_INIT BIT(0) +/* for version 3.0.x */ +#define CCCR_CMR_MASK GENMASK(11, 10) +#define CCCR_CMR_CANFD 0x1 +#define CCCR_CMR_CANFD_BRS 0x2 +#define CCCR_CMR_CAN 0x3 +#define CCCR_CME_MASK GENMASK(9, 8) +#define CCCR_CME_CAN 0 +#define CCCR_CME_CANFD 0x1 +#define CCCR_CME_CANFD_BRS 0x2 +/* for version >=3.1.x */ +#define CCCR_EFBI BIT(13) +#define CCCR_PXHD BIT(12) +#define CCCR_BRSE BIT(9) +#define CCCR_FDOE BIT(8) +/* for version >=3.2.x */ +#define CCCR_NISO BIT(15) +/* for version >=3.3.x */ +#define CCCR_WMM BIT(11) +#define CCCR_UTSU BIT(10) + +/* Nominal Bit Timing & Prescaler Register (NBTP) */ +#define NBTP_NSJW_MASK GENMASK(31, 25) +#define NBTP_NBRP_MASK GENMASK(24, 16) +#define NBTP_NTSEG1_MASK GENMASK(15, 8) +#define NBTP_NTSEG2_MASK GENMASK(6, 0) + +/* Timestamp Counter Configuration Register (TSCC) */ +#define TSCC_TCP_MASK GENMASK(19, 16) +#define TSCC_TSS_MASK GENMASK(1, 0) +#define TSCC_TSS_DISABLE 0x0 +#define TSCC_TSS_INTERNAL 0x1 +#define TSCC_TSS_EXTERNAL 0x2 + +/* Timestamp Counter Value Register (TSCV) */ +#define TSCV_TSC_MASK GENMASK(15, 0) + +/* Error Counter Register (ECR) */ +#define ECR_RP BIT(15) +#define ECR_REC_MASK GENMASK(14, 8) +#define ECR_TEC_MASK GENMASK(7, 0) + +/* Protocol Status Register (PSR) */ +#define PSR_BO BIT(7) +#define PSR_EW BIT(6) +#define PSR_EP BIT(5) +#define PSR_LEC_MASK GENMASK(2, 0) +#define PSR_DLEC_MASK GENMASK(10, 8) + +/* Interrupt Register (IR) */ +#define IR_ALL_INT 0xffffffff + +/* Renamed bits for versions > 3.1.x */ +#define IR_ARA BIT(29) +#define IR_PED BIT(28) +#define IR_PEA BIT(27) + +/* Bits for version 3.0.x */ +#define IR_STE BIT(31) +#define IR_FOE BIT(30) +#define IR_ACKE BIT(29) +#define IR_BE BIT(28) +#define IR_CRCE BIT(27) +#define IR_WDI BIT(26) +#define IR_BO BIT(25) +#define IR_EW BIT(24) +#define IR_EP BIT(23) +#define IR_ELO BIT(22) +#define IR_BEU BIT(21) +#define IR_BEC BIT(20) +#define IR_DRX BIT(19) +#define IR_TOO BIT(18) +#define IR_MRAF BIT(17) +#define IR_TSW BIT(16) +#define IR_TEFL BIT(15) +#define IR_TEFF BIT(14) +#define IR_TEFW BIT(13) +#define IR_TEFN BIT(12) +#define IR_TFE BIT(11) +#define IR_TCF BIT(10) +#define IR_TC BIT(9) +#define IR_HPM BIT(8) +#define IR_RF1L BIT(7) +#define IR_RF1F BIT(6) +#define IR_RF1W BIT(5) +#define IR_RF1N BIT(4) +#define IR_RF0L BIT(3) +#define IR_RF0F BIT(2) +#define IR_RF0W BIT(1) +#define IR_RF0N BIT(0) +#define IR_ERR_STATE (IR_BO | IR_EW | IR_EP) + +/* Interrupts for version 3.0.x */ +#define IR_ERR_LEC_30X (IR_STE | IR_FOE | IR_ACKE | IR_BE | IR_CRCE) +#define IR_ERR_BUS_30X (IR_ERR_LEC_30X | IR_WDI | IR_BEU | IR_BEC | \ + IR_TOO | IR_MRAF | IR_TSW | IR_TEFL | IR_RF1L | \ + IR_RF0L) +#define IR_ERR_ALL_30X (IR_ERR_STATE | IR_ERR_BUS_30X) + +/* Interrupts for version >= 3.1.x */ +#define IR_ERR_LEC_31X (IR_PED | IR_PEA) +#define IR_ERR_BUS_31X (IR_ERR_LEC_31X | IR_WDI | IR_BEU | IR_BEC | \ + IR_TOO | IR_MRAF | IR_TSW | IR_TEFL | IR_RF1L | \ + IR_RF0L) +#define IR_ERR_ALL_31X (IR_ERR_STATE | IR_ERR_BUS_31X) + +/* Interrupt Line Select (ILS) */ +#define ILS_ALL_INT0 0x0 +#define ILS_ALL_INT1 0xFFFFFFFF + +/* Interrupt Line Enable (ILE) */ +#define ILE_EINT1 BIT(1) +#define ILE_EINT0 BIT(0) + +/* Rx FIFO 0/1 Configuration (RXF0C/RXF1C) */ +#define RXFC_FWM_MASK GENMASK(30, 24) +#define RXFC_FS_MASK GENMASK(22, 16) + +/* Rx FIFO 0/1 Status (RXF0S/RXF1S) */ +#define RXFS_RFL BIT(25) +#define RXFS_FF BIT(24) +#define RXFS_FPI_MASK GENMASK(21, 16) +#define RXFS_FGI_MASK GENMASK(13, 8) +#define RXFS_FFL_MASK GENMASK(6, 0) + +/* Rx Buffer / FIFO Element Size Configuration (RXESC) */ +#define RXESC_RBDS_MASK GENMASK(10, 8) +#define RXESC_F1DS_MASK GENMASK(6, 4) +#define RXESC_F0DS_MASK GENMASK(2, 0) +#define RXESC_64B 0x7 + +/* Tx Buffer Configuration (TXBC) */ +#define TXBC_TFQS_MASK GENMASK(29, 24) +#define TXBC_NDTB_MASK GENMASK(21, 16) + +/* Tx FIFO/Queue Status (TXFQS) */ +#define TXFQS_TFQF BIT(21) +#define TXFQS_TFQPI_MASK GENMASK(20, 16) +#define TXFQS_TFGI_MASK GENMASK(12, 8) +#define TXFQS_TFFL_MASK GENMASK(5, 0) + +/* Tx Buffer Element Size Configuration (TXESC) */ +#define TXESC_TBDS_MASK GENMASK(2, 0) +#define TXESC_TBDS_64B 0x7 + +/* Tx Event FIFO Configuration (TXEFC) */ +#define TXEFC_EFS_MASK GENMASK(21, 16) + +/* Tx Event FIFO Status (TXEFS) */ +#define TXEFS_TEFL BIT(25) +#define TXEFS_EFF BIT(24) +#define TXEFS_EFGI_MASK GENMASK(12, 8) +#define TXEFS_EFFL_MASK GENMASK(5, 0) + +/* Tx Event FIFO Acknowledge (TXEFA) */ +#define TXEFA_EFAI_MASK GENMASK(4, 0) + +/* Message RAM Configuration (in bytes) */ +#define SIDF_ELEMENT_SIZE 4 +#define XIDF_ELEMENT_SIZE 8 +#define RXF0_ELEMENT_SIZE 72 +#define RXF1_ELEMENT_SIZE 72 +#define RXB_ELEMENT_SIZE 72 +#define TXE_ELEMENT_SIZE 8 +#define TXB_ELEMENT_SIZE 72 + +/* Message RAM Elements */ +#define M_CAN_FIFO_ID 0x0 +#define M_CAN_FIFO_DLC 0x4 +#define M_CAN_FIFO_DATA 0x8 + +/* Rx Buffer Element */ +/* R0 */ +#define RX_BUF_ESI BIT(31) +#define RX_BUF_XTD BIT(30) +#define RX_BUF_RTR BIT(29) +/* R1 */ +#define RX_BUF_ANMF BIT(31) +#define RX_BUF_FDF BIT(21) +#define RX_BUF_BRS BIT(20) +#define RX_BUF_RXTS_MASK GENMASK(15, 0) + +/* Tx Buffer Element */ +/* T0 */ +#define TX_BUF_ESI BIT(31) +#define TX_BUF_XTD BIT(30) +#define TX_BUF_RTR BIT(29) +/* T1 */ +#define TX_BUF_EFC BIT(23) +#define TX_BUF_FDF BIT(21) +#define TX_BUF_BRS BIT(20) +#define TX_BUF_MM_MASK GENMASK(31, 24) +#define TX_BUF_DLC_MASK GENMASK(19, 16) + +/* Tx event FIFO Element */ +/* E1 */ +#define TX_EVENT_MM_MASK GENMASK(31, 24) +#define TX_EVENT_TXTS_MASK GENMASK(15, 0) + +/* Hrtimer polling interval */ +#define HRTIMER_POLL_INTERVAL_MS 1 + +/* The ID and DLC registers are adjacent in M_CAN FIFO memory, + * and we can save a (potentially slow) bus round trip by combining + * reads and writes to them. + */ +struct id_and_dlc { + u32 id; + u32 dlc; +}; + +static inline u32 m_can_read(struct m_can_classdev *cdev, enum m_can_reg reg) +{ + return cdev->ops->read_reg(cdev, reg); +} + +static inline void m_can_write(struct m_can_classdev *cdev, enum m_can_reg reg, + u32 val) +{ + cdev->ops->write_reg(cdev, reg, val); +} + +static int +m_can_fifo_read(struct m_can_classdev *cdev, + u32 fgi, unsigned int offset, void *val, size_t val_count) +{ + u32 addr_offset = cdev->mcfg[MRAM_RXF0].off + fgi * RXF0_ELEMENT_SIZE + + offset; + + if (val_count == 0) + return 0; + + return cdev->ops->read_fifo(cdev, addr_offset, val, val_count); +} + +static int +m_can_fifo_write(struct m_can_classdev *cdev, + u32 fpi, unsigned int offset, const void *val, size_t val_count) +{ + u32 addr_offset = cdev->mcfg[MRAM_TXB].off + fpi * TXB_ELEMENT_SIZE + + offset; + + if (val_count == 0) + return 0; + + return cdev->ops->write_fifo(cdev, addr_offset, val, val_count); +} + +static inline int m_can_fifo_write_no_off(struct m_can_classdev *cdev, + u32 fpi, u32 val) +{ + return cdev->ops->write_fifo(cdev, fpi, &val, 1); +} + +static int +m_can_txe_fifo_read(struct m_can_classdev *cdev, u32 fgi, u32 offset, u32 *val) +{ + u32 addr_offset = cdev->mcfg[MRAM_TXE].off + fgi * TXE_ELEMENT_SIZE + + offset; + + return cdev->ops->read_fifo(cdev, addr_offset, val, 1); +} + +static inline bool _m_can_tx_fifo_full(u32 txfqs) +{ + return !!(txfqs & TXFQS_TFQF); +} + +static inline bool m_can_tx_fifo_full(struct m_can_classdev *cdev) +{ + return _m_can_tx_fifo_full(m_can_read(cdev, M_CAN_TXFQS)); +} + +static void m_can_config_endisable(struct m_can_classdev *cdev, bool enable) +{ + u32 cccr = m_can_read(cdev, M_CAN_CCCR); + u32 timeout = 10; + u32 val = 0; + + /* Clear the Clock stop request if it was set */ + if (cccr & CCCR_CSR) + cccr &= ~CCCR_CSR; + + if (enable) { + /* enable m_can configuration */ + m_can_write(cdev, M_CAN_CCCR, cccr | CCCR_INIT); + udelay(5); + /* CCCR.CCE can only be set/reset while CCCR.INIT = '1' */ + m_can_write(cdev, M_CAN_CCCR, cccr | CCCR_INIT | CCCR_CCE); + } else { + m_can_write(cdev, M_CAN_CCCR, cccr & ~(CCCR_INIT | CCCR_CCE)); + } + + /* there's a delay for module initialization */ + if (enable) + val = CCCR_INIT | CCCR_CCE; + + while ((m_can_read(cdev, M_CAN_CCCR) & (CCCR_INIT | CCCR_CCE)) != val) { + if (timeout == 0) { + netdev_warn(cdev->net, "Failed to init module\n"); + return; + } + timeout--; + udelay(1); + } +} + +static inline void m_can_enable_all_interrupts(struct m_can_classdev *cdev) +{ + /* Only interrupt line 0 is used in this driver */ + m_can_write(cdev, M_CAN_ILE, ILE_EINT0); +} + +static inline void m_can_disable_all_interrupts(struct m_can_classdev *cdev) +{ + m_can_write(cdev, M_CAN_ILE, 0x0); +} + +/* Retrieve internal timestamp counter from TSCV.TSC, and shift it to 32-bit + * width. + */ +static u32 m_can_get_timestamp(struct m_can_classdev *cdev) +{ + u32 tscv; + u32 tsc; + + tscv = m_can_read(cdev, M_CAN_TSCV); + tsc = FIELD_GET(TSCV_TSC_MASK, tscv); + + return (tsc << 16); +} + +static void m_can_clean(struct net_device *net) +{ + struct m_can_classdev *cdev = netdev_priv(net); + + if (cdev->tx_skb) { + int putidx = 0; + + net->stats.tx_errors++; + if (cdev->version > 30) + putidx = FIELD_GET(TXFQS_TFQPI_MASK, + m_can_read(cdev, M_CAN_TXFQS)); + + can_free_echo_skb(cdev->net, putidx, NULL); + cdev->tx_skb = NULL; + } +} + +/* For peripherals, pass skb to rx-offload, which will push skb from + * napi. For non-peripherals, RX is done in napi already, so push + * directly. timestamp is used to ensure good skb ordering in + * rx-offload and is ignored for non-peripherals. + */ +static void m_can_receive_skb(struct m_can_classdev *cdev, + struct sk_buff *skb, + u32 timestamp) +{ + if (cdev->is_peripheral) { + struct net_device_stats *stats = &cdev->net->stats; + int err; + + err = can_rx_offload_queue_timestamp(&cdev->offload, skb, + timestamp); + if (err) + stats->rx_fifo_errors++; + } else { + netif_receive_skb(skb); + } +} + +static int m_can_read_fifo(struct net_device *dev, u32 fgi) +{ + struct net_device_stats *stats = &dev->stats; + struct m_can_classdev *cdev = netdev_priv(dev); + struct canfd_frame *cf; + struct sk_buff *skb; + struct id_and_dlc fifo_header; + u32 timestamp = 0; + int err; + + err = m_can_fifo_read(cdev, fgi, M_CAN_FIFO_ID, &fifo_header, 2); + if (err) + goto out_fail; + + if (fifo_header.dlc & RX_BUF_FDF) + skb = alloc_canfd_skb(dev, &cf); + else + skb = alloc_can_skb(dev, (struct can_frame **)&cf); + if (!skb) { + stats->rx_dropped++; + return 0; + } + + if (fifo_header.dlc & RX_BUF_FDF) + cf->len = can_fd_dlc2len((fifo_header.dlc >> 16) & 0x0F); + else + cf->len = can_cc_dlc2len((fifo_header.dlc >> 16) & 0x0F); + + if (fifo_header.id & RX_BUF_XTD) + cf->can_id = (fifo_header.id & CAN_EFF_MASK) | CAN_EFF_FLAG; + else + cf->can_id = (fifo_header.id >> 18) & CAN_SFF_MASK; + + if (fifo_header.id & RX_BUF_ESI) { + cf->flags |= CANFD_ESI; + netdev_dbg(dev, "ESI Error\n"); + } + + if (!(fifo_header.dlc & RX_BUF_FDF) && (fifo_header.id & RX_BUF_RTR)) { + cf->can_id |= CAN_RTR_FLAG; + } else { + if (fifo_header.dlc & RX_BUF_BRS) + cf->flags |= CANFD_BRS; + + err = m_can_fifo_read(cdev, fgi, M_CAN_FIFO_DATA, + cf->data, DIV_ROUND_UP(cf->len, 4)); + if (err) + goto out_free_skb; + + stats->rx_bytes += cf->len; + } + stats->rx_packets++; + + timestamp = FIELD_GET(RX_BUF_RXTS_MASK, fifo_header.dlc) << 16; + + m_can_receive_skb(cdev, skb, timestamp); + + return 0; + +out_free_skb: + kfree_skb(skb); +out_fail: + netdev_err(dev, "FIFO read returned %d\n", err); + return err; +} + +static int m_can_do_rx_poll(struct net_device *dev, int quota) +{ + struct m_can_classdev *cdev = netdev_priv(dev); + u32 pkts = 0; + u32 rxfs; + u32 rx_count; + u32 fgi; + int ack_fgi = -1; + int i; + int err = 0; + + rxfs = m_can_read(cdev, M_CAN_RXF0S); + if (!(rxfs & RXFS_FFL_MASK)) { + netdev_dbg(dev, "no messages in fifo0\n"); + return 0; + } + + rx_count = FIELD_GET(RXFS_FFL_MASK, rxfs); + fgi = FIELD_GET(RXFS_FGI_MASK, rxfs); + + for (i = 0; i < rx_count && quota > 0; ++i) { + err = m_can_read_fifo(dev, fgi); + if (err) + break; + + quota--; + pkts++; + ack_fgi = fgi; + fgi = (++fgi >= cdev->mcfg[MRAM_RXF0].num ? 0 : fgi); + } + + if (ack_fgi != -1) + m_can_write(cdev, M_CAN_RXF0A, ack_fgi); + + if (err) + return err; + + return pkts; +} + +static int m_can_handle_lost_msg(struct net_device *dev) +{ + struct m_can_classdev *cdev = netdev_priv(dev); + struct net_device_stats *stats = &dev->stats; + struct sk_buff *skb; + struct can_frame *frame; + u32 timestamp = 0; + + netdev_err(dev, "msg lost in rxf0\n"); + + stats->rx_errors++; + stats->rx_over_errors++; + + skb = alloc_can_err_skb(dev, &frame); + if (unlikely(!skb)) + return 0; + + frame->can_id |= CAN_ERR_CRTL; + frame->data[1] = CAN_ERR_CRTL_RX_OVERFLOW; + + if (cdev->is_peripheral) + timestamp = m_can_get_timestamp(cdev); + + m_can_receive_skb(cdev, skb, timestamp); + + return 1; +} + +static int m_can_handle_lec_err(struct net_device *dev, + enum m_can_lec_type lec_type) +{ + struct m_can_classdev *cdev = netdev_priv(dev); + struct net_device_stats *stats = &dev->stats; + struct can_frame *cf; + struct sk_buff *skb; + u32 timestamp = 0; + + cdev->can.can_stats.bus_error++; + stats->rx_errors++; + + /* propagate the error condition to the CAN stack */ + skb = alloc_can_err_skb(dev, &cf); + if (unlikely(!skb)) + return 0; + + /* check for 'last error code' which tells us the + * type of the last error to occur on the CAN bus + */ + cf->can_id |= CAN_ERR_PROT | CAN_ERR_BUSERROR; + + switch (lec_type) { + case LEC_STUFF_ERROR: + netdev_dbg(dev, "stuff error\n"); + cf->data[2] |= CAN_ERR_PROT_STUFF; + break; + case LEC_FORM_ERROR: + netdev_dbg(dev, "form error\n"); + cf->data[2] |= CAN_ERR_PROT_FORM; + break; + case LEC_ACK_ERROR: + netdev_dbg(dev, "ack error\n"); + cf->data[3] = CAN_ERR_PROT_LOC_ACK; + break; + case LEC_BIT1_ERROR: + netdev_dbg(dev, "bit1 error\n"); + cf->data[2] |= CAN_ERR_PROT_BIT1; + break; + case LEC_BIT0_ERROR: + netdev_dbg(dev, "bit0 error\n"); + cf->data[2] |= CAN_ERR_PROT_BIT0; + break; + case LEC_CRC_ERROR: + netdev_dbg(dev, "CRC error\n"); + cf->data[3] = CAN_ERR_PROT_LOC_CRC_SEQ; + break; + default: + break; + } + + if (cdev->is_peripheral) + timestamp = m_can_get_timestamp(cdev); + + m_can_receive_skb(cdev, skb, timestamp); + + return 1; +} + +static int __m_can_get_berr_counter(const struct net_device *dev, + struct can_berr_counter *bec) +{ + struct m_can_classdev *cdev = netdev_priv(dev); + unsigned int ecr; + + ecr = m_can_read(cdev, M_CAN_ECR); + bec->rxerr = FIELD_GET(ECR_REC_MASK, ecr); + bec->txerr = FIELD_GET(ECR_TEC_MASK, ecr); + + return 0; +} + +static int m_can_clk_start(struct m_can_classdev *cdev) +{ + if (cdev->pm_clock_support == 0) + return 0; + + return pm_runtime_resume_and_get(cdev->dev); +} + +static void m_can_clk_stop(struct m_can_classdev *cdev) +{ + if (cdev->pm_clock_support) + pm_runtime_put_sync(cdev->dev); +} + +static int m_can_get_berr_counter(const struct net_device *dev, + struct can_berr_counter *bec) +{ + struct m_can_classdev *cdev = netdev_priv(dev); + int err; + + err = m_can_clk_start(cdev); + if (err) + return err; + + __m_can_get_berr_counter(dev, bec); + + m_can_clk_stop(cdev); + + return 0; +} + +static int m_can_handle_state_change(struct net_device *dev, + enum can_state new_state) +{ + struct m_can_classdev *cdev = netdev_priv(dev); + struct can_frame *cf; + struct sk_buff *skb; + struct can_berr_counter bec; + unsigned int ecr; + u32 timestamp = 0; + + switch (new_state) { + case CAN_STATE_ERROR_WARNING: + /* error warning state */ + cdev->can.can_stats.error_warning++; + cdev->can.state = CAN_STATE_ERROR_WARNING; + break; + case CAN_STATE_ERROR_PASSIVE: + /* error passive state */ + cdev->can.can_stats.error_passive++; + cdev->can.state = CAN_STATE_ERROR_PASSIVE; + break; + case CAN_STATE_BUS_OFF: + /* bus-off state */ + cdev->can.state = CAN_STATE_BUS_OFF; + m_can_disable_all_interrupts(cdev); + cdev->can.can_stats.bus_off++; + can_bus_off(dev); + break; + default: + break; + } + + /* propagate the error condition to the CAN stack */ + skb = alloc_can_err_skb(dev, &cf); + if (unlikely(!skb)) + return 0; + + __m_can_get_berr_counter(dev, &bec); + + switch (new_state) { + case CAN_STATE_ERROR_WARNING: + /* error warning state */ + cf->can_id |= CAN_ERR_CRTL | CAN_ERR_CNT; + cf->data[1] = (bec.txerr > bec.rxerr) ? + CAN_ERR_CRTL_TX_WARNING : + CAN_ERR_CRTL_RX_WARNING; + cf->data[6] = bec.txerr; + cf->data[7] = bec.rxerr; + break; + case CAN_STATE_ERROR_PASSIVE: + /* error passive state */ + cf->can_id |= CAN_ERR_CRTL | CAN_ERR_CNT; + ecr = m_can_read(cdev, M_CAN_ECR); + if (ecr & ECR_RP) + cf->data[1] |= CAN_ERR_CRTL_RX_PASSIVE; + if (bec.txerr > 127) + cf->data[1] |= CAN_ERR_CRTL_TX_PASSIVE; + cf->data[6] = bec.txerr; + cf->data[7] = bec.rxerr; + break; + case CAN_STATE_BUS_OFF: + /* bus-off state */ + cf->can_id |= CAN_ERR_BUSOFF; + break; + default: + break; + } + + if (cdev->is_peripheral) + timestamp = m_can_get_timestamp(cdev); + + m_can_receive_skb(cdev, skb, timestamp); + + return 1; +} + +static int m_can_handle_state_errors(struct net_device *dev, u32 psr) +{ + struct m_can_classdev *cdev = netdev_priv(dev); + int work_done = 0; + + if (psr & PSR_EW && cdev->can.state != CAN_STATE_ERROR_WARNING) { + netdev_dbg(dev, "entered error warning state\n"); + work_done += m_can_handle_state_change(dev, + CAN_STATE_ERROR_WARNING); + } + + if (psr & PSR_EP && cdev->can.state != CAN_STATE_ERROR_PASSIVE) { + netdev_dbg(dev, "entered error passive state\n"); + work_done += m_can_handle_state_change(dev, + CAN_STATE_ERROR_PASSIVE); + } + + if (psr & PSR_BO && cdev->can.state != CAN_STATE_BUS_OFF) { + netdev_dbg(dev, "entered error bus off state\n"); + work_done += m_can_handle_state_change(dev, + CAN_STATE_BUS_OFF); + } + + return work_done; +} + +static void m_can_handle_other_err(struct net_device *dev, u32 irqstatus) +{ + if (irqstatus & IR_WDI) + netdev_err(dev, "Message RAM Watchdog event due to missing READY\n"); + if (irqstatus & IR_BEU) + netdev_err(dev, "Bit Error Uncorrected\n"); + if (irqstatus & IR_BEC) + netdev_err(dev, "Bit Error Corrected\n"); + if (irqstatus & IR_TOO) + netdev_err(dev, "Timeout reached\n"); + if (irqstatus & IR_MRAF) + netdev_err(dev, "Message RAM access failure occurred\n"); +} + +static inline bool is_lec_err(u8 lec) +{ + return lec != LEC_NO_ERROR && lec != LEC_NO_CHANGE; +} + +static inline bool m_can_is_protocol_err(u32 irqstatus) +{ + return irqstatus & IR_ERR_LEC_31X; +} + +static int m_can_handle_protocol_error(struct net_device *dev, u32 irqstatus) +{ + struct net_device_stats *stats = &dev->stats; + struct m_can_classdev *cdev = netdev_priv(dev); + struct can_frame *cf; + struct sk_buff *skb; + u32 timestamp = 0; + + /* propagate the error condition to the CAN stack */ + skb = alloc_can_err_skb(dev, &cf); + + /* update tx error stats since there is protocol error */ + stats->tx_errors++; + + /* update arbitration lost status */ + if (cdev->version >= 31 && (irqstatus & IR_PEA)) { + netdev_dbg(dev, "Protocol error in Arbitration fail\n"); + cdev->can.can_stats.arbitration_lost++; + if (skb) { + cf->can_id |= CAN_ERR_LOSTARB; + cf->data[0] |= CAN_ERR_LOSTARB_UNSPEC; + } + } + + if (unlikely(!skb)) { + netdev_dbg(dev, "allocation of skb failed\n"); + return 0; + } + + if (cdev->is_peripheral) + timestamp = m_can_get_timestamp(cdev); + + m_can_receive_skb(cdev, skb, timestamp); + + return 1; +} + +static int m_can_handle_bus_errors(struct net_device *dev, u32 irqstatus, + u32 psr) +{ + struct m_can_classdev *cdev = netdev_priv(dev); + int work_done = 0; + + if (irqstatus & IR_RF0L) + work_done += m_can_handle_lost_msg(dev); + + /* handle lec errors on the bus */ + if (cdev->can.ctrlmode & CAN_CTRLMODE_BERR_REPORTING) { + u8 lec = FIELD_GET(PSR_LEC_MASK, psr); + u8 dlec = FIELD_GET(PSR_DLEC_MASK, psr); + + if (is_lec_err(lec)) { + netdev_dbg(dev, "Arbitration phase error detected\n"); + work_done += m_can_handle_lec_err(dev, lec); + } + + if (is_lec_err(dlec)) { + netdev_dbg(dev, "Data phase error detected\n"); + work_done += m_can_handle_lec_err(dev, dlec); + } + } + + /* handle protocol errors in arbitration phase */ + if ((cdev->can.ctrlmode & CAN_CTRLMODE_BERR_REPORTING) && + m_can_is_protocol_err(irqstatus)) + work_done += m_can_handle_protocol_error(dev, irqstatus); + + /* other unproccessed error interrupts */ + m_can_handle_other_err(dev, irqstatus); + + return work_done; +} + +static int m_can_rx_handler(struct net_device *dev, int quota, u32 irqstatus) +{ + struct m_can_classdev *cdev = netdev_priv(dev); + int rx_work_or_err; + int work_done = 0; + + if (!irqstatus) + goto end; + + /* Errata workaround for issue "Needless activation of MRAF irq" + * During frame reception while the MCAN is in Error Passive state + * and the Receive Error Counter has the value MCAN_ECR.REC = 127, + * it may happen that MCAN_IR.MRAF is set although there was no + * Message RAM access failure. + * If MCAN_IR.MRAF is enabled, an interrupt to the Host CPU is generated + * The Message RAM Access Failure interrupt routine needs to check + * whether MCAN_ECR.RP = ’1’ and MCAN_ECR.REC = 127. + * In this case, reset MCAN_IR.MRAF. No further action is required. + */ + if (cdev->version <= 31 && irqstatus & IR_MRAF && + m_can_read(cdev, M_CAN_ECR) & ECR_RP) { + struct can_berr_counter bec; + + __m_can_get_berr_counter(dev, &bec); + if (bec.rxerr == 127) { + m_can_write(cdev, M_CAN_IR, IR_MRAF); + irqstatus &= ~IR_MRAF; + } + } + + if (irqstatus & IR_ERR_STATE) + work_done += m_can_handle_state_errors(dev, + m_can_read(cdev, M_CAN_PSR)); + + if (irqstatus & IR_ERR_BUS_30X) + work_done += m_can_handle_bus_errors(dev, irqstatus, + m_can_read(cdev, M_CAN_PSR)); + + if (irqstatus & IR_RF0N) { + rx_work_or_err = m_can_do_rx_poll(dev, (quota - work_done)); + if (rx_work_or_err < 0) + return rx_work_or_err; + + work_done += rx_work_or_err; + } +end: + return work_done; +} + +static int m_can_rx_peripheral(struct net_device *dev, u32 irqstatus) +{ + struct m_can_classdev *cdev = netdev_priv(dev); + int work_done; + + work_done = m_can_rx_handler(dev, NAPI_POLL_WEIGHT, irqstatus); + + /* Don't re-enable interrupts if the driver had a fatal error + * (e.g., FIFO read failure). + */ + if (work_done < 0) + m_can_disable_all_interrupts(cdev); + + return work_done; +} + +static int m_can_poll(struct napi_struct *napi, int quota) +{ + struct net_device *dev = napi->dev; + struct m_can_classdev *cdev = netdev_priv(dev); + int work_done; + u32 irqstatus; + + irqstatus = cdev->irqstatus | m_can_read(cdev, M_CAN_IR); + + work_done = m_can_rx_handler(dev, quota, irqstatus); + + /* Don't re-enable interrupts if the driver had a fatal error + * (e.g., FIFO read failure). + */ + if (work_done >= 0 && work_done < quota) { + napi_complete_done(napi, work_done); + m_can_enable_all_interrupts(cdev); + } + + return work_done; +} + +/* Echo tx skb and update net stats. Peripherals use rx-offload for + * echo. timestamp is used for peripherals to ensure correct ordering + * by rx-offload, and is ignored for non-peripherals. + */ +static void m_can_tx_update_stats(struct m_can_classdev *cdev, + unsigned int msg_mark, + u32 timestamp) +{ + struct net_device *dev = cdev->net; + struct net_device_stats *stats = &dev->stats; + + if (cdev->is_peripheral) + stats->tx_bytes += + can_rx_offload_get_echo_skb_queue_timestamp(&cdev->offload, + msg_mark, + timestamp, + NULL); + else + stats->tx_bytes += can_get_echo_skb(dev, msg_mark, NULL); + + stats->tx_packets++; +} + +static int m_can_echo_tx_event(struct net_device *dev) +{ + u32 txe_count = 0; + u32 m_can_txefs; + u32 fgi = 0; + int ack_fgi = -1; + int i = 0; + int err = 0; + unsigned int msg_mark; + + struct m_can_classdev *cdev = netdev_priv(dev); + + /* read tx event fifo status */ + m_can_txefs = m_can_read(cdev, M_CAN_TXEFS); + + /* Get Tx Event fifo element count */ + txe_count = FIELD_GET(TXEFS_EFFL_MASK, m_can_txefs); + fgi = FIELD_GET(TXEFS_EFGI_MASK, m_can_txefs); + + /* Get and process all sent elements */ + for (i = 0; i < txe_count; i++) { + u32 txe, timestamp = 0; + + /* get message marker, timestamp */ + err = m_can_txe_fifo_read(cdev, fgi, 4, &txe); + if (err) { + netdev_err(dev, "TXE FIFO read returned %d\n", err); + break; + } + + msg_mark = FIELD_GET(TX_EVENT_MM_MASK, txe); + timestamp = FIELD_GET(TX_EVENT_TXTS_MASK, txe) << 16; + + ack_fgi = fgi; + fgi = (++fgi >= cdev->mcfg[MRAM_TXE].num ? 0 : fgi); + + /* update stats */ + m_can_tx_update_stats(cdev, msg_mark, timestamp); + } + + if (ack_fgi != -1) + m_can_write(cdev, M_CAN_TXEFA, FIELD_PREP(TXEFA_EFAI_MASK, + ack_fgi)); + + return err; +} + +static irqreturn_t m_can_isr(int irq, void *dev_id) +{ + struct net_device *dev = (struct net_device *)dev_id; + struct m_can_classdev *cdev = netdev_priv(dev); + u32 ir; + + if (pm_runtime_suspended(cdev->dev)) + return IRQ_NONE; + ir = m_can_read(cdev, M_CAN_IR); + if (!ir) + return IRQ_NONE; + + /* ACK all irqs */ + m_can_write(cdev, M_CAN_IR, ir); + + if (cdev->ops->clear_interrupts) + cdev->ops->clear_interrupts(cdev); + + /* schedule NAPI in case of + * - rx IRQ + * - state change IRQ + * - bus error IRQ and bus error reporting + */ + if ((ir & IR_RF0N) || (ir & IR_ERR_ALL_30X)) { + cdev->irqstatus = ir; + if (!cdev->is_peripheral) { + m_can_disable_all_interrupts(cdev); + napi_schedule(&cdev->napi); + } else if (m_can_rx_peripheral(dev, ir) < 0) { + goto out_fail; + } + } + + if (cdev->version == 30) { + if (ir & IR_TC) { + /* Transmission Complete Interrupt*/ + u32 timestamp = 0; + + if (cdev->is_peripheral) + timestamp = m_can_get_timestamp(cdev); + m_can_tx_update_stats(cdev, 0, timestamp); + netif_wake_queue(dev); + } + } else { + if (ir & IR_TEFN) { + /* New TX FIFO Element arrived */ + if (m_can_echo_tx_event(dev) != 0) + goto out_fail; + + if (netif_queue_stopped(dev) && + !m_can_tx_fifo_full(cdev)) + netif_wake_queue(dev); + } + } + + if (cdev->is_peripheral) + can_rx_offload_threaded_irq_finish(&cdev->offload); + + return IRQ_HANDLED; + +out_fail: + m_can_disable_all_interrupts(cdev); + return IRQ_HANDLED; +} + +static const struct can_bittiming_const m_can_bittiming_const_30X = { + .name = KBUILD_MODNAME, + .tseg1_min = 2, /* Time segment 1 = prop_seg + phase_seg1 */ + .tseg1_max = 64, + .tseg2_min = 1, /* Time segment 2 = phase_seg2 */ + .tseg2_max = 16, + .sjw_max = 16, + .brp_min = 1, + .brp_max = 1024, + .brp_inc = 1, +}; + +static const struct can_bittiming_const m_can_data_bittiming_const_30X = { + .name = KBUILD_MODNAME, + .tseg1_min = 2, /* Time segment 1 = prop_seg + phase_seg1 */ + .tseg1_max = 16, + .tseg2_min = 1, /* Time segment 2 = phase_seg2 */ + .tseg2_max = 8, + .sjw_max = 4, + .brp_min = 1, + .brp_max = 32, + .brp_inc = 1, +}; + +static const struct can_bittiming_const m_can_bittiming_const_31X = { + .name = KBUILD_MODNAME, + .tseg1_min = 2, /* Time segment 1 = prop_seg + phase_seg1 */ + .tseg1_max = 256, + .tseg2_min = 2, /* Time segment 2 = phase_seg2 */ + .tseg2_max = 128, + .sjw_max = 128, + .brp_min = 1, + .brp_max = 512, + .brp_inc = 1, +}; + +static const struct can_bittiming_const m_can_data_bittiming_const_31X = { + .name = KBUILD_MODNAME, + .tseg1_min = 1, /* Time segment 1 = prop_seg + phase_seg1 */ + .tseg1_max = 32, + .tseg2_min = 1, /* Time segment 2 = phase_seg2 */ + .tseg2_max = 16, + .sjw_max = 16, + .brp_min = 1, + .brp_max = 32, + .brp_inc = 1, +}; + +static int m_can_set_bittiming(struct net_device *dev) +{ + struct m_can_classdev *cdev = netdev_priv(dev); + const struct can_bittiming *bt = &cdev->can.bittiming; + const struct can_bittiming *dbt = &cdev->can.data_bittiming; + u16 brp, sjw, tseg1, tseg2; + u32 reg_btp; + + brp = bt->brp - 1; + sjw = bt->sjw - 1; + tseg1 = bt->prop_seg + bt->phase_seg1 - 1; + tseg2 = bt->phase_seg2 - 1; + reg_btp = FIELD_PREP(NBTP_NBRP_MASK, brp) | + FIELD_PREP(NBTP_NSJW_MASK, sjw) | + FIELD_PREP(NBTP_NTSEG1_MASK, tseg1) | + FIELD_PREP(NBTP_NTSEG2_MASK, tseg2); + m_can_write(cdev, M_CAN_NBTP, reg_btp); + + if (cdev->can.ctrlmode & CAN_CTRLMODE_FD) { + reg_btp = 0; + brp = dbt->brp - 1; + sjw = dbt->sjw - 1; + tseg1 = dbt->prop_seg + dbt->phase_seg1 - 1; + tseg2 = dbt->phase_seg2 - 1; + + /* TDC is only needed for bitrates beyond 2.5 MBit/s. + * This is mentioned in the "Bit Time Requirements for CAN FD" + * paper presented at the International CAN Conference 2013 + */ + if (dbt->bitrate > 2500000) { + u32 tdco, ssp; + + /* Use the same value of secondary sampling point + * as the data sampling point + */ + ssp = dbt->sample_point; + + /* Equation based on Bosch's M_CAN User Manual's + * Transmitter Delay Compensation Section + */ + tdco = (cdev->can.clock.freq / 1000) * + ssp / dbt->bitrate; + + /* Max valid TDCO value is 127 */ + if (tdco > 127) { + netdev_warn(dev, "TDCO value of %u is beyond maximum. Using maximum possible value\n", + tdco); + tdco = 127; + } + + reg_btp |= DBTP_TDC; + m_can_write(cdev, M_CAN_TDCR, + FIELD_PREP(TDCR_TDCO_MASK, tdco)); + } + + reg_btp |= FIELD_PREP(DBTP_DBRP_MASK, brp) | + FIELD_PREP(DBTP_DSJW_MASK, sjw) | + FIELD_PREP(DBTP_DTSEG1_MASK, tseg1) | + FIELD_PREP(DBTP_DTSEG2_MASK, tseg2); + + m_can_write(cdev, M_CAN_DBTP, reg_btp); + } + + return 0; +} + +/* Configure M_CAN chip: + * - set rx buffer/fifo element size + * - configure rx fifo + * - accept non-matching frame into fifo 0 + * - configure tx buffer + * - >= v3.1.x: TX FIFO is used + * - configure mode + * - setup bittiming + * - configure timestamp generation + */ +static int m_can_chip_config(struct net_device *dev) +{ + struct m_can_classdev *cdev = netdev_priv(dev); + u32 interrupts = IR_ALL_INT; + u32 cccr, test; + int err; + + err = m_can_init_ram(cdev); + if (err) { + dev_err(cdev->dev, "Message RAM configuration failed\n"); + return err; + } + + /* Disable unused interrupts */ + interrupts &= ~(IR_ARA | IR_ELO | IR_DRX | IR_TEFF | IR_TEFW | IR_TFE | + IR_TCF | IR_HPM | IR_RF1F | IR_RF1W | IR_RF1N | + IR_RF0F | IR_RF0W); + + m_can_config_endisable(cdev, true); + + /* RX Buffer/FIFO Element Size 64 bytes data field */ + m_can_write(cdev, M_CAN_RXESC, + FIELD_PREP(RXESC_RBDS_MASK, RXESC_64B) | + FIELD_PREP(RXESC_F1DS_MASK, RXESC_64B) | + FIELD_PREP(RXESC_F0DS_MASK, RXESC_64B)); + + /* Accept Non-matching Frames Into FIFO 0 */ + m_can_write(cdev, M_CAN_GFC, 0x0); + + if (cdev->version == 30) { + /* only support one Tx Buffer currently */ + m_can_write(cdev, M_CAN_TXBC, FIELD_PREP(TXBC_NDTB_MASK, 1) | + cdev->mcfg[MRAM_TXB].off); + } else { + /* TX FIFO is used for newer IP Core versions */ + m_can_write(cdev, M_CAN_TXBC, + FIELD_PREP(TXBC_TFQS_MASK, + cdev->mcfg[MRAM_TXB].num) | + cdev->mcfg[MRAM_TXB].off); + } + + /* support 64 bytes payload */ + m_can_write(cdev, M_CAN_TXESC, + FIELD_PREP(TXESC_TBDS_MASK, TXESC_TBDS_64B)); + + /* TX Event FIFO */ + if (cdev->version == 30) { + m_can_write(cdev, M_CAN_TXEFC, + FIELD_PREP(TXEFC_EFS_MASK, 1) | + cdev->mcfg[MRAM_TXE].off); + } else { + /* Full TX Event FIFO is used */ + m_can_write(cdev, M_CAN_TXEFC, + FIELD_PREP(TXEFC_EFS_MASK, + cdev->mcfg[MRAM_TXE].num) | + cdev->mcfg[MRAM_TXE].off); + } + + /* rx fifo configuration, blocking mode, fifo size 1 */ + m_can_write(cdev, M_CAN_RXF0C, + FIELD_PREP(RXFC_FS_MASK, cdev->mcfg[MRAM_RXF0].num) | + cdev->mcfg[MRAM_RXF0].off); + + m_can_write(cdev, M_CAN_RXF1C, + FIELD_PREP(RXFC_FS_MASK, cdev->mcfg[MRAM_RXF1].num) | + cdev->mcfg[MRAM_RXF1].off); + + cccr = m_can_read(cdev, M_CAN_CCCR); + test = m_can_read(cdev, M_CAN_TEST); + test &= ~TEST_LBCK; + if (cdev->version == 30) { + /* Version 3.0.x */ + + cccr &= ~(CCCR_TEST | CCCR_MON | CCCR_DAR | + FIELD_PREP(CCCR_CMR_MASK, FIELD_MAX(CCCR_CMR_MASK)) | + FIELD_PREP(CCCR_CME_MASK, FIELD_MAX(CCCR_CME_MASK))); + + if (cdev->can.ctrlmode & CAN_CTRLMODE_FD) + cccr |= FIELD_PREP(CCCR_CME_MASK, CCCR_CME_CANFD_BRS); + + } else { + /* Version 3.1.x or 3.2.x */ + cccr &= ~(CCCR_TEST | CCCR_MON | CCCR_BRSE | CCCR_FDOE | + CCCR_NISO | CCCR_DAR); + + /* Only 3.2.x has NISO Bit implemented */ + if (cdev->can.ctrlmode & CAN_CTRLMODE_FD_NON_ISO) + cccr |= CCCR_NISO; + + if (cdev->can.ctrlmode & CAN_CTRLMODE_FD) + cccr |= (CCCR_BRSE | CCCR_FDOE); + } + + /* Loopback Mode */ + if (cdev->can.ctrlmode & CAN_CTRLMODE_LOOPBACK) { + cccr |= CCCR_TEST | CCCR_MON; + test |= TEST_LBCK; + } + + /* Enable Monitoring (all versions) */ + if (cdev->can.ctrlmode & CAN_CTRLMODE_LISTENONLY) + cccr |= CCCR_MON; + + /* Disable Auto Retransmission (all versions) */ + if (cdev->can.ctrlmode & CAN_CTRLMODE_ONE_SHOT) + cccr |= CCCR_DAR; + + /* Write config */ + m_can_write(cdev, M_CAN_CCCR, cccr); + m_can_write(cdev, M_CAN_TEST, test); + + /* Enable interrupts */ + if (!(cdev->can.ctrlmode & CAN_CTRLMODE_BERR_REPORTING)) { + if (cdev->version == 30) + interrupts &= ~(IR_ERR_LEC_30X); + else + interrupts &= ~(IR_ERR_LEC_31X); + } + m_can_write(cdev, M_CAN_IE, interrupts); + + /* route all interrupts to INT0 */ + m_can_write(cdev, M_CAN_ILS, ILS_ALL_INT0); + + /* set bittiming params */ + m_can_set_bittiming(dev); + + /* enable internal timestamp generation, with a prescaler of 16. The + * prescaler is applied to the nominal bit timing + */ + m_can_write(cdev, M_CAN_TSCC, + FIELD_PREP(TSCC_TCP_MASK, 0xf) | + FIELD_PREP(TSCC_TSS_MASK, TSCC_TSS_INTERNAL)); + + m_can_config_endisable(cdev, false); + + if (cdev->ops->init) + cdev->ops->init(cdev); + + return 0; +} + +static int m_can_start(struct net_device *dev) +{ + struct m_can_classdev *cdev = netdev_priv(dev); + int ret; + + /* basic m_can configuration */ + ret = m_can_chip_config(dev); + if (ret) + return ret; + + cdev->can.state = CAN_STATE_ERROR_ACTIVE; + + m_can_enable_all_interrupts(cdev); + + if (!dev->irq) { + dev_dbg(cdev->dev, "Start hrtimer\n"); + hrtimer_start(&cdev->hrtimer, ms_to_ktime(HRTIMER_POLL_INTERVAL_MS), + HRTIMER_MODE_REL_PINNED); + } + + return 0; +} + +static int m_can_set_mode(struct net_device *dev, enum can_mode mode) +{ + switch (mode) { + case CAN_MODE_START: + m_can_clean(dev); + m_can_start(dev); + netif_wake_queue(dev); + break; + default: + return -EOPNOTSUPP; + } + + return 0; +} + +/* Checks core release number of M_CAN + * returns 0 if an unsupported device is detected + * else it returns the release and step coded as: + * return value = 10 * <release> + 1 * <step> + */ +static int m_can_check_core_release(struct m_can_classdev *cdev) +{ + u32 crel_reg; + u8 rel; + u8 step; + int res; + + /* Read Core Release Version and split into version number + * Example: Version 3.2.1 => rel = 3; step = 2; substep = 1; + */ + crel_reg = m_can_read(cdev, M_CAN_CREL); + rel = (u8)FIELD_GET(CREL_REL_MASK, crel_reg); + step = (u8)FIELD_GET(CREL_STEP_MASK, crel_reg); + + if (rel == 3) { + /* M_CAN v3.x.y: create return value */ + res = 30 + step; + } else { + /* Unsupported M_CAN version */ + res = 0; + } + + return res; +} + +/* Selectable Non ISO support only in version 3.2.x + * This function checks if the bit is writable. + */ +static bool m_can_niso_supported(struct m_can_classdev *cdev) +{ + u32 cccr_reg, cccr_poll = 0; + int niso_timeout = -ETIMEDOUT; + int i; + + m_can_config_endisable(cdev, true); + cccr_reg = m_can_read(cdev, M_CAN_CCCR); + cccr_reg |= CCCR_NISO; + m_can_write(cdev, M_CAN_CCCR, cccr_reg); + + for (i = 0; i <= 10; i++) { + cccr_poll = m_can_read(cdev, M_CAN_CCCR); + if (cccr_poll == cccr_reg) { + niso_timeout = 0; + break; + } + + usleep_range(1, 5); + } + + /* Clear NISO */ + cccr_reg &= ~(CCCR_NISO); + m_can_write(cdev, M_CAN_CCCR, cccr_reg); + + m_can_config_endisable(cdev, false); + + /* return false if time out (-ETIMEDOUT), else return true */ + return !niso_timeout; +} + +static int m_can_dev_setup(struct m_can_classdev *cdev) +{ + struct net_device *dev = cdev->net; + int m_can_version, err; + + m_can_version = m_can_check_core_release(cdev); + /* return if unsupported version */ + if (!m_can_version) { + dev_err(cdev->dev, "Unsupported version number: %2d", + m_can_version); + return -EINVAL; + } + + if (!cdev->is_peripheral) + netif_napi_add(dev, &cdev->napi, m_can_poll); + + /* Shared properties of all M_CAN versions */ + cdev->version = m_can_version; + cdev->can.do_set_mode = m_can_set_mode; + cdev->can.do_get_berr_counter = m_can_get_berr_counter; + + /* Set M_CAN supported operations */ + cdev->can.ctrlmode_supported = CAN_CTRLMODE_LOOPBACK | + CAN_CTRLMODE_LISTENONLY | + CAN_CTRLMODE_BERR_REPORTING | + CAN_CTRLMODE_FD | + CAN_CTRLMODE_ONE_SHOT; + + /* Set properties depending on M_CAN version */ + switch (cdev->version) { + case 30: + /* CAN_CTRLMODE_FD_NON_ISO is fixed with M_CAN IP v3.0.x */ + err = can_set_static_ctrlmode(dev, CAN_CTRLMODE_FD_NON_ISO); + if (err) + return err; + cdev->can.bittiming_const = &m_can_bittiming_const_30X; + cdev->can.data_bittiming_const = &m_can_data_bittiming_const_30X; + break; + case 31: + /* CAN_CTRLMODE_FD_NON_ISO is fixed with M_CAN IP v3.1.x */ + err = can_set_static_ctrlmode(dev, CAN_CTRLMODE_FD_NON_ISO); + if (err) + return err; + cdev->can.bittiming_const = &m_can_bittiming_const_31X; + cdev->can.data_bittiming_const = &m_can_data_bittiming_const_31X; + break; + case 32: + case 33: + /* Support both MCAN version v3.2.x and v3.3.0 */ + cdev->can.bittiming_const = &m_can_bittiming_const_31X; + cdev->can.data_bittiming_const = &m_can_data_bittiming_const_31X; + + cdev->can.ctrlmode_supported |= + (m_can_niso_supported(cdev) ? + CAN_CTRLMODE_FD_NON_ISO : 0); + break; + default: + dev_err(cdev->dev, "Unsupported version number: %2d", + cdev->version); + return -EINVAL; + } + + if (cdev->ops->init) + cdev->ops->init(cdev); + + return 0; +} + +static void m_can_stop(struct net_device *dev) +{ + struct m_can_classdev *cdev = netdev_priv(dev); + + if (!dev->irq) { + dev_dbg(cdev->dev, "Stop hrtimer\n"); + hrtimer_cancel(&cdev->hrtimer); + } + + /* disable all interrupts */ + m_can_disable_all_interrupts(cdev); + + /* Set init mode to disengage from the network */ + m_can_config_endisable(cdev, true); + + /* set the state as STOPPED */ + cdev->can.state = CAN_STATE_STOPPED; +} + +static int m_can_close(struct net_device *dev) +{ + struct m_can_classdev *cdev = netdev_priv(dev); + + netif_stop_queue(dev); + + if (!cdev->is_peripheral) + napi_disable(&cdev->napi); + + m_can_stop(dev); + m_can_clk_stop(cdev); + free_irq(dev->irq, dev); + + if (cdev->is_peripheral) { + cdev->tx_skb = NULL; + destroy_workqueue(cdev->tx_wq); + cdev->tx_wq = NULL; + can_rx_offload_disable(&cdev->offload); + } + + close_candev(dev); + + phy_power_off(cdev->transceiver); + + return 0; +} + +static int m_can_next_echo_skb_occupied(struct net_device *dev, int putidx) +{ + struct m_can_classdev *cdev = netdev_priv(dev); + /*get wrap around for loopback skb index */ + unsigned int wrap = cdev->can.echo_skb_max; + int next_idx; + + /* calculate next index */ + next_idx = (++putidx >= wrap ? 0 : putidx); + + /* check if occupied */ + return !!cdev->can.echo_skb[next_idx]; +} + +static netdev_tx_t m_can_tx_handler(struct m_can_classdev *cdev) +{ + struct canfd_frame *cf = (struct canfd_frame *)cdev->tx_skb->data; + struct net_device *dev = cdev->net; + struct sk_buff *skb = cdev->tx_skb; + struct id_and_dlc fifo_header; + u32 cccr, fdflags; + u32 txfqs; + int err; + int putidx; + + cdev->tx_skb = NULL; + + /* Generate ID field for TX buffer Element */ + /* Common to all supported M_CAN versions */ + if (cf->can_id & CAN_EFF_FLAG) { + fifo_header.id = cf->can_id & CAN_EFF_MASK; + fifo_header.id |= TX_BUF_XTD; + } else { + fifo_header.id = ((cf->can_id & CAN_SFF_MASK) << 18); + } + + if (cf->can_id & CAN_RTR_FLAG) + fifo_header.id |= TX_BUF_RTR; + + if (cdev->version == 30) { + netif_stop_queue(dev); + + fifo_header.dlc = can_fd_len2dlc(cf->len) << 16; + + /* Write the frame ID, DLC, and payload to the FIFO element. */ + err = m_can_fifo_write(cdev, 0, M_CAN_FIFO_ID, &fifo_header, 2); + if (err) + goto out_fail; + + err = m_can_fifo_write(cdev, 0, M_CAN_FIFO_DATA, + cf->data, DIV_ROUND_UP(cf->len, 4)); + if (err) + goto out_fail; + + if (cdev->can.ctrlmode & CAN_CTRLMODE_FD) { + cccr = m_can_read(cdev, M_CAN_CCCR); + cccr &= ~CCCR_CMR_MASK; + if (can_is_canfd_skb(skb)) { + if (cf->flags & CANFD_BRS) + cccr |= FIELD_PREP(CCCR_CMR_MASK, + CCCR_CMR_CANFD_BRS); + else + cccr |= FIELD_PREP(CCCR_CMR_MASK, + CCCR_CMR_CANFD); + } else { + cccr |= FIELD_PREP(CCCR_CMR_MASK, CCCR_CMR_CAN); + } + m_can_write(cdev, M_CAN_CCCR, cccr); + } + m_can_write(cdev, M_CAN_TXBTIE, 0x1); + + can_put_echo_skb(skb, dev, 0, 0); + + m_can_write(cdev, M_CAN_TXBAR, 0x1); + /* End of xmit function for version 3.0.x */ + } else { + /* Transmit routine for version >= v3.1.x */ + + txfqs = m_can_read(cdev, M_CAN_TXFQS); + + /* Check if FIFO full */ + if (_m_can_tx_fifo_full(txfqs)) { + /* This shouldn't happen */ + netif_stop_queue(dev); + netdev_warn(dev, + "TX queue active although FIFO is full."); + + if (cdev->is_peripheral) { + kfree_skb(skb); + dev->stats.tx_dropped++; + return NETDEV_TX_OK; + } else { + return NETDEV_TX_BUSY; + } + } + + /* get put index for frame */ + putidx = FIELD_GET(TXFQS_TFQPI_MASK, txfqs); + + /* Construct DLC Field, with CAN-FD configuration. + * Use the put index of the fifo as the message marker, + * used in the TX interrupt for sending the correct echo frame. + */ + + /* get CAN FD configuration of frame */ + fdflags = 0; + if (can_is_canfd_skb(skb)) { + fdflags |= TX_BUF_FDF; + if (cf->flags & CANFD_BRS) + fdflags |= TX_BUF_BRS; + } + + fifo_header.dlc = FIELD_PREP(TX_BUF_MM_MASK, putidx) | + FIELD_PREP(TX_BUF_DLC_MASK, can_fd_len2dlc(cf->len)) | + fdflags | TX_BUF_EFC; + err = m_can_fifo_write(cdev, putidx, M_CAN_FIFO_ID, &fifo_header, 2); + if (err) + goto out_fail; + + err = m_can_fifo_write(cdev, putidx, M_CAN_FIFO_DATA, + cf->data, DIV_ROUND_UP(cf->len, 4)); + if (err) + goto out_fail; + + /* Push loopback echo. + * Will be looped back on TX interrupt based on message marker + */ + can_put_echo_skb(skb, dev, putidx, 0); + + /* Enable TX FIFO element to start transfer */ + m_can_write(cdev, M_CAN_TXBAR, (1 << putidx)); + + /* stop network queue if fifo full */ + if (m_can_tx_fifo_full(cdev) || + m_can_next_echo_skb_occupied(dev, putidx)) + netif_stop_queue(dev); + } + + return NETDEV_TX_OK; + +out_fail: + netdev_err(dev, "FIFO write returned %d\n", err); + m_can_disable_all_interrupts(cdev); + return NETDEV_TX_BUSY; +} + +static void m_can_tx_work_queue(struct work_struct *ws) +{ + struct m_can_classdev *cdev = container_of(ws, struct m_can_classdev, + tx_work); + + m_can_tx_handler(cdev); +} + +static netdev_tx_t m_can_start_xmit(struct sk_buff *skb, + struct net_device *dev) +{ + struct m_can_classdev *cdev = netdev_priv(dev); + + if (can_dev_dropped_skb(dev, skb)) + return NETDEV_TX_OK; + + if (cdev->is_peripheral) { + if (cdev->tx_skb) { + netdev_err(dev, "hard_xmit called while tx busy\n"); + return NETDEV_TX_BUSY; + } + + if (cdev->can.state == CAN_STATE_BUS_OFF) { + m_can_clean(dev); + } else { + /* Need to stop the queue to avoid numerous requests + * from being sent. Suggested improvement is to create + * a queueing mechanism that will queue the skbs and + * process them in order. + */ + cdev->tx_skb = skb; + netif_stop_queue(cdev->net); + queue_work(cdev->tx_wq, &cdev->tx_work); + } + } else { + cdev->tx_skb = skb; + return m_can_tx_handler(cdev); + } + + return NETDEV_TX_OK; +} + +static enum hrtimer_restart hrtimer_callback(struct hrtimer *timer) +{ + struct m_can_classdev *cdev = container_of(timer, struct + m_can_classdev, hrtimer); + + m_can_isr(0, cdev->net); + + hrtimer_forward_now(timer, ms_to_ktime(HRTIMER_POLL_INTERVAL_MS)); + + return HRTIMER_RESTART; +} + +static int m_can_open(struct net_device *dev) +{ + struct m_can_classdev *cdev = netdev_priv(dev); + int err; + + err = phy_power_on(cdev->transceiver); + if (err) + return err; + + err = m_can_clk_start(cdev); + if (err) + goto out_phy_power_off; + + /* open the can device */ + err = open_candev(dev); + if (err) { + netdev_err(dev, "failed to open can device\n"); + goto exit_disable_clks; + } + + if (cdev->is_peripheral) + can_rx_offload_enable(&cdev->offload); + + /* register interrupt handler */ + if (cdev->is_peripheral) { + cdev->tx_skb = NULL; + cdev->tx_wq = alloc_workqueue("mcan_wq", + WQ_FREEZABLE | WQ_MEM_RECLAIM, 0); + if (!cdev->tx_wq) { + err = -ENOMEM; + goto out_wq_fail; + } + + INIT_WORK(&cdev->tx_work, m_can_tx_work_queue); + + err = request_threaded_irq(dev->irq, NULL, m_can_isr, + IRQF_ONESHOT, + dev->name, dev); + } else if (dev->irq) { + err = request_irq(dev->irq, m_can_isr, IRQF_SHARED, dev->name, + dev); + } + + if (err < 0) { + netdev_err(dev, "failed to request interrupt\n"); + goto exit_irq_fail; + } + + /* start the m_can controller */ + err = m_can_start(dev); + if (err) + goto exit_irq_fail; + + if (!cdev->is_peripheral) + napi_enable(&cdev->napi); + + netif_start_queue(dev); + + return 0; + +exit_irq_fail: + if (cdev->is_peripheral) + destroy_workqueue(cdev->tx_wq); +out_wq_fail: + if (cdev->is_peripheral) + can_rx_offload_disable(&cdev->offload); + close_candev(dev); +exit_disable_clks: + m_can_clk_stop(cdev); +out_phy_power_off: + phy_power_off(cdev->transceiver); + return err; +} + +static const struct net_device_ops m_can_netdev_ops = { + .ndo_open = m_can_open, + .ndo_stop = m_can_close, + .ndo_start_xmit = m_can_start_xmit, + .ndo_change_mtu = can_change_mtu, +}; + +static const struct ethtool_ops m_can_ethtool_ops = { + .get_ts_info = ethtool_op_get_ts_info, +}; + +static int register_m_can_dev(struct net_device *dev) +{ + dev->flags |= IFF_ECHO; /* we support local echo */ + dev->netdev_ops = &m_can_netdev_ops; + dev->ethtool_ops = &m_can_ethtool_ops; + + return register_candev(dev); +} + +int m_can_check_mram_cfg(struct m_can_classdev *cdev, u32 mram_max_size) +{ + u32 total_size; + + total_size = cdev->mcfg[MRAM_TXB].off - cdev->mcfg[MRAM_SIDF].off + + cdev->mcfg[MRAM_TXB].num * TXB_ELEMENT_SIZE; + if (total_size > mram_max_size) { + dev_err(cdev->dev, "Total size of mram config(%u) exceeds mram(%u)\n", + total_size, mram_max_size); + return -EINVAL; + } + + return 0; +} +EXPORT_SYMBOL_GPL(m_can_check_mram_cfg); + +static void m_can_of_parse_mram(struct m_can_classdev *cdev, + const u32 *mram_config_vals) +{ + cdev->mcfg[MRAM_SIDF].off = mram_config_vals[0]; + cdev->mcfg[MRAM_SIDF].num = mram_config_vals[1]; + cdev->mcfg[MRAM_XIDF].off = cdev->mcfg[MRAM_SIDF].off + + cdev->mcfg[MRAM_SIDF].num * SIDF_ELEMENT_SIZE; + cdev->mcfg[MRAM_XIDF].num = mram_config_vals[2]; + cdev->mcfg[MRAM_RXF0].off = cdev->mcfg[MRAM_XIDF].off + + cdev->mcfg[MRAM_XIDF].num * XIDF_ELEMENT_SIZE; + cdev->mcfg[MRAM_RXF0].num = mram_config_vals[3] & + FIELD_MAX(RXFC_FS_MASK); + cdev->mcfg[MRAM_RXF1].off = cdev->mcfg[MRAM_RXF0].off + + cdev->mcfg[MRAM_RXF0].num * RXF0_ELEMENT_SIZE; + cdev->mcfg[MRAM_RXF1].num = mram_config_vals[4] & + FIELD_MAX(RXFC_FS_MASK); + cdev->mcfg[MRAM_RXB].off = cdev->mcfg[MRAM_RXF1].off + + cdev->mcfg[MRAM_RXF1].num * RXF1_ELEMENT_SIZE; + cdev->mcfg[MRAM_RXB].num = mram_config_vals[5]; + cdev->mcfg[MRAM_TXE].off = cdev->mcfg[MRAM_RXB].off + + cdev->mcfg[MRAM_RXB].num * RXB_ELEMENT_SIZE; + cdev->mcfg[MRAM_TXE].num = mram_config_vals[6]; + cdev->mcfg[MRAM_TXB].off = cdev->mcfg[MRAM_TXE].off + + cdev->mcfg[MRAM_TXE].num * TXE_ELEMENT_SIZE; + cdev->mcfg[MRAM_TXB].num = mram_config_vals[7] & + FIELD_MAX(TXBC_NDTB_MASK); + + dev_dbg(cdev->dev, + "sidf 0x%x %d xidf 0x%x %d rxf0 0x%x %d rxf1 0x%x %d rxb 0x%x %d txe 0x%x %d txb 0x%x %d\n", + cdev->mcfg[MRAM_SIDF].off, cdev->mcfg[MRAM_SIDF].num, + cdev->mcfg[MRAM_XIDF].off, cdev->mcfg[MRAM_XIDF].num, + cdev->mcfg[MRAM_RXF0].off, cdev->mcfg[MRAM_RXF0].num, + cdev->mcfg[MRAM_RXF1].off, cdev->mcfg[MRAM_RXF1].num, + cdev->mcfg[MRAM_RXB].off, cdev->mcfg[MRAM_RXB].num, + cdev->mcfg[MRAM_TXE].off, cdev->mcfg[MRAM_TXE].num, + cdev->mcfg[MRAM_TXB].off, cdev->mcfg[MRAM_TXB].num); +} + +int m_can_init_ram(struct m_can_classdev *cdev) +{ + int end, i, start; + int err = 0; + + /* initialize the entire Message RAM in use to avoid possible + * ECC/parity checksum errors when reading an uninitialized buffer + */ + start = cdev->mcfg[MRAM_SIDF].off; + end = cdev->mcfg[MRAM_TXB].off + + cdev->mcfg[MRAM_TXB].num * TXB_ELEMENT_SIZE; + + for (i = start; i < end; i += 4) { + err = m_can_fifo_write_no_off(cdev, i, 0x0); + if (err) + break; + } + + return err; +} +EXPORT_SYMBOL_GPL(m_can_init_ram); + +int m_can_class_get_clocks(struct m_can_classdev *cdev) +{ + int ret = 0; + + cdev->hclk = devm_clk_get(cdev->dev, "hclk"); + cdev->cclk = devm_clk_get(cdev->dev, "cclk"); + + if (IS_ERR(cdev->hclk) || IS_ERR(cdev->cclk)) { + dev_err(cdev->dev, "no clock found\n"); + ret = -ENODEV; + } + + return ret; +} +EXPORT_SYMBOL_GPL(m_can_class_get_clocks); + +struct m_can_classdev *m_can_class_allocate_dev(struct device *dev, + int sizeof_priv) +{ + struct m_can_classdev *class_dev = NULL; + u32 mram_config_vals[MRAM_CFG_LEN]; + struct net_device *net_dev; + u32 tx_fifo_size; + int ret; + + ret = fwnode_property_read_u32_array(dev_fwnode(dev), + "bosch,mram-cfg", + mram_config_vals, + sizeof(mram_config_vals) / 4); + if (ret) { + dev_err(dev, "Could not get Message RAM configuration."); + goto out; + } + + /* Get TX FIFO size + * Defines the total amount of echo buffers for loopback + */ + tx_fifo_size = mram_config_vals[7]; + + /* allocate the m_can device */ + net_dev = alloc_candev(sizeof_priv, tx_fifo_size); + if (!net_dev) { + dev_err(dev, "Failed to allocate CAN device"); + goto out; + } + + class_dev = netdev_priv(net_dev); + class_dev->net = net_dev; + class_dev->dev = dev; + SET_NETDEV_DEV(net_dev, dev); + + m_can_of_parse_mram(class_dev, mram_config_vals); +out: + return class_dev; +} +EXPORT_SYMBOL_GPL(m_can_class_allocate_dev); + +void m_can_class_free_dev(struct net_device *net) +{ + free_candev(net); +} +EXPORT_SYMBOL_GPL(m_can_class_free_dev); + +int m_can_class_register(struct m_can_classdev *cdev) +{ + int ret; + + if (cdev->pm_clock_support) { + ret = m_can_clk_start(cdev); + if (ret) + return ret; + } + + if (cdev->is_peripheral) { + ret = can_rx_offload_add_manual(cdev->net, &cdev->offload, + NAPI_POLL_WEIGHT); + if (ret) + goto clk_disable; + } + + if (!cdev->net->irq) + cdev->hrtimer.function = &hrtimer_callback; + + ret = m_can_dev_setup(cdev); + if (ret) + goto rx_offload_del; + + ret = register_m_can_dev(cdev->net); + if (ret) { + dev_err(cdev->dev, "registering %s failed (err=%d)\n", + cdev->net->name, ret); + goto rx_offload_del; + } + + of_can_transceiver(cdev->net); + + dev_info(cdev->dev, "%s device registered (irq=%d, version=%d)\n", + KBUILD_MODNAME, cdev->net->irq, cdev->version); + + /* Probe finished + * Stop clocks. They will be reactivated once the M_CAN device is opened + */ + m_can_clk_stop(cdev); + + return 0; + +rx_offload_del: + if (cdev->is_peripheral) + can_rx_offload_del(&cdev->offload); +clk_disable: + m_can_clk_stop(cdev); + + return ret; +} +EXPORT_SYMBOL_GPL(m_can_class_register); + +void m_can_class_unregister(struct m_can_classdev *cdev) +{ + if (cdev->is_peripheral) + can_rx_offload_del(&cdev->offload); + unregister_candev(cdev->net); +} +EXPORT_SYMBOL_GPL(m_can_class_unregister); + +int m_can_class_suspend(struct device *dev) +{ + struct m_can_classdev *cdev = dev_get_drvdata(dev); + struct net_device *ndev = cdev->net; + + if (netif_running(ndev)) { + netif_stop_queue(ndev); + netif_device_detach(ndev); + m_can_stop(ndev); + m_can_clk_stop(cdev); + } + + pinctrl_pm_select_sleep_state(dev); + + cdev->can.state = CAN_STATE_SLEEPING; + + return 0; +} +EXPORT_SYMBOL_GPL(m_can_class_suspend); + +int m_can_class_resume(struct device *dev) +{ + struct m_can_classdev *cdev = dev_get_drvdata(dev); + struct net_device *ndev = cdev->net; + + pinctrl_pm_select_default_state(dev); + + cdev->can.state = CAN_STATE_ERROR_ACTIVE; + + if (netif_running(ndev)) { + int ret; + + ret = m_can_clk_start(cdev); + if (ret) + return ret; + ret = m_can_start(ndev); + if (ret) { + m_can_clk_stop(cdev); + + return ret; + } + + netif_device_attach(ndev); + netif_start_queue(ndev); + } + + return 0; +} +EXPORT_SYMBOL_GPL(m_can_class_resume); + +MODULE_AUTHOR("Dong Aisheng <b29396@freescale.com>"); +MODULE_AUTHOR("Dan Murphy <dmurphy@ti.com>"); +MODULE_LICENSE("GPL v2"); +MODULE_DESCRIPTION("CAN bus driver for Bosch M_CAN controller"); |