diff options
Diffstat (limited to 'drivers/net/can/c_can/c_can.c')
| -rw-r--r-- | drivers/net/can/c_can/c_can.c | 1302 |
1 files changed, 0 insertions, 1302 deletions
diff --git a/drivers/net/can/c_can/c_can.c b/drivers/net/can/c_can/c_can.c deleted file mode 100644 index a668cd491cb3..000000000000 --- a/drivers/net/can/c_can/c_can.c +++ /dev/null @@ -1,1302 +0,0 @@ -/* - * CAN bus driver for Bosch C_CAN controller - * - * Copyright (C) 2010 ST Microelectronics - * Bhupesh Sharma <bhupesh.sharma@st.com> - * - * Borrowed heavily from the C_CAN driver originally written by: - * Copyright (C) 2007 - * - Sascha Hauer, Marc Kleine-Budde, Pengutronix <s.hauer@pengutronix.de> - * - Simon Kallweit, intefo AG <simon.kallweit@intefo.ch> - * - * TX and RX NAPI implementation has been borrowed from at91 CAN driver - * written by: - * Copyright - * (C) 2007 by Hans J. Koch <hjk@hansjkoch.de> - * (C) 2008, 2009 by Marc Kleine-Budde <kernel@pengutronix.de> - * - * 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/can.h> -#include <linux/can/dev.h> -#include <linux/can/error.h> -#include <linux/can/led.h> - -#include "c_can.h" - -/* Number of interface registers */ -#define IF_ENUM_REG_LEN 11 -#define C_CAN_IFACE(reg, iface) (C_CAN_IF1_##reg + (iface) * IF_ENUM_REG_LEN) - -/* control extension register D_CAN specific */ -#define CONTROL_EX_PDR BIT(8) - -/* control register */ -#define CONTROL_TEST BIT(7) -#define CONTROL_CCE BIT(6) -#define CONTROL_DISABLE_AR BIT(5) -#define CONTROL_ENABLE_AR (0 << 5) -#define CONTROL_EIE BIT(3) -#define CONTROL_SIE BIT(2) -#define CONTROL_IE BIT(1) -#define CONTROL_INIT BIT(0) - -/* test register */ -#define TEST_RX BIT(7) -#define TEST_TX1 BIT(6) -#define TEST_TX2 BIT(5) -#define TEST_LBACK BIT(4) -#define TEST_SILENT BIT(3) -#define TEST_BASIC BIT(2) - -/* status register */ -#define STATUS_PDA BIT(10) -#define STATUS_BOFF BIT(7) -#define STATUS_EWARN BIT(6) -#define STATUS_EPASS BIT(5) -#define STATUS_RXOK BIT(4) -#define STATUS_TXOK BIT(3) - -/* error counter register */ -#define ERR_CNT_TEC_MASK 0xff -#define ERR_CNT_TEC_SHIFT 0 -#define ERR_CNT_REC_SHIFT 8 -#define ERR_CNT_REC_MASK (0x7f << ERR_CNT_REC_SHIFT) -#define ERR_CNT_RP_SHIFT 15 -#define ERR_CNT_RP_MASK (0x1 << ERR_CNT_RP_SHIFT) - -/* bit-timing register */ -#define BTR_BRP_MASK 0x3f -#define BTR_BRP_SHIFT 0 -#define BTR_SJW_SHIFT 6 -#define BTR_SJW_MASK (0x3 << BTR_SJW_SHIFT) -#define BTR_TSEG1_SHIFT 8 -#define BTR_TSEG1_MASK (0xf << BTR_TSEG1_SHIFT) -#define BTR_TSEG2_SHIFT 12 -#define BTR_TSEG2_MASK (0x7 << BTR_TSEG2_SHIFT) - -/* brp extension register */ -#define BRP_EXT_BRPE_MASK 0x0f -#define BRP_EXT_BRPE_SHIFT 0 - -/* IFx command request */ -#define IF_COMR_BUSY BIT(15) - -/* IFx command mask */ -#define IF_COMM_WR BIT(7) -#define IF_COMM_MASK BIT(6) -#define IF_COMM_ARB BIT(5) -#define IF_COMM_CONTROL BIT(4) -#define IF_COMM_CLR_INT_PND BIT(3) -#define IF_COMM_TXRQST BIT(2) -#define IF_COMM_DATAA BIT(1) -#define IF_COMM_DATAB BIT(0) -#define IF_COMM_ALL (IF_COMM_MASK | IF_COMM_ARB | \ - IF_COMM_CONTROL | IF_COMM_TXRQST | \ - IF_COMM_DATAA | IF_COMM_DATAB) - -/* IFx arbitration */ -#define IF_ARB_MSGVAL BIT(15) -#define IF_ARB_MSGXTD BIT(14) -#define IF_ARB_TRANSMIT BIT(13) - -/* IFx message control */ -#define IF_MCONT_NEWDAT BIT(15) -#define IF_MCONT_MSGLST BIT(14) -#define IF_MCONT_CLR_MSGLST (0 << 14) -#define IF_MCONT_INTPND BIT(13) -#define IF_MCONT_UMASK BIT(12) -#define IF_MCONT_TXIE BIT(11) -#define IF_MCONT_RXIE BIT(10) -#define IF_MCONT_RMTEN BIT(9) -#define IF_MCONT_TXRQST BIT(8) -#define IF_MCONT_EOB BIT(7) -#define IF_MCONT_DLC_MASK 0xf - -/* - * IFx register masks: - * allow easy operation on 16-bit registers when the - * argument is 32-bit instead - */ -#define IFX_WRITE_LOW_16BIT(x) ((x) & 0xFFFF) -#define IFX_WRITE_HIGH_16BIT(x) (((x) & 0xFFFF0000) >> 16) - -/* message object split */ -#define C_CAN_NO_OF_OBJECTS 32 -#define C_CAN_MSG_OBJ_RX_NUM 16 -#define C_CAN_MSG_OBJ_TX_NUM 16 - -#define C_CAN_MSG_OBJ_RX_FIRST 1 -#define C_CAN_MSG_OBJ_RX_LAST (C_CAN_MSG_OBJ_RX_FIRST + \ - C_CAN_MSG_OBJ_RX_NUM - 1) - -#define C_CAN_MSG_OBJ_TX_FIRST (C_CAN_MSG_OBJ_RX_LAST + 1) -#define C_CAN_MSG_OBJ_TX_LAST (C_CAN_MSG_OBJ_TX_FIRST + \ - C_CAN_MSG_OBJ_TX_NUM - 1) - -#define C_CAN_MSG_OBJ_RX_SPLIT 9 -#define C_CAN_MSG_RX_LOW_LAST (C_CAN_MSG_OBJ_RX_SPLIT - 1) - -#define C_CAN_NEXT_MSG_OBJ_MASK (C_CAN_MSG_OBJ_TX_NUM - 1) -#define RECEIVE_OBJECT_BITS 0x0000ffff - -/* status interrupt */ -#define STATUS_INTERRUPT 0x8000 - -/* global interrupt masks */ -#define ENABLE_ALL_INTERRUPTS 1 -#define DISABLE_ALL_INTERRUPTS 0 - -/* minimum timeout for checking BUSY status */ -#define MIN_TIMEOUT_VALUE 6 - -/* Wait for ~1 sec for INIT bit */ -#define INIT_WAIT_MS 1000 - -/* napi related */ -#define C_CAN_NAPI_WEIGHT C_CAN_MSG_OBJ_RX_NUM - -/* c_can lec values */ -enum c_can_lec_type { - LEC_NO_ERROR = 0, - LEC_STUFF_ERROR, - LEC_FORM_ERROR, - LEC_ACK_ERROR, - LEC_BIT1_ERROR, - LEC_BIT0_ERROR, - LEC_CRC_ERROR, - LEC_UNUSED, -}; - -/* - * c_can error types: - * Bus errors (BUS_OFF, ERROR_WARNING, ERROR_PASSIVE) are supported - */ -enum c_can_bus_error_types { - C_CAN_NO_ERROR = 0, - C_CAN_BUS_OFF, - C_CAN_ERROR_WARNING, - C_CAN_ERROR_PASSIVE, -}; - -static const struct can_bittiming_const c_can_bittiming_const = { - .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 = 1024, /* 6-bit BRP field + 4-bit BRPE field*/ - .brp_inc = 1, -}; - -static inline void c_can_pm_runtime_enable(const struct c_can_priv *priv) -{ - if (priv->device) - pm_runtime_enable(priv->device); -} - -static inline void c_can_pm_runtime_disable(const struct c_can_priv *priv) -{ - if (priv->device) - pm_runtime_disable(priv->device); -} - -static inline void c_can_pm_runtime_get_sync(const struct c_can_priv *priv) -{ - if (priv->device) - pm_runtime_get_sync(priv->device); -} - -static inline void c_can_pm_runtime_put_sync(const struct c_can_priv *priv) -{ - if (priv->device) - pm_runtime_put_sync(priv->device); -} - -static inline void c_can_reset_ram(const struct c_can_priv *priv, bool enable) -{ - if (priv->raminit) - priv->raminit(priv, enable); -} - -static inline int get_tx_next_msg_obj(const struct c_can_priv *priv) -{ - return (priv->tx_next & C_CAN_NEXT_MSG_OBJ_MASK) + - C_CAN_MSG_OBJ_TX_FIRST; -} - -static inline int get_tx_echo_msg_obj(const struct c_can_priv *priv) -{ - return (priv->tx_echo & C_CAN_NEXT_MSG_OBJ_MASK) + - C_CAN_MSG_OBJ_TX_FIRST; -} - -static u32 c_can_read_reg32(struct c_can_priv *priv, enum reg index) -{ - u32 val = priv->read_reg(priv, index); - val |= ((u32) priv->read_reg(priv, index + 1)) << 16; - return val; -} - -static void c_can_enable_all_interrupts(struct c_can_priv *priv, - int enable) -{ - unsigned int cntrl_save = priv->read_reg(priv, - C_CAN_CTRL_REG); - - if (enable) - cntrl_save |= (CONTROL_SIE | CONTROL_EIE | CONTROL_IE); - else - cntrl_save &= ~(CONTROL_EIE | CONTROL_IE | CONTROL_SIE); - - priv->write_reg(priv, C_CAN_CTRL_REG, cntrl_save); -} - -static inline int c_can_msg_obj_is_busy(struct c_can_priv *priv, int iface) -{ - int count = MIN_TIMEOUT_VALUE; - - while (count && priv->read_reg(priv, - C_CAN_IFACE(COMREQ_REG, iface)) & - IF_COMR_BUSY) { - count--; - udelay(1); - } - - if (!count) - return 1; - - return 0; -} - -static inline void c_can_object_get(struct net_device *dev, - int iface, int objno, int mask) -{ - struct c_can_priv *priv = netdev_priv(dev); - - /* - * As per specs, after writting the message object number in the - * IF command request register the transfer b/w interface - * register and message RAM must be complete in 6 CAN-CLK - * period. - */ - priv->write_reg(priv, C_CAN_IFACE(COMMSK_REG, iface), - IFX_WRITE_LOW_16BIT(mask)); - priv->write_reg(priv, C_CAN_IFACE(COMREQ_REG, iface), - IFX_WRITE_LOW_16BIT(objno)); - - if (c_can_msg_obj_is_busy(priv, iface)) - netdev_err(dev, "timed out in object get\n"); -} - -static inline void c_can_object_put(struct net_device *dev, - int iface, int objno, int mask) -{ - struct c_can_priv *priv = netdev_priv(dev); - - /* - * As per specs, after writting the message object number in the - * IF command request register the transfer b/w interface - * register and message RAM must be complete in 6 CAN-CLK - * period. - */ - priv->write_reg(priv, C_CAN_IFACE(COMMSK_REG, iface), - (IF_COMM_WR | IFX_WRITE_LOW_16BIT(mask))); - priv->write_reg(priv, C_CAN_IFACE(COMREQ_REG, iface), - IFX_WRITE_LOW_16BIT(objno)); - - if (c_can_msg_obj_is_busy(priv, iface)) - netdev_err(dev, "timed out in object put\n"); -} - -static void c_can_write_msg_object(struct net_device *dev, - int iface, struct can_frame *frame, int objno) -{ - int i; - u16 flags = 0; - unsigned int id; - struct c_can_priv *priv = netdev_priv(dev); - - if (!(frame->can_id & CAN_RTR_FLAG)) - flags |= IF_ARB_TRANSMIT; - - if (frame->can_id & CAN_EFF_FLAG) { - id = frame->can_id & CAN_EFF_MASK; - flags |= IF_ARB_MSGXTD; - } else - id = ((frame->can_id & CAN_SFF_MASK) << 18); - - flags |= IF_ARB_MSGVAL; - - priv->write_reg(priv, C_CAN_IFACE(ARB1_REG, iface), - IFX_WRITE_LOW_16BIT(id)); - priv->write_reg(priv, C_CAN_IFACE(ARB2_REG, iface), flags | - IFX_WRITE_HIGH_16BIT(id)); - - for (i = 0; i < frame->can_dlc; i += 2) { - priv->write_reg(priv, C_CAN_IFACE(DATA1_REG, iface) + i / 2, - frame->data[i] | (frame->data[i + 1] << 8)); - } - - /* enable interrupt for this message object */ - priv->write_reg(priv, C_CAN_IFACE(MSGCTRL_REG, iface), - IF_MCONT_TXIE | IF_MCONT_TXRQST | IF_MCONT_EOB | - frame->can_dlc); - c_can_object_put(dev, iface, objno, IF_COMM_ALL); -} - -static inline void c_can_mark_rx_msg_obj(struct net_device *dev, - int iface, int ctrl_mask, - int obj) -{ - struct c_can_priv *priv = netdev_priv(dev); - - priv->write_reg(priv, C_CAN_IFACE(MSGCTRL_REG, iface), - ctrl_mask & ~(IF_MCONT_MSGLST | IF_MCONT_INTPND)); - c_can_object_put(dev, iface, obj, IF_COMM_CONTROL); - -} - -static inline void c_can_activate_all_lower_rx_msg_obj(struct net_device *dev, - int iface, - int ctrl_mask) -{ - int i; - struct c_can_priv *priv = netdev_priv(dev); - - for (i = C_CAN_MSG_OBJ_RX_FIRST; i <= C_CAN_MSG_RX_LOW_LAST; i++) { - priv->write_reg(priv, C_CAN_IFACE(MSGCTRL_REG, iface), - ctrl_mask & ~(IF_MCONT_MSGLST | - IF_MCONT_INTPND | IF_MCONT_NEWDAT)); - c_can_object_put(dev, iface, i, IF_COMM_CONTROL); - } -} - -static inline void c_can_activate_rx_msg_obj(struct net_device *dev, - int iface, int ctrl_mask, - int obj) -{ - struct c_can_priv *priv = netdev_priv(dev); - - priv->write_reg(priv, C_CAN_IFACE(MSGCTRL_REG, iface), - ctrl_mask & ~(IF_MCONT_MSGLST | - IF_MCONT_INTPND | IF_MCONT_NEWDAT)); - c_can_object_put(dev, iface, obj, IF_COMM_CONTROL); -} - -static void c_can_handle_lost_msg_obj(struct net_device *dev, - int iface, int objno) -{ - struct c_can_priv *priv = netdev_priv(dev); - struct net_device_stats *stats = &dev->stats; - struct sk_buff *skb; - struct can_frame *frame; - - netdev_err(dev, "msg lost in buffer %d\n", objno); - - c_can_object_get(dev, iface, objno, IF_COMM_ALL & ~IF_COMM_TXRQST); - - priv->write_reg(priv, C_CAN_IFACE(MSGCTRL_REG, iface), - IF_MCONT_CLR_MSGLST); - - c_can_object_put(dev, 0, objno, IF_COMM_CONTROL); - - /* create an error msg */ - skb = alloc_can_err_skb(dev, &frame); - if (unlikely(!skb)) - return; - - frame->can_id |= CAN_ERR_CRTL; - frame->data[1] = CAN_ERR_CRTL_RX_OVERFLOW; - stats->rx_errors++; - stats->rx_over_errors++; - - netif_receive_skb(skb); -} - -static int c_can_read_msg_object(struct net_device *dev, int iface, int ctrl) -{ - u16 flags, data; - int i; - unsigned int val; - struct c_can_priv *priv = netdev_priv(dev); - struct net_device_stats *stats = &dev->stats; - struct sk_buff *skb; - struct can_frame *frame; - - skb = alloc_can_skb(dev, &frame); - if (!skb) { - stats->rx_dropped++; - return -ENOMEM; - } - - frame->can_dlc = get_can_dlc(ctrl & 0x0F); - - flags = priv->read_reg(priv, C_CAN_IFACE(ARB2_REG, iface)); - val = priv->read_reg(priv, C_CAN_IFACE(ARB1_REG, iface)) | - (flags << 16); - - if (flags & IF_ARB_MSGXTD) - frame->can_id = (val & CAN_EFF_MASK) | CAN_EFF_FLAG; - else - frame->can_id = (val >> 18) & CAN_SFF_MASK; - - if (flags & IF_ARB_TRANSMIT) - frame->can_id |= CAN_RTR_FLAG; - else { - for (i = 0; i < frame->can_dlc; i += 2) { - data = priv->read_reg(priv, - C_CAN_IFACE(DATA1_REG, iface) + i / 2); - frame->data[i] = data; - frame->data[i + 1] = data >> 8; - } - } - - netif_receive_skb(skb); - - stats->rx_packets++; - stats->rx_bytes += frame->can_dlc; - - can_led_event(dev, CAN_LED_EVENT_RX); - - return 0; -} - -static void c_can_setup_receive_object(struct net_device *dev, int iface, - int objno, unsigned int mask, - unsigned int id, unsigned int mcont) -{ - struct c_can_priv *priv = netdev_priv(dev); - - priv->write_reg(priv, C_CAN_IFACE(MASK1_REG, iface), - IFX_WRITE_LOW_16BIT(mask)); - - /* According to C_CAN documentation, the reserved bit - * in IFx_MASK2 register is fixed 1 - */ - priv->write_reg(priv, C_CAN_IFACE(MASK2_REG, iface), - IFX_WRITE_HIGH_16BIT(mask) | BIT(13)); - - priv->write_reg(priv, C_CAN_IFACE(ARB1_REG, iface), - IFX_WRITE_LOW_16BIT(id)); - priv->write_reg(priv, C_CAN_IFACE(ARB2_REG, iface), - (IF_ARB_MSGVAL | IFX_WRITE_HIGH_16BIT(id))); - - priv->write_reg(priv, C_CAN_IFACE(MSGCTRL_REG, iface), mcont); - c_can_object_put(dev, iface, objno, IF_COMM_ALL & ~IF_COMM_TXRQST); - - netdev_dbg(dev, "obj no:%d, msgval:0x%08x\n", objno, - c_can_read_reg32(priv, C_CAN_MSGVAL1_REG)); -} - -static void c_can_inval_msg_object(struct net_device *dev, int iface, int objno) -{ - struct c_can_priv *priv = netdev_priv(dev); - - priv->write_reg(priv, C_CAN_IFACE(ARB1_REG, iface), 0); - priv->write_reg(priv, C_CAN_IFACE(ARB2_REG, iface), 0); - priv->write_reg(priv, C_CAN_IFACE(MSGCTRL_REG, iface), 0); - - c_can_object_put(dev, iface, objno, IF_COMM_ARB | IF_COMM_CONTROL); - - netdev_dbg(dev, "obj no:%d, msgval:0x%08x\n", objno, - c_can_read_reg32(priv, C_CAN_MSGVAL1_REG)); -} - -static inline int c_can_is_next_tx_obj_busy(struct c_can_priv *priv, int objno) -{ - int val = c_can_read_reg32(priv, C_CAN_TXRQST1_REG); - - /* - * as transmission request register's bit n-1 corresponds to - * message object n, we need to handle the same properly. - */ - if (val & (1 << (objno - 1))) - return 1; - - return 0; -} - -static netdev_tx_t c_can_start_xmit(struct sk_buff *skb, - struct net_device *dev) -{ - u32 msg_obj_no; - struct c_can_priv *priv = netdev_priv(dev); - struct can_frame *frame = (struct can_frame *)skb->data; - - if (can_dropped_invalid_skb(dev, skb)) - return NETDEV_TX_OK; - - msg_obj_no = get_tx_next_msg_obj(priv); - - /* prepare message object for transmission */ - c_can_write_msg_object(dev, 0, frame, msg_obj_no); - can_put_echo_skb(skb, dev, msg_obj_no - C_CAN_MSG_OBJ_TX_FIRST); - - /* - * we have to stop the queue in case of a wrap around or - * if the next TX message object is still in use - */ - priv->tx_next++; - if (c_can_is_next_tx_obj_busy(priv, get_tx_next_msg_obj(priv)) || - (priv->tx_next & C_CAN_NEXT_MSG_OBJ_MASK) == 0) - netif_stop_queue(dev); - - return NETDEV_TX_OK; -} - -static int c_can_set_bittiming(struct net_device *dev) -{ - unsigned int reg_btr, reg_brpe, ctrl_save; - u8 brp, brpe, sjw, tseg1, tseg2; - u32 ten_bit_brp; - struct c_can_priv *priv = netdev_priv(dev); - const struct can_bittiming *bt = &priv->can.bittiming; - - /* c_can provides a 6-bit brp and 4-bit brpe fields */ - ten_bit_brp = bt->brp - 1; - brp = ten_bit_brp & BTR_BRP_MASK; - brpe = ten_bit_brp >> 6; - - sjw = bt->sjw - 1; - tseg1 = bt->prop_seg + bt->phase_seg1 - 1; - tseg2 = bt->phase_seg2 - 1; - reg_btr = brp | (sjw << BTR_SJW_SHIFT) | (tseg1 << BTR_TSEG1_SHIFT) | - (tseg2 << BTR_TSEG2_SHIFT); - reg_brpe = brpe & BRP_EXT_BRPE_MASK; - - netdev_info(dev, - "setting BTR=%04x BRPE=%04x\n", reg_btr, reg_brpe); - - ctrl_save = priv->read_reg(priv, C_CAN_CTRL_REG); - priv->write_reg(priv, C_CAN_CTRL_REG, - ctrl_save | CONTROL_CCE | CONTROL_INIT); - priv->write_reg(priv, C_CAN_BTR_REG, reg_btr); - priv->write_reg(priv, C_CAN_BRPEXT_REG, reg_brpe); - priv->write_reg(priv, C_CAN_CTRL_REG, ctrl_save); - - return 0; -} - -/* - * 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) -{ - int i; - - /* first invalidate all message objects */ - for (i = C_CAN_MSG_OBJ_RX_FIRST; i <= C_CAN_NO_OF_OBJECTS; i++) - c_can_inval_msg_object(dev, 0, i); - - /* setup receive message objects */ - for (i = C_CAN_MSG_OBJ_RX_FIRST; i < C_CAN_MSG_OBJ_RX_LAST; i++) - c_can_setup_receive_object(dev, 0, i, 0, 0, - (IF_MCONT_RXIE | IF_MCONT_UMASK) & ~IF_MCONT_EOB); - - c_can_setup_receive_object(dev, 0, C_CAN_MSG_OBJ_RX_LAST, 0, 0, - IF_MCONT_EOB | IF_MCONT_RXIE | IF_MCONT_UMASK); -} - -/* - * Configure C_CAN chip: - * - enable/disable auto-retransmission - * - set operating mode - * - configure message objects - */ -static void c_can_chip_config(struct net_device *dev) -{ - struct c_can_priv *priv = netdev_priv(dev); - - /* enable automatic retransmission */ - priv->write_reg(priv, C_CAN_CTRL_REG, - CONTROL_ENABLE_AR); - - if ((priv->can.ctrlmode & CAN_CTRLMODE_LISTENONLY) && - (priv->can.ctrlmode & CAN_CTRLMODE_LOOPBACK)) { - /* loopback + silent mode : useful for hot self-test */ - priv->write_reg(priv, C_CAN_CTRL_REG, CONTROL_EIE | - CONTROL_SIE | CONTROL_IE | CONTROL_TEST); - priv->write_reg(priv, C_CAN_TEST_REG, - TEST_LBACK | TEST_SILENT); - } else if (priv->can.ctrlmode & CAN_CTRLMODE_LOOPBACK) { - /* loopback mode : useful for self-test function */ - priv->write_reg(priv, C_CAN_CTRL_REG, CONTROL_EIE | - CONTROL_SIE | CONTROL_IE | CONTROL_TEST); - priv->write_reg(priv, C_CAN_TEST_REG, TEST_LBACK); - } else if (priv->can.ctrlmode & CAN_CTRLMODE_LISTENONLY) { - /* silent mode : bus-monitoring mode */ - priv->write_reg(priv, C_CAN_CTRL_REG, CONTROL_EIE | - CONTROL_SIE | CONTROL_IE | CONTROL_TEST); - priv->write_reg(priv, C_CAN_TEST_REG, TEST_SILENT); - } else - /* normal mode*/ - priv->write_reg(priv, C_CAN_CTRL_REG, - CONTROL_EIE | CONTROL_SIE | CONTROL_IE); - - /* configure message objects */ - c_can_configure_msg_objects(dev); - - /* set a `lec` value so that we can check for updates later */ - priv->write_reg(priv, C_CAN_STS_REG, LEC_UNUSED); - - /* set bittiming params */ - c_can_set_bittiming(dev); -} - -static void c_can_start(struct net_device *dev) -{ - struct c_can_priv *priv = netdev_priv(dev); - - /* basic c_can configuration */ - c_can_chip_config(dev); - - priv->can.state = CAN_STATE_ERROR_ACTIVE; - - /* reset tx helper pointers */ - priv->tx_next = priv->tx_echo = 0; - - /* enable status change, error and module interrupts */ - c_can_enable_all_interrupts(priv, ENABLE_ALL_INTERRUPTS); -} - -static void c_can_stop(struct net_device *dev) -{ - struct c_can_priv *priv = netdev_priv(dev); - - /* disable all interrupts */ - c_can_enable_all_interrupts(priv, DISABLE_ALL_INTERRUPTS); - - /* set the state as STOPPED */ - priv->can.state = CAN_STATE_STOPPED; -} - -static int c_can_set_mode(struct net_device *dev, enum can_mode mode) -{ - switch (mode) { - case CAN_MODE_START: - c_can_start(dev); - netif_wake_queue(dev); - break; - default: - return -EOPNOTSUPP; - } - - return 0; -} - -static int c_can_get_berr_counter(const struct net_device *dev, - struct can_berr_counter *bec) -{ - unsigned int reg_err_counter; - struct c_can_priv *priv = netdev_priv(dev); - - c_can_pm_runtime_get_sync(priv); - - reg_err_counter = priv->read_reg(priv, C_CAN_ERR_CNT_REG); - bec->rxerr = (reg_err_counter & ERR_CNT_REC_MASK) >> - ERR_CNT_REC_SHIFT; - bec->txerr = reg_err_counter & ERR_CNT_TEC_MASK; - - c_can_pm_runtime_put_sync(priv); - - return 0; -} - -/* - * theory of operation: - * - * priv->tx_echo holds the number of the oldest can_frame put for - * transmission into the hardware, but not yet ACKed by the CAN tx - * complete IRQ. - * - * We iterate from priv->tx_echo to priv->tx_next and check if the - * packet has been transmitted, echo it back to the CAN framework. - * If we discover a not yet transmitted packet, stop looking for more. - */ -static void c_can_do_tx(struct net_device *dev) -{ - u32 val; - u32 msg_obj_no; - struct c_can_priv *priv = netdev_priv(dev); - struct net_device_stats *stats = &dev->stats; - - for (/* nix */; (priv->tx_next - priv->tx_echo) > 0; priv->tx_echo++) { - msg_obj_no = get_tx_echo_msg_obj(priv); - val = c_can_read_reg32(priv, C_CAN_TXRQST1_REG); - if (!(val & (1 << (msg_obj_no - 1)))) { - can_get_echo_skb(dev, - msg_obj_no - C_CAN_MSG_OBJ_TX_FIRST); - stats->tx_bytes += priv->read_reg(priv, - C_CAN_IFACE(MSGCTRL_REG, 0)) - & IF_MCONT_DLC_MASK; - stats->tx_packets++; - can_led_event(dev, CAN_LED_EVENT_TX); - c_can_inval_msg_object(dev, 0, msg_obj_no); - } else { - break; - } - } - - /* restart queue if wrap-up or if queue stalled on last pkt */ - if (((priv->tx_next & C_CAN_NEXT_MSG_OBJ_MASK) != 0) || - ((priv->tx_echo & C_CAN_NEXT_MSG_OBJ_MASK) == 0)) - netif_wake_queue(dev); -} - -/* - * 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. To work-around this issue, we keep two groups of message - * objects whose partitioning is defined by C_CAN_MSG_OBJ_RX_SPLIT. - * - * To ensure in-order frame reception we use the following - * approach while re-activating a message object to receive further - * frames: - * - if the current message object number is lower than - * C_CAN_MSG_RX_LOW_LAST, do not clear the NEWDAT bit while clearing - * the INTPND bit. - * - if the current message object number is equal to - * C_CAN_MSG_RX_LOW_LAST then clear the NEWDAT bit of all lower - * receive message objects. - * - if the current message object number is greater than - * C_CAN_MSG_RX_LOW_LAST then clear the NEWDAT bit of - * only this message object. - */ -static int c_can_do_rx_poll(struct net_device *dev, int quota) -{ - u32 num_rx_pkts = 0; - unsigned int msg_obj, msg_ctrl_save; - struct c_can_priv *priv = netdev_priv(dev); - u32 val = c_can_read_reg32(priv, C_CAN_INTPND1_REG); - - for (msg_obj = C_CAN_MSG_OBJ_RX_FIRST; - msg_obj <= C_CAN_MSG_OBJ_RX_LAST && quota > 0; - val = c_can_read_reg32(priv, C_CAN_INTPND1_REG), - msg_obj++) { - /* - * as interrupt pending register's bit n-1 corresponds to - * message object n, we need to handle the same properly. - */ - if (val & (1 << (msg_obj - 1))) { - c_can_object_get(dev, 0, msg_obj, IF_COMM_ALL & - ~IF_COMM_TXRQST); - msg_ctrl_save = priv->read_reg(priv, - C_CAN_IFACE(MSGCTRL_REG, 0)); - - if (msg_ctrl_save & IF_MCONT_EOB) - return num_rx_pkts; - - if (msg_ctrl_save & IF_MCONT_MSGLST) { - c_can_handle_lost_msg_obj(dev, 0, msg_obj); - num_rx_pkts++; - quota--; - continue; - } - - if (!(msg_ctrl_save & IF_MCONT_NEWDAT)) - continue; - - /* read the data from the message object */ - c_can_read_msg_object(dev, 0, msg_ctrl_save); - - if (msg_obj < C_CAN_MSG_RX_LOW_LAST) - c_can_mark_rx_msg_obj(dev, 0, - msg_ctrl_save, msg_obj); - else if (msg_obj > C_CAN_MSG_RX_LOW_LAST) - /* activate this msg obj */ - c_can_activate_rx_msg_obj(dev, 0, - msg_ctrl_save, msg_obj); - else if (msg_obj == C_CAN_MSG_RX_LOW_LAST) - /* activate all lower message objects */ - c_can_activate_all_lower_rx_msg_obj(dev, - 0, msg_ctrl_save); - - num_rx_pkts++; - quota--; - } - } - - return num_rx_pkts; -} - -static inline int c_can_has_and_handle_berr(struct c_can_priv *priv) -{ - return (priv->can.ctrlmode & CAN_CTRLMODE_BERR_REPORTING) && - (priv->current_status & LEC_UNUSED); -} - -static int c_can_handle_state_change(struct net_device *dev, - enum c_can_bus_error_types error_type) -{ - unsigned int reg_err_counter; - unsigned int rx_err_passive; - struct c_can_priv *priv = netdev_priv(dev); - struct net_device_stats *stats = &dev->stats; - struct can_frame *cf; - struct sk_buff *skb; - struct can_berr_counter bec; - - /* propagate the error condition to the CAN stack */ - skb = alloc_can_err_skb(dev, &cf); - if (unlikely(!skb)) - return 0; - - c_can_get_berr_counter(dev, &bec); - reg_err_counter = priv->read_reg(priv, C_CAN_ERR_CNT_REG); - rx_err_passive = (reg_err_counter & ERR_CNT_RP_MASK) >> - ERR_CNT_RP_SHIFT; - - switch (error_type) { - case C_CAN_ERROR_WARNING: - /* error warning state */ - priv->can.can_stats.error_warning++; - priv->can.state = CAN_STATE_ERROR_WARNING; - cf->can_id |= CAN_ERR_CRTL; - 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 C_CAN_ERROR_PASSIVE: - /* error passive state */ - priv->can.can_stats.error_passive++; - priv->can.state = CAN_STATE_ERROR_PASSIVE; - cf->can_id |= CAN_ERR_CRTL; - if (rx_err_passive) - 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 C_CAN_BUS_OFF: - /* bus-off state */ - priv->can.state = CAN_STATE_BUS_OFF; - cf->can_id |= CAN_ERR_BUSOFF; - /* - * disable all interrupts in bus-off mode to ensure that - * the CPU is not hogged down - */ - c_can_enable_all_interrupts(priv, DISABLE_ALL_INTERRUPTS); - can_bus_off(dev); - break; - default: - break; - } - - netif_receive_skb(skb); - stats->rx_packets++; - stats->rx_bytes += cf->can_dlc; - - return 1; -} - -static int c_can_handle_bus_err(struct net_device *dev, - enum c_can_lec_type lec_type) -{ - struct c_can_priv *priv = netdev_priv(dev); - struct net_device_stats *stats = &dev->stats; - struct can_frame *cf; - struct sk_buff *skb; - - /* - * early exit if no lec update or no error. - * no lec update means that no CAN bus event has been detected - * since CPU wrote 0x7 value to status reg. - */ - if (lec_type == LEC_UNUSED || lec_type == LEC_NO_ERROR) - return 0; - - /* 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 - */ - - /* common for all type of bus errors */ - priv->can.can_stats.bus_error++; - stats->rx_errors++; - cf->can_id |= CAN_ERR_PROT | CAN_ERR_BUSERROR; - cf->data[2] |= CAN_ERR_PROT_UNSPEC; - - 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 | - CAN_ERR_PROT_LOC_ACK_DEL); - 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 | - CAN_ERR_PROT_LOC_CRC_DEL); - break; - default: - break; - } - - /* set a `lec` value so that we can check for updates later */ - priv->write_reg(priv, C_CAN_STS_REG, LEC_UNUSED); - - netif_receive_skb(skb); - stats->rx_packets++; - stats->rx_bytes += cf->can_dlc; - - return 1; -} - -static int c_can_poll(struct napi_struct *napi, int quota) -{ - u16 irqstatus; - int lec_type = 0; - int work_done = 0; - struct net_device *dev = napi->dev; - struct c_can_priv *priv = netdev_priv(dev); - - irqstatus = priv->irqstatus; - if (!irqstatus) - goto end; - - /* status events have the highest priority */ - if (irqstatus == STATUS_INTERRUPT) { - priv->current_status = priv->read_reg(priv, - C_CAN_STS_REG); - - /* handle Tx/Rx events */ - if (priv->current_status & STATUS_TXOK) - priv->write_reg(priv, C_CAN_STS_REG, - priv->current_status & ~STATUS_TXOK); - - if (priv->current_status & STATUS_RXOK) - priv->write_reg(priv, C_CAN_STS_REG, - priv->current_status & ~STATUS_RXOK); - - /* handle state changes */ - if ((priv->current_status & STATUS_EWARN) && - (!(priv->last_status & STATUS_EWARN))) { - netdev_dbg(dev, "entered error warning state\n"); - work_done += c_can_handle_state_change(dev, - C_CAN_ERROR_WARNING); - } - if ((priv->current_status & STATUS_EPASS) && - (!(priv->last_status & STATUS_EPASS))) { - netdev_dbg(dev, "entered error passive state\n"); - work_done += c_can_handle_state_change(dev, - C_CAN_ERROR_PASSIVE); - } - if ((priv->current_status & STATUS_BOFF) && - (!(priv->last_status & STATUS_BOFF))) { - netdev_dbg(dev, "entered bus off state\n"); - work_done += c_can_handle_state_change(dev, - C_CAN_BUS_OFF); - } - - /* handle bus recovery events */ - if ((!(priv->current_status & STATUS_BOFF)) && - (priv->last_status & STATUS_BOFF)) { - netdev_dbg(dev, "left bus off state\n"); - priv->can.state = CAN_STATE_ERROR_ACTIVE; - } - if ((!(priv->current_status & STATUS_EPASS)) && - (priv->last_status & STATUS_EPASS)) { - netdev_dbg(dev, "left error passive state\n"); - priv->can.state = CAN_STATE_ERROR_ACTIVE; - } - - priv->last_status = priv->current_status; - - /* handle lec errors on the bus */ - lec_type = c_can_has_and_handle_berr(priv); - if (lec_type) - work_done += c_can_handle_bus_err(dev, lec_type); - } else if ((irqstatus >= C_CAN_MSG_OBJ_RX_FIRST) && - (irqstatus <= C_CAN_MSG_OBJ_RX_LAST)) { - /* handle events corresponding to receive message objects */ - work_done += c_can_do_rx_poll(dev, (quota - work_done)); - } else if ((irqstatus >= C_CAN_MSG_OBJ_TX_FIRST) && - (irqstatus <= C_CAN_MSG_OBJ_TX_LAST)) { - /* handle events corresponding to transmit message objects */ - c_can_do_tx(dev); - } - -end: - if (work_done < quota) { - napi_complete(napi); - /* enable all IRQs */ - c_can_enable_all_interrupts(priv, ENABLE_ALL_INTERRUPTS); - } - - return work_done; -} - -static irqreturn_t c_can_isr(int irq, void *dev_id) -{ - struct net_device *dev = (struct net_device *)dev_id; - struct c_can_priv *priv = netdev_priv(dev); - - priv->irqstatus = priv->read_reg(priv, C_CAN_INT_REG); - if (!priv->irqstatus) - return IRQ_NONE; - - /* disable all interrupts and schedule the NAPI */ - c_can_enable_all_interrupts(priv, DISABLE_ALL_INTERRUPTS); - napi_schedule(&priv->napi); - - return IRQ_HANDLED; -} - -static int c_can_open(struct net_device *dev) -{ - int err; - struct c_can_priv *priv = netdev_priv(dev); - - c_can_pm_runtime_get_sync(priv); - c_can_reset_ram(priv, true); - - /* open the can device */ - err = open_candev(dev); - if (err) { - netdev_err(dev, "failed to open can device\n"); - goto exit_open_fail; - } - - /* register interrupt handler */ - err = request_irq(dev->irq, &c_can_isr, IRQF_SHARED, dev->name, - dev); - if (err < 0) { - netdev_err(dev, "failed to request interrupt\n"); - goto exit_irq_fail; - } - - napi_enable(&priv->napi); - - can_led_event(dev, CAN_LED_EVENT_OPEN); - - /* start the c_can controller */ - c_can_start(dev); - - netif_start_queue(dev); - - return 0; - -exit_irq_fail: - close_candev(dev); -exit_open_fail: - c_can_reset_ram(priv, false); - c_can_pm_runtime_put_sync(priv); - return err; -} - -static int c_can_close(struct net_device *dev) -{ - struct c_can_priv *priv = netdev_priv(dev); - - netif_stop_queue(dev); - napi_disable(&priv->napi); - c_can_stop(dev); - free_irq(dev->irq, dev); - close_candev(dev); - - c_can_reset_ram(priv, false); - c_can_pm_runtime_put_sync(priv); - - can_led_event(dev, CAN_LED_EVENT_STOP); - - return 0; -} - -struct net_device *alloc_c_can_dev(void) -{ - struct net_device *dev; - struct c_can_priv *priv; - - dev = alloc_candev(sizeof(struct c_can_priv), C_CAN_MSG_OBJ_TX_NUM); - if (!dev) - return NULL; - - priv = netdev_priv(dev); - netif_napi_add(dev, &priv->napi, c_can_poll, C_CAN_NAPI_WEIGHT); - - priv->dev = dev; - priv->can.bittiming_const = &c_can_bittiming_const; - priv->can.do_set_mode = c_can_set_mode; - priv->can.do_get_berr_counter = c_can_get_berr_counter; - priv->can.ctrlmode_supported = CAN_CTRLMODE_LOOPBACK | - CAN_CTRLMODE_LISTENONLY | - CAN_CTRLMODE_BERR_REPORTING; - - return dev; -} -EXPORT_SYMBOL_GPL(alloc_c_can_dev); - -#ifdef CONFIG_PM -int c_can_power_down(struct net_device *dev) -{ - u32 val; - unsigned long time_out; - struct c_can_priv *priv = netdev_priv(dev); - - if (!(dev->flags & IFF_UP)) - return 0; - - WARN_ON(priv->type != BOSCH_D_CAN); - - /* set PDR value so the device goes to power down mode */ - val = priv->read_reg(priv, C_CAN_CTRL_EX_REG); - val |= CONTROL_EX_PDR; - priv->write_reg(priv, C_CAN_CTRL_EX_REG, val); - - /* Wait for the PDA bit to get set */ - time_out = jiffies + msecs_to_jiffies(INIT_WAIT_MS); - while (!(priv->read_reg(priv, C_CAN_STS_REG) & STATUS_PDA) && - time_after(time_out, jiffies)) - cpu_relax(); - - if (time_after(jiffies, time_out)) - return -ETIMEDOUT; - - c_can_stop(dev); - - c_can_reset_ram(priv, false); - c_can_pm_runtime_put_sync(priv); - - return 0; -} -EXPORT_SYMBOL_GPL(c_can_power_down); - -int c_can_power_up(struct net_device *dev) -{ - u32 val; - unsigned long time_out; - struct c_can_priv *priv = netdev_priv(dev); - - if (!(dev->flags & IFF_UP)) - return 0; - - WARN_ON(priv->type != BOSCH_D_CAN); - - c_can_pm_runtime_get_sync(priv); - c_can_reset_ram(priv, true); - - /* Clear PDR and INIT bits */ - val = priv->read_reg(priv, C_CAN_CTRL_EX_REG); - val &= ~CONTROL_EX_PDR; - priv->write_reg(priv, C_CAN_CTRL_EX_REG, val); - val = priv->read_reg(priv, C_CAN_CTRL_REG); - val &= ~CONTROL_INIT; - priv->write_reg(priv, C_CAN_CTRL_REG, val); - - /* Wait for the PDA bit to get clear */ - time_out = jiffies + msecs_to_jiffies(INIT_WAIT_MS); - while ((priv->read_reg(priv, C_CAN_STS_REG) & STATUS_PDA) && - time_after(time_out, jiffies)) - cpu_relax(); - - if (time_after(jiffies, time_out)) - return -ETIMEDOUT; - - c_can_start(dev); - - return 0; -} -EXPORT_SYMBOL_GPL(c_can_power_up); -#endif - -void free_c_can_dev(struct net_device *dev) -{ - free_candev(dev); -} -EXPORT_SYMBOL_GPL(free_c_can_dev); - -static const struct net_device_ops c_can_netdev_ops = { - .ndo_open = c_can_open, - .ndo_stop = c_can_close, - .ndo_start_xmit = c_can_start_xmit, -}; - -int register_c_can_dev(struct net_device *dev) -{ - struct c_can_priv *priv = netdev_priv(dev); - int err; - - c_can_pm_runtime_enable(priv); - - dev->flags |= IFF_ECHO; /* we support local echo */ - dev->netdev_ops = &c_can_netdev_ops; - - err = register_candev(dev); - if (err) - c_can_pm_runtime_disable(priv); - else - devm_can_led_init(dev); - - return err; -} -EXPORT_SYMBOL_GPL(register_c_can_dev); - -void unregister_c_can_dev(struct net_device *dev) -{ - struct c_can_priv *priv = netdev_priv(dev); - - unregister_candev(dev); - - c_can_pm_runtime_disable(priv); -} -EXPORT_SYMBOL_GPL(unregister_c_can_dev); - -MODULE_AUTHOR("Bhupesh Sharma <bhupesh.sharma@st.com>"); -MODULE_LICENSE("GPL v2"); -MODULE_DESCRIPTION("CAN bus driver for Bosch C_CAN controller"); |