/* CAN bus driver for Holt HI3110 CAN Controller with SPI Interface * * Copyright(C) Timesys Corporation 2016 * * Based on Microchip 251x CAN Controller (mcp251x) Linux kernel driver * Copyright 2009 Christian Pellegrin EVOL S.r.l. * Copyright 2007 Raymarine UK, Ltd. All Rights Reserved. * Copyright 2006 Arcom Control Systems Ltd. * * Based on CAN bus driver for the CCAN controller written by * - Sascha Hauer, Marc Kleine-Budde, Pengutronix * - Simon Kallweit, intefo AG * Copyright 2007 * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 as * published by the Free Software Foundation. */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #define HI3110_MASTER_RESET 0x56 #define HI3110_READ_CTRL0 0xD2 #define HI3110_READ_CTRL1 0xD4 #define HI3110_READ_STATF 0xE2 #define HI3110_WRITE_CTRL0 0x14 #define HI3110_WRITE_CTRL1 0x16 #define HI3110_WRITE_INTE 0x1C #define HI3110_WRITE_BTR0 0x18 #define HI3110_WRITE_BTR1 0x1A #define HI3110_READ_BTR0 0xD6 #define HI3110_READ_BTR1 0xD8 #define HI3110_READ_INTF 0xDE #define HI3110_READ_ERR 0xDC #define HI3110_READ_FIFO_WOTIME 0x48 #define HI3110_WRITE_FIFO 0x12 #define HI3110_READ_MESSTAT 0xDA #define HI3110_READ_REC 0xEA #define HI3110_READ_TEC 0xEC #define HI3110_CTRL0_MODE_MASK (7 << 5) #define HI3110_CTRL0_NORMAL_MODE (0 << 5) #define HI3110_CTRL0_LOOPBACK_MODE (1 << 5) #define HI3110_CTRL0_MONITOR_MODE (2 << 5) #define HI3110_CTRL0_SLEEP_MODE (3 << 5) #define HI3110_CTRL0_INIT_MODE (4 << 5) #define HI3110_CTRL1_TXEN BIT(7) #define HI3110_INT_RXTMP BIT(7) #define HI3110_INT_RXFIFO BIT(6) #define HI3110_INT_TXCPLT BIT(5) #define HI3110_INT_BUSERR BIT(4) #define HI3110_INT_MCHG BIT(3) #define HI3110_INT_WAKEUP BIT(2) #define HI3110_INT_F1MESS BIT(1) #define HI3110_INT_F0MESS BIT(0) #define HI3110_ERR_BUSOFF BIT(7) #define HI3110_ERR_TXERRP BIT(6) #define HI3110_ERR_RXERRP BIT(5) #define HI3110_ERR_BITERR BIT(4) #define HI3110_ERR_FRMERR BIT(3) #define HI3110_ERR_CRCERR BIT(2) #define HI3110_ERR_ACKERR BIT(1) #define HI3110_ERR_STUFERR BIT(0) #define HI3110_ERR_PROTOCOL_MASK (0x1F) #define HI3110_ERR_PASSIVE_MASK (0x60) #define HI3110_STAT_RXFMTY BIT(1) #define HI3110_STAT_BUSOFF BIT(2) #define HI3110_STAT_ERRP BIT(3) #define HI3110_STAT_ERRW BIT(4) #define HI3110_STAT_TXMTY BIT(7) #define HI3110_BTR0_SJW_SHIFT 6 #define HI3110_BTR0_BRP_SHIFT 0 #define HI3110_BTR1_SAMP_3PERBIT (1 << 7) #define HI3110_BTR1_SAMP_1PERBIT (0 << 7) #define HI3110_BTR1_TSEG2_SHIFT 4 #define HI3110_BTR1_TSEG1_SHIFT 0 #define HI3110_FIFO_WOTIME_TAG_OFF 0 #define HI3110_FIFO_WOTIME_ID_OFF 1 #define HI3110_FIFO_WOTIME_DLC_OFF 5 #define HI3110_FIFO_WOTIME_DAT_OFF 6 #define HI3110_FIFO_WOTIME_TAG_IDE BIT(7) #define HI3110_FIFO_WOTIME_ID_RTR BIT(0) #define HI3110_FIFO_TAG_OFF 0 #define HI3110_FIFO_ID_OFF 1 #define HI3110_FIFO_STD_DLC_OFF 3 #define HI3110_FIFO_STD_DATA_OFF 4 #define HI3110_FIFO_EXT_DLC_OFF 5 #define HI3110_FIFO_EXT_DATA_OFF 6 #define HI3110_CAN_MAX_DATA_LEN 8 #define HI3110_RX_BUF_LEN 15 #define HI3110_TX_STD_BUF_LEN 12 #define HI3110_TX_EXT_BUF_LEN 14 #define HI3110_CAN_FRAME_MAX_BITS 128 #define HI3110_EFF_FLAGS 0x18 /* IDE + SRR */ #define HI3110_TX_ECHO_SKB_MAX 1 #define HI3110_OST_DELAY_MS (10) #define DEVICE_NAME "hi3110" static int hi3110_enable_dma = 1; /* Enable SPI DMA. Default: 1 (On) */ module_param(hi3110_enable_dma, int, 0444); MODULE_PARM_DESC(hi3110_enable_dma, "Enable SPI DMA. Default: 1 (On)"); static const struct can_bittiming_const hi3110_bittiming_const = { .name = DEVICE_NAME, .tseg1_min = 2, .tseg1_max = 16, .tseg2_min = 2, .tseg2_max = 8, .sjw_max = 4, .brp_min = 1, .brp_max = 64, .brp_inc = 1, }; enum hi3110_model { CAN_HI3110_HI3110 = 0x3110, }; struct hi3110_priv { struct can_priv can; struct net_device *net; struct spi_device *spi; enum hi3110_model model; struct mutex hi3110_lock; /* SPI device lock */ u8 *spi_tx_buf; u8 *spi_rx_buf; dma_addr_t spi_tx_dma; dma_addr_t spi_rx_dma; struct sk_buff *tx_skb; int tx_len; struct workqueue_struct *wq; struct work_struct tx_work; struct work_struct restart_work; int force_quit; int after_suspend; #define HI3110_AFTER_SUSPEND_UP 1 #define HI3110_AFTER_SUSPEND_DOWN 2 #define HI3110_AFTER_SUSPEND_POWER 4 #define HI3110_AFTER_SUSPEND_RESTART 8 int restart_tx; struct regulator *power; struct regulator *transceiver; struct clk *clk; }; static void hi3110_clean(struct net_device *net) { struct hi3110_priv *priv = netdev_priv(net); if (priv->tx_skb || priv->tx_len) net->stats.tx_errors++; if (priv->tx_skb) dev_kfree_skb(priv->tx_skb); if (priv->tx_len) can_free_echo_skb(priv->net, 0); priv->tx_skb = NULL; priv->tx_len = 0; } /* Note about handling of error return of hi3110_spi_trans: accessing * registers via SPI is not really different conceptually than using * normal I/O assembler instructions, although it's much more * complicated from a practical POV. So it's not advisable to always * check the return value of this function. Imagine that every * read{b,l}, write{b,l} and friends would be bracketed in "if ( < 0) * error();", it would be a great mess (well there are some situation * when exception handling C++ like could be useful after all). So we * just check that transfers are OK at the beginning of our * conversation with the chip and to avoid doing really nasty things * (like injecting bogus packets in the network stack). */ static int hi3110_spi_trans(struct spi_device *spi, int len) { struct hi3110_priv *priv = spi_get_drvdata(spi); struct spi_transfer t = { .tx_buf = priv->spi_tx_buf, .rx_buf = priv->spi_rx_buf, .len = len, .cs_change = 0, }; struct spi_message m; int ret; spi_message_init(&m); if (hi3110_enable_dma) { t.tx_dma = priv->spi_tx_dma; t.rx_dma = priv->spi_rx_dma; m.is_dma_mapped = 1; } spi_message_add_tail(&t, &m); ret = spi_sync(spi, &m); if (ret) dev_err(&spi->dev, "spi transfer failed: ret = %d\n", ret); return ret; } static int hi3110_cmd(struct spi_device *spi, u8 command) { struct hi3110_priv *priv = spi_get_drvdata(spi); priv->spi_tx_buf[0] = command; dev_dbg(&spi->dev, "hi3110_cmd: %02X\n", command); return hi3110_spi_trans(spi, 1); } static u8 hi3110_read(struct spi_device *spi, u8 command) { struct hi3110_priv *priv = spi_get_drvdata(spi); u8 val = 0; priv->spi_tx_buf[0] = command; hi3110_spi_trans(spi, 2); val = priv->spi_rx_buf[1]; return val; } static void hi3110_write(struct spi_device *spi, u8 reg, u8 val) { struct hi3110_priv *priv = spi_get_drvdata(spi); priv->spi_tx_buf[0] = reg; priv->spi_tx_buf[1] = val; hi3110_spi_trans(spi, 2); } static void hi3110_hw_tx_frame(struct spi_device *spi, u8 *buf, int len) { struct hi3110_priv *priv = spi_get_drvdata(spi); priv->spi_tx_buf[0] = HI3110_WRITE_FIFO; memcpy(priv->spi_tx_buf + 1, buf, len); hi3110_spi_trans(spi, len + 1); } static void hi3110_hw_tx(struct spi_device *spi, struct can_frame *frame) { u8 buf[HI3110_TX_EXT_BUF_LEN]; buf[HI3110_FIFO_TAG_OFF] = 0; if (frame->can_id & CAN_EFF_FLAG) { /* Extended frame */ buf[HI3110_FIFO_ID_OFF] = (frame->can_id & CAN_EFF_MASK) >> 21; buf[HI3110_FIFO_ID_OFF + 1] = (((frame->can_id & CAN_EFF_MASK) >> 13) & 0xe0) | HI3110_EFF_FLAGS | (((frame->can_id & CAN_EFF_MASK) >> 15) & 0x07); buf[HI3110_FIFO_ID_OFF + 2] = (frame->can_id & CAN_EFF_MASK) >> 7; buf[HI3110_FIFO_ID_OFF + 3] = ((frame->can_id & CAN_EFF_MASK) << 1) | ((frame->can_id & CAN_RTR_FLAG) ? 1 : 0); buf[HI3110_FIFO_EXT_DLC_OFF] = frame->can_dlc; memcpy(buf + HI3110_FIFO_EXT_DATA_OFF, frame->data, frame->can_dlc); hi3110_hw_tx_frame(spi, buf, HI3110_TX_EXT_BUF_LEN - (HI3110_CAN_MAX_DATA_LEN - frame->can_dlc)); } else { /* Standard frame */ buf[HI3110_FIFO_ID_OFF] = (frame->can_id & CAN_SFF_MASK) >> 3; buf[HI3110_FIFO_ID_OFF + 1] = ((frame->can_id & CAN_SFF_MASK) << 5) | ((frame->can_id & CAN_RTR_FLAG) ? (1 << 4) : 0); buf[HI3110_FIFO_STD_DLC_OFF] = frame->can_dlc; memcpy(buf + HI3110_FIFO_STD_DATA_OFF, frame->data, frame->can_dlc); hi3110_hw_tx_frame(spi, buf, HI3110_TX_STD_BUF_LEN - (HI3110_CAN_MAX_DATA_LEN - frame->can_dlc)); } } static void hi3110_hw_rx_frame(struct spi_device *spi, u8 *buf) { struct hi3110_priv *priv = spi_get_drvdata(spi); priv->spi_tx_buf[0] = HI3110_READ_FIFO_WOTIME; hi3110_spi_trans(spi, HI3110_RX_BUF_LEN); memcpy(buf, priv->spi_rx_buf + 1, HI3110_RX_BUF_LEN - 1); } static void hi3110_hw_rx(struct spi_device *spi) { struct hi3110_priv *priv = spi_get_drvdata(spi); struct sk_buff *skb; struct can_frame *frame; u8 buf[HI3110_RX_BUF_LEN - 1]; skb = alloc_can_skb(priv->net, &frame); if (!skb) { priv->net->stats.rx_dropped++; return; } hi3110_hw_rx_frame(spi, buf); if (buf[HI3110_FIFO_WOTIME_TAG_OFF] & HI3110_FIFO_WOTIME_TAG_IDE) { /* IDE is recessive (1), indicating extended 29-bit frame */ frame->can_id = CAN_EFF_FLAG; frame->can_id |= (buf[HI3110_FIFO_WOTIME_ID_OFF] << 21) | (((buf[HI3110_FIFO_WOTIME_ID_OFF + 1] & 0xE0) >> 5) << 18) | ((buf[HI3110_FIFO_WOTIME_ID_OFF + 1] & 0x07) << 15) | (buf[HI3110_FIFO_WOTIME_ID_OFF + 2] << 7) | (buf[HI3110_FIFO_WOTIME_ID_OFF + 3] >> 1); } else { /* IDE is dominant (0), frame indicating standard 11-bit */ frame->can_id = (buf[HI3110_FIFO_WOTIME_ID_OFF] << 3) | ((buf[HI3110_FIFO_WOTIME_ID_OFF + 1] & 0xE0) >> 5); } /* Data length */ frame->can_dlc = get_can_dlc(buf[HI3110_FIFO_WOTIME_DLC_OFF] & 0x0F); if (buf[HI3110_FIFO_WOTIME_ID_OFF + 3] & HI3110_FIFO_WOTIME_ID_RTR) frame->can_id |= CAN_RTR_FLAG; else memcpy(frame->data, buf + HI3110_FIFO_WOTIME_DAT_OFF, frame->can_dlc); priv->net->stats.rx_packets++; priv->net->stats.rx_bytes += frame->can_dlc; can_led_event(priv->net, CAN_LED_EVENT_RX); netif_rx_ni(skb); } static void hi3110_hw_sleep(struct spi_device *spi) { hi3110_write(spi, HI3110_WRITE_CTRL0, HI3110_CTRL0_SLEEP_MODE); } static netdev_tx_t hi3110_hard_start_xmit(struct sk_buff *skb, struct net_device *net) { struct hi3110_priv *priv = netdev_priv(net); struct spi_device *spi = priv->spi; if (priv->tx_skb || priv->tx_len) { dev_err(&spi->dev, "hard_xmit called while tx busy\n"); return NETDEV_TX_BUSY; } if (can_dropped_invalid_skb(net, skb)) return NETDEV_TX_OK; netif_stop_queue(net); priv->tx_skb = skb; queue_work(priv->wq, &priv->tx_work); return NETDEV_TX_OK; } static int hi3110_do_set_mode(struct net_device *net, enum can_mode mode) { struct hi3110_priv *priv = netdev_priv(net); switch (mode) { case CAN_MODE_START: hi3110_clean(net); /* We have to delay work since SPI I/O may sleep */ priv->can.state = CAN_STATE_ERROR_ACTIVE; priv->restart_tx = 1; if (priv->can.restart_ms == 0) priv->after_suspend = HI3110_AFTER_SUSPEND_RESTART; queue_work(priv->wq, &priv->restart_work); break; default: return -EOPNOTSUPP; } return 0; } static int hi3110_get_berr_counter(const struct net_device *net, struct can_berr_counter *bec) { struct hi3110_priv *priv = netdev_priv(net); struct spi_device *spi = priv->spi; mutex_lock(&priv->hi3110_lock); bec->txerr = hi3110_read(spi, HI3110_READ_TEC); bec->rxerr = hi3110_read(spi, HI3110_READ_REC); mutex_unlock(&priv->hi3110_lock); return 0; } static int hi3110_set_normal_mode(struct spi_device *spi) { struct hi3110_priv *priv = spi_get_drvdata(spi); u8 reg = 0; hi3110_write(spi, HI3110_WRITE_INTE, HI3110_INT_BUSERR | HI3110_INT_RXFIFO | HI3110_INT_TXCPLT); /* Enable TX */ hi3110_write(spi, HI3110_WRITE_CTRL1, HI3110_CTRL1_TXEN); if (priv->can.ctrlmode & CAN_CTRLMODE_LOOPBACK) reg = HI3110_CTRL0_LOOPBACK_MODE; else if (priv->can.ctrlmode & CAN_CTRLMODE_LISTENONLY) reg = HI3110_CTRL0_MONITOR_MODE; else reg = HI3110_CTRL0_NORMAL_MODE; hi3110_write(spi, HI3110_WRITE_CTRL0, reg); /* Wait for the device to enter the mode */ mdelay(HI3110_OST_DELAY_MS); reg = hi3110_read(spi, HI3110_READ_CTRL0); if ((reg & HI3110_CTRL0_MODE_MASK) != reg) return -EBUSY; priv->can.state = CAN_STATE_ERROR_ACTIVE; return 0; } static int hi3110_do_set_bittiming(struct net_device *net) { struct hi3110_priv *priv = netdev_priv(net); struct can_bittiming *bt = &priv->can.bittiming; struct spi_device *spi = priv->spi; hi3110_write(spi, HI3110_WRITE_BTR0, ((bt->sjw - 1) << HI3110_BTR0_SJW_SHIFT) | ((bt->brp - 1) << HI3110_BTR0_BRP_SHIFT)); hi3110_write(spi, HI3110_WRITE_BTR1, (priv->can.ctrlmode & CAN_CTRLMODE_3_SAMPLES ? HI3110_BTR1_SAMP_3PERBIT : HI3110_BTR1_SAMP_1PERBIT) | ((bt->phase_seg1 + bt->prop_seg - 1) << HI3110_BTR1_TSEG1_SHIFT) | ((bt->phase_seg2 - 1) << HI3110_BTR1_TSEG2_SHIFT)); dev_dbg(&spi->dev, "BT: 0x%02x 0x%02x\n", hi3110_read(spi, HI3110_READ_BTR0), hi3110_read(spi, HI3110_READ_BTR1)); return 0; } static int hi3110_setup(struct net_device *net) { hi3110_do_set_bittiming(net); return 0; } static int hi3110_hw_reset(struct spi_device *spi) { u8 reg; int ret; /* Wait for oscillator startup timer after power up */ mdelay(HI3110_OST_DELAY_MS); ret = hi3110_cmd(spi, HI3110_MASTER_RESET); if (ret) return ret; /* Wait for oscillator startup timer after reset */ mdelay(HI3110_OST_DELAY_MS); reg = hi3110_read(spi, HI3110_READ_CTRL0); if ((reg & HI3110_CTRL0_MODE_MASK) != HI3110_CTRL0_INIT_MODE) return -ENODEV; /* As per the datasheet it appears the error flags are * not cleared on reset. Explicitly clear them by performing a read */ hi3110_read(spi, HI3110_READ_ERR); return 0; } static int hi3110_hw_probe(struct spi_device *spi) { u8 statf; hi3110_hw_reset(spi); /* Confirm correct operation by checking against reset values * in datasheet */ statf = hi3110_read(spi, HI3110_READ_STATF); dev_dbg(&spi->dev, "statf: %02X\n", statf); if (statf != 0x82) return -ENODEV; return 0; } static int hi3110_power_enable(struct regulator *reg, int enable) { if (IS_ERR_OR_NULL(reg)) return 0; if (enable) return regulator_enable(reg); else return regulator_disable(reg); } static int hi3110_stop(struct net_device *net) { struct hi3110_priv *priv = netdev_priv(net); struct spi_device *spi = priv->spi; close_candev(net); priv->force_quit = 1; free_irq(spi->irq, priv); destroy_workqueue(priv->wq); priv->wq = NULL; mutex_lock(&priv->hi3110_lock); /* Disable transmit, interrupts and clear flags */ hi3110_write(spi, HI3110_WRITE_CTRL1, 0x0); hi3110_write(spi, HI3110_WRITE_INTE, 0x0); hi3110_read(spi, HI3110_READ_INTF); hi3110_clean(net); hi3110_hw_sleep(spi); hi3110_power_enable(priv->transceiver, 0); priv->can.state = CAN_STATE_STOPPED; mutex_unlock(&priv->hi3110_lock); can_led_event(net, CAN_LED_EVENT_STOP); return 0; } static void hi3110_tx_work_handler(struct work_struct *ws) { struct hi3110_priv *priv = container_of(ws, struct hi3110_priv, tx_work); struct spi_device *spi = priv->spi; struct net_device *net = priv->net; struct can_frame *frame; mutex_lock(&priv->hi3110_lock); if (priv->tx_skb) { if (priv->can.state == CAN_STATE_BUS_OFF) { hi3110_clean(net); } else { frame = (struct can_frame *)priv->tx_skb->data; hi3110_hw_tx(spi, frame); priv->tx_len = 1 + frame->can_dlc; can_put_echo_skb(priv->tx_skb, net, 0); priv->tx_skb = NULL; } } mutex_unlock(&priv->hi3110_lock); } static void hi3110_restart_work_handler(struct work_struct *ws) { struct hi3110_priv *priv = container_of(ws, struct hi3110_priv, restart_work); struct spi_device *spi = priv->spi; struct net_device *net = priv->net; mutex_lock(&priv->hi3110_lock); if (priv->after_suspend) { hi3110_hw_reset(spi); hi3110_setup(net); if (priv->after_suspend & HI3110_AFTER_SUSPEND_RESTART) { hi3110_set_normal_mode(spi); } else if (priv->after_suspend & HI3110_AFTER_SUSPEND_UP) { netif_device_attach(net); hi3110_clean(net); hi3110_set_normal_mode(spi); netif_wake_queue(net); } else { hi3110_hw_sleep(spi); } priv->after_suspend = 0; priv->force_quit = 0; } if (priv->restart_tx) { priv->restart_tx = 0; hi3110_hw_reset(spi); hi3110_setup(net); hi3110_clean(net); hi3110_set_normal_mode(spi); netif_wake_queue(net); } mutex_unlock(&priv->hi3110_lock); } static irqreturn_t hi3110_can_ist(int irq, void *dev_id) { struct hi3110_priv *priv = dev_id; struct spi_device *spi = priv->spi; struct net_device *net = priv->net; mutex_lock(&priv->hi3110_lock); while (!priv->force_quit) { enum can_state new_state; u8 intf, eflag, statf; while (!(HI3110_STAT_RXFMTY & (statf = hi3110_read(spi, HI3110_READ_STATF)))) { hi3110_hw_rx(spi); } intf = hi3110_read(spi, HI3110_READ_INTF); eflag = hi3110_read(spi, HI3110_READ_ERR); /* Update can state */ if (eflag & HI3110_ERR_BUSOFF) new_state = CAN_STATE_BUS_OFF; else if (eflag & HI3110_ERR_PASSIVE_MASK) new_state = CAN_STATE_ERROR_PASSIVE; else if (statf & HI3110_STAT_ERRW) new_state = CAN_STATE_ERROR_WARNING; else new_state = CAN_STATE_ERROR_ACTIVE; if (new_state != priv->can.state) { struct can_frame *cf; struct sk_buff *skb; enum can_state rx_state, tx_state; u8 rxerr, txerr; skb = alloc_can_err_skb(net, &cf); if (!skb) break; txerr = hi3110_read(spi, HI3110_READ_TEC); rxerr = hi3110_read(spi, HI3110_READ_REC); tx_state = txerr >= rxerr ? new_state : 0; rx_state = txerr <= rxerr ? new_state : 0; can_change_state(net, cf, tx_state, rx_state); netif_rx_ni(skb); if (new_state == CAN_STATE_BUS_OFF) { can_bus_off(net); if (priv->can.restart_ms == 0) { priv->force_quit = 1; hi3110_hw_sleep(spi); break; } } else { cf->data[6] = txerr; cf->data[7] = rxerr; } } /* Update bus errors */ if ((intf & HI3110_INT_BUSERR) && (priv->can.ctrlmode & CAN_CTRLMODE_BERR_REPORTING)) { struct can_frame *cf; struct sk_buff *skb; /* Check for protocol errors */ if (eflag & HI3110_ERR_PROTOCOL_MASK) { skb = alloc_can_err_skb(net, &cf); if (!skb) break; cf->can_id |= CAN_ERR_PROT | CAN_ERR_BUSERROR; priv->can.can_stats.bus_error++; priv->net->stats.rx_errors++; if (eflag & HI3110_ERR_BITERR) cf->data[2] |= CAN_ERR_PROT_BIT; else if (eflag & HI3110_ERR_FRMERR) cf->data[2] |= CAN_ERR_PROT_FORM; else if (eflag & HI3110_ERR_STUFERR) cf->data[2] |= CAN_ERR_PROT_STUFF; else if (eflag & HI3110_ERR_CRCERR) cf->data[3] |= CAN_ERR_PROT_LOC_CRC_SEQ; else if (eflag & HI3110_ERR_ACKERR) cf->data[3] |= CAN_ERR_PROT_LOC_ACK; cf->data[6] = hi3110_read(spi, HI3110_READ_TEC); cf->data[7] = hi3110_read(spi, HI3110_READ_REC); netdev_dbg(priv->net, "Bus Error\n"); netif_rx_ni(skb); } } if (priv->tx_len && statf & HI3110_STAT_TXMTY) { net->stats.tx_packets++; net->stats.tx_bytes += priv->tx_len - 1; can_led_event(net, CAN_LED_EVENT_TX); if (priv->tx_len) { can_get_echo_skb(net, 0); priv->tx_len = 0; } netif_wake_queue(net); } if (intf == 0) break; } mutex_unlock(&priv->hi3110_lock); return IRQ_HANDLED; } static int hi3110_open(struct net_device *net) { struct hi3110_priv *priv = netdev_priv(net); struct spi_device *spi = priv->spi; unsigned long flags = IRQF_ONESHOT | IRQF_TRIGGER_HIGH; int ret; ret = open_candev(net); if (ret) return ret; mutex_lock(&priv->hi3110_lock); hi3110_power_enable(priv->transceiver, 1); priv->force_quit = 0; priv->tx_skb = NULL; priv->tx_len = 0; ret = request_threaded_irq(spi->irq, NULL, hi3110_can_ist, flags, DEVICE_NAME, priv); if (ret) { dev_err(&spi->dev, "failed to acquire irq %d\n", spi->irq); goto out_close; } priv->wq = alloc_workqueue("hi3110_wq", WQ_FREEZABLE | WQ_MEM_RECLAIM, 0); if (!priv->wq) { ret = -ENOMEM; goto out_free_irq; } INIT_WORK(&priv->tx_work, hi3110_tx_work_handler); INIT_WORK(&priv->restart_work, hi3110_restart_work_handler); ret = hi3110_hw_reset(spi); if (ret) goto out_free_wq; ret = hi3110_setup(net); if (ret) goto out_free_wq; ret = hi3110_set_normal_mode(spi); if (ret) goto out_free_wq; can_led_event(net, CAN_LED_EVENT_OPEN); netif_wake_queue(net); mutex_unlock(&priv->hi3110_lock); return 0; out_free_wq: destroy_workqueue(priv->wq); out_free_irq: free_irq(spi->irq, priv); hi3110_hw_sleep(spi); out_close: hi3110_power_enable(priv->transceiver, 0); close_candev(net); mutex_unlock(&priv->hi3110_lock); return ret; } static const struct net_device_ops hi3110_netdev_ops = { .ndo_open = hi3110_open, .ndo_stop = hi3110_stop, .ndo_start_xmit = hi3110_hard_start_xmit, }; static const struct of_device_id hi3110_of_match[] = { { .compatible = "holt,hi3110", .data = (void *)CAN_HI3110_HI3110, }, { } }; MODULE_DEVICE_TABLE(of, hi3110_of_match); static const struct spi_device_id hi3110_id_table[] = { { .name = "hi3110", .driver_data = (kernel_ulong_t)CAN_HI3110_HI3110, }, { } }; MODULE_DEVICE_TABLE(spi, hi3110_id_table); static int hi3110_can_probe(struct spi_device *spi) { const struct of_device_id *of_id = of_match_device(hi3110_of_match, &spi->dev); struct net_device *net; struct hi3110_priv *priv; struct clk *clk; int freq, ret; clk = devm_clk_get(&spi->dev, NULL); if (IS_ERR(clk)) { dev_err(&spi->dev, "no CAN clock source defined\n"); return PTR_ERR(clk); } freq = clk_get_rate(clk); /* Sanity check */ if (freq > 40000000) return -ERANGE; /* Allocate can/net device */ net = alloc_candev(sizeof(struct hi3110_priv), HI3110_TX_ECHO_SKB_MAX); if (!net) return -ENOMEM; if (!IS_ERR(clk)) { ret = clk_prepare_enable(clk); if (ret) goto out_free; } net->netdev_ops = &hi3110_netdev_ops; net->flags |= IFF_ECHO; priv = netdev_priv(net); priv->can.bittiming_const = &hi3110_bittiming_const; priv->can.do_set_mode = hi3110_do_set_mode; priv->can.do_get_berr_counter = hi3110_get_berr_counter; priv->can.clock.freq = freq / 2; priv->can.ctrlmode_supported = CAN_CTRLMODE_3_SAMPLES | CAN_CTRLMODE_LOOPBACK | CAN_CTRLMODE_LISTENONLY | CAN_CTRLMODE_BERR_REPORTING; if (of_id) priv->model = (enum hi3110_model)of_id->data; else priv->model = spi_get_device_id(spi)->driver_data; priv->net = net; priv->clk = clk; spi_set_drvdata(spi, priv); /* Configure the SPI bus */ spi->bits_per_word = 8; ret = spi_setup(spi); if (ret) goto out_clk; priv->power = devm_regulator_get_optional(&spi->dev, "vdd"); priv->transceiver = devm_regulator_get_optional(&spi->dev, "xceiver"); if ((PTR_ERR(priv->power) == -EPROBE_DEFER) || (PTR_ERR(priv->transceiver) == -EPROBE_DEFER)) { ret = -EPROBE_DEFER; goto out_clk; } ret = hi3110_power_enable(priv->power, 1); if (ret) goto out_clk; priv->spi = spi; mutex_init(&priv->hi3110_lock); /* If requested, allocate DMA buffers */ if (hi3110_enable_dma) { spi->dev.coherent_dma_mask = ~0; /* Minimum coherent DMA allocation is PAGE_SIZE, so allocate * that much and share it between Tx and Rx DMA buffers. */ priv->spi_tx_buf = dmam_alloc_coherent(&spi->dev, PAGE_SIZE, &priv->spi_tx_dma, GFP_DMA); if (priv->spi_tx_buf) { priv->spi_rx_buf = (priv->spi_tx_buf + (PAGE_SIZE / 2)); priv->spi_rx_dma = (dma_addr_t)(priv->spi_tx_dma + (PAGE_SIZE / 2)); } else { /* Fall back to non-DMA */ hi3110_enable_dma = 0; } } /* Allocate non-DMA buffers */ if (!hi3110_enable_dma) { priv->spi_tx_buf = devm_kzalloc(&spi->dev, HI3110_RX_BUF_LEN, GFP_KERNEL); if (!priv->spi_tx_buf) { ret = -ENOMEM; goto error_probe; } priv->spi_rx_buf = devm_kzalloc(&spi->dev, HI3110_RX_BUF_LEN, GFP_KERNEL); if (!priv->spi_rx_buf) { ret = -ENOMEM; goto error_probe; } } SET_NETDEV_DEV(net, &spi->dev); ret = hi3110_hw_probe(spi); if (ret) { if (ret == -ENODEV) dev_err(&spi->dev, "Cannot initialize %x. Wrong wiring?\n", priv->model); goto error_probe; } hi3110_hw_sleep(spi); ret = register_candev(net); if (ret) goto error_probe; devm_can_led_init(net); netdev_info(net, "%x successfully initialized.\n", priv->model); return 0; error_probe: hi3110_power_enable(priv->power, 0); out_clk: if (!IS_ERR(clk)) clk_disable_unprepare(clk); out_free: free_candev(net); dev_err(&spi->dev, "Probe failed, err=%d\n", -ret); return ret; } static int hi3110_can_remove(struct spi_device *spi) { struct hi3110_priv *priv = spi_get_drvdata(spi); struct net_device *net = priv->net; unregister_candev(net); hi3110_power_enable(priv->power, 0); if (!IS_ERR(priv->clk)) clk_disable_unprepare(priv->clk); free_candev(net); return 0; } static int __maybe_unused hi3110_can_suspend(struct device *dev) { struct spi_device *spi = to_spi_device(dev); struct hi3110_priv *priv = spi_get_drvdata(spi); struct net_device *net = priv->net; priv->force_quit = 1; disable_irq(spi->irq); /* Note: at this point neither IST nor workqueues are running. * open/stop cannot be called anyway so locking is not needed */ if (netif_running(net)) { netif_device_detach(net); hi3110_hw_sleep(spi); hi3110_power_enable(priv->transceiver, 0); priv->after_suspend = HI3110_AFTER_SUSPEND_UP; } else { priv->after_suspend = HI3110_AFTER_SUSPEND_DOWN; } if (!IS_ERR_OR_NULL(priv->power)) { regulator_disable(priv->power); priv->after_suspend |= HI3110_AFTER_SUSPEND_POWER; } return 0; } static int __maybe_unused hi3110_can_resume(struct device *dev) { struct spi_device *spi = to_spi_device(dev); struct hi3110_priv *priv = spi_get_drvdata(spi); if (priv->after_suspend & HI3110_AFTER_SUSPEND_POWER) hi3110_power_enable(priv->power, 1); if (priv->after_suspend & HI3110_AFTER_SUSPEND_UP) { hi3110_power_enable(priv->transceiver, 1); queue_work(priv->wq, &priv->restart_work); } else { priv->after_suspend = 0; } priv->force_quit = 0; enable_irq(spi->irq); return 0; } static SIMPLE_DEV_PM_OPS(hi3110_can_pm_ops, hi3110_can_suspend, hi3110_can_resume); static struct spi_driver hi3110_can_driver = { .driver = { .name = DEVICE_NAME, .of_match_table = hi3110_of_match, .pm = &hi3110_can_pm_ops, }, .id_table = hi3110_id_table, .probe = hi3110_can_probe, .remove = hi3110_can_remove, }; module_spi_driver(hi3110_can_driver); MODULE_AUTHOR("Akshay Bhat "); MODULE_AUTHOR("Casey Fitzpatrick "); MODULE_DESCRIPTION("Holt HI-3110 CAN driver"); MODULE_LICENSE("GPL v2");