v4.19.13 snapshot.
diff --git a/drivers/net/can/spi/Kconfig b/drivers/net/can/spi/Kconfig
new file mode 100644
index 0000000..8f2e0dd
--- /dev/null
+++ b/drivers/net/can/spi/Kconfig
@@ -0,0 +1,16 @@
+menu "CAN SPI interfaces"
+ depends on SPI
+
+config CAN_HI311X
+ tristate "Holt HI311x SPI CAN controllers"
+ depends on CAN_DEV && SPI && HAS_DMA
+ ---help---
+ Driver for the Holt HI311x SPI CAN controllers.
+
+config CAN_MCP251X
+ tristate "Microchip MCP251x SPI CAN controllers"
+ depends on HAS_DMA
+ ---help---
+ Driver for the Microchip MCP251x SPI CAN controllers.
+
+endmenu
diff --git a/drivers/net/can/spi/Makefile b/drivers/net/can/spi/Makefile
new file mode 100644
index 0000000..f59fa37
--- /dev/null
+++ b/drivers/net/can/spi/Makefile
@@ -0,0 +1,7 @@
+#
+# Makefile for the Linux Controller Area Network SPI drivers.
+#
+
+
+obj-$(CONFIG_CAN_HI311X) += hi311x.o
+obj-$(CONFIG_CAN_MCP251X) += mcp251x.o
diff --git a/drivers/net/can/spi/hi311x.c b/drivers/net/can/spi/hi311x.c
new file mode 100644
index 0000000..ddaf462
--- /dev/null
+++ b/drivers/net/can/spi/hi311x.c
@@ -0,0 +1,1079 @@
+/* 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 <linux/can/core.h>
+#include <linux/can/dev.h>
+#include <linux/can/led.h>
+#include <linux/clk.h>
+#include <linux/completion.h>
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/dma-mapping.h>
+#include <linux/freezer.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/netdevice.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/regulator/consumer.h>
+#include <linux/slab.h>
+#include <linux/spi/spi.h>
+#include <linux/uaccess.h>
+
+#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 u8 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);
+ cf->data[6] = txerr;
+ cf->data[7] = rxerr;
+ 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;
+ }
+ }
+ }
+
+ /* 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 <akshay.bhat@timesys.com>");
+MODULE_AUTHOR("Casey Fitzpatrick <casey.fitzpatrick@timesys.com>");
+MODULE_DESCRIPTION("Holt HI-3110 CAN driver");
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/net/can/spi/mcp251x.c b/drivers/net/can/spi/mcp251x.c
new file mode 100644
index 0000000..e908176
--- /dev/null
+++ b/drivers/net/can/spi/mcp251x.c
@@ -0,0 +1,1263 @@
+/*
+ * CAN bus driver for Microchip 251x CAN Controller with SPI Interface
+ *
+ * MCP2510 support and bug fixes by Christian Pellegrin
+ * <chripell@evolware.org>
+ *
+ * Copyright 2009 Christian Pellegrin EVOL S.r.l.
+ *
+ * Copyright 2007 Raymarine UK, Ltd. All Rights Reserved.
+ * Written under contract by:
+ * Chris Elston, Katalix Systems, Ltd.
+ *
+ * Based on Microchip MCP251x CAN controller driver written by
+ * David Vrabel, 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 version 2 of the GNU General Public License
+ * as published by the Free Software Foundation
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, see <http://www.gnu.org/licenses/>.
+ *
+ *
+ *
+ * Your platform definition file should specify something like:
+ *
+ * static struct mcp251x_platform_data mcp251x_info = {
+ * .oscillator_frequency = 8000000,
+ * };
+ *
+ * static struct spi_board_info spi_board_info[] = {
+ * {
+ * .modalias = "mcp2510",
+ * // or "mcp2515" depending on your controller
+ * .platform_data = &mcp251x_info,
+ * .irq = IRQ_EINT13,
+ * .max_speed_hz = 2*1000*1000,
+ * .chip_select = 2,
+ * },
+ * };
+ *
+ * Please see mcp251x.h for a description of the fields in
+ * struct mcp251x_platform_data.
+ *
+ */
+
+#include <linux/can/core.h>
+#include <linux/can/dev.h>
+#include <linux/can/led.h>
+#include <linux/can/platform/mcp251x.h>
+#include <linux/clk.h>
+#include <linux/completion.h>
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/dma-mapping.h>
+#include <linux/freezer.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/netdevice.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/spi/spi.h>
+#include <linux/uaccess.h>
+#include <linux/regulator/consumer.h>
+
+/* SPI interface instruction set */
+#define INSTRUCTION_WRITE 0x02
+#define INSTRUCTION_READ 0x03
+#define INSTRUCTION_BIT_MODIFY 0x05
+#define INSTRUCTION_LOAD_TXB(n) (0x40 + 2 * (n))
+#define INSTRUCTION_READ_RXB(n) (((n) == 0) ? 0x90 : 0x94)
+#define INSTRUCTION_RESET 0xC0
+#define RTS_TXB0 0x01
+#define RTS_TXB1 0x02
+#define RTS_TXB2 0x04
+#define INSTRUCTION_RTS(n) (0x80 | ((n) & 0x07))
+
+
+/* MPC251x registers */
+#define CANSTAT 0x0e
+#define CANCTRL 0x0f
+# define CANCTRL_REQOP_MASK 0xe0
+# define CANCTRL_REQOP_CONF 0x80
+# define CANCTRL_REQOP_LISTEN_ONLY 0x60
+# define CANCTRL_REQOP_LOOPBACK 0x40
+# define CANCTRL_REQOP_SLEEP 0x20
+# define CANCTRL_REQOP_NORMAL 0x00
+# define CANCTRL_OSM 0x08
+# define CANCTRL_ABAT 0x10
+#define TEC 0x1c
+#define REC 0x1d
+#define CNF1 0x2a
+# define CNF1_SJW_SHIFT 6
+#define CNF2 0x29
+# define CNF2_BTLMODE 0x80
+# define CNF2_SAM 0x40
+# define CNF2_PS1_SHIFT 3
+#define CNF3 0x28
+# define CNF3_SOF 0x08
+# define CNF3_WAKFIL 0x04
+# define CNF3_PHSEG2_MASK 0x07
+#define CANINTE 0x2b
+# define CANINTE_MERRE 0x80
+# define CANINTE_WAKIE 0x40
+# define CANINTE_ERRIE 0x20
+# define CANINTE_TX2IE 0x10
+# define CANINTE_TX1IE 0x08
+# define CANINTE_TX0IE 0x04
+# define CANINTE_RX1IE 0x02
+# define CANINTE_RX0IE 0x01
+#define CANINTF 0x2c
+# define CANINTF_MERRF 0x80
+# define CANINTF_WAKIF 0x40
+# define CANINTF_ERRIF 0x20
+# define CANINTF_TX2IF 0x10
+# define CANINTF_TX1IF 0x08
+# define CANINTF_TX0IF 0x04
+# define CANINTF_RX1IF 0x02
+# define CANINTF_RX0IF 0x01
+# define CANINTF_RX (CANINTF_RX0IF | CANINTF_RX1IF)
+# define CANINTF_TX (CANINTF_TX2IF | CANINTF_TX1IF | CANINTF_TX0IF)
+# define CANINTF_ERR (CANINTF_ERRIF)
+#define EFLG 0x2d
+# define EFLG_EWARN 0x01
+# define EFLG_RXWAR 0x02
+# define EFLG_TXWAR 0x04
+# define EFLG_RXEP 0x08
+# define EFLG_TXEP 0x10
+# define EFLG_TXBO 0x20
+# define EFLG_RX0OVR 0x40
+# define EFLG_RX1OVR 0x80
+#define TXBCTRL(n) (((n) * 0x10) + 0x30 + TXBCTRL_OFF)
+# define TXBCTRL_ABTF 0x40
+# define TXBCTRL_MLOA 0x20
+# define TXBCTRL_TXERR 0x10
+# define TXBCTRL_TXREQ 0x08
+#define TXBSIDH(n) (((n) * 0x10) + 0x30 + TXBSIDH_OFF)
+# define SIDH_SHIFT 3
+#define TXBSIDL(n) (((n) * 0x10) + 0x30 + TXBSIDL_OFF)
+# define SIDL_SID_MASK 7
+# define SIDL_SID_SHIFT 5
+# define SIDL_EXIDE_SHIFT 3
+# define SIDL_EID_SHIFT 16
+# define SIDL_EID_MASK 3
+#define TXBEID8(n) (((n) * 0x10) + 0x30 + TXBEID8_OFF)
+#define TXBEID0(n) (((n) * 0x10) + 0x30 + TXBEID0_OFF)
+#define TXBDLC(n) (((n) * 0x10) + 0x30 + TXBDLC_OFF)
+# define DLC_RTR_SHIFT 6
+#define TXBCTRL_OFF 0
+#define TXBSIDH_OFF 1
+#define TXBSIDL_OFF 2
+#define TXBEID8_OFF 3
+#define TXBEID0_OFF 4
+#define TXBDLC_OFF 5
+#define TXBDAT_OFF 6
+#define RXBCTRL(n) (((n) * 0x10) + 0x60 + RXBCTRL_OFF)
+# define RXBCTRL_BUKT 0x04
+# define RXBCTRL_RXM0 0x20
+# define RXBCTRL_RXM1 0x40
+#define RXBSIDH(n) (((n) * 0x10) + 0x60 + RXBSIDH_OFF)
+# define RXBSIDH_SHIFT 3
+#define RXBSIDL(n) (((n) * 0x10) + 0x60 + RXBSIDL_OFF)
+# define RXBSIDL_IDE 0x08
+# define RXBSIDL_SRR 0x10
+# define RXBSIDL_EID 3
+# define RXBSIDL_SHIFT 5
+#define RXBEID8(n) (((n) * 0x10) + 0x60 + RXBEID8_OFF)
+#define RXBEID0(n) (((n) * 0x10) + 0x60 + RXBEID0_OFF)
+#define RXBDLC(n) (((n) * 0x10) + 0x60 + RXBDLC_OFF)
+# define RXBDLC_LEN_MASK 0x0f
+# define RXBDLC_RTR 0x40
+#define RXBCTRL_OFF 0
+#define RXBSIDH_OFF 1
+#define RXBSIDL_OFF 2
+#define RXBEID8_OFF 3
+#define RXBEID0_OFF 4
+#define RXBDLC_OFF 5
+#define RXBDAT_OFF 6
+#define RXFSID(n) ((n < 3) ? 0 : 4)
+#define RXFSIDH(n) ((n) * 4 + RXFSID(n))
+#define RXFSIDL(n) ((n) * 4 + 1 + RXFSID(n))
+#define RXFEID8(n) ((n) * 4 + 2 + RXFSID(n))
+#define RXFEID0(n) ((n) * 4 + 3 + RXFSID(n))
+#define RXMSIDH(n) ((n) * 4 + 0x20)
+#define RXMSIDL(n) ((n) * 4 + 0x21)
+#define RXMEID8(n) ((n) * 4 + 0x22)
+#define RXMEID0(n) ((n) * 4 + 0x23)
+
+#define GET_BYTE(val, byte) \
+ (((val) >> ((byte) * 8)) & 0xff)
+#define SET_BYTE(val, byte) \
+ (((val) & 0xff) << ((byte) * 8))
+
+/*
+ * Buffer size required for the largest SPI transfer (i.e., reading a
+ * frame)
+ */
+#define CAN_FRAME_MAX_DATA_LEN 8
+#define SPI_TRANSFER_BUF_LEN (6 + CAN_FRAME_MAX_DATA_LEN)
+#define CAN_FRAME_MAX_BITS 128
+
+#define TX_ECHO_SKB_MAX 1
+
+#define MCP251X_OST_DELAY_MS (5)
+
+#define DEVICE_NAME "mcp251x"
+
+static int mcp251x_enable_dma; /* Enable SPI DMA. Default: 0 (Off) */
+module_param(mcp251x_enable_dma, int, 0444);
+MODULE_PARM_DESC(mcp251x_enable_dma, "Enable SPI DMA. Default: 0 (Off)");
+
+static const struct can_bittiming_const mcp251x_bittiming_const = {
+ .name = DEVICE_NAME,
+ .tseg1_min = 3,
+ .tseg1_max = 16,
+ .tseg2_min = 2,
+ .tseg2_max = 8,
+ .sjw_max = 4,
+ .brp_min = 1,
+ .brp_max = 64,
+ .brp_inc = 1,
+};
+
+enum mcp251x_model {
+ CAN_MCP251X_MCP2510 = 0x2510,
+ CAN_MCP251X_MCP2515 = 0x2515,
+};
+
+struct mcp251x_priv {
+ struct can_priv can;
+ struct net_device *net;
+ struct spi_device *spi;
+ enum mcp251x_model model;
+
+ struct mutex mcp_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 AFTER_SUSPEND_UP 1
+#define AFTER_SUSPEND_DOWN 2
+#define AFTER_SUSPEND_POWER 4
+#define AFTER_SUSPEND_RESTART 8
+ int restart_tx;
+ struct regulator *power;
+ struct regulator *transceiver;
+ struct clk *clk;
+};
+
+#define MCP251X_IS(_model) \
+static inline int mcp251x_is_##_model(struct spi_device *spi) \
+{ \
+ struct mcp251x_priv *priv = spi_get_drvdata(spi); \
+ return priv->model == CAN_MCP251X_MCP##_model; \
+}
+
+MCP251X_IS(2510);
+MCP251X_IS(2515);
+
+static void mcp251x_clean(struct net_device *net)
+{
+ struct mcp251x_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 mcp251x_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 mcp251x_spi_trans(struct spi_device *spi, int len)
+{
+ struct mcp251x_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 (mcp251x_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 u8 mcp251x_read_reg(struct spi_device *spi, uint8_t reg)
+{
+ struct mcp251x_priv *priv = spi_get_drvdata(spi);
+ u8 val = 0;
+
+ priv->spi_tx_buf[0] = INSTRUCTION_READ;
+ priv->spi_tx_buf[1] = reg;
+
+ mcp251x_spi_trans(spi, 3);
+ val = priv->spi_rx_buf[2];
+
+ return val;
+}
+
+static void mcp251x_read_2regs(struct spi_device *spi, uint8_t reg,
+ uint8_t *v1, uint8_t *v2)
+{
+ struct mcp251x_priv *priv = spi_get_drvdata(spi);
+
+ priv->spi_tx_buf[0] = INSTRUCTION_READ;
+ priv->spi_tx_buf[1] = reg;
+
+ mcp251x_spi_trans(spi, 4);
+
+ *v1 = priv->spi_rx_buf[2];
+ *v2 = priv->spi_rx_buf[3];
+}
+
+static void mcp251x_write_reg(struct spi_device *spi, u8 reg, uint8_t val)
+{
+ struct mcp251x_priv *priv = spi_get_drvdata(spi);
+
+ priv->spi_tx_buf[0] = INSTRUCTION_WRITE;
+ priv->spi_tx_buf[1] = reg;
+ priv->spi_tx_buf[2] = val;
+
+ mcp251x_spi_trans(spi, 3);
+}
+
+static void mcp251x_write_bits(struct spi_device *spi, u8 reg,
+ u8 mask, uint8_t val)
+{
+ struct mcp251x_priv *priv = spi_get_drvdata(spi);
+
+ priv->spi_tx_buf[0] = INSTRUCTION_BIT_MODIFY;
+ priv->spi_tx_buf[1] = reg;
+ priv->spi_tx_buf[2] = mask;
+ priv->spi_tx_buf[3] = val;
+
+ mcp251x_spi_trans(spi, 4);
+}
+
+static void mcp251x_hw_tx_frame(struct spi_device *spi, u8 *buf,
+ int len, int tx_buf_idx)
+{
+ struct mcp251x_priv *priv = spi_get_drvdata(spi);
+
+ if (mcp251x_is_2510(spi)) {
+ int i;
+
+ for (i = 1; i < TXBDAT_OFF + len; i++)
+ mcp251x_write_reg(spi, TXBCTRL(tx_buf_idx) + i,
+ buf[i]);
+ } else {
+ memcpy(priv->spi_tx_buf, buf, TXBDAT_OFF + len);
+ mcp251x_spi_trans(spi, TXBDAT_OFF + len);
+ }
+}
+
+static void mcp251x_hw_tx(struct spi_device *spi, struct can_frame *frame,
+ int tx_buf_idx)
+{
+ struct mcp251x_priv *priv = spi_get_drvdata(spi);
+ u32 sid, eid, exide, rtr;
+ u8 buf[SPI_TRANSFER_BUF_LEN];
+
+ exide = (frame->can_id & CAN_EFF_FLAG) ? 1 : 0; /* Extended ID Enable */
+ if (exide)
+ sid = (frame->can_id & CAN_EFF_MASK) >> 18;
+ else
+ sid = frame->can_id & CAN_SFF_MASK; /* Standard ID */
+ eid = frame->can_id & CAN_EFF_MASK; /* Extended ID */
+ rtr = (frame->can_id & CAN_RTR_FLAG) ? 1 : 0; /* Remote transmission */
+
+ buf[TXBCTRL_OFF] = INSTRUCTION_LOAD_TXB(tx_buf_idx);
+ buf[TXBSIDH_OFF] = sid >> SIDH_SHIFT;
+ buf[TXBSIDL_OFF] = ((sid & SIDL_SID_MASK) << SIDL_SID_SHIFT) |
+ (exide << SIDL_EXIDE_SHIFT) |
+ ((eid >> SIDL_EID_SHIFT) & SIDL_EID_MASK);
+ buf[TXBEID8_OFF] = GET_BYTE(eid, 1);
+ buf[TXBEID0_OFF] = GET_BYTE(eid, 0);
+ buf[TXBDLC_OFF] = (rtr << DLC_RTR_SHIFT) | frame->can_dlc;
+ memcpy(buf + TXBDAT_OFF, frame->data, frame->can_dlc);
+ mcp251x_hw_tx_frame(spi, buf, frame->can_dlc, tx_buf_idx);
+
+ /* use INSTRUCTION_RTS, to avoid "repeated frame problem" */
+ priv->spi_tx_buf[0] = INSTRUCTION_RTS(1 << tx_buf_idx);
+ mcp251x_spi_trans(priv->spi, 1);
+}
+
+static void mcp251x_hw_rx_frame(struct spi_device *spi, u8 *buf,
+ int buf_idx)
+{
+ struct mcp251x_priv *priv = spi_get_drvdata(spi);
+
+ if (mcp251x_is_2510(spi)) {
+ int i, len;
+
+ for (i = 1; i < RXBDAT_OFF; i++)
+ buf[i] = mcp251x_read_reg(spi, RXBCTRL(buf_idx) + i);
+
+ len = get_can_dlc(buf[RXBDLC_OFF] & RXBDLC_LEN_MASK);
+ for (; i < (RXBDAT_OFF + len); i++)
+ buf[i] = mcp251x_read_reg(spi, RXBCTRL(buf_idx) + i);
+ } else {
+ priv->spi_tx_buf[RXBCTRL_OFF] = INSTRUCTION_READ_RXB(buf_idx);
+ mcp251x_spi_trans(spi, SPI_TRANSFER_BUF_LEN);
+ memcpy(buf, priv->spi_rx_buf, SPI_TRANSFER_BUF_LEN);
+ }
+}
+
+static void mcp251x_hw_rx(struct spi_device *spi, int buf_idx)
+{
+ struct mcp251x_priv *priv = spi_get_drvdata(spi);
+ struct sk_buff *skb;
+ struct can_frame *frame;
+ u8 buf[SPI_TRANSFER_BUF_LEN];
+
+ skb = alloc_can_skb(priv->net, &frame);
+ if (!skb) {
+ dev_err(&spi->dev, "cannot allocate RX skb\n");
+ priv->net->stats.rx_dropped++;
+ return;
+ }
+
+ mcp251x_hw_rx_frame(spi, buf, buf_idx);
+ if (buf[RXBSIDL_OFF] & RXBSIDL_IDE) {
+ /* Extended ID format */
+ frame->can_id = CAN_EFF_FLAG;
+ frame->can_id |=
+ /* Extended ID part */
+ SET_BYTE(buf[RXBSIDL_OFF] & RXBSIDL_EID, 2) |
+ SET_BYTE(buf[RXBEID8_OFF], 1) |
+ SET_BYTE(buf[RXBEID0_OFF], 0) |
+ /* Standard ID part */
+ (((buf[RXBSIDH_OFF] << RXBSIDH_SHIFT) |
+ (buf[RXBSIDL_OFF] >> RXBSIDL_SHIFT)) << 18);
+ /* Remote transmission request */
+ if (buf[RXBDLC_OFF] & RXBDLC_RTR)
+ frame->can_id |= CAN_RTR_FLAG;
+ } else {
+ /* Standard ID format */
+ frame->can_id =
+ (buf[RXBSIDH_OFF] << RXBSIDH_SHIFT) |
+ (buf[RXBSIDL_OFF] >> RXBSIDL_SHIFT);
+ if (buf[RXBSIDL_OFF] & RXBSIDL_SRR)
+ frame->can_id |= CAN_RTR_FLAG;
+ }
+ /* Data length */
+ frame->can_dlc = get_can_dlc(buf[RXBDLC_OFF] & RXBDLC_LEN_MASK);
+ memcpy(frame->data, buf + RXBDAT_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 mcp251x_hw_sleep(struct spi_device *spi)
+{
+ mcp251x_write_reg(spi, CANCTRL, CANCTRL_REQOP_SLEEP);
+}
+
+static netdev_tx_t mcp251x_hard_start_xmit(struct sk_buff *skb,
+ struct net_device *net)
+{
+ struct mcp251x_priv *priv = netdev_priv(net);
+ struct spi_device *spi = priv->spi;
+
+ if (priv->tx_skb || priv->tx_len) {
+ dev_warn(&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 mcp251x_do_set_mode(struct net_device *net, enum can_mode mode)
+{
+ struct mcp251x_priv *priv = netdev_priv(net);
+
+ switch (mode) {
+ case CAN_MODE_START:
+ mcp251x_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 = AFTER_SUSPEND_RESTART;
+ queue_work(priv->wq, &priv->restart_work);
+ break;
+ default:
+ return -EOPNOTSUPP;
+ }
+
+ return 0;
+}
+
+static int mcp251x_set_normal_mode(struct spi_device *spi)
+{
+ struct mcp251x_priv *priv = spi_get_drvdata(spi);
+ unsigned long timeout;
+
+ /* Enable interrupts */
+ mcp251x_write_reg(spi, CANINTE,
+ CANINTE_ERRIE | CANINTE_TX2IE | CANINTE_TX1IE |
+ CANINTE_TX0IE | CANINTE_RX1IE | CANINTE_RX0IE);
+
+ if (priv->can.ctrlmode & CAN_CTRLMODE_LOOPBACK) {
+ /* Put device into loopback mode */
+ mcp251x_write_reg(spi, CANCTRL, CANCTRL_REQOP_LOOPBACK);
+ } else if (priv->can.ctrlmode & CAN_CTRLMODE_LISTENONLY) {
+ /* Put device into listen-only mode */
+ mcp251x_write_reg(spi, CANCTRL, CANCTRL_REQOP_LISTEN_ONLY);
+ } else {
+ /* Put device into normal mode */
+ mcp251x_write_reg(spi, CANCTRL, CANCTRL_REQOP_NORMAL);
+
+ /* Wait for the device to enter normal mode */
+ timeout = jiffies + HZ;
+ while (mcp251x_read_reg(spi, CANSTAT) & CANCTRL_REQOP_MASK) {
+ schedule();
+ if (time_after(jiffies, timeout)) {
+ dev_err(&spi->dev, "MCP251x didn't"
+ " enter in normal mode\n");
+ return -EBUSY;
+ }
+ }
+ }
+ priv->can.state = CAN_STATE_ERROR_ACTIVE;
+ return 0;
+}
+
+static int mcp251x_do_set_bittiming(struct net_device *net)
+{
+ struct mcp251x_priv *priv = netdev_priv(net);
+ struct can_bittiming *bt = &priv->can.bittiming;
+ struct spi_device *spi = priv->spi;
+
+ mcp251x_write_reg(spi, CNF1, ((bt->sjw - 1) << CNF1_SJW_SHIFT) |
+ (bt->brp - 1));
+ mcp251x_write_reg(spi, CNF2, CNF2_BTLMODE |
+ (priv->can.ctrlmode & CAN_CTRLMODE_3_SAMPLES ?
+ CNF2_SAM : 0) |
+ ((bt->phase_seg1 - 1) << CNF2_PS1_SHIFT) |
+ (bt->prop_seg - 1));
+ mcp251x_write_bits(spi, CNF3, CNF3_PHSEG2_MASK,
+ (bt->phase_seg2 - 1));
+ dev_dbg(&spi->dev, "CNF: 0x%02x 0x%02x 0x%02x\n",
+ mcp251x_read_reg(spi, CNF1),
+ mcp251x_read_reg(spi, CNF2),
+ mcp251x_read_reg(spi, CNF3));
+
+ return 0;
+}
+
+static int mcp251x_setup(struct net_device *net, struct spi_device *spi)
+{
+ mcp251x_do_set_bittiming(net);
+
+ mcp251x_write_reg(spi, RXBCTRL(0),
+ RXBCTRL_BUKT | RXBCTRL_RXM0 | RXBCTRL_RXM1);
+ mcp251x_write_reg(spi, RXBCTRL(1),
+ RXBCTRL_RXM0 | RXBCTRL_RXM1);
+ return 0;
+}
+
+static int mcp251x_hw_reset(struct spi_device *spi)
+{
+ struct mcp251x_priv *priv = spi_get_drvdata(spi);
+ u8 reg;
+ int ret;
+
+ /* Wait for oscillator startup timer after power up */
+ mdelay(MCP251X_OST_DELAY_MS);
+
+ priv->spi_tx_buf[0] = INSTRUCTION_RESET;
+ ret = mcp251x_spi_trans(spi, 1);
+ if (ret)
+ return ret;
+
+ /* Wait for oscillator startup timer after reset */
+ mdelay(MCP251X_OST_DELAY_MS);
+
+ reg = mcp251x_read_reg(spi, CANSTAT);
+ if ((reg & CANCTRL_REQOP_MASK) != CANCTRL_REQOP_CONF)
+ return -ENODEV;
+
+ return 0;
+}
+
+static int mcp251x_hw_probe(struct spi_device *spi)
+{
+ u8 ctrl;
+ int ret;
+
+ ret = mcp251x_hw_reset(spi);
+ if (ret)
+ return ret;
+
+ ctrl = mcp251x_read_reg(spi, CANCTRL);
+
+ dev_dbg(&spi->dev, "CANCTRL 0x%02x\n", ctrl);
+
+ /* Check for power up default value */
+ if ((ctrl & 0x17) != 0x07)
+ return -ENODEV;
+
+ return 0;
+}
+
+static int mcp251x_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 void mcp251x_open_clean(struct net_device *net)
+{
+ struct mcp251x_priv *priv = netdev_priv(net);
+ struct spi_device *spi = priv->spi;
+
+ free_irq(spi->irq, priv);
+ mcp251x_hw_sleep(spi);
+ mcp251x_power_enable(priv->transceiver, 0);
+ close_candev(net);
+}
+
+static int mcp251x_stop(struct net_device *net)
+{
+ struct mcp251x_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->mcp_lock);
+
+ /* Disable and clear pending interrupts */
+ mcp251x_write_reg(spi, CANINTE, 0x00);
+ mcp251x_write_reg(spi, CANINTF, 0x00);
+
+ mcp251x_write_reg(spi, TXBCTRL(0), 0);
+ mcp251x_clean(net);
+
+ mcp251x_hw_sleep(spi);
+
+ mcp251x_power_enable(priv->transceiver, 0);
+
+ priv->can.state = CAN_STATE_STOPPED;
+
+ mutex_unlock(&priv->mcp_lock);
+
+ can_led_event(net, CAN_LED_EVENT_STOP);
+
+ return 0;
+}
+
+static void mcp251x_error_skb(struct net_device *net, int can_id, int data1)
+{
+ struct sk_buff *skb;
+ struct can_frame *frame;
+
+ skb = alloc_can_err_skb(net, &frame);
+ if (skb) {
+ frame->can_id |= can_id;
+ frame->data[1] = data1;
+ netif_rx_ni(skb);
+ } else {
+ netdev_err(net, "cannot allocate error skb\n");
+ }
+}
+
+static void mcp251x_tx_work_handler(struct work_struct *ws)
+{
+ struct mcp251x_priv *priv = container_of(ws, struct mcp251x_priv,
+ tx_work);
+ struct spi_device *spi = priv->spi;
+ struct net_device *net = priv->net;
+ struct can_frame *frame;
+
+ mutex_lock(&priv->mcp_lock);
+ if (priv->tx_skb) {
+ if (priv->can.state == CAN_STATE_BUS_OFF) {
+ mcp251x_clean(net);
+ } else {
+ frame = (struct can_frame *)priv->tx_skb->data;
+
+ if (frame->can_dlc > CAN_FRAME_MAX_DATA_LEN)
+ frame->can_dlc = CAN_FRAME_MAX_DATA_LEN;
+ mcp251x_hw_tx(spi, frame, 0);
+ priv->tx_len = 1 + frame->can_dlc;
+ can_put_echo_skb(priv->tx_skb, net, 0);
+ priv->tx_skb = NULL;
+ }
+ }
+ mutex_unlock(&priv->mcp_lock);
+}
+
+static void mcp251x_restart_work_handler(struct work_struct *ws)
+{
+ struct mcp251x_priv *priv = container_of(ws, struct mcp251x_priv,
+ restart_work);
+ struct spi_device *spi = priv->spi;
+ struct net_device *net = priv->net;
+
+ mutex_lock(&priv->mcp_lock);
+ if (priv->after_suspend) {
+ mcp251x_hw_reset(spi);
+ mcp251x_setup(net, spi);
+ if (priv->after_suspend & AFTER_SUSPEND_RESTART) {
+ mcp251x_set_normal_mode(spi);
+ } else if (priv->after_suspend & AFTER_SUSPEND_UP) {
+ netif_device_attach(net);
+ mcp251x_clean(net);
+ mcp251x_set_normal_mode(spi);
+ netif_wake_queue(net);
+ } else {
+ mcp251x_hw_sleep(spi);
+ }
+ priv->after_suspend = 0;
+ priv->force_quit = 0;
+ }
+
+ if (priv->restart_tx) {
+ priv->restart_tx = 0;
+ mcp251x_write_reg(spi, TXBCTRL(0), 0);
+ mcp251x_clean(net);
+ netif_wake_queue(net);
+ mcp251x_error_skb(net, CAN_ERR_RESTARTED, 0);
+ }
+ mutex_unlock(&priv->mcp_lock);
+}
+
+static irqreturn_t mcp251x_can_ist(int irq, void *dev_id)
+{
+ struct mcp251x_priv *priv = dev_id;
+ struct spi_device *spi = priv->spi;
+ struct net_device *net = priv->net;
+
+ mutex_lock(&priv->mcp_lock);
+ while (!priv->force_quit) {
+ enum can_state new_state;
+ u8 intf, eflag;
+ u8 clear_intf = 0;
+ int can_id = 0, data1 = 0;
+
+ mcp251x_read_2regs(spi, CANINTF, &intf, &eflag);
+
+ /* mask out flags we don't care about */
+ intf &= CANINTF_RX | CANINTF_TX | CANINTF_ERR;
+
+ /* receive buffer 0 */
+ if (intf & CANINTF_RX0IF) {
+ mcp251x_hw_rx(spi, 0);
+ /*
+ * Free one buffer ASAP
+ * (The MCP2515 does this automatically.)
+ */
+ if (mcp251x_is_2510(spi))
+ mcp251x_write_bits(spi, CANINTF, CANINTF_RX0IF, 0x00);
+ }
+
+ /* receive buffer 1 */
+ if (intf & CANINTF_RX1IF) {
+ mcp251x_hw_rx(spi, 1);
+ /* the MCP2515 does this automatically */
+ if (mcp251x_is_2510(spi))
+ clear_intf |= CANINTF_RX1IF;
+ }
+
+ /* any error or tx interrupt we need to clear? */
+ if (intf & (CANINTF_ERR | CANINTF_TX))
+ clear_intf |= intf & (CANINTF_ERR | CANINTF_TX);
+ if (clear_intf)
+ mcp251x_write_bits(spi, CANINTF, clear_intf, 0x00);
+
+ if (eflag & (EFLG_RX0OVR | EFLG_RX1OVR))
+ mcp251x_write_bits(spi, EFLG, eflag, 0x00);
+
+ /* Update can state */
+ if (eflag & EFLG_TXBO) {
+ new_state = CAN_STATE_BUS_OFF;
+ can_id |= CAN_ERR_BUSOFF;
+ } else if (eflag & EFLG_TXEP) {
+ new_state = CAN_STATE_ERROR_PASSIVE;
+ can_id |= CAN_ERR_CRTL;
+ data1 |= CAN_ERR_CRTL_TX_PASSIVE;
+ } else if (eflag & EFLG_RXEP) {
+ new_state = CAN_STATE_ERROR_PASSIVE;
+ can_id |= CAN_ERR_CRTL;
+ data1 |= CAN_ERR_CRTL_RX_PASSIVE;
+ } else if (eflag & EFLG_TXWAR) {
+ new_state = CAN_STATE_ERROR_WARNING;
+ can_id |= CAN_ERR_CRTL;
+ data1 |= CAN_ERR_CRTL_TX_WARNING;
+ } else if (eflag & EFLG_RXWAR) {
+ new_state = CAN_STATE_ERROR_WARNING;
+ can_id |= CAN_ERR_CRTL;
+ data1 |= CAN_ERR_CRTL_RX_WARNING;
+ } else {
+ new_state = CAN_STATE_ERROR_ACTIVE;
+ }
+
+ /* Update can state statistics */
+ switch (priv->can.state) {
+ case CAN_STATE_ERROR_ACTIVE:
+ if (new_state >= CAN_STATE_ERROR_WARNING &&
+ new_state <= CAN_STATE_BUS_OFF)
+ priv->can.can_stats.error_warning++;
+ case CAN_STATE_ERROR_WARNING: /* fallthrough */
+ if (new_state >= CAN_STATE_ERROR_PASSIVE &&
+ new_state <= CAN_STATE_BUS_OFF)
+ priv->can.can_stats.error_passive++;
+ break;
+ default:
+ break;
+ }
+ priv->can.state = new_state;
+
+ if (intf & CANINTF_ERRIF) {
+ /* Handle overflow counters */
+ if (eflag & (EFLG_RX0OVR | EFLG_RX1OVR)) {
+ if (eflag & EFLG_RX0OVR) {
+ net->stats.rx_over_errors++;
+ net->stats.rx_errors++;
+ }
+ if (eflag & EFLG_RX1OVR) {
+ net->stats.rx_over_errors++;
+ net->stats.rx_errors++;
+ }
+ can_id |= CAN_ERR_CRTL;
+ data1 |= CAN_ERR_CRTL_RX_OVERFLOW;
+ }
+ mcp251x_error_skb(net, can_id, data1);
+ }
+
+ if (priv->can.state == CAN_STATE_BUS_OFF) {
+ if (priv->can.restart_ms == 0) {
+ priv->force_quit = 1;
+ priv->can.can_stats.bus_off++;
+ can_bus_off(net);
+ mcp251x_hw_sleep(spi);
+ break;
+ }
+ }
+
+ if (intf == 0)
+ break;
+
+ if (intf & CANINTF_TX) {
+ 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);
+ }
+
+ }
+ mutex_unlock(&priv->mcp_lock);
+ return IRQ_HANDLED;
+}
+
+static int mcp251x_open(struct net_device *net)
+{
+ struct mcp251x_priv *priv = netdev_priv(net);
+ struct spi_device *spi = priv->spi;
+ unsigned long flags = IRQF_ONESHOT | IRQF_TRIGGER_FALLING;
+ int ret;
+
+ ret = open_candev(net);
+ if (ret) {
+ dev_err(&spi->dev, "unable to set initial baudrate!\n");
+ return ret;
+ }
+
+ mutex_lock(&priv->mcp_lock);
+ mcp251x_power_enable(priv->transceiver, 1);
+
+ priv->force_quit = 0;
+ priv->tx_skb = NULL;
+ priv->tx_len = 0;
+
+ ret = request_threaded_irq(spi->irq, NULL, mcp251x_can_ist,
+ flags | IRQF_ONESHOT, DEVICE_NAME, priv);
+ if (ret) {
+ dev_err(&spi->dev, "failed to acquire irq %d\n", spi->irq);
+ mcp251x_power_enable(priv->transceiver, 0);
+ close_candev(net);
+ goto open_unlock;
+ }
+
+ priv->wq = alloc_workqueue("mcp251x_wq", WQ_FREEZABLE | WQ_MEM_RECLAIM,
+ 0);
+ INIT_WORK(&priv->tx_work, mcp251x_tx_work_handler);
+ INIT_WORK(&priv->restart_work, mcp251x_restart_work_handler);
+
+ ret = mcp251x_hw_reset(spi);
+ if (ret) {
+ mcp251x_open_clean(net);
+ goto open_unlock;
+ }
+ ret = mcp251x_setup(net, spi);
+ if (ret) {
+ mcp251x_open_clean(net);
+ goto open_unlock;
+ }
+ ret = mcp251x_set_normal_mode(spi);
+ if (ret) {
+ mcp251x_open_clean(net);
+ goto open_unlock;
+ }
+
+ can_led_event(net, CAN_LED_EVENT_OPEN);
+
+ netif_wake_queue(net);
+
+open_unlock:
+ mutex_unlock(&priv->mcp_lock);
+ return ret;
+}
+
+static const struct net_device_ops mcp251x_netdev_ops = {
+ .ndo_open = mcp251x_open,
+ .ndo_stop = mcp251x_stop,
+ .ndo_start_xmit = mcp251x_hard_start_xmit,
+ .ndo_change_mtu = can_change_mtu,
+};
+
+static const struct of_device_id mcp251x_of_match[] = {
+ {
+ .compatible = "microchip,mcp2510",
+ .data = (void *)CAN_MCP251X_MCP2510,
+ },
+ {
+ .compatible = "microchip,mcp2515",
+ .data = (void *)CAN_MCP251X_MCP2515,
+ },
+ { }
+};
+MODULE_DEVICE_TABLE(of, mcp251x_of_match);
+
+static const struct spi_device_id mcp251x_id_table[] = {
+ {
+ .name = "mcp2510",
+ .driver_data = (kernel_ulong_t)CAN_MCP251X_MCP2510,
+ },
+ {
+ .name = "mcp2515",
+ .driver_data = (kernel_ulong_t)CAN_MCP251X_MCP2515,
+ },
+ { }
+};
+MODULE_DEVICE_TABLE(spi, mcp251x_id_table);
+
+static int mcp251x_can_probe(struct spi_device *spi)
+{
+ const struct of_device_id *of_id = of_match_device(mcp251x_of_match,
+ &spi->dev);
+ struct mcp251x_platform_data *pdata = dev_get_platdata(&spi->dev);
+ struct net_device *net;
+ struct mcp251x_priv *priv;
+ struct clk *clk;
+ int freq, ret;
+
+ clk = devm_clk_get(&spi->dev, NULL);
+ if (IS_ERR(clk)) {
+ if (pdata)
+ freq = pdata->oscillator_frequency;
+ else
+ return PTR_ERR(clk);
+ } else {
+ freq = clk_get_rate(clk);
+ }
+
+ /* Sanity check */
+ if (freq < 1000000 || freq > 25000000)
+ return -ERANGE;
+
+ /* Allocate can/net device */
+ net = alloc_candev(sizeof(struct mcp251x_priv), 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 = &mcp251x_netdev_ops;
+ net->flags |= IFF_ECHO;
+
+ priv = netdev_priv(net);
+ priv->can.bittiming_const = &mcp251x_bittiming_const;
+ priv->can.do_set_mode = mcp251x_do_set_mode;
+ priv->can.clock.freq = freq / 2;
+ priv->can.ctrlmode_supported = CAN_CTRLMODE_3_SAMPLES |
+ CAN_CTRLMODE_LOOPBACK | CAN_CTRLMODE_LISTENONLY;
+ if (of_id)
+ priv->model = (enum mcp251x_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;
+ if (mcp251x_is_2510(spi))
+ spi->max_speed_hz = spi->max_speed_hz ? : 5 * 1000 * 1000;
+ else
+ spi->max_speed_hz = spi->max_speed_hz ? : 10 * 1000 * 1000;
+ 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 = mcp251x_power_enable(priv->power, 1);
+ if (ret)
+ goto out_clk;
+
+ priv->spi = spi;
+ mutex_init(&priv->mcp_lock);
+
+ /* If requested, allocate DMA buffers */
+ if (mcp251x_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 */
+ mcp251x_enable_dma = 0;
+ }
+ }
+
+ /* Allocate non-DMA buffers */
+ if (!mcp251x_enable_dma) {
+ priv->spi_tx_buf = devm_kzalloc(&spi->dev, SPI_TRANSFER_BUF_LEN,
+ GFP_KERNEL);
+ if (!priv->spi_tx_buf) {
+ ret = -ENOMEM;
+ goto error_probe;
+ }
+ priv->spi_rx_buf = devm_kzalloc(&spi->dev, SPI_TRANSFER_BUF_LEN,
+ GFP_KERNEL);
+ if (!priv->spi_rx_buf) {
+ ret = -ENOMEM;
+ goto error_probe;
+ }
+ }
+
+ SET_NETDEV_DEV(net, &spi->dev);
+
+ /* Here is OK to not lock the MCP, no one knows about it yet */
+ ret = mcp251x_hw_probe(spi);
+ if (ret) {
+ if (ret == -ENODEV)
+ dev_err(&spi->dev, "Cannot initialize MCP%x. Wrong wiring?\n", priv->model);
+ goto error_probe;
+ }
+
+ mcp251x_hw_sleep(spi);
+
+ ret = register_candev(net);
+ if (ret)
+ goto error_probe;
+
+ devm_can_led_init(net);
+
+ netdev_info(net, "MCP%x successfully initialized.\n", priv->model);
+ return 0;
+
+error_probe:
+ mcp251x_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 mcp251x_can_remove(struct spi_device *spi)
+{
+ struct mcp251x_priv *priv = spi_get_drvdata(spi);
+ struct net_device *net = priv->net;
+
+ unregister_candev(net);
+
+ mcp251x_power_enable(priv->power, 0);
+
+ if (!IS_ERR(priv->clk))
+ clk_disable_unprepare(priv->clk);
+
+ free_candev(net);
+
+ return 0;
+}
+
+static int __maybe_unused mcp251x_can_suspend(struct device *dev)
+{
+ struct spi_device *spi = to_spi_device(dev);
+ struct mcp251x_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);
+
+ mcp251x_hw_sleep(spi);
+ mcp251x_power_enable(priv->transceiver, 0);
+ priv->after_suspend = AFTER_SUSPEND_UP;
+ } else {
+ priv->after_suspend = AFTER_SUSPEND_DOWN;
+ }
+
+ if (!IS_ERR_OR_NULL(priv->power)) {
+ regulator_disable(priv->power);
+ priv->after_suspend |= AFTER_SUSPEND_POWER;
+ }
+
+ return 0;
+}
+
+static int __maybe_unused mcp251x_can_resume(struct device *dev)
+{
+ struct spi_device *spi = to_spi_device(dev);
+ struct mcp251x_priv *priv = spi_get_drvdata(spi);
+
+ if (priv->after_suspend & AFTER_SUSPEND_POWER)
+ mcp251x_power_enable(priv->power, 1);
+
+ if (priv->after_suspend & AFTER_SUSPEND_UP) {
+ mcp251x_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(mcp251x_can_pm_ops, mcp251x_can_suspend,
+ mcp251x_can_resume);
+
+static struct spi_driver mcp251x_can_driver = {
+ .driver = {
+ .name = DEVICE_NAME,
+ .of_match_table = mcp251x_of_match,
+ .pm = &mcp251x_can_pm_ops,
+ },
+ .id_table = mcp251x_id_table,
+ .probe = mcp251x_can_probe,
+ .remove = mcp251x_can_remove,
+};
+module_spi_driver(mcp251x_can_driver);
+
+MODULE_AUTHOR("Chris Elston <celston@katalix.com>, "
+ "Christian Pellegrin <chripell@evolware.org>");
+MODULE_DESCRIPTION("Microchip 251x CAN driver");
+MODULE_LICENSE("GPL v2");