lkml.org 
[lkml]   [2010]   [Mar]   [2]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH 2/3] can: add support for Janz VMOD-ICAN3 Intelligent CAN module
Date
The Janz VMOD-ICAN3 is a MODULbus daughterboard which fits onto any
MODULbus carrier board. It is an intelligent CAN controller with a
microcontroller and associated firmware.

Signed-off-by: Ira W. Snyder <iws@ovro.caltech.edu>
Cc: socketcan-core@lists.berlios.de
---
drivers/net/can/Kconfig | 10 +
drivers/net/can/Makefile | 1 +
drivers/net/can/janz-ican3.c | 1659 ++++++++++++++++++++++++++++++++++++++++++
3 files changed, 1670 insertions(+), 0 deletions(-)
create mode 100644 drivers/net/can/janz-ican3.c
diff --git a/drivers/net/can/Kconfig b/drivers/net/can/Kconfig
index 05b7517..2c5227c 100644
--- a/drivers/net/can/Kconfig
+++ b/drivers/net/can/Kconfig
@@ -63,6 +63,16 @@ config CAN_BFIN
To compile this driver as a module, choose M here: the
module will be called bfin_can.

+config CAN_JANZ_ICAN3
+ tristate "Janz VMOD-ICAN3 Intelligent CAN controller"
+ depends on CAN_DEV && MFD_JANZ_CMODIO
+ ---help---
+ Driver for Janz VMOD-ICAN3 Intelligent CAN controller module, which
+ connects to a MODULbus carrier board.
+
+ This driver can also be built as a module. If so, the module will be
+ called janz-ican3.ko.
+
source "drivers/net/can/mscan/Kconfig"

source "drivers/net/can/sja1000/Kconfig"
diff --git a/drivers/net/can/Makefile b/drivers/net/can/Makefile
index 7a702f2..9047cd0 100644
--- a/drivers/net/can/Makefile
+++ b/drivers/net/can/Makefile
@@ -15,5 +15,6 @@ obj-$(CONFIG_CAN_AT91) += at91_can.o
obj-$(CONFIG_CAN_TI_HECC) += ti_hecc.o
obj-$(CONFIG_CAN_MCP251X) += mcp251x.o
obj-$(CONFIG_CAN_BFIN) += bfin_can.o
+obj-$(CONFIG_CAN_JANZ_ICAN3) += janz-ican3.o

ccflags-$(CONFIG_CAN_DEBUG_DEVICES) := -DDEBUG
diff --git a/drivers/net/can/janz-ican3.c b/drivers/net/can/janz-ican3.c
new file mode 100644
index 0000000..94d4995
--- /dev/null
+++ b/drivers/net/can/janz-ican3.c
@@ -0,0 +1,1659 @@
+/*
+ * Janz MODULbus VMOD-ICAN3 CAN Interface Driver
+ *
+ * Copyright (c) 2010 Ira W. Snyder <iws@ovro.caltech.edu>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2 of the License, or (at your
+ * option) any later version.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/delay.h>
+#include <linux/platform_device.h>
+
+#include <linux/netdevice.h>
+#include <linux/can.h>
+#include <linux/can/dev.h>
+#include <linux/can/error.h>
+
+#include <linux/mfd/janz.h>
+
+/* the DPM has 64k of memory, organized into 256x 256 byte pages */
+#define DPM_NUM_PAGES 256
+#define DPM_PAGE_SIZE 256
+#define DPM_PAGE_ADDR(p) ((p) * DPM_PAGE_SIZE)
+
+/* JANZ ICAN3 "old-style" host interface queue page numbers */
+#define QUEUE_OLD_CONTROL 0
+#define QUEUE_OLD_RB0 1
+#define QUEUE_OLD_RB1 2
+#define QUEUE_OLD_WB0 3
+#define QUEUE_OLD_WB1 4
+
+/* Janz ICAN3 "old-style" host interface control registers */
+#define MSYNC_PEER 0x00 /* ICAN only */
+#define MSYNC_LOCL 0x01 /* host only */
+#define TARGET_RUNNING 0x02
+
+#define MSYNC_RB0 0x01
+#define MSYNC_RB1 0x02
+#define MSYNC_RBLW 0x04
+#define MSYNC_RB_MASK (MSYNC_RB0 | MSYNC_RB1)
+
+#define MSYNC_WB0 0x10
+#define MSYNC_WB1 0x20
+#define MSYNC_WBLW 0x40
+#define MSYNC_WB_MASK (MSYNC_WB0 | MSYNC_WB1)
+
+/* Janz ICAN3 "new-style" host interface queue page numbers */
+#define QUEUE_TOHOST 5
+#define QUEUE_FROMHOST_MID 6
+#define QUEUE_FROMHOST_HIGH 7
+#define QUEUE_FROMHOST_LOW 8
+
+/* The first free page in the DPM is #9 */
+#define DPM_FREE_START 9
+
+/* Janz ICAN3 "new-style" and "fast" host interface descriptor flags */
+#define DESC_VALID 0x80
+#define DESC_WRAP 0x40
+#define DESC_INTERRUPT 0x20
+#define DESC_IVALID 0x10
+#define DESC_LEN(len) (len)
+
+/* Janz ICAN3 Firmware Messages */
+#define MSG_CONNECTI 0x02
+#define MSG_DISCONNECT 0x03
+#define MSG_IDVERS 0x04
+#define MSG_MSGLOST 0x05
+#define MSG_NEWHOSTIF 0x08
+#define MSG_SETAFILMASK 0x10
+#define MSG_INITFDPMQUEUE 0x11
+#define MSG_HWCONF 0x12
+#define MSG_FMSGLOST 0x15
+#define MSG_CEVTIND 0x37
+#define MSG_CBTRREQ 0x41
+#define MSG_COFFREQ 0x42
+#define MSG_CONREQ 0x43
+#define MSG_CCONFREQ 0x47
+
+/* Janz ICAN3 CAN Set Acceptance Filter Mask Message Types */
+#define SETAFILMASK_REJECT 0x00
+#define SETAFILMASK_FASTIF 0x02
+
+/* Janz ICAN3 CAN Hardware Configuration Message Types */
+#define HWCONF_TERMINATE_ON 0x01
+#define HWCONF_TERMINATE_OFF 0x00
+
+/* Janz ICAN3 CAN Event Indication Message Types */
+#define CEVTIND_EI 0x01
+#define CEVTIND_DOI 0x02
+#define CEVTIND_LOST 0x04
+#define CEVTIND_FULL 0x08
+#define CEVTIND_BEI 0x10
+
+#define CEVTIND_CHIP_SJA1000 0x02
+
+#define ICAN3_BUSERR_QUOTA_MAX 255
+
+/* Janz ICAN3 CAN Frame Conversion */
+#define ICAN3_ECHO 0x10
+#define ICAN3_EFF_RTR 0x40
+#define ICAN3_SFF_RTR 0x10
+#define ICAN3_EFF 0x80
+
+#define ICAN3_CAN_TYPE_MASK 0x0f
+#define ICAN3_CAN_TYPE_SFF 0x00
+#define ICAN3_CAN_TYPE_EFF 0x01
+
+#define ICAN3_CAN_DLC_MASK 0x0f
+
+/*
+ * SJA1000 Status and Error Register Definitions
+ *
+ * Copied from drivers/net/can/sja1000/sja1000.h
+ */
+
+/* status register content */
+#define SR_BS 0x80
+#define SR_ES 0x40
+#define SR_TS 0x20
+#define SR_RS 0x10
+#define SR_TCS 0x08
+#define SR_TBS 0x04
+#define SR_DOS 0x02
+#define SR_RBS 0x01
+
+#define SR_CRIT (SR_BS|SR_ES)
+
+/* ECC register */
+#define ECC_SEG 0x1F
+#define ECC_DIR 0x20
+#define ECC_ERR 6
+#define ECC_BIT 0x00
+#define ECC_FORM 0x40
+#define ECC_STUFF 0x80
+#define ECC_MASK 0xc0
+
+/* Number of buffers for use in the "new-style" host interface */
+#define ICAN3_NEW_BUFFERS 16
+
+/* Number of buffers for use in the "fast" host interface */
+#define ICAN3_TX_BUFFERS 512
+#define ICAN3_RX_BUFFERS 1024
+
+/* Driver Name */
+#define DRV_NAME "janz-ican3"
+
+/* DPM Control Registers -- starts at offset 0x100 in the MODULbus registers */
+struct ican3_dpm_control {
+ /* window address register */
+ u8 window_address;
+ u8 unused1;
+
+ /*
+ * Read access: clear interrupt from microcontroller
+ * Write access: send interrupt to microcontroller
+ */
+ u8 interrupt;
+ u8 unused2;
+
+ /* write-only: reset all hardware on the module */
+ u8 hwreset;
+ u8 unused3;
+
+ /* write-only: generate an interrupt to the TPU */
+ u8 tpuinterrupt;
+};
+
+struct ican3_dev {
+
+ /* must be the first member */
+ struct can_priv can;
+
+ /* CAN network device */
+ struct net_device *ndev;
+ struct napi_struct napi;
+
+ /* Device for printing */
+ struct device *dev;
+
+ /* module number */
+ unsigned int num;
+
+ /* base address of registers and IRQ */
+ struct janz_cmodio_onboard_regs __iomem *ctrl;
+ struct ican3_dpm_control *dpmctrl;
+ void __iomem *dpm;
+ int irq;
+
+ /* old and new style host interface */
+ unsigned int iftype;
+ spinlock_t lock;
+
+ /* new host interface */
+ unsigned int rx_int;
+ unsigned int rx_num;
+ unsigned int tx_num;
+
+ /* fast host interface */
+ unsigned int fastrx_start;
+ unsigned int fastrx_int;
+ unsigned int fastrx_num;
+ unsigned int fasttx_start;
+ unsigned int fasttx_num;
+
+ /* first free DPM page */
+ unsigned int free_page;
+};
+
+struct ican3_msg {
+ u8 control;
+ u8 spec;
+ __le16 len;
+ u8 data[252];
+};
+
+struct ican3_new_desc {
+ u8 control;
+ u8 pointer;
+};
+
+struct ican3_fast_desc {
+ u8 control;
+ u8 command;
+ u8 data[14];
+};
+
+/* write to the window basic address register */
+static inline void ican3_set_page(struct ican3_dev *mod, unsigned int page)
+{
+ BUG_ON(page >= DPM_NUM_PAGES);
+ iowrite8(page, &mod->dpmctrl->window_address);
+}
+
+/*
+ * ICAN3 "old-style" host interface
+ */
+
+/*
+ * Recieve a message from the ICAN3 "old-style" firmware interface
+ *
+ * LOCKING: must hold mod->lock
+ *
+ * returns 0 on success, -ENOMEM when no message exists
+ */
+static int ican3_old_recv_msg(struct ican3_dev *mod, struct ican3_msg *msg)
+{
+ unsigned int mbox, mbox_page;
+ u8 locl, peer, xord;
+
+ /* get the MSYNC registers */
+ ican3_set_page(mod, QUEUE_OLD_CONTROL);
+ peer = ioread8(mod->dpm + MSYNC_PEER);
+ locl = ioread8(mod->dpm + MSYNC_LOCL);
+ xord = locl ^ peer;
+
+ if ((xord & MSYNC_RB_MASK) == 0x00) {
+ dev_dbg(mod->dev, "no mbox for reading\n");
+ return -ENOMEM;
+ }
+
+ /* find the first free mbox to read */
+ if ((xord & MSYNC_RB_MASK) == MSYNC_RB_MASK)
+ mbox = (xord & MSYNC_RBLW) ? MSYNC_RB0 : MSYNC_RB1;
+ else
+ mbox = (xord & MSYNC_RB0) ? MSYNC_RB0 : MSYNC_RB1;
+
+ /* copy the message */
+ mbox_page = (mbox == MSYNC_RB0) ? QUEUE_OLD_RB0 : QUEUE_OLD_RB1;
+ ican3_set_page(mod, mbox_page);
+ memcpy_fromio(msg, mod->dpm, sizeof(*msg));
+
+ /*
+ * notify the firmware that the read buffer is available
+ * for it to fill again
+ */
+ locl ^= mbox;
+
+ ican3_set_page(mod, QUEUE_OLD_CONTROL);
+ iowrite8(locl, mod->dpm + MSYNC_LOCL);
+ return 0;
+}
+
+/*
+ * Send a message through the "old-style" firmware interface
+ *
+ * LOCKING: must hold mod->lock
+ *
+ * returns 0 on success, -ENOMEM when no free space exists
+ */
+static int ican3_old_send_msg(struct ican3_dev *mod, struct ican3_msg *msg)
+{
+ unsigned int mbox, mbox_page;
+ u8 locl, peer, xord;
+
+ /* get the MSYNC registers */
+ ican3_set_page(mod, QUEUE_OLD_CONTROL);
+ peer = ioread8(mod->dpm + MSYNC_PEER);
+ locl = ioread8(mod->dpm + MSYNC_LOCL);
+ xord = locl ^ peer;
+
+ if ((xord & MSYNC_WB_MASK) == MSYNC_WB_MASK) {
+ dev_err(mod->dev, "no mbox for writing\n");
+ return -ENOMEM;
+ }
+
+ /* calculate a free mbox to use */
+ mbox = (xord & MSYNC_WB0) ? MSYNC_WB1 : MSYNC_WB0;
+
+ /* copy the message to the DPM */
+ mbox_page = (mbox == MSYNC_WB0) ? QUEUE_OLD_WB0 : QUEUE_OLD_WB1;
+ ican3_set_page(mod, mbox_page);
+ memcpy_toio(mod->dpm, msg, sizeof(*msg));
+
+ locl ^= mbox;
+ if (mbox == MSYNC_WB1)
+ locl |= MSYNC_WBLW;
+
+ ican3_set_page(mod, QUEUE_OLD_CONTROL);
+ iowrite8(locl, mod->dpm + MSYNC_LOCL);
+ return 0;
+}
+
+/*
+ * ICAN3 "new-style" Host Interface Setup
+ */
+
+static void __devinit ican3_init_new_host_interface(struct ican3_dev *mod)
+{
+ struct ican3_new_desc desc;
+ unsigned long flags;
+ void __iomem *dst;
+ int i;
+
+ spin_lock_irqsave(&mod->lock, flags);
+
+ /* setup the internal datastructures for RX */
+ mod->rx_num = 0;
+ mod->rx_int = 0;
+
+ /* tohost queue descriptors are in page 5 */
+ ican3_set_page(mod, QUEUE_TOHOST);
+ dst = mod->dpm;
+
+ /* initialize the tohost (rx) queue descriptors: pages 9-24 */
+ for (i = 0; i < ICAN3_NEW_BUFFERS; i++) {
+ desc.control = DESC_INTERRUPT | DESC_LEN(1); /* I L=1 */
+ desc.pointer = mod->free_page;
+
+ /* set wrap flag on last buffer */
+ if (i == ICAN3_NEW_BUFFERS - 1)
+ desc.control |= DESC_WRAP;
+
+ memcpy_toio(dst, &desc, sizeof(desc));
+ dst += sizeof(desc);
+ mod->free_page++;
+ }
+
+ /* fromhost (tx) mid queue descriptors are in page 6 */
+ ican3_set_page(mod, QUEUE_FROMHOST_MID);
+ dst = mod->dpm;
+
+ /* setup the internal datastructures for TX */
+ mod->tx_num = 0;
+
+ /* initialize the fromhost mid queue descriptors: pages 25-40 */
+ for (i = 0; i < ICAN3_NEW_BUFFERS; i++) {
+ desc.control = DESC_VALID | DESC_LEN(1); /* V L=1 */
+ desc.pointer = mod->free_page;
+
+ /* set wrap flag on last buffer */
+ if (i == ICAN3_NEW_BUFFERS - 1)
+ desc.control |= DESC_WRAP;
+
+ memcpy_toio(dst, &desc, sizeof(desc));
+ dst += sizeof(desc);
+ mod->free_page++;
+ }
+
+ /* fromhost hi queue descriptors are in page 7 */
+ ican3_set_page(mod, QUEUE_FROMHOST_HIGH);
+ dst = mod->dpm;
+
+ /* initialize only a single buffer in the fromhost hi queue (unused) */
+ desc.control = DESC_VALID | DESC_WRAP | DESC_LEN(1); /* VW L=1 */
+ desc.pointer = mod->free_page;
+ memcpy_toio(dst, &desc, sizeof(desc));
+ mod->free_page++;
+
+ /* fromhost low queue descriptors are in page 8 */
+ ican3_set_page(mod, QUEUE_FROMHOST_LOW);
+ dst = mod->dpm;
+
+ /* initialize only a single buffer in the fromhost low queue (unused) */
+ desc.control = DESC_VALID | DESC_WRAP | DESC_LEN(1); /* VW L=1 */
+ desc.pointer = mod->free_page;
+ memcpy_toio(dst, &desc, sizeof(desc));
+ mod->free_page++;
+
+ spin_unlock_irqrestore(&mod->lock, flags);
+}
+
+/*
+ * ICAN3 Fast Host Interface Setup
+ */
+
+static void __devinit ican3_init_fast_host_interface(struct ican3_dev *mod)
+{
+ struct ican3_fast_desc desc;
+ unsigned long flags;
+ unsigned int addr;
+ void __iomem *dst;
+ int i;
+
+ spin_lock_irqsave(&mod->lock, flags);
+
+ /* save the start recv page */
+ mod->fastrx_start = mod->free_page;
+ mod->fastrx_num = 0;
+ mod->fastrx_int = 0;
+
+ /* build a single fast tohost queue descriptor */
+ memset(&desc, 0, sizeof(desc));
+ desc.control = 0x00;
+ desc.command = 1;
+
+ /* build the tohost queue descriptor ring in memory */
+ addr = 0;
+ for (i = 0; i < ICAN3_RX_BUFFERS; i++) {
+
+ /* set the wrap bit on the last buffer */
+ if (i == ICAN3_RX_BUFFERS - 1)
+ desc.control |= DESC_WRAP;
+
+ /* switch to the correct page */
+ ican3_set_page(mod, mod->free_page);
+
+ /* copy the descriptor to the DPM */
+ dst = mod->dpm + addr;
+ memcpy_toio(dst, &desc, sizeof(desc));
+ addr += sizeof(desc);
+
+ /* move to the next page if necessary */
+ if (addr >= DPM_PAGE_SIZE) {
+ addr = 0;
+ mod->free_page++;
+ }
+ }
+
+ /* make sure we page-align the next queue */
+ if (addr != 0)
+ mod->free_page++;
+
+ /* save the start xmit page */
+ mod->fasttx_start = mod->free_page;
+ mod->fasttx_num = 0;
+
+ /* build a single fast fromhost queue descriptor */
+ memset(&desc, 0, sizeof(desc));
+ desc.control = DESC_VALID;
+ desc.command = 1;
+
+ /* build the fromhost queue descriptor ring in memory */
+ addr = 0;
+ for (i = 0; i < ICAN3_TX_BUFFERS; i++) {
+
+ /* set the wrap bit on the last buffer */
+ if (i == ICAN3_TX_BUFFERS - 1)
+ desc.control |= DESC_WRAP;
+
+ /* switch to the correct page */
+ ican3_set_page(mod, mod->free_page);
+
+ /* copy the descriptor to the DPM */
+ dst = mod->dpm + addr;
+ memcpy_toio(dst, &desc, sizeof(desc));
+ addr += sizeof(desc);
+
+ /* move to the next page if necessary */
+ if (addr >= DPM_PAGE_SIZE) {
+ addr = 0;
+ mod->free_page++;
+ }
+ }
+
+ spin_unlock_irqrestore(&mod->lock, flags);
+}
+
+/*
+ * ICAN3 "new-style" Host Interface Message Helpers
+ */
+
+/*
+ * LOCKING: must hold mod->lock
+ */
+static int ican3_new_send_msg(struct ican3_dev *mod, struct ican3_msg *msg)
+{
+ struct ican3_new_desc desc;
+ void __iomem *desc_addr = mod->dpm + (mod->tx_num * sizeof(desc));
+
+ /* switch to the fromhost mid queue, and read the buffer descriptor */
+ ican3_set_page(mod, QUEUE_FROMHOST_MID);
+ memcpy_fromio(&desc, desc_addr, sizeof(desc));
+
+ if (!(desc.control & DESC_VALID)) {
+ dev_dbg(mod->dev, "%s: no free buffers\n", __func__);
+ return -ENOMEM;
+ }
+
+ /* switch to the data page, copy the data */
+ ican3_set_page(mod, desc.pointer);
+ memcpy_toio(mod->dpm, msg, sizeof(*msg));
+
+ /* switch back to the descriptor, set the valid bit, write it back */
+ ican3_set_page(mod, QUEUE_FROMHOST_MID);
+ desc.control ^= DESC_VALID;
+ memcpy_toio(desc_addr, &desc, sizeof(desc));
+
+ /* update the tx number */
+ mod->tx_num = (desc.control & DESC_WRAP) ? 0 : (mod->tx_num + 1);
+ return 0;
+}
+
+/*
+ * LOCKING: must hold mod->lock
+ */
+static int ican3_new_recv_msg(struct ican3_dev *mod, struct ican3_msg *msg)
+{
+ struct ican3_new_desc desc;
+ void __iomem *desc_addr = mod->dpm + (mod->rx_num * sizeof(desc));
+
+ /* switch to the tohost queue, and read the buffer descriptor */
+ ican3_set_page(mod, QUEUE_TOHOST);
+ memcpy_fromio(&desc, desc_addr, sizeof(desc));
+
+ if (!(desc.control & DESC_VALID)) {
+ dev_dbg(mod->dev, "%s: no buffers to recv\n", __func__);
+ return -ENOMEM;
+ }
+
+ /* switch to the data page, copy the data */
+ ican3_set_page(mod, desc.pointer);
+ memcpy_fromio(msg, mod->dpm, sizeof(*msg));
+
+ /* switch back to the descriptor, toggle the valid bit, write it back */
+ ican3_set_page(mod, QUEUE_TOHOST);
+ desc.control ^= DESC_VALID;
+ memcpy_toio(desc_addr, &desc, sizeof(desc));
+
+ /* update the rx number */
+ mod->rx_num = (desc.control & DESC_WRAP) ? 0 : (mod->rx_num + 1);
+ return 0;
+}
+
+/*
+ * Message Send / Recv Helpers
+ */
+
+static int ican3_send_msg(struct ican3_dev *mod, struct ican3_msg *msg)
+{
+ unsigned long flags;
+ int ret;
+
+ spin_lock_irqsave(&mod->lock, flags);
+
+ if (mod->iftype == 0)
+ ret = ican3_old_send_msg(mod, msg);
+ else
+ ret = ican3_new_send_msg(mod, msg);
+
+ spin_unlock_irqrestore(&mod->lock, flags);
+ return ret;
+}
+
+static int ican3_recv_msg(struct ican3_dev *mod, struct ican3_msg *msg)
+{
+ unsigned long flags;
+ int ret;
+
+ spin_lock_irqsave(&mod->lock, flags);
+
+ if (mod->iftype == 0)
+ ret = ican3_old_recv_msg(mod, msg);
+ else
+ ret = ican3_new_recv_msg(mod, msg);
+
+ spin_unlock_irqrestore(&mod->lock, flags);
+ return ret;
+}
+
+/*
+ * Quick Pre-constructed Messages
+ */
+
+static int __devinit ican3_msg_connect(struct ican3_dev *mod)
+{
+ struct ican3_msg msg;
+
+ memset(&msg, 0, sizeof(msg));
+ msg.spec = MSG_CONNECTI;
+ msg.len = cpu_to_le16(0);
+
+ return ican3_send_msg(mod, &msg);
+}
+
+static int __devexit ican3_msg_disconnect(struct ican3_dev *mod)
+{
+ struct ican3_msg msg;
+
+ memset(&msg, 0, sizeof(msg));
+ msg.spec = MSG_DISCONNECT;
+ msg.len = cpu_to_le16(0);
+
+ return ican3_send_msg(mod, &msg);
+}
+
+static int __devinit ican3_msg_newhostif(struct ican3_dev *mod)
+{
+ struct ican3_msg msg;
+ int ret;
+
+ memset(&msg, 0, sizeof(msg));
+ msg.spec = MSG_NEWHOSTIF;
+ msg.len = cpu_to_le16(0);
+
+ /* If we're not using the old interface, switching seems bogus */
+ WARN_ON(mod->iftype != 0);
+
+ ret = ican3_send_msg(mod, &msg);
+ if (ret)
+ return ret;
+
+ /* mark the module as using the new host interface */
+ mod->iftype = 1;
+ return 0;
+}
+
+static int __devinit ican3_msg_fasthostif(struct ican3_dev *mod)
+{
+ struct ican3_msg msg;
+ unsigned int addr;
+
+ memset(&msg, 0, sizeof(msg));
+ msg.spec = MSG_INITFDPMQUEUE;
+ msg.len = cpu_to_le16(8);
+
+ /* write the tohost queue start address */
+ addr = DPM_PAGE_ADDR(mod->fastrx_start);
+ msg.data[0] = addr & 0xff;
+ msg.data[1] = (addr >> 8) & 0xff;
+ msg.data[2] = (addr >> 16) & 0xff;
+ msg.data[3] = (addr >> 24) & 0xff;
+
+ /* write the fromhost queue start address */
+ addr = DPM_PAGE_ADDR(mod->fasttx_start);
+ msg.data[4] = addr & 0xff;
+ msg.data[5] = (addr >> 8) & 0xff;
+ msg.data[6] = (addr >> 16) & 0xff;
+ msg.data[7] = (addr >> 24) & 0xff;
+
+ /* If we're not using the new interface yet, we cannot do this */
+ WARN_ON(mod->iftype != 1);
+
+ return ican3_send_msg(mod, &msg);
+}
+
+/*
+ * Setup the CAN filter to either accept or reject all
+ * messages from the CAN bus.
+ */
+static int __devinit ican3_set_id_filter(struct ican3_dev *mod, bool accept)
+{
+ struct ican3_msg msg;
+ int ret;
+
+ /* Standard Frame Format */
+ memset(&msg, 0, sizeof(msg));
+ msg.spec = MSG_SETAFILMASK;
+ msg.len = cpu_to_le16(5);
+ msg.data[0] = 0x00; /* IDLo LSB */
+ msg.data[1] = 0x00; /* IDLo MSB */
+ msg.data[2] = 0xff; /* IDHi LSB */
+ msg.data[3] = 0x07; /* IDHi MSB */
+
+ /* accept all frames for fast host if, or reject all frames */
+ msg.data[4] = accept ? SETAFILMASK_FASTIF : SETAFILMASK_REJECT;
+
+ ret = ican3_send_msg(mod, &msg);
+ if (ret)
+ return ret;
+
+ /* Extended Frame Format */
+ memset(&msg, 0, sizeof(msg));
+ msg.spec = MSG_SETAFILMASK;
+ msg.len = cpu_to_le16(13);
+ msg.data[0] = 0; /* MUX = 0 */
+ msg.data[1] = 0x00; /* IDLo LSB */
+ msg.data[2] = 0x00;
+ msg.data[3] = 0x00;
+ msg.data[4] = 0x20; /* IDLo MSB */
+ msg.data[5] = 0xff; /* IDHi LSB */
+ msg.data[6] = 0xff;
+ msg.data[7] = 0xff;
+ msg.data[8] = 0x3f; /* IDHi MSB */
+
+ /* accept all frames for fast host if, or reject all frames */
+ msg.data[9] = accept ? SETAFILMASK_FASTIF : SETAFILMASK_REJECT;
+
+ return ican3_send_msg(mod, &msg);
+}
+
+/*
+ * Bring the CAN bus online or offline
+ */
+static int ican3_set_bus_state(struct ican3_dev *mod, bool on)
+{
+ struct ican3_msg msg;
+
+ memset(&msg, 0, sizeof(msg));
+ msg.spec = on ? MSG_CONREQ : MSG_COFFREQ;
+ msg.len = cpu_to_le16(0);
+
+ return ican3_send_msg(mod, &msg);
+}
+
+static int __devinit ican3_set_termination(struct ican3_dev *mod, bool on)
+{
+ struct ican3_msg msg;
+
+ memset(&msg, 0, sizeof(msg));
+ msg.spec = MSG_HWCONF;
+ msg.len = cpu_to_le16(2);
+ msg.data[0] = 0x00;
+ msg.data[1] = on ? HWCONF_TERMINATE_ON : HWCONF_TERMINATE_OFF;
+
+ return ican3_send_msg(mod, &msg);
+}
+
+static int __devinit ican3_set_buserror(struct ican3_dev *mod, u8 quota)
+{
+ struct ican3_msg msg;
+
+ memset(&msg, 0, sizeof(msg));
+ msg.spec = MSG_CCONFREQ;
+ msg.len = cpu_to_le16(2);
+ msg.data[0] = 0x00;
+ msg.data[1] = quota;
+
+ return ican3_send_msg(mod, &msg);
+}
+
+/*
+ * ICAN3 to Linux CAN Frame Conversion
+ */
+
+static void ican3_to_can_frame(struct ican3_dev *mod,
+ struct ican3_fast_desc *desc,
+ struct can_frame *cf)
+{
+ if ((desc->command & ICAN3_CAN_TYPE_MASK) == ICAN3_CAN_TYPE_SFF) {
+ dev_dbg(mod->dev, "%s: old frame format\n", __func__);
+ if (desc->data[1] & ICAN3_SFF_RTR)
+ cf->can_id |= CAN_RTR_FLAG;
+
+ cf->can_id |= desc->data[0] << 3;
+ cf->can_id |= (desc->data[1] & 0xe0) >> 5;
+ cf->can_dlc = desc->data[1] & ICAN3_CAN_DLC_MASK;
+ memcpy(cf->data, &desc->data[2], sizeof(cf->data));
+ } else {
+ dev_dbg(mod->dev, "%s: new frame format\n", __func__);
+ cf->can_dlc = desc->data[0] & ICAN3_CAN_DLC_MASK;
+ if (desc->data[0] & ICAN3_EFF_RTR)
+ cf->can_id |= CAN_RTR_FLAG;
+
+ if (desc->data[0] & ICAN3_EFF) {
+ cf->can_id |= CAN_EFF_FLAG;
+ cf->can_id |= desc->data[2] << 21; /* 28-21 */
+ cf->can_id |= desc->data[3] << 13; /* 20-13 */
+ cf->can_id |= desc->data[4] << 5; /* 12-5 */
+ cf->can_id |= (desc->data[5] & 0xf8) >> 3;
+ } else {
+ cf->can_id |= desc->data[2] << 3; /* 10-3 */
+ cf->can_id |= desc->data[3] >> 5; /* 2-0 */
+ }
+
+ memcpy(cf->data, &desc->data[6], sizeof(cf->data));
+ }
+}
+
+static void can_frame_to_ican3(struct ican3_dev *mod,
+ struct can_frame *cf,
+ struct ican3_fast_desc *desc)
+{
+ /* clear out any stale data in the descriptor */
+ memset(desc->data, 0, sizeof(desc->data));
+
+ /* we always use the extended format, with the ECHO flag set */
+ desc->command = ICAN3_CAN_TYPE_EFF;
+ desc->data[0] |= cf->can_dlc;
+ desc->data[1] |= ICAN3_ECHO;
+
+ if (cf->can_id & CAN_RTR_FLAG)
+ desc->data[0] |= ICAN3_EFF_RTR;
+
+ /* pack the id into the correct places */
+ if (cf->can_id & CAN_EFF_FLAG) {
+ dev_dbg(mod->dev, "%s: extended frame\n", __func__);
+ desc->data[0] |= ICAN3_EFF;
+ desc->data[2] = (cf->can_id & 0x1fe00000) >> 21; /* 28-21 */
+ desc->data[3] = (cf->can_id & 0x001fe000) >> 13; /* 20-13 */
+ desc->data[4] = (cf->can_id & 0x00001fe0) >> 5; /* 12-5 */
+ desc->data[5] = (cf->can_id & 0x0000001f) << 3; /* 4-0 */
+ } else {
+ dev_dbg(mod->dev, "%s: standard frame\n", __func__);
+ desc->data[2] = (cf->can_id & 0x7F8) >> 3; /* bits 10-3 */
+ desc->data[3] = (cf->can_id & 0x007) << 5; /* bits 2-0 */
+ }
+
+ /* copy the data bits into the descriptor */
+ memcpy(&desc->data[6], cf->data, sizeof(cf->data));
+}
+
+/*
+ * Interrupt Handling
+ */
+
+/*
+ * Handle an ID + Version message response from the firmware. We never generate
+ * this message in production code, but it is very useful when debugging to be
+ * able to display this message.
+ */
+static void ican3_handle_idvers(struct ican3_dev *mod, struct ican3_msg *msg)
+{
+ dev_dbg(mod->dev, "IDVERS response: %s\n", msg->data);
+}
+
+static void ican3_handle_msglost(struct ican3_dev *mod, struct ican3_msg *msg)
+{
+ struct net_device *dev = mod->ndev;
+ struct net_device_stats *stats = &dev->stats;
+ struct can_frame *cf;
+ struct sk_buff *skb;
+
+ /*
+ * Report that communication messages with the microcontroller firmware
+ * are being lost. These are never CAN frames, so we do not generate an
+ * error frame for userspace
+ */
+ if (msg->spec == MSG_MSGLOST) {
+ dev_err(mod->dev, "lost %d control messages\n", msg->data[0]);
+ return;
+ }
+
+ /*
+ * Oops, this indicates that we have lost messages in the fast queue,
+ * which are exclusively CAN messages. Our driver isn't reading CAN
+ * frames fast enough.
+ *
+ * We'll pretend that the SJA1000 told us that it ran out of buffer
+ * space, because there is not a better message for this.
+ */
+ skb = alloc_can_err_skb(dev, &cf);
+ if (skb) {
+ cf->can_id |= CAN_ERR_CRTL;
+ cf->data[1] = CAN_ERR_CRTL_RX_OVERFLOW;
+ stats->rx_errors++;
+ stats->rx_bytes += cf->can_dlc;
+ netif_rx(skb);
+ }
+}
+
+/*
+ * Handle CAN Event Indication Messages from the firmware
+ *
+ * The ICAN3 firmware provides the values of some SJA1000 registers when it
+ * generates this message. The code below is largely copied from the
+ * drivers/net/can/sja1000/sja1000.c file, and adapted as necessary
+ */
+static int ican3_handle_cevtind(struct ican3_dev *mod, struct ican3_msg *msg)
+{
+ struct net_device *dev = mod->ndev;
+ struct net_device_stats *stats = &dev->stats;
+ enum can_state state = mod->can.state;
+ struct can_frame *cf;
+ struct sk_buff *skb;
+ u8 status, isrc;
+
+ /* we can only handle the SJA1000 part */
+ if (msg->data[1] != CEVTIND_CHIP_SJA1000) {
+ dev_err(mod->dev, "unable to handle errors on non-SJA1000\n");
+ return -ENODEV;
+ }
+
+ /* check the message length for sanity */
+ if (msg->len < 6) {
+ dev_err(mod->dev, "error message too short\n");
+ return -EINVAL;
+ }
+
+ skb = alloc_can_err_skb(dev, &cf);
+ if (skb == NULL)
+ return -ENOMEM;
+
+ isrc = msg->data[0];
+ status = msg->data[3];
+
+ /* data overrun interrupt */
+ if (isrc == CEVTIND_DOI || isrc == CEVTIND_LOST) {
+ cf->can_id |= CAN_ERR_CRTL;
+ cf->data[1] = CAN_ERR_CRTL_RX_OVERFLOW;
+ stats->rx_over_errors++;
+ stats->rx_errors++;
+ dev_info(mod->dev, "%s: overflow frame generated\n", __func__);
+ }
+
+ /* error warning interrupt */
+ if (isrc == CEVTIND_EI) {
+ if (status & SR_BS) {
+ state = CAN_STATE_BUS_OFF;
+ cf->can_id |= CAN_ERR_BUSOFF;
+ can_bus_off(dev);
+ } else if (status & SR_ES) {
+ state = CAN_STATE_ERROR_WARNING;
+ } else {
+ state = CAN_STATE_ERROR_ACTIVE;
+ }
+ }
+
+ /* bus error interrupt */
+ if (isrc == CEVTIND_BEI) {
+ u8 ecc = msg->data[2];
+ mod->can.can_stats.bus_error++;
+ stats->rx_errors++;
+ cf->can_id |= CAN_ERR_PROT | CAN_ERR_BUSERROR;
+
+ switch (ecc & ECC_MASK) {
+ case ECC_BIT:
+ cf->data[2] |= CAN_ERR_PROT_BIT;
+ break;
+ case ECC_FORM:
+ cf->data[2] |= CAN_ERR_PROT_FORM;
+ break;
+ case ECC_STUFF:
+ cf->data[2] |= CAN_ERR_PROT_STUFF;
+ break;
+ default:
+ cf->data[2] |= CAN_ERR_PROT_UNSPEC;
+ cf->data[3] = ecc & ECC_SEG;
+ break;
+ }
+
+ if ((ecc & ECC_DIR) == 0)
+ cf->data[2] |= CAN_ERR_PROT_TX;
+ }
+
+ if (state != mod->can.state && (state == CAN_STATE_ERROR_WARNING ||
+ state == CAN_STATE_ERROR_PASSIVE)) {
+ u8 rxerr = msg->data[4];
+ u8 txerr = msg->data[5];
+ cf->can_id |= CAN_ERR_CRTL;
+ if (state == CAN_STATE_ERROR_WARNING) {
+ mod->can.can_stats.error_warning++;
+ cf->data[1] = (txerr > rxerr) ?
+ CAN_ERR_CRTL_TX_WARNING :
+ CAN_ERR_CRTL_RX_WARNING;
+ } else {
+ mod->can.can_stats.error_passive++;
+ cf->data[1] = (txerr > rxerr) ?
+ CAN_ERR_CRTL_TX_PASSIVE :
+ CAN_ERR_CRTL_RX_PASSIVE;
+ }
+ }
+
+ mod->can.state = state;
+ stats->rx_errors++;
+ stats->rx_bytes += cf->can_dlc;
+ netif_rx(skb);
+ return 0;
+}
+
+static void ican3_handle_unknown_message(struct ican3_dev *mod,
+ struct ican3_msg *msg)
+{
+ dev_warn(mod->dev, "recieved unknown message: spec 0x%.2x length %d\n",
+ msg->spec, le16_to_cpu(msg->len));
+}
+
+/*
+ * Handle a control message from the firmware
+ */
+static void ican3_handle_message(struct ican3_dev *mod, struct ican3_msg *msg)
+{
+ dev_dbg(mod->dev, "%s: modno %d spec 0x%.2x len %d bytes\n", __func__,
+ mod->num, msg->spec, le16_to_cpu(msg->len));
+
+ switch (msg->spec) {
+ case MSG_IDVERS:
+ ican3_handle_idvers(mod, msg);
+ break;
+ case MSG_MSGLOST:
+ case MSG_FMSGLOST:
+ ican3_handle_msglost(mod, msg);
+ break;
+ case MSG_CEVTIND:
+ ican3_handle_cevtind(mod, msg);
+ break;
+ default:
+ ican3_handle_unknown_message(mod, msg);
+ break;
+ }
+}
+
+/*
+ * Check that there is room in the TX ring to transmit another skb
+ *
+ * LOCKING: must hold mod->lock
+ */
+static bool ican3_txok(struct ican3_dev *mod)
+{
+ struct ican3_fast_desc __iomem *desc;
+ u8 control;
+
+ /* copy the control bits of the descriptor */
+ ican3_set_page(mod, mod->fasttx_start + (mod->fasttx_num / 16));
+ desc = mod->dpm + ((mod->fasttx_num % 16) * sizeof(*desc));
+ control = ioread8(&desc->control);
+
+ /* if the control bits are not valid, then we have no more space */
+ if (!(control & DESC_VALID))
+ return false;
+
+ return true;
+}
+
+/*
+ * Recieve one CAN frame from the hardware
+ *
+ * This works like the core of a NAPI function, but is intended to be called
+ * from workqueue context instead. This driver already needs a workqueue to
+ * process control messages, so we use the workqueue instead of using NAPI.
+ * This was done to simplify locking.
+ *
+ * CONTEXT: must be called from user context
+ */
+static int ican3_recv_skb(struct ican3_dev *mod)
+{
+ struct net_device *ndev = mod->ndev;
+ struct net_device_stats *stats = &ndev->stats;
+ struct ican3_fast_desc desc;
+ void __iomem *desc_addr;
+ struct can_frame *cf;
+ struct sk_buff *skb;
+ unsigned long flags;
+
+ spin_lock_irqsave(&mod->lock, flags);
+
+ /* copy the whole descriptor */
+ ican3_set_page(mod, mod->fastrx_start + (mod->fastrx_num / 16));
+ desc_addr = mod->dpm + ((mod->fastrx_num % 16) * sizeof(desc));
+ memcpy_fromio(&desc, desc_addr, sizeof(desc));
+
+ spin_unlock_irqrestore(&mod->lock, flags);
+
+ /* check that we actually have a CAN frame */
+ if (!(desc.control & DESC_VALID))
+ return -ENOBUFS;
+
+ /* allocate an skb */
+ skb = alloc_can_skb(ndev, &cf);
+ if (unlikely(skb == NULL)) {
+ stats->rx_dropped++;
+ goto err_noalloc;
+ }
+
+ /* convert the ICAN3 frame into Linux CAN format */
+ ican3_to_can_frame(mod, &desc, cf);
+
+ /* receive the skb, update statistics */
+ netif_receive_skb(skb);
+ stats->rx_packets++;
+ stats->rx_bytes += cf->can_dlc;
+
+err_noalloc:
+ /* toggle the valid bit and return the descriptor to the ring */
+ desc.control ^= DESC_VALID;
+
+ spin_lock_irqsave(&mod->lock, flags);
+
+ ican3_set_page(mod, mod->fastrx_start + (mod->fastrx_num / 16));
+ memcpy_toio(desc_addr, &desc, 1);
+
+ /* update the next buffer pointer */
+ mod->fastrx_num = (desc.control & DESC_WRAP) ? 0
+ : (mod->fastrx_num + 1);
+
+ /* there are still more buffers to process */
+ spin_unlock_irqrestore(&mod->lock, flags);
+ return 0;
+}
+
+static int ican3_napi(struct napi_struct *napi, int budget)
+{
+ struct ican3_dev *mod = container_of(napi, struct ican3_dev, napi);
+ struct ican3_msg msg;
+ unsigned long flags;
+ int received = 0;
+ int ret;
+
+ /* process all communication messages */
+ while (true) {
+ ret = ican3_recv_msg(mod, &msg);
+ if (ret)
+ break;
+
+ ican3_handle_message(mod, &msg);
+ }
+
+ /* process all CAN frames from the fast interface */
+ while (received < budget) {
+ ret = ican3_recv_skb(mod);
+ if (ret)
+ break;
+
+ received++;
+ }
+
+ /* We have processed all packets that the adapter had, but it
+ * was less than our budget, stop polling */
+ if (received < budget)
+ napi_complete(napi);
+
+ spin_lock_irqsave(&mod->lock, flags);
+
+ /* Wake up the transmit queue if necessary */
+ if (netif_queue_stopped(mod->ndev) && ican3_txok(mod))
+ netif_wake_queue(mod->ndev);
+
+ spin_unlock_irqrestore(&mod->lock, flags);
+
+ /* re-enable interrupt generation */
+ iowrite8(1 << mod->num, &mod->ctrl->int_enable);
+ return received;
+}
+
+static irqreturn_t ican3_irq(int irq, void *dev_id)
+{
+ struct ican3_dev *mod = dev_id;
+ u8 stat;
+
+ /*
+ * The interrupt status register on this device reports interrupts
+ * as zeroes instead of using ones like most other devices
+ */
+ stat = ioread8(&mod->ctrl->int_disable) & (1 << mod->num);
+ if (stat == (1 << mod->num))
+ return IRQ_NONE;
+
+ dev_dbg(mod->dev, "IRQ: module %d\n", mod->num);
+
+ /* clear the MODULbus interrupt from the microcontroller */
+ ioread8(&mod->dpmctrl->interrupt);
+
+ /* disable interrupt generation, schedule the NAPI poller */
+ iowrite8(1 << mod->num, &mod->ctrl->int_disable);
+ napi_schedule(&mod->napi);
+ return IRQ_HANDLED;
+}
+
+/*
+ * Firmware reset, startup, and shutdown
+ */
+
+/*
+ * Reset an ICAN module to its power-on state
+ *
+ * CONTEXT: no network device registered
+ * LOCKING: work function disabled
+ */
+static int ican3_reset_module(struct ican3_dev *mod)
+{
+ u8 val = 1 << mod->num;
+ unsigned long start;
+ u8 runold, runnew;
+
+ /* disable interrupts so no more work is scheduled */
+ iowrite8(1 << mod->num, &mod->ctrl->int_disable);
+
+ /* flush any pending work */
+ flush_scheduled_work();
+
+ /* the first unallocated page in the DPM is #9 */
+ mod->free_page = DPM_FREE_START;
+
+ ican3_set_page(mod, QUEUE_OLD_CONTROL);
+ runold = ioread8(mod->dpm + TARGET_RUNNING);
+
+ /* reset the module */
+ iowrite8(val, &mod->ctrl->reset_assert);
+ iowrite8(val, &mod->ctrl->reset_deassert);
+
+ /* wait until the module has finished resetting and is running */
+ start = jiffies;
+ do {
+ ican3_set_page(mod, QUEUE_OLD_CONTROL);
+ runnew = ioread8(mod->dpm + TARGET_RUNNING);
+ if (runnew == (runold ^ 0xff))
+ return 0;
+
+ msleep(10);
+ } while (time_before(jiffies, start + HZ / 4));
+
+ dev_err(mod->dev, "failed to reset CAN module\n");
+ return -ETIMEDOUT;
+}
+
+static void __devexit ican3_shutdown_module(struct ican3_dev *mod)
+{
+ ican3_msg_disconnect(mod);
+ ican3_reset_module(mod);
+}
+
+/*
+ * Startup an ICAN module, bringing it into fast mode
+ */
+static int __devinit ican3_startup_module(struct ican3_dev *mod)
+{
+ int ret;
+
+ ret = ican3_reset_module(mod);
+ if (ret) {
+ dev_err(mod->dev, "unable to reset module\n");
+ return ret;
+ }
+
+ /* re-enable interrupts so we can send messages */
+ iowrite8(1 << mod->num, &mod->ctrl->int_enable);
+
+ ret = ican3_msg_connect(mod);
+ if (ret) {
+ dev_err(mod->dev, "unable to connect to module\n");
+ return ret;
+ }
+
+ ican3_init_new_host_interface(mod);
+ ret = ican3_msg_newhostif(mod);
+ if (ret) {
+ dev_err(mod->dev, "unable to switch to new-style interface\n");
+ return ret;
+ }
+
+ ret = ican3_set_termination(mod, true);
+ if (ret) {
+ dev_err(mod->dev, "unable to enable termination\n");
+ return ret;
+ }
+
+ ret = ican3_set_buserror(mod, ICAN3_BUSERR_QUOTA_MAX);
+ if (ret) {
+ dev_err(mod->dev, "unable to set bus-error\n");
+ return ret;
+ }
+
+ ican3_init_fast_host_interface(mod);
+ ret = ican3_msg_fasthostif(mod);
+ if (ret) {
+ dev_err(mod->dev, "unable to switch to fast host interface\n");
+ return ret;
+ }
+
+ ret = ican3_set_id_filter(mod, true);
+ if (ret) {
+ dev_err(mod->dev, "unable to set acceptance filter\n");
+ return ret;
+ }
+
+ return 0;
+}
+
+/*
+ * CAN Network Device
+ */
+
+static int ican3_open(struct net_device *ndev)
+{
+ struct ican3_dev *mod = netdev_priv(ndev);
+ int ret;
+
+ /* open the CAN layer */
+ ret = open_candev(ndev);
+ if (ret) {
+ dev_err(mod->dev, "unable to start CAN layer\n");
+ return ret;
+ }
+
+ /* bring the bus online */
+ ret = ican3_set_bus_state(mod, true);
+ if (ret) {
+ dev_err(mod->dev, "unable to set bus-on\n");
+ close_candev(ndev);
+ return ret;
+ }
+
+ /* start up the network device */
+ mod->can.state = CAN_STATE_ERROR_ACTIVE;
+ netif_start_queue(ndev);
+
+ return 0;
+}
+
+static int ican3_stop(struct net_device *ndev)
+{
+ struct ican3_dev *mod = netdev_priv(ndev);
+ int ret;
+
+ /* stop the network device xmit routine */
+ netif_stop_queue(ndev);
+ mod->can.state = CAN_STATE_STOPPED;
+
+ /* bring the bus offline, stop receiving packets */
+ ret = ican3_set_bus_state(mod, false);
+ if (ret) {
+ dev_err(mod->dev, "unable to set bus-off\n");
+ return ret;
+ }
+
+ /* close the CAN layer */
+ close_candev(ndev);
+ return 0;
+}
+
+static int ican3_xmit(struct sk_buff *skb, struct net_device *ndev)
+{
+ struct ican3_dev *mod = netdev_priv(ndev);
+ struct net_device_stats *stats = &ndev->stats;
+ struct can_frame *cf = (struct can_frame *)skb->data;
+ struct ican3_fast_desc desc;
+ void __iomem *desc_addr;
+ unsigned long flags;
+
+ spin_lock_irqsave(&mod->lock, flags);
+
+ /* check that we can actually transmit */
+ if (!ican3_txok(mod)) {
+ dev_err(mod->dev, "no free descriptors, stopping queue\n");
+ netif_stop_queue(ndev);
+ spin_unlock_irqrestore(&mod->lock, flags);
+ return NETDEV_TX_BUSY;
+ }
+
+ /* copy the control bits of the descriptor */
+ ican3_set_page(mod, mod->fasttx_start + (mod->fasttx_num / 16));
+ desc_addr = mod->dpm + ((mod->fasttx_num % 16) * sizeof(desc));
+ memset(&desc, 0, sizeof(desc));
+ memcpy_fromio(&desc, desc_addr, 1);
+
+ /* convert the Linux CAN frame into ICAN3 format */
+ can_frame_to_ican3(mod, cf, &desc);
+
+ /*
+ * the programming manual says that you must set the IVALID bit, then
+ * interrupt, then set the valid bit. Quite weird, but it seems to be
+ * required for this to work
+ */
+ desc.control |= DESC_IVALID;
+ memcpy_toio(desc_addr, &desc, sizeof(desc));
+
+ /* generate a MODULbus interrupt to the microcontroller */
+ iowrite8(0x01, &mod->dpmctrl->interrupt);
+
+ desc.control ^= DESC_VALID;
+ memcpy_toio(desc_addr, &desc, sizeof(desc));
+
+ /* update the next buffer pointer */
+ mod->fasttx_num = (desc.control & DESC_WRAP) ? 0
+ : (mod->fasttx_num + 1);
+
+ /* update statistics */
+ stats->tx_packets++;
+ stats->tx_bytes += cf->can_dlc;
+ kfree_skb(skb);
+
+ /*
+ * This hardware doesn't have TX-done notifications, so we'll try and
+ * emulate it the best we can using ECHO skbs. Get the next TX
+ * descriptor, and see if we have room to send. If not, stop the queue.
+ * It will be woken when the ECHO skb for the current packet is recv'd.
+ */
+
+ /* copy the control bits of the descriptor */
+ if (!ican3_txok(mod))
+ netif_stop_queue(ndev);
+
+ spin_unlock_irqrestore(&mod->lock, flags);
+ return NETDEV_TX_OK;
+}
+
+static const struct net_device_ops ican3_netdev_ops = {
+ .ndo_open = ican3_open,
+ .ndo_stop = ican3_stop,
+ .ndo_start_xmit = ican3_xmit,
+};
+
+/*
+ * Low-level CAN Device
+ */
+
+/* This structure was stolen from drivers/net/can/sja1000/sja1000.c */
+static struct can_bittiming_const ican3_bittiming_const = {
+ .name = DRV_NAME,
+ .tseg1_min = 1,
+ .tseg1_max = 16,
+ .tseg2_min = 1,
+ .tseg2_max = 8,
+ .sjw_max = 4,
+ .brp_min = 1,
+ .brp_max = 64,
+ .brp_inc = 1,
+};
+
+/*
+ * This routine was stolen from drivers/net/can/sja1000/sja1000.c
+ *
+ * The bittiming register command for the ICAN3 just sets the bit timing
+ * registers on the SJA1000 chip directly
+ */
+static int ican3_set_bittiming(struct net_device *ndev)
+{
+ struct ican3_dev *mod = netdev_priv(ndev);
+ struct can_bittiming *bt = &mod->can.bittiming;
+ struct ican3_msg msg;
+ u8 btr0, btr1;
+
+ btr0 = ((bt->brp - 1) & 0x3f) | (((bt->sjw - 1) & 0x3) << 6);
+ btr1 = ((bt->prop_seg + bt->phase_seg1 - 1) & 0xf) |
+ (((bt->phase_seg2 - 1) & 0x7) << 4);
+ if (mod->can.ctrlmode & CAN_CTRLMODE_3_SAMPLES)
+ btr1 |= 0x80;
+
+ memset(&msg, 0, sizeof(msg));
+ msg.spec = MSG_CBTRREQ;
+ msg.len = cpu_to_le16(4);
+ msg.data[0] = 0x00;
+ msg.data[1] = 0x00;
+ msg.data[2] = btr0;
+ msg.data[3] = btr1;
+
+ return ican3_send_msg(mod, &msg);
+}
+
+static int ican3_set_mode(struct net_device *ndev, enum can_mode mode)
+{
+ struct ican3_dev *mod = netdev_priv(ndev);
+ int ret;
+
+ if (mode != CAN_MODE_START)
+ return -ENOTSUPP;
+
+ /* bring the bus online */
+ ret = ican3_set_bus_state(mod, true);
+ if (ret) {
+ dev_err(mod->dev, "unable to set bus-on\n");
+ return ret;
+ }
+
+ /* start up the network device */
+ mod->can.state = CAN_STATE_ERROR_ACTIVE;
+
+ if (netif_queue_stopped(ndev))
+ netif_wake_queue(ndev);
+
+ return 0;
+}
+
+/*
+ * PCI Subsystem
+ */
+
+static int __devinit ican3_probe(struct platform_device *pdev)
+{
+ struct janz_platform_data *pdata;
+ struct net_device *ndev;
+ struct ican3_dev *mod;
+ struct resource *res;
+ struct device *dev;
+ int ret;
+
+ pdata = pdev->dev.platform_data;
+ if (!pdata)
+ return -ENXIO;
+
+ dev_dbg(&pdev->dev, "probe: module number %d\n", pdata->modno);
+
+ /* save the struct device for printing */
+ dev = &pdev->dev;
+
+ /* allocate the CAN device and private data */
+ ndev = alloc_candev(sizeof(*mod), 0);
+ if (!ndev) {
+ dev_err(dev, "unable to allocate CANdev\n");
+ ret = -ENOMEM;
+ goto out_return;
+ }
+
+ platform_set_drvdata(pdev, ndev);
+ mod = netdev_priv(ndev);
+ mod->ndev = ndev;
+ mod->dev = &pdev->dev;
+ mod->num = pdata->modno;
+ netif_napi_add(ndev, &mod->napi, ican3_napi, ICAN3_RX_BUFFERS);
+ spin_lock_init(&mod->lock);
+
+ /* the first unallocated page in the DPM is 9 */
+ mod->free_page = DPM_FREE_START;
+
+ ndev->netdev_ops = &ican3_netdev_ops;
+ ndev->flags |= IFF_ECHO;
+ SET_NETDEV_DEV(ndev, &pdev->dev);
+
+ mod->can.clock.freq = 8000000;
+ mod->can.bittiming_const = &ican3_bittiming_const;
+ mod->can.do_set_bittiming = ican3_set_bittiming;
+ mod->can.do_set_mode = ican3_set_mode;
+
+ /* find our IRQ number */
+ mod->irq = platform_get_irq(pdev, 0);
+ if (mod->irq < 0) {
+ dev_err(dev, "IRQ line not found\n");
+ ret = -ENODEV;
+ goto out_free_ndev;
+ }
+
+ ndev->irq = mod->irq;
+
+ /* get access to the MODULbus registers for this module */
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (!res) {
+ dev_err(dev, "MODULbus registers not found\n");
+ ret = -ENODEV;
+ goto out_free_ndev;
+ }
+
+ mod->dpm = ioremap(res->start, resource_size(res));
+ if (!mod->dpm) {
+ dev_err(dev, "MODULbus registers not ioremap\n");
+ ret = -ENOMEM;
+ goto out_free_ndev;
+ }
+
+ mod->dpmctrl = mod->dpm + DPM_PAGE_SIZE;
+
+ /* get access to the control registers for this module */
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
+ if (!res) {
+ dev_err(dev, "CONTROL registers not found\n");
+ ret = -ENODEV;
+ goto out_iounmap_dpm;
+ }
+
+ mod->ctrl = ioremap(res->start, resource_size(res));
+ if (!mod->ctrl) {
+ dev_err(dev, "CONTROL registers not ioremap\n");
+ ret = -ENOMEM;
+ goto out_iounmap_dpm;
+ }
+
+ /* disable our IRQ, then hookup the IRQ handler */
+ iowrite8(1 << mod->num, &mod->ctrl->int_disable);
+ ret = request_irq(mod->irq, ican3_irq, IRQF_SHARED, DRV_NAME, mod);
+ if (ret) {
+ dev_err(dev, "unable to request IRQ\n");
+ goto out_iounmap_ctrl;
+ }
+
+ /* reset and initialize the CAN controller into fast mode */
+ napi_enable(&mod->napi);
+ ret = ican3_startup_module(mod);
+ if (ret) {
+ dev_err(dev, "%s: unable to start CANdev\n", __func__);
+ goto out_free_irq;
+ }
+
+ /* register with the Linux CAN layer */
+ ret = register_candev(ndev);
+ if (ret) {
+ dev_err(dev, "%s: unable to register CANdev\n", __func__);
+ goto out_free_irq;
+ }
+
+ dev_info(dev, "module %d: registered CAN device\n", pdata->modno);
+ return 0;
+
+out_free_irq:
+ napi_disable(&mod->napi);
+ iowrite8(1 << mod->num, &mod->ctrl->int_disable);
+ free_irq(mod->irq, mod);
+out_iounmap_ctrl:
+ iounmap(mod->ctrl);
+out_iounmap_dpm:
+ iounmap(mod->dpm);
+out_free_ndev:
+ free_candev(ndev);
+out_return:
+ return ret;
+}
+
+static int __devexit ican3_remove(struct platform_device *pdev)
+{
+ struct net_device *ndev = platform_get_drvdata(pdev);
+ struct ican3_dev *mod = netdev_priv(ndev);
+
+ /* unregister the netdevice, stop interrupts */
+ unregister_netdev(ndev);
+ napi_disable(&mod->napi);
+ iowrite8(1 << mod->num, &mod->ctrl->int_disable);
+ free_irq(mod->irq, mod);
+
+ /* put the module into reset */
+ ican3_shutdown_module(mod);
+
+ /* unmap all registers */
+ iounmap(mod->ctrl);
+ iounmap(mod->dpm);
+
+ free_candev(ndev);
+
+ return 0;
+}
+
+static struct platform_driver ican3_driver = {
+ .driver = {
+ .name = DRV_NAME,
+ .owner = THIS_MODULE,
+ },
+ .probe = ican3_probe,
+ .remove = __devexit_p(ican3_remove),
+};
+
+static int __init ican3_init(void)
+{
+ return platform_driver_register(&ican3_driver);
+}
+
+static void __exit ican3_exit(void)
+{
+ platform_driver_unregister(&ican3_driver);
+}
+
+MODULE_AUTHOR("Ira W. Snyder <iws@ovro.caltech.edu>");
+MODULE_DESCRIPTION("Janz MODULbus VMOD-ICAN3 Driver");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:janz-ican3");
+
+module_init(ican3_init);
+module_exit(ican3_exit);
--
1.5.4.3


\
 
 \ /
  Last update: 2010-03-02 22:25    [from the cache]
©2003-2011 Jasper Spaans