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Message-ID: <20100317193312.GF9783@ovro.caltech.edu>
Date: Wed, 17 Mar 2010 12:33:12 -0700
From: "Ira W. Snyder" <iws@...o.caltech.edu>
To: linux-kernel@...r.kernel.org, socketcan-core@...ts.berlios.de
Subject: Re: [PATCH 2/3] can: add support for Janz VMOD-ICAN3 Intelligent
CAN module
Hello SocketCAN folks,
Is there any feedback on this patch? I've waited two weeks without a
response to any part of the series. As this is the biggest patch in the
series, if you're fine with it, I think the other supporting patches
should be fairly uncontroversial.
Thanks,
Ira
On Tue, Mar 02, 2010 at 01:22:08PM -0800, Ira W. Snyder wrote:
> 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@...o.caltech.edu>
> Cc: socketcan-core@...ts.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@...o.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@...o.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
>
> _______________________________________________
> Socketcan-core mailing list
> Socketcan-core@...ts.berlios.de
> https://lists.berlios.de/mailman/listinfo/socketcan-core
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