cxacru.c

linux-2.6.15.6

/******************************************************************************
 *  cxacru.c  -  driver for USB ADSL modems based on
 *               Conexant AccessRunner chipset
 *
 *  Copyright (C) 2004 David Woodhouse, Duncan Sands, Roman Kagan
 *  Copyright (C) 2005 Duncan Sands, Roman Kagan (rkagan % mail ! ru)
 *
 *  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.
 *
 *  This program is distributed in the hope that it will be useful, but WITHOUT
 *  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 *  FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
 *  more details.
 *
 *  You should have received a copy of the GNU General Public License along with
 *  this program; if not, write to the Free Software Foundation, Inc., 59
 *  Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 *
 ******************************************************************************/

/*
 *  Credit is due for Josep Comas, who created the original patch to speedtch.c
 *  to support the different padding used by the AccessRunner (now generalized
 *  into usbatm), and the userspace firmware loading utility.
 */

#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/kernel.h>
#include <linux/timer.h>
#include <linux/errno.h>
#include <linux/slab.h>
#include <linux/init.h>
#include <linux/device.h>	/* FIXME: linux/firmware.h should include it itself */
#include <linux/firmware.h>

#include "usbatm.h"

#define DRIVER_AUTHOR	"Roman Kagan, David Woodhouse, Duncan Sands"
#define DRIVER_VERSION	"0.2"
#define DRIVER_DESC	"Conexant AccessRunner ADSL USB modem driver"

static const char cxacru_driver_name[] = "cxacru";

#define CXACRU_EP_CMD		0x01	/* Bulk/interrupt in/out */
#define CXACRU_EP_DATA		0x02	/* Bulk in/out */

#define CMD_PACKET_SIZE		64	/* Should be maxpacket(ep)? */

/* Addresses */
#define PLLFCLK_ADDR	0x00350068
#define PLLBCLK_ADDR	0x0035006c
#define SDRAMEN_ADDR	0x00350010
#define FW_ADDR		0x00801000
#define BR_ADDR		0x00180600
#define SIG_ADDR	0x00180500
#define BR_STACK_ADDR	0x00187f10

/* Values */
#define SDRAM_ENA	0x1

#define CMD_TIMEOUT	2000	/* msecs */
#define POLL_INTERVAL	5000	/* msecs */

/* commands for interaction with the modem through the control channel before
 * firmware is loaded  */
enum cxacru_fw_request {
	FW_CMD_ERR,
	FW_GET_VER,
	FW_READ_MEM,
	FW_WRITE_MEM,
	FW_RMW_MEM,
	FW_CHECKSUM_MEM,
	FW_GOTO_MEM,
};

/* commands for interaction with the modem through the control channel once
 * firmware is loaded  */
enum cxacru_cm_request {
	CM_REQUEST_UNDEFINED = 0x80,
	CM_REQUEST_TEST,
	CM_REQUEST_CHIP_GET_MAC_ADDRESS,
	CM_REQUEST_CHIP_GET_DP_VERSIONS,
	CM_REQUEST_CHIP_ADSL_LINE_START,
	CM_REQUEST_CHIP_ADSL_LINE_STOP,
	CM_REQUEST_CHIP_ADSL_LINE_GET_STATUS,
	CM_REQUEST_CHIP_ADSL_LINE_GET_SPEED,
	CM_REQUEST_CARD_INFO_GET,
	CM_REQUEST_CARD_DATA_GET,
	CM_REQUEST_CARD_DATA_SET,
	CM_REQUEST_COMMAND_HW_IO,
	CM_REQUEST_INTERFACE_HW_IO,
	CM_REQUEST_CARD_SERIAL_DATA_PATH_GET,
	CM_REQUEST_CARD_SERIAL_DATA_PATH_SET,
	CM_REQUEST_CARD_CONTROLLER_VERSION_GET,
	CM_REQUEST_CARD_GET_STATUS,
	CM_REQUEST_CARD_GET_MAC_ADDRESS,
	CM_REQUEST_CARD_GET_DATA_LINK_STATUS,
	CM_REQUEST_MAX,
};

/* reply codes to the commands above */
enum cxacru_cm_status {
	CM_STATUS_UNDEFINED,
	CM_STATUS_SUCCESS,
	CM_STATUS_ERROR,
	CM_STATUS_UNSUPPORTED,
	CM_STATUS_UNIMPLEMENTED,
	CM_STATUS_PARAMETER_ERROR,
	CM_STATUS_DBG_LOOPBACK,
	CM_STATUS_MAX,
};

/* indices into CARD_INFO_GET return array */
enum cxacru_info_idx {
	CXINF_DOWNSTREAM_RATE,
	CXINF_UPSTREAM_RATE,
	CXINF_LINK_STATUS,
	CXINF_LINE_STATUS,
	CXINF_MAC_ADDRESS_HIGH,
	CXINF_MAC_ADDRESS_LOW,
	CXINF_UPSTREAM_SNR_MARGIN,
	CXINF_DOWNSTREAM_SNR_MARGIN,
	CXINF_UPSTREAM_ATTENUATION,
	CXINF_DOWNSTREAM_ATTENUATION,
	CXINF_TRANSMITTER_POWER,
	CXINF_UPSTREAM_BITS_PER_FRAME,
	CXINF_DOWNSTREAM_BITS_PER_FRAME,
	CXINF_STARTUP_ATTEMPTS,
	CXINF_UPSTREAM_CRC_ERRORS,
	CXINF_DOWNSTREAM_CRC_ERRORS,
	CXINF_UPSTREAM_FEC_ERRORS,
	CXINF_DOWNSTREAM_FEC_ERRORS,
	CXINF_UPSTREAM_HEC_ERRORS,
	CXINF_DOWNSTREAM_HEC_ERRORS,
	CXINF_LINE_STARTABLE,
	CXINF_MODULATION,
	CXINF_ADSL_HEADEND,
	CXINF_ADSL_HEADEND_ENVIRONMENT,
	CXINF_CONTROLLER_VERSION,
	/* dunno what the missing two mean */
	CXINF_MAX = 0x1c,
};

struct cxacru_modem_type {
	u32 pll_f_clk;
	u32 pll_b_clk;
	int boot_rom_patch;
};

struct cxacru_data {
	struct usbatm_data *usbatm;

	const struct cxacru_modem_type *modem_type;

	int line_status;
	struct work_struct poll_work;

	/* contol handles */
	struct semaphore cm_serialize;
	u8 *rcv_buf;
	u8 *snd_buf;
	struct urb *rcv_urb;
	struct urb *snd_urb;
	struct completion rcv_done;
	struct completion snd_done;
};

/* the following three functions are stolen from drivers/usb/core/message.c */
static void cxacru_blocking_completion(struct urb *urb, struct pt_regs *regs)
{
	complete((struct completion *)urb->context);
}

static void cxacru_timeout_kill(unsigned long data)
{
	usb_unlink_urb((struct urb *) data);
}

static int cxacru_start_wait_urb(struct urb *urb, struct completion *done,
				 int* actual_length)
{
	struct timer_list timer;
	int status;

	init_timer(&timer);
	timer.expires = jiffies + msecs_to_jiffies(CMD_TIMEOUT);
	timer.data = (unsigned long) urb;
	timer.function = cxacru_timeout_kill;
	add_timer(&timer);
	wait_for_completion(done);
	status = urb->status;
	if (status == -ECONNRESET)
		status = -ETIMEDOUT;
	del_timer_sync(&timer);

	if (actual_length)
		*actual_length = urb->actual_length;
	return status;
}

static int cxacru_cm(struct cxacru_data *instance, enum cxacru_cm_request cm,
		     u8 *wdata, int wsize, u8 *rdata, int rsize)
{
	int ret, actlen;
	int offb, offd;
	const int stride = CMD_PACKET_SIZE - 4;
	u8 *wbuf = instance->snd_buf;
	u8 *rbuf = instance->rcv_buf;
	int wbuflen = ((wsize - 1) / stride + 1) * CMD_PACKET_SIZE;
	int rbuflen = ((rsize - 1) / stride + 1) * CMD_PACKET_SIZE;

	if (wbuflen > PAGE_SIZE || rbuflen > PAGE_SIZE) {
		dbg("too big transfer requested");
		ret = -ENOMEM;
		goto fail;
	}

	down(&instance->cm_serialize);

	/* submit reading urb before the writing one */
	init_completion(&instance->rcv_done);
	ret = usb_submit_urb(instance->rcv_urb, GFP_KERNEL);
	if (ret < 0) {
		dbg("submitting read urb for cm %#x failed", cm);
		ret = ret;
		goto fail;
	}

	memset(wbuf, 0, wbuflen);
	/* handle wsize == 0 */
	wbuf[0] = cm;
	for (offb = offd = 0; offd < wsize; offd += stride, offb += CMD_PACKET_SIZE) {
		wbuf[offb] = cm;
		memcpy(wbuf + offb + 4, wdata + offd, min_t(int, stride, wsize - offd));
	}

	instance->snd_urb->transfer_buffer_length = wbuflen;
	init_completion(&instance->snd_done);
	ret = usb_submit_urb(instance->snd_urb, GFP_KERNEL);
	if (ret < 0) {
		dbg("submitting write urb for cm %#x failed", cm);
		ret = ret;
		goto fail;
	}

	ret = cxacru_start_wait_urb(instance->snd_urb, &instance->snd_done, NULL);
	if (ret < 0) {
		dbg("sending cm %#x failed", cm);
		ret = ret;
		goto fail;
	}

	ret = cxacru_start_wait_urb(instance->rcv_urb, &instance->rcv_done, &actlen);
	if (ret < 0) {
		dbg("receiving cm %#x failed", cm);
		ret = ret;
		goto fail;
	}
	if (actlen % CMD_PACKET_SIZE || !actlen) {
		dbg("response is not a positive multiple of %d: %#x",
				CMD_PACKET_SIZE, actlen);
		ret = -EIO;
		goto fail;
	}

	/* check the return status and copy the data to the output buffer, if needed */
	for (offb = offd = 0; offd < rsize && offb < actlen; offb += CMD_PACKET_SIZE) {
		if (rbuf[offb] != cm) {
			dbg("wrong cm %#x in response", rbuf[offb]);
			ret = -EIO;
			goto fail;
		}
		if (rbuf[offb + 1] != CM_STATUS_SUCCESS) {
			dbg("response failed: %#x", rbuf[offb + 1]);
			ret = -EIO;
			goto fail;
		}
		if (offd >= rsize)
			break;
		memcpy(rdata + offd, rbuf + offb + 4, min_t(int, stride, rsize - offd));
		offd += stride;
	}

	ret = offd;
	dbg("cm %#x", cm);
fail:
	up(&instance->cm_serialize);
	return ret;
}

static int cxacru_cm_get_array(struct cxacru_data *instance, enum cxacru_cm_request cm,
			       u32 *data, int size)
{
	int ret, len;
	u32 *buf;
	int offb, offd;
	const int stride = CMD_PACKET_SIZE / (4 * 2) - 1;
	int buflen =  ((size - 1) / stride + 1 + size * 2) * 4;

	buf = kmalloc(buflen, GFP_KERNEL);
	if (!buf)
		return -ENOMEM;

	ret = cxacru_cm(instance, cm, NULL, 0, (u8 *) buf, buflen);
	if (ret < 0)
		goto cleanup;

	/* len > 0 && len % 4 == 0 guaranteed by cxacru_cm() */
	len = ret / 4;
	for (offb = 0; offb < len; ) {
		int l = le32_to_cpu(buf[offb++]);
		if (l > stride || l > (len - offb) / 2) {
			dbg("wrong data length %#x in response", l);
			ret = -EIO;
			goto cleanup;
		}
		while (l--) {
			offd = le32_to_cpu(buf[offb++]);
			if (offd >= size) {
				dbg("wrong index %#x in response", offd);
				ret = -EIO;
				goto cleanup;
			}
			data[offd] = le32_to_cpu(buf[offb++]);
		}
	}

	ret = 0;

cleanup:
	kfree(buf);
	return ret;
}

static int cxacru_card_status(struct cxacru_data *instance)
{
	int ret = cxacru_cm(instance, CM_REQUEST_CARD_GET_STATUS, NULL, 0, NULL, 0);
	if (ret < 0) {		/* firmware not loaded */
		dbg("cxacru_adsl_start: CARD_GET_STATUS returned %d", ret);
		return ret;
	}
	return 0;
}

static void cxacru_poll_status(struct cxacru_data *instance);

static int cxacru_atm_start(struct usbatm_data *usbatm_instance,
		struct atm_dev *atm_dev)
{
	struct cxacru_data *instance = usbatm_instance->driver_data;
	struct device *dev = &usbatm_instance->usb_intf->dev;
	/*
	struct atm_dev *atm_dev = usbatm_instance->atm_dev;
	*/
	int ret;

	dbg("cxacru_atm_start");

	/* Read MAC address */
	ret = cxacru_cm(instance, CM_REQUEST_CARD_GET_MAC_ADDRESS, NULL, 0,
			atm_dev->esi, sizeof(atm_dev->esi));
	if (ret < 0) {
		dev_err(dev, "cxacru_atm_start: CARD_GET_MAC_ADDRESS returned %d\n", ret);
		return ret;
	}

	/* start ADSL */
	ret = cxacru_cm(instance, CM_REQUEST_CHIP_ADSL_LINE_START, NULL, 0, NULL, 0);
	if (ret < 0) {
		dev_err(dev, "cxacru_atm_start: CHIP_ADSL_LINE_START returned %d\n", ret);
		return ret;
	}

	/* Start status polling */
	cxacru_poll_status(instance);
	return 0;
}

static void cxacru_poll_status(struct cxacru_data *instance)
{
	u32 buf[CXINF_MAX] = {};
	struct device *dev = &instance->usbatm->usb_intf->dev;
	struct atm_dev *atm_dev = instance->usbatm->atm_dev;
	int ret;

	ret = cxacru_cm_get_array(instance, CM_REQUEST_CARD_INFO_GET, buf, CXINF_MAX);
	if (ret < 0) {
		dev_warn(dev, "poll status: error %d\n", ret);
		goto reschedule;
	}

	if (instance->line_status == buf[CXINF_LINE_STATUS])
		goto reschedule;

	instance->line_status = buf[CXINF_LINE_STATUS];
	switch (instance->line_status) {
	case 0:
		atm_dev->signal = ATM_PHY_SIG_LOST;
		dev_info(dev, "ADSL line: down\n");
		break;

	case 1:
		atm_dev->signal = ATM_PHY_SIG_LOST;
		dev_info(dev, "ADSL line: attemtping to activate\n");
		break;

	case 2:
		atm_dev->signal = ATM_PHY_SIG_LOST;
		dev_info(dev, "ADSL line: training\n");
		break;

	case 3:
		atm_dev->signal = ATM_PHY_SIG_LOST;
		dev_info(dev, "ADSL line: channel analysis\n");
		break;

	case 4:
		atm_dev->signal = ATM_PHY_SIG_LOST;
		dev_info(dev, "ADSL line: exchange\n");
		break;

	case 5:
		atm_dev->link_rate = buf[CXINF_DOWNSTREAM_RATE] * 1000 / 424;
		atm_dev->signal = ATM_PHY_SIG_FOUND;

		dev_info(dev, "ADSL line: up (%d kb/s down | %d kb/s up)\n",
		     buf[CXINF_DOWNSTREAM_RATE], buf[CXINF_UPSTREAM_RATE]);
		break;

	case 6:
		atm_dev->signal = ATM_PHY_SIG_LOST;
		dev_info(dev, "ADSL line: waiting\n");
		break;

	case 7:
		atm_dev->signal = ATM_PHY_SIG_LOST;