path: root/drivers/net/wireless/libertas/if_sdio.c

/*
 *  linux/drivers/net/wireless/libertas/if_sdio.c
 *
 *  Copyright 2007-2008 Pierre Ossman
 *
 * Inspired by if_cs.c, Copyright 2007 Holger Schurig
 *
 * 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 hardware has more or less no CMD53 support, so all registers
 * must be accessed using sdio_readb()/sdio_writeb().
 *
 * Transfers must be in one transaction or the firmware goes bonkers.
 * This means that the transfer must either be small enough to do a
 * byte based transfer or it must be padded to a multiple of the
 * current block size.
 *
 * As SDIO is still new to the kernel, it is unfortunately common with
 * bugs in the host controllers related to that. One such bug is that
 * controllers cannot do transfers that aren't a multiple of 4 bytes.
 * If you don't have time to fix the host controller driver, you can
 * work around the problem by modifying if_sdio_host_to_card() and
 * if_sdio_card_to_host() to pad the data.
 */

#include <linux/kernel.h>
#include <linux/moduleparam.h>
#include <linux/firmware.h>
#include <linux/netdevice.h>
#include <linux/delay.h>
#include <linux/mmc/card.h>
#include <linux/mmc/sdio_func.h>
#include <linux/mmc/sdio_ids.h>

#include "host.h"
#include "decl.h"
#include "defs.h"
#include "dev.h"
#include "if_sdio.h"

static char *lbs_helper_name = NULL;
module_param_named(helper_name, lbs_helper_name, charp, 0644);

static char *lbs_fw_name = NULL;
module_param_named(fw_name, lbs_fw_name, charp, 0644);

static const struct sdio_device_id if_sdio_ids[] = {
	{ SDIO_DEVICE(SDIO_VENDOR_ID_MARVELL, SDIO_DEVICE_ID_MARVELL_LIBERTAS) },
	{ /* end: all zeroes */						},
};

MODULE_DEVICE_TABLE(sdio, if_sdio_ids);

struct if_sdio_model {
	int model;
	const char *helper;
	const char *firmware;
};

static struct if_sdio_model if_sdio_models[] = {
	{
		/* 8385 */
		.model = 0x04,
		.helper = "sd8385_helper.bin",
		.firmware = "sd8385.bin",
	},
	{
		/* 8686 */
		.model = 0x0B,
		.helper = "sd8686_helper.bin",
		.firmware = "sd8686.bin",
	},
};

struct if_sdio_packet {
	struct if_sdio_packet	*next;
	u16			nb;
	u8			buffer[0] __attribute__((aligned(4)));
};

struct if_sdio_card {
	struct sdio_func	*func;
	struct lbs_private	*priv;

	int			model;
	unsigned long		ioport;

	const char		*helper;
	const char		*firmware;

	u8			buffer[65536];

	spinlock_t		lock;
	struct if_sdio_packet	*packets;
	struct work_struct	packet_worker;
};

/********************************************************************/
/* I/O                                                              */
/********************************************************************/

static u16 if_sdio_read_scratch(struct if_sdio_card *card, int *err)
{
	int ret, reg;
	u16 scratch;

	if (card->model == 0x04)
		reg = IF_SDIO_SCRATCH_OLD;
	else
		reg = IF_SDIO_SCRATCH;

	scratch = sdio_readb(card->func, reg, &ret);
	if (!ret)
		scratch |= sdio_readb(card->func, reg + 1, &ret) << 8;

	if (err)
		*err = ret;

	if (ret)
		return 0xffff;

	return scratch;
}

static int if_sdio_handle_cmd(struct if_sdio_card *card,
		u8 *buffer, unsigned size)
{
	struct lbs_private *priv = card->priv;
	int ret;
	unsigned long flags;
	u8 i;

	lbs_deb_enter(LBS_DEB_SDIO);

	if (size > LBS_CMD_BUFFER_SIZE) {
		lbs_deb_sdio("response packet too large (%d bytes)\n",
			(int)size);
		ret = -E2BIG;
		goto out;
	}

	spin_lock_irqsave(&priv->driver_lock, flags);

	i = (priv->resp_idx == 0) ? 1 : 0;
	BUG_ON(priv->resp_len[i]);
	priv->resp_len[i] = size;
	memcpy(priv->resp_buf[i], buffer, size);
	lbs_notify_command_response(priv, i);

	spin_unlock_irqrestore(&card->priv->driver_lock, flags);

	ret = 0;

out:
	lbs_deb_leave_args(LBS_DEB_SDIO, "ret %d", ret);
	return ret;
}

static int if_sdio_handle_data(struct if_sdio_card *card,
		u8 *buffer, unsigned size)
{
	int ret;
	struct