text: /*
   *  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.
   */
  
  #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  
  #include <linux/kernel.h>
  #include <linux/module.h>
  #include <linux/slab.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 <linux/mmc/sdio.h>
  #include <linux/mmc/host.h>
  #include <linux/pm_runtime.h>
  
  #include "host.h"
  #include "decl.h"
  #include "defs.h"
  #include "dev.h"
  #include "cmd.h"
  #include "if_sdio.h"
  
  static void if_sdio_interrupt(struct sdio_func *func);
  
  /* The if_sdio_remove() callback function is called when
   * user removes this module from kernel space or ejects
   * the card from the slot. The driver handles these 2 cases
   * differently for SD8688 combo chip.
   * If the user is removing the module, the FUNC_SHUTDOWN
   * command for SD8688 is sent to the firmware.
   * If the card is removed, there is no need to send this command.
   *
   * The variable 'user_rmmod' is used to distinguish these two
   * scenarios. This flag is initialized as FALSE in case the card
   * is removed, and will be set to TRUE for module removal when
   * module_exit function is called.
   */
  static u8 user_rmmod;
  
  static const struct sdio_device_id if_sdio_ids[] = {
  	{ SDIO_DEVICE(SDIO_VENDOR_ID_MARVELL,
  			SDIO_DEVICE_ID_MARVELL_LIBERTAS) },
  	{ SDIO_DEVICE(SDIO_VENDOR_ID_MARVELL,
  			SDIO_DEVICE_ID_MARVELL_8688WLAN) },
  	{ /* end: all zeroes */				},
  };
  
  MODULE_DEVICE_TABLE(sdio, if_sdio_ids);
  
  #define MODEL_8385	0x04
  #define MODEL_8686	0x0b
  #define MODEL_8688	0x10
  
  static const struct lbs_fw_table fw_table[] = {
  	{ MODEL_8385, "libertas/sd8385_helper.bin", "libertas/sd8385.bin" },
  	{ MODEL_8385, "sd8385_helper.bin", "sd8385.bin" },
  	{ MODEL_8686, "libertas/sd8686_v9_helper.bin", "libertas/sd8686_v9.bin" },
  	{ MODEL_8686, "libertas/sd8686_v8_helper.bin", "libertas/sd8686_v8.bin" },
  	{ MODEL_8686, "sd8686_helper.bin", "sd8686.bin" },
  	{ MODEL_8688, "libertas/sd8688_helper.bin", "libertas/sd8688.bin" },
  	{ MODEL_8688, "sd8688_helper.bin", "sd8688.bin" },
  	{ 0, NULL, NULL }
  };
  MODULE_FIRMWARE("libertas/sd8385_helper.bin");
  MODULE_FIRMWARE("libertas/sd8385.bin");
  MODULE_FIRMWARE("sd8385_helper.bin");
  MODULE_FIRMWARE("sd8385.bin");
  MODULE_FIRMWARE("libertas/sd8686_v9_helper.bin");
  MODULE_FIRMWARE("libertas/sd8686_v9.bin");
  MODULE_FIRMWARE("libertas/sd8686_v8_helper.bin");
  MODULE_FIRMWARE("libertas/sd8686_v8.bin");
  MODULE_FIRMWARE("sd8686_helper.bin");
  MODULE_FIRMWARE("sd8686.bin");
  MODULE_FIRMWARE("libertas/sd8688_helper.bin");
  MODULE_FIRMWARE("libertas/sd8688.bin");
  MODULE_FIRMWARE("sd8688_helper.bin");
  MODULE_FIRMWARE("sd8688.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;
  	unsigned int		scratch_reg;
  	bool			started;
  	wait_queue_head_t	pwron_waitq;
  
  	u8			buffer[65536] __attribute__((aligned(4)));
  
  	spinlock_t		lock;
  	struct if_sdio_packet	*packets;
  
  	struct workqueue_struct	*workqueue;
  	struct work_struct	packet_worker;
  
  	u8			rx_unit;
  };
  
  static void if_sdio_finish_power_on(struct if_sdio_card *card);
  static int if_sdio_power_off(struct if_sdio_card *card);
  
  /********************************************************************/
  /* I/O                                                              */
  /********************************************************************/
  
  /*
   *  For SD8385/SD8686, this function reads firmware status after
   *  the image is downloaded, or reads RX packet length when
   *  interrupt (with IF_SDIO_H_INT_UPLD bit set) is received.
   *  For SD8688, this function reads firmware status only.
   */
  static u16 if_sdio_read_scratch(struct if_sdio_card *card, int *err)
  {
  	int ret;
  	u16 scratch;
  
  	scratch = sdio_readb(card->func, card->scratch_reg, &ret);
  	if (!ret)
  		scratch |= sdio_readb(card->func, card->scratch_reg + 1,
  					&ret) << 8;
  
  	if (err)
  		*err = ret;
  
  	if (ret)
  		return 0xffff;
  
  	return scratch;
  }
  
  static u8 if_sdio_read_rx_unit(struct if_sdio_card *card)
  {
  	int ret;
  	u8 rx_unit;
  
  	rx_unit = sdio_readb(card->func, IF_SDIO_RX_UNIT, &ret);
  
  	if (ret)
  		rx_unit = 0;
  
  	return rx_unit;
  }
  
  static u16 if_sdio_read_rx_len(struct if_sdio_card *card, int *err)
  {
  	int ret;
  	u16 rx_len;
  
  	switch (card->model) {
  	case MODEL_8385:
  	case MODEL_8686:
  		rx_len = if_sdio_read_scratch(card, &ret);
  		break;
  	case MODEL_8688:
  	default: /* for newer chipsets */
  		rx_len = sdio_readb(card->func, IF_SDIO_RX_LEN, &ret);
  		if (!ret)
  			rx_len <<= card->rx_unit;
  		else
  			rx_len = 0xffff;	/* invalid length */
  
  		break;
  	}
  
  	if (err)
  		*err = ret;
  
  	return rx_len;
  }
  
  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(&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 sk_buff *skb;
  	char *data;
  
  	lbs_deb_enter(LBS_DEB_SDIO);
  
  	if (size > MRVDRV_ETH_RX_PACKET_BUFFER_SIZE) {
  		lbs_deb_sdio("response packet too large (%d bytes)\n",
  			(int)size);
  		ret = -E2BIG;
  		goto out;
  	}
  
  	skb = dev_alloc_skb(MRVDRV_ETH_RX_PACKET_BUFFER_SIZE + NET_IP_ALIGN);
  	if (!skb) {
  		ret = -ENOMEM;
  		goto out;
  	}
  
  	skb_reserve(skb, NET_IP_ALIGN);
  
  	data = skb_put(skb, size);
  
  	memcpy(data, buffer, size);
  
  	lbs_process_rxed_packet(card->priv, skb);
  
  	ret = 0;
  
  out:
  	lbs_deb_leave_args(LBS_DEB_SDIO, "ret %d", ret);
  
  	return ret;
  }
  
  static int if_sdio_handle_event(struct if_sdio_card *card,
  		u8 *buffer, unsigned size)
  {
  	int ret;
  	u32 event;
  
  	lbs_deb_enter(LBS_DEB_SDIO);
  
  	if (card->model == MODEL_8385) {
  		event = sdio_readb(card->func, IF_SDIO_EVENT, &ret);
  		if (ret)
  			goto out;
  
  		/* right shift 3 bits to get the event id */
  		event >>= 3;
  	} else {
  		if (size < 4) {
  			lbs_deb_sdio("event packet too small (%d bytes)\n",
  				(int)size);
  			ret = -EINVAL;
  			goto out;
  		}
  		event = buffer[3] << 24;
  		event |= buffer[2] << 16;
  		event |= buffer[1] << 8;
  		event |= buffer[0] << 0;
  	}
  
  	lbs_queue_event(card->priv, event & 0xFF);
  	ret = 0;
  
  out:
  	lbs_deb_leave_args(LBS_DEB_SDIO, "ret %d", ret);
  
  	return ret;
  }
  
  static int if_sdio_wait_status(struct if_sdio_card *card, const u8 condition)
  {
  	u8 status;
  	unsigned long timeout;
  	int ret = 0;
  
  	timeout = jiffies + HZ;
  	while (1) {
  		status = sdio_readb(card->func, IF_SDIO_STATUS, &ret);
  		if (ret)
  			return ret;
  		if ((status & condition) == condition)
  			break;
  		if (time_after(jiffies, timeout))
  			return -ETIMEDOUT;
  		mdelay(1);
  	}
  	return ret;
  }
  
  static int if_sdio_card_to_host(struct if_sdio_card *card)
  {
  	int ret;
  	u16 size, type, chunk;
  
  	lbs_deb_enter(LBS_DEB_SDIO);
  
  	size = if_sdio_read_rx_len(card, &ret);
  	if (ret)
  		goto out;
  
  	if (size < 4) {
  		lbs_deb_sdio("invalid packet size (%d bytes) from firmware\n",
  			(int)size);
  		ret = -EINVAL;
  		goto out;
  	}
  
  	ret = if_sdio_wait_status(card, IF_SDIO_IO_RDY);
  	if (ret)
  		goto out;
  
  	/*
  	 * The transfer must be in one transaction or the firmware
  	 * goes suicidal. There's no way to guarantee that for all
  	 * controllers, but we can at least try.
  	 */
  	chunk = sdio_align_size(card->func, size);
  
  	ret = sdio_readsb(card->func, card->buffer, card->ioport, chunk);
  	if (ret)
  		goto out;
  
  	chunk = card->buffer[0] | (card->buffer[1] << 8);
  	type = card->buffer[2] | (card->buffer[3] << 8);
  
  	lbs_deb_sdio("packet of type %d and size %d bytes\n",
  		(int)type, (int)chunk);
  
  	if (chunk > size) {
  		lbs_deb_sdio("packet fragment (%d > %d)\n",
  			(int)chunk, (int)size);
  		ret = -EINVAL;
  		goto out;
  	}
  
  	if (chunk < size) {
  		lbs_deb_sdio("packet fragment (%d < %d)\n",
  			(int)chunk, (int)size);
  	}
  
  	switch (type) {
  	case MVMS_CMD:
  		ret = if_sdio_handle_cmd(card, card->buffer + 4, chunk - 4);
  		if (ret)
  			goto out;
  		break;
  	case MVMS_DAT:
  		ret = if_sdio_handle_data(card, card->buffer + 4, chunk - 4);
  		if (ret)
  			goto out;
  		break;
  	case MVMS_EVENT:
  		ret = if_sdio_handle_event(card, card->buffer + 4, chunk - 4);
  		if (ret)
  			goto out;
  		break;
  	default:
  		lbs_deb_sdio("invalid type (%d) from firmware\n",
  				(int)type);
  		ret = -EINVAL;
  		goto out;
  	}
  
  out:
  	if (ret)
  		pr_err("problem fetching packet from firmware\n");
  
  	lbs_deb_leave_args(LBS_DEB_SDIO, "ret %d", ret);
  
  	return ret;
  }
  
  static void if_sdio_host_to_card_worker(struct work_struct *work)
  {
  	struct if_sdio_card *card;
  	struct if_sdio_packet *packet;
  	int ret;
  	unsigned long flags;
  
  	lbs_deb_enter(LBS_DEB_SDIO);
  
  	card = container_of(work, struct if_sdio_card, packet_worker);
  
  	while (1) {
  		spin_lock_irqsave(&card->lock, flags);
  		packet = card->packets;
  		if (packet)
  			card->packets = packet->next;
  		spin_unlock_irqrestore(&card->lock, flags);
  
  		if (!packet)
  			break;
  
  		sdio_claim_host(card->func);
  
  		ret = if_sdio_wait_status(card, IF_SDIO_IO_RDY);
  		if (ret == 0) {
  			ret = sdio_writesb(card->func, card->ioport,
  					   packet->buffer, packet->nb);
  		}
  
  		if (ret)
  			pr_err("error %d sending packet to firmware\n", ret);
  
  		sdio_release_host(card->func);
  
  		kfree(packet);
  	}
  
  	lbs_deb_leave(LBS_DEB_SDIO);
  }
  
  /********************************************************************/
  /* Firmware                                                         */
  /********************************************************************/
  
  #define FW_DL_READY_STATUS (IF_SDIO_IO_RDY | IF_SDIO_DL_RDY)
  
  static int if_sdio_prog_helper(struct if_sdio_card *card,
  				const struct firmware *fw)
  {
  	int ret;
  	unsigned long timeout;
  	u8 *chunk_buffer;
  	u32 chunk_size;
  	const u8 *firmware;
  	size_t size;
  
  	lbs_deb_enter(LBS_DEB_SDIO);
  
  	chunk_buffer = kzalloc(64, GFP_KERNEL);
  	if (!chunk_buffer) {
  		ret = -ENOMEM;
  		goto out;
  	}
  
  	sdio_claim_host(card->func);
  
  	ret = sdio_set_block_size(card->func, 32);
  	if (ret)
  		goto release;
  
  	firmware = fw->data;
  	size = fw->size;
  
  	while (size) {
  		ret = if_sdio_wait_status(card, FW_DL_READY_STATUS);
  		if (ret)
  			goto release;
  
  		/* On some platforms (like Davinci) the chip needs more time
  		 * between helper blocks.
  		 */
  		mdelay(2);
  
  		chunk_size = min_t(size_t, size, 60);
  
  		*((__le32*)chunk_buffer) = cpu_to_le32(chunk_size);
  		memcpy(chunk_buffer + 4, firmware, chunk_size);
  /*
  		lbs_deb_sdio("sending %d bytes chunk\n", chunk_size);
  */
  		ret = sdio_writesb(card->func, card->ioport,
  				chunk_buffer, 64);
  		if (ret)
  			goto release;
  
  		firmware += chunk_size;
  		size -= chunk_size;
  	}
  
  	/* an empty block marks the end of the transfer */
  	memset(chunk_buffer, 0, 4);
  	ret = sdio_writesb(card->func, card->ioport, chunk_buffer, 64);
  	if (ret)
  		goto release;
  
  	lbs_deb_sdio("waiting for helper to boot...\n");
  
  	/* wait for the helper to boot by looking at the size register */
  	timeout = jiffies + HZ;
  	while (1) {
  		u16 req_size;
  
  		req_size = sdio_readb(card->func, IF_SDIO_RD_BASE, &ret);
  		if (ret)
  			goto release;
  
  		req_size |= sdio_readb(card->func, IF_SDIO_RD_BASE + 1, &ret) << 8;
  		if (ret)
  			goto release;
  
  		if (req_size != 0)
  			break;
  
  		if (time_after(jiffies, timeout)) {
  			ret = -ETIMEDOUT;
  			goto release;
  		}
  
  		msleep(10);
  	}
  
  	ret = 0;
  
  release:
  	sdio_release_host(card->func);
  	kfree(chunk_buffer);
  
  out:
  	if (ret)
  		pr_err("failed to load helper firmware\n");
  
  	lbs_deb_leave_args(LBS_DEB_SDIO, "ret %d", ret);
  	return ret;
  }
  
  static int if_sdio_prog_real(struct if_sdio_card *card,
  				const struct firmware *fw)
  {
  	int ret;
  	unsigned long timeout;
  	u8 *chunk_buffer;
  	u32 chunk_size;
  	const u8 *firmware;
  	size_t size, req_size;
  
  	lbs_deb_enter(LBS_DEB_SDIO);
  
  	chunk_buffer = kzalloc(512, GFP_KERNEL);
  	if (!chunk_buffer) {
  		ret = -ENOMEM;
  		goto out;
  	}
  
  	sdio_claim_host(card->func);
  
  	ret = sdio_set_block_size(card->func, 32);
  	if (ret)
  		goto release;
  
  	firmware = fw->data;
  	size = fw->size;
  
  	while (size) {
  		timeout = jiffies + HZ;
  		while (1) {
  			ret = if_sdio_wait_status(card, FW_DL_READY_STATUS);
  			if (ret)
  				goto release;
  
  			req_size = sdio_readb(card->func, IF_SDIO_RD_BASE,
  					&ret);
  			if (ret)
  				goto release;
  
  			req_size |= sdio_readb(card->func, IF_SDIO_RD_BASE + 1,
  					&ret) << 8;
  			if (ret)
  				goto release;
  
  			/*
  			 * For SD8688 wait until the length is not 0, 1 or 2
  			 * before downloading the first FW block,
  			 * since BOOT code writes the register to indicate the
  			 * helper/FW download winner,
  			 * the value could be 1 or 2 (Func1 or Func2).
  			 */
  			if ((size != fw->size) || (req_size > 2))
  				break;
  			if (time_after(jiffies, timeout)) {
  				ret = -ETIMEDOUT;
  				goto release;
  			}
  			mdelay(1);
  		}
  
  /*
  		lbs_deb_sdio("firmware wants %d bytes\n", (int)req_size);
  */
  		if (req_size == 0) {
  			lbs_deb_sdio("firmware helper gave up early\n");
  			ret = -EIO;
  			goto release;
  		}
  
  		if (req_size & 0x01) {
  			lbs_deb_sdio("firmware helper signalled error\n");
  			ret = -EIO;
  			goto release;
  		}
  
  		if (req_size > size)
  			req_size = size;
  
  		while (req_size) {
  			chunk_size = min_t(size_t, req_size, 512);
  
  			memcpy(chunk_buffer, firmware, chunk_size);
  /*
  			lbs_deb_sdio("sending %d bytes (%d bytes) chunk\n",
  				chunk_size, (chunk_size + 31) / 32 * 32);
  */
  			ret = sdio_writesb(card->func, card->ioport,
  				chunk_buffer, roundup(chunk_size, 32));
  			if (ret)
  				goto release;
  
  			firmware += chunk_size;
  			size -= chunk_size;
  			req_size -= chunk_size;
  		}
  	}
  
  	ret = 0;
  
  	lbs_deb_sdio("waiting for firmware to boot...\n");
  
  	/* wait for the firmware to boot */
  	timeout = jiffies + HZ;
  	while (1) {
  		u16 scratch;
  
  		scratch = if_sdio_read_scratch(card, &ret);
  		if (ret)
  			goto release;
  
  		if (scratch == IF_SDIO_FIRMWARE_OK)
  			break;
  
  		if (time_after(jiffies, timeout)) {
  			ret = -ETIMEDOUT;
  			goto release;
  		}
  
  		msleep(10);
  	}
  
  	ret = 0;
  
  release:
  	sdio_release_host(card->func);
  	kfree(chunk_buffer);
  
  out:
  	if (ret)
  		pr_err("failed to load firmware\n");
  
  	lbs_deb_leave_args(LBS_DEB_SDIO, "ret %d", ret);
  	return ret;
  }
  
  static void if_sdio_do_prog_firmware(struct lbs_private *priv, int ret,
  				     const struct firmware *helper,
  				     const struct firmware *mainfw)
  {
  	struct if_sdio_card *card = priv->card;
  
  	if (ret) {
  		pr_err("failed to find firmware (%d)\n", ret);
  		return;
  	}
  
  	ret = if_sdio_prog_helper(card, helper);
  	if (ret)
  		return;
  
  	lbs_deb_sdio("Helper firmware loaded\n");
  
  	ret = if_sdio_prog_real(card, mainfw);
  	if (ret)
  		return;
  
  	lbs_deb_sdio("Firmware loaded\n");
  	if_sdio_finish_power_on(card);
  }
  
  static int if_sdio_prog_firmware(struct if_sdio_card *card)
  {
  	int ret;
  	u16 scratch;
  
  	lbs_deb_enter(LBS_DEB_SDIO);
  
  	/*
  	 * Disable interrupts
  	 */
  	sdio_claim_host(card->func);
  	sdio_writeb(card->func, 0x00, IF_SDIO_H_INT_MASK, &ret);
  	sdio_release_host(card->func);
  
  	sdio_claim_host(card->func);
  	scratch = if_sdio_read_scratch(card, &ret);
  	sdio_release_host(card->func);
  
  	lbs_deb_sdio("firmware status = %#x\n", scratch);
  	lbs_deb_sdio("scratch ret = %d\n", ret);
  
  	if (ret)
  		goto out;
  
  
  	/*
  	 * The manual clearly describes that FEDC is the right code to use
  	 * to detect firmware presence, but for SD8686 it is not that simple.
  	 * Scratch is also used to store the RX packet length, so we lose
  	 * the FEDC value early on. So we use a non-zero check in order
  	 * to validate firmware presence.
  	 * Additionally, the SD8686 in the Gumstix always has the high scratch
  	 * bit set, even when the firmware is not loaded. So we have to
  	 * exclude that from the test.
  	 */
  	if (scratch == IF_SDIO_FIRMWARE_OK) {
  		lbs_deb_sdio("firmware already loaded\n");
  		if_sdio_finish_power_on(card);
  		return 0;
  	} else if ((card->model == MODEL_8686) && (scratch & 0x7fff)) {
  		lbs_deb_sdio("firmware may be running\n");
  		if_sdio_finish_power_on(card);
  		return 0;
  	}
  
  	ret = lbs_get_firmware_async(card->priv, &card->func->dev, card->model,
  				     fw_table, if_sdio_do_prog_firmware);
  
  out:
  	lbs_deb_leave_args(LBS_DEB_SDIO, "ret %d", ret);
  	return ret;
  }
  
  /********************************************************************/
  /* Power management                                                 */
  /********************************************************************/
  
  /* Finish power on sequence (after firmware is loaded) */
  static void if_sdio_finish_power_on(struct if_sdio_card *card)
  {
  	struct sdio_func *func = card->func;
  	struct lbs_private *priv = card->priv;
  	int ret;
  
  	sdio_claim_host(func);
  	sdio_set_block_size(card->func, IF_SDIO_BLOCK_SIZE);
  
  	/*
  	 * Get rx_unit if the chip is SD8688 or newer.
  	 * SD8385 & SD8686 do not have rx_unit.
  	 */
  	if ((card->model != MODEL_8385)
  			&& (card->model != MODEL_8686))
  		card->rx_unit = if_sdio_read_rx_unit(card);
  	else
  		card->rx_unit = 0;
  
  	/*
  	 * Set up the interrupt handler late.
  	 *
  	 * If we set it up earlier, the (buggy) hardware generates a spurious
  	 * interrupt, even before the interrupt has been enabled, with
  	 * CCCR_INTx = 0.
  	 *
  	 * We register the interrupt handler late so that we can handle any
  	 * spurious interrupts, and also to avoid generation of that known
  	 * spurious interrupt in the first place.
  	 */
  	ret = sdio_claim_irq(func, if_sdio_interrupt);
  	if (ret)
  		goto release;
  
  	/*
  	 * Enable interrupts now that everything is set up
  	 */
  	sdio_writeb(func, 0x0f, IF_SDIO_H_INT_MASK, &ret);
  	if (ret)
  		goto release_irq;
  
  	sdio_release_host(func);
  
  	/* Set fw_ready before queuing any commands so that
  	 * lbs_thread won't block from sending them to firmware.
  	 */
  	priv->fw_ready = 1;
  
  	/*
  	 * FUNC_INIT is required for SD8688 WLAN/BT multiple functions
  	 */
  	if (card->model == MODEL_8688) {
  		struct cmd_header cmd;
  
  		memset(&cmd, 0, sizeof(cmd));
  
  		lbs_deb_sdio("send function INIT command\n");
  		if (__lbs_cmd(priv, CMD_FUNC_INIT, &cmd, sizeof(cmd),
  				lbs_cmd_copyback, (unsigned long) &cmd))
  			netdev_alert(priv->dev, "CMD_FUNC_INIT cmd failed\n");
  	}
  
  	wake_up(&card->pwron_waitq);
  
  	if (!card->started) {
  		ret = lbs_start_card(priv);
  		if_sdio_power_off(card);
  		if (ret == 0) {
  			card->started = true;
  			/* Tell PM core that we don't need the card to be
  			 * powered now */
  			pm_runtime_put(&func->dev);
  		}
  	}
  
  	return;
  
  release_irq:
  	sdio_release_irq(func);
  release:
  	sdio_release_host(func);
  }
  
  static int if_sdio_power_on(struct if_sdio_card *card)
  {
  	struct sdio_func *func = card->func;
  	struct mmc_host *host = func->card->host;
  	int ret;
  
  	sdio_claim_host(func);
  
  	ret = sdio_enable_func(func);
  	if (ret)
  		goto release;
  
  	/* For 1-bit transfers to the 8686 model, we need to enable the
  	 * interrupt flag in the CCCR register. Set the MMC_QUIRK_LENIENT_FN0
  	 * bit to allow access to non-vendor registers. */
  	if ((card->model == MODEL_8686) &&
  	    (host->caps & MMC_CAP_SDIO_IRQ) &&
  	    (host->ios.bus_width == MMC_BUS_WIDTH_1)) {
  		u8 reg;
  
  		func->card->quirks |= MMC_QUIRK_LENIENT_FN0;
  		reg = sdio_f0_readb(func, SDIO_CCCR_IF, &ret);
  		if (ret)
  			goto disable;
  
  		reg |= SDIO_BUS_ECSI;
  		sdio_f0_writeb(func, reg, SDIO_CCCR_IF, &ret);
  		if (ret)
  			goto disable;
  	}
  
  	card->ioport = sdio_readb(func, IF_SDIO_IOPORT, &ret);
  	if (ret)
  		goto disable;
  
  	card->ioport |= sdio_readb(func, IF_SDIO_IOPORT + 1, &ret) << 8;
  	if (ret)
  		goto disable;
  
  	card->ioport |= sdio_readb(func, IF_SDIO_IOPORT + 2, &ret) << 16;
  	if (ret)
  		goto disable;
  
  	sdio_release_host(func);
  	ret = if_sdio_prog_firmware(card);
  	if (ret) {
  		sdio_claim_host(func);
  		goto disable;
  	}
  
  	return 0;
  
  disable:
  	sdio_disable_func(func);
  release:
  	sdio_release_host(func);
  	return ret;
  }
  
  static int if_sdio_power_off(struct if_sdio_card *card)
  {
  	struct sdio_func *func = card->func;
  	struct lbs_private *priv = card->priv;
  
  	priv->fw_ready = 0;
  
  	sdio_claim_host(func);
  	sdio_release_irq(func);
  	sdio_disable_func(func);
  	sdio_release_host(func);
  	return 0;
  }
  
  
  /*******************************************************************/
  /* Libertas callbacks                                              */
  /*******************************************************************/
  
  static int if_sdio_host_to_card(struct lbs_private *priv,
  		u8 type, u8 *buf, u16 nb)
  {
  	int ret;
  	struct if_sdio_card *card;
  	struct if_sdio_packet *packet, *cur;
  	u16 size;
  	unsigned long flags;
  
  	lbs_deb_enter_args(LBS_DEB_SDIO, "type %d, bytes %d", type, nb);
  
  	card = priv->card;
  
  	if (nb > (65536 - sizeof(struct if_sdio_packet) - 4)) {
  		ret = -EINVAL;
  		goto out;
  	}
  
  	/*
  	 * The transfer must be in one transaction or the firmware
  	 * goes suicidal. There's no way to guarantee that for all
  	 * controllers, but we can at least try.
  	 */
  	size = sdio_align_size(card->func, nb + 4);
  
  	packet = kzalloc(sizeof(struct if_sdio_packet) + size,
  			GFP_ATOMIC);
  	if (!packet) {
  		ret = -ENOMEM;
  		goto out;
  	}
  
  	packet->next = NULL;
  	packet->nb = size;
  
  	/*
  	 * SDIO specific header.
  	 */
  	packet->buffer[0] = (nb + 4) & 0xff;
  	packet->buffer[1] = ((nb + 4) >> 8) & 0xff;
  	packet->buffer[2] = type;
  	packet->buffer[3] = 0;
  
  	memcpy(packet->buffer + 4, buf, nb);
  
  	spin_lock_irqsave(&card->lock, flags);
  
  	if (!card->packets)
  		card->packets = packet;
  	else {
  		cur = card->packets;
  		while (cur->next)
  			cur = cur->next;
  		cur->next = packet;
  	}
  
  	switch (type) {
  	case MVMS_CMD:
  		priv->dnld_sent = DNLD_CMD_SENT;
  		break;
  	case MVMS_DAT:
  		priv->dnld_sent = DNLD_DATA_SENT;
  		break;
  	default:
  		lbs_deb_sdio("unknown packet type %d\n", (int)type);
  	}
  
  	spin_unlock_irqrestore(&card->lock, flags);
  
  	queue_work(card->workqueue, &card->packet_worker);
  
  	ret = 0;
  
  out:
  	lbs_deb_leave_args(LBS_DEB_SDIO, "ret %d", ret);
  
  	return ret;
  }
  
  static int if_sdio_enter_deep_sleep(struct lbs_private *priv)
  {
  	int ret = -1;
  	struct cmd_header cmd;
  
  	memset(&cmd, 0, sizeof(cmd));
  
  	lbs_deb_sdio("send DEEP_SLEEP command\n");
  	ret = __lbs_cmd(priv, CMD_802_11_DEEP_SLEEP, &cmd, sizeof(cmd),
  			lbs_cmd_copyback, (unsigned long) &cmd);
  	if (ret)
  		netdev_err(priv->dev, "DEEP_SLEEP cmd failed\n");
  
  	mdelay(200);
  	return ret;
  }
  
  static int if_sdio_exit_deep_sleep(struct lbs_private *priv)
  {
  	struct if_sdio_card *card = priv->card;
  	int ret = -1;
  
  	lbs_deb_enter(LBS_DEB_SDIO);
  	sdio_claim_host(card->func);
  
  	sdio_writeb(card->func, HOST_POWER_UP, CONFIGURATION_REG, &ret);
  	if (ret)
  		netdev_err(priv->dev, "sdio_writeb failed!\n");
  
  	sdio_release_host(card->func);
  	lbs_deb_leave_args(LBS_DEB_SDIO, "ret %d", ret);
  	return ret;
  }
  
  static int if_sdio_reset_deep_sleep_wakeup(struct lbs_private *priv)
  {
  	struct if_sdio_card *card = priv->card;
  	int ret = -1;
  
  	lbs_deb_enter(LBS_DEB_SDIO);
  	sdio_claim_host(card->func);
  
  	sdio_writeb(card->func, 0, CONFIGURATION_REG, &ret);
  	if (ret)
  		netdev_err(priv->dev, "sdio_writeb failed!\n");
  
  	sdio_release_host(card->func);
  	lbs_deb_leave_args(LBS_DEB_SDIO, "ret %d", ret);
  	return ret;
  
  }
  
  static struct mmc_host *reset_host;
  
  static void if_sdio_reset_card_worker(struct work_struct *work)
  {
  	/*
  	 * The actual reset operation must be run outside of lbs_thread. This
  	 * is because mmc_remove_host() will cause the device to be instantly
  	 * destroyed, and the libertas driver then needs to end lbs_thread,
  	 * leading to a deadlock.
  	 *
  	 * We run it in a workqueue totally independent from the if_sdio_card
  	 * instance for that reason.
  	 */
  
  	pr_info("Resetting card...");
  	mmc_remove_host(reset_host);
  	mmc_add_host(reset_host);
  }
  static DECLARE_WORK(card_reset_work, if_sdio_reset_card_worker);
  
  static void if_sdio_reset_card(struct lbs_private *priv)
  {
  	struct if_sdio_card *card = priv->card;
  
  	if (work_pending(&card_reset_work))
  		return;
  
  	reset_host = card->func->card->host;
  	schedule_work(&card_reset_work);
  }
  
  static int if_sdio_power_save(struct lbs_private *priv)
  {
  	struct if_sdio_card *card = priv->card;
  	int ret;
  
  	flush_workqueue(card->workqueue);
  
  	ret = if_sdio_power_off(card);
  
  	/* Let runtime PM know the card is powered off */
  	pm_runtime_put_sync(&card->func->dev);
  
  	return ret;
  }
  
  static int if_sdio_power_restore(struct lbs_private *priv)
  {
  	struct if_sdio_card *card = priv->card;
  	int r;
  
  	/* Make sure the card will not be powered off by runtime PM */
  	pm_runtime_get_sync(&card->func->dev);
  
  	r = if_sdio_power_on(card);
  	if (r)
  		return r;
  
  	wait_event(card->pwron_waitq, priv->fw_ready);
  	return 0;
  }
  
  
  /*******************************************************************/
  /* SDIO callbacks                                                  */
  /*******************************************************************/
  
  static void if_sdio_interrupt(struct sdio_func *func)
  {
  	int ret;
  	struct if_sdio_card *card;
  	u8 cause;
  
  	lbs_deb_enter(LBS_DEB_SDIO);
  
  	card = sdio_get_drvdata(func);
  
  	cause = sdio_readb(card->func, IF_SDIO_H_INT_STATUS, &ret);
  	if (ret || !cause)
  		goto out;
  
  	lbs_deb_sdio("interrupt: 0x%X\n", (unsigned)cause);
  
  	sdio_writeb(card->func, ~cause, IF_SDIO_H_INT_STATUS, &ret);
  	if (ret)
  		goto out;
  
  	/*
  	 * Ignore the define name, this really means the card has
  	 * successfully received the command.
  	 */
  	card->priv->is_activity_detected = 1;
  	if (cause & IF_SDIO_H_INT_DNLD)
  		lbs_host_to_card_done(card->priv);
  
  
  	if (cause & IF_SDIO_H_INT_UPLD) {
  		ret = if_sdio_card_to_host(card);
  		if (ret)
  			goto out;
  	}
  
  	ret = 0;
  
  out:
  	lbs_deb_leave_args(LBS_DEB_SDIO, "ret %d", ret);
  }
  
  static int if_sdio_probe(struct sdio_func *func,
  		const struct sdio_device_id *id)
  {
  	struct if_sdio_card *card;
  	struct lbs_private *priv;
  	int ret, i;
  	unsigned int model;
  	struct if_sdio_packet *packet;
  
  	lbs_deb_enter(LBS_DEB_SDIO);
  
  	for (i = 0;i < func->card->num_info;i++) {
  		if (sscanf(func->card->info[i],
  				"802.11 SDIO ID: %x", &model) == 1)
  			break;
  		if (sscanf(func->card->info[i],
  				"ID: %x", &model) == 1)
  			break;
  		if (!strcmp(func->card->info[i], "IBIS Wireless SDIO Card")) {
  			model = MODEL_8385;
  			break;
  		}
  	}
  
  	if (i == func->card->num_info) {
  		pr_err("unable to identify card model\n");
  		return -ENODEV;
  	}
  
  	card = kzalloc(sizeof(struct if_sdio_card), GFP_KERNEL);
  	if (!card)
  		return -ENOMEM;
  
  	card->func = func;
  	card->model = model;
  
  	switch (card->model) {
  	case MODEL_8385:
  		card->scratch_reg = IF_SDIO_SCRATCH_OLD;
  		break;
  	case MODEL_8686:
  		card->scratch_reg = IF_SDIO_SCRATCH;
  		break;
  	case MODEL_8688:
  	default: /* for newer chipsets */
  		card->scratch_reg = IF_SDIO_FW_STATUS;
  		break;
  	}
  
  	spin_lock_init(&card->lock);
  	card->workqueue = alloc_workqueue("libertas_sdio", WQ_MEM_RECLAIM, 0);
  	if (unlikely(!card->workqueue)) {
  		ret = -ENOMEM;
  		goto err_queue;
  	}
  	INIT_WORK(&card->packet_worker, if_sdio_host_to_card_worker);
  	init_waitqueue_head(&card->pwron_waitq);
  
  	/* Check if we support this card */
  	for (i = 0; i < ARRAY_SIZE(fw_table); i++) {
  		if (card->model == fw_table[i].model)
  			break;
  	}
  	if (i == ARRAY_SIZE(fw_table)) {
  		pr_err("unknown card model 0x%x\n", card->model);
  		ret = -ENODEV;
  		goto free;
  	}
  
  	sdio_set_drvdata(func, card);
  
  	lbs_deb_sdio("class = 0x%X, vendor = 0x%X, "
  			"device = 0x%X, model = 0x%X, ioport = 0x%X\n",
  			func->class, func->vendor, func->device,
  			model, (unsigned)card->ioport);
  
  
  	priv = lbs_add_card(card, &func->dev);
  	if (!priv) {
  		ret = -ENOMEM;
  		goto free;
  	}
  
  	card->priv = priv;
  
  	priv->card = card;
  	priv->hw_host_to_card = if_sdio_host_to_card;
  	priv->enter_deep_sleep = if_sdio_enter_deep_sleep;
  	priv->exit_deep_sleep = if_sdio_exit_deep_sleep;
  	priv->reset_deep_sleep_wakeup = if_sdio_reset_deep_sleep_wakeup;
  	priv->reset_card = if_sdio_reset_card;
  	priv->power_save = if_sdio_power_save;
  	priv->power_restore = if_sdio_power_restore;
  	priv->is_polling = !(func->card->host->caps & MMC_CAP_SDIO_IRQ);
  	ret = if_sdio_power_on(card);
  	if (ret)
  		goto err_activate_card;
  
  out:
  	lbs_deb_leave_args(LBS_DEB_SDIO, "ret %d", ret);
  
  	return ret;
  
  err_activate_card:
  	flush_workqueue(card->workqueue);
  	lbs_remove_card(priv);
  free:
  	destroy_workqueue(card->workqueue);
  err_queue:
  	while (card->packets) {
  		packet = card->packets;
  		card->packets = card->packets->next;
  		kfree(packet);
  	}
  
  	kfree(card);
  
  	goto out;
  }
  
  static void if_sdio_remove(struct sdio_func *func)
  {
  	struct if_sdio_card *card;
  	struct if_sdio_packet *packet;
  
  	lbs_deb_enter(LBS_DEB_SDIO);
  
  	card = sdio_get_drvdata(func);
  
  	/* Undo decrement done above in if_sdio_probe */
  	pm_runtime_get_noresume(&func->dev);
  
  	if (user_rmmod && (card->model == MODEL_8688)) {
  		/*
  		 * FUNC_SHUTDOWN is required for SD8688 WLAN/BT
  		 * multiple functions
  		 */
  		struct cmd_header cmd;
  
  		memset(&cmd, 0, sizeof(cmd));
  
  		lbs_deb_sdio("send function SHUTDOWN command\n");
  		if (__lbs_cmd(card->priv, CMD_FUNC_SHUTDOWN,
  				&cmd, sizeof(cmd), lbs_cmd_copyback,
  				(unsigned long) &cmd))
  			pr_alert("CMD_FUNC_SHUTDOWN cmd failed\n");
  	}
  
  
  	lbs_deb_sdio("call remove card\n");
  	lbs_stop_card(card->priv);
  	lbs_remove_card(card->priv);
  
  	destroy_workqueue(card->workqueue);
  
  	while (card->packets) {
  		packet = card->packets;
  		card->packets = card->packets->next;
  		kfree(packet);
  	}
  
  	kfree(card);
  	lbs_deb_leave(LBS_DEB_SDIO);
  }
  
  static int if_sdio_suspend(struct device *dev)
  {
  	struct sdio_func *func = dev_to_sdio_func(dev);
  	struct if_sdio_card *card = sdio_get_drvdata(func);
  	struct lbs_private *priv = card->priv;
  	int ret;
  
  	mmc_pm_flag_t flags = sdio_get_host_pm_caps(func);
  	priv->power_up_on_resume = false;
  
  	/* If we're powered off anyway, just let the mmc layer remove the
  	 * card. */
  	if (!lbs_iface_active(priv)) {
  		if (priv->fw_ready) {
  			priv->power_up_on_resume = true;
  			if_sdio_power_off(card);
  		}
  
  		return 0;
  	}
  
  	dev_info(dev, "%s: suspend: PM flags = 0x%x\n",
  		 sdio_func_id(func), flags);
  
  	/* If we aren't being asked to wake on anything, we should bail out
  	 * and let the SD stack power down the card.
  	 */
  	if (priv->wol_criteria == EHS_REMOVE_WAKEUP) {
  		dev_info(dev, "Suspend without wake params -- powering down card\n");
  		if (priv->fw_ready) {
  			ret = lbs_suspend(priv);
  			if (ret)
  				return ret;
  
  			priv->power_up_on_resume = true;
  			if_sdio_power_off(card);
  		}
  
  		return 0;
  	}
  
  	if (!(flags & MMC_PM_KEEP_POWER)) {
  		dev_err(dev, "%s: cannot remain alive while host is suspended\n",
  			sdio_func_id(func));
  		return -ENOSYS;
  	}
  
  	ret = sdio_set_host_pm_flags(func, MMC_PM_KEEP_POWER);
  	if (ret)
  		return ret;
  
  	ret = lbs_suspend(priv);
  	if (ret)
  		return ret;
  
  	return sdio_set_host_pm_flags(func, MMC_PM_WAKE_SDIO_IRQ);
  }
  
  static int if_sdio_resume(struct device *dev)
  {
  	struct sdio_func *func = dev_to_sdio_func(dev);
  	struct if_sdio_card *card = sdio_get_drvdata(func);
  	int ret;
  
  	dev_info(dev, "%s: resume: we're back\n", sdio_func_id(func));
  
  	if (card->priv->power_up_on_resume) {
  		if_sdio_power_on(card);
  		wait_event(card->pwron_waitq, card->priv->fw_ready);
  	}
  
  	ret = lbs_resume(card->priv);
  
  	return ret;
  }
  
  static const struct dev_pm_ops if_sdio_pm_ops = {
  	.suspend	= if_sdio_suspend,
  	.resume		= if_sdio_resume,
  };
  
  static struct sdio_driver if_sdio_driver = {
  	.name		= "libertas_sdio",
  	.id_table	= if_sdio_ids,
  	.probe		= if_sdio_probe,
  	.remove		= if_sdio_remove,
  	.drv = {
  		.pm = &if_sdio_pm_ops,
  	},
  };
  
  /*******************************************************************/
  /* Module functions                                                */
  /*******************************************************************/
  
  static int __init if_sdio_init_module(void)
  {
  	int ret = 0;
  
  	lbs_deb_enter(LBS_DEB_SDIO);
  
  	printk(KERN_INFO "libertas_sdio: Libertas SDIO driver\n");
  	printk(KERN_INFO "libertas_sdio: Copyright Pierre Ossman\n");
  
  	ret = sdio_register_driver(&if_sdio_driver);
  
  	/* Clear the flag in case user removes the card. */
  	user_rmmod = 0;
  
  	lbs_deb_leave_args(LBS_DEB_SDIO, "ret %d", ret);
  
  	return ret;
  }
  
  static void __exit if_sdio_exit_module(void)
  {
  	lbs_deb_enter(LBS_DEB_SDIO);
  
  	/* Set the flag as user is removing this module. */
  	user_rmmod = 1;
  
  	cancel_work_sync(&card_reset_work);
  
  	sdio_unregister_driver(&if_sdio_driver);
  
  	lbs_deb_leave(LBS_DEB_SDIO);
  }
  
  module_init(if_sdio_init_module);
  module_exit(if_sdio_exit_module);
  
  MODULE_DESCRIPTION("Libertas SDIO WLAN Driver");
  MODULE_AUTHOR("Pierre Ossman");
  MODULE_LICENSE("GPL");
  