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/**
 * Copyright (c) 2014 Redpine Signals Inc.
 *
 * Permission to use, copy, modify, and/or distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 *
 */

#include <linux/module.h>
#include "rsi_sdio.h"
#include "rsi_common.h"

/**
 * rsi_sdio_set_cmd52_arg() - This function prepares cmd 52 read/write arg.
 * @rw: Read/write
 * @func: function number
 * @raw: indicates whether to perform read after write
 * @address: address to which to read/write
 * @writedata: data to write
 *
 * Return: argument
 */
static u32 rsi_sdio_set_cmd52_arg(bool rw,
				  u8 func,
				  u8 raw,
				  u32 address,
				  u8 writedata)
{
	return ((rw & 1) << 31) | ((func & 0x7) << 28) |
		((raw & 1) << 27) | (1 << 26) |
		((address & 0x1FFFF) << 9) | (1 << 8) |
		(writedata & 0xFF);
}

/**
 * rsi_cmd52writebyte() - This function issues cmd52 byte write onto the card.
 * @card: Pointer to the mmc_card.
 * @address: Address to write.
 * @byte: Data to write.
 *
 * Return: Write status.
 */
static int rsi_cmd52writebyte(struct mmc_card *card,
			      u32 address,
			      u8 byte)
{
	struct mmc_command io_cmd;
	u32 arg;

	memset(&io_cmd, 0, sizeof(io_cmd));
	arg = rsi_sdio_set_cmd52_arg(1, 0, 0, address, byte);
	io_cmd.opcode = SD_IO_RW_DIRECT;
	io_cmd.arg = arg;
	io_cmd.flags = MMC_RSP_R5 | MMC_CMD_AC;

	return mmc_wait_for_cmd(card->host, &io_cmd, 0);
}

/**
 * rsi_cmd52readbyte() - This function issues cmd52 byte read onto the card.
 * @card: Pointer to the mmc_card.
 * @address: Address to read from.
 * @byte: Variable to store read value.
 *
 * Return: Read status.
 */
static int rsi_cmd52readbyte(struct mmc_card *card,
			     u32 address,
			     u8 *byte)
{
	struct mmc_command io_cmd;
	u32 arg;
	int err;

	memset(&io_cmd, 0, sizeof(io_cmd));
	arg = rsi_sdio_set_cmd52_arg(0, 0, 0, address, 0);
	io_cmd.opcode = SD_IO_RW_DIRECT;
	io_cmd.arg = arg;
	io_cmd.flags = MMC_RSP_R5 | MMC_CMD_AC;

	err = mmc_wait_for_cmd(card->host, &io_cmd, 0);
	if ((!err) && (byte))
		*byte =  io_cmd.resp[0] & 0xFF;
	return err;
}

/**
 * rsi_issue_sdiocommand() - This function issues sdio commands.
 * @func: Pointer to the sdio_func structure.
 * @opcode: Opcode value.
 * @arg: Arguments to pass.
 * @flags: Flags which are set.
 * @resp: Pointer to store response.
 *
 * Return: err: command status as 0 or -1.
 */
static int rsi_issue_sdiocommand(struct sdio_func *func,
				 u32 opcode,
				 u32 arg,
				 u32 flags,
				 u32 *resp)
{
	struct mmc_command cmd;
	struct mmc_host *host;
	int err;

	host = func->card->host;

	memset(&cmd, 0, sizeof(struct mmc_command));
	cmd.opcode = opcode;
	cmd.arg = arg;
	cmd.flags = flags;
	err = mmc_wait_for_cmd(host, &cmd, 3);

	if ((!err) && (resp))
		*resp = cmd.resp[0];

	return err;
}

/**
 * rsi_handle_interrupt() - This function is called upon the occurence
 *			    of an interrupt.
 * @function: Pointer to the sdio_func structure.
 *
 * Return: None.
 */
static void rsi_handle_interrupt(struct sdio_func *function)
{
	struct rsi_hw *adapter = sdio_get_drvdata(function);

	sdio_release_host(function);
	rsi_interrupt_handler(adapter);
	sdio_claim_host(function);
}

/**
 * rsi_reset_card() - This function resets and re-initializes the card.
 * @pfunction: Pointer to the sdio_func structure.
 *
 * Return: None.
 */
static void rsi_reset_card(struct sdio_func *pfunction)
{
	int ret = 0;
	int err;
	struct mmc_card *card = pfunction->card;
	struct mmc_host *host = card->host;
	s32 bit = (fls(host->ocr_avail) - 1);
	u8 cmd52_resp;
	u32 clock, resp, i;
	u16 rca;

	/* Reset 9110 chip */
	ret = rsi_cmd52writebyte(pfunction->card,
				 SDIO_CCCR_ABORT,
				 (1 << 3));

	/* Card will not send any response as it is getting reset immediately
	 * Hence expect a timeout status from host controller
	 */
	if (ret != -ETIMEDOUT)
		rsi_dbg(ERR_ZONE, "%s: Reset failed : %d\n", __func__, ret);

	/* Wait for few milli seconds to get rid of residue charges if any */
	msleep(20);

	/* Initialize the SDIO card */
	host->ios.vdd = bit;
	host->ios.chip_select = MMC_CS_DONTCARE;
	host->ios.bus_mode = MMC_BUSMODE_OPENDRAIN;
	host->ios.power_mode = MMC_POWER_UP;
	host->ios.bus_width = MMC_BUS_WIDTH_1;
	host->ios.timing = MMC_TIMING_LEGACY;
	host->ops->set_ios(host, &host->ios);

	/*
	 * This delay should be sufficient to allow the power supply
	 * to reach the minimum voltage.
	 */
	msleep(20);

	host->ios.clock = host->f_min;
	host->ios.power_mode = MMC_POWER_ON;
	host->ops->set_ios(host, &host->ios);

	/*
	 * This delay must be at least 74 clock sizes, or 1 ms, or the
	 * time required to reach a stable voltage.
	 */
	msleep(20);

	/* Issue CMD0. Goto idle state */
	host->ios.chip_select = MMC_CS_HIGH;
	host->ops->set_ios(host, &host->ios);
	msleep(20);
	err = rsi_issue_sdiocommand(pfunction,
				    MMC_GO_IDLE_STATE,
				    0,
				    (MMC_RSP_NONE | MMC_CMD_BC),
				    NULL);
	host->ios.chip_select = MMC_CS_DONTCARE;
	host->ops->set_ios(host, &host->ios);
	msleep(20);
	host->use_spi_crc = 0;

	if (err)
		rsi_dbg(ERR_ZONE, "%s: CMD0 failed : %d\n", __func__, err);

	if (!host->ocr_avail) {
		/* Issue CMD5, arg = 0 */
		err = rsi_issue_sdiocommand(pfunction,
					    SD_IO_SEND_OP_COND,
					    0,
					    (MMC_RSP_R4 | MMC_CMD_BCR),
					    &resp);
		if (err)
			rsi_dbg(ERR_ZONE, "%s: CMD5 failed : %d\n",
				__func__, err);
		host->ocr_avail = resp;
	}

	/* Issue CMD5, arg = ocr. Wait till card is ready  */
	for (i = 0; i < 100; i++) {
		err = rsi_issue_sdiocommand(pfunction,
					    SD_IO_SEND_OP_COND,
					    host->ocr_avail,
					    (MMC_RSP_R4 | MMC_CMD_BCR),
					    &resp);
		if (err) {
			rsi_dbg(ERR_ZONE, "%s: CMD5 failed : %d\n",
				__func__, err);
			break;
		}

		if (resp & MMC_CARD_BUSY)
			break;
		msleep(20);
	}

	if ((i == 100) || (err)) {
		rsi_dbg(ERR_ZONE, "%s: card in not ready : %d %d\n",
			__func__, i, err);
		return;
	}

	/* Issue CMD3, get RCA */
	err = rsi_issue_sdiocommand(pfunction,
				    SD_SEND_RELATIVE_ADDR,
				    0,
				    (MMC_RSP_R6 | MMC_CMD_BCR),
				    &resp);
	if (err) {
		rsi_dbg(ERR_ZONE, "%s: CMD3 failed : %d\n", __func__, err);
		return;
	}
	rca = resp >> 16;
	host->ios.bus_mode = MMC_BUSMODE_PUSHPULL;
	host->ops->set_ios(host, &host->ios);

	/* Issue CMD7, select card  */
	err = rsi_issue_sdiocommand(pfunction,
				    MMC_SELECT_CARD,
				    (rca << 16),
				    (MMC_RSP_R1 | MMC_CMD_AC),
				    NULL);
	if (err) {
		rsi_dbg(ERR_ZONE, "%s: CMD7 failed : %d\n", __func__, err);
		return;
	}

	/* Enable high speed */
	if (card->host->caps & MMC_CAP_SD_HIGHSPEED) {
		rsi_dbg(ERR_ZONE, "%s: Set high speed mode\n", __func__);
		err = rsi_cmd52readbyte(card, SDIO_CCCR_SPEED, &cmd52_resp);
		if (err) {
			rsi_dbg(ERR_ZONE, "%s: CCCR speed reg read failed: %d\n",
				__func__, err);
		} else {
			err = rsi_cmd52writebyte(card,
						 SDIO_CCCR_SPEED,
						 (cmd52_resp | SDIO_SPEED_EHS));
			if (err) {
				rsi_dbg(ERR_ZONE,
					"%s: CCR speed regwrite failed %d\n",
					__func__, err);
				return;
			}
			host->ios.timing = MMC_TIMING_SD_HS;
			host->ops->set_ios(host, &host->ios);
		}
	}

	/* Set clock */
	if (mmc_card_hs(card))
		clock = 50000000;
	else
		clock = card->cis.max_dtr;

	if (clock > host->f_max)
		clock = host->f_max;

	host->ios.clock = clock;
	host->ops->set_ios(host, &host->ios);

	if (card->host->caps & MMC_CAP_4_BIT_DATA) {
		/* CMD52: Set bus width & disable card detect resistor */
		err = rsi_cmd52writebyte(card,
					 SDIO_CCCR_IF,
					 (SDIO_BUS_CD_DISABLE |
					  SDIO_BUS_WIDTH_4BIT));
		if (err) {
			rsi_dbg(ERR_ZONE, "%s: Set bus mode failed : %d\n",
				__func__, err);
			return;
		}
		host->ios.bus_width = MMC_BUS_WIDTH_4;
		host->ops->set_ios(host, &host->ios);
	}
}

/**
 * rsi_setclock() - This function sets the clock frequency.
 * @adapter: Pointer to the adapter structure.
 * @freq: Clock frequency.
 *
 * Return: None.
 */
static void rsi_setclock(struct rsi_hw *adapter, u32 freq)
{
	struct rsi_91x_sdiodev *dev =
		(struct rsi_91x_sdiodev *)adapter->rsi_dev;
	struct mmc_host *host = dev->pfunction->card->host;
	u32 clock;

	clock = freq * 1000;
	if (clock > host->f_max)
		clock = host->f_max;
	host->ios.clock = clock;
	host->ops->set_ios(host, &host->ios);
}

/**
 * rsi_setblocklength() - This function sets the host block length.
 * @adapter: Pointer to the adapter structure.
 * @length: Block length to be set.
 *
 * Return: status: 0 on success, -1 on failure.
 */
static int rsi_setblocklength(struct rsi_hw *adapter, u32 length)
{
	struct rsi_91x_sdiodev *dev =
		(struct rsi_91x_sdiodev *)adapter->rsi_dev;
	int status;
	rsi_dbg(INIT_ZONE, "%s: Setting the block length\n", __func__);

	status = sdio_set_block_size(dev->pfunction, length);
	dev->pfunction->max_blksize = 256;

	rsi_dbg(INFO_ZONE,
		"%s: Operational blk length is %d\n", __func__, length);
	return status;
}

/**
 * rsi_setupcard() - This function queries and sets the card's features.
 * @adapter: Pointer to the adapter structure.
 *
 * Return: status: 0 on success, -1 on failure.
 */
static int rsi_setupcard(struct rsi_hw *adapter)
{
	struct rsi_91x_sdiodev *dev =
		(struct rsi_91x_sdiodev *)adapter->rsi_dev;
	int status = 0;

	rsi_setclock(adapter, 50000);

	dev->tx_blk_size = 256;
	status = rsi_setblocklength(adapter, dev->tx_blk_size);
	if (status)
		rsi_dbg(ERR_ZONE,
			"%s: Unable to set block length\n", __func__);
	return status;
}

/**
 * rsi_sdio_read_register() - This function reads one byte of information
 *			      from a register.
 * @adapter: Pointer to the adapter structure.
 * @addr: Address of the register.
 * @data: Pointer to the data that stores the data read.
 *
 * Return: 0 on success, -1 on failure.
 */
int rsi_sdio_read_register(struct rsi_hw *adapter,
			   u32 addr,
			   u8 *data)
{
	struct rsi_91x_sdiodev *dev =
		(struct rsi_91x_sdiodev *)adapter->rsi_dev;
	u8 fun_num = 0;
	int status;

	sdio_claim_host(dev->pfunction);

	if (fun_num == 0)
		*data = sdio_f0_readb(dev->pfunction, addr, &status);
	else
		*data = sdio_readb(dev->pfunction, addr, &status);

	sdio_release_host(dev->pfunction);

	return status;
}

/**
 * rsi_sdio_write_register() - This function writes one byte of information
 *			       into a register.
 * @adapter: Pointer to the adapter structure.
 * @function: Function Number.
 * @addr: Address of the register.
 * @data: Pointer to the data tha has to be written.
 *
 * Return: 0 on success, -1 on failure.
 */
int rsi_sdio_write_register(struct rsi_hw *adapter,
			    u8 function,
			    u32 addr,
			    u8 *data)
{
	struct rsi_91x_sdiodev *dev =
		(struct rsi_91x_sdiodev *)adapter->rsi_dev;
	int status = 0;

	sdio_claim_host(dev->pfunction);

	if (function == 0)
		sdio_f0_writeb(dev->pfunction, *data, addr, &status);
	else
		sdio_writeb(dev->pfunction, *data, addr, &status);

	sdio_release_host(dev->pfunction);

	return status;
}

/**
 * rsi_sdio_ack_intr() - This function acks the interrupt received.
 * @adapter: Pointer to the adapter structure.
 * @int_bit: Interrupt bit to write into register.
 *
 * Return: None.
 */
void rsi_sdio_ack_intr(struct rsi_hw *adapter, u8 int_bit)
{
	int status;
	status = rsi_sdio_write_register(adapter,
					 1,
					 (SDIO_FUN1_INTR_CLR_REG |
					  RSI_SD_REQUEST_MASTER),
					 &int_bit);
	if (status)
		rsi_dbg(ERR_ZONE, "%s: unable to send ack\n", __func__);
}



/**
 * rsi_sdio_read_register_multiple() - This function read multiple bytes of
 *				       information from the SD card.
 * @adapter: Pointer to the adapter structure.
 * @addr: Address of the register.
 * @count: Number of multiple bytes to be read.
 * @data: Pointer to the read data.
 *
 * Return: 0 on success, -1 on failure.
 */
static int rsi_sdio_read_register_multiple(struct rsi_hw *adapter,
					   u32 addr,
					   u32 count,
					   u8 *data)
{
	struct rsi_91x_sdiodev *dev =
		(struct rsi_91x_sdiodev *)adapter->rsi_dev;
	u32 status;

	sdio_claim_host(dev->pfunction);

	status =  sdio_readsb(dev->pfunction, data, addr, count);

	sdio_release_host(dev->pfunction);

	if (status != 0)
		rsi_dbg(ERR_ZONE, "%s: Synch Cmd53 read failed\n", __func__);
	return status;
}

/**
 * rsi_sdio_write_register_multiple() - This function writes multiple bytes of
 *					information to the SD card.
 * @adapter: Pointer to the adapter structure.
 * @addr: Address of the register.
 * @data: Pointer to the data that has to be written.
 * @count: Number of multiple bytes to be written.
 *
 * Return: 0 on success, -1 on failure.
 */
int rsi_sdio_write_register_multiple(struct rsi_hw *adapter,
				     u32 addr,
				     u8 *data,
				     u32 count)
{
	struct rsi_91x_sdiodev *dev =
		(struct rsi_91x_sdiodev *)adapter->rsi_dev;
	int status;

	if (dev->write_fail > 1) {
		rsi_dbg(ERR_ZONE, "%s: Stopping card writes\n", __func__);
		return 0;
	} else if (dev->write_fail == 1) {
		/**
		 * Assuming it is a CRC failure, we want to allow another
		 *  card write
		 */
		rsi_dbg(ERR_ZONE, "%s: Continue card writes\n", __func__);
		dev->write_fail++;
	}

	sdio_claim_host(dev->pfunction);

	status = sdio_writesb(dev->pfunction, addr, data, count);

	sdio_release_host(dev->pfunction);

	if (status) {
		rsi_dbg(ERR_ZONE, "%s: Synch Cmd53 write failed %d\n",
			__func__, status);
		dev->write_fail = 2;
	} else {
		memcpy(dev->prev_desc, data, FRAME_DESC_SZ);
	}
	return status;
}

/**
 * rsi_sdio_host_intf_write_pkt() - This function writes the packet to device.
 * @adapter: Pointer to the adapter structure.
 * @pkt: Pointer to the data to be written on to the device.
 * @len: length of the data to be written on to the device.
 *
 * Return: 0 on success, -1 on failure.
 */
static int rsi_sdio_host_intf_write_pkt(struct rsi_hw *adapter,
					u8 *pkt,
					u32 len)
{
	struct rsi_91x_sdiodev *dev =
		(struct rsi_91x_sdiodev *)adapter->rsi_dev;
	u32 block_size = dev->tx_blk_size;
	u32 num_blocks, address, length;
	u32 queueno;
	int status;

	queueno = ((pkt[1] >> 4) & 0xf);

	num_blocks = len / block_size;

	if (len % block_size)
		num_blocks++;

	address = (num_blocks * block_size | (queueno << 12));
	length  = num_blocks * block_size;

	status = rsi_sdio_write_register_multiple(adapter,
						  address,
						  (u8 *)pkt,
						  length);
	if (status)
		rsi_dbg(ERR_ZONE, "%s: Unable to write onto the card: %d\n",
			__func__, status);
	rsi_dbg(DATA_TX_ZONE, "%s: Successfully written onto card\n", __func__);
	return status;
}

/**
 * rsi_sdio_host_intf_read_pkt() - This function reads the packet
				   from the device.
 * @adapter: Pointer to the adapter data structure.
 * @pkt: Pointer to the packet data to be read from the the device.
 * @length: Length of the data to be read from the device.
 *
 * Return: 0 on success, -1 on failure.
 */
int rsi_sdio_host_intf_read_pkt(struct rsi_hw *adapter,
				u8 *pkt,
				u32 length)
{
	int status = -EINVAL;

	if (!length) {
		rsi_dbg(ERR_ZONE, "%s: Pkt size is zero\n", __func__);
		return status;
	}

	status = rsi_sdio_read_register_multiple(adapter,
						 length,
						 length, /*num of bytes*/
						 (u8 *)pkt);

	if (status)
		rsi_dbg(ERR_ZONE, "%s: Failed to read frame: %d\n", __func__,
			status);
	return status;
}

/**
 * rsi_init_sdio_interface() - This function does init specific to SDIO.
 *
 * @adapter: Pointer to the adapter data structure.
 * @pkt: Pointer to the packet data to be read from the the device.
 *
 * Return: 0 on success, -1 on failure.
 */

static int rsi_init_sdio_interface(struct rsi_hw *adapter,
				   struct sdio_func *pfunction)
{
	struct rsi_91x_sdiodev *rsi_91x_dev;
	int status = -ENOMEM;

	rsi_91x_dev = kzalloc(sizeof(*rsi_91x_dev), GFP_KERNEL);
	if (!rsi_91x_dev)
		return status;

	adapter->rsi_dev = rsi_91x_dev;

	sdio_claim_host(pfunction);

	pfunction->enable_timeout = 100;
	status = sdio_enable_func(pfunction);
	if (status) {
		rsi_dbg(ERR_ZONE, "%s: Failed to enable interface\n", __func__);
		sdio_release_host(pfunction);
		return status;
	}

	rsi_dbg(INIT_ZONE, "%s: Enabled the interface\n", __func__);

	rsi_91x_dev->pfunction = pfunction;
	adapter->device = &pfunction->dev;

	sdio_set_drvdata(pfunction, adapter);

	status = rsi_setupcard(adapter);
	if (status) {
		rsi_dbg(ERR_ZONE, "%s: Failed to setup card\n", __func__);
		goto fail;
	}

	rsi_dbg(INIT_ZONE, "%s: Setup card succesfully\n", __func__);

	status = rsi_init_sdio_slave_regs(adapter);
	if (status) {
		rsi_dbg(ERR_ZONE, "%s: Failed to init slave regs\n", __func__);
		goto fail;
	}
	sdio_release_host(pfunction);

	adapter->host_intf_write_pkt = rsi_sdio_host_intf_write_pkt;
	adapter->host_intf_read_pkt = rsi_sdio_host_intf_read_pkt;
	adapter->determine_event_timeout = rsi_sdio_determine_event_timeout;
	adapter->check_hw_queue_status = rsi_sdio_read_buffer_status_register;

#ifdef CONFIG_RSI_DEBUGFS
	adapter->num_debugfs_entries = MAX_DEBUGFS_ENTRIES;
#endif
	return status;
fail:
	sdio_disable_func(pfunction);
	sdio_release_host(pfunction);
	return status;
}

/**
 * rsi_probe() - This function is called by kernel when the driver provided
 *		 Vendor and device IDs are matched. All the initialization
 *		 work is done here.
 * @pfunction: Pointer to the sdio_func structure.
 * @id: Pointer to sdio_device_id structure.
 *
 * Return: 0 on success, 1 on failure.
 */
static int rsi_probe(struct sdio_func *pfunction,
		     const struct sdio_device_id *id)
{
	struct rsi_hw *adapter;

	rsi_dbg(INIT_ZONE, "%s: Init function called\n", __func__);

	adapter = rsi_91x_init();
	if (!adapter) {
		rsi_dbg(ERR_ZONE, "%s: Failed to init os intf ops\n",
			__func__);
		return 1;
	}

	if (rsi_init_sdio_interface(adapter, pfunction)) {
		rsi_dbg(ERR_ZONE, "%s: Failed to init sdio interface\n",
			__func__);
		goto fail;
	}

	if (rsi_sdio_device_init(adapter->priv)) {
		rsi_dbg(ERR_ZONE, "%s: Failed in device init\n", __func__);
		sdio_claim_host(pfunction);
		sdio_disable_func(pfunction);
		sdio_release_host(pfunction);
		goto fail;
	}

	sdio_claim_host(pfunction);
	if (sdio_claim_irq(pfunction, rsi_handle_interrupt)) {
		rsi_dbg(ERR_ZONE, "%s: Failed to request IRQ\n", __func__);
		sdio_release_host(pfunction);
		goto fail;
	}

	sdio_release_host(pfunction);
	rsi_dbg(INIT_ZONE, "%s: Registered Interrupt handler\n", __func__);

	return 0;
fail:
	rsi_91x_deinit(adapter);
	rsi_dbg(ERR_ZONE, "%s: Failed in probe...Exiting\n", __func__);
	return 1;
}

/**
 * rsi_disconnect() - This function performs the reverse of the probe function.
 * @pfunction: Pointer to the sdio_func structure.
 *
 * Return: void.
 */
static void rsi_disconnect(struct sdio_func *pfunction)
{
	struct rsi_hw *adapter = sdio_get_drvdata(pfunction);
	struct rsi_91x_sdiodev *dev;

	if (!adapter)
		return;

	dev = (struct rsi_91x_sdiodev *)adapter->rsi_dev;

	dev->write_fail = 2;
	rsi_mac80211_detach(adapter);

	sdio_claim_host(pfunction);
	sdio_release_irq(pfunction);
	sdio_disable_func(pfunction);
	rsi_91x_deinit(adapter);
	/* Resetting to take care of the case, where-in driver is re-loaded */
	rsi_reset_card(pfunction);
	sdio_release_host(pfunction);
}

#ifdef CONFIG_PM
static int rsi_suspend(struct device *dev)
{
	/* Not yet implemented */
	return -ENOSYS;
}

static int rsi_resume(struct device *dev)
{
	/* Not yet implemented */
	return -ENOSYS;
}

static const struct dev_pm_ops rsi_pm_ops = {
	.suspend = rsi_suspend,
	.resume = rsi_resume,
};
#endif

static const struct sdio_device_id rsi_dev_table[] =  {
	{ SDIO_DEVICE(0x303, 0x100) },
	{ SDIO_DEVICE(0x041B, 0x0301) },
	{ SDIO_DEVICE(0x041B, 0x0201) },
	{ SDIO_DEVICE(0x041B, 0x9330) },
	{ /* Blank */},
};

static struct sdio_driver rsi_driver = {
	.name       = "RSI-SDIO WLAN",
	.probe      = rsi_probe,
	.remove     = rsi_disconnect,
	.id_table   = rsi_dev_table,
#ifdef CONFIG_PM
	.drv = {
		.pm = &rsi_pm_ops,
	}
#endif
};

/**
 * rsi_module_init() - This function registers the sdio module.
 * @void: Void.
 *
 * Return: 0 on success.
 */
static int rsi_module_init(void)
{
	int ret;

	ret = sdio_register_driver(&rsi_driver);
	rsi_dbg(INIT_ZONE, "%s: Registering driver\n", __func__);
	return ret;
}

/**
 * rsi_module_exit() - This function unregisters the sdio module.
 * @void: Void.
 *
 * Return: None.
 */
static void rsi_module_exit(void)
{
	sdio_unregister_driver(&rsi_driver);
	rsi_dbg(INFO_ZONE, "%s: Unregistering driver\n", __func__);
}

module_init(rsi_module_init);
module_exit(rsi_module_exit);

MODULE_AUTHOR("Redpine Signals Inc");
MODULE_DESCRIPTION("Common SDIO layer for RSI drivers");
MODULE_SUPPORTED_DEVICE("RSI-91x");
MODULE_DEVICE_TABLE(sdio, rsi_dev_table);
MODULE_FIRMWARE(FIRMWARE_RSI9113);
MODULE_VERSION("0.1");
MODULE_LICENSE("Dual BSD/GPL");