text: /*
   *  Shared Transport Line discipline driver Core
   *	Init Manager module responsible for GPIO control
   *	and firmware download
   *  Copyright (C) 2009-2010 Texas Instruments
   *  Author: Pavan Savoy <pavan_savoy@ti.com>
   *
   *  This program is free software; you can redistribute it and/or modify
   *  it under the terms of the GNU General Public License version 2 as
   *  published by the Free Software Foundation.
   *
   *  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
   *
   */
  
  #define pr_fmt(fmt) "(stk) :" fmt
  #include <linux/platform_device.h>
  #include <linux/jiffies.h>
  #include <linux/firmware.h>
  #include <linux/delay.h>
  #include <linux/wait.h>
  #include <linux/gpio.h>
  #include <linux/debugfs.h>
  #include <linux/seq_file.h>
  #include <linux/sched.h>
  #include <linux/sysfs.h>
  #include <linux/tty.h>
  
  #include <linux/skbuff.h>
  #include <linux/ti_wilink_st.h>
  #include <linux/module.h>
  
  #define MAX_ST_DEVICES	3	/* Imagine 1 on each UART for now */
  static struct platform_device *st_kim_devices[MAX_ST_DEVICES];
  
  /**********************************************************************/
  /* internal functions */
  
  /**
   * st_get_plat_device -
   *	function which returns the reference to the platform device
   *	requested by id. As of now only 1 such device exists (id=0)
   *	the context requesting for reference can get the id to be
   *	requested by a. The protocol driver which is registering or
   *	b. the tty device which is opened.
   */
  static struct platform_device *st_get_plat_device(int id)
  {
  	return st_kim_devices[id];
  }
  
  /**
   * validate_firmware_response -
   *	function to return whether the firmware response was proper
   *	in case of error don't complete so that waiting for proper
   *	response times out
   */
  static void validate_firmware_response(struct kim_data_s *kim_gdata)
  {
  	struct sk_buff *skb = kim_gdata->rx_skb;
  	if (!skb)
  		return;
  
  	/* these magic numbers are the position in the response buffer which
  	 * allows us to distinguish whether the response is for the read
  	 * version info. command
  	 */
  	if (skb->data[2] == 0x01 && skb->data[3] == 0x01 &&
  			skb->data[4] == 0x10 && skb->data[5] == 0x00) {
  		/* fw version response */
  		memcpy(kim_gdata->resp_buffer,
  				kim_gdata->rx_skb->data,
  				kim_gdata->rx_skb->len);
  		kim_gdata->rx_state = ST_W4_PACKET_TYPE;
  		kim_gdata->rx_skb = NULL;
  		kim_gdata->rx_count = 0;
  	} else if (unlikely(skb->data[5] != 0)) {
  		pr_err("no proper response during fw download");
  		pr_err("data6 %x", skb->data[5]);
  		kfree_skb(skb);
  		return;		/* keep waiting for the proper response */
  	}
  	/* becos of all the script being downloaded */
  	complete_all(&kim_gdata->kim_rcvd);
  	kfree_skb(skb);
  }
  
  /* check for data len received inside kim_int_recv
   * most often hit the last case to update state to waiting for data
   */
  static inline int kim_check_data_len(struct kim_data_s *kim_gdata, int len)
  {
  	register int room = skb_tailroom(kim_gdata->rx_skb);
  
  	pr_debug("len %d room %d", len, room);
  
  	if (!len) {
  		validate_firmware_response(kim_gdata);
  	} else if (len > room) {
  		/* Received packet's payload length is larger.
  		 * We can't accommodate it in created skb.
  		 */
  		pr_err("Data length is too large len %d room %d", len,
  			   room);
  		kfree_skb(kim_gdata->rx_skb);
  	} else {
  		/* Packet header has non-zero payload length and
  		 * we have enough space in created skb. Lets read
  		 * payload data */
  		kim_gdata->rx_state = ST_W4_DATA;
  		kim_gdata->rx_count = len;
  		return len;
  	}
  
  	/* Change ST LL state to continue to process next
  	 * packet */
  	kim_gdata->rx_state = ST_W4_PACKET_TYPE;
  	kim_gdata->rx_skb = NULL;
  	kim_gdata->rx_count = 0;
  
  	return 0;
  }
  
  /**
   * kim_int_recv - receive function called during firmware download
   *	firmware download responses on different UART drivers
   *	have been observed to come in bursts of different
   *	tty_receive and hence the logic
   */
  static void kim_int_recv(struct kim_data_s *kim_gdata,
  	const unsigned char *data, long count)
  {
  	const unsigned char *ptr;
  	int len = 0, type = 0;
  	unsigned char *plen;
  
  	pr_debug("%s", __func__);
  	/* Decode received bytes here */
  	ptr = data;
  	if (unlikely(ptr == NULL)) {
  		pr_err(" received null from TTY ");
  		return;
  	}
  
  	while (count) {
  		if (kim_gdata->rx_count) {
  			len = min_t(unsigned int, kim_gdata->rx_count, count);
  			skb_put_data(kim_gdata->rx_skb, ptr, len);
  			kim_gdata->rx_count -= len;
  			count -= len;
  			ptr += len;
  
  			if (kim_gdata->rx_count)
  				continue;
  
  			/* Check ST RX state machine , where are we? */
  			switch (kim_gdata->rx_state) {
  				/* Waiting for complete packet ? */
  			case ST_W4_DATA:
  				pr_debug("Complete pkt received");
  				validate_firmware_response(kim_gdata);
  				kim_gdata->rx_state = ST_W4_PACKET_TYPE;
  				kim_gdata->rx_skb = NULL;
  				continue;
  				/* Waiting for Bluetooth event header ? */
  			case ST_W4_HEADER:
  				plen =
  				(unsigned char *)&kim_gdata->rx_skb->data[1];
  				pr_debug("event hdr: plen 0x%02x\n", *plen);
  				kim_check_data_len(kim_gdata, *plen);
  				continue;
  			}	/* end of switch */
  		}		/* end of if rx_state */
  		switch (*ptr) {
  			/* Bluetooth event packet? */
  		case 0x04:
  			kim_gdata->rx_state = ST_W4_HEADER;
  			kim_gdata->rx_count = 2;
  			type = *ptr;
  			break;
  		default:
  			pr_info("unknown packet");
  			ptr++;
  			count--;
  			continue;
  		}
  		ptr++;
  		count--;
  		kim_gdata->rx_skb =
  			alloc_skb(1024+8, GFP_ATOMIC);
  		if (!kim_gdata->rx_skb) {
  			pr_err("can't allocate mem for new packet");
  			kim_gdata->rx_state = ST_W4_PACKET_TYPE;
  			kim_gdata->rx_count = 0;
  			return;
  		}
  		skb_reserve(kim_gdata->rx_skb, 8);
  		kim_gdata->rx_skb->cb[0] = 4;
  		kim_gdata->rx_skb->cb[1] = 0;
  
  	}
  	return;
  }
  
  static long read_local_version(struct kim_data_s *kim_gdata, char *bts_scr_name)
  {
  	unsigned short version = 0, chip = 0, min_ver = 0, maj_ver = 0;
  	const char read_ver_cmd[] = { 0x01, 0x01, 0x10, 0x00 };
  	long timeout;
  
  	pr_debug("%s", __func__);
  
  	reinit_completion(&kim_gdata->kim_rcvd);
  	if (4 != st_int_write(kim_gdata->core_data, read_ver_cmd, 4)) {
  		pr_err("kim: couldn't write 4 bytes");
  		return -EIO;
  	}
  
  	timeout = wait_for_completion_interruptible_timeout(
  		&kim_gdata->kim_rcvd, msecs_to_jiffies(CMD_RESP_TIME));
  	if (timeout <= 0) {
  		pr_err(" waiting for ver info- timed out or received signal");
  		return timeout ? -ERESTARTSYS : -ETIMEDOUT;
  	}
  	reinit_completion(&kim_gdata->kim_rcvd);
  	/* the positions 12 & 13 in the response buffer provide with the
  	 * chip, major & minor numbers
  	 */
  
  	version =
  		MAKEWORD(kim_gdata->resp_buffer[12],
  				kim_gdata->resp_buffer[13]);
  	chip = (version & 0x7C00) >> 10;
  	min_ver = (version & 0x007F);
  	maj_ver = (version & 0x0380) >> 7;
  
  	if (version & 0x8000)
  		maj_ver |= 0x0008;
  
  	sprintf(bts_scr_name, "ti-connectivity/TIInit_%d.%d.%d.bts",
  		chip, maj_ver, min_ver);
  
  	/* to be accessed later via sysfs entry */
  	kim_gdata->version.full = version;
  	kim_gdata->version.chip = chip;
  	kim_gdata->version.maj_ver = maj_ver;
  	kim_gdata->version.min_ver = min_ver;
  
  	pr_info("%s", bts_scr_name);
  	return 0;
  }
  
  static void skip_change_remote_baud(unsigned char **ptr, long *len)
  {
  	unsigned char *nxt_action, *cur_action;
  	cur_action = *ptr;
  
  	nxt_action = cur_action + sizeof(struct bts_action) +
  		((struct bts_action *) cur_action)->size;
  
  	if (((struct bts_action *) nxt_action)->type != ACTION_WAIT_EVENT) {
  		pr_err("invalid action after change remote baud command");
  	} else {
  		*ptr = *ptr + sizeof(struct bts_action) +
  			((struct bts_action *)cur_action)->size;
  		*len = *len - (sizeof(struct bts_action) +
  				((struct bts_action *)cur_action)->size);
  		/* warn user on not commenting these in firmware */
  		pr_warn("skipping the wait event of change remote baud");
  	}
  }
  
  /**
   * download_firmware -
   *	internal function which parses through the .bts firmware
   *	script file intreprets SEND, DELAY actions only as of now
   */
  static long download_firmware(struct kim_data_s *kim_gdata)
  {
  	long err = 0;
  	long len = 0;
  	unsigned char *ptr = NULL;
  	unsigned char *action_ptr = NULL;
  	unsigned char bts_scr_name[40] = { 0 };	/* 40 char long bts scr name? */
  	int wr_room_space;
  	int cmd_size;
  	unsigned long timeout;
  
  	err = read_local_version(kim_gdata, bts_scr_name);
  	if (err != 0) {
  		pr_err("kim: failed to read local ver");
  		return err;
  	}
  	err =
  	    request_firmware(&kim_gdata->fw_entry, bts_scr_name,
  			     &kim_gdata->kim_pdev->dev);
  	if (unlikely((err != 0) || (kim_gdata->fw_entry->data == NULL) ||
  		     (kim_gdata->fw_entry->size == 0))) {
  		pr_err(" request_firmware failed(errno %ld) for %s", err,
  			   bts_scr_name);
  		return -EINVAL;
  	}
  	ptr = (void *)kim_gdata->fw_entry->data;
  	len = kim_gdata->fw_entry->size;
  	/* bts_header to remove out magic number and
  	 * version
  	 */
  	ptr += sizeof(struct bts_header);
  	len -= sizeof(struct bts_header);
  
  	while (len > 0 && ptr) {
  		pr_debug(" action size %d, type %d ",
  			   ((struct bts_action *)ptr)->size,
  			   ((struct bts_action *)ptr)->type);
  
  		switch (((struct bts_action *)ptr)->type) {
  		case ACTION_SEND_COMMAND:	/* action send */
  			pr_debug("S");
  			action_ptr = &(((struct bts_action *)ptr)->data[0]);
  			if (unlikely
  			    (((struct hci_command *)action_ptr)->opcode ==
  			     0xFF36)) {
  				/* ignore remote change
  				 * baud rate HCI VS command */
  				pr_warn("change remote baud"
  				    " rate command in firmware");
  				skip_change_remote_baud(&ptr, &len);
  				break;
  			}
  			/*
  			 * Make sure we have enough free space in uart
  			 * tx buffer to write current firmware command
  			 */
  			cmd_size = ((struct bts_action *)ptr)->size;
  			timeout = jiffies + msecs_to_jiffies(CMD_WR_TIME);
  			do {
  				wr_room_space =
  					st_get_uart_wr_room(kim_gdata->core_data);
  				if (wr_room_space < 0) {
  					pr_err("Unable to get free "
  							"space info from uart tx buffer");
  					release_firmware(kim_gdata->fw_entry);
  					return wr_room_space;
  				}
  				mdelay(1); /* wait 1ms before checking room */
  			} while ((wr_room_space < cmd_size) &&
  					time_before(jiffies, timeout));
  
  			/* Timeout happened ? */
  			if (time_after_eq(jiffies, timeout)) {
  				pr_err("Timeout while waiting for free "
  						"free space in uart tx buffer");
  				release_firmware(kim_gdata->fw_entry);
  				return -ETIMEDOUT;
  			}
  			/* reinit completion before sending for the
  			 * relevant wait
  			 */
  			reinit_completion(&kim_gdata->kim_rcvd);
  
  			/*
  			 * Free space found in uart buffer, call st_int_write
  			 * to send current firmware command to the uart tx
  			 * buffer.
  			 */
  			err = st_int_write(kim_gdata->core_data,
  			((struct bts_action_send *)action_ptr)->data,
  					   ((struct bts_action *)ptr)->size);
  			if (unlikely(err < 0)) {
  				release_firmware(kim_gdata->fw_entry);
  				return err;
  			}
  			/*
  			 * Check number of bytes written to the uart tx buffer
  			 * and requested command write size
  			 */
  			if (err != cmd_size) {
  				pr_err("Number of bytes written to uart "
  						"tx buffer are not matching with "
  						"requested cmd write size");
  				release_firmware(kim_gdata->fw_entry);
  				return -EIO;
  			}
  			break;
  		case ACTION_WAIT_EVENT:  /* wait */
  			pr_debug("W");
  			err = wait_for_completion_interruptible_timeout(
  					&kim_gdata->kim_rcvd,
  					msecs_to_jiffies(CMD_RESP_TIME));
  			if (err <= 0) {
  				pr_err("response timeout/signaled during fw download ");
  				/* timed out */
  				release_firmware(kim_gdata->fw_entry);
  				return err ? -ERESTARTSYS : -ETIMEDOUT;
  			}
  			reinit_completion(&kim_gdata->kim_rcvd);
  			break;
  		case ACTION_DELAY:	/* sleep */
  			pr_info("sleep command in scr");
  			action_ptr = &(((struct bts_action *)ptr)->data[0]);
  			mdelay(((struct bts_action_delay *)action_ptr)->msec);
  			break;
  		}
  		len =
  		    len - (sizeof(struct bts_action) +
  			   ((struct bts_action *)ptr)->size);
  		ptr =
  		    ptr + sizeof(struct bts_action) +
  		    ((struct bts_action *)ptr)->size;
  	}
  	/* fw download complete */
  	release_firmware(kim_gdata->fw_entry);
  	return 0;
  }
  
  /**********************************************************************/
  /* functions called from ST core */
  /* called from ST Core, when REG_IN_PROGRESS (registration in progress)
   * can be because of
   * 1. response to read local version
   * 2. during send/recv's of firmware download
   */
  void st_kim_recv(void *disc_data, const unsigned char *data, long count)
  {
  	struct st_data_s	*st_gdata = (struct st_data_s *)disc_data;
  	struct kim_data_s	*kim_gdata = st_gdata->kim_data;
  
  	/* proceed to gather all data and distinguish read fw version response
  	 * from other fw responses when data gathering is complete
  	 */
  	kim_int_recv(kim_gdata, data, count);
  	return;
  }
  
  /* to signal completion of line discipline installation
   * called from ST Core, upon tty_open
   */
  void st_kim_complete(void *kim_data)
  {
  	struct kim_data_s	*kim_gdata = (struct kim_data_s *)kim_data;
  	complete(&kim_gdata->ldisc_installed);
  }
  
  /**
   * st_kim_start - called from ST Core upon 1st registration
   *	This involves toggling the chip enable gpio, reading
   *	the firmware version from chip, forming the fw file name
   *	based on the chip version, requesting the fw, parsing it
   *	and perform download(send/recv).
   */
  long st_kim_start(void *kim_data)
  {
  	long err = 0;
  	long retry = POR_RETRY_COUNT;
  	struct ti_st_plat_data	*pdata;
  	struct kim_data_s	*kim_gdata = (struct kim_data_s *)kim_data;
  
  	pr_info(" %s", __func__);
  	pdata = kim_gdata->kim_pdev->dev.platform_data;
  
  	do {
  		/* platform specific enabling code here */
  		if (pdata->chip_enable)
  			pdata->chip_enable(kim_gdata);
  
  		/* Configure BT nShutdown to HIGH state */
  		gpio_set_value_cansleep(kim_gdata->nshutdown, GPIO_LOW);
  		mdelay(5);	/* FIXME: a proper toggle */
  		gpio_set_value_cansleep(kim_gdata->nshutdown, GPIO_HIGH);
  		mdelay(100);
  		/* re-initialize the completion */
  		reinit_completion(&kim_gdata->ldisc_installed);
  		/* send notification to UIM */
  		kim_gdata->ldisc_install = 1;
  		pr_info("ldisc_install = 1");
  		sysfs_notify(&kim_gdata->kim_pdev->dev.kobj,
  				NULL, "install");
  		/* wait for ldisc to be installed */
  		err = wait_for_completion_interruptible_timeout(
  			&kim_gdata->ldisc_installed, msecs_to_jiffies(LDISC_TIME));
  		if (!err) {
  			/* ldisc installation timeout,
  			 * flush uart, power cycle BT_EN */
  			pr_err("ldisc installation timeout");
  			err = st_kim_stop(kim_gdata);
  			continue;
  		} else {
  			/* ldisc installed now */
  			pr_info("line discipline installed");
  			err = download_firmware(kim_gdata);
  			if (err != 0) {
  				/* ldisc installed but fw download failed,
  				 * flush uart & power cycle BT_EN */
  				pr_err("download firmware failed");
  				err = st_kim_stop(kim_gdata);
  				continue;
  			} else {	/* on success don't retry */
  				break;
  			}
  		}
  	} while (retry--);
  	return err;
  }
  
  /**
   * st_kim_stop - stop communication with chip.
   *	This can be called from ST Core/KIM, on the-
   *	(a) last un-register when chip need not be powered there-after,
   *	(b) upon failure to either install ldisc or download firmware.
   *	The function is responsible to (a) notify UIM about un-installation,
   *	(b) flush UART if the ldisc was installed.
   *	(c) reset BT_EN - pull down nshutdown at the end.
   *	(d) invoke platform's chip disabling routine.
   */
  long st_kim_stop(void *kim_data)
  {
  	long err = 0;
  	struct kim_data_s	*kim_gdata = (struct kim_data_s *)kim_data;
  	struct ti_st_plat_data	*pdata =
  		kim_gdata->kim_pdev->dev.platform_data;
  	struct tty_struct	*tty = kim_gdata->core_data->tty;
  
  	reinit_completion(&kim_gdata->ldisc_installed);
  
  	if (tty) {	/* can be called before ldisc is installed */
  		/* Flush any pending characters in the driver and discipline. */
  		tty_ldisc_flush(tty);
  		tty_driver_flush_buffer(tty);
  	}
  
  	/* send uninstall notification to UIM */
  	pr_info("ldisc_install = 0");
  	kim_gdata->ldisc_install = 0;
  	sysfs_notify(&kim_gdata->kim_pdev->dev.kobj, NULL, "install");
  
  	/* wait for ldisc to be un-installed */
  	err = wait_for_completion_interruptible_timeout(
  		&kim_gdata->ldisc_installed, msecs_to_jiffies(LDISC_TIME));
  	if (!err) {		/* timeout */
  		pr_err(" timed out waiting for ldisc to be un-installed");
  		err = -ETIMEDOUT;
  	}
  
  	/* By default configure BT nShutdown to LOW state */
  	gpio_set_value_cansleep(kim_gdata->nshutdown, GPIO_LOW);
  	mdelay(1);
  	gpio_set_value_cansleep(kim_gdata->nshutdown, GPIO_HIGH);
  	mdelay(1);
  	gpio_set_value_cansleep(kim_gdata->nshutdown, GPIO_LOW);
  
  	/* platform specific disable */
  	if (pdata->chip_disable)
  		pdata->chip_disable(kim_gdata);
  	return err;
  }
  
  /**********************************************************************/
  /* functions called from subsystems */
  /* called when debugfs entry is read from */
  
  static int show_version(struct seq_file *s, void *unused)
  {
  	struct kim_data_s *kim_gdata = (struct kim_data_s *)s->private;
  	seq_printf(s, "%04X %d.%d.%d\n", kim_gdata->version.full,
  			kim_gdata->version.chip, kim_gdata->version.maj_ver,
  			kim_gdata->version.min_ver);
  	return 0;
  }
  
  static int show_list(struct seq_file *s, void *unused)
  {
  	struct kim_data_s *kim_gdata = (struct kim_data_s *)s->private;
  	kim_st_list_protocols(kim_gdata->core_data, s);
  	return 0;
  }
  
  static ssize_t show_install(struct device *dev,
  		struct device_attribute *attr, char *buf)
  {
  	struct kim_data_s *kim_data = dev_get_drvdata(dev);
  	return sprintf(buf, "%d\n", kim_data->ldisc_install);
  }
  
  #ifdef DEBUG
  static ssize_t store_dev_name(struct device *dev,
  		struct device_attribute *attr, const char *buf, size_t count)
  {
  	struct kim_data_s *kim_data = dev_get_drvdata(dev);
  	pr_debug("storing dev name >%s<", buf);
  	strncpy(kim_data->dev_name, buf, count);
  	pr_debug("stored dev name >%s<", kim_data->dev_name);
  	return count;
  }
  
  static ssize_t store_baud_rate(struct device *dev,
  		struct device_attribute *attr, const char *buf, size_t count)
  {
  	struct kim_data_s *kim_data = dev_get_drvdata(dev);
  	pr_debug("storing baud rate >%s<", buf);
  	sscanf(buf, "%ld", &kim_data->baud_rate);
  	pr_debug("stored baud rate >%ld<", kim_data->baud_rate);
  	return count;
  }
  #endif	/* if DEBUG */
  
  static ssize_t show_dev_name(struct device *dev,
  		struct device_attribute *attr, char *buf)
  {
  	struct kim_data_s *kim_data = dev_get_drvdata(dev);
  	return sprintf(buf, "%s\n", kim_data->dev_name);
  }
  
  static ssize_t show_baud_rate(struct device *dev,
  		struct device_attribute *attr, char *buf)
  {
  	struct kim_data_s *kim_data = dev_get_drvdata(dev);
  	return sprintf(buf, "%d\n", kim_data->baud_rate);
  }
  
  static ssize_t show_flow_cntrl(struct device *dev,
  		struct device_attribute *attr, char *buf)
  {
  	struct kim_data_s *kim_data = dev_get_drvdata(dev);
  	return sprintf(buf, "%d\n", kim_data->flow_cntrl);
  }
  
  /* structures specific for sysfs entries */
  static struct kobj_attribute ldisc_install =
  __ATTR(install, 0444, (void *)show_install, NULL);
  
  static struct kobj_attribute uart_dev_name =
  #ifdef DEBUG	/* TODO: move this to debug-fs if possible */
  __ATTR(dev_name, 0644, (void *)show_dev_name, (void *)store_dev_name);
  #else
  __ATTR(dev_name, 0444, (void *)show_dev_name, NULL);
  #endif
  
  static struct kobj_attribute uart_baud_rate =
  #ifdef DEBUG	/* TODO: move to debugfs */
  __ATTR(baud_rate, 0644, (void *)show_baud_rate, (void *)store_baud_rate);
  #else
  __ATTR(baud_rate, 0444, (void *)show_baud_rate, NULL);
  #endif
  
  static struct kobj_attribute uart_flow_cntrl =
  __ATTR(flow_cntrl, 0444, (void *)show_flow_cntrl, NULL);
  
  static struct attribute *uim_attrs[] = {
  	&ldisc_install.attr,
  	&uart_dev_name.attr,
  	&uart_baud_rate.attr,
  	&uart_flow_cntrl.attr,
  	NULL,
  };
  
  static const struct attribute_group uim_attr_grp = {
  	.attrs = uim_attrs,
  };
  
  /**
   * st_kim_ref - reference the core's data
   *	This references the per-ST platform device in the arch/xx/
   *	board-xx.c file.
   *	This would enable multiple such platform devices to exist
   *	on a given platform
   */
  void st_kim_ref(struct st_data_s **core_data, int id)
  {
  	struct platform_device	*pdev;
  	struct kim_data_s	*kim_gdata;
  	/* get kim_gdata reference from platform device */
  	pdev = st_get_plat_device(id);
  	if (!pdev)
  		goto err;
  	kim_gdata = platform_get_drvdata(pdev);
  	if (!kim_gdata)
  		goto err;
  
  	*core_data = kim_gdata->core_data;
  	return;
  err:
  	*core_data = NULL;
  }
  
  static int kim_version_open(struct inode *i, struct file *f)
  {
  	return single_open(f, show_version, i->i_private);
  }
  
  static int kim_list_open(struct inode *i, struct file *f)
  {
  	return single_open(f, show_list, i->i_private);
  }
  
  static const struct file_operations version_debugfs_fops = {
  	/* version info */
  	.open = kim_version_open,
  	.read = seq_read,
  	.llseek = seq_lseek,
  	.release = single_release,
  };
  static const struct file_operations list_debugfs_fops = {
  	/* protocols info */
  	.open = kim_list_open,
  	.read = seq_read,
  	.llseek = seq_lseek,
  	.release = single_release,
  };
  
  /**********************************************************************/
  /* functions called from platform device driver subsystem
   * need to have a relevant platform device entry in the platform's
   * board-*.c file
   */
  
  static struct dentry *kim_debugfs_dir;
  static int kim_probe(struct platform_device *pdev)
  {
  	struct kim_data_s	*kim_gdata;
  	struct ti_st_plat_data	*pdata = pdev->dev.platform_data;
  	int err;
  
  	if ((pdev->id != -1) && (pdev->id < MAX_ST_DEVICES)) {
  		/* multiple devices could exist */
  		st_kim_devices[pdev->id] = pdev;
  	} else {
  		/* platform's sure about existence of 1 device */
  		st_kim_devices[0] = pdev;
  	}
  
  	kim_gdata = kzalloc(sizeof(struct kim_data_s), GFP_ATOMIC);
  	if (!kim_gdata) {
  		pr_err("no mem to allocate");
  		return -ENOMEM;
  	}
  	platform_set_drvdata(pdev, kim_gdata);
  
  	err = st_core_init(&kim_gdata->core_data);
  	if (err != 0) {
  		pr_err(" ST core init failed");
  		err = -EIO;
  		goto err_core_init;
  	}
  	/* refer to itself */
  	kim_gdata->core_data->kim_data = kim_gdata;
  
  	/* Claim the chip enable nShutdown gpio from the system */
  	kim_gdata->nshutdown = pdata->nshutdown_gpio;
  	err = gpio_request(kim_gdata->nshutdown, "kim");
  	if (unlikely(err)) {
  		pr_err(" gpio %d request failed ", kim_gdata->nshutdown);
  		return err;
  	}
  
  	/* Configure nShutdown GPIO as output=0 */
  	err = gpio_direction_output(kim_gdata->nshutdown, 0);
  	if (unlikely(err)) {
  		pr_err(" unable to configure gpio %d", kim_gdata->nshutdown);
  		return err;
  	}
  	/* get reference of pdev for request_firmware
  	 */
  	kim_gdata->kim_pdev = pdev;
  	init_completion(&kim_gdata->kim_rcvd);
  	init_completion(&kim_gdata->ldisc_installed);
  
  	err = sysfs_create_group(&pdev->dev.kobj, &uim_attr_grp);
  	if (err) {
  		pr_err("failed to create sysfs entries");
  		goto err_sysfs_group;
  	}
  
  	/* copying platform data */
  	strncpy(kim_gdata->dev_name, pdata->dev_name, UART_DEV_NAME_LEN);
  	kim_gdata->flow_cntrl = pdata->flow_cntrl;
  	kim_gdata->baud_rate = pdata->baud_rate;
  	pr_info("sysfs entries created\n");
  
  	kim_debugfs_dir = debugfs_create_dir("ti-st", NULL);
  	if (!kim_debugfs_dir) {
  		pr_err(" debugfs entries creation failed ");
  		return 0;
  	}
  
  	debugfs_create_file("version", S_IRUGO, kim_debugfs_dir,
  				kim_gdata, &version_debugfs_fops);
  	debugfs_create_file("protocols", S_IRUGO, kim_debugfs_dir,
  				kim_gdata, &list_debugfs_fops);
  	return 0;
  
  err_sysfs_group:
  	st_core_exit(kim_gdata->core_data);
  
  err_core_init:
  	kfree(kim_gdata);
  
  	return err;
  }
  
  static int kim_remove(struct platform_device *pdev)
  {
  	/* free the GPIOs requested */
  	struct ti_st_plat_data	*pdata = pdev->dev.platform_data;
  	struct kim_data_s	*kim_gdata;
  
  	kim_gdata = platform_get_drvdata(pdev);
  
  	/* Free the Bluetooth/FM/GPIO
  	 * nShutdown gpio from the system
  	 */
  	gpio_free(pdata->nshutdown_gpio);
  	pr_info("nshutdown GPIO Freed");
  
  	debugfs_remove_recursive(kim_debugfs_dir);
  	sysfs_remove_group(&pdev->dev.kobj, &uim_attr_grp);
  	pr_info("sysfs entries removed");
  
  	kim_gdata->kim_pdev = NULL;
  	st_core_exit(kim_gdata->core_data);
  
  	kfree(kim_gdata);
  	kim_gdata = NULL;
  	return 0;
  }
  
  static int kim_suspend(struct platform_device *pdev, pm_message_t state)
  {
  	struct ti_st_plat_data	*pdata = pdev->dev.platform_data;
  
  	if (pdata->suspend)
  		return pdata->suspend(pdev, state);
  
  	return 0;
  }
  
  static int kim_resume(struct platform_device *pdev)
  {
  	struct ti_st_plat_data	*pdata = pdev->dev.platform_data;
  
  	if (pdata->resume)
  		return pdata->resume(pdev);
  
  	return 0;
  }
  
  /**********************************************************************/
  /* entry point for ST KIM module, called in from ST Core */
  static struct platform_driver kim_platform_driver = {
  	.probe = kim_probe,
  	.remove = kim_remove,
  	.suspend = kim_suspend,
  	.resume = kim_resume,
  	.driver = {
  		.name = "kim",
  	},
  };
  
  module_platform_driver(kim_platform_driver);
  
  MODULE_AUTHOR("Pavan Savoy <pavan_savoy@ti.com>");
  MODULE_DESCRIPTION("Shared Transport Driver for TI BT/FM/GPS combo chips ");
  MODULE_LICENSE("GPL");
  