cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
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st_kim.c (23818B)


      1// SPDX-License-Identifier: GPL-2.0-only
      2/*
      3 *  Shared Transport Line discipline driver Core
      4 *	Init Manager module responsible for GPIO control
      5 *	and firmware download
      6 *  Copyright (C) 2009-2010 Texas Instruments
      7 *  Author: Pavan Savoy <pavan_savoy@ti.com>
      8 */
      9
     10#define pr_fmt(fmt) "(stk) :" fmt
     11#include <linux/platform_device.h>
     12#include <linux/jiffies.h>
     13#include <linux/firmware.h>
     14#include <linux/delay.h>
     15#include <linux/wait.h>
     16#include <linux/gpio.h>
     17#include <linux/debugfs.h>
     18#include <linux/seq_file.h>
     19#include <linux/sched.h>
     20#include <linux/sysfs.h>
     21#include <linux/tty.h>
     22
     23#include <linux/skbuff.h>
     24#include <linux/ti_wilink_st.h>
     25#include <linux/module.h>
     26
     27#define MAX_ST_DEVICES	3	/* Imagine 1 on each UART for now */
     28static struct platform_device *st_kim_devices[MAX_ST_DEVICES];
     29
     30/**********************************************************************/
     31/* internal functions */
     32
     33/*
     34 * st_get_plat_device -
     35 *	function which returns the reference to the platform device
     36 *	requested by id. As of now only 1 such device exists (id=0)
     37 *	the context requesting for reference can get the id to be
     38 *	requested by a. The protocol driver which is registering or
     39 *	b. the tty device which is opened.
     40 */
     41static struct platform_device *st_get_plat_device(int id)
     42{
     43	return st_kim_devices[id];
     44}
     45
     46/*
     47 * validate_firmware_response -
     48 *	function to return whether the firmware response was proper
     49 *	in case of error don't complete so that waiting for proper
     50 *	response times out
     51 */
     52static void validate_firmware_response(struct kim_data_s *kim_gdata)
     53{
     54	struct sk_buff *skb = kim_gdata->rx_skb;
     55	if (!skb)
     56		return;
     57
     58	/*
     59	 * these magic numbers are the position in the response buffer which
     60	 * allows us to distinguish whether the response is for the read
     61	 * version info. command
     62	 */
     63	if (skb->data[2] == 0x01 && skb->data[3] == 0x01 &&
     64			skb->data[4] == 0x10 && skb->data[5] == 0x00) {
     65		/* fw version response */
     66		memcpy(kim_gdata->resp_buffer,
     67				kim_gdata->rx_skb->data,
     68				kim_gdata->rx_skb->len);
     69		kim_gdata->rx_state = ST_W4_PACKET_TYPE;
     70		kim_gdata->rx_skb = NULL;
     71		kim_gdata->rx_count = 0;
     72	} else if (unlikely(skb->data[5] != 0)) {
     73		pr_err("no proper response during fw download");
     74		pr_err("data6 %x", skb->data[5]);
     75		kfree_skb(skb);
     76		return;		/* keep waiting for the proper response */
     77	}
     78	/* becos of all the script being downloaded */
     79	complete_all(&kim_gdata->kim_rcvd);
     80	kfree_skb(skb);
     81}
     82
     83/*
     84 * check for data len received inside kim_int_recv
     85 * most often hit the last case to update state to waiting for data
     86 */
     87static inline int kim_check_data_len(struct kim_data_s *kim_gdata, int len)
     88{
     89	register int room = skb_tailroom(kim_gdata->rx_skb);
     90
     91	pr_debug("len %d room %d", len, room);
     92
     93	if (!len) {
     94		validate_firmware_response(kim_gdata);
     95	} else if (len > room) {
     96		/*
     97		 * Received packet's payload length is larger.
     98		 * We can't accommodate it in created skb.
     99		 */
    100		pr_err("Data length is too large len %d room %d", len,
    101			   room);
    102		kfree_skb(kim_gdata->rx_skb);
    103	} else {
    104		/*
    105		 * Packet header has non-zero payload length and
    106		 * we have enough space in created skb. Lets read
    107		 * payload data */
    108		kim_gdata->rx_state = ST_W4_DATA;
    109		kim_gdata->rx_count = len;
    110		return len;
    111	}
    112
    113	/*
    114	 * Change ST LL state to continue to process next
    115	 * packet
    116	 */
    117	kim_gdata->rx_state = ST_W4_PACKET_TYPE;
    118	kim_gdata->rx_skb = NULL;
    119	kim_gdata->rx_count = 0;
    120
    121	return 0;
    122}
    123
    124/*
    125 * kim_int_recv - receive function called during firmware download
    126 *	firmware download responses on different UART drivers
    127 *	have been observed to come in bursts of different
    128 *	tty_receive and hence the logic
    129 */
    130static void kim_int_recv(struct kim_data_s *kim_gdata,
    131	const unsigned char *data, long count)
    132{
    133	const unsigned char *ptr;
    134	int len = 0;
    135	unsigned char *plen;
    136
    137	pr_debug("%s", __func__);
    138	/* Decode received bytes here */
    139	ptr = data;
    140	if (unlikely(ptr == NULL)) {
    141		pr_err(" received null from TTY ");
    142		return;
    143	}
    144
    145	while (count) {
    146		if (kim_gdata->rx_count) {
    147			len = min_t(unsigned int, kim_gdata->rx_count, count);
    148			skb_put_data(kim_gdata->rx_skb, ptr, len);
    149			kim_gdata->rx_count -= len;
    150			count -= len;
    151			ptr += len;
    152
    153			if (kim_gdata->rx_count)
    154				continue;
    155
    156			/* Check ST RX state machine , where are we? */
    157			switch (kim_gdata->rx_state) {
    158				/* Waiting for complete packet ? */
    159			case ST_W4_DATA:
    160				pr_debug("Complete pkt received");
    161				validate_firmware_response(kim_gdata);
    162				kim_gdata->rx_state = ST_W4_PACKET_TYPE;
    163				kim_gdata->rx_skb = NULL;
    164				continue;
    165				/* Waiting for Bluetooth event header ? */
    166			case ST_W4_HEADER:
    167				plen =
    168				(unsigned char *)&kim_gdata->rx_skb->data[1];
    169				pr_debug("event hdr: plen 0x%02x\n", *plen);
    170				kim_check_data_len(kim_gdata, *plen);
    171				continue;
    172			}	/* end of switch */
    173		}		/* end of if rx_state */
    174		switch (*ptr) {
    175			/* Bluetooth event packet? */
    176		case 0x04:
    177			kim_gdata->rx_state = ST_W4_HEADER;
    178			kim_gdata->rx_count = 2;
    179			break;
    180		default:
    181			pr_info("unknown packet");
    182			ptr++;
    183			count--;
    184			continue;
    185		}
    186		ptr++;
    187		count--;
    188		kim_gdata->rx_skb =
    189			alloc_skb(1024+8, GFP_ATOMIC);
    190		if (!kim_gdata->rx_skb) {
    191			pr_err("can't allocate mem for new packet");
    192			kim_gdata->rx_state = ST_W4_PACKET_TYPE;
    193			kim_gdata->rx_count = 0;
    194			return;
    195		}
    196		skb_reserve(kim_gdata->rx_skb, 8);
    197		kim_gdata->rx_skb->cb[0] = 4;
    198		kim_gdata->rx_skb->cb[1] = 0;
    199
    200	}
    201	return;
    202}
    203
    204static long read_local_version(struct kim_data_s *kim_gdata, char *bts_scr_name)
    205{
    206	unsigned short version = 0, chip = 0, min_ver = 0, maj_ver = 0;
    207	static const char read_ver_cmd[] = { 0x01, 0x01, 0x10, 0x00 };
    208	long timeout;
    209
    210	pr_debug("%s", __func__);
    211
    212	reinit_completion(&kim_gdata->kim_rcvd);
    213	if (4 != st_int_write(kim_gdata->core_data, read_ver_cmd, 4)) {
    214		pr_err("kim: couldn't write 4 bytes");
    215		return -EIO;
    216	}
    217
    218	timeout = wait_for_completion_interruptible_timeout(
    219		&kim_gdata->kim_rcvd, msecs_to_jiffies(CMD_RESP_TIME));
    220	if (timeout <= 0) {
    221		pr_err(" waiting for ver info- timed out or received signal");
    222		return timeout ? -ERESTARTSYS : -ETIMEDOUT;
    223	}
    224	reinit_completion(&kim_gdata->kim_rcvd);
    225	/*
    226	 * the positions 12 & 13 in the response buffer provide with the
    227	 * chip, major & minor numbers
    228	 */
    229
    230	version =
    231		MAKEWORD(kim_gdata->resp_buffer[12],
    232				kim_gdata->resp_buffer[13]);
    233	chip = (version & 0x7C00) >> 10;
    234	min_ver = (version & 0x007F);
    235	maj_ver = (version & 0x0380) >> 7;
    236
    237	if (version & 0x8000)
    238		maj_ver |= 0x0008;
    239
    240	sprintf(bts_scr_name, "ti-connectivity/TIInit_%d.%d.%d.bts",
    241		chip, maj_ver, min_ver);
    242
    243	/* to be accessed later via sysfs entry */
    244	kim_gdata->version.full = version;
    245	kim_gdata->version.chip = chip;
    246	kim_gdata->version.maj_ver = maj_ver;
    247	kim_gdata->version.min_ver = min_ver;
    248
    249	pr_info("%s", bts_scr_name);
    250	return 0;
    251}
    252
    253static void skip_change_remote_baud(unsigned char **ptr, long *len)
    254{
    255	unsigned char *nxt_action, *cur_action;
    256	cur_action = *ptr;
    257
    258	nxt_action = cur_action + sizeof(struct bts_action) +
    259		((struct bts_action *) cur_action)->size;
    260
    261	if (((struct bts_action *) nxt_action)->type != ACTION_WAIT_EVENT) {
    262		pr_err("invalid action after change remote baud command");
    263	} else {
    264		*ptr = *ptr + sizeof(struct bts_action) +
    265			((struct bts_action *)cur_action)->size;
    266		*len = *len - (sizeof(struct bts_action) +
    267				((struct bts_action *)cur_action)->size);
    268		/* warn user on not commenting these in firmware */
    269		pr_warn("skipping the wait event of change remote baud");
    270	}
    271}
    272
    273/*
    274 * download_firmware -
    275 *	internal function which parses through the .bts firmware
    276 *	script file intreprets SEND, DELAY actions only as of now
    277 */
    278static long download_firmware(struct kim_data_s *kim_gdata)
    279{
    280	long err = 0;
    281	long len = 0;
    282	unsigned char *ptr = NULL;
    283	unsigned char *action_ptr = NULL;
    284	unsigned char bts_scr_name[40] = { 0 };	/* 40 char long bts scr name? */
    285	int wr_room_space;
    286	int cmd_size;
    287	unsigned long timeout;
    288
    289	err = read_local_version(kim_gdata, bts_scr_name);
    290	if (err != 0) {
    291		pr_err("kim: failed to read local ver");
    292		return err;
    293	}
    294	err =
    295	    request_firmware(&kim_gdata->fw_entry, bts_scr_name,
    296			     &kim_gdata->kim_pdev->dev);
    297	if (unlikely((err != 0) || (kim_gdata->fw_entry->data == NULL) ||
    298		     (kim_gdata->fw_entry->size == 0))) {
    299		pr_err(" request_firmware failed(errno %ld) for %s", err,
    300			   bts_scr_name);
    301		return -EINVAL;
    302	}
    303	ptr = (void *)kim_gdata->fw_entry->data;
    304	len = kim_gdata->fw_entry->size;
    305	/*
    306	 * bts_header to remove out magic number and
    307	 * version
    308	 */
    309	ptr += sizeof(struct bts_header);
    310	len -= sizeof(struct bts_header);
    311
    312	while (len > 0 && ptr) {
    313		pr_debug(" action size %d, type %d ",
    314			   ((struct bts_action *)ptr)->size,
    315			   ((struct bts_action *)ptr)->type);
    316
    317		switch (((struct bts_action *)ptr)->type) {
    318		case ACTION_SEND_COMMAND:	/* action send */
    319			pr_debug("S");
    320			action_ptr = &(((struct bts_action *)ptr)->data[0]);
    321			if (unlikely
    322			    (((struct hci_command *)action_ptr)->opcode ==
    323			     0xFF36)) {
    324				/*
    325				 * ignore remote change
    326				 * baud rate HCI VS command
    327				 */
    328				pr_warn("change remote baud"
    329				    " rate command in firmware");
    330				skip_change_remote_baud(&ptr, &len);
    331				break;
    332			}
    333			/*
    334			 * Make sure we have enough free space in uart
    335			 * tx buffer to write current firmware command
    336			 */
    337			cmd_size = ((struct bts_action *)ptr)->size;
    338			timeout = jiffies + msecs_to_jiffies(CMD_WR_TIME);
    339			do {
    340				wr_room_space =
    341					st_get_uart_wr_room(kim_gdata->core_data);
    342				if (wr_room_space < 0) {
    343					pr_err("Unable to get free "
    344							"space info from uart tx buffer");
    345					release_firmware(kim_gdata->fw_entry);
    346					return wr_room_space;
    347				}
    348				mdelay(1); /* wait 1ms before checking room */
    349			} while ((wr_room_space < cmd_size) &&
    350					time_before(jiffies, timeout));
    351
    352			/* Timeout happened ? */
    353			if (time_after_eq(jiffies, timeout)) {
    354				pr_err("Timeout while waiting for free "
    355						"free space in uart tx buffer");
    356				release_firmware(kim_gdata->fw_entry);
    357				return -ETIMEDOUT;
    358			}
    359			/*
    360			 * reinit completion before sending for the
    361			 * relevant wait
    362			 */
    363			reinit_completion(&kim_gdata->kim_rcvd);
    364
    365			/*
    366			 * Free space found in uart buffer, call st_int_write
    367			 * to send current firmware command to the uart tx
    368			 * buffer.
    369			 */
    370			err = st_int_write(kim_gdata->core_data,
    371			((struct bts_action_send *)action_ptr)->data,
    372					   ((struct bts_action *)ptr)->size);
    373			if (unlikely(err < 0)) {
    374				release_firmware(kim_gdata->fw_entry);
    375				return err;
    376			}
    377			/*
    378			 * Check number of bytes written to the uart tx buffer
    379			 * and requested command write size
    380			 */
    381			if (err != cmd_size) {
    382				pr_err("Number of bytes written to uart "
    383						"tx buffer are not matching with "
    384						"requested cmd write size");
    385				release_firmware(kim_gdata->fw_entry);
    386				return -EIO;
    387			}
    388			break;
    389		case ACTION_WAIT_EVENT:  /* wait */
    390			pr_debug("W");
    391			err = wait_for_completion_interruptible_timeout(
    392					&kim_gdata->kim_rcvd,
    393					msecs_to_jiffies(CMD_RESP_TIME));
    394			if (err <= 0) {
    395				pr_err("response timeout/signaled during fw download ");
    396				/* timed out */
    397				release_firmware(kim_gdata->fw_entry);
    398				return err ? -ERESTARTSYS : -ETIMEDOUT;
    399			}
    400			reinit_completion(&kim_gdata->kim_rcvd);
    401			break;
    402		case ACTION_DELAY:	/* sleep */
    403			pr_info("sleep command in scr");
    404			action_ptr = &(((struct bts_action *)ptr)->data[0]);
    405			mdelay(((struct bts_action_delay *)action_ptr)->msec);
    406			break;
    407		}
    408		len =
    409		    len - (sizeof(struct bts_action) +
    410			   ((struct bts_action *)ptr)->size);
    411		ptr =
    412		    ptr + sizeof(struct bts_action) +
    413		    ((struct bts_action *)ptr)->size;
    414	}
    415	/* fw download complete */
    416	release_firmware(kim_gdata->fw_entry);
    417	return 0;
    418}
    419
    420/**********************************************************************/
    421/* functions called from ST core */
    422/* called from ST Core, when REG_IN_PROGRESS (registration in progress)
    423 * can be because of
    424 * 1. response to read local version
    425 * 2. during send/recv's of firmware download
    426 */
    427void st_kim_recv(void *disc_data, const unsigned char *data, long count)
    428{
    429	struct st_data_s	*st_gdata = (struct st_data_s *)disc_data;
    430	struct kim_data_s	*kim_gdata = st_gdata->kim_data;
    431
    432	/*
    433	 * proceed to gather all data and distinguish read fw version response
    434	 * from other fw responses when data gathering is complete
    435	 */
    436	kim_int_recv(kim_gdata, data, count);
    437	return;
    438}
    439
    440/*
    441 * to signal completion of line discipline installation
    442 * called from ST Core, upon tty_open
    443 */
    444void st_kim_complete(void *kim_data)
    445{
    446	struct kim_data_s	*kim_gdata = (struct kim_data_s *)kim_data;
    447	complete(&kim_gdata->ldisc_installed);
    448}
    449
    450/*
    451 * st_kim_start - called from ST Core upon 1st registration
    452 *	This involves toggling the chip enable gpio, reading
    453 *	the firmware version from chip, forming the fw file name
    454 *	based on the chip version, requesting the fw, parsing it
    455 *	and perform download(send/recv).
    456 */
    457long st_kim_start(void *kim_data)
    458{
    459	long err = 0;
    460	long retry = POR_RETRY_COUNT;
    461	struct ti_st_plat_data	*pdata;
    462	struct kim_data_s	*kim_gdata = (struct kim_data_s *)kim_data;
    463
    464	pr_info(" %s", __func__);
    465	pdata = kim_gdata->kim_pdev->dev.platform_data;
    466
    467	do {
    468		/* platform specific enabling code here */
    469		if (pdata->chip_enable)
    470			pdata->chip_enable(kim_gdata);
    471
    472		/* Configure BT nShutdown to HIGH state */
    473		gpio_set_value_cansleep(kim_gdata->nshutdown, GPIO_LOW);
    474		mdelay(5);	/* FIXME: a proper toggle */
    475		gpio_set_value_cansleep(kim_gdata->nshutdown, GPIO_HIGH);
    476		mdelay(100);
    477		/* re-initialize the completion */
    478		reinit_completion(&kim_gdata->ldisc_installed);
    479		/* send notification to UIM */
    480		kim_gdata->ldisc_install = 1;
    481		pr_info("ldisc_install = 1");
    482		sysfs_notify(&kim_gdata->kim_pdev->dev.kobj,
    483				NULL, "install");
    484		/* wait for ldisc to be installed */
    485		err = wait_for_completion_interruptible_timeout(
    486			&kim_gdata->ldisc_installed, msecs_to_jiffies(LDISC_TIME));
    487		if (!err) {
    488			/*
    489			 * ldisc installation timeout,
    490			 * flush uart, power cycle BT_EN
    491			 */
    492			pr_err("ldisc installation timeout");
    493			err = st_kim_stop(kim_gdata);
    494			continue;
    495		} else {
    496			/* ldisc installed now */
    497			pr_info("line discipline installed");
    498			err = download_firmware(kim_gdata);
    499			if (err != 0) {
    500				/*
    501				 * ldisc installed but fw download failed,
    502				 * flush uart & power cycle BT_EN
    503				 */
    504				pr_err("download firmware failed");
    505				err = st_kim_stop(kim_gdata);
    506				continue;
    507			} else {	/* on success don't retry */
    508				break;
    509			}
    510		}
    511	} while (retry--);
    512	return err;
    513}
    514
    515/*
    516 * st_kim_stop - stop communication with chip.
    517 *	This can be called from ST Core/KIM, on the-
    518 *	(a) last un-register when chip need not be powered there-after,
    519 *	(b) upon failure to either install ldisc or download firmware.
    520 *	The function is responsible to (a) notify UIM about un-installation,
    521 *	(b) flush UART if the ldisc was installed.
    522 *	(c) reset BT_EN - pull down nshutdown at the end.
    523 *	(d) invoke platform's chip disabling routine.
    524 */
    525long st_kim_stop(void *kim_data)
    526{
    527	long err = 0;
    528	struct kim_data_s	*kim_gdata = (struct kim_data_s *)kim_data;
    529	struct ti_st_plat_data	*pdata =
    530		kim_gdata->kim_pdev->dev.platform_data;
    531	struct tty_struct	*tty = kim_gdata->core_data->tty;
    532
    533	reinit_completion(&kim_gdata->ldisc_installed);
    534
    535	if (tty) {	/* can be called before ldisc is installed */
    536		/* Flush any pending characters in the driver and discipline. */
    537		tty_ldisc_flush(tty);
    538		tty_driver_flush_buffer(tty);
    539	}
    540
    541	/* send uninstall notification to UIM */
    542	pr_info("ldisc_install = 0");
    543	kim_gdata->ldisc_install = 0;
    544	sysfs_notify(&kim_gdata->kim_pdev->dev.kobj, NULL, "install");
    545
    546	/* wait for ldisc to be un-installed */
    547	err = wait_for_completion_interruptible_timeout(
    548		&kim_gdata->ldisc_installed, msecs_to_jiffies(LDISC_TIME));
    549	if (!err) {		/* timeout */
    550		pr_err(" timed out waiting for ldisc to be un-installed");
    551		err = -ETIMEDOUT;
    552	}
    553
    554	/* By default configure BT nShutdown to LOW state */
    555	gpio_set_value_cansleep(kim_gdata->nshutdown, GPIO_LOW);
    556	mdelay(1);
    557	gpio_set_value_cansleep(kim_gdata->nshutdown, GPIO_HIGH);
    558	mdelay(1);
    559	gpio_set_value_cansleep(kim_gdata->nshutdown, GPIO_LOW);
    560
    561	/* platform specific disable */
    562	if (pdata->chip_disable)
    563		pdata->chip_disable(kim_gdata);
    564	return err;
    565}
    566
    567/**********************************************************************/
    568/* functions called from subsystems */
    569/* called when debugfs entry is read from */
    570
    571static int version_show(struct seq_file *s, void *unused)
    572{
    573	struct kim_data_s *kim_gdata = (struct kim_data_s *)s->private;
    574	seq_printf(s, "%04X %d.%d.%d\n", kim_gdata->version.full,
    575			kim_gdata->version.chip, kim_gdata->version.maj_ver,
    576			kim_gdata->version.min_ver);
    577	return 0;
    578}
    579
    580static int list_show(struct seq_file *s, void *unused)
    581{
    582	struct kim_data_s *kim_gdata = (struct kim_data_s *)s->private;
    583	kim_st_list_protocols(kim_gdata->core_data, s);
    584	return 0;
    585}
    586
    587static ssize_t show_install(struct device *dev,
    588		struct device_attribute *attr, char *buf)
    589{
    590	struct kim_data_s *kim_data = dev_get_drvdata(dev);
    591	return sprintf(buf, "%d\n", kim_data->ldisc_install);
    592}
    593
    594#ifdef DEBUG
    595static ssize_t store_dev_name(struct device *dev,
    596		struct device_attribute *attr, const char *buf, size_t count)
    597{
    598	struct kim_data_s *kim_data = dev_get_drvdata(dev);
    599	pr_debug("storing dev name >%s<", buf);
    600	strncpy(kim_data->dev_name, buf, count);
    601	pr_debug("stored dev name >%s<", kim_data->dev_name);
    602	return count;
    603}
    604
    605static ssize_t store_baud_rate(struct device *dev,
    606		struct device_attribute *attr, const char *buf, size_t count)
    607{
    608	struct kim_data_s *kim_data = dev_get_drvdata(dev);
    609	pr_debug("storing baud rate >%s<", buf);
    610	sscanf(buf, "%ld", &kim_data->baud_rate);
    611	pr_debug("stored baud rate >%ld<", kim_data->baud_rate);
    612	return count;
    613}
    614#endif	/* if DEBUG */
    615
    616static ssize_t show_dev_name(struct device *dev,
    617		struct device_attribute *attr, char *buf)
    618{
    619	struct kim_data_s *kim_data = dev_get_drvdata(dev);
    620	return sprintf(buf, "%s\n", kim_data->dev_name);
    621}
    622
    623static ssize_t show_baud_rate(struct device *dev,
    624		struct device_attribute *attr, char *buf)
    625{
    626	struct kim_data_s *kim_data = dev_get_drvdata(dev);
    627	return sprintf(buf, "%d\n", kim_data->baud_rate);
    628}
    629
    630static ssize_t show_flow_cntrl(struct device *dev,
    631		struct device_attribute *attr, char *buf)
    632{
    633	struct kim_data_s *kim_data = dev_get_drvdata(dev);
    634	return sprintf(buf, "%d\n", kim_data->flow_cntrl);
    635}
    636
    637/* structures specific for sysfs entries */
    638static struct kobj_attribute ldisc_install =
    639__ATTR(install, 0444, (void *)show_install, NULL);
    640
    641static struct kobj_attribute uart_dev_name =
    642#ifdef DEBUG	/* TODO: move this to debug-fs if possible */
    643__ATTR(dev_name, 0644, (void *)show_dev_name, (void *)store_dev_name);
    644#else
    645__ATTR(dev_name, 0444, (void *)show_dev_name, NULL);
    646#endif
    647
    648static struct kobj_attribute uart_baud_rate =
    649#ifdef DEBUG	/* TODO: move to debugfs */
    650__ATTR(baud_rate, 0644, (void *)show_baud_rate, (void *)store_baud_rate);
    651#else
    652__ATTR(baud_rate, 0444, (void *)show_baud_rate, NULL);
    653#endif
    654
    655static struct kobj_attribute uart_flow_cntrl =
    656__ATTR(flow_cntrl, 0444, (void *)show_flow_cntrl, NULL);
    657
    658static struct attribute *uim_attrs[] = {
    659	&ldisc_install.attr,
    660	&uart_dev_name.attr,
    661	&uart_baud_rate.attr,
    662	&uart_flow_cntrl.attr,
    663	NULL,
    664};
    665
    666static const struct attribute_group uim_attr_grp = {
    667	.attrs = uim_attrs,
    668};
    669
    670/*
    671 * st_kim_ref - reference the core's data
    672 *	This references the per-ST platform device in the arch/xx/
    673 *	board-xx.c file.
    674 *	This would enable multiple such platform devices to exist
    675 *	on a given platform
    676 */
    677void st_kim_ref(struct st_data_s **core_data, int id)
    678{
    679	struct platform_device	*pdev;
    680	struct kim_data_s	*kim_gdata;
    681	/* get kim_gdata reference from platform device */
    682	pdev = st_get_plat_device(id);
    683	if (!pdev)
    684		goto err;
    685	kim_gdata = platform_get_drvdata(pdev);
    686	if (!kim_gdata)
    687		goto err;
    688
    689	*core_data = kim_gdata->core_data;
    690	return;
    691err:
    692	*core_data = NULL;
    693}
    694
    695DEFINE_SHOW_ATTRIBUTE(version);
    696DEFINE_SHOW_ATTRIBUTE(list);
    697
    698/**********************************************************************/
    699/* functions called from platform device driver subsystem
    700 * need to have a relevant platform device entry in the platform's
    701 * board-*.c file
    702 */
    703
    704static struct dentry *kim_debugfs_dir;
    705static int kim_probe(struct platform_device *pdev)
    706{
    707	struct kim_data_s	*kim_gdata;
    708	struct ti_st_plat_data	*pdata = pdev->dev.platform_data;
    709	int err;
    710
    711	if ((pdev->id != -1) && (pdev->id < MAX_ST_DEVICES)) {
    712		/* multiple devices could exist */
    713		st_kim_devices[pdev->id] = pdev;
    714	} else {
    715		/* platform's sure about existence of 1 device */
    716		st_kim_devices[0] = pdev;
    717	}
    718
    719	kim_gdata = kzalloc(sizeof(struct kim_data_s), GFP_KERNEL);
    720	if (!kim_gdata) {
    721		pr_err("no mem to allocate");
    722		return -ENOMEM;
    723	}
    724	platform_set_drvdata(pdev, kim_gdata);
    725
    726	err = st_core_init(&kim_gdata->core_data);
    727	if (err != 0) {
    728		pr_err(" ST core init failed");
    729		err = -EIO;
    730		goto err_core_init;
    731	}
    732	/* refer to itself */
    733	kim_gdata->core_data->kim_data = kim_gdata;
    734
    735	/* Claim the chip enable nShutdown gpio from the system */
    736	kim_gdata->nshutdown = pdata->nshutdown_gpio;
    737	err = gpio_request(kim_gdata->nshutdown, "kim");
    738	if (unlikely(err)) {
    739		pr_err(" gpio %d request failed ", kim_gdata->nshutdown);
    740		goto err_sysfs_group;
    741	}
    742
    743	/* Configure nShutdown GPIO as output=0 */
    744	err = gpio_direction_output(kim_gdata->nshutdown, 0);
    745	if (unlikely(err)) {
    746		pr_err(" unable to configure gpio %d", kim_gdata->nshutdown);
    747		goto err_sysfs_group;
    748	}
    749	/* get reference of pdev for request_firmware */
    750	kim_gdata->kim_pdev = pdev;
    751	init_completion(&kim_gdata->kim_rcvd);
    752	init_completion(&kim_gdata->ldisc_installed);
    753
    754	err = sysfs_create_group(&pdev->dev.kobj, &uim_attr_grp);
    755	if (err) {
    756		pr_err("failed to create sysfs entries");
    757		goto err_sysfs_group;
    758	}
    759
    760	/* copying platform data */
    761	strncpy(kim_gdata->dev_name, pdata->dev_name, UART_DEV_NAME_LEN);
    762	kim_gdata->flow_cntrl = pdata->flow_cntrl;
    763	kim_gdata->baud_rate = pdata->baud_rate;
    764	pr_info("sysfs entries created\n");
    765
    766	kim_debugfs_dir = debugfs_create_dir("ti-st", NULL);
    767
    768	debugfs_create_file("version", S_IRUGO, kim_debugfs_dir,
    769				kim_gdata, &version_fops);
    770	debugfs_create_file("protocols", S_IRUGO, kim_debugfs_dir,
    771				kim_gdata, &list_fops);
    772	return 0;
    773
    774err_sysfs_group:
    775	st_core_exit(kim_gdata->core_data);
    776
    777err_core_init:
    778	kfree(kim_gdata);
    779
    780	return err;
    781}
    782
    783static int kim_remove(struct platform_device *pdev)
    784{
    785	/* free the GPIOs requested */
    786	struct ti_st_plat_data	*pdata = pdev->dev.platform_data;
    787	struct kim_data_s	*kim_gdata;
    788
    789	kim_gdata = platform_get_drvdata(pdev);
    790
    791	/*
    792	 * Free the Bluetooth/FM/GPIO
    793	 * nShutdown gpio from the system
    794	 */
    795	gpio_free(pdata->nshutdown_gpio);
    796	pr_info("nshutdown GPIO Freed");
    797
    798	debugfs_remove_recursive(kim_debugfs_dir);
    799	sysfs_remove_group(&pdev->dev.kobj, &uim_attr_grp);
    800	pr_info("sysfs entries removed");
    801
    802	kim_gdata->kim_pdev = NULL;
    803	st_core_exit(kim_gdata->core_data);
    804
    805	kfree(kim_gdata);
    806	kim_gdata = NULL;
    807	return 0;
    808}
    809
    810static int kim_suspend(struct platform_device *pdev, pm_message_t state)
    811{
    812	struct ti_st_plat_data	*pdata = pdev->dev.platform_data;
    813
    814	if (pdata->suspend)
    815		return pdata->suspend(pdev, state);
    816
    817	return 0;
    818}
    819
    820static int kim_resume(struct platform_device *pdev)
    821{
    822	struct ti_st_plat_data	*pdata = pdev->dev.platform_data;
    823
    824	if (pdata->resume)
    825		return pdata->resume(pdev);
    826
    827	return 0;
    828}
    829
    830/**********************************************************************/
    831/* entry point for ST KIM module, called in from ST Core */
    832static struct platform_driver kim_platform_driver = {
    833	.probe = kim_probe,
    834	.remove = kim_remove,
    835	.suspend = kim_suspend,
    836	.resume = kim_resume,
    837	.driver = {
    838		.name = "kim",
    839	},
    840};
    841
    842module_platform_driver(kim_platform_driver);
    843
    844MODULE_AUTHOR("Pavan Savoy <pavan_savoy@ti.com>");
    845MODULE_DESCRIPTION("Shared Transport Driver for TI BT/FM/GPS combo chips ");
    846MODULE_LICENSE("GPL");