/*
* 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>
#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
*/
void validate_firmware_response(struct kim_data_s *kim_gdata)
{
struct sk_buff *skb = kim_gdata->rx_skb;
if (unlikely(skb->data[5] != 0)) {
pr_err("no proper response during fw download");
pr_err("data6 %x", skb->data[5]);
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
*/
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);
memcpy(skb_put(kim_gdata->rx_skb, len), 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 };
pr_debug("%s", __func__);
INIT_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;
}
if (!wait_for_completion_timeout
(&kim_gdata->kim_rcvd, msecs_to_jiffies(CMD_RESP_TIME))) {
pr_err(" waiting for ver info- timed out ");
return -ETIMEDOUT;
}
version =
MAKEWORD(kim_gdata->resp_buffer[13],
kim_gdata->resp_buffer[14]);
chip = (version & 0x7C00) >> 10;
min_ver = (version & 0x007F);
maj_ver = (version & 0x0380) >> 7;
if (version & 0x8000)
maj_ver |= 0x0008;
sprintf(bts_scr_name, "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;
}
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 *)nxt_action)->size;
*len = *len - (sizeof(struct bts_action) +
((struct bts_action *)nxt_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[30] = { 0 }; /* 30 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 */
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;
}
/*
* 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 */
if (!wait_for_completion_timeout
(&kim_gdata->kim_rcvd,
msecs_to_jiffies(CMD_RESP_TIME))) {
pr_err("response timeout during fw download ");
/* timed out */
release_firmware(kim_gdata->fw_entry);
return -ETIMEDOUT;
}
INIT_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;
/* copy to local buffer */
if (unlikely(data[4] == 0x01 && data[5] == 0x10 && data[0] == 0x04)) {
/* must be the read_ver_cmd */
memcpy(kim_gdata->resp_buffer, data, count);
complete_all(&kim_gdata->kim_rcvd);
return;
} else {
kim_int_recv(kim_gdata, data, count);
/* either completes or times out */
}
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 kim_data_s *kim_gdata = (struct kim_data_s *)kim_data;
pr_info(" %s", __func__);
do {
/* Configure BT nShutdown to HIGH state */
gpio_set_value(kim_gdata->nshutdown, GPIO_LOW);
mdelay(5); /* FIXME: a proper toggle */
gpio_set_value(kim_gdata->nshutdown, GPIO_HIGH);
mdelay(100);
/* re-initialize the completion */
INIT_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_timeout(&kim_gdata->ldisc_installed,
msecs_to_jiffies(LDISC_TIME));
if (!err) { /* timeout */
pr_err("line disc installation timed out ");
kim_gdata->ldisc_install = 0;
pr_info("ldisc_install = 0");
sysfs_notify(&kim_gdata->kim_pdev->dev.kobj,
NULL, "install");
err = -ETIMEDOUT;
continue;
} else {
/* ldisc installed now */
pr_info(" line discipline installed ");
err = download_firmware(kim_gdata);
if (err != 0) {
pr_err("download firmware failed");
kim_gdata->ldisc_install = 0;
pr_info("ldisc_install = 0");
sysfs_notify(&kim_gdata->kim_pdev->dev.kobj,
NULL, "install");
continue;
} else { /* on success don't retry */
break;
}
}
} while (retry--);
return err;
}
/**
* st_kim_stop - called from ST Core, on the last un-registration
* toggle low the chip enable gpio
*/
long st_kim_stop(void *kim_data)
{
long err = 0;
struct kim_data_s *kim_gdata = (struct kim_data_s *)kim_data;
INIT_COMPLETION(kim_gdata->ldisc_installed);
/* Flush any pending characters in the driver and discipline. */
tty_ldisc_flush(kim_gdata->core_data->tty);
tty_driver_flush_buffer(kim_gdata->core_data->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_timeout(&kim_gdata->ldisc_installed,
msecs_to_jiffies(LDISC_TIME));
if (!err) { /* timeout */
pr_err(" timed out waiting for ldisc to be un-installed");
return -ETIMEDOUT;
}
/* By default configure BT nShutdown to LOW state */
gpio_set_value(kim_gdata->nshutdown, GPIO_LOW);
mdelay(1);
gpio_set_value(kim_gdata->nshutdown, GPIO_HIGH);
mdelay(1);
gpio_set_value(kim_gdata->nshutdown, GPIO_LOW);
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);
}
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, "%ld\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 =
__ATTR(dev_name, 0444, (void *)show_dev_name, NULL);
static struct kobj_attribute uart_baud_rate =
__ATTR(baud_rate, 0444, (void *)show_baud_rate, NULL);
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 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);
kim_gdata = dev_get_drvdata(&pdev->dev);
*core_data = kim_gdata->core_data;
}
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
*/
struct dentry *kim_debugfs_dir;
static int kim_probe(struct platform_device *pdev)
{
long status;
struct kim_data_s *kim_gdata;
struct ti_st_plat_data *pdata = pdev->dev.platform_data;
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;
}
dev_set_drvdata(&pdev->dev, kim_gdata);
status = st_core_init(&kim_gdata->core_data);
if (status != 0) {
pr_err(" ST core init failed");
return -EIO;
}
/* 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;
status = gpio_request(kim_gdata->nshutdown, "kim");
if (unlikely(status)) {
pr_err(" gpio %ld request failed ", kim_gdata->nshutdown);
return status;
}
/* Configure nShutdown GPIO as output=0 */
status = gpio_direction_output(kim_gdata->nshutdown, 0);
if (unlikely(status)) {
pr_err(" unable to configure gpio %ld", kim_gdata->nshutdown);
return status;
}
/* get reference of pdev for request_firmware
*/
kim_gdata->kim_pdev = pdev;
init_completion(&kim_gdata->kim_rcvd);
init_completion(&kim_gdata->ldisc_installed);
status = sysfs_create_group(&pdev->dev.kobj, &uim_attr_grp);
if (status) {
pr_err("failed to create sysfs entries");
return status;
}
/* 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 (IS_ERR(kim_debugfs_dir)) {
pr_err(" debugfs entries creation failed ");
kim_debugfs_dir = NULL;
return -EIO;
}
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);
pr_info(" debugfs entries created ");
return 0;
}
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 = dev_get_drvdata(&pdev->dev);
/* 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;
}
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 -EOPNOTSUPP;
}
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 -EOPNOTSUPP;
}
/**********************************************************************/
/* 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",
.owner = THIS_MODULE,
},
};
static int __init st_kim_init(void)
{
return platform_driver_register(&kim_platform_driver);
}
static void __exit st_kim_deinit(void)
{
platform_driver_unregister(&kim_platform_driver);
}
module_init(st_kim_init);
module_exit(st_kim_deinit);
MODULE_AUTHOR("Pavan Savoy <pavan_savoy@ti.com>");
MODULE_DESCRIPTION("Shared Transport Driver for TI BT/FM/GPS combo chips ");
MODULE_LICENSE("GPL");
