drivers:staging: sources for ST core
in [Kernel]
|
Prev: [PATCH] rcu: more careful check for the last non-dyntick-idle CPU
Next: [PATCH -v10 00/29] use lmb with x86
From: Alan Cox on 30 Mar 2010 07:20 > +/* all debug macros go in here */ > +#define ST_DRV_ERR(fmt, arg...) printk(KERN_ERR "(stc):"fmt"\n" , ## arg) > +#if defined(DEBUG) /* limited debug messages */ > +#define ST_DRV_DBG(fmt, arg...) printk(KERN_INFO "(stc):"fmt"\n" , ## arg) > +#define ST_DRV_VER(fmt, arg...) > +#elif defined(VERBOSE) /* very verbose */ > +#define ST_DRV_DBG(fmt, arg...) printk(KERN_INFO "(stc):"fmt"\n" , ## arg) > +#define ST_DRV_VER(fmt, arg...) printk(KERN_INFO "(stc):"fmt"\n" , ## arg) > +#else /* error msgs only */ > +#define ST_DRV_DBG(fmt, arg...) > +#define ST_DRV_VER(fmt, arg...) > +#endif As Greg said earlier - needs to be using the standard debug macros > +/* > + * local data instances > + */ > +static struct st_data_s *st_gdata; > +/* function pointer pointing to either, > + * st_kim_recv during registration to receive fw download responses > + * st_int_recv after registration to receive proto stack responses > + */ > +void (*st_recv) (const unsigned char *data, long count); Need some form of context so you can have multiple device instances and avoid games with globals (which always end up in pain) > + > +/********************************************************************/ > +/* internal misc functions */ > +bool is_protocol_list_empty(void) > +{ > + unsigned char i = 0; > + ST_DRV_DBG(" %s ", __func__); > + for (i = 0; i < ST_MAX; i++) { > + if (st_gdata->list[i] != NULL) > + return ST_NOTEMPTY; > + /* not empty */ > + } > + /* list empty */ > + return ST_EMPTY; Why not just keep a count of entries you've added/removed ? > + * This is the internal write function - a wrapper > + * to tty->ops->write > + */ > +int st_int_write(const unsigned char *data, int count) > +{ > +#ifdef VERBOSE /* for debug */ > + int i; > +#endif > + struct tty_struct *tty; > + if (unlikely(st_gdata == NULL || st_gdata->tty == NULL)) { > + ST_DRV_ERR("tty unavailable to perform write"); You need to use the tty pointer passed, you don't want to walk tty->something and back because you may race a hangup. Plus you would need to manage the krefs (object references) > + return ST_ERR_FAILURE; Should be using Linux error codes for upstream. A global search/replace of the ST_ERR_xxx for a similar -Efoo code will do the trick I think > +/* > + * push the skb received to relevant > + * protocol stacks > + */ > +void st_send_frame(enum proto_type protoid, struct sk_buff *skb) > +{ > + ST_DRV_DBG(" %s(prot:%d) ", __func__, protoid); > + > + if (unlikely > + (st_gdata == NULL || skb == NULL > + || st_gdata->list[protoid] == NULL)) { > + ST_DRV_ERR("protocol %d not registered, no data to send?", > + protoid); > + kfree_skb(skb); > + return; > + } What is the locking rule to ensure I don't unregister a protocol as send frame is called ? > + * to call registration complete callbacks > + * of all protocol stack drivers > + */ > +void st_reg_complete(char err) > +{ > + unsigned char i = 0; > + ST_DRV_DBG(" %s ", __func__); > + for (i = 0; i < ST_MAX; i++) { > + if (likely(st_gdata != NULL && st_gdata->list[i] != NULL && Except on very hot paths that go odd ways likely and unlikely are normally a loss. > +static inline int st_check_data_len(int protoid, int len) > +{ > + register int room = skb_tailroom(st_gdata->rx_skb); No need to use register - gcc is generally smarter than humans here, especially in the long term. You may optimise perfectly for a single cpu/compiler revision but not for all > +/* Decodes received RAW data and forwards to corresponding > + * client drivers (Bluetooth,FM,GPS..etc). > + * > + */ > +void st_int_recv(const unsigned char *data, long count) There are lots of globals here, in part it seems due to the lack of any kind of context being passed around > > + /* this function can be invoked in more then one context. > + * so have a lock */ It's a good idea to document what data is locked and what the data locking assumptions are. I'm finding that part of the code quite hard to follow > +/* > + * internal wakeup function > + * called from either > + * - TTY layer when write's finished > + * - st_write (in context of the protocol stack) > + */ > +void st_tx_wakeup(struct st_data_s *st_data) > + while ((skb = st_int_dequeue(st_data))) { Called in two paths but st_int_dequeue seems to have no internal locking > +/* functions called from ST KIM > +*/ > +void kim_st_list_protocols(char *buf) > +{ > + unsigned long flags = 0; > +#ifdef DEBUG > + unsigned char i = ST_MAX; > +#endif > + spin_lock_irqsave(&st_gdata->lock, flags); > +#ifdef DEBUG /* more detailed log */ > + for (i = 0; i < ST_MAX; i++) { > + if (i == 0) { > + sprintf(buf, "%s is %s", protocol_strngs[i], > + st_gdata->list[i] != > + NULL ? "Registered" : "Unregistered"); Always a good idea to use snprintf and track size (plus pass buffer size) it avoida accidents later. Or also see the seq_ interface when you want to build proc type files. > +/********************************************************************/ > +/* > + * functions called from protocol stack drivers > + * to be EXPORT-ed > + */ > +long st_register(struct st_proto_s *new_proto) > +{ > + long err = ST_SUCCESS; > > + * functions called from TTY layer > + */ > +static int st_tty_open(struct tty_struct *tty) > +{ > + int err = ST_SUCCESS; > + ST_DRV_DBG("%s ", __func__); > + > + st_gdata->tty = tty; If you do this you need to use krefs and manage the reference properly over open/close/hangup > +static void st_tty_close(struct tty_struct *tty) > +{ > + /* Flush any pending characters in the driver and discipline. */ > + tty_driver_flush_buffer(tty); Close will deal with this anyway > +static void st_tty_receive(struct tty_struct *tty, const unsigned char *data, > + char *tty_flags, int count) > +{ > +#ifdef VERBOSE > + long i; > + printk(KERN_ERR "incoming data...\n"); > + for (i = 0; i < count; i++) > + printk(" %x", data[i]); > + printk(KERN_ERR "\n.. data end\n"); > +#endif > + > + /* > + * if fw download is in progress then route incoming data > + * to KIM for validation > + */ > + st_recv(data, count); If you passed tty up and used tty->disc_data you'd be able to handle multiple devices > +/********************************************************************/ > +static int __init st_core_init(void) > +{ > + long err; > + static struct tty_ldisc_ops *st_ldisc_ops; > + > + /* populate and register to TTY line discipline */ > + st_ldisc_ops = kzalloc(sizeof(*st_ldisc_ops), GFP_KERNEL); > + if (!st_ldisc_ops) { > + ST_DRV_ERR("no mem to allocate"); > + return -ENOMEM; > + } > + > + st_ldisc_ops->magic = TTY_LDISC_MAGIC; > + st_ldisc_ops->name = "n_st"; /*"n_hci"; */ > + st_ldisc_ops->open = st_tty_open; > + st_ldisc_ops->close = st_tty_close; > + st_ldisc_ops->receive_buf = st_tty_receive; > + st_ldisc_ops->write_wakeup = st_tty_wakeup; > + st_ldisc_ops->flush_buffer = st_tty_flush_buffer; > + st_ldisc_ops->owner = THIS_MODULE; You could just declare this as a static struct like other drivers do ? -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo(a)vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
From: Pavan Savoy on 30 Mar 2010 12:00 Alan, --- On Tue, 30/3/10, Alan Cox <alan(a)lxorguk.ukuu.org.uk> wrote: > From: Alan Cox <alan(a)lxorguk.ukuu.org.uk> > Subject: Re: [PATCH] drivers:staging: sources for ST core > To: pavan_savoy(a)ti.com > Cc: marcel(a)holtmann.org, gregkh(a)suse.de, linux-kernel(a)vger.kernel.org, pavan_savoy(a)yahoo.co.in > Date: Tuesday, 30 March, 2010, 4:52 PM > > +/* all debug macros go in here > */ > > +#define ST_DRV_ERR(fmt, arg...)� printk(KERN_ERR > "(stc):"fmt"\n" , ## arg) > > +#if defined(DEBUG)��� > ��� /* limited debug messages */ > > +#define ST_DRV_DBG(fmt, arg...)� > printk(KERN_INFO "(stc):"fmt"\n" , ## arg) > > +#define ST_DRV_VER(fmt, arg...) > > +#elif defined(VERBOSE)��� > ��� /* very verbose */ > > +#define ST_DRV_DBG(fmt, arg...)� > printk(KERN_INFO "(stc):"fmt"\n" , ## arg) > > +#define ST_DRV_VER(fmt, arg...)� > printk(KERN_INFO "(stc):"fmt"\n" , ## arg) > > +#else /* error msgs only */ > > +#define ST_DRV_DBG(fmt, arg...) > > +#define ST_DRV_VER(fmt, arg...) > > +#endif > > As Greg said earlier - needs to be using the standard debug > macros Agree - It's all there because of the organization's coding standards. Will correct it. > > > +/* > > + * local data instances > > + */ > > +static struct st_data_s *st_gdata; > > +/* function pointer pointing to either, > > + * st_kim_recv during registration to receive fw > download responses > > + * st_int_recv after registration to receive proto > stack responses > > + */ > > +void (*st_recv) (const unsigned char *data, long > count); > > Need some form of context so you can have multiple device > instances and > avoid games with globals (which always end up in pain) Yes, platform device context ? as in per-device ? However, would face a problem (as mentioned in other mail) - which is when a BT/FM driver which are like client drivers want to use this line discipline, do they need to know which context this needs to go into ? > > + > > > +/********************************************************************/ > > +/* internal misc functions */ > > +bool is_protocol_list_empty(void) > > +{ > > +��� unsigned char i = 0; > > +��� ST_DRV_DBG(" %s ", __func__); > > +��� for (i = 0; i < ST_MAX; i++) { > > +��� ��� if > (st_gdata->list[i] != NULL) > > +��� ��� > ��� return ST_NOTEMPTY; > > +��� ��� /* not empty > */ > > +��� } > > +��� /* list empty */ > > +��� return ST_EMPTY; > > Why not just keep a count of entries you've added/removed > ? One more variable ? to st_gdata ? done. Sounds simple. > > > + *� This is the internal write function - a > wrapper > > + *� to tty->ops->write > > + */ > > +int st_int_write(const unsigned char *data, int > count) > > +{ > > +#ifdef VERBOSE��� ��� > ��� /* for debug */ > > +��� int i; > > +#endif > > +��� struct tty_struct *tty; > > +��� if (unlikely(st_gdata == NULL || > st_gdata->tty == NULL)) { > > +��� ��� ST_DRV_ERR("tty > unavailable to perform write"); > > You need to use the tty pointer passed, you don't want to > walk > tty->something and back because you may race a hangup. > Plus you would > need to manage the krefs (object references) Do I need to do it in tty_open and _release ? Because I don't have anything much to release when tty closes. All I have to do is done in tty_close. > > +��� ��� return > ST_ERR_FAILURE; > > Should be using Linux error codes for upstream. A global > search/replace > of the ST_ERR_xxx for a similar -Efoo code will do the > trick I think Ok, But is it ok, to maintain codes, internally among ST/BT/FM drivers ? > > +/* > > + * push the skb received to relevant > > + * protocol stacks > > + */ > > +void st_send_frame(enum proto_type protoid, struct > sk_buff *skb) > > +{ > > +��� ST_DRV_DBG(" %s(prot:%d) ", > __func__, protoid); > > + > > +��� if (unlikely > > +��� � � (st_gdata == NULL || > skb == NULL > > +��� � ���|| > st_gdata->list[protoid] == NULL)) { > > +��� ��� > ST_DRV_ERR("protocol %d not registered, no data to send?", > > +��� ��� > ��� ���protoid); > > +��� ��� > kfree_skb(skb); > > +��� ��� return; > > +��� } > > What is the locking rule to ensure I don't unregister a > protocol as send > frame is called ? send_frame is called from st_int_recv - which is a SOFT-IRQ I believe, So do I really need that ? > > > + * to call registration complete callbacks > > + * of all protocol stack drivers > > + */ > > +void st_reg_complete(char err) > > +{ > > +��� unsigned char i = 0; > > +��� ST_DRV_DBG(" %s ", __func__); > > +��� for (i = 0; i < ST_MAX; i++) { > > +��� ��� if > (likely(st_gdata != NULL && st_gdata->list[i] != > NULL && > > Except on very hot paths that go odd ways likely and > unlikely are > normally a loss. point taken. > > > +static inline int st_check_data_len(int protoid, int > len) > > +{ > > +��� register int room = > skb_tailroom(st_gdata->rx_skb); > > No need to use register - gcc is generally smarter than > humans here, > especially in the long term. You may optimise perfectly for > a single > cpu/compiler revision but not for all Ha, this one's a copy/paste piece from hci_ll.c's recv function. > > > +/* Decodes received RAW data and forwards to > corresponding > > + * client drivers (Bluetooth,FM,GPS..etc). > > + * > > + */ > > +void st_int_recv(const unsigned char *data, long > count) > > There are lots of globals here, in part it seems due to the > lack of any > kind of context being passed around > This global function pointer as such is not a necessity. st_recv can point to st_kim_recv (response to firmware download) or st_int_recv (response to commands). They are sort of mutually exclusive, firmware will be downloaded once. and once ready, chip will always use cmd/response st_int_recv. > > > > > +��� /* this function can be invoked in > more then one context. > > +�����* so have a lock */ > > It's a good idea to document what data is locked and what > the data > locking assumptions are. I'm finding that part of the code > quite hard to > follow Ok. > > > +/* > > + * internal wakeup function > > + * called from either > > + * - TTY layer when write's finished > > + * - st_write (in context of the protocol stack) > > + */ > > +void st_tx_wakeup(struct st_data_s *st_data) > > > > +��� ��� while ((skb = > st_int_dequeue(st_data))) { > > Called in two paths but st_int_dequeue seems to have no > internal locking The 2nd path doesn't come until the int_dequeue at all, i.e it would know ST_TX_SENDING, and would queue the skb and return. I remember there was one lock here, removed when I started to have problem on SMP. > > > +/* functions called from ST KIM > > +*/ > > +void kim_st_list_protocols(char *buf) > > +{ > > +��� unsigned long flags = 0; > > +#ifdef DEBUG > > +��� unsigned char i = ST_MAX; > > +#endif > > +��� > spin_lock_irqsave(&st_gdata->lock, flags); > > +#ifdef DEBUG��� ��� > ��� /* more detailed log */ > > +��� for (i = 0; i < ST_MAX; i++) { > > +��� ��� if (i == 0) { > > +��� ��� > ��� sprintf(buf, "%s is %s", > protocol_strngs[i], > > +��� ��� > ��� ��� st_gdata->list[i] > != > > +��� ��� > ��� ��� NULL ? "Registered" : > "Unregistered"); > > Always a good idea to use snprintf and track size (plus > pass buffer size) > it avoida accidents later. Or also see the seq_ interface > when you want > to build proc type files. Ok, the whole thing will go off. The plan is to use /dev/rfkill and avoid the sysfs entry altogether. > > > +/********************************************************************/ > > +/* > > + * functions called from protocol stack drivers > > + * to be EXPORT-ed > > + */ > > +long st_register(struct st_proto_s *new_proto) > > +{ > > +��� long err = ST_SUCCESS; > > > > > + * functions called from TTY layer > > + */ > > +static int st_tty_open(struct tty_struct *tty) > > +{ > > +��� int err = ST_SUCCESS; > > +��� ST_DRV_DBG("%s ", __func__); > > + > > +��� st_gdata->tty = tty; > > If you do this you need to use krefs and manage the > reference properly > over open/close/hangup ok, But can I really put the kref upon tty_close ? A bluetooth driver, might have registered, but wouldn't have started communication i.e tty_open might not have occurred. So, I wouldn't have any trouble with that right ? > > > +static void st_tty_close(struct tty_struct *tty) > > +{ > > +��� /* Flush any pending characters in > the driver and discipline. */ > > > +��� tty_driver_flush_buffer(tty); > > Close will deal with this anyway yep, redundant - will remove it. > > > +static void st_tty_receive(struct tty_struct *tty, > const unsigned char *data, > > +��� ��� > ��� ���char *tty_flags, int > count) > > +{ > > +#ifdef VERBOSE > > +��� long i; > > +��� printk(KERN_ERR "incoming > data...\n"); > > +��� for (i = 0; i < count; i++) > > +��� ��� printk(" %x", > data[i]); > > +��� printk(KERN_ERR "\n.. data > end\n"); > > +#endif > > + > > +��� /* > > +�����* if fw download is in > progress then route incoming data > > +�����* to KIM for > validation > > +�����*/ > > +��� st_recv(data, count); > > If you passed tty up and used tty->disc_data you'd be > able to handle > multiple devices Ok, the only problem here is st_int_write, which is called during firmware download. I don't get a tty there, and hence I copy it onto the st_gdata->tty. For the rest of callbacks from TTY layer, I can make use of the tty coming into the function. Considering the other way, if st_gdata went into the tty->disc_data, I have EXPORTED functions like st_register and st_unregister, when I can't get hold of the disc_data. > > > +/********************************************************************/ > > +static int __init st_core_init(void) > > +{ > > +��� long err; > > +��� static struct tty_ldisc_ops > *st_ldisc_ops; > > + > > +��� /* populate and register to TTY > line discipline */ > > +��� st_ldisc_ops = > kzalloc(sizeof(*st_ldisc_ops), GFP_KERNEL); > > +��� if (!st_ldisc_ops) { > > +��� ��� ST_DRV_ERR("no > mem to allocate"); > > +��� ��� return > -ENOMEM; > > +��� } > > + > > +��� st_ldisc_ops->magic = > TTY_LDISC_MAGIC; > > +��� st_ldisc_ops->name = > "n_st";��� /*"n_hci"; */ > > +��� st_ldisc_ops->open = > st_tty_open; > > +��� st_ldisc_ops->close = > st_tty_close; > > +��� st_ldisc_ops->receive_buf = > st_tty_receive; > > +��� st_ldisc_ops->write_wakeup = > st_tty_wakeup; > > +��� st_ldisc_ops->flush_buffer = > st_tty_flush_buffer; > > +��� st_ldisc_ops->owner = > THIS_MODULE; > > You could just declare this as a static struct like other > drivers do ? > Yep, I remember doing that, and using a couple of goto-s as well. Organization coding standards and linux Coding Style collided. - Will do that. The INTERNET now has a personality. YOURS! See your Yahoo! Homepage. http://in.yahoo.com/ -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo(a)vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
From: Greg KH on 30 Mar 2010 16:40 On Tue, Mar 30, 2010 at 09:23:23PM +0530, Pavan Savoy wrote: > Alan, > > --- On Tue, 30/3/10, Alan Cox <alan(a)lxorguk.ukuu.org.uk> wrote: > > > From: Alan Cox <alan(a)lxorguk.ukuu.org.uk> > > Subject: Re: [PATCH] drivers:staging: sources for ST core > > To: pavan_savoy(a)ti.com > > Cc: marcel(a)holtmann.org, gregkh(a)suse.de, linux-kernel(a)vger.kernel.org, pavan_savoy(a)yahoo.co.in > > Date: Tuesday, 30 March, 2010, 4:52 PM > > > +/* all debug macros go in here > > */ > > > +#define ST_DRV_ERR(fmt, arg...)? printk(KERN_ERR > > "(stc):"fmt"\n" , ## arg) > > > +#if defined(DEBUG)??? > > ??? /* limited debug messages */ > > > +#define ST_DRV_DBG(fmt, arg...)? > > printk(KERN_INFO "(stc):"fmt"\n" , ## arg) > > > +#define ST_DRV_VER(fmt, arg...) > > > +#elif defined(VERBOSE)??? > > ??? /* very verbose */ > > > +#define ST_DRV_DBG(fmt, arg...)? > > printk(KERN_INFO "(stc):"fmt"\n" , ## arg) > > > +#define ST_DRV_VER(fmt, arg...)? > > printk(KERN_INFO "(stc):"fmt"\n" , ## arg) > > > +#else /* error msgs only */ > > > +#define ST_DRV_DBG(fmt, arg...) > > > +#define ST_DRV_VER(fmt, arg...) > > > +#endif > > > > As Greg said earlier - needs to be using the standard debug > > macros > > Agree - It's all there because of the organization's coding standards. > Will correct it. Might you also want to correct your organization's coding standards to follow the correct Linux kernel ones? That way you will not have this problem in the future. thanks, greg k-h -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo(a)vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
From: Pavan Savoy on 30 Mar 2010 17:10 --- On Wed, 31/3/10, Greg KH <gregkh(a)suse.de> wrote: > From: Greg KH <gregkh(a)suse.de> > Subject: Re: [PATCH] drivers:staging: sources for ST core > To: "Pavan Savoy" <pavan_savoy(a)ti.com> > Cc: "Alan Cox" <alan(a)lxorguk.ukuu.org.uk>, marcel(a)holtmann.org, linux-kernel(a)vger.kernel.org > Date: Wednesday, 31 March, 2010, 2:08 AM > On Tue, Mar 30, 2010 at 09:23:23PM > +0530, Pavan Savoy wrote: > > Alan, > > > > --- On Tue, 30/3/10, Alan Cox <alan(a)lxorguk.ukuu.org.uk> > wrote: > > > > > From: Alan Cox <alan(a)lxorguk.ukuu.org.uk> > > > Subject: Re: [PATCH] drivers:staging: sources for > ST core > > > To: pavan_savoy(a)ti.com > > > Cc: marcel(a)holtmann.org, > gregkh(a)suse.de, linux-kernel(a)vger.kernel.org, > pavan_savoy(a)yahoo.co.in > > > Date: Tuesday, 30 March, 2010, 4:52 PM > > > > +/* all debug macros go in here > > > */ > > > > +#define ST_DRV_ERR(fmt, arg...)? > printk(KERN_ERR > > > "(stc):"fmt"\n" , ## arg) > > > > +#if defined(DEBUG)??? > > > ??? /* limited debug messages */ > > > > +#define ST_DRV_DBG(fmt, arg...)? > > > printk(KERN_INFO "(stc):"fmt"\n" , ## arg) > > > > +#define ST_DRV_VER(fmt, arg...) > > > > +#elif defined(VERBOSE)??? > > > ??? /* very verbose */ > > > > +#define ST_DRV_DBG(fmt, arg...)? > > > printk(KERN_INFO "(stc):"fmt"\n" , ## arg) > > > > +#define ST_DRV_VER(fmt, arg...)? > > > printk(KERN_INFO "(stc):"fmt"\n" , ## arg) > > > > +#else /* error msgs only */ > > > > +#define ST_DRV_DBG(fmt, arg...) > > > > +#define ST_DRV_VER(fmt, arg...) > > > > +#endif > > > > > > As Greg said earlier - needs to be using the > standard debug > > > macros > > > > Agree - It's all there because of the organization's > coding standards. > > Will correct it. > > Might you also want to correct your organization's coding > standards to > follow the correct Linux kernel ones?� That way you > will not have this > problem in the future. > > thanks, > > greg k-h So, something like the below is ok, I have defined my own pr_fmt, however default log level on my board is 7, and hence pr_info is a bit more annoying than usual. So all verbose or debug messages including the data in/out of the UART are pr_debug. From 67bdf81bb0a60e2c76a139dc4d39208eaa03bcae Mon Sep 17 00:00:00 2001 From: Pavan Savoy <pavan_savoy(a)ti.com> Date: Mon, 22 Mar 2010 13:18:31 -0400 Subject: [PATCH] drivers:staging: sources for ST core Texas Instruments BT, FM and GPS combo chips/drivers make use of a single TTY to communicate with the chip. This module constitutes the core logic, TTY ldisc driver and the exported symbols for registering/unregistering of the protocol drivers such as BT/FM/GPS. Signed-off-by: Pavan Savoy <pavan_savoy(a)ti.com> --- drivers/staging/ti-st/st_core.c | 1045 +++++++++++++++++++++++++++++++++++++++ drivers/staging/ti-st/st_core.h | 92 ++++ 2 files changed, 1137 insertions(+), 0 deletions(-) create mode 100644 drivers/staging/ti-st/st_core.c create mode 100644 drivers/staging/ti-st/st_core.h diff --git a/drivers/staging/ti-st/st_core.c b/drivers/staging/ti-st/st_core.c new file mode 100644 index 0000000..50fea1e --- /dev/null +++ b/drivers/staging/ti-st/st_core.c @@ -0,0 +1,1045 @@ +/* + * Shared Transport Line discipline driver Core + * This hooks up ST KIM driver and ST LL driver + * Copyright (C) 2009 Texas Instruments + * + * 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) "(stc): " fmt +#include <linux/module.h> +#include <linux/kernel.h> +#include <linux/init.h> +#include <linux/tty.h> + +/* understand BT, FM and GPS for now */ +#include <net/bluetooth/bluetooth.h> +#include <net/bluetooth/hci_core.h> +#include <net/bluetooth/hci.h> +#include "fm.h" +/* + * packet formats for fm and gps + * #include "gps.h" + */ +#include "st_core.h" +#include "st_kim.h" +#include "st_ll.h" +#include "st.h" + +#ifdef DEBUG +/* strings to be used for rfkill entries and by + * ST Core to be used for sysfs debug entry + */ +#define PROTO_ENTRY(type, name) name +const unsigned char *protocol_strngs[] = { + PROTO_ENTRY(ST_BT, "Bluetooth"), + PROTO_ENTRY(ST_FM, "FM"), + PROTO_ENTRY(ST_GPS, "GPS"), +}; +#endif +/* + * local data instances + */ +static struct st_data_s *st_gdata; +/* function pointer pointing to either, + * st_kim_recv during registration to receive fw download responses + * st_int_recv after registration to receive proto stack responses + */ +void (*st_recv) (const unsigned char *data, long count); + +/********************************************************************/ +/* internal misc functions */ +bool is_protocol_list_empty(void) +{ + unsigned char i = 0; + pr_debug(" %s ", __func__); + for (i = 0; i < ST_MAX; i++) { + if (st_gdata->list[i] != NULL) + return ST_NOTEMPTY; + /* not empty */ + } + /* list empty */ + return ST_EMPTY; +} + +/* can be called in from + * -- KIM (during fw download) + * -- ST Core (during st_write) + * + * This is the internal write function - a wrapper + * to tty->ops->write + */ +int st_int_write(const unsigned char *data, int count) +{ +#ifdef VERBOSE /* for debug */ + int i; +#endif + struct tty_struct *tty; + if (unlikely(st_gdata == NULL || st_gdata->tty == NULL)) { + pr_err("tty unavailable to perform write"); + return ST_ERR_FAILURE; + } + tty = st_gdata->tty; +#ifdef VERBOSE + printk(KERN_ERR "start data..\n"); + for (i = 0; i < count; i++) /* no newlines for each datum */ + printk(" %x", data[i]); + printk(KERN_ERR "\n ..end data\n"); +#endif + + return tty->ops->write(tty, data, count); + +} + +/* + * push the skb received to relevant + * protocol stacks + */ +void st_send_frame(enum proto_type protoid, struct sk_buff *skb) +{ + pr_debug(" %s(prot:%d) ", __func__, protoid); + + if (unlikely + (st_gdata == NULL || skb == NULL + || st_gdata->list[protoid] == NULL)) { + pr_err("protocol %d not registered, no data to send?", + protoid); + kfree_skb(skb); + return; + } + /* this cannot fail + * this shouldn't take long + * - should be just skb_queue_tail for the + * protocol stack driver + */ + if (likely(st_gdata->list[protoid]->recv != NULL)) { + if (unlikely(st_gdata->list[protoid]->recv(skb) + != ST_SUCCESS)) { + pr_err(" proto stack %d's ->recv failed", protoid); + kfree_skb(skb); + return; + } + } else { + pr_err(" proto stack %d's ->recv null", protoid); + kfree_skb(skb); + } + pr_debug(" done %s", __func__); + return; +} + +/* + * to call registration complete callbacks + * of all protocol stack drivers + */ +void st_reg_complete(char err) +{ + unsigned char i = 0; + pr_debug(" %s ", __func__); + for (i = 0; i < ST_MAX; i++) { + if (likely(st_gdata != NULL && st_gdata->list[i] != NULL && + st_gdata->list[i]->reg_complete_cb != NULL)) + st_gdata->list[i]->reg_complete_cb(err); + } +} + +static inline int st_check_data_len(int protoid, int len) +{ + register int room = skb_tailroom(st_gdata->rx_skb); + + pr_debug("len %d room %d", len, room); + + if (!len) { + /* Received packet has only packet header and + * has zero length payload. So, ask ST CORE to + * forward the packet to protocol driver (BT/FM/GPS) + */ + st_send_frame(protoid, st_gdata->rx_skb); + + } 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(st_gdata->rx_skb); + } else { + /* Packet header has non-zero payload length and + * we have enough space in created skb. Lets read + * payload data */ + st_gdata->rx_state = ST_BT_W4_DATA; + st_gdata->rx_count = len; + return len; + } + + /* Change ST state to continue to process next + * packet */ + st_gdata->rx_state = ST_W4_PACKET_TYPE; + st_gdata->rx_skb = NULL; + st_gdata->rx_count = 0; + + return 0; +} + +/* internal function for action when wake-up ack + * received + */ +static inline void st_wakeup_ack(unsigned char cmd) +{ + register struct sk_buff *waiting_skb; + unsigned long flags = 0; + + spin_lock_irqsave(&st_gdata->lock, flags); + /* de-Q from waitQ and Q in txQ now that the + * chip is awake + */ + while ((waiting_skb = skb_dequeue(&st_gdata->tx_waitq))) + skb_queue_tail(&st_gdata->txq, waiting_skb); + + /* state forwarded to ST LL */ + st_ll_sleep_state((unsigned long)cmd); + spin_unlock_irqrestore(&st_gdata->lock, flags); + + /* wake up to send the recently copied skbs from waitQ */ + st_tx_wakeup(st_gdata); +} + +/* Decodes received RAW data and forwards to corresponding + * client drivers (Bluetooth,FM,GPS..etc). + * + */ +void st_int_recv(const unsigned char *data, long count) +{ + register char *ptr; + struct hci_event_hdr *eh; + struct hci_acl_hdr *ah; + struct hci_sco_hdr *sh; + struct fm_event_hdr *fm; + struct gps_event_hdr *gps; + register int len = 0, type = 0, dlen = 0; + static enum proto_type protoid = ST_MAX; + + pr_debug("count %ld rx_state %ld" + "rx_count %ld", count, st_gdata->rx_state, + st_gdata->rx_count); + + ptr = (char *)data; + /* tty_receive sent null ? */ + if (unlikely(ptr == NULL)) { + pr_err(" received null from TTY "); + return; + } + + /* Decode received bytes here */ + while (count) { + if (st_gdata->rx_count) { + len = min_t(unsigned int, st_gdata->rx_count, count); + memcpy(skb_put(st_gdata->rx_skb, len), ptr, len); + st_gdata->rx_count -= len; + count -= len; + ptr += len; + + if (st_gdata->rx_count) + continue; + + /* Check ST RX state machine , where are we? */ + switch (st_gdata->rx_state) { + + /* Waiting for complete packet ? */ + case ST_BT_W4_DATA: + pr_debug("Complete pkt received"); + + /* Ask ST CORE to forward + * the packet to protocol driver */ + st_send_frame(protoid, st_gdata->rx_skb); + + st_gdata->rx_state = ST_W4_PACKET_TYPE; + st_gdata->rx_skb = NULL; + protoid = ST_MAX; /* is this required ? */ + continue; + + /* Waiting for Bluetooth event header ? */ + case ST_BT_W4_EVENT_HDR: + eh = (struct hci_event_hdr *)st_gdata->rx_skb-> + data; + + pr_debug("Event header: evt 0x%2.2x" + "plen %d", eh->evt, eh->plen); + + st_check_data_len(protoid, eh->plen); + continue; + + /* Waiting for Bluetooth acl header ? */ + case ST_BT_W4_ACL_HDR: + ah = (struct hci_acl_hdr *)st_gdata->rx_skb-> + data; + dlen = __le16_to_cpu(ah->dlen); + + pr_debug("ACL header: dlen %d", dlen); + + st_check_data_len(protoid, dlen); + continue; + + /* Waiting for Bluetooth sco header ? */ + case ST_BT_W4_SCO_HDR: + sh = (struct hci_sco_hdr *)st_gdata->rx_skb-> + data; + + pr_debug("SCO header: dlen %d", sh->dlen); + + st_check_data_len(protoid, sh->dlen); + continue; + case ST_FM_W4_EVENT_HDR: + fm = (struct fm_event_hdr *)st_gdata->rx_skb-> + data; + pr_debug("FM Header: "); + st_check_data_len(ST_FM, fm->plen); + continue; + /* TODO : Add GPS packet machine logic here */ + case ST_GPS_W4_EVENT_HDR: + /* [0x09 pkt hdr][R/W byte][2 byte len] */ + gps = (struct gps_event_hdr *)st_gdata->rx_skb-> + data; + pr_debug("GPS Header: "); + st_check_data_len(ST_GPS, gps->plen); + continue; + } /* end of switch rx_state */ + } + + /* end of if rx_count */ + /* Check first byte of packet and identify module + * owner (BT/FM/GPS) */ + switch (*ptr) { + + /* Bluetooth event packet? */ + case HCI_EVENT_PKT: + pr_debug("Event packet"); + st_gdata->rx_state = ST_BT_W4_EVENT_HDR; + st_gdata->rx_count = HCI_EVENT_HDR_SIZE; + type = HCI_EVENT_PKT; + protoid = ST_BT; + break; + + /* Bluetooth acl packet? */ + case HCI_ACLDATA_PKT: + pr_debug("ACL packet"); + st_gdata->rx_state = ST_BT_W4_ACL_HDR; + st_gdata->rx_count = HCI_ACL_HDR_SIZE; + type = HCI_ACLDATA_PKT; + protoid = ST_BT; + break; + + /* Bluetooth sco packet? */ + case HCI_SCODATA_PKT: + pr_debug("SCO packet"); + st_gdata->rx_state = ST_BT_W4_SCO_HDR; + st_gdata->rx_count = HCI_SCO_HDR_SIZE; + type = HCI_SCODATA_PKT; + protoid = ST_BT; + break; + + /* Channel 8(FM) packet? */ + case ST_FM_CH8_PKT: + pr_debug("FM CH8 packet"); + type = ST_FM_CH8_PKT; + st_gdata->rx_state = ST_FM_W4_EVENT_HDR; + st_gdata->rx_count = FM_EVENT_HDR_SIZE; + protoid = ST_FM; + break; + + /* Channel 9(GPS) packet? */ + case 0x9: /*ST_LL_GPS_CH9_PKT */ + pr_debug("GPS CH9 packet"); + type = 0x9; /* ST_LL_GPS_CH9_PKT; */ + protoid = ST_GPS; + st_gdata->rx_state = ST_GPS_W4_EVENT_HDR; + st_gdata->rx_count = 3; /* GPS_EVENT_HDR_SIZE -1*/ + break; + case LL_SLEEP_IND: + case LL_SLEEP_ACK: + case LL_WAKE_UP_IND: + /* this takes appropriate action based on + * sleep state received -- + */ + st_ll_sleep_state(*ptr); + ptr++; + count--; + continue; + case LL_WAKE_UP_ACK: + /* wake up ack received */ + st_wakeup_ack(*ptr); + ptr++; + count--; + continue; + /* Unknow packet? */ + default: + pr_err("Unknown packet type %2.2x", (__u8) *ptr); + ptr++; + count--; + continue; + }; + ptr++; + count--; + + switch (protoid) { + case ST_BT: + /* Allocate new packet to hold received data */ + st_gdata->rx_skb = + bt_skb_alloc(HCI_MAX_FRAME_SIZE, GFP_ATOMIC); + if (!st_gdata->rx_skb) { + pr_err("Can't allocate mem for new packet"); + st_gdata->rx_state = ST_W4_PACKET_TYPE; + st_gdata->rx_count = 0; + return; + } + bt_cb(st_gdata->rx_skb)->pkt_type = type; + break; + case ST_FM: /* for FM */ + st_gdata->rx_skb = + alloc_skb(FM_MAX_FRAME_SIZE, GFP_ATOMIC); + if (!st_gdata->rx_skb) { + pr_err("Can't allocate mem for new packet"); + st_gdata->rx_state = ST_W4_PACKET_TYPE; + st_gdata->rx_count = 0; + return; + } + /* place holder 0x08 */ + skb_reserve(st_gdata->rx_skb, 1); + st_gdata->rx_skb->cb[0] = ST_FM_CH8_PKT; + break; + case ST_GPS: + /* for GPS */ + st_gdata->rx_skb = + alloc_skb(100 /*GPS_MAX_FRAME_SIZE */ , GFP_ATOMIC); + if (!st_gdata->rx_skb) { + pr_err("Can't allocate mem for new packet"); + st_gdata->rx_state = ST_W4_PACKET_TYPE; + st_gdata->rx_count = 0; + return; + } + /* place holder 0x09 */ + skb_reserve(st_gdata->rx_skb, 1); + st_gdata->rx_skb->cb[0] = 0x09; /*ST_GPS_CH9_PKT; */ + break; + case ST_MAX: + break; + } + } + pr_debug("done %s", __func__); + return; +} + +/* internal de-Q function + * -- return previous in-completely written skb + * or return the skb in the txQ + */ +struct sk_buff *st_int_dequeue(struct st_data_s *st_data) +{ + struct sk_buff *returning_skb; + + pr_debug("%s", __func__); + /* if the previous skb wasn't written completely + */ + if (st_gdata->tx_skb != NULL) { + returning_skb = st_gdata->tx_skb; + st_gdata->tx_skb = NULL; + return returning_skb; + } + + /* de-Q from the txQ always if previous write is complete */ + return skb_dequeue(&st_gdata->txq); +} + +/* internal Q-ing function + * will either Q the skb to txq or the tx_waitq + * depending on the ST LL state + * + * lock the whole func - since ll_getstate and Q-ing should happen + * in one-shot + */ +void st_int_enqueue(struct sk_buff *skb) +{ + unsigned long flags = 0; + + pr_debug("%s", __func__); + /* this function can be invoked in more then one context. + * so have a lock */ + spin_lock_irqsave(&st_gdata->lock, flags); + + switch (st_ll_getstate()) { + case ST_LL_AWAKE: + pr_debug("ST LL is AWAKE, sending normally"); + skb_queue_tail(&st_gdata->txq, skb); + break; + case ST_LL_ASLEEP_TO_AWAKE: + skb_queue_tail(&st_gdata->tx_waitq, skb); + break; + case ST_LL_AWAKE_TO_ASLEEP: /* host cannot be in this state */ + pr_err("ST LL is illegal state(%ld)," + "purging received skb.", st_ll_getstate()); + kfree_skb(skb); + break; + + case ST_LL_ASLEEP: + /* call a function of ST LL to put data + * in tx_waitQ and wake_ind in txQ + */ + skb_queue_tail(&st_gdata->tx_waitq, skb); + st_ll_wakeup(); + break; + default: + pr_err("ST LL is illegal state(%ld)," + "purging received skb.", st_ll_getstate()); + kfree_skb(skb); + break; + } + spin_unlock_irqrestore(&st_gdata->lock, flags); + pr_debug("done %s", __func__); + return; +} + +/* + * internal wakeup function + * called from either + * - TTY layer when write's finished + * - st_write (in context of the protocol stack) + */ +void st_tx_wakeup(struct st_data_s *st_data) +{ + struct sk_buff *skb; + unsigned long flags; /* for irq save flags */ + pr_debug("%s", __func__); + /* check for sending & set flag sending here */ + if (test_and_set_bit(ST_TX_SENDING, &st_data->tx_state)) { + pr_debug("ST already sending"); + /* keep sending */ + set_bit(ST_TX_WAKEUP, &st_data->tx_state); + return; + /* TX_WAKEUP will be checked in another + * context + */ + } + do { /* come back if st_tx_wakeup is set */ + /* woke-up to write */ + clear_bit(ST_TX_WAKEUP, &st_data->tx_state); + while ((skb = st_int_dequeue(st_data))) { + int len; + spin_lock_irqsave(&st_data->lock, flags); + /* enable wake-up from TTY */ + set_bit(TTY_DO_WRITE_WAKEUP, &st_data->tty->flags); + len = st_int_write(skb->data, skb->len); + skb_pull(skb, len); + /* if skb->len = len as expected, skb->len=0 */ + if (skb->len) { + /* would be the next skb to be sent */ + st_data->tx_skb = skb; + spin_unlock_irqrestore(&st_gdata->lock, flags); + break; + } + kfree_skb(skb); + spin_unlock_irqrestore(&st_gdata->lock, flags); + } + /* if wake-up is set in another context- restart sending */ + } while (test_bit(ST_TX_WAKEUP, &st_data->tx_state)); + + /* clear flag sending */ + clear_bit(ST_TX_SENDING, &st_data->tx_state); +} + +/********************************************************************/ +/* functions called from ST KIM +*/ +void kim_st_list_protocols(char *buf) +{ + unsigned long flags = 0; +#ifdef DEBUG + unsigned char i = ST_MAX; +#endif + spin_lock_irqsave(&st_gdata->lock, flags); +#ifdef DEBUG /* more detailed log */ + for (i = 0; i < ST_MAX; i++) { + if (i == 0) { + sprintf(buf, "%s is %s", protocol_strngs[i], + st_gdata->list[i] != + NULL ? "Registered" : "Unregistered"); + } else { + sprintf(buf, "%s\n%s is %s", buf, protocol_strngs[i], + st_gdata->list[i] != + NULL ? "Registered" : "Unregistered"); + } + } + sprintf(buf, "%s\n", buf); +#else /* limited info */ + sprintf(buf, "BT=%c\nFM=%c\nGPS=%c\n", + st_gdata->list[ST_BT] != NULL ? 'R' : 'U', + st_gdata->list[ST_FM] != NULL ? 'R' : 'U', + st_gdata->list[ST_GPS] != NULL ? 'R' : 'U'); +#endif + spin_unlock_irqrestore(&st_gdata->lock, flags); +} + +/********************************************************************/ +/* + * functions called from protocol stack drivers + * to be EXPORT-ed + */ +long st_register(struct st_proto_s *new_proto) +{ + long err = ST_SUCCESS; + unsigned long flags = 0; + + pr_debug("%s(%d) ", __func__, new_proto->type); + if (st_gdata == NULL || new_proto == NULL || new_proto->recv == NULL + || new_proto->reg_complete_cb == NULL) { + pr_err("gdata/new_proto/recv or reg_complete_cb not ready"); + return ST_ERR_FAILURE; + } + + if (new_proto->type < ST_BT || new_proto->type >= ST_MAX) { + pr_err("protocol %d not supported", new_proto->type); + return ST_ERR_NOPROTO; + } + + if (st_gdata->list[new_proto->type] != NULL) { + pr_err("protocol %d already registered", new_proto->type); + return ST_ERR_ALREADY; + } + + /* can be from process context only */ + spin_lock_irqsave(&st_gdata->lock, flags); + + if (test_bit(ST_REG_IN_PROGRESS, &st_gdata->st_state)) { + pr_debug(" ST_REG_IN_PROGRESS:%d ", new_proto->type); + /* fw download in progress */ + st_kim_chip_toggle(new_proto->type, KIM_GPIO_ACTIVE); + + st_gdata->list[new_proto->type] = new_proto; + new_proto->write = st_write; + + set_bit(ST_REG_PENDING, &st_gdata->st_state); + spin_unlock_irqrestore(&st_gdata->lock, flags); + return ST_ERR_PENDING; + } else if (is_protocol_list_empty() == ST_EMPTY) { + pr_debug(" protocol list empty :%d ", new_proto->type); + set_bit(ST_REG_IN_PROGRESS, &st_gdata->st_state); + st_recv = st_kim_recv; + + /* release lock previously held - re-locked below */ + spin_unlock_irqrestore(&st_gdata->lock, flags); + + /* enable the ST LL - to set default chip state */ + st_ll_enable(); + /* this may take a while to complete + * since it involves BT fw download + */ + err = st_kim_start(); + if (err != ST_SUCCESS) { + clear_bit(ST_REG_IN_PROGRESS, &st_gdata->st_state); + if ((is_protocol_list_empty() != ST_EMPTY) && + (test_bit(ST_REG_PENDING, &st_gdata->st_state))) { + pr_err(" KIM failure complete callback "); + st_reg_complete(ST_ERR_FAILURE); + } + + return ST_ERR_FAILURE; + } + + /* the protocol might require other gpios to be toggled + */ + st_kim_chip_toggle(new_proto->type, KIM_GPIO_ACTIVE); + + clear_bit(ST_REG_IN_PROGRESS, &st_gdata->st_state); + st_recv = st_int_recv; + + /* this is where all pending registration + * are signalled to be complete by calling callback functions + */ + if ((is_protocol_list_empty() != ST_EMPTY) && + (test_bit(ST_REG_PENDING, &st_gdata->st_state))) { + pr_debug(" call reg complete callback "); + st_reg_complete(ST_SUCCESS); + } + clear_bit(ST_REG_PENDING, &st_gdata->st_state); + + /* check for already registered once more, + * since the above check is old + */ + if (st_gdata->list[new_proto->type] != NULL) { + pr_err(" proto %d already registered ", + new_proto->type); + return ST_ERR_ALREADY; + } + + spin_lock_irqsave(&st_gdata->lock, flags); + st_gdata->list[new_proto->type] = new_proto; + new_proto->write = st_write; + spin_unlock_irqrestore(&st_gdata->lock, flags); + return err; + } + /* if fw is already downloaded & new stack registers protocol */ + else { + switch (new_proto->type) { + case ST_BT: + /* do nothing */ + break; + case ST_FM: + case ST_GPS: + st_kim_chip_toggle(new_proto->type, KIM_GPIO_ACTIVE); + break; + case ST_MAX: + default: + pr_err("%d protocol not supported", + new_proto->type); + err = ST_ERR_NOPROTO; + /* something wrong */ + break; + } + st_gdata->list[new_proto->type] = new_proto; + new_proto->write = st_write; + + /* lock already held before entering else */ + spin_unlock_irqrestore(&st_gdata->lock, flags); + return err; + } + pr_debug("done %s(%d) ", __func__, new_proto->type); +} +EXPORT_SYMBOL_GPL(st_register); + +/* to unregister a protocol - + * to be called from protocol stack driver + */ +long st_unregister(enum proto_type type) +{ + long err = ST_SUCCESS; + unsigned long flags = 0; + + pr_debug("%s: %d ", __func__, type); + + if (type < ST_BT || type >= ST_MAX) { + pr_err(" protocol %d not supported", type); + return ST_ERR_NOPROTO; + } + + spin_lock_irqsave(&st_gdata->lock, flags); + + if (st_gdata->list[type] == NULL) { + pr_err(" protocol %d not registered", type); + spin_unlock_irqrestore(&st_gdata->lock, flags); + return ST_ERR_NOPROTO; + } + + st_gdata->list[type] = NULL; + + /* kim ignores BT in the below function + * and handles the rest, BT is toggled + * only in kim_start and kim_stop + */ + st_kim_chip_toggle(type, KIM_GPIO_INACTIVE); + spin_unlock_irqrestore(&st_gdata->lock, flags); + + if ((is_protocol_list_empty() == ST_EMPTY) && + (!test_bit(ST_REG_PENDING, &st_gdata->st_state))) { + pr_debug(" all protocols unregistered "); + + /* stop traffic on tty */ + if (st_gdata->tty) { + tty_ldisc_flush(st_gdata->tty); + stop_tty(st_gdata->tty); + } + + /* all protocols now unregistered */ + st_kim_stop(); + /* disable ST LL */ + st_ll_disable(); + } + return err; +} + +/* + * called in protocol stack drivers + * via the write function pointer + */ +long st_write(struct sk_buff *skb) +{ +#ifdef DEBUG + enum proto_type protoid = ST_MAX; +#endif + long len; + struct st_data_s *st_data = st_gdata; + + if (unlikely(skb == NULL || st_gdata == NULL + || st_gdata->tty == NULL)) { + pr_err("data/tty unavailable to perform write"); + return ST_ERR_FAILURE; + } +#ifdef DEBUG /* open-up skb to read the 1st byte */ + switch (skb->data[0]) { + case HCI_COMMAND_PKT: + case HCI_ACLDATA_PKT: + case HCI_SCODATA_PKT: + protoid = ST_BT; + break; + case ST_FM_CH8_PKT: + protoid = ST_FM; + break; + case 0x09: + protoid = ST_GPS; + break; + } + if (unlikely(st_gdata->list[protoid] == NULL)) { + pr_err(" protocol %d not registered, and writing? ", + protoid); + return ST_ERR_FAILURE; + } +#endif + pr_debug("%d to be written", skb->len); + len = skb->len; + + /* st_ll to decide where to enqueue the skb */ + st_int_enqueue(skb); + /* wake up */ + st_tx_wakeup(st_data); + + /* return number of bytes written */ + return len; +} + +/* for protocols making use of shared transport */ +EXPORT_SYMBOL_GPL(st_unregister); + +/********************************************************************/ +/* + * functions called from TTY layer + */ +static int st_tty_open(struct tty_struct *tty) +{ + int err = ST_SUCCESS; + pr_debug("%s ", __func__); + + st_gdata->tty = tty; + + /* don't do an wakeup for now */ + clear_bit(TTY_DO_WRITE_WAKEUP, &tty->flags); + + /* mem already allocated + */ + tty->receive_room = 65536; + /* Flush any pending characters in the driver and discipline. */ + tty_ldisc_flush(tty); + tty_driver_flush_buffer(tty); + /* + * signal to UIM via KIM that - + * installation of N_TI_WL ldisc is complete + */ + st_kim_complete(); + pr_debug("done %s", __func__); + return err; +} + +static void st_tty_close(struct tty_struct *tty) +{ + unsigned char i = ST_MAX; + unsigned long flags = 0; + + pr_debug("%s ", __func__); + + /* TODO: + * if a protocol has been registered & line discipline + * un-installed for some reason - what should be done ? + */ + spin_lock_irqsave(&st_gdata->lock, flags); + for (i = ST_BT; i < ST_MAX; i++) { + if (st_gdata->list[i] != NULL) + pr_err("%d not un-registered", i); + st_gdata->list[i] = NULL; + } + spin_unlock_irqrestore(&st_gdata->lock, flags); + /* + * signal to UIM via KIM that - + * N_TI_WL ldisc is un-installed + */ + st_kim_complete(); + st_gdata->tty = NULL; + /* Flush any pending characters in the driver and discipline. */ + tty_ldisc_flush(tty); + tty_driver_flush_buffer(tty); + + spin_lock_irqsave(&st_gdata->lock, flags); + /* empty out txq and tx_waitq */ + skb_queue_purge(&st_gdata->txq); + skb_queue_purge(&st_gdata->tx_waitq); + /* reset the TTY Rx states of ST */ + st_gdata->rx_count = 0; + st_gdata->rx_state = ST_W4_PACKET_TYPE; + kfree_skb(st_gdata->rx_skb); + st_gdata->rx_skb = NULL; + spin_unlock_irqrestore(&st_gdata->lock, flags); + + pr_debug("%s: done ", __func__); +} + +static void st_tty_receive(struct tty_struct *tty, const unsigned char *data, + char *tty_flags, int count) +{ +#ifdef VERBOSE + long i; + printk(KERN_ERR "incoming data...\n"); + for (i = 0; i < count; i++) + printk(" %x", data[i]); + printk(KERN_ERR "\n.. data end\n"); +#endif + + /* + * if fw download is in progress then route incoming data + * to KIM for validation + */ + st_recv(data, count); + pr_debug("done %s", __func__); +} + +/* wake-up function called in from the TTY layer + * inside the internal wakeup function will be called + */ +static void st_tty_wakeup(struct tty_struct *tty) +{ + pr_debug("%s ", __func__); + /* don't do an wakeup for now */ + clear_bit(TTY_DO_WRITE_WAKEUP, &tty->flags); + + /* call our internal wakeup */ + st_tx_wakeup((void *)st_gdata); +} + +static void st_tty_flush_buffer(struct tty_struct *tty) +{ + pr_debug("%s ", __func__); + + kfree_skb(st_gdata->tx_skb); + st_gdata->tx_skb = NULL; + + tty->ops->flush_buffer(tty); + return; +} + +/********************************************************************/ +static int __init st_core_init(void) +{ + long err; + static struct tty_ldisc_ops *st_ldisc_ops; + + /* populate and register to TTY line discipline */ + st_ldisc_ops = kzalloc(sizeof(*st_ldisc_ops), GFP_KERNEL); + if (!st_ldisc_ops) { + pr_err("no mem to allocate"); + return -ENOMEM; + } + + st_ldisc_ops->magic = TTY_LDISC_MAGIC; + st_ldisc_ops->name = "n_st"; /*"n_hci"; */ + st_ldisc_ops->open = st_tty_open; + st_ldisc_ops->close = st_tty_close; + st_ldisc_ops->receive_buf = st_tty_receive; + st_ldisc_ops->write_wakeup = st_tty_wakeup; + st_ldisc_ops->flush_buffer = st_tty_flush_buffer; + st_ldisc_ops->owner = THIS_MODULE; + + err = tty_register_ldisc(N_TI_WL, st_ldisc_ops); + if (err) { + pr_err("error registering %d line discipline %ld", + N_TI_WL, err); + kfree(st_ldisc_ops); + return err; + } + pr_debug("registered n_shared line discipline"); + + st_gdata = kzalloc(sizeof(struct st_data_s), GFP_KERNEL); + if (!st_gdata) { + pr_err("memory allocation failed"); + err = tty_unregister_ldisc(N_TI_WL); + if (err) + pr_err("unable to un-register ldisc %ld", err); + kfree(st_ldisc_ops); + err = -ENOMEM; + return err; + } + + /* Initialize ST TxQ and Tx waitQ queue head. All BT/FM/GPS module skb's + * will be pushed in this queue for actual transmission. + */ + skb_queue_head_init(&st_gdata->txq); + skb_queue_head_init(&st_gdata->tx_waitq); + + /* Locking used in st_int_enqueue() to avoid multiple execution */ + spin_lock_init(&st_gdata->lock); + + /* ldisc_ops ref to be only used in __exit of module */ + st_gdata->ldisc_ops = st_ldisc_ops; + + err = st_kim_init(); + if (err) { + pr_err("error during kim initialization(%ld)", err); + kfree(st_gdata); + err = tty_unregister_ldisc(N_TI_WL); + if (err) + pr_err("unable to un-register ldisc"); + kfree(st_ldisc_ops); + return -1; + } + + err = st_ll_init(); + if (err) { + pr_err("error during st_ll initialization(%ld)", err); + err = st_kim_deinit(); + kfree(st_gdata); + err = tty_unregister_ldisc(N_TI_WL); + if (err) + pr_err("unable to un-register ldisc"); + kfree(st_ldisc_ops); + return -1; + } + return 0; +} + +static void __exit st_core_exit(void) +{ + long err; + /* internal module cleanup */ + err = st_ll_deinit(); + if (err) + pr_err("error during deinit of ST LL %ld", err); + err = st_kim_deinit(); + if (err) + pr_err("error during deinit of ST KIM %ld", err); + + if (st_gdata != NULL) { + /* Free ST Tx Qs and skbs */ + skb_queue_purge(&st_gdata->txq); + skb_queue_purge(&st_gdata->tx_waitq); + kfree_skb(st_gdata->rx_skb); + kfree_skb(st_gdata->tx_skb); + /* TTY ldisc cleanup */ + err = tty_unregister_ldisc(N_TI_WL); + if (err) + pr_err("unable to un-register ldisc %ld", err); + kfree(st_gdata->ldisc_ops); + /* free the global data pointer */ + kfree(st_gdata); + } +} + +module_init(st_core_init); +module_exit(st_core_exit); +MODULE_AUTHOR("Pavan Savoy <pavan_savoy(a)ti.com>"); +MODULE_DESCRIPTION("Shared Transport Driver for TI BT/FM/GPS combo chips "); +MODULE_LICENSE("GPL"); diff --git a/drivers/staging/ti-st/st_core.h b/drivers/staging/ti-st/st_core.h new file mode 100644 index 0000000..ff0d9d1 --- /dev/null +++ b/drivers/staging/ti-st/st_core.h @@ -0,0 +1,92 @@ +/* + * Shared Transport Core header file + * + * Copyright (C) 2009 Texas Instruments + * + * 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 + * + */ + +#ifndef ST_CORE_H +#define ST_CORE_H + +#include <linux/skbuff.h> +#include "st.h" + +/* states of protocol list */ +#define ST_NOTEMPTY 1 +#define ST_EMPTY 0 + +/* + * possible st_states + */ +#define ST_INITIALIZING 1 +#define ST_REG_IN_PROGRESS 2 +#define ST_REG_PENDING 3 +#define ST_WAITING_FOR_RESP 4 + +/* + * local data required for ST/KIM/ST-HCI-LL + */ +struct st_data_s { + unsigned long st_state; +/* + * an instance of tty_struct & ldisc ops to move around + */ + struct tty_struct *tty; + struct tty_ldisc_ops *ldisc_ops; +/* + * the tx skb - + * if the skb is already dequeued and the tty failed to write the same + * maintain the skb to write in the next transaction + */ + struct sk_buff *tx_skb; +#define ST_TX_SENDING 1 +#define ST_TX_WAKEUP 2 + unsigned long tx_state; +/* + * list of protocol registered + */ + struct st_proto_s *list[ST_MAX]; +/* + * lock + */ + unsigned long rx_state; + unsigned long rx_count; + struct sk_buff *rx_skb; + struct sk_buff_head txq, tx_waitq; + spinlock_t lock; /* ST LL state lock */ +}; + +/* point this to tty->driver->write or tty->ops->write + * depending upon the kernel version + */ +int st_int_write(const unsigned char *, int); +/* internal write function, passed onto protocol drivers + * via the write function ptr of protocol struct + */ +long st_write(struct sk_buff *); +/* function to be called from ST-LL + */ +void st_ll_send_frame(enum proto_type, struct sk_buff *); +/* internal wake up function */ +void st_tx_wakeup(struct st_data_s *st_data); + +#define GPS_STUB_TEST +#ifdef GPS_STUB_TEST +int gps_chrdrv_stub_write(const unsigned char*, int); +void gps_chrdrv_stub_init(void); +#endif + +#endif /*ST_CORE_H */ -- 1.5.4.3 > To unsubscribe from this list: send the line "unsubscribe > linux-kernel" in > the body of a message to majordomo(a)vger.kernel.org > More majordomo info at� http://vger.kernel.org/majordomo-info.html > Please read the FAQ at� http://www.tux.org/lkml/ > The INTERNET now has a personality. YOURS! See your Yahoo! Homepage. http://in.yahoo.com/ -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo(a)vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
From: Greg KH on 30 Mar 2010 18:50 On Wed, Mar 31, 2010 at 02:35:55AM +0530, Pavan Savoy wrote: > So, something like the below is ok, I have defined my own pr_fmt, > however default log level on my board is 7, and hence pr_info is a bit > more annoying than usual. No, a driver should use dev_dbg() and other dev_printk() calls, not pr_debug() or anything like that. Please don't roll your own formats, use the ones that are well defined and uniquely describe your driver and device in a format that the whole kernel uses. thanks, greg k-h -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo(a)vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
|
Next
|
Last
Pages: 1 2 3 4 5 Prev: [PATCH] rcu: more careful check for the last non-dyntick-idle CPU Next: [PATCH -v10 00/29] use lmb with x86 |