lkml.org 
[lkml]   [2010]   [Oct]   [18]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH] Bluetooth: btwilink driver
* Savoy, Pavan <pavan_savoy@ti.com> [2010-10-19 01:23:54 +0530]:

>
> > -----Original Message-----
> > From: Gustavo F. Padovan [mailto:pao@profusion.mobi] On Behalf Of Gustavo F.
> > Padovan
> > Sent: Monday, October 18, 2010 2:48 PM
> > To: Savoy, Pavan
> > Cc: marcel@holtmann.org; linux-bluetooth@vger.kernel.org; linux-
> > kernel@vger.kernel.org
> > Subject: Re: [PATCH] Bluetooth: btwilink driver
> >
> > Hi Pavan,
> >
> > * pavan_savoy@ti.com <pavan_savoy@ti.com> [2010-10-15 16:58:19 -0400]:
> >
> > > From: Pavan Savoy <pavan_savoy@ti.com>
> > >
> > > Gustavo, Marcel,
> > >
> > > Renaming the patch, since the driver is renamed to btwilink.
> > > Thanks for the comments,
> > > Please review and provide your comments on this version of patch,
> > >
> > > -- patch description --
> > >
> > > This is the bluetooth protocol driver for the TI WiLink7 chipsets.
> > > Texas Instrument's WiLink chipsets combine wireless technologies
> > > like BT, FM, GPS and WLAN onto a single chip.
> > >
> > > This Bluetooth driver works on top of the TI_ST shared transport
> > > line discipline driver which also allows other drivers like
> > > FM V4L2 and GPS character driver to make use of the same UART interface.
> > >
> > > Kconfig and Makefile modifications to enable the Bluetooth
> > > driver for Texas Instrument's WiLink 7 chipset.
> > >
> > > Signed-off-by: Pavan Savoy <pavan_savoy@ti.com>
> > > ---
> > > drivers/bluetooth/Kconfig | 10 +
> > > drivers/bluetooth/Makefile | 1 +
> > > drivers/bluetooth/btwilink.c | 424
> > ++++++++++++++++++++++++++++++++++++++++++
> > > 3 files changed, 435 insertions(+), 0 deletions(-)
> > > create mode 100644 drivers/bluetooth/btwilink.c
> > >
> > > diff --git a/drivers/bluetooth/Kconfig b/drivers/bluetooth/Kconfig
> > > index 02deef4..e0d67dd 100644
> > > --- a/drivers/bluetooth/Kconfig
> > > +++ b/drivers/bluetooth/Kconfig
> > > @@ -219,4 +219,14 @@ config BT_ATH3K
> > > Say Y here to compile support for "Atheros firmware download driver"
> > > into the kernel or say M to compile it as module (ath3k).
> > >
> > > +config BT_WILINK
> > > + tristate "BlueZ bluetooth driver for TI ST"
> > > + depends on TI_ST
> > > + help
> > > + This enables the Bluetooth driver for Texas Instrument's BT/FM/GPS
> > > + combo devices. This makes use of shared transport line discipline
> > > + core driver to communicate with the BT core of the combo chip.
> > > +
> > > + Say Y here to compile support for Texas Instrument's WiLink7 driver
> > > + into the kernel or say M to compile it as module.
> > > endmenu
> > > diff --git a/drivers/bluetooth/Makefile b/drivers/bluetooth/Makefile
> > > index 71bdf13..f4460f4 100644
> > > --- a/drivers/bluetooth/Makefile
> > > +++ b/drivers/bluetooth/Makefile
> > > @@ -18,6 +18,7 @@ obj-$(CONFIG_BT_HCIBTSDIO) += btsdio.o
> > > obj-$(CONFIG_BT_ATH3K) += ath3k.o
> > > obj-$(CONFIG_BT_MRVL) += btmrvl.o
> > > obj-$(CONFIG_BT_MRVL_SDIO) += btmrvl_sdio.o
> > > +obj-$(CONFIG_BT_WILINK) += btwilink.o
> > >
> > > btmrvl-y := btmrvl_main.o
> > > btmrvl-$(CONFIG_DEBUG_FS) += btmrvl_debugfs.o
> > > diff --git a/drivers/bluetooth/btwilink.c b/drivers/bluetooth/btwilink.c
> > > new file mode 100644
> > > index 0000000..f67791f
> > > --- /dev/null
> > > +++ b/drivers/bluetooth/btwilink.c
> > > @@ -0,0 +1,424 @@
> > > +/*
> > > + * Texas Instrument's Bluetooth Driver For Shared Transport.
> > > + *
> > > + * Bluetooth Driver acts as interface between HCI CORE and
> > > + * TI Shared Transport Layer.
> > > + *
> > > + * Copyright (C) 2009-2010 Texas Instruments
> > > + * Author: Raja Mani <raja_mani@ti.com>
> > > + * 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
> > > + *
> > > + */
> > > +
> > > +#include <linux/platform_device.h>
> > > +#include <net/bluetooth/bluetooth.h>
> > > +#include <net/bluetooth/hci_core.h>
> > > +
> > > +#include <linux/ti_wilink_st.h>
> > > +
> > > +/* Bluetooth Driver Version */
> > > +#define VERSION "1.0"
> > > +
> > > +/* Defines number of seconds to wait for reg completion
> > > + * callback getting called from ST (in case,registration
> > > + * with ST returns PENDING status)
> > > + */
> > > +#define BT_REGISTER_TIMEOUT 6000 /* 6 sec */
> > > +
> > > +/**
> > > + * struct ti_st - BT driver operation structure
> > > + * @hdev: hci device pointer which binds to bt driver
> > > + * @flags: used locally,to maintain various BT driver status
> > > + * @streg_cbdata: to hold ST registration callback status
> > > + * @st_write: write function pointer of ST driver
> > > + * @wait_reg_completion - completion sync between ti_st_open
> > > + * and ti_st_registration_completion_cb.
> > > + */
> > > +struct ti_st {
> > > + struct hci_dev *hdev;
> > > + char streg_cbdata;
> > > + long (*st_write) (struct sk_buff *);
> > > + struct completion wait_reg_completion;
> > > +};
> > > +
> > > +static int reset;
> > > +
> > > +/* Increments HCI counters based on pocket ID (cmd,acl,sco) */
> > > +static inline void ti_st_tx_complete(struct ti_st *hst, int pkt_type)
> > > +{
> > > + struct hci_dev *hdev;
> > > + hdev = hst->hdev;
> > > +
> > > + /* Update HCI stat counters */
> > > + switch (pkt_type) {
> > > + case HCI_COMMAND_PKT:
> > > + hdev->stat.cmd_tx++;
> > > + break;
> > > +
> > > + case HCI_ACLDATA_PKT:
> > > + hdev->stat.acl_tx++;
> > > + break;
> > > +
> > > + case HCI_SCODATA_PKT:
> > > + hdev->stat.sco_tx++;
> > > + break;
> > > + }
> > > +}
> > > +
> > > +/* ------- Interfaces to Shared Transport ------ */
> > > +
> > > +/* Called by ST layer to indicate protocol registration completion
> > > + * status.ti_st_open() function will wait for signal from this
> > > + * API when st_register() function returns ST_PENDING.
> > > + */
> > > +static void st_registration_completion_cb(void *priv_data, char data)
> > > +{
> > > + struct ti_st *lhst = (struct ti_st *)priv_data;
> >
> > Blank line here.
> >
> > > + /* ti_st_open() function needs value of 'data' to know
> > > + * the registration status(success/fail),So have a back
> > > + * up of it.
> > > + */
> > > + lhst->streg_cbdata = data;
> > > +
> > > + /* Got a feedback from ST for BT driver registration
> > > + * request.Wackup ti_st_open() function to continue
> > > + * it's open operation.
> > > + */
> > > + complete(&lhst->wait_reg_completion);
> > > +}
> > > +
> > > +/* Called by Shared Transport layer when receive data is
> > > + * available */
> > > +static long st_receive(void *priv_data, struct sk_buff *skb)
> > > +{
> > > + int err;
> > > + struct ti_st *lhst = (struct ti_st *)priv_data;
> > > +
> > > + if (!skb)
> > > + return -EFAULT;
> > > +
> > > + if (!lhst) {
> > > + kfree_skb(skb);
> > > + return -EFAULT;
> > > + }
> > > +
> > > + skb->dev = (struct net_device *)lhst->hdev;
> > > +
> > > + /* Forward skb to HCI CORE layer */
> > > + err = hci_recv_frame(skb);
> > > + if (err) {
> > > + kfree_skb(skb);
> > > + BT_ERR("Unable to push skb to HCI CORE(%d)", err);
> >
> > s/CORE/core/
> >
> > > + return err;
> > > + }
> > > +
> > > + lhst->hdev->stat.byte_rx += skb->len;
> > > + return 0;
> > > +}
> > > +
> > > +/* ------- Interfaces to HCI layer ------ */
> > > +/* protocol structure registered with shared transport */
> > > +static struct st_proto_s ti_st_proto = {
> > > + .type = ST_BT,
> > > + .recv = st_receive,
> > > + .reg_complete_cb = st_registration_completion_cb,
> > > + .priv_data = NULL,
> > > +};
> > > +
> > > +/* Called from HCI core to initialize the device */
> > > +static int ti_st_open(struct hci_dev *hdev)
> > > +{
> > > + unsigned long timeleft;
> > > + struct ti_st *hst;
> > > + int err;
> > > +
> > > + BT_DBG("%s %p", hdev->name, hdev);
> > > +
> > > + /* provide contexts for callbacks from ST */
> > > + hst = hdev->driver_data;
> > > + ti_st_proto.priv_data = hst;
> > > +
> > > + err = st_register(&ti_st_proto);
> > > + if (err == -EINPROGRESS) {
> > > + /* Prepare wait-for-completion handler data structures.
> > > + * Needed to syncronize this and st_registration_completion_cb()
> > > + * functions.
> > > + */
> > > + init_completion(&hst->wait_reg_completion);
> > > +
> > > + /* Reset ST registration callback status flag , this value
> > > + * will be updated in ti_st_registration_completion_cb()
> > > + * function whenever it called from ST driver.
> > > + */
> > > + hst->streg_cbdata = -EINPROGRESS;
> > > +
> > > + /* ST is busy with other protocol registration(may be busy with
> > > + * firmware download).So,Wait till the registration callback
> > > + * (passed as a argument to st_register() function) getting
> > > + * called from ST.
> > > + */
> > > + BT_DBG(" waiting for reg completion signal from ST");
> > > +
> > > + timeleft = wait_for_completion_timeout
> > > + (&hst->wait_reg_completion,
> > > + msecs_to_jiffies(BT_REGISTER_TIMEOUT));
> > > + if (!timeleft) {
> > > + BT_ERR("Timeout(%d sec),didn't get reg"
> > > + "completion signal from ST",
> > > + BT_REGISTER_TIMEOUT / 1000);
> >
> > How does this get printed. "...regcompletion..." ?
> >
> > > + return -ETIMEDOUT;
> > > + }
> > > +
> > > + /* Is ST registration callback called with ERROR value? */
> > > + if (hst->streg_cbdata != 0) {
> > > + BT_ERR("ST reg completion CB called with invalid"
> > > + "status %d", hst->streg_cbdata);
> > > + return -EAGAIN;
> > > + }
> > > + err = 0;
> > > + } else if (err == -EPERM) {
> > > + BT_ERR("st_register failed %d", err);
> > > + return -EAGAIN;
> >
> > Why? if -EPERM return -EAGAIN?
> >
> > > + }
> > > +
> > > + /* Do we have proper ST write function? */
> > > + if (ti_st_proto.write != NULL) {
> > > + /* We need this pointer for sending any Bluetooth pkts */
> > > + hst->st_write = ti_st_proto.write;
> >
> > I asked in the other e-mail: Who sets ti_st_proto.write()? I didn't get
> > this.
>
> The write function is set by the TI-ST driver.
> This was in order to avoid another EXPORT_SYMBOL(st_write) or so.
> So, as soon as some protocol driver registers to shared transport driver, the
> registration function inside the driver will set it's write function to this
> function pointer.

The usual approach is to export the symbol and use it inside your
driver. That is what most of our drivers do (if not all of them).
So I recommend you to change that in your driver.

--
Gustavo F. Padovan
ProFUSION embedded systems - http://profusion.mobi


\
 
 \ /
  Last update: 2010-10-18 22:13    [W:0.041 / U:0.200 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site