Return-Path: Sender: "Gustavo F. Padovan" Date: Fri, 21 Jan 2011 15:57:18 -0200 From: "Gustavo F. Padovan" To: pavan_savoy@ti.com Cc: marcel@holtmann.org, linux-kernel@vger.kernel.org, linux-bluetooth@vger.kernel.org Subject: Re: [RFC 2/2] Bluetooth: btwilink driver Message-ID: <20110121175718.GD2400@joana> References: <1294138788-10307-1-git-send-email-pavan_savoy@ti.com> <1294138788-10307-2-git-send-email-pavan_savoy@ti.com> <1294138788-10307-3-git-send-email-pavan_savoy@ti.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <1294138788-10307-3-git-send-email-pavan_savoy@ti.com> List-ID: Hi Pavan, * pavan_savoy@ti.com [2011-01-04 04:59:48 -0600]: > From: Pavan Savoy > > -- 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 > --- > drivers/bluetooth/Kconfig | 10 + > drivers/bluetooth/Makefile | 1 + > drivers/bluetooth/btwilink.c | 397 ++++++++++++++++++++++++++++++++++++++++++ > 3 files changed, 408 insertions(+), 0 deletions(-) > create mode 100644 drivers/bluetooth/btwilink.c > > diff --git a/drivers/bluetooth/Kconfig b/drivers/bluetooth/Kconfig > index 02deef4..8e0de9a 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 "Texas Instruments WiLink7 driver" > + 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..0201aca > --- /dev/null > +++ b/drivers/bluetooth/btwilink.c > @@ -0,0 +1,397 @@ > +/* > + * 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 > + * Pavan Savoy > + * > + * 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 > +#include > +#include > + > +#include > + > +/* Bluetooth Driver Version */ > +#define VERSION "1.0" > + > +/* Number of seconds to wait for registration completion > + * when ST returns PENDING status. > + */ > +#define BT_REGISTER_TIMEOUT 6000 /* 6 sec */ > + > +/** > + * struct ti_st - driver operation structure > + * @hdev: hci device pointer which binds to bt driver > + * @reg_status: ST registration callback status > + * @st_write: write function provided by the ST driver > + * to be used by the driver during send_frame. > + * @wait_reg_completion - completion sync between ti_st_open > + * and ti_st_registration_completion_cb. > + */ > +struct ti_st { > + struct hci_dev *hdev; > + char reg_status; > + long (*st_write) (struct sk_buff *); > + struct completion wait_reg_completion; > +}; > + > +/* 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 = 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 = priv_data; > + > + /* Save registration status for use in ti_st_open() */ > + lhst->reg_status = data; > + /* complete the wait in ti_st_open() */ > + 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) > +{ > + struct ti_st *lhst = priv_data; > + int err; > + > + if (!skb) > + return -EFAULT; > + > + if (!lhst) { > + kfree_skb(skb); > + return -EFAULT; > + } > + > + skb->dev = (void *) lhst->hdev; > + > + /* Forward skb to HCI core layer */ > + err = hci_recv_frame(skb); > + if (err < 0) { > + BT_ERR("Unable to push skb to HCI core(%d)", err); > + 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[3] = { > + { > + .chnl_id = 0x02, /* ACL */ Please create macros for the chnl_id in the core driver. > + .recv = st_receive, > + .reg_complete_cb = st_registration_completion_cb, > + .hdr_len = 4, > + .offset_len_in_hdr = 2, > + .len_size = 2, > + .reserve = 8, > + }, > + { > + .chnl_id = 0x03, /* SCO */ > + .recv = st_receive, > + .reg_complete_cb = st_registration_completion_cb, > + .hdr_len = 3, > + .offset_len_in_hdr = 2, > + .len_size = 1, > + .reserve = 8, > + }, > + { > + .chnl_id = 0x04, /* HCI Events */ > + .recv = st_receive, > + .reg_complete_cb = st_registration_completion_cb, > + .hdr_len = 2, > + .offset_len_in_hdr = 1, > + .len_size = 1, > + .reserve = 8, > + }, > +}; > + > +/* 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, i; > + > + BT_DBG("%s %p", hdev->name, hdev); Blank line here. > + if (test_and_set_bit(HCI_RUNNING, &hdev->flags)) { > + BT_ERR("btwilink already opened"); No need for this BT_ERR. It already returns -EBUSY. > + return -EBUSY; > + } > + > + /* provide contexts for callbacks from ST */ > + hst = hdev->driver_data; > + > + for (i = 0; i < 3; i++) { > + ti_st_proto[i].priv_data = hst; > + ti_st_proto[i].max_frame_size = HCI_MAX_FRAME_SIZE; > + > + err = st_register(&ti_st_proto[i]); Let's change the order here. First if (!err) goto to "hst->st_write = ti_st_proto[i].write" if (err != -EINPROGRESS) { } then here code for err == -EINPROGRESS > + if (err == -EINPROGRESS) { > + /* ST is busy with either protocol > + * registration or firmware download. > + */ > + /* Prepare wait-for-completion handler data structures. > + */ > + 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->reg_status = -EINPROGRESS; > + > + BT_DBG("waiting for registration " > + "completion signal from ST"); > + timeleft = wait_for_completion_timeout > + (&hst->wait_reg_completion, > + msecs_to_jiffies(BT_REGISTER_TIMEOUT)); > + if (!timeleft) { > + clear_bit(HCI_RUNNING, &hdev->flags); > + BT_ERR("Timeout(%d sec),didn't get reg " > + "completion signal from ST", > + BT_REGISTER_TIMEOUT / 1000); > + return -ETIMEDOUT; > + } > + > + /* Is ST registration callback > + * called with ERROR status? */ > + if (hst->reg_status != 0) { > + clear_bit(HCI_RUNNING, &hdev->flags); > + BT_ERR("ST registration completed with invalid " > + "status %d", hst->reg_status); > + return -EAGAIN; > + } > + err = 0; remove this err = 0; and return 0 in the end of the function. > + } else if (err != 0) { > + clear_bit(HCI_RUNNING, &hdev->flags); > + BT_ERR("st_register failed %d", err); > + return err; > + } Blank line here. > + hst->st_write = ti_st_proto[i].write; > + if (!hst->st_write) { > + BT_ERR("undefined ST write function"); > + clear_bit(HCI_RUNNING, &hdev->flags); > + > + /* Undo registration with ST */ > + err = st_unregister(&ti_st_proto[i]); > + if (err) > + BT_ERR("st_unregister() failed with " > + "error %d", err); You are unregistering only one protocol here, if the fail happens in the third one you will leak two of them. > + > + hst->st_write = NULL; > + /* ti_st_proto.write is filled up by the > + * underlying shared transport driver > + * upon registration > + */ > + return err; > + } > + } > + > + return err; > +} > + > +/* Close device */ > +static int ti_st_close(struct hci_dev *hdev) > +{ > + int err, i; > + struct ti_st *hst = hdev->driver_data; > + > + if (!test_and_clear_bit(HCI_RUNNING, &hdev->flags)) > + return 0; > + > + for (i = 0; i < 3; i++) { > + /* continue to unregister from transport */ This comment is pointless. > + err = st_unregister(&ti_st_proto[i]); > + if (err) > + BT_ERR("st_unregister() failed with error %d", err); > + } > + > + hst->st_write = NULL; > + > + return err; err is will report the error if it happens in the first or second unregister. -- Gustavo F. Padovan http://profusion.mobi