[Bluetooth] Add generic driver for Bluetooth SDIO devices

This patch adds a generic driver for Bluetooth SDIO devices. It
supports Type-A and Type-B devices.

Signed-off-by: David Vrabel <david.vrabel@csr.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

1 files changed, 406 insertions, 0 deletions

diff --git a/drivers/bluetooth/btsdio.c b/drivers/bluetooth/btsdio.c
new file mode 100644
index 0000000..b786f61
--- /dev/null
+++ b/drivers/bluetooth/btsdio.c
@@ -0,0 +1,406 @@
+/*
+ *
+ *  Generic Bluetooth SDIO driver
+ *
+ *  Copyright (C) 2007  Cambridge Silicon Radio Ltd.
+ *  Copyright (C) 2007  Marcel Holtmann <marcel@holtmann.org>
+ *
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  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/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <linux/types.h>
+#include <linux/sched.h>
+#include <linux/errno.h>
+#include <linux/skbuff.h>
+
+#include <linux/mmc/sdio_ids.h>
+#include <linux/mmc/sdio_func.h>
+
+#include <net/bluetooth/bluetooth.h>
+#include <net/bluetooth/hci_core.h>
+
+#ifndef CONFIG_BT_HCIBTSDIO_DEBUG
+#undef  BT_DBG
+#define BT_DBG(D...)
+#endif
+
+#define VERSION "0.1"
+
+static const struct sdio_device_id btsdio_table[] = {
+	/* Generic Bluetooth Type-A SDIO device */
+	{ SDIO_DEVICE_CLASS(SDIO_CLASS_BT_A) },
+
+	/* Generic Bluetooth Type-B SDIO device */
+	{ SDIO_DEVICE_CLASS(SDIO_CLASS_BT_B) },
+
+	{ }	/* Terminating entry */
+};
+
+MODULE_DEVICE_TABLE(sdio, btsdio_table);
+
+struct btsdio_data {
+	struct hci_dev   *hdev;
+	struct sdio_func *func;
+
+	struct work_struct work;
+
+	struct sk_buff_head txq;
+};
+
+#define REG_RDAT     0x00	/* Receiver Data */
+#define REG_TDAT     0x00	/* Transmitter Data */
+#define REG_PC_RRT   0x10	/* Read Packet Control */
+#define REG_PC_WRT   0x11	/* Write Packet Control */
+#define REG_RTC_STAT 0x12	/* Retry Control Status */
+#define REG_RTC_SET  0x12	/* Retry Control Set */
+#define REG_INTRD    0x13	/* Interrupt Indication */
+#define REG_CL_INTRD 0x13	/* Interrupt Clear */
+#define REG_EN_INTRD 0x14	/* Interrupt Enable */
+#define REG_MD_STAT  0x20	/* Bluetooth Mode Status */
+
+static int btsdio_tx_packet(struct btsdio_data *data, struct sk_buff *skb)
+{
+	int err;
+
+	BT_DBG("%s", data->hdev->name);
+
+	/* Prepend Type-A header */
+	skb_push(skb, 4);
+	skb->data[0] = (skb->len & 0x0000ff);
+	skb->data[1] = (skb->len & 0x00ff00) >> 8;
+	skb->data[2] = (skb->len & 0xff0000) >> 16;
+	skb->data[3] = bt_cb(skb)->pkt_type;
+
+	err = sdio_writesb(data->func, REG_TDAT, skb->data, skb->len);
+	if (err < 0) {
+		sdio_writeb(data->func, 0x01, REG_PC_WRT, NULL);
+		return err;
+	}
+
+	data->hdev->stat.byte_tx += skb->len;
+
+	kfree_skb(skb);
+
+	return 0;
+}
+
+static void btsdio_work(struct work_struct *work)
+{
+	struct btsdio_data *data = container_of(work, struct btsdio_data, work);
+	struct sk_buff *skb;
+	int err;
+
+	BT_DBG("%s", data->hdev->name);
+
+	sdio_claim_host(data->func);
+
+	while ((skb = skb_dequeue(&data->txq))) {
+		err = btsdio_tx_packet(data, skb);
+		if (err < 0) {
+			data->hdev->stat.err_tx++;
+			skb_queue_head(&data->txq, skb);
+			break;
+		}
+	}
+
+	sdio_release_host(data->func);
+}
+
+static int btsdio_rx_packet(struct btsdio_data *data)
+{
+	u8 hdr[4] __attribute__ ((aligned(4)));
+	struct sk_buff *skb;
+	int err, len;
+
+	BT_DBG("%s", data->hdev->name);
+
+	err = sdio_readsb(data->func, hdr, REG_RDAT, 4);
+	if (err < 0)
+		return err;
+
+	len = hdr[0] | (hdr[1] << 8) | (hdr[2] << 16);
+	if (len < 4 || len > 65543)
+		return -EILSEQ;
+
+	skb = bt_skb_alloc(len - 4, GFP_KERNEL);
+	if (!skb) {
+		/* Out of memory. Prepare a read retry and just
+		 * return with the expectation that the next time
+		 * we're called we'll have more memory. */
+		return -ENOMEM;
+	}
+
+	skb_put(skb, len - 4);
+
+	err = sdio_readsb(data->func, skb->data, REG_RDAT, len - 4);
+	if (err < 0) {
+		kfree(skb);
+		return err;
+	}
+
+	data->hdev->stat.byte_rx += len;
+
+	skb->dev = (void *) data->hdev;
+	bt_cb(skb)->pkt_type = hdr[3];
+
+	err = hci_recv_frame(skb);
+	if (err < 0) {
+		kfree(skb);
+		return err;
+	}
+
+	sdio_writeb(data->func, 0x00, REG_PC_RRT, NULL);
+
+	return 0;
+}
+
+static void btsdio_interrupt(struct sdio_func *func)
+{
+	struct btsdio_data *data = sdio_get_drvdata(func);
+	int intrd;
+
+	BT_DBG("%s", data->hdev->name);
+
+	intrd = sdio_readb(func, REG_INTRD, NULL);
+	if (intrd & 0x01) {
+		sdio_writeb(func, 0x01, REG_CL_INTRD, NULL);
+
+		if (btsdio_rx_packet(data) < 0) {
+			data->hdev->stat.err_rx++;
+			sdio_writeb(data->func, 0x01, REG_PC_RRT, NULL);
+		}
+	}
+}
+
+static int btsdio_open(struct hci_dev *hdev)
+{
+	struct btsdio_data *data = hdev->driver_data;
+	int err;
+
+	BT_DBG("%s", hdev->name);
+
+	if (test_and_set_bit(HCI_RUNNING, &hdev->flags))
+		return 0;
+
+	sdio_claim_host(data->func);
+
+	err = sdio_enable_func(data->func);
+	if (err < 0) {
+		clear_bit(HCI_RUNNING, &hdev->flags);
+		goto release;
+	}
+
+	err = sdio_claim_irq(data->func, btsdio_interrupt);
+	if (err < 0) {
+		sdio_disable_func(data->func);
+		clear_bit(HCI_RUNNING, &hdev->flags);
+		goto release;
+	}
+
+	if (data->func->class == SDIO_CLASS_BT_B)
+		sdio_writeb(data->func, 0x00, REG_MD_STAT, NULL);
+
+	sdio_writeb(data->func, 0x01, REG_EN_INTRD, NULL);
+
+release:
+	sdio_release_host(data->func);
+
+	return err;
+}
+
+static int btsdio_close(struct hci_dev *hdev)
+{
+	struct btsdio_data *data = hdev->driver_data;
+
+	BT_DBG("%s", hdev->name);
+
+	if (!test_and_clear_bit(HCI_RUNNING, &hdev->flags))
+		return 0;
+
+	sdio_claim_host(data->func);
+
+	sdio_writeb(data->func, 0x00, REG_EN_INTRD, NULL);
+
+	sdio_release_irq(data->func);
+	sdio_disable_func(data->func);
+
+	sdio_release_host(data->func);
+
+	return 0;
+}
+
+static int btsdio_flush(struct hci_dev *hdev)
+{
+	struct btsdio_data *data = hdev->driver_data;
+
+	BT_DBG("%s", hdev->name);
+
+	skb_queue_purge(&data->txq);
+
+	return 0;
+}
+
+static int btsdio_send_frame(struct sk_buff *skb)
+{
+	struct hci_dev *hdev = (struct hci_dev *) skb->dev;
+	struct btsdio_data *data = hdev->driver_data;
+
+	BT_DBG("%s", hdev->name);
+
+	if (!test_bit(HCI_RUNNING, &hdev->flags))
+		return -EBUSY;
+
+	switch (bt_cb(skb)->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;
+
+	default:
+		return -EILSEQ;
+	}
+
+	skb_queue_tail(&data->txq, skb);
+
+	schedule_work(&data->work);
+
+	return 0;
+}
+
+static void btsdio_destruct(struct hci_dev *hdev)
+{
+	struct btsdio_data *data = hdev->driver_data;
+
+	BT_DBG("%s", hdev->name);
+
+	kfree(data);
+}
+
+static int btsdio_probe(struct sdio_func *func,
+				const struct sdio_device_id *id)
+{
+	struct btsdio_data *data;
+	struct hci_dev *hdev;
+	struct sdio_func_tuple *tuple = func->tuples;
+	int err;
+
+	BT_DBG("func %p id %p class 0x%04x", func, id, func->class);
+
+	while (tuple) {
+		BT_DBG("code 0x%x size %d", tuple->code, tuple->size);
+		tuple = tuple->next;
+	}
+
+	data = kzalloc(sizeof(*data), GFP_KERNEL);
+	if (!data)
+		return -ENOMEM;
+
+	data->func = func;
+
+	INIT_WORK(&data->work, btsdio_work);
+
+	skb_queue_head_init(&data->txq);
+
+	hdev = hci_alloc_dev();
+	if (!hdev) {
+		kfree(data);
+		return -ENOMEM;
+	}
+
+	hdev->type = HCI_SDIO;
+	hdev->driver_data = data;
+
+	data->hdev = hdev;
+
+	SET_HCIDEV_DEV(hdev, &func->dev);
+
+	hdev->open     = btsdio_open;
+	hdev->close    = btsdio_close;
+	hdev->flush    = btsdio_flush;
+	hdev->send     = btsdio_send_frame;
+	hdev->destruct = btsdio_destruct;
+
+	hdev->owner = THIS_MODULE;
+
+	err = hci_register_dev(hdev);
+	if (err < 0) {
+		hci_free_dev(hdev);
+		kfree(data);
+		return err;
+	}
+
+	sdio_set_drvdata(func, data);
+
+	return 0;
+}
+
+static void btsdio_remove(struct sdio_func *func)
+{
+	struct btsdio_data *data = sdio_get_drvdata(func);
+	struct hci_dev *hdev;
+
+	BT_DBG("func %p", func);
+
+	if (!data)
+		return;
+
+	hdev = data->hdev;
+
+	sdio_set_drvdata(func, NULL);
+
+	hci_unregister_dev(hdev);
+
+	hci_free_dev(hdev);
+}
+
+static struct sdio_driver btsdio_driver = {
+	.name		= "btsdio",
+	.probe		= btsdio_probe,
+	.remove		= btsdio_remove,
+	.id_table	= btsdio_table,
+};
+
+static int __init btsdio_init(void)
+{
+	BT_INFO("Generic Bluetooth SDIO driver ver %s", VERSION);
+
+	return sdio_register_driver(&btsdio_driver);
+}
+
+static void __exit btsdio_exit(void)
+{
+	sdio_unregister_driver(&btsdio_driver);
+}
+
+module_init(btsdio_init);
+module_exit(btsdio_exit);
+
+MODULE_AUTHOR("Marcel Holtmann <marcel@holtmann.org>");
+MODULE_DESCRIPTION("Generic Bluetooth SDIO driver ver " VERSION);
+MODULE_VERSION(VERSION);
+MODULE_LICENSE("GPL");