Some of these chips have GNSS support. GNSS support
is available through channel 9 whilst FM is through channel 8.
Add support for it.
A driver providing a /dev/tigps device is found in some vendor-kernels. The
GNSS device provided by this patch seems to be compatible.
Signed-off-by: Andreas Kemnade <andreas@xxxxxxxxxxxx>
---
drivers/bluetooth/hci_ll.c | 154 ++++++++++++++++++++++++++++++++++++-
1 file changed, 153 insertions(+), 1 deletion(-)
diff --git a/drivers/bluetooth/hci_ll.c b/drivers/bluetooth/hci_ll.c
index 4a0b5c3160c2b..718dab0f529a7 100644
--- a/drivers/bluetooth/hci_ll.c
+++ b/drivers/bluetooth/hci_ll.c
@@ -39,6 +39,7 @@
#include <net/bluetooth/bluetooth.h>
#include <net/bluetooth/hci_core.h>
+#include <linux/gnss.h>
#include <linux/gpio/consumer.h>
#include <linux/nvmem-consumer.h>
@@ -68,6 +69,10 @@ struct ll_device {
struct gpio_desc *enable_gpio;
struct clk *ext_clk;
bdaddr_t bdaddr;
+
+ struct mutex gdev_mutex;
+ bool gdev_open;
+ struct gnss_device *gdev;
};
struct ll_struct {
@@ -78,6 +83,20 @@ struct ll_struct {
struct sk_buff_head tx_wait_q; /* HCILL wait queue */
};
+/* Channel-9 details for GPS */
+#define GPS_CH9_PKT_HDR_SIZE 4
+#define GPS_CH9_PKT_NUMBER 0x9
+#define GPS_CH9_OP_WRITE 0x1
+#define GPS_CH9_OP_READ 0x2
+#define GPS_CH9_OP_COMPLETED_EVT 0x3
+
+struct gnssdrv_event_hdr {
+ uint8_t opcode;
+ uint16_t plen;
+} __packed;
+
+
+static int gnss_recv_frame(struct hci_dev *hdev, struct sk_buff *skb);
/*
* Builds and sends an HCILL command packet.
* These are very simple packets with only 1 cmd byte
@@ -411,6 +430,13 @@ static int ll_recv_frame(struct hci_dev *hdev, struct sk_buff *skb)
.lsize = 0, \
.maxlen = 0
+#define LL_RECV_GNSS \
+ .type = GPS_CH9_PKT_NUMBER, \
+ .hlen = 3, \
+ .loff = 1, \
+ .lsize = 2 \
+
+
static const struct h4_recv_pkt ll_recv_pkts[] = {
{ H4_RECV_ACL, .recv = hci_recv_frame },
{ H4_RECV_SCO, .recv = hci_recv_frame },
@@ -419,6 +445,7 @@ static const struct h4_recv_pkt ll_recv_pkts[] = {
{ LL_RECV_SLEEP_ACK, .recv = ll_recv_frame },
{ LL_RECV_WAKE_IND, .recv = ll_recv_frame },
{ LL_RECV_WAKE_ACK, .recv = ll_recv_frame },
+ { LL_RECV_GNSS, .recv = gnss_recv_frame },
};
/* Recv data */
@@ -682,12 +709,124 @@ static int ll_setup(struct hci_uart *hu)
static const struct hci_uart_proto llp;
+static int gnss_lldev_open(struct gnss_device *gdev)
+{
+ struct ll_device *lldev = gnss_get_drvdata(gdev);
+
+ mutex_lock(&lldev->gdev_mutex);
+ lldev->gdev_open = true;
+ mutex_unlock(&lldev->gdev_mutex);
+
+ return 0;
+}
+
+static void gnss_lldev_close(struct gnss_device *gdev)
+{
+ struct ll_device *lldev = gnss_get_drvdata(gdev);
+
+ mutex_lock(&lldev->gdev_mutex);
+ lldev->gdev_open = false;
+ mutex_unlock(&lldev->gdev_mutex);
+}
+
+static int gnss_lldev_write_raw(struct gnss_device *gdev,
+ const unsigned char *buf, size_t count)
+{
+ struct ll_device *lldev = gnss_get_drvdata(gdev);
+ int err = 0;
+ struct sk_buff *skb = NULL;
+ struct gnssdrv_event_hdr gnssdrv_hdr = { GPS_CH9_OP_WRITE, 0x0000 };
+
+ /* allocate packet */
+ skb = bt_skb_alloc(sizeof(gnssdrv_hdr) + count, GFP_ATOMIC);
+ if (!skb) {
+ BT_ERR("cannot allocate memory for HCILL packet");
+ err = -ENOMEM;
+ goto out;
+ }
+
+ /* GPS channel */
+
+ gnssdrv_hdr.plen = count;
+ hci_skb_pkt_type(skb) = GPS_CH9_PKT_NUMBER;
+ skb_put_data(skb, &gnssdrv_hdr, sizeof(gnssdrv_hdr));
+ skb_put_data(skb, buf, count);
+
+ lldev->hu.hdev->send(lldev->hu.hdev, skb);
+
+ /* TODO: wait on completion? */
+ return count;
+out:
+ return err;
+}
+
+static const struct gnss_operations gnss_lldev_ops = {
+ .open = gnss_lldev_open,
+ .close = gnss_lldev_close,
+ .write_raw = gnss_lldev_write_raw,
+};
+
+static int gnss_recv_frame(struct hci_dev *hdev, struct sk_buff *skb)
+{
+ struct hci_uart *hu = hci_get_drvdata(hdev);
+ struct ll_device *lldev = container_of(hu, struct ll_device, hu);
+
+ if (!IS_ENABLED(CONFIG_GNSS))
+ return 0;
+
+ if (!lldev->gdev)
+ return 0;
+
+ if (hci_skb_pkt_type(skb) == GPS_CH9_PKT_NUMBER) {
+ struct gnssdrv_event_hdr *gnss_hdr =
+ (struct gnssdrv_event_hdr *)skb->data;
+ void *data = skb_pull(skb, sizeof(*gnss_hdr));
+ /*
+ * REVISIT: maybe do something with the completed
+ * event
+ */
+ if (gnss_hdr->opcode == GPS_CH9_OP_READ) {
+ mutex_lock(&lldev->gdev_mutex);
+ if (lldev->gdev_open)
+ gnss_insert_raw(lldev->gdev, data, skb->len);
+ mutex_unlock(&lldev->gdev_mutex);
+ }
+ }
+ kfree_skb(skb);
+
+ return 0;
+}
+
+static int ll_gnss_register(struct ll_device *lldev)
+{
+ struct gnss_device *gdev;
+ int ret;
+
+ gdev = gnss_allocate_device(&lldev->serdev->dev);
+ if (!gdev)
+ return -ENOMEM;
+
+ gdev->ops = &gnss_lldev_ops;
+ gdev->type = GNSS_TYPE_AI2;
+ gnss_set_drvdata(gdev, lldev);
+ mutex_init(&lldev->gdev_mutex);
+
+ ret = gnss_register_device(gdev);
+ if (ret == 0) {
+ lldev->gdev = gdev;
+ return 0;
+ }
+ gnss_put_device(gdev);
+ return ret;
+}
+
static int hci_ti_probe(struct serdev_device *serdev)
{
struct hci_uart *hu;
struct ll_device *lldev;
struct nvmem_cell *bdaddr_cell;
u32 max_speed = 3000000;
+ int ret;
lldev = devm_kzalloc(&serdev->dev, sizeof(struct ll_device), GFP_KERNEL);
if (!lldev)
@@ -756,14 +895,27 @@ static int hci_ti_probe(struct serdev_device *serdev)
kfree(bdaddr);
}
- return hci_uart_register_device(hu, &llp);
+ ret = hci_uart_register_device(hu, &llp);
+ if (ret)
+ return ret;
+
+ if (IS_ENABLED(CONFIG_GNSS) &&
+ strstr(of_node_full_name(serdev->dev.of_node), "gnss"))
+ ll_gnss_register(lldev);
+
+ return 0;
}
+
static void hci_ti_remove(struct serdev_device *serdev)
{
struct ll_device *lldev = serdev_device_get_drvdata(serdev);
hci_uart_unregister_device(&lldev->hu);
+ if (IS_ENABLED(CONFIG_GNSS) && lldev->gdev) {
+ gnss_deregister_device(lldev->gdev);
+ gnss_put_device(lldev->gdev);
+ }
}
static const struct of_device_id hci_ti_of_match[] = {
--
2.39.2
