bluetooth: Add wake locks for CG2900

This patch corrects some bad behavior for the CG2900 driver
when system suspends.
Wake locks are added to stop Android from suspending when chip
should be contacted.

Signed-off-by: Par-Gunnar Hjalmdahl <par-gunnar.p.hjalmdahl@stericsson.com>

1 files changed, 30 insertions, 0 deletions

diff --git a/drivers/staging/cg2900/bluetooth/cg2900_uart.c b/drivers/staging/cg2900/bluetooth/cg2900_uart.c
index 4417525306a..c0c8d8e30bd 100644
--- a/drivers/staging/cg2900/bluetooth/cg2900_uart.c
+++ b/drivers/staging/cg2900/bluetooth/cg2900_uart.c
@@ -31,6 +31,7 @@
 #include <linux/tty.h>
 #include <linux/tty_ldisc.h>
 #include <linux/types.h>
+#include <linux/wakelock.h>
 #include <linux/workqueue.h>
 #include <net/bluetooth/bluetooth.h>
 #include <net/bluetooth/hci.h>
@@ -285,6 +286,8 @@ struct uart_delayed_work_struct {
  * @chip_dev:		Chip device for current UART transport.
  * @cts_irq:		CTS interrupt for this UART.
  * @cts_gpio:		CTS GPIO for this UART.
+ * @wake_lock:		Wake lock for keeping user space awake (for Android).
+ * @suspend_blocked:	True if suspend operation is blocked in the framework.
  */
 struct uart_info {
 	enum uart_rx_state		rx_state;
@@ -312,6 +315,8 @@ struct uart_info {
 	struct cg2900_chip_dev		chip_dev;
 	int				cts_irq;
 	int				cts_gpio;
+	struct wake_lock		wake_lock;
+	bool				suspend_blocked;
 };
 
 /* Module parameters */
@@ -432,6 +437,10 @@ static irqreturn_t cts_interrupt(int irq, void *dev_id)
 	disable_irq_wake(irq);
 #endif
 	disable_irq_nosync(irq);
+	if (!uart_info->suspend_blocked) {
+		wake_lock(&uart_info->wake_lock);
+		uart_info->suspend_blocked = true;
+	}
 
 	/* Create work and leave IRQ context. */
 	(void)create_work_item(uart_info, handle_cts_irq);
@@ -586,6 +595,11 @@ static void wake_up_chip(struct uart_info *uart_info)
 	if (CHIP_POWERED_DOWN == uart_info->sleep_state)
 		goto finished;
 
+	if (!uart_info->suspend_blocked) {
+		wake_lock(&uart_info->wake_lock);
+		uart_info->suspend_blocked = true;
+	}
+
 	/*
 	 * This function indicates data is transmitted.
 	 * Therefore see to that the chip is awake.
@@ -698,6 +712,10 @@ static void set_chip_sleep_mode(struct work_struct *work)
 
 		dev_dbg(MAIN_DEV, "New sleep_state: CHIP_ASLEEP\n");
 		uart_info->sleep_state = CHIP_ASLEEP;
+		if (uart_info->suspend_blocked) {
+			wake_unlock(&uart_info->wake_lock);
+			uart_info->suspend_blocked = false;
+		}
 		break;
 	case CHIP_AWAKE:
 		chars_in_buffer = hci_uart_chars_in_buffer(uart_info->hu);
@@ -1327,6 +1345,10 @@ static void uart_set_chip_power(struct cg2900_chip_dev *dev, bool chip_on)
 	}
 
 	if (chip_on) {
+		if (!uart_info->suspend_blocked) {
+			wake_lock(&uart_info->wake_lock);
+			uart_info->suspend_blocked = true;
+		}
 		if (uart_info->sleep_state != CHIP_POWERED_DOWN) {
 			dev_err(MAIN_DEV, "Chip is already powered up (%d)\n",
 				uart_info->sleep_state);
@@ -1363,6 +1385,11 @@ static void uart_set_chip_power(struct cg2900_chip_dev *dev, bool chip_on)
 			break;
 		}
 
+		if (uart_info->suspend_blocked) {
+			wake_unlock(&uart_info->wake_lock);
+			uart_info->suspend_blocked = false;
+		}
+
 		if (pf_data->disable_chip) {
 			pf_data->disable_chip(dev);
 			dev_dbg(MAIN_DEV,
@@ -1914,6 +1941,8 @@ static int __devinit cg2900_uart_probe(struct platform_device *pdev)
 	uart_info->chip_dev.pdev = pdev;
 	uart_info->chip_dev.dev = &pdev->dev;
 	uart_info->chip_dev.t_data = uart_info;
+	wake_lock_init(&uart_info->wake_lock, WAKE_LOCK_SUSPEND, NAME);
+	uart_info->suspend_blocked = false;
 
 	resource = platform_get_resource_byname(pdev, IORESOURCE_IRQ,
 						"cts_irq");
@@ -2010,6 +2039,7 @@ static int __devexit cg2900_uart_remove(struct platform_device *pdev)
 	if (uart_info->hu)
 		hci_uart_unregister_proto(uart_info->hu->proto);
 
+	wake_lock_destroy(&uart_info->wake_lock);
 	destroy_workqueue(uart_info->wq);
 
 	dev_info(MAIN_DEV, "CG2900 UART removed\n");