#define IPC_WRITE_BUFFER 0x80
#define IPC_READ_BUFFER 0x90
+/* Timeout in jiffies */
+#define IPC_TIMEOUT (3 * HZ)
+
static DEFINE_MUTEX(ipclock); /* lock used to prevent multiple call to SCU */
/*
/* Wait till scu status is busy */
static inline int busy_loop(struct intel_scu_ipc_dev *scu)
{
- u32 status = ipc_read_status(scu);
- u32 loop_count = 100000;
+ unsigned long end = jiffies + msecs_to_jiffies(IPC_TIMEOUT);
- /* break if scu doesn't reset busy bit after huge retry */
- while ((status & IPC_STATUS_BUSY) && --loop_count) {
- udelay(1); /* scu processing time is in few u secods */
- status = ipc_read_status(scu);
- }
+ do {
+ u32 status;
- if (status & IPC_STATUS_BUSY) {
- dev_err(scu->dev, "IPC timed out");
- return -ETIMEDOUT;
- }
+ status = ipc_read_status(scu);
+ if (!(status & IPC_STATUS_BUSY))
+ return (status & IPC_STATUS_ERR) ? -EIO : 0;
- if (status & IPC_STATUS_ERR)
- return -EIO;
+ usleep_range(50, 100);
+ } while (time_before(jiffies, end));
- return 0;
+ dev_err(scu->dev, "IPC timed out");
+ return -ETIMEDOUT;
}
/* Wait till ipc ioc interrupt is received or timeout in 3 HZ */
{
int status;
- if (!wait_for_completion_timeout(&scu->cmd_complete, 3 * HZ)) {
+ if (!wait_for_completion_timeout(&scu->cmd_complete, IPC_TIMEOUT)) {
dev_err(scu->dev, "IPC timed out\n");
return -ETIMEDOUT;
}