@@ -23,12 +23,15 @@
#include <linux/serial_reg.h>
#include <linux/clk.h>
#include <linux/io.h>
+#include <linux/delay.h>
#include <plat/common.h>
#include <plat/board.h>
#include <plat/clock.h>
#include <plat/control.h>
+#include <asm/div64.h>
+
#include "prm.h"
#include "pm.h"
#include "prm-regbits-34xx.h"
@@ -36,13 +39,14 @@
#define UART_OMAP_NO_EMPTY_FIFO_READ_IP_REV 0x52
#define UART_OMAP_WER 0x17 /* Wake-up enable register */
-#define DEFAULT_TIMEOUT (5 * HZ)
+#define DEFAULT_TIMEOUT (5LL * NSEC_PER_SEC)
struct omap_uart_state {
int num;
int can_sleep;
- struct timer_list timer;
- u32 timeout;
+ ktime_t expire_time;
+ ktime_t garbage_time;
+ u64 timeout;
void __iomem *wk_st;
void __iomem *wk_en;
@@ -231,6 +235,9 @@ static inline void omap_uart_enable_clocks(struct omap_uart_state *uart)
clk_enable(uart->fck);
uart->clocked = 1;
omap_uart_restore_context(uart);
+
+ /* Set up garbage timer to ignore RX during first 1ms */
+ uart->garbage_time = ktime_add_ns(ktime_get(), NSEC_PER_MSEC);
}
#ifdef CONFIG_PM
@@ -302,9 +309,7 @@ static void omap_uart_block_sleep(struct omap_uart_state *uart)
omap_uart_smart_idle_enable(uart, 0);
uart->can_sleep = 0;
if (uart->timeout)
- mod_timer(&uart->timer, jiffies + uart->timeout);
- else
- del_timer(&uart->timer);
+ uart->expire_time = ktime_add_ns(ktime_get(), uart->timeout);
}
static void omap_uart_allow_sleep(struct omap_uart_state *uart)
@@ -317,25 +322,28 @@ static void omap_uart_allow_sleep(struct omap_uart_state *uart)
if (!uart->clocked)
return;
- omap_uart_smart_idle_enable(uart, 1);
+ if (serial_read_reg(uart->p, UART_LSR) & UART_LSR_TEMT)
+ omap_uart_smart_idle_enable(uart, 1);
uart->can_sleep = 1;
- del_timer(&uart->timer);
-}
-
-static void omap_uart_idle_timer(unsigned long data)
-{
- struct omap_uart_state *uart = (struct omap_uart_state *)data;
-
- omap_uart_allow_sleep(uart);
}
void omap_uart_prepare_idle(int num)
{
struct omap_uart_state *uart;
+ ktime_t t;
list_for_each_entry(uart, &uart_list, node) {
+ if (num == uart->num && !uart->can_sleep) {
+ t = ktime_get();
+ if (t.tv64 > uart->expire_time.tv64)
+ uart->can_sleep = 1;
+ }
if (num == uart->num && uart->can_sleep) {
- omap_uart_disable_clocks(uart);
+ if (serial_read_reg(uart->p, UART_LSR) &
+ UART_LSR_TEMT)
+ omap_uart_disable_clocks(uart);
+ else
+ omap_uart_smart_idle_enable(uart, 0);
return;
}
}
@@ -360,6 +368,7 @@ void omap_uart_resume_idle(int num)
/* Check for normal UART wakeup */
if (__raw_readl(uart->wk_st) & uart->wk_mask)
omap_uart_block_sleep(uart);
+
return;
}
}
@@ -407,10 +416,24 @@ int omap_uart_can_sleep(void)
static irqreturn_t omap_uart_interrupt(int irq, void *dev_id)
{
struct omap_uart_state *uart = dev_id;
+ u8 lsr;
+ int ret = IRQ_NONE;
- omap_uart_block_sleep(uart);
+ lsr = serial_read_reg(uart->p, UART_LSR);
+ /* Check for receive interrupt */
+ if (lsr & UART_LSR_DR) {
+ omap_uart_block_sleep(uart);
+ if (uart->garbage_time.tv64 &&
+ ktime_get().tv64 < uart->garbage_time.tv64) {
+ serial_read_reg(uart->p, UART_RX);
+ uart->garbage_time.tv64 = 0;
+ ret = IRQ_HANDLED;
+ }
+ }
+ if (lsr & UART_LSR_TEMT && uart->can_sleep)
+ omap_uart_smart_idle_enable(uart, 1);
- return IRQ_NONE;
+ return ret;
}
static void omap_uart_idle_init(struct omap_uart_state *uart)
@@ -420,9 +443,9 @@ static void omap_uart_idle_init(struct omap_uart_state *uart)
uart->can_sleep = 0;
uart->timeout = DEFAULT_TIMEOUT;
- setup_timer(&uart->timer, omap_uart_idle_timer,
- (unsigned long) uart);
- mod_timer(&uart->timer, jiffies + uart->timeout);
+
+ uart->expire_time = ktime_add_ns(ktime_get(), uart->timeout);
+
omap_uart_smart_idle_enable(uart, 0);
if (cpu_is_omap34xx()) {
@@ -505,8 +528,12 @@ static ssize_t sleep_timeout_show(struct device *dev,
struct platform_device, dev);
struct omap_uart_state *uart = container_of(pdev,
struct omap_uart_state, pdev);
+ u64 val;
+
+ val = uart->timeout;
- return sprintf(buf, "%u\n", uart->timeout / HZ);
+ do_div(val, NSEC_PER_SEC);
+ return sprintf(buf, "%llu\n", val);
}
static ssize_t sleep_timeout_store(struct device *dev,
@@ -524,10 +551,12 @@ static ssize_t sleep_timeout_store(struct device *dev,
return -EINVAL;
}
- uart->timeout = value * HZ;
- if (uart->timeout)
- mod_timer(&uart->timer, jiffies + uart->timeout);
- else
+ uart->timeout = (u64)value * NSEC_PER_SEC;
+ if (uart->timeout) {
+ uart->expire_time = ktime_get();
+ uart->expire_time =
+ ktime_add_ns(uart->expire_time, uart->timeout);
+ } else
/* A zero value means disable timeout feature */
omap_uart_block_sleep(uart);