drivers: serial: amba-pl011: Introduce runtime pm

ST-Ericsson Linux next: -
ST-Ericsson ID: 373766
ST-Ericsson FOSS-OUT ID: Trivial

Change-Id: Ie2a7719ca602abf3fbb3e4cef05adc4f7ab07035
Signed-off-by: Jonas Aaberg <jonas.aberg@stericsson.com>
Reviewed-on: http://gerrit.lud.stericsson.com/gerrit/37021
Reviewed-by: QABUILD
Reviewed-by: Ulf HANSSON <ulf.hansson@stericsson.com>

1 files changed, 23 insertions, 8 deletions

diff --git a/drivers/tty/serial/amba-pl011.c b/drivers/tty/serial/amba-pl011.c
index 98da861fc8a..07d7081344e 100644
--- a/drivers/tty/serial/amba-pl011.c
+++ b/drivers/tty/serial/amba-pl011.c
@@ -53,6 +53,7 @@
 #include <linux/scatterlist.h>
 #include <linux/delay.h>
 #include <linux/types.h>
+#include <linux/pm_runtime.h>
 
 #include <asm/io.h>
 #include <asm/sizes.h>
@@ -1231,6 +1232,7 @@ static void pl011_clock_off(struct work_struct *work)
 	struct circ_buf *xmit = &port->state->xmit;
 	unsigned long flags;
 	bool disable_regulator = false;
+	bool runtime_put = false;
 	unsigned int busy, interrupt_status;
 
 	spin_lock_irqsave(&port->lock, flags);
@@ -1244,6 +1246,7 @@ static void pl011_clock_off(struct work_struct *work)
 					pl011_backup(uap, true);
 					disable_regulator = true;
 				}
+			runtime_put = true;
 			uap->clk_state = PL011_CLK_OFF;
 			clk_disable(uap->clk);
 		} else
@@ -1255,6 +1258,8 @@ static void pl011_clock_off(struct work_struct *work)
 
 	if (disable_regulator)
 		regulator_disable(uap->regulator);
+	if (runtime_put)
+		pm_runtime_put_sync(uap->port.dev);
 }
 
 /* Request to turn off uart clock once pending TX is flushed */
@@ -1285,6 +1290,7 @@ static void pl011_clock_on(struct uart_port *port)
 
 	switch (uap->clk_state) {
 	case PL011_CLK_OFF:
+		pm_runtime_get_sync(uap->port.dev);
 		clk_enable(uap->clk);
 		if (!uart_console(&uap->port) && uap->regulator) {
 			spin_unlock_irqrestore(&port->lock, flags);
@@ -1319,13 +1325,16 @@ static int pl011_power_startup(struct uart_amba_port *uap)
 	int retval = 0;
 
 	if (uap->clk_state == PL011_PORT_OFF) {
+		pm_runtime_get_sync(uap->port.dev);
 		if (!uart_console(&uap->port) && uap->regulator)
 			regulator_enable(uap->regulator);
 		retval = clk_enable(uap->clk);
-		if (!retval)
+		if (!retval) {
 			uap->clk_state = PL011_CLK_ON;
-		else
+		} else {
 			uap->clk_state = PL011_PORT_OFF;
+			pm_runtime_put_sync(uap->port.dev);
+		}
 	}
 
 	return retval;
@@ -1334,6 +1343,7 @@ static int pl011_power_startup(struct uart_amba_port *uap)
 static void pl011_power_shutdown(struct uart_amba_port *uap)
 {
 	bool disable_regulator = false;
+	bool runtime_put = false;
 
 	cancel_delayed_work_sync(&uap->clk_off_work);
 
@@ -1341,6 +1351,7 @@ static void pl011_power_shutdown(struct uart_amba_port *uap)
 	if (uap->clk_state == PL011_CLK_ON || 
 		uap->clk_state ==  PL011_CLK_REQUEST_OFF) {
 		clk_disable(uap->clk);
+		runtime_put = true;
 		if (!uart_console(&uap->port) && uap->regulator)
 			disable_regulator = true;
 	}
@@ -1349,6 +1360,8 @@ static void pl011_power_shutdown(struct uart_amba_port *uap)
 	
 	if (disable_regulator)
 		regulator_disable(uap->regulator);
+	if (runtime_put)
+		pm_runtime_put_sync(uap->port.dev);
 }
 
 static void
@@ -1378,12 +1391,14 @@ static inline void pl011_clock_check(struct uart_amba_port *uap)
 
 static inline int pl011_power_startup(struct uart_amba_port *uap)
 {
+	pm_runtime_get_sync(uap->port.dev);
 	return clk_enable(uap->clk);
 }
 
 static inline void pl011_power_shutdown(struct uart_amba_port *uap)
 {
 	clk_disable(uap->clk);
+	pm_runtime_put_sync(uap->port.dev);
 }
 
 static inline void
@@ -2288,6 +2303,10 @@ static int pl011_probe(struct amba_device *dev, const struct amba_id *id)
 	pl011_clock_control_init(uap);
 
 	ret = uart_add_one_port(&amba_reg, &uap->port);
+
+	if (!ret)
+		pm_runtime_put(&dev->dev);
+
 	if (ret) {
 		amba_set_drvdata(dev, NULL);
 		amba_ports[i] = NULL;
@@ -2301,12 +2320,6 @@ static int pl011_probe(struct amba_device *dev, const struct amba_id *id)
 		kfree(uap);
 	}
  out:
-	/*
-	 * Disable the silicon block pclk and any voltage domain and just
-	 * power it up and clock it when it's needed
-	 */
-	amba_pclk_disable(dev);
-	amba_vcore_disable(dev);
 
 	return ret;
 }
@@ -2318,6 +2331,8 @@ static int pl011_remove(struct amba_device *dev)
 
 	amba_set_drvdata(dev, NULL);
 
+	pm_runtime_get_sync(uap->port.dev);
+
 	uart_remove_one_port(&amba_reg, &uap->port);
 
 	for (i = 0; i < ARRAY_SIZE(amba_ports); i++)