[PATCH 1/2] smsc75xx: add explicit test that device is READY

[PATCH 1/2] smsc75xx: add explicit test that device is READY

[Steve Glendinning]

This patch adds an explicit test that the READY bit is set on
the device when attempting to initialize it.

If this bit is clear then the device hasn't succesfully started
all its clocks, and this patch helps make the resulting logged
error more helpful.

Signed-off-by: Steve Glendinning <steve.glendinning@shawell.net>
---
 drivers/net/usb/smsc75xx.c |   23 +++++++++++++++++++++++
 1 file changed, 23 insertions(+)

diff --git a/drivers/net/usb/smsc75xx.c b/drivers/net/usb/smsc75xx.c
index 376143e..1f45f7b 100644
--- a/drivers/net/usb/smsc75xx.c
+++ b/drivers/net/usb/smsc75xx.c
@@ -756,6 +756,26 @@ static int smsc75xx_set_features(struct net_device *netdev,
 	return 0;
 }
 
+static int smsc75xx_wait_ready(struct usbnet *dev)
+{
+	int timeout = 0;
+
+	do {
+		u32 buf;
+		int ret = smsc75xx_read_reg(dev, PMT_CTL, &buf);
+		check_warn_return(ret, "Failed to read PMT_CTL: %d", ret);
+
+		if (buf & PMT_CTL_DEV_RDY)
+			return 0;
+
+		msleep(10);
+		timeout++;
+	} while (timeout < 100);
+
+	netdev_warn(dev->net, "timeout waiting for device ready");
+	return -EIO;
+}
+
 static int smsc75xx_reset(struct usbnet *dev)
 {
 	struct smsc75xx_priv *pdata = (struct smsc75xx_priv *)(dev->data[0]);
@@ -764,6 +784,9 @@ static int smsc75xx_reset(struct usbnet *dev)
 
 	netif_dbg(dev, ifup, dev->net, "entering smsc75xx_reset");
 
+	ret = smsc75xx_wait_ready(dev);
+	check_warn_return(ret, "device not ready in smsc75xx_reset");
+
 	ret = smsc75xx_read_reg(dev, HW_CFG, &buf);
 	check_warn_return(ret, "Failed to read HW_CFG: %d", ret);
 
-- 
1.7.9.5

[PATCH 2/2] smsc75xx: enable power saving mode during system suspend

[Steve Glendinning]

This patch instructs the device to enter its lowest power SUSPEND2
state during system suspend.

This patch also explicitly wakes the device after resume, which
should address reports of the device not automatically coming
back after system suspend:

http://code.google.com/p/chromium-os/issues/detail?id=31871

Signed-off-by: Steve Glendinning <steve.glendinning@shawell.net>
---
 drivers/net/usb/smsc75xx.c |   55 +++++++++++++++++++++++++++++++++++++++++---
 1 file changed, 52 insertions(+), 3 deletions(-)

diff --git a/drivers/net/usb/smsc75xx.c b/drivers/net/usb/smsc75xx.c
index 1f45f7b..83b9927 100644
--- a/drivers/net/usb/smsc75xx.c
+++ b/drivers/net/usb/smsc75xx.c
@@ -1106,6 +1106,55 @@ static void smsc75xx_unbind(struct usbnet *dev, struct usb_interface *intf)
 	}
 }
 
+static int smsc75xx_suspend(struct usb_interface *intf, pm_message_t message)
+{
+	struct usbnet *dev = usb_get_intfdata(intf);
+	int ret;
+	u32 val;
+
+	BUG_ON(!dev);
+
+	ret = usbnet_suspend(intf, message);
+	check_warn_return(ret, "usbnet_suspend error");
+
+	netdev_info(dev->net, "entering SUSPEND2 mode");
+
+	ret = smsc75xx_read_reg(dev, PMT_CTL, &val);
+	check_warn_return(ret, "Error reading PMT_CTL");
+
+	val &= ~(PMT_CTL_SUS_MODE | PMT_CTL_WUPS | PMT_CTL_PHY_RST);
+	val |= PMT_CTL_SUS_MODE_2;
+
+	ret = smsc75xx_write_reg(dev, PMT_CTL, val);
+	check_warn_return(ret, "Error writing PMT_CTL");
+
+	return 0;
+}
+
+static int smsc75xx_resume(struct usb_interface *intf)
+{
+	struct usbnet *dev = usb_get_intfdata(intf);
+	int ret;
+	u32 val;
+
+	BUG_ON(!dev);
+
+	netdev_info(dev->net, "resuming from SUSPEND2");
+
+	ret = smsc75xx_read_reg(dev, PMT_CTL, &val);
+	check_warn_return(ret, "Error reading PMT_CTL");
+
+	val |= PMT_CTL_PHY_PWRUP;
+
+	ret = smsc75xx_write_reg(dev, PMT_CTL, val);
+	check_warn_return(ret, "Error writing PMT_CTL");
+
+	ret = smsc75xx_wait_ready(dev);
+	check_warn_return(ret, "device not ready in smsc75xx_resume");
+
+	return usbnet_resume(intf);
+}
+
 static void smsc75xx_rx_csum_offload(struct usbnet *dev, struct sk_buff *skb,
 				     u32 rx_cmd_a, u32 rx_cmd_b)
 {
@@ -1274,9 +1323,9 @@ static struct usb_driver smsc75xx_driver = {
 	.name		= SMSC_CHIPNAME,
 	.id_table	= products,
 	.probe		= usbnet_probe,
-	.suspend	= usbnet_suspend,
-	.resume		= usbnet_resume,
-	.reset_resume	= usbnet_resume,
+	.suspend	= smsc75xx_suspend,
+	.resume		= smsc75xx_resume,
+	.reset_resume	= smsc75xx_resume,
 	.disconnect	= usbnet_disconnect,
 	.disable_hub_initiated_lpm = 1,
 };
-- 
1.7.9.5