From 16c79a04e262e51c790af4b074963dd592c617f2 Mon Sep 17 00:00:00 2001 From: Steve Glendinning Date: Fri, 28 Sep 2012 00:57:52 +0000 Subject: [PATCH] smsc75xx: enable power saving mode during system suspend 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: Patch updated to change BUG_ON to WARN_ON_ONCE. http://code.google.com/p/chromium-os/issues/detail?id=31871 Signed-off-by: Steve Glendinning Signed-off-by: David S. Miller --- drivers/net/usb/smsc75xx.c | 57 ++++++++++++++++++++++++++++++++++++-- 1 file changed, 54 insertions(+), 3 deletions(-) diff --git a/drivers/net/usb/smsc75xx.c b/drivers/net/usb/smsc75xx.c index 1f45f7b2fe63..759e577008b0 100644 --- a/drivers/net/usb/smsc75xx.c +++ b/drivers/net/usb/smsc75xx.c @@ -1106,6 +1106,57 @@ 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; + + if (WARN_ON_ONCE(!dev)) + return -EINVAL; + + 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; + + if (WARN_ON_ONCE(!dev)) + return -EINVAL; + + 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 +1325,9 @@ 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, }; -- 2.20.1