#include #include #include #include #include #include #include #include #include #include #include "phy-am335x-control.h" #include "phy-generic.h" struct am335x_phy { struct usb_phy_generic usb_phy_gen; struct phy_control *phy_ctrl; int id; enum usb_dr_mode dr_mode; }; static int am335x_init(struct usb_phy *phy) { struct am335x_phy *am_phy = dev_get_drvdata(phy->dev); phy_ctrl_power(am_phy->phy_ctrl, am_phy->id, am_phy->dr_mode, true); return 0; } static void am335x_shutdown(struct usb_phy *phy) { struct am335x_phy *am_phy = dev_get_drvdata(phy->dev); phy_ctrl_power(am_phy->phy_ctrl, am_phy->id, am_phy->dr_mode, false); } static int am335x_phy_probe(struct platform_device *pdev) { struct am335x_phy *am_phy; struct device *dev = &pdev->dev; int ret; am_phy = devm_kzalloc(dev, sizeof(*am_phy), GFP_KERNEL); if (!am_phy) return -ENOMEM; am_phy->phy_ctrl = am335x_get_phy_control(dev); if (!am_phy->phy_ctrl) return -EPROBE_DEFER; am_phy->id = of_alias_get_id(pdev->dev.of_node, "phy"); if (am_phy->id < 0) { dev_err(&pdev->dev, "Missing PHY id: %d\n", am_phy->id); return am_phy->id; } am_phy->dr_mode = of_usb_get_dr_mode_by_phy(pdev->dev.of_node, -1); ret = usb_phy_gen_create_phy(dev, &am_phy->usb_phy_gen, NULL); if (ret) return ret; ret = usb_add_phy_dev(&am_phy->usb_phy_gen.phy); if (ret) return ret; am_phy->usb_phy_gen.phy.init = am335x_init; am_phy->usb_phy_gen.phy.shutdown = am335x_shutdown; platform_set_drvdata(pdev, am_phy); device_init_wakeup(dev, true); /* * If we leave PHY wakeup enabled then AM33XX wakes up * immediately from DS0. To avoid this we mark dev->power.can_wakeup * to false. The same is checked in suspend routine to decide * on whether to enable PHY wakeup or not. * PHY wakeup works fine in standby mode, there by allowing us to * handle remote wakeup, wakeup on disconnect and connect. */ device_set_wakeup_enable(dev, false); phy_ctrl_power(am_phy->phy_ctrl, am_phy->id, am_phy->dr_mode, false); return 0; } static int am335x_phy_remove(struct platform_device *pdev) { struct am335x_phy *am_phy = platform_get_drvdata(pdev); usb_remove_phy(&am_phy->usb_phy_gen.phy); return 0; } #ifdef CONFIG_PM_SLEEP static int am335x_phy_suspend(struct device *dev) { struct platform_device *pdev = to_platform_device(dev); struct am335x_phy *am_phy = platform_get_drvdata(pdev); /* * Enable phy wakeup only if dev->power.can_wakeup is true. * Make sure to enable wakeup to support remote wakeup in * standby mode ( same is not supported in OFF(DS0) mode). * Enable it by doing * echo enabled > /sys/bus/platform/devices//power/wakeup */ if (device_may_wakeup(dev)) phy_ctrl_wkup(am_phy->phy_ctrl, am_phy->id, true); phy_ctrl_power(am_phy->phy_ctrl, am_phy->id, am_phy->dr_mode, false); return 0; } static int am335x_phy_resume(struct device *dev) { struct platform_device *pdev = to_platform_device(dev); struct am335x_phy *am_phy = platform_get_drvdata(pdev); phy_ctrl_power(am_phy->phy_ctrl, am_phy->id, am_phy->dr_mode, true); if (device_may_wakeup(dev)) phy_ctrl_wkup(am_phy->phy_ctrl, am_phy->id, false); return 0; } #endif static SIMPLE_DEV_PM_OPS(am335x_pm_ops, am335x_phy_suspend, am335x_phy_resume); static const struct of_device_id am335x_phy_ids[] = { { .compatible = "ti,am335x-usb-phy" }, { } }; MODULE_DEVICE_TABLE(of, am335x_phy_ids); static struct platform_driver am335x_phy_driver = { .probe = am335x_phy_probe, .remove = am335x_phy_remove, .driver = { .name = "am335x-phy-driver", .pm = &am335x_pm_ops, .of_match_table = am335x_phy_ids, }, }; module_platform_driver(am335x_phy_driver); MODULE_LICENSE("GPL v2"); rl'>mode:
authorIago Abal <mail@iagoabal.eu>2017-01-11 14:00:21 +0100
committerVinod Koul <vinod.koul@intel.com>2017-01-25 15:35:11 +0530
commit91539eb1fda2d530d3b268eef542c5414e54bf1a (patch)
tree960f5ca6342ad20837aff18aad6e8ecd7da32fd6 /include/net/rose.h
parent6610d0edf6dc7ee97e46ab3a538a565c79d26199 (diff)
dmaengine: pl330: fix double lock
The static bug finder EBA (http://www.iagoabal.eu/eba/) reported the following double-lock bug: Double lock: 1. spin_lock_irqsave(pch->lock, flags) at pl330_free_chan_resources:2236; 2. call to function `pl330_release_channel' immediately after; 3. call to function `dma_pl330_rqcb' in line 1753; 4. spin_lock_irqsave(pch->lock, flags) at dma_pl330_rqcb:1505. I have fixed it as suggested by Marek Szyprowski. First, I have replaced `pch->lock' with `pl330->lock' in functions `pl330_alloc_chan_resources' and `pl330_free_chan_resources'. This avoids the double-lock by acquiring a different lock than `dma_pl330_rqcb'. NOTE that, as a result, `pl330_free_chan_resources' executes `list_splice_tail_init' on `pch->work_list' under lock `pl330->lock', whereas in the rest of the code `pch->work_list' is protected by `pch->lock'. I don't know if this may cause race conditions. Similarly `pch->cyclic' is written by `pl330_alloc_chan_resources' under `pl330->lock' but read by `pl330_tx_submit' under `pch->lock'. Second, I have removed locking from `pl330_request_channel' and `pl330_release_channel' functions. Function `pl330_request_channel' is only called from `pl330_alloc_chan_resources', so the lock is already held. Function `pl330_release_channel' is called from `pl330_free_chan_resources', which already holds the lock, and from `pl330_del'. Function `pl330_del' is called in an error path of `pl330_probe' and at the end of `pl330_remove', but I assume that there cannot be concurrent accesses to the protected data at those points. Signed-off-by: Iago Abal <mail@iagoabal.eu> Reviewed-by: Marek Szyprowski <m.szyprowski@samsung.com> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Diffstat (limited to 'include/net/rose.h')