From 454f83d5e60110a18f24ffc0d58d2252d09c9a92 Mon Sep 17 00:00:00 2001 From: Hans de Goede Date: Mon, 21 Nov 2016 08:59:23 -0600 Subject: [PATCH] musb: sunxi: Force session end on babble errors in host-mode The sunxi musb has a bug where sometimes it will generate a babble error on device disconnect instead of a disconnect irq. When this happens the musb-controller switches from host mode to device mode (it clears MUSB_DEVCTL_SESSION and sets MUSB_DEVCTL_BDEVICE) and gets stuck in this state. Clearing this requires reporting Vbus low for 200 or more ms, but on some devices Vbus is simply always high (host-only mode, no Vbus control). This commit adds a sunxi_musb_recover() callback which makes sunxi_musb_work call phy_set_mode with the current mode, which will force end the current session. This fixes the musb controller getting stuck in this state on systems without Vbus control; and also fixes the need to unplug the usb-b -> usb-a cable to get out of this state on systems with Vbus control. Signed-off-by: Hans de Goede Signed-off-by: Bin Liu Signed-off-by: Greg Kroah-Hartman --- drivers/usb/musb/sunxi.c | 15 +++++++++++++++ 1 file changed, 15 insertions(+) diff --git a/drivers/usb/musb/sunxi.c b/drivers/usb/musb/sunxi.c index 82eba92284c0..d0be0eadd0d9 100644 --- a/drivers/usb/musb/sunxi.c +++ b/drivers/usb/musb/sunxi.c @@ -380,6 +380,20 @@ static int sunxi_musb_set_mode(struct musb *musb, u8 mode) return 0; } +static int sunxi_musb_recover(struct musb *musb) +{ + struct sunxi_glue *glue = dev_get_drvdata(musb->controller->parent); + + /* + * Schedule a phy_set_mode with the current glue->phy_mode value, + * this will force end the current session. + */ + set_bit(SUNXI_MUSB_FL_PHY_MODE_PEND, &glue->flags); + schedule_work(&glue->work); + + return 0; +} + /* * sunxi musb register layout * 0x00 - 0x17 fifo regs, 1 long per fifo @@ -608,6 +622,7 @@ static const struct musb_platform_ops sunxi_musb_ops = { .dma_init = sunxi_musb_dma_controller_create, .dma_exit = sunxi_musb_dma_controller_destroy, .set_mode = sunxi_musb_set_mode, + .recover = sunxi_musb_recover, .set_vbus = sunxi_musb_set_vbus, .pre_root_reset_end = sunxi_musb_pre_root_reset_end, .post_root_reset_end = sunxi_musb_post_root_reset_end, -- 2.20.1