From f042e9cbae607c323e3de86fc714b7306774a151 Mon Sep 17 00:00:00 2001 From: Sebastian Andrzej Siewior Date: Mon, 13 Oct 2014 11:04:21 +0200 Subject: [PATCH] usb: musb: musb_dsps: fix NULL pointer in suspend So testing managed to configure musb in DMA mode but not load the matching cppi41 driver for DMA. This results in |musb-hdrc musb-hdrc.0.auto: Failed to request rx1. |musb-hdrc musb-hdrc.0.auto: musb_init_controller failed with status -517 |platform musb-hdrc.0.auto: Driver musb-hdrc requests probe deferral which is "okay". Once the driver is loaded we re-try probing and everyone is happy. Until then if you try suspend say echo mem > /sys/power/state then you go boom |Unable to handle kernel NULL pointer dereference at virtual address 000003a4 |pgd = cf50c000 |[000003a4] *pgd=8f6a3831, *pte=00000000, *ppte=00000000 |Internal error: Oops: 17 [#1] ARM |PC is at dsps_suspend+0x18/0x9c [musb_dsps] |LR is at dsps_suspend+0x18/0x9c [musb_dsps] |pc : [] lr : [] psr: a0000013 |sp : cbd97e00 ip : c0af4394 fp : 00000000 |r10: c0831d90 r9 : 00000002 r8 : cf6da410 |r7 : c03ba4dc r6 : bf08f224 r5 : 00000000 r4 : cbc5fcd0 |r3 : bf08e250 r2 : bf08f264 r1 : cf6da410 r0 : 00000000 |[] (dsps_suspend [musb_dsps]) from [] (platform_pm_suspend+0x2c/0x54) |Code: e1a04000 e9900041 e2800010 eb4caa8e (e59053a4) because platform_get_drvdata(glue->musb) returns a NULL pointer as long as the device is not fully probed. Tested-by: George Cherian Signed-off-by: Sebastian Andrzej Siewior Signed-off-by: Felipe Balbi --- drivers/usb/musb/musb_dsps.c | 14 ++++++++++++-- 1 file changed, 12 insertions(+), 2 deletions(-) diff --git a/drivers/usb/musb/musb_dsps.c b/drivers/usb/musb/musb_dsps.c index b18f8d5e4f98..48bc09e7b83b 100644 --- a/drivers/usb/musb/musb_dsps.c +++ b/drivers/usb/musb/musb_dsps.c @@ -868,9 +868,15 @@ static int dsps_suspend(struct device *dev) struct dsps_glue *glue = dev_get_drvdata(dev); const struct dsps_musb_wrapper *wrp = glue->wrp; struct musb *musb = platform_get_drvdata(glue->musb); - void __iomem *mbase = musb->ctrl_base; + void __iomem *mbase; del_timer_sync(&glue->timer); + + if (!musb) + /* This can happen if the musb device is in -EPROBE_DEFER */ + return 0; + + mbase = musb->ctrl_base; glue->context.control = dsps_readl(mbase, wrp->control); glue->context.epintr = dsps_readl(mbase, wrp->epintr_set); glue->context.coreintr = dsps_readl(mbase, wrp->coreintr_set); @@ -887,8 +893,12 @@ static int dsps_resume(struct device *dev) struct dsps_glue *glue = dev_get_drvdata(dev); const struct dsps_musb_wrapper *wrp = glue->wrp; struct musb *musb = platform_get_drvdata(glue->musb); - void __iomem *mbase = musb->ctrl_base; + void __iomem *mbase; + + if (!musb) + return 0; + mbase = musb->ctrl_base; dsps_writel(mbase, wrp->control, glue->context.control); dsps_writel(mbase, wrp->epintr_set, glue->context.epintr); dsps_writel(mbase, wrp->coreintr_set, glue->context.coreintr); -- GitLab