Since commit ddcad7e9068eb omap2_mcspi_set_cs() is called without runtime power management requested. Thus the below kernel oops may be generated if a device is accessed after the runtime power management timeout. This patch fixes the problem by requesting runtime power management in omap2_mcspi_set_cs(). [ 13.933959] Unhandled fault: external abort on non-linefetch (0x1028) at 0xfa09802c [ 13.940490] pgd = cfb38000 [ 13.946594] [fa09802c] *pgd=48011452(bad) [ 13.952758] Internal error: : 1028 [#1] PREEMPT ARM [ 13.958862] Modules linked in: tsc2005(+) omap_sham twl4030_wdt omap_wdt [ 13.965332] CPU: 0 PID: 183 Comm: modprobe Not tainted 4.2.0-rc1+ #363 [ 13.971801] Hardware name: Nokia RX-51 board [ 13.978302] task: cf572300 ti: cb1f2000 task.ti: cb1f2000 [ 13.984924] PC is at omap2_mcspi_set_cs+0x44/0x4c [ 13.991485] LR is at spi_set_cs+0x5c/0x60 [ 13.997985] pc : [<c02bd3ac>] lr : [<c02baecc>] psr: 20000013 [ 13.997985] sp : cb1f3dd0 ip : 00000001 fp : 00000004 [ 14.011260] r10: cfce5be8 r9 : 00000fff r8 : c0654f98 [ 14.017913] r7 : 00000000 r6 : 00000000 r5 : 00000000 r4 : 00000000 [ 14.024505] r3 : 200103dc r2 : fa098000 r1 : 00000001 r0 : cf09bc00 [ 14.031036] Flags: nzCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment user [ 14.037689] Control: 10c5387d Table: 8fb38019 DAC: 00000015 [ 14.044403] Process modprobe (pid: 183, stack limit = 0xcb1f2210) [ 14.051300] Stack: (0xcb1f3dd0 to 0xcb1f4000) [ 14.058105] 3dc0: cf09bc00 c02bafa4 cf09bc00 cf09bc00 [ 14.065277] 3de0: bf013444 bf01254c cf0e2230 cf0e2230 00000001 c0654f98 00000fff 00000fff [ 14.072570] 3e00: 00000008 00000002 00000118 00001f40 00000031 cf09bc00 ffffffed bf013444 [ 14.080078] 3e20: 00000031 c0654f98 cb1f2000 00000000 00000000 c02bb5c0 cf09bc00 00000000 [ 14.087738] 3e40: bf013454 c027a2f4 00000000 cf09bc00 bf013454 bf013454 00000000 c027a594 [ 14.095367] 3e60: 00000000 cf09bc00 cf09bc34 c027a60c bf013454 cb1f3e80 c027a5ac c0278ec8 [ 14.102935] 3e80: cf972c4c cf09d630 bf013454 bf013454 cbb55300 c06848d8 00000000 c0279c84 [ 14.110473] 3ea0: bf01327c bf01327d 00000000 bf013454 cb889180 00000000 c0654f98 c027b0c8 [ 14.117980] 3ec0: 00000000 bf015000 cb889180 c00095b0 0040003e cfe6a080 0040003f 00000000 [ 14.125457] 3ee0: 00080000 cfcf9000 cb1f2000 60000013 0040003e cbf1bbc0 00000000 00000001 [ 14.132843] 3f00: bf0134cc cb1f2000 bf0134c0 cb1f3f58 00000000 c04352d0 cf801f00 000000d0 [ 14.140136] 3f20: bf0134c0 bf0134c0 0000416c cb889040 00000080 c000ebe4 cb1f2000 c0089f68 [ 14.147308] 3f40: bf0134c0 cbf1bc00 001a9193 0000416c 001f8d20 c008ab30 d0b10000 0000416c [ 14.154571] 3f60: d0b1267c d0b1252b d0b13514 000016c0 00001ad0 00000000 00000000 00000000 [ 14.161865] 3f80: 0000001f 00000020 00000017 00000014 00000012 00000000 00201208 00000000 [ 14.169097] 3fa0: 00000000 c000ea60 00201208 00000000 001f8d20 0000416c 001a9193 00000000 [ 14.176177] 3fc0: 00201208 00000000 00000000 00000080 00208c20 001a9193 bee09e98 00000000 [ 14.183197] 3fe0: b6f742b4 bee09ae4 000153f0 000093e4 60000010 001f8d20 72757463 69665f65 [ 14.190277] [<c02bd3ac>] (omap2_mcspi_set_cs) from [<c02baecc>] (spi_set_cs+0x5c/0x60) [ 14.197479] [<c02baecc>] (spi_set_cs) from [<c02bafa4>] (spi_setup+0xd4/0x10c) [ 14.204833] [<c02bafa4>] (spi_setup) from [<bf01254c>] (tsc2005_probe+0x104/0x484 [tsc2005]) [ 14.212249] [<bf01254c>] (tsc2005_probe [tsc2005]) from [<c02bb5c0>] (spi_drv_probe+0x50/0x6c) [ 14.219818] [<c02bb5c0>] (spi_drv_probe) from [<c027a2f4>] (really_probe+0xd4/0x230) [ 14.227478] [<c027a2f4>] (really_probe) from [<c027a594>] (driver_probe_device+0x30/0x48) [ 14.235290] [<c027a594>] (driver_probe_device) from [<c027a60c>] (__driver_attach+0x60/0x84) [ 14.243286] [<c027a60c>] (__driver_attach) from [<c0278ec8>] (bus_for_each_dev+0x50/0x84) [ 14.251281] [<c0278ec8>] (bus_for_each_dev) from [<c0279c84>] (bus_add_driver+0xcc/0x1e0) [ 14.259246] [<c0279c84>] (bus_add_driver) from [<c027b0c8>] (driver_register+0x9c/0xe0) [ 14.267272] [<c027b0c8>] (driver_register) from [<c00095b0>] (do_one_initcall+0x100/0x1b0) [ 14.275421] [<c00095b0>] (do_one_initcall) from [<c0089f68>] (do_init_module+0x58/0x1bc) [ 14.283477] [<c0089f68>] (do_init_module) from [<c008ab30>] (SyS_init_module+0x54/0x64) [ 14.291412] [<c008ab30>] (SyS_init_module) from [<c000ea60>] (ret_fast_syscall+0x0/0x3c) [ 14.299407] Code: e5823018 e5902188 e5922000 e582302c (e592302c) [ 14.307403] ---[ end trace d21553dcaefcb5ac ]--- Reported-By: Pali Rohár <pali.rohar@xxxxxxxxx> Fixes: ddcad7e9068eb (spi: omap2-mcspi: Fix native cs with new set_cs) Tested-By: Pavel Machek <pavel@xxxxxx> Signed-off-by: Sebastian Reichel <sre@xxxxxxxxxx> --- Hi Mark, Previous discussion about this patch happened in the following thread: https://lkml.org/lkml/2015/7/11/98 Michael also tested the patch, but have not explicitly written an Tested-By, so you may want to wait for feedback from him. The patch should be sent for 4.2-rc, which introduced the regression. -- Sebastian --- drivers/spi/spi-omap2-mcspi.c | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/drivers/spi/spi-omap2-mcspi.c b/drivers/spi/spi-omap2-mcspi.c index 5867384..3d09e0b 100644 --- a/drivers/spi/spi-omap2-mcspi.c +++ b/drivers/spi/spi-omap2-mcspi.c @@ -245,6 +245,7 @@ static void omap2_mcspi_set_enable(const struct spi_device *spi, int enable) static void omap2_mcspi_set_cs(struct spi_device *spi, bool enable) { + struct omap2_mcspi *mcspi = spi_master_get_devdata(spi->master); u32 l; /* The controller handles the inverted chip selects @@ -255,6 +256,12 @@ static void omap2_mcspi_set_cs(struct spi_device *spi, bool enable) enable = !enable; if (spi->controller_state) { + int err = pm_runtime_get_sync(mcspi->dev); + if (err < 0) { + dev_err(mcspi->dev, "failed to get sync: %d\n", err); + return; + } + l = mcspi_cached_chconf0(spi); if (enable) @@ -263,6 +270,9 @@ static void omap2_mcspi_set_cs(struct spi_device *spi, bool enable) l |= OMAP2_MCSPI_CHCONF_FORCE; mcspi_write_chconf0(spi, l); + + pm_runtime_mark_last_busy(mcspi->dev); + pm_runtime_put_autosuspend(mcspi->dev); } } -- 2.1.4 -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html