Hi Marek, On 7/15/2020 12:42 PM, Marek Szyprowski wrote: > Hi Minas, > > On 14.07.2020 14:32, Minas Harutyunyan wrote: >> On 7/14/2020 12:48 PM, Marek Szyprowski wrote: >>> When gadget registration fails, one should not call usb_del_gadget_udc(). >>> Ensure this by setting gadget->udc to NULL. Also in case of a failure >> I was able to reproduce issue. I'm Ok with this fix. >> >>> there is no need to disable low-level hardware, so return immiedetly >>> instead of jumping to error_init label. >>> >> Why do you think that disable low-level hardware not required which was >> enabled before? Also for some platforms required to call >> regulator_disable() which was enabled earlier in probe function. >> So, I suggest to keep jump to error_init label. > > If I keep the jump to error_init label, then there is unbalanced call to > dwc2_lowlevel_hw_disable(). usb_add_gadget_udc() can fail in 2 places: > on gadget->bind() or during udc_start(). In the first case, the HW was > not yet enabled, so there is no need to disable it. In the latter one, > the error might be returned only from the dwc2_lowlevel_hw_enable(), so > again there is no need to call dwc2_lowlevel_hw_disable(). > > If I keep the "goto error_init;" line, I get the following errors: > > dwc2 12480000.hsotg: dwc2_check_params: Invalid parameter besl=1 > dwc2 12480000.hsotg: dwc2_check_params: Invalid parameter > g_np_tx_fifo_size=1024 > dwc2 12480000.hsotg: EPs: 16, dedicated fifos, 7808 entries in SPRAM > Mass Storage Function, version: 2009/09/11 > LUN: removable file: (no medium) > no file given for LUN0 > g_mass_storage 12480000.hsotg: failed to start g_mass_storage: -22 > ------------[ cut here ]------------ > WARNING: CPU: 3 PID: 49 at drivers/clk/clk.c:958 > clk_core_disable+0x1e4/0x314 > usb_device already disabled > Modules linked in: > CPU: 3 PID: 49 Comm: kworker/3:1 Not tainted > 5.8.0-rc5-next-20200714-00003-g105f360ba595-dirty #8758 > Hardware name: Samsung Exynos (Flattened Device Tree) > Workqueue: events deferred_probe_work_func > [<c011184c>] (unwind_backtrace) from [<c010d250>] (show_stack+0x10/0x14) > [<c010d250>] (show_stack) from [<c051b8fc>] (dump_stack+0xbc/0xe8) > [<c051b8fc>] (dump_stack) from [<c0126ed8>] (__warn+0xf0/0x108) > [<c0126ed8>] (__warn) from [<c0126f64>] (warn_slowpath_fmt+0x74/0xb8) > [<c0126f64>] (warn_slowpath_fmt) from [<c056c338>] > (clk_core_disable+0x1e4/0x314) > [<c056c338>] (clk_core_disable) from [<c056c480>] > (clk_core_disable_lock+0x18/0x24) > [<c056c480>] (clk_core_disable_lock) from [<c073f9d4>] > (__dwc2_lowlevel_hw_disable+0x3c/0xa0) > [<c073f9d4>] (__dwc2_lowlevel_hw_disable) from [<c0740188>] > (dwc2_driver_probe+0x2d4/0x6ac) > [<c0740188>] (dwc2_driver_probe) from [<c0653640>] > (platform_drv_probe+0x6c/0xa4) > [<c0653640>] (platform_drv_probe) from [<c0650bdc>] > (really_probe+0x200/0x4fc) > [<c0650bdc>] (really_probe) from [<c0651040>] > (driver_probe_device+0x78/0x1fc) > [<c0651040>] (driver_probe_device) from [<c064ea78>] > (bus_for_each_drv+0x74/0xb8) > [<c064ea78>] (bus_for_each_drv) from [<c065093c>] > (__device_attach+0xd4/0x16c) > [<c065093c>] (__device_attach) from [<c064fa3c>] > (bus_probe_device+0x88/0x90) > [<c064fa3c>] (bus_probe_device) from [<c064ff54>] > (deferred_probe_work_func+0x3c/0xd0) > [<c064ff54>] (deferred_probe_work_func) from [<c0148a5c>] > (process_one_work+0x234/0x7dc) > [<c0148a5c>] (process_one_work) from [<c0149048>] (worker_thread+0x44/0x51c) > [<c0149048>] (worker_thread) from [<c015039c>] (kthread+0x158/0x1a0) > [<c015039c>] (kthread) from [<c0100114>] (ret_from_fork+0x14/0x20) > Exception stack(0xee923fb0 to 0xee923ff8) > ... > irq event stamp: 36966 > hardirqs last enabled at (36965): [<c02b92d8>] kfree+0x1a4/0x3f0 > hardirqs last disabled at (36966): [<c0569edc>] clk_enable_lock+0x14/0x134 > softirqs last enabled at (36814): [<c010174c>] __do_softirq+0x50c/0x608 > softirqs last disabled at (36803): [<c0130218>] irq_exit+0x168/0x16c > ---[ end trace f55f4b28f3080c12 ]--- > ------------[ cut here ]------------ > WARNING: CPU: 3 PID: 49 at drivers/clk/clk.c:817 > clk_core_unprepare+0x33c/0x470 > usb_device already unprepared > Modules linked in: > CPU: 3 PID: 49 Comm: kworker/3:1 Tainted: G W > 5.8.0-rc5-next-20200714-00003-g105f360ba595-dirty #8758 > Hardware name: Samsung Exynos (Flattened Device Tree) > Workqueue: events deferred_probe_work_func > [<c011184c>] (unwind_backtrace) from [<c010d250>] (show_stack+0x10/0x14) > [<c010d250>] (show_stack) from [<c051b8fc>] (dump_stack+0xbc/0xe8) > [<c051b8fc>] (dump_stack) from [<c0126ed8>] (__warn+0xf0/0x108) > [<c0126ed8>] (__warn) from [<c0126f64>] (warn_slowpath_fmt+0x74/0xb8) > [<c0126f64>] (warn_slowpath_fmt) from [<c056dcb8>] > (clk_core_unprepare+0x33c/0x470) > [<c056dcb8>] (clk_core_unprepare) from [<c056de10>] > (clk_unprepare+0x24/0x2c) > [<c056de10>] (clk_unprepare) from [<c073f9dc>] > (__dwc2_lowlevel_hw_disable+0x44/0xa0) > [<c073f9dc>] (__dwc2_lowlevel_hw_disable) from [<c0740188>] > (dwc2_driver_probe+0x2d4/0x6ac) > [<c0740188>] (dwc2_driver_probe) from [<c0653640>] > (platform_drv_probe+0x6c/0xa4) > [<c0653640>] (platform_drv_probe) from [<c0650bdc>] > (really_probe+0x200/0x4fc) > [<c0650bdc>] (really_probe) from [<c0651040>] > (driver_probe_device+0x78/0x1fc) > [<c0651040>] (driver_probe_device) from [<c064ea78>] > (bus_for_each_drv+0x74/0xb8) > [<c064ea78>] (bus_for_each_drv) from [<c065093c>] > (__device_attach+0xd4/0x16c) > [<c065093c>] (__device_attach) from [<c064fa3c>] > (bus_probe_device+0x88/0x90) > [<c064fa3c>] (bus_probe_device) from [<c064ff54>] > (deferred_probe_work_func+0x3c/0xd0) > [<c064ff54>] (deferred_probe_work_func) from [<c0148a5c>] > (process_one_work+0x234/0x7dc) > [<c0148a5c>] (process_one_work) from [<c0149048>] (worker_thread+0x44/0x51c) > [<c0149048>] (worker_thread) from [<c015039c>] (kthread+0x158/0x1a0) > [<c015039c>] (kthread) from [<c0100114>] (ret_from_fork+0x14/0x20) > Exception stack(0xee923fb0 to 0xee923ff8) > ... > irq event stamp: 37073 > hardirqs last enabled at (37081): [<c019d624>] console_unlock+0x430/0x6cc > hardirqs last disabled at (37108): [<c019d348>] console_unlock+0x154/0x6cc > softirqs last enabled at (37124): [<c010174c>] __do_softirq+0x50c/0x608 > softirqs last disabled at (37135): [<c0130218>] irq_exit+0x168/0x16c > ---[ end trace f55f4b28f3080c13 ]--- > ------------[ cut here ]------------ > WARNING: CPU: 3 PID: 49 at drivers/regulator/core.c:2603 > _regulator_disable+0x180/0x1d8 > unbalanced disables for VUOTG_3.0V > Modules linked in: > CPU: 3 PID: 49 Comm: kworker/3:1 Tainted: G W > 5.8.0-rc5-next-20200714-00003-g105f360ba595-dirty #8758 > Hardware name: Samsung Exynos (Flattened Device Tree) > Workqueue: events deferred_probe_work_func > [<c011184c>] (unwind_backtrace) from [<c010d250>] (show_stack+0x10/0x14) > [<c010d250>] (show_stack) from [<c051b8fc>] (dump_stack+0xbc/0xe8) > [<c051b8fc>] (dump_stack) from [<c0126ed8>] (__warn+0xf0/0x108) > [<c0126ed8>] (__warn) from [<c0126f64>] (warn_slowpath_fmt+0x74/0xb8) > [<c0126f64>] (warn_slowpath_fmt) from [<c0585e78>] > (_regulator_disable+0x180/0x1d8) > [<c0585e78>] (_regulator_disable) from [<c0585f04>] > (regulator_disable+0x34/0xe0) > [<c0585f04>] (regulator_disable) from [<c0587ef8>] > (regulator_bulk_disable+0x28/0xb0) > [<c0587ef8>] (regulator_bulk_disable) from [<c0740188>] > (dwc2_driver_probe+0x2d4/0x6ac) > [<c0740188>] (dwc2_driver_probe) from [<c0653640>] > (platform_drv_probe+0x6c/0xa4) > [<c0653640>] (platform_drv_probe) from [<c0650bdc>] > (really_probe+0x200/0x4fc) > [<c0650bdc>] (really_probe) from [<c0651040>] > (driver_probe_device+0x78/0x1fc) > [<c0651040>] (driver_probe_device) from [<c064ea78>] > (bus_for_each_drv+0x74/0xb8) > [<c064ea78>] (bus_for_each_drv) from [<c065093c>] > (__device_attach+0xd4/0x16c) > [<c065093c>] (__device_attach) from [<c064fa3c>] > (bus_probe_device+0x88/0x90) > [<c064fa3c>] (bus_probe_device) from [<c064ff54>] > (deferred_probe_work_func+0x3c/0xd0) > [<c064ff54>] (deferred_probe_work_func) from [<c0148a5c>] > (process_one_work+0x234/0x7dc) > [<c0148a5c>] (process_one_work) from [<c0149048>] (worker_thread+0x44/0x51c) > [<c0149048>] (worker_thread) from [<c015039c>] (kthread+0x158/0x1a0) > [<c015039c>] (kthread) from [<c0100114>] (ret_from_fork+0x14/0x20) > Exception stack(0xee923fb0 to 0xee923ff8) > ... > irq event stamp: 37243 > hardirqs last enabled at (37251): [<c019d624>] console_unlock+0x430/0x6cc > hardirqs last disabled at (37274): [<c0ac0790>] __schedule+0xd8/0x860 > softirqs last enabled at (37270): [<c010174c>] __do_softirq+0x50c/0x608 > softirqs last disabled at (37291): [<c0130218>] irq_exit+0x168/0x16c > ---[ end trace f55f4b28f3080c14 ]--- > Failed to disable vusb_a: -5 > dwc2: probe of 12480000.hsotg failed with error -22 > 8<--- cut here --- > Unable to handle kernel NULL pointer dereference at virtual address 00000004 > pgd = (ptrval) > [00000004] *pgd=00000000 > Internal error: Oops: 5 [#1] PREEMPT SMP ARM > Modules linked in: > CPU: 3 PID: 87 Comm: kworker/3:2 Tainted: G W > 5.8.0-rc5-next-20200714-00003-g105f360ba595-dirty #8758 > Hardware name: Samsung Exynos (Flattened Device Tree) > Workqueue: 0x0 (rcu_gp) > PC is at process_one_work+0x44/0x7dc > LR is at 0xedc226d0 > ... > Process kworker/3:2 (pid: 87, stack limit = 0x(ptrval)) > Stack: (0xeda03f00 to 0xeda04000) > ... > [<c014886c>] (process_one_work) from [<c0149048>] (worker_thread+0x44/0x51c) > [<c0149048>] (worker_thread) from [<c015039c>] (kthread+0x158/0x1a0) > [<c015039c>] (kthread) from [<c0100114>] (ret_from_fork+0x14/0x20) > Exception stack(0xeda03fb0 to 0xeda03ff8) > ... > ---[ end trace f55f4b28f3080c15 ]--- > note: kworker/3:2[87] exited with preempt_count 1 > > Best regards > I guess you build driver in (hsotg->dr_mode == USB_DR_MODE_PERIPHERAL) and this is why call of dwc2_lowlevel_hw_disable() at 'error:' label create issue. Could you please test on your setup follow implementation: ... error: if (hsotg->dr_mode != USB_DR_MODE_PERIPHERAL) dwc2_lowlevel_hw_disable(hsotg); return retval; } ... Thanks, Minas
