Hi Minas, On 15.07.2020 15:54, Minas Harutyunyan wrote: > On 7/15/2020 12:42 PM, Marek Szyprowski wrote: >> 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; > } > ... Right, this will work. However, I would also change the order of operations - disabling usb33d regulator should be done after disabling lowlevel hardware to properly pair with the enable operations. While playing with this I've also found an issue in UDC core: https://lore.kernel.org/linux-usb/20200716115525.27519-1-m.szyprowski@xxxxxxxxxxx/T/#u Best regards -- Marek Szyprowski, PhD Samsung R&D Institute Poland
