Hello With the new designware DMA controller options i am getting the following error message on startup Have an ASUS t100ta baytrail system, which uses slave on the I2C BUS ------------[ cut here ]------------ [ 0.398332] WARNING: CPU: 0 PID: 1 at drivers/dma/dmaengine.c:830 dma_async_device_register+0xd4/0x4f0() [ 0.398346] this driver doesn't support generic slave capabilities reporting [ 0.398355] Modules linked in: [ 0.398369] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 3.19.0-rc2-next-20150105 #1 [ 0.398381] Hardware name: ASUSTeK COMPUTER INC. T100TA/T100TA, BIOS T100TA.313 08/13/2014 [ 0.398394] 00000000 00000000 f4d21d2c c16e97d7 f4d21d70 f4d21d60 c1053f5c c19630e8 [ 0.398418] f4d21d8c 00000001 c193f781 0000033e c13eb054 0000033e c13eb054 f4fa7e0c [ 0.398440] f4fc118c c13f8650 f4d21d78 c1053fc4 00000009 f4d21d70 c19630e8 f4d21d8c [ 0.398463] Call Trace: [ 0.398479] [<c16e97d7>] dump_stack+0x41/0x52 [ 0.398495] [<c1053f5c>] warn_slowpath_common+0x8c/0xc0 [ 0.398507] [<c13eb054>] ? dma_async_device_register+0xd4/0x4f0 [ 0.398520] [<c13eb054>] ? dma_async_device_register+0xd4/0x4f0 [ 0.398533] [<c13f8650>] ? dwc_scan_descriptors+0x390/0x390 [ 0.398544] [<c1053fc4>] warn_slowpath_fmt+0x34/0x40 [ 0.398557] [<c13eb054>] dma_async_device_register+0xd4/0x4f0 [ 0.398568] [<c13f7580>] ? dwc_resume+0x40/0x40 [ 0.398581] [<c10a7e23>] ? request_threaded_irq+0xa3/0x130 [ 0.398593] [<c13f8c51>] dw_dma_probe+0x511/0x620 [ 0.398606] [<c13f9397>] dw_probe+0x107/0x1e0 [ 0.398619] [<c120c4d3>] ? sysfs_do_create_link_sd.isra.2+0x53/0xb0 [ 0.398633] [<c1450ffd>] platform_drv_probe+0x2d/0x90 [ 0.398645] [<c144eac2>] ? driver_sysfs_add+0x62/0x80 [ 0.398656] [<c144f0b4>] driver_probe_device+0x94/0x3a0 [ 0.398670] [<c13b6b14>] ? acpi_driver_match_device+0x93/0xa1 [ 0.398682] [<c120c268>] ? sysfs_create_dir_ns+0x38/0x80 [ 0.398694] [<c1451267>] ? platform_match+0x37/0x90 [ 0.398705] [<c144f471>] __driver_attach+0x71/0x80 [ 0.398716] [<c144f400>] ? __device_attach+0x40/0x40 [ 0.398729] [<c144d40f>] bus_for_each_dev+0x4f/0x80 [ 0.398741] [<c144eb9f>] driver_attach+0x1f/0x30 [ 0.398751] [<c144f400>] ? __device_attach+0x40/0x40 [ 0.398764] [<c144e817>] bus_add_driver+0x167/0x230 [ 0.398776] [<c1acd579>] ? ioat_init_module+0xa1/0xa1 [ 0.398788] [<c1acd579>] ? ioat_init_module+0xa1/0xa1 [ 0.398799] [<c144fb8e>] driver_register+0x5e/0xf0 [ 0.398812] [<c1340b31>] ? kvasprintf+0x41/0x50 [ 0.398823] [<c1450f63>] __platform_driver_register+0x43/0x50 [ 0.398836] [<c1acd588>] dw_init+0xf/0x11 [ 0.398847] [<c1000496>] do_one_initcall+0xc6/0x200 [ 0.398859] [<c1acd579>] ? ioat_init_module+0xa1/0xa1 [ 0.398873] [<c1a954f9>] ? repair_env_string+0x12/0x54 [ 0.398886] [<c1a95c94>] kernel_init_freeable+0x152/0x1d4 [ 0.398899] [<c16e2e31>] kernel_init+0x11/0xf0 [ 0.398912] [<c16ef981>] ret_from_kernel_thread+0x21/0x30 [ 0.398923] [<c16e2e20>] ? rest_init+0x70/0x70 [ 0.398947] ---[ end trace eac12ef61082285e ]--- [ 0.399330] dw_dmac INTL9C60:00: DesignWare DMA Controller, 8 channels [ 0.399610] ------------[ cut here ]------------ [ 0.399626] WARNING: CPU: 0 PID: 1 at drivers/dma/dmaengine.c:830 dma_async_device_register+0xd4/0x4f0() [ 0.399638] this driver doesn't support generic slave capabilities reporting [ 0.399647] Modules linked in: [ 0.399659] CPU: 0 PID: 1 Comm: swapper/0 Tainted: G W 3.19.0-rc2-next-20150105 #1 [ 0.399672] Hardware name: ASUSTeK COMPUTER INC. T100TA/T100TA, BIOS T100TA.313 08/13/2014 [ 0.399684] 00000000 00000000 f4d21d2c c16e97d7 f4d21d70 f4d21d60 c1053f5c c19630e8 [ 0.399707] f4d21d8c 00000001 c193f781 0000033e c13eb054 0000033e c13eb054 f4fd600c [ 0.399729] f4fc124c c13f8650 f4d21d78 c1053fc4 00000009 f4d21d70 c19630e8 f4d21d8c [ 0.399752] Call Trace: [ 0.399763] [<c16e97d7>] dump_stack+0x41/0x52 [ 0.399776] [<c1053f5c>] warn_slowpath_common+0x8c/0xc0 [ 0.399789] [<c13eb054>] ? dma_async_device_register+0xd4/0x4f0 [ 0.399801] [<c13eb054>] ? dma_async_device_register+0xd4/0x4f0 [ 0.399814] [<c13f8650>] ? dwc_scan_descriptors+0x390/0x390 [ 0.399825] [<c1053fc4>] warn_slowpath_fmt+0x34/0x40 [ 0.399837] [<c13eb054>] dma_async_device_register+0xd4/0x4f0 [ 0.399849] [<c13f7580>] ? dwc_resume+0x40/0x40 [ 0.399861] [<c10a7e23>] ? request_threaded_irq+0xa3/0x130 [ 0.399873] [<c13f8c51>] dw_dma_probe+0x511/0x620 [ 0.399885] [<c13f9397>] dw_probe+0x107/0x1e0 [ 0.399897] [<c120c4d3>] ? sysfs_do_create_link_sd.isra.2+0x53/0xb0 [ 0.399910] [<c1450ffd>] platform_drv_probe+0x2d/0x90 [ 0.399921] [<c144eac2>] ? driver_sysfs_add+0x62/0x80 [ 0.399933] [<c144f0b4>] driver_probe_device+0x94/0x3a0 [ 0.399945] [<c13b6b14>] ? acpi_driver_match_device+0x93/0xa1 [ 0.399957] [<c120c268>] ? sysfs_create_dir_ns+0x38/0x80 [ 0.399969] [<c1451267>] ? platform_match+0x37/0x90 [ 0.399981] [<c144f471>] __driver_attach+0x71/0x80 [ 0.399992] [<c144f400>] ? __device_attach+0x40/0x40 [ 0.400004] [<c144d40f>] bus_for_each_dev+0x4f/0x80 [ 0.400015] [<c144eb9f>] driver_attach+0x1f/0x30 [ 0.400026] [<c144f400>] ? __device_attach+0x40/0x40 [ 0.400038] [<c144e817>] bus_add_driver+0x167/0x230 [ 0.400051] [<c1acd579>] ? ioat_init_module+0xa1/0xa1 [ 0.400063] [<c1acd579>] ? ioat_init_module+0xa1/0xa1 [ 0.400074] [<c144fb8e>] driver_register+0x5e/0xf0 [ 0.400085] [<c1340b31>] ? kvasprintf+0x41/0x50 [ 0.400097] [<c1450f63>] __platform_driver_register+0x43/0x50 [ 0.400109] [<c1acd588>] dw_init+0xf/0x11 [ 0.400120] [<c1000496>] do_one_initcall+0xc6/0x200 [ 0.400149] [<c1acd579>] ? ioat_init_module+0xa1/0xa1 [ 0.400162] [<c1a954f9>] ? repair_env_string+0x12/0x54 [ 0.400176] [<c1a95c94>] kernel_init_freeable+0x152/0x1d4 [ 0.400189] [<c16e2e31>] kernel_init+0x11/0xf0 [ 0.400201] [<c16ef981>] ret_from_kernel_thread+0x21/0x30 [ 0.400213] [<c16e2e20>] ? rest_init+0x70/0x70 [ 0.400223] ---[ end trace eac12ef61082285f ]--- [ 0.400614] dw_dmac INTL9C60:01: DesignWare DMA Controller, 8 channels seems like it is related to the new i2c Slave functionality that was implemented
I don't think this has anything to do with the I2C slave functionality. "slave" in the error message refers to a DMA channel capability. In fact, looking at the stack trace, I have no reason to believe that this bug is related to I2C at all, this is a DMA engine bug.
I have cc'd both of you to the patch that caused it.. Its all about dmaengine.
Presumably fixed in 4.0-rc1 by: commit 029a40e97d0db269f4a7fc02b0f29f627f628309 Author: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Date: Fri Jan 2 16:17:24 2015 +0200 dmaengine: dw: provide DMA capabilities Please reopen if not.