RE: [PATCH V7 1/7] spi: Add stacked and parallel memories support in SPI core

["Mahapatra, Amit Kumar" <amit.kumar-mahapatra@xxxxxxx>]

Hello Stefan,

> -----Original Message-----
> From: Stefan Binding <sbinding@xxxxxxxxxxxxxxxxxxxxx>
> Sent: Tuesday, April 25, 2023 5:50 PM
> To: Mahapatra, Amit Kumar <amit.kumar-mahapatra@xxxxxxx>;
> broonie@xxxxxxxxxx; tudor.ambarus@xxxxxxxxxx; pratyush@xxxxxxxxxx;
> michael@xxxxxxxx; miquel.raynal@xxxxxxxxxxx; richard@xxxxxx;
> vigneshr@xxxxxx
> Cc: git (AMD-Xilinx) <git@xxxxxxx>; linux-spi@xxxxxxxxxxxxxxx; linux-
> kernel@xxxxxxxxxxxxxxx; linux-mtd@xxxxxxxxxxxxxxxxxxx;
> nicolas.ferre@xxxxxxxxxxxxx; alexandre.belloni@xxxxxxxxxxx;
> claudiu.beznea@xxxxxxxxxxxxx; Simek, Michal <michal.simek@xxxxxxx>;
> linux-arm-kernel@xxxxxxxxxxxxxxxxxxx; amitrkcian2002@xxxxxxxxx;
> patches@xxxxxxxxxxxxxxxxxxxxx; vitalyr@xxxxxxxxxxxxxxxxxxxxx
> Subject: Re: [PATCH V7 1/7] spi: Add stacked and parallel memories support
> in SPI core
> 
> Hi,
> 
> On 20/04/2023 10:04, Mahapatra, Amit Kumar wrote:
> > Hello Stefan,
> >
> >> -----Original Message-----
> >> From: Stefan Binding <sbinding@xxxxxxxxxxxxxxxxxxxxx>
> >> Sent: Wednesday, April 12, 2023 8:33 PM
> >> To: Mahapatra, Amit Kumar <amit.kumar-mahapatra@xxxxxxx>;
> >> broonie@xxxxxxxxxx; tudor.ambarus@xxxxxxxxxx; pratyush@xxxxxxxxxx;
> >> michael@xxxxxxxx; miquel.raynal@xxxxxxxxxxx; richard@xxxxxx;
> >> vigneshr@xxxxxx
> >> Cc: git (AMD-Xilinx) <git@xxxxxxx>; linux-spi@xxxxxxxxxxxxxxx; linux-
> >> kernel@xxxxxxxxxxxxxxx; linux-mtd@xxxxxxxxxxxxxxxxxxx;
> >> nicolas.ferre@xxxxxxxxxxxxx; alexandre.belloni@xxxxxxxxxxx;
> >> claudiu.beznea@xxxxxxxxxxxxx; Simek, Michal
> <michal.simek@xxxxxxx>;
> >> linux-arm-kernel@xxxxxxxxxxxxxxxxxxx; amitrkcian2002@xxxxxxxxx;
> >> patches@xxxxxxxxxxxxxxxxxxxxx; vitalyr@xxxxxxxxxxxxxxxxxxxxx
> >> Subject: Re: [PATCH V7 1/7] spi: Add stacked and parallel memories
> >> support in SPI core
> >>
> >> Hi,
> >>
> >> On 11/04/2023 10:07, Mahapatra, Amit Kumar wrote:
> >>> Hello Stefan,
> >>>
> >>>> -----Original Message-----
> >>>> From: Stefan Binding <sbinding@xxxxxxxxxxxxxxxxxxxxx>
> >>>> Sent: Thursday, April 6, 2023 7:14 PM
> >>>> To: Mahapatra, Amit Kumar <amit.kumar-mahapatra@xxxxxxx>;
> >>>> broonie@xxxxxxxxxx; tudor.ambarus@xxxxxxxxxx; pratyush@xxxxxxxxxx;
> >>>> michael@xxxxxxxx; miquel.raynal@xxxxxxxxxxx; richard@xxxxxx;
> >>>> vigneshr@xxxxxx
> >>>> Cc: git (AMD-Xilinx) <git@xxxxxxx>; linux-spi@xxxxxxxxxxxxxxx;
> >>>> linux- kernel@xxxxxxxxxxxxxxx; linux-mtd@xxxxxxxxxxxxxxxxxxx;
> >>>> nicolas.ferre@xxxxxxxxxxxxx; alexandre.belloni@xxxxxxxxxxx;
> >>>> claudiu.beznea@xxxxxxxxxxxxx; Simek, Michal
> >> <michal.simek@xxxxxxx>;
> >>>> linux-arm-kernel@xxxxxxxxxxxxxxxxxxx; amitrkcian2002@xxxxxxxxx;
> >>>> patches@xxxxxxxxxxxxxxxxxxxxx; vitalyr@xxxxxxxxxxxxxxxxxxxxx
> >>>> Subject: RE: [PATCH V7 1/7] spi: Add stacked and parallel memories
> >>>> support in SPI core
> >>>>
> >>>> Hi,
> >>>>
> >>>>> -----Original Message-----
> >>>>> From: Amit Kumar Mahapatra <amit.kumar-mahapatra@xxxxxxx>
> >>>>> Sent: Thursday, April 6, 2023 7:54 AM
> >>>>> To: broonie@xxxxxxxxxx; tudor.ambarus@xxxxxxxxxx;
> >>>>> pratyush@xxxxxxxxxx; michael@xxxxxxxx; miquel.raynal@xxxxxxxxxxx;
> >>>>> richard@xxxxxx; vigneshr@xxxxxx
> >>>>> Cc: git@xxxxxxx; sbinding@xxxxxxxxxxxxxxxxxxxxx; linux-
> >>>>> spi@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; linux-
> >>>>> mtd@xxxxxxxxxxxxxxxxxxx; nicolas.ferre@xxxxxxxxxxxxx;
> >>>>> alexandre.belloni@xxxxxxxxxxx; claudiu.beznea@xxxxxxxxxxxxx;
> >>>>> michal.simek@xxxxxxx; linux-arm-kernel@xxxxxxxxxxxxxxxxxxx;
> >>>>> amitrkcian2002@xxxxxxxxx; Amit Kumar Mahapatra <amit.kumar-
> >>>>> mahapatra@xxxxxxx>
> >>>>> Subject: [PATCH V7 1/7] spi: Add stacked and parallel memories
> >>>> support
> >>>>> in SPI core
> >>>>>
> >>>>> For supporting multiple CS the SPI device need to be aware of all
> >>>> the CS
> >>>>> values. So, the "chip_select" member in the spi_device structure
> >>>>> is
> >>>> now
> >>>>> an
> >>>>> array that holds all the CS values.
> >>>>>
> >>>>> spi_device structure now has a "cs_index_mask" member. This acts
> >>>>> as
> >>>> an
> >>>>> index to the chip_select array. If nth bit of spi->cs_index_mask
> >>>>> is
> >>>> set
> >>>>> then the driver would assert spi->chip_select[n].
> >>>>>
> >>>>> In parallel mode all the chip selects are asserted/de-asserted
> >>>>> simultaneously and each byte of data is stored in both devices,
> >>>>> the
> >>>> even
> >>>>> bits in one, the odd bits in the other. The split is automatically
> >>>> handled
> >>>>> by the GQSPI controller. The GQSPI controller supports a maximum
> >>>>> of two flashes connected in parallel mode. A
> >>>>> SPI_CONTROLLER_MULTI_CS flag bit is added in the spi
> >>>>> controntroller flags, through
> >>>>> ctlr->flags the spi
> >>>> core
> >>>>> will make sure that the controller is capable of handling multiple
> >>>> chip
> >>>>> selects at once.
> >>>>>
> >>>>> For supporting multiple CS via GPIO the cs_gpiod member of the
> >>>>> spi_device structure is now an array that holds the gpio
> >>>>> descriptor for each chipselect.
> >>>>>
> >>>>> Multi CS support using GPIO is not tested due to unavailability of
> >>>>> necessary hardware setup.
> >>>>>
> >>>>> Multi CS configuration with one native CS and one GPIO CS is not
> >>>>> supported as this configuration could not be tested due to
> >>>>> unavailability of necessary hardware setup.
> >>>> I've tested this chain on a released laptop (HP EliteBook 840 G9)
> >>>> which uses SPI to interface to 2 amps, one amp uses a native CS and
> >>>> the other uses a GPIO CS, and I noticed that when using this chain,
> >>>> the second amp no longer works.
> >>> Thank you for testing this patch series on GPIO CS setup. As I don't
> >>> have a GPIO CS setup, is it possible for you debug the failure and
> >>> share more details/logs where the problem is?
> >>>
> >>> Regards,
> >>> Amit
> >> We are willing and able to debug this failure and share the failure logs.
> >> The first issue that I see is a kernel crash when trying to set the GPIO CS:
> >>
> >> [    2.951658] general protection fault, probably for non-canonical
> >> address
> >> 0xdead000000000122: 0000 [#1] PREEMPT SMP NOPTI [    2.951771] CPU:
> 9
> >> PID: 379 Comm: systemd-udevd Tainted: G A           6.3.0-rc3+ #30 [
> >> 2.951826] Hardware name: HP /896D, BIOS U70 Ver. 89.33.02 10/29/2021
> >> [    2.951882] RIP: 0010:gpiod_set_value_cansleep+0x21/0xa0
> >> [    2.951941] Code: 90 90 90 90 90 90 90 90 90 0f 1f 44 00 00 48 85
> >> ff
> >> 74 3e 55 48 89 e5 41 55 41 89 f5 41 54 49 89 fc 48 81 ff 00 f0 ff ff
> >> 77 2c <48> 8b 3f 48 85 ff 74 53 48 83 bf 68 03 00 00 00 74 34 44 89
> >> ee 4c [    2.952043]
> >> RSP: 0018:ffffc008c0deb928 EFLAGS: 00010287 [    2.952080] RAX:
> >> 0000000000000001 RBX: ffffa0a489534c00 RCX:
> >> 0000000000000000
> >> [    2.952124] RDX: dead000000000122 RSI: 0000000000000001 RDI:
> >> dead000000000122
> >> [    2.952167] RBP: ffffc008c0deb938 R08: 0000000000000000 R09:
> >> ffffc008c0deb868
> >> [    2.952211] R10: ffffffffffffffff R11: 00000000000000b0 R12:
> >> dead000000000122
> >> [    2.952256] R13: 0000000000000001 R14: 0000000000000000 R15:
> >> 0000000000000000
> >> [    2.952299] FS:  00007f7fa5b5b880(0000) GS:ffffa0a81f840000(0000)
> >> knlGS:0000000000000000
> >> [    2.952369] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [
> >> 2.952407] CR2: 000055d648427100 CR3: 000000010e960003 CR4:
> >> 0000000000770ee0
> >> [    2.952451] DR0: 0000000000000000 DR1: 0000000000000000 DR2:
> >> 0000000000000000
> >> [    2.952492] DR3: 0000000000000000 DR6: 00000000ffff07f0 DR7:
> >> 0000000000000400
> >> [    2.952533] PKRU: 55555554
> >> [    2.952561] Call Trace:
> >> [    2.952579]  <TASK>
> >> [    2.952598]  spi_set_cs+0x257/0x4a0 [    2.952630]
> >> spi_setup+0x1a2/0x500 [    2.952667]  __spi_add_device+0x88/0x160 [
> >> 2.952710]  spi_add_device+0x60/0x90 [    2.952738]
> >> smi_spi_probe+0x178/0x370 [serial_multi_instantiate] [    2.952792]
> >> smi_probe+0xcf/0x110 [serial_multi_instantiate] [    2.952854]
> >> platform_probe+0x42/0xb0 [    2.952885]  really_probe+0x1b2/0x420 [
> >> 2.952914]  __driver_probe_device+0x7e/0x180 [    2.952947]
> >> driver_probe_device+0x23/0xa0 [    2.952993]
> >> __driver_attach+0xe4/0x1e0 [    2.953021]  ?
> >> __pfx___driver_attach+0x10/0x10
> >> [    2.953061]  bus_for_each_dev+0x7a/0xd0 [    2.953088]
> >> driver_attach+0x1e/0x30 [    2.953123]  bus_add_driver+0x11c/0x220 [
> >> 2.953150]  driver_register+0x64/0x130 [    2.953174]  ?
> >> __pfx_init_module+0x10/0x10 [serial_multi_instantiate] [    2.953221]
> >> __platform_driver_register+0x1e/0x30
> >> [    2.953251]  smi_driver_init+0x1c/0xff0 [serial_multi_instantiate]
> >> [    2.953310]  do_one_initcall+0x46/0x220 [    2.953339]  ?
> >> kmalloc_trace+0x2a/0xa0 [    2.953375]  do_init_module+0x52/0x220 [
> >> 2.953411]  load_module+0x223c/0x2460 [    2.953450]
> >> __do_sys_finit_module+0xc8/0x140 [    2.953479]  ?
> >> __do_sys_finit_module+0xc8/0x140
> >> [    2.953510]  __x64_sys_finit_module+0x18/0x20 [    2.953538]
> >> do_syscall_64+0x38/0x90 [    2.953574]
> >> entry_SYSCALL_64_after_hwframe+0x72/0xdc
> >> [    2.953606] RIP: 0033:0x7f7fa5d7476d [    2.953639] Code: 00 c3 66
> >> 2e 0f 1f 84 00 00 00 00 00 90 f3 0f 1e fa
> >> 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08
> >> 0f
> >> 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d f3 36 0d 00 f7 d8 64 89 01
> >> 48 [    2.953739] RSP: 002b:00007fff1f8dd3b8 EFLAGS: 00000246
> ORIG_RAX:
> >> 0000000000000139
> >> [    2.956833] RAX: ffffffffffffffda RBX: 000055d648654ab0 RCX:
> >> 00007f7fa5d7476d
> >> [    2.959202] RDX: 0000000000000000 RSI: 00007f7fa5c54ded RDI:
> >> 0000000000000006
> >> [    2.961542] RBP: 0000000000020000 R08: 0000000000000000 R09:
> >> 0000000000000000
> >> [    2.964312] R10: 0000000000000006 R11: 0000000000000246 R12:
> >> 00007f7fa5c54ded
> >> [    2.966694] R13: 0000000000000000 R14: 000055d6483f41a0 R15:
> >> 000055d648654ab0
> >> [    2.967668] resource: resource sanity check: requesting [mem
> >> 0x00000000fedc0000-0x00000000fedcffff], which spans more than pnp
> >> 00:04 [mem 0xfedc0000-0xfedc7fff] [    2.968998]  </TASK> [
> >> 2.971615] caller
> >> igen6_probe+0x178/0x8e0 [igen6_edac] mapping multiple BARs [
> >> 2.975014] Modules linked in: igen6_edac(+) fjes(-)
> >> serial_multi_instantiate(+) int3403_thermal sch_fq_codel
> >> int340x_thermal_zone int3400_thermal intel_hid acpi_thermal_rel
> >> acpi_tad sparse_keymap acpi_pad mac_hid msr parport_pc ppdev lp
> >> parport drm ramoops reed_solomon efi_pstore ip_tables x_tables
> >> autofs4 spi_pxa2xx_platform dw_dmac dw_dmac_core nvme
> intel_lpss_pci
> >> intel_lpss crc32_pclmul thunderbolt i2c_i801 xhci_pci idma64
> >> nvme_core i2c_smbus virt_dma xhci_pci_renesas video wmi
> >> pinctrl_tigerlake [    2.987901] ---[ end trace 0000000000000000 ]---
> [    3.157030] RIP:
> >> 0010:gpiod_set_value_cansleep+0x21/0xa0
> >> [    3.159077] Code: 90 90 90 90 90 90 90 90 90 0f 1f 44 00 00 48 85
> >> ff
> >> 74 3e 55 48 89 e5 41 55 41 89 f5 41 54 49 89 fc 48 81 ff 00 f0 ff ff
> >> 77 2c <48> 8b 3f 48 85 ff 74 53 48 83 bf 68 03 00 00 00 74 34 44 89
> >> ee 4c [    3.161461]
> >> RSP: 0018:ffffc008c0deb928 EFLAGS: 00010287 [    3.164005] RAX:
> >> 0000000000000001 RBX: ffffa0a489534c00 RCX:
> >> 0000000000000000
> >> [    3.166354] RDX: dead000000000122 RSI: 0000000000000001 RDI:
> >> dead000000000122
> >> [    3.168499] RBP: ffffc008c0deb938 R08: 0000000000000000 R09:
> >> ffffc008c0deb868
> >> [    3.170609] R10: ffffffffffffffff R11: 00000000000000b0 R12:
> >> dead000000000122
> >> [    3.172893] R13: 0000000000000001 R14: 0000000000000000 R15:
> >> 0000000000000000
> >> [    3.175335] FS:  00007f7fa5b5b880(0000) GS:ffffa0a81f840000(0000)
> >> knlGS:0000000000000000
> >> [    3.180434] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [
> >> 3.183356] CR2: 000055d648427100 CR3: 000000010e960003 CR4:
> >> 0000000000770ee0
> >> [    3.185107] DR0: 0000000000000000 DR1: 0000000000000000 DR2:
> >> 0000000000000000
> >> [    3.186840] DR3: 0000000000000000 DR6: 00000000ffff07f0 DR7:
> >> 0000000000000400
> >> [    3.188647] PKRU: 55555554
> > Thank you for sharing the logs.
> > As per our analysis the spi->cs_gpiod[0] is getting messed up while
> > setting it in __spi_add_device( ).
> > Is it possible for you to do the following changes on top of this
> > patch series & re-run your test.
> >
> > After applying this patch series, in drivers/spi/spi.c file replace
> > the following code snippet in __spi_add_device( ) function defination.
> >
> > if (ctlr->cs_gpiods) {
> >          for (idx = 0; idx < SPI_CS_CNT_MAX; idx++)
> >                  spi_set_csgpiod(spi, idx,
> > ctlr->cs_gpiods[spi_get_chipselect(spi, idx)]); }
> >
> > with the below code snippet
> >
> > if (ctlr->cs_gpiods) {
> >          for (idx = 0; idx < SPI_CS_CNT_MAX; idx++) {
> >                  if (!(idx != 0 && !spi_get_chipselect(spi, idx)))
> >                          spi_set_csgpiod(spi, idx, ctlr-
> >cs_gpiods[spi_get_chipselect(spi, idx)]);
> >          }
> > }
> >
> > then re-run your test.
> >
> > Regards,
> > Amit
> 
> I'm still seeing a crash on probe:
> 
> [    3.265683] BUG: unable to handle page fault for address:
> 00000000fffedfdd
> [    3.265744] #PF: supervisor read access in kernel mode [    3.265781] #PF:
> error_code(0x0000) - not-present page [    3.265817] PGD 0 P4D 0
> [    3.265840] Oops: 0000 [#1] PREEMPT SMP NOPTI [    3.265865] CPU: 4 PID:
> 385 Comm: systemd-udevd Tainted: G A           6.3.0-rc3+ #32 [    3.265910]
> Hardware name: HP /896D, BIOS U70 Ver. 89.33.02 10/29/2021 [    3.265956]
> RIP: 0010:gpiod_set_raw_value_commit+0x3d/0xf0
> [    3.266007] Code: 48 89 e5 41 55 44 0f b6 ee 41 54 53 48 8b 17 48 2b
> 82 70 03 00 00 4c 8b a2 68 03 00 00 48 c1 f8 03 48 0f af c1 66 90 48 89
> c6 <49> 8b 44 24 60 44 89 ea 4c 89 e7 ff d0 0f 1f 00 5b 41 5c 41 5d 5d
> [    3.266092] RSP: 0018:ffffaad780f6f620 EFLAGS: 00010a03 [    3.266121]
> RAX: 333330b6bdbad102 RBX: ffff9c8d4a5f6800 RCX:
> cccccccccccccccd
> [    3.266156] RDX: ffff9c8d4a5f6d40 RSI: 333330b6bdbad102 RDI:
> ffff9c8d4a5f6d40
> [    3.266192] RBP: ffffaad780f6f638 R08: 00000001018c3789 R09:
> 0000000000000000
> [    3.266228] R10: ffff9c8c4009ee40 R11: 0000000000000000 R12:
> 00000000fffedf7d
> [    3.266264] R13: 0000000000000000 R14: 0000000000000001 R15:
> 0000000000000001
> [    3.266299] FS:  00007f98d04de880(0000) GS:ffff9c90df700000(0000)
> knlGS:0000000000000000
> [    3.266358] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> [    3.266388] CR2: 00000000fffedfdd CR3: 000000010b680003 CR4:
> 0000000000770ee0
> [    3.266422] DR0: 0000000000000000 DR1: 0000000000000000 DR2:
> 0000000000000000
> [    3.266457] DR3: 0000000000000000 DR6: 00000000ffff07f0 DR7:
> 0000000000000400
> [    3.266490] PKRU: 55555554
> [    3.266513] Call Trace:
> [    3.266530]  <TASK>
> [    3.266546]  gpiod_set_value_nocheck+0x5b/0x70
> [    3.266583]  gpiod_set_value_cansleep+0x3e/0xa0
> [    3.266609]  spi_set_cs+0x257/0x4a0
> [    3.266634]  spi_transfer_one_message+0x49/0x740
> [    3.266672]  __spi_pump_transfer_message+0x29b/0x620
> [    3.266712]  __spi_sync+0x26f/0x3b0
> [    3.266735]  spi_write_then_read+0x157/0x210 [    3.266771]  ?
> psi_group_change+0x175/0x3b0 [    3.266802]  regmap_spi_read+0xe/0x20
> [    3.266826]  _regmap_raw_read+0xe1/0x210
> [    3.266861]  _regmap_bus_read+0x3a/0x70
> [    3.266887]  _regmap_read+0x66/0x140
> [    3.266918]  regmap_read+0x3f/0x70
> [    3.266957]  cs35l41_hda_probe+0x553/0xc10 [snd_hda_scodec_cs35l41]
> [    3.267027]  cs35l41_hda_spi_probe+0x62/0x80
> [snd_hda_scodec_cs35l41_spi] [    3.267096]  spi_probe+0x55/0x90
> [    3.267145]  really_probe+0x1b2/0x420
> [    3.267184]  __driver_probe_device+0x7e/0x180
> [    3.267227]  driver_probe_device+0x23/0xa0
> [    3.267287]  __driver_attach+0xe4/0x1e0 [    3.267326]  ?
> __pfx___driver_attach+0x10/0x10
> [    3.267381]  bus_for_each_dev+0x7a/0xd0
> [    3.267406]  driver_attach+0x1e/0x30
> [    3.267437]  bus_add_driver+0x11c/0x220
> [    3.267461]  driver_register+0x64/0x130 [    3.267483]  ?
> __pfx_init_module+0x10/0x10 [snd_hda_scodec_cs35l41_spi]
> [    3.267525]  __spi_register_driver+0xa1/0xd0 [    3.270712]  ?
> __pfx_init_module+0x10/0x10 [snd_hda_scodec_cs35l41_spi]
> [    3.273446]  cs35l41_spi_driver_init+0x1c/0xff0
> [snd_hda_scodec_cs35l41_spi]
> [    3.275119]  do_one_initcall+0x46/0x220 [    3.276828]  ?
> kmalloc_trace+0x2a/0xa0 [    3.279290]  do_init_module+0x52/0x220
> [    3.283593]  load_module+0x223c/0x2460
> [    3.283602]  __do_sys_finit_module+0xc8/0x140 [    3.287883]  ?
> __do_sys_finit_module+0xc8/0x140
> [    3.287907]  __x64_sys_finit_module+0x18/0x20
> [    3.293156]  do_syscall_64+0x38/0x90
> [    3.298937]  entry_SYSCALL_64_after_hwframe+0x72/0xdc
> [    3.298945] RIP: 0033:0x7f98d06f776d
> [    3.319574] Code: 00 c3 66 2e 0f 1f 84 00 00 00 00 00 90 f3 0f 1e fa
> 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f
> 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d f3 36 0d 00 f7 d8 64 89 01 48
> [    3.319579] RSP: 002b:00007ffd988f7a08 EFLAGS: 00000246 ORIG_RAX:
> 0000000000000139
> [    3.319585] RAX: ffffffffffffffda RBX: 000055af06a7d030 RCX:
> 00007f98d06f776d
> [    3.319589] RDX: 0000000000000000 RSI: 00007f98d05d7ded RDI:
> 0000000000000013
> [    3.329520] RBP: 0000000000020000 R08: 0000000000000000 R09:
> 0000000000000000
> [    3.329523] R10: 0000000000000013 R11: 0000000000000246 R12:
> 00007f98d05d7ded
> [    3.329525] R13: 0000000000000000 R14: 000055af06cdd040 R15:
> 000055af06a7d030
> [    3.329531]  </TASK>
> [    3.329533] Modules linked in: snd_hda_intel(+) ttm snd_intel_dspcfg btusb
> rapl snd_seq_midi snd_intel_sdw_acpi libarc4 intel_cstate binfmt_misc
> uvcvideo(+) snd_seq_midi_event btrtl
> snd_hda_scodec_cs35l41_spi(+) snd_hda_codec drm_display_helper
> cdc_ncm(+) videobuf2_vmalloc snd_rawmidi btbcm uvc cdc_ether cec btintel
> videobuf2_memops snd_hda_scodec_cs35l41_i2c snd_hda_core
> videobuf2_v4l2 uas usbnet rc_core snd_hwdep btmtk
> snd_hda_scodec_cs35l41 input_leds mii wmi_bmof videodev snd_seq
> processor_thermal_device_pci bluetooth iwlwifi drm_kms_helper snd_pcm
> snd_hda_cs_dsp_ctls processor_thermal_device mei_me
> videobuf2_common snd_seq_device i2c_algo_bit cs_dsp
> processor_thermal_rfim ecdh_generic usb_storage serio_raw mc
> syscopyarea ecc processor_thermal_mbox ucsi_acpi snd_soc_cs35l41_lib
> 8250_dw mei snd_timer cfg80211 sysfillrect typec_ucsi
> processor_thermal_rapl igen6_edac sysimgblt intel_rapl_common typec snd
> soundcore int3403_thermal int340x_thermal_zone serial_multi_instantiate
> int3400_thermal intel_hid acpi_thermal_rel [    3.338475]  sparse_keymap
> acpi_tad acpi_pad mac_hid sch_fq_codel msr parport_pc ppdev lp parport
> drm ramoops reed_solomon efi_pstore ip_tables x_tables autofs4
> spi_pxa2xx_platform dw_dmac dw_dmac_core intel_lpss_pci nvme
> intel_lpss i2c_i801 idma64 crc32_pclmul thunderbolt i2c_smbus nvme_core
> xhci_pci virt_dma xhci_pci_renesas video wmi pinctrl_tigerlake [    3.338514]
> CR2: 00000000fffedfdd [    3.338517] ---[ end trace 0000000000000000 ]---
> [    3.504965] RIP: 0010:gpiod_set_raw_value_commit+0x3d/0xf0
> [    3.504973] Code: 48 89 e5 41 55 44 0f b6 ee 41 54 53 48 8b 17 48 2b
> 82 70 03 00 00 4c 8b a2 68 03 00 00 48 c1 f8 03 48 0f af c1 66 90 48 89
> c6 <49> 8b 44 24 60 44 89 ea 4c 89 e7 ff d0 0f 1f 00 5b 41 5c 41 5d 5d
> [    3.504975] RSP: 0018:ffffaad780f6f620 EFLAGS: 00010a03 [    3.504978]
> RAX: 333330b6bdbad102 RBX: ffff9c8d4a5f6800 RCX:
> cccccccccccccccd
> [    3.504979] RDX: ffff9c8d4a5f6d40 RSI: 333330b6bdbad102 RDI:
> ffff9c8d4a5f6d40
> [    3.504980] RBP: ffffaad780f6f638 R08: 00000001018c3789 R09:
> 0000000000000000
> [    3.504982] R10: ffff9c8c4009ee40 R11: 0000000000000000 R12:
> 00000000fffedf7d
> [    3.504983] R13: 0000000000000000 R14: 0000000000000001 R15:
> 0000000000000001
> [    3.504984] FS:  00007f98d04de880(0000) GS:ffff9c90df700000(0000)
> knlGS:0000000000000000
> [    3.504986] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> [    3.504988] CR2: 00000000fffedfdd CR3: 000000010b680003 CR4:
> 0000000000770ee0
> [    3.504989] DR0: 0000000000000000 DR1: 0000000000000000 DR2:
> 0000000000000000
> [    3.504990] DR3: 0000000000000000 DR6: 00000000ffff07f0 DR7:
> 0000000000000400
> [    3.504992] PKRU: 55555554
> 
> Thanks,
> Stefan

Thanks for the logs.

Could you please confirm that your test case was passing with 
https://github.com/torvalds/linux/commit/303feb3cc06ac0665d0ee9c1414941200e60e8a3 patch
but it is failing with the current patch series ?  

Regarding the failure 
The logs suggest that we are trying to access an invalid pointer while 
calling the gpiod_set_value_cansleep( ) API.
This could be possible if the cs_num is corrupted and we are trying to 
access an invalid spi->cs_gpiod[ ]. 
To confirm the same could you please do the following changes in the 
code and re-test.

After applying this patch series, in drivers/spi/spi.c file replace the 
following code snippet in __spi_add_device( ) function definition.
if (ctlr->cs_gpiods) {
        for (idx = 0; idx < SPI_CS_CNT_MAX; idx++)
                spi_set_csgpiod(spi, idx, ctlr->cs_gpiods[spi_get_chipselect(spi, idx)]); 
}

with the below code snippet

if (ctlr->cs_gpiods) {
        for (idx = 0; idx < SPI_CS_CNT_MAX; idx++) {
                if (!(idx != 0 && !spi_get_chipselect(spi, idx))) {
		printk("%s( ) [%d] cs[%d] = [%d]\n", __func__, __LINE__, idx, spi_get_chipselect(spi, idx));
		spi_set_csgpiod(spi, idx, ctlr->cs_gpiods[spi_get_chipselect(spi, idx)]);
	}
        }
}

And at the start of  spi_set_cs( ) function in drivers/spi/spi.c file add 
the following print statements.

printk("%s( ) [%d] spi->cs_index_mask == [%d]\n", __func__, __LINE__, spi->cs_index_mask);
printk("%s( ) [%d] cs_num == [%d]\n", __func__, __LINE__, cs_num);

Thanks,
Amit
> 
> >> Thanks,
> >>
> >> Stefan
> >>
> >>>> Thanks,
> >>>> Stefan Binding
> >>>>
> >>>>> Signed-off-by: Amit Kumar Mahapatra <amit.kumar-
> >>>> mahapatra@xxxxxxx>
> >>>>> ---
> >>>>>    drivers/spi/spi.c       | 226
> >>>> ++++++++++++++++++++++++++++------------
> >>>>>    include/linux/spi/spi.h |  32 ++++--
> >>>>>    2 files changed, 183 insertions(+), 75 deletions(-)
> >>>>>
> >>>>> diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c index
> >>>>> 9036d7a50674..04d7322170c4 100644
> >>>>> --- a/drivers/spi/spi.c
> >>>>> +++ b/drivers/spi/spi.c
> >>>>> @@ -612,10 +612,24 @@ static int spi_dev_check(struct device *dev,
> >>>>> void *data)  {
> >>>>>    	struct spi_device *spi = to_spi_device(dev);
> >>>>>    	struct spi_device *new_spi = data;
> >>>>> +	int idx, nw_idx;
> >>>>>
> >>>>> -	if (spi->controller == new_spi->controller &&
> >>>>> -	    spi_get_chipselect(spi, 0) == spi_get_chipselect(new_spi,
> >>>> 0))
> >>>>> -		return -EBUSY;
> >>>>> +	if (spi->controller == new_spi->controller) {
> >>>>> +		for (idx = 0; idx < SPI_CS_CNT_MAX; idx++) {
> >>>>> +			for (nw_idx = 0; nw_idx < SPI_CS_CNT_MAX;
> >>>>> nw_idx++) {
> >>>>> +				if ((idx != 0 &&
> >>>> !spi_get_chipselect(spi,
> >>>>> idx)) ||
> >>>>> +				    (nw_idx != 0 &&
> >>>>> !spi_get_chipselect(spi, nw_idx))) {
> >>>>> +					continue;
> >>>>> +				} else if (spi_get_chipselect(spi,
> >>>> idx) ==
> >>>>> +				    spi_get_chipselect(new_spi,
> >>>> nw_idx))
> >>>>> {
> >>>>> +					dev_err(dev,
> >>>>> +						"chipselect %d
> already
> >>>>> in use\n",
> >>>>> +
> >>>>> 	spi_get_chipselect(new_spi, nw_idx));
> >>>>> +					return -EBUSY;
> >>>>> +				}
> >>>>> +			}
> >>>>> +		}
> >>>>> +	}
> >>>>>    	return 0;
> >>>>>    }
> >>>>>
> >>>>> @@ -629,7 +643,7 @@ static int __spi_add_device(struct spi_device
> >>>>> *spi)
> >>>>>    {
> >>>>>    	struct spi_controller *ctlr = spi->controller;
> >>>>>    	struct device *dev = ctlr->dev.parent;
> >>>>> -	int status;
> >>>>> +	int status, idx;
> >>>>>
> >>>>>    	/*
> >>>>>    	 * We need to make sure there's no other device with this
> @@
> >>>>> -638,8
> >>>>> +652,6 @@ static int __spi_add_device(struct spi_device
> >>>>> *spi)
> >>>>>    	 */
> >>>>>    	status = bus_for_each_dev(&spi_bus_type, NULL, spi,
> >>>> spi_dev_check);
> >>>>>    	if (status) {
> >>>>> -		dev_err(dev, "chipselect %d already in use\n",
> >>>>> -				spi_get_chipselect(spi, 0));
> >>>>>    		return status;
> >>>>>    	}
> >>>>>
> >>>>> @@ -649,8 +661,10 @@ static int __spi_add_device(struct spi_device
> >>>>> *spi)
> >>>>>    		return -ENODEV;
> >>>>>    	}
> >>>>>
> >>>>> -	if (ctlr->cs_gpiods)
> >>>>> -		spi_set_csgpiod(spi, 0, ctlr-
> >>>>>> cs_gpiods[spi_get_chipselect(spi, 0)]);
> >>>>> +	if (ctlr->cs_gpiods) {
> >>>>> +		for (idx = 0; idx < SPI_CS_CNT_MAX; idx++)
> >>>>> +			spi_set_csgpiod(spi, idx, ctlr-
> >>>>>> cs_gpiods[spi_get_chipselect(spi, idx)]);
> >>>>> +	}
> >>>>>
> >>>>>    	/*
> >>>>>    	 * Drivers may modify this initial i/o setup, but will @@
> >>>>> -690,13
> >>>>> +704,15 @@ int spi_add_device(struct spi_device *spi)  {
> >>>>>    	struct spi_controller *ctlr = spi->controller;
> >>>>>    	struct device *dev = ctlr->dev.parent;
> >>>>> -	int status;
> >>>>> +	int status, idx;
> >>>>>
> >>>>> -	/* Chipselects are numbered 0..max; validate. */
> >>>>> -	if (spi_get_chipselect(spi, 0) >= ctlr->num_chipselect) {
> >>>>> -		dev_err(dev, "cs%d >= max %d\n",
> >>>>> spi_get_chipselect(spi, 0),
> >>>>> -			ctlr->num_chipselect);
> >>>>> -		return -EINVAL;
> >>>>> +	for (idx = 0; idx < SPI_CS_CNT_MAX; idx++) {
> >>>>> +		/* Chipselects are numbered 0..max; validate. */
> >>>>> +		if (spi_get_chipselect(spi, idx) >=
> >>>> ctlr->num_chipselect) {
> >>>>> +			dev_err(dev, "cs%d >= max %d\n",
> >>>>> spi_get_chipselect(spi, idx),
> >>>>> +				ctlr->num_chipselect);
> >>>>> +			return -EINVAL;
> >>>>> +		}
> >>>>>    	}
> >>>>>
> >>>>>    	/* Set the bus ID string */
> >>>>> @@ -713,12 +729,15 @@ static int spi_add_device_locked(struct
> >>>>> spi_device *spi)  {
> >>>>>    	struct spi_controller *ctlr = spi->controller;
> >>>>>    	struct device *dev = ctlr->dev.parent;
> >>>>> +	int idx;
> >>>>>
> >>>>> -	/* Chipselects are numbered 0..max; validate. */
> >>>>> -	if (spi_get_chipselect(spi, 0) >= ctlr->num_chipselect) {
> >>>>> -		dev_err(dev, "cs%d >= max %d\n",
> >>>>> spi_get_chipselect(spi, 0),
> >>>>> -			ctlr->num_chipselect);
> >>>>> -		return -EINVAL;
> >>>>> +	for (idx = 0; idx < SPI_CS_CNT_MAX; idx++) {
> >>>>> +		/* Chipselects are numbered 0..max; validate. */
> >>>>> +		if (spi_get_chipselect(spi, idx) >=
> >>>> ctlr->num_chipselect) {
> >>>>> +			dev_err(dev, "cs%d >= max %d\n",
> >>>>> spi_get_chipselect(spi, idx),
> >>>>> +				ctlr->num_chipselect);
> >>>>> +			return -EINVAL;
> >>>>> +		}
> >>>>>    	}
> >>>>>
> >>>>>    	/* Set the bus ID string */
> >>>>> @@ -966,58 +985,118 @@ static void spi_res_release(struct
> >>>>> spi_controller *ctlr, struct spi_message *mes  static void
> >>>>> spi_set_cs(struct spi_device *spi, bool enable, bool
> >>>> force)
> >>>>>    {
> >>>>>    	bool activate = enable;
> >>>>> +	u32 cs_num = __ffs(spi->cs_index_mask);
> >>>>> +	int idx;
> >>>>>
> >>>>>    	/*
> >>>>> -	 * Avoid calling into the driver (or doing delays) if the chip
> >>>> select
> >>>>> -	 * isn't actually changing from the last time this was called.
> >>>>> +	 * In parallel mode all the chip selects are
> >>>> asserted/de-asserted
> >>>>> +	 * at once
> >>>>>    	 */
> >>>>> -	if (!force && ((enable && spi->controller->last_cs ==
> >>>>> spi_get_chipselect(spi, 0)) ||
> >>>>> -		       (!enable && spi->controller->last_cs !=
> >>>>> spi_get_chipselect(spi, 0))) &&
> >>>>> -	    (spi->controller->last_cs_mode_high == (spi->mode &
> >>>>> SPI_CS_HIGH)))
> >>>>> -		return;
> >>>>> -
> >>>>> -	trace_spi_set_cs(spi, activate);
> >>>>> -
> >>>>> -	spi->controller->last_cs = enable ? spi_get_chipselect(spi, 0)
> >>>> : -1;
> >>>>> -	spi->controller->last_cs_mode_high = spi->mode &
> >>>>> SPI_CS_HIGH;
> >>>>> -
> >>>>> -	if ((spi_get_csgpiod(spi, 0) ||
> >>>> !spi->controller->set_cs_timing)
> >>>>> && !activate)
> >>>>> -		spi_delay_exec(&spi->cs_hold, NULL);
> >>>>> -
> >>>>> -	if (spi->mode & SPI_CS_HIGH)
> >>>>> -		enable = !enable;
> >>>>> +	if ((spi->cs_index_mask & SPI_PARALLEL_CS_MASK) ==
> >>>>> SPI_PARALLEL_CS_MASK) {
> >>>>> +		spi->controller->last_cs_mode_high = spi->mode &
> >>>>> SPI_CS_HIGH;
> >>>>> +
> >>>>> +		if ((spi_get_csgpiod(spi, 0) || !spi->controller-
> >>>>>> set_cs_timing) && !activate)
> >>>>> +			spi_delay_exec(&spi->cs_hold, NULL);
> >>>>> +
> >>>>> +		if (spi->mode & SPI_CS_HIGH)
> >>>>> +			enable = !enable;
> >>>>> +
> >>>>> +		if (spi_get_csgpiod(spi, 0) && spi_get_csgpiod(spi,
> >>>> 1)) {
> >>>>> +			if (!(spi->mode & SPI_NO_CS)) {
> >>>>> +				/*
> >>>>> +				 * Historically ACPI has no means of
> >>>> the
> >>>>> GPIO polarity and
> >>>>> +				 * thus the SPISerialBus() resource
> >>>>> defines it on the per-chip
> >>>>> +				 * basis. In order to avoid a chain of
> >>>>> negations, the GPIO
> >>>>> +				 * polarity is considered being Active
> >>>>> High. Even for the cases
> >>>>> +				 * when _DSD() is involved (in the
> >>>>> updated versions of ACPI)
> >>>>> +				 * the GPIO CS polarity must be
> >>>> defined
> >>>>> Active High to avoid
> >>>>> +				 * ambiguity. That's why we use
> >>>> enable,
> >>>>> that takes SPI_CS_HIGH
> >>>>> +				 * into account.
> >>>>> +				 */
> >>>>> +				if (has_acpi_companion(&spi->dev)) {
> >>>>> +					for (idx = 0; idx <
> >>>>> SPI_CS_CNT_MAX; idx++)
> >>>>> +
> >>>>> 	gpiod_set_value_cansleep(spi_get_csgpiod(spi, idx),
> >>>>> +
> >>>>> !enable);
> >>>>> +				} else {
> >>>>> +					for (idx = 0; idx <
> >>>>> SPI_CS_CNT_MAX; idx++)
> >>>>> +						/* Polarity handled by
> >>>>> GPIO library */
> >>>>> +
> >>>>> 	gpiod_set_value_cansleep(spi_get_csgpiod(spi, idx),
> >>>>> +
> >>>>> activate);
> >>>>> +				}
> >>>>> +			}
> >>>>> +			/* Some SPI masters need both GPIO CS &
> >>>>> slave_select */
> >>>>> +			if ((spi->controller->flags &
> >>>>> SPI_MASTER_GPIO_SS) &&
> >>>>> +			    spi->controller->set_cs)
> >>>>> +				spi->controller->set_cs(spi, !enable);
> >>>>> +		} else if (spi->controller->set_cs) {
> >>>>> +			spi->controller->set_cs(spi, !enable);
> >>>>> +		}
> >>>>>
> >>>>> -	if (spi_get_csgpiod(spi, 0)) {
> >>>>> -		if (!(spi->mode & SPI_NO_CS)) {
> >>>>> -			/*
> >>>>> -			 * Historically ACPI has no means of the GPIO
> >>>>> polarity and
> >>>>> -			 * thus the SPISerialBus() resource defines it
> >>>> on
> >>>>> the per-chip
> >>>>> -			 * basis. In order to avoid a chain of
> >>>> negations,
> >>>>> the GPIO
> >>>>> -			 * polarity is considered being Active High.
> >>>> Even
> >>>>> for the cases
> >>>>> -			 * when _DSD() is involved (in the updated
> >>>>> versions of ACPI)
> >>>>> -			 * the GPIO CS polarity must be defined Active
> >>>>> High to avoid
> >>>>> -			 * ambiguity. That's why we use enable, that
> >>>>> takes SPI_CS_HIGH
> >>>>> -			 * into account.
> >>>>> -			 */
> >>>>> -			if (has_acpi_companion(&spi->dev))
> >>>>> -
> >>>>> 	gpiod_set_value_cansleep(spi_get_csgpiod(spi, 0), !enable);
> >>>>> +		if (spi_get_csgpiod(spi, 0) || spi_get_csgpiod(spi, 1)
> >>>> ||
> >>>>> +		    !spi->controller->set_cs_timing) {
> >>>>> +			if (activate)
> >>>>> +				spi_delay_exec(&spi->cs_setup,
> NULL);
> >>>>>    			else
> >>>>> -				/* Polarity handled by GPIO library */
> >>>>> -
> >>>>> 	gpiod_set_value_cansleep(spi_get_csgpiod(spi, 0), activate);
> >>>>> +				spi_delay_exec(&spi->cs_inactive,
> >>>>> NULL);
> >>>>>    		}
> >>>>> -		/* Some SPI masters need both GPIO CS & slave_select
> >>>>> */
> >>>>> -		if ((spi->controller->flags & SPI_MASTER_GPIO_SS) &&
> >>>>> -		    spi->controller->set_cs)
> >>>>> +	} else {
> >>>>> +		/*
> >>>>> +		 * Avoid calling into the driver (or doing delays) if
> >>>> the
> >>>>> chip select
> >>>>> +		 * isn't actually changing from the last time this was
> >>>>> called.
> >>>>> +		 */
> >>>>> +		if (!force && ((enable && spi->controller->last_cs ==
> >>>>> +				spi_get_chipselect(spi, cs_num)) ||
> >>>>> +				(!enable && spi->controller->last_cs
> >>>> !=
> >>>>> +				 spi_get_chipselect(spi, cs_num))) &&
> >>>>> +		    (spi->controller->last_cs_mode_high ==
> >>>>> +		     (spi->mode & SPI_CS_HIGH)))
> >>>>> +			return;
> >>>>> +
> >>>>> +		trace_spi_set_cs(spi, activate);
> >>>>> +
> >>>>> +		spi->controller->last_cs = enable ?
> >>>>> spi_get_chipselect(spi, cs_num) : -1;
> >>>>> +		spi->controller->last_cs_mode_high = spi->mode &
> >>>>> SPI_CS_HIGH;
> >>>>> +
> >>>>> +		if ((spi_get_csgpiod(spi, cs_num) || !spi->controller-
> >>>>>> set_cs_timing) && !activate)
> >>>>> +			spi_delay_exec(&spi->cs_hold, NULL);
> >>>>> +
> >>>>> +		if (spi->mode & SPI_CS_HIGH)
> >>>>> +			enable = !enable;
> >>>>> +
> >>>>> +		if (spi_get_csgpiod(spi, cs_num)) {
> >>>>> +			if (!(spi->mode & SPI_NO_CS)) {
> >>>>> +				/*
> >>>>> +				 * Historically ACPI has no means of
> >>>> the
> >>>>> GPIO polarity and
> >>>>> +				 * thus the SPISerialBus() resource
> >>>>> defines it on the per-chip
> >>>>> +				 * basis. In order to avoid a chain of
> >>>>> negations, the GPIO
> >>>>> +				 * polarity is considered being Active
> >>>>> High. Even for the cases
> >>>>> +				 * when _DSD() is involved (in the
> >>>>> updated versions of ACPI)
> >>>>> +				 * the GPIO CS polarity must be
> >>>> defined
> >>>>> Active High to avoid
> >>>>> +				 * ambiguity. That's why we use
> >>>> enable,
> >>>>> that takes SPI_CS_HIGH
> >>>>> +				 * into account.
> >>>>> +				 */
> >>>>> +				if (has_acpi_companion(&spi->dev))
> >>>>> +
> >>>>> 	gpiod_set_value_cansleep(spi_get_csgpiod(spi, cs_num),
> >>>>> +
> >>>>> !enable);
> >>>>> +				else
> >>>>> +					/* Polarity handled by GPIO
> >>>>> library */
> >>>>> +
> >>>>> 	gpiod_set_value_cansleep(spi_get_csgpiod(spi, cs_num),
> >>>>> +
> >>>>> activate);
> >>>>> +			}
> >>>>> +			/* Some SPI masters need both GPIO CS &
> >>>>> slave_select */
> >>>>> +			if ((spi->controller->flags &
> >>>>> SPI_MASTER_GPIO_SS) &&
> >>>>> +			    spi->controller->set_cs)
> >>>>> +				spi->controller->set_cs(spi, !enable);
> >>>>> +		} else if (spi->controller->set_cs) {
> >>>>>    			spi->controller->set_cs(spi, !enable);
> >>>>> -	} else if (spi->controller->set_cs) {
> >>>>> -		spi->controller->set_cs(spi, !enable);
> >>>>> -	}
> >>>>> +		}
> >>>>>
> >>>>> -	if (spi_get_csgpiod(spi, 0) ||
> >>>> !spi->controller->set_cs_timing) {
> >>>>> -		if (activate)
> >>>>> -			spi_delay_exec(&spi->cs_setup, NULL);
> >>>>> -		else
> >>>>> -			spi_delay_exec(&spi->cs_inactive, NULL);
> >>>>> +		if (spi_get_csgpiod(spi, cs_num) || !spi->controller-
> >>>>>> set_cs_timing) {
> >>>>> +			if (activate)
> >>>>> +				spi_delay_exec(&spi->cs_setup,
> NULL);
> >>>>> +			else
> >>>>> +				spi_delay_exec(&spi->cs_inactive,
> >>>>> NULL);
> >>>>> +		}
> >>>>>    	}
> >>>>>    }
> >>>>>
> >>>>> @@ -2246,8 +2325,8 @@ static void of_spi_parse_dt_cs_delay(struct
> >>>>> device_node *nc,  static int of_spi_parse_dt(struct spi_controller
> >>>>> *ctlr, struct
> >>>> spi_device
> >>>>> *spi,
> >>>>>    			   struct device_node *nc)
> >>>>>    {
> >>>>> -	u32 value;
> >>>>> -	int rc;
> >>>>> +	u32 value, cs[SPI_CS_CNT_MAX] = {0};
> >>>>> +	int rc, idx;
> >>>>>
> >>>>>    	/* Mode (clock phase/polarity/etc.) */
> >>>>>    	if (of_property_read_bool(nc, "spi-cpha")) @@ -2320,13
> >>>>> +2399,21
> >>>> @@
> >>>>> static int of_spi_parse_dt(struct spi_controller *ctlr, struct
> >>>>> spi_device *spi,
> >>>>>    	}
> >>>>>
> >>>>>    	/* Device address */
> >>>>> -	rc = of_property_read_u32(nc, "reg", &value);
> >>>>> -	if (rc) {
> >>>>> +	rc = of_property_read_variable_u32_array(nc, "reg", &cs[0],
> 1,
> >>>>> +						 SPI_CS_CNT_MAX);
> >>>>> +	if (rc < 0 || rc > ctlr->num_chipselect) {
> >>>>>    		dev_err(&ctlr->dev, "%pOF has no valid 'reg' property
> >>>> (%d)\n",
> >>>>>    			nc, rc);
> >>>>>    		return rc;
> >>>>> +	} else if ((of_property_read_bool(nc, "parallel-memories"))
> &&
> >>>>> +		   (!(ctlr->flags & SPI_CONTROLLER_MULTI_CS))) {
> >>>>> +		dev_err(&ctlr->dev, "SPI controller doesn't support
> >>>> multi
> >>>>> CS\n");
> >>>>> +		return -EINVAL;
> >>>>>    	}
> >>>>> -	spi_set_chipselect(spi, 0, value);
> >>>>> +	for (idx = 0; idx < rc; idx++)
> >>>>> +		spi_set_chipselect(spi, idx, cs[idx]);
> >>>>> +	/* By default set the spi->cs_index_mask as 1 */
> >>>>> +	spi->cs_index_mask = 0x01;
> >>>>>
> >>>>>    	/* Device speed */
> >>>>>    	if (!of_property_read_u32(nc, "spi-max-frequency", &value))
> @@
> >>>>> -3907,7 +3994,8 @@ static int __spi_validate(struct spi_device
> >>>>> *spi, struct spi_message *message)
> >>>>>    	 * cs_change is set for each transfer.
> >>>>>    	 */
> >>>>>    	if ((spi->mode & SPI_CS_WORD) && (!(ctlr->mode_bits &
> >>>>> SPI_CS_WORD) ||
> >>>>> -					  spi_get_csgpiod(spi, 0))) {
> >>>>> +					  spi_get_csgpiod(spi, 0) ||
> >>>>> +					  spi_get_csgpiod(spi, 1))) {
> >>>>>    		size_t maxsize;
> >>>>>    		int ret;
> >>>>>
> >>>>> diff --git a/include/linux/spi/spi.h b/include/linux/spi/spi.h
> >>>>> index 873ced6ae4ca..6453b246e0af 100644
> >>>>> --- a/include/linux/spi/spi.h
> >>>>> +++ b/include/linux/spi/spi.h
> >>>>> @@ -19,6 +19,11 @@
> >>>>>    #include <linux/acpi.h>
> >>>>>    #include <linux/u64_stats_sync.h>
> >>>>>
> >>>>> +/* Max no. of CS supported per spi device */ #define
> >>>>> +SPI_CS_CNT_MAX
> >>>>> +2
> >>>>> +
> >>>>> +/* chip select mask */
> >>>>> +#define SPI_PARALLEL_CS_MASK	(BIT(0) | BIT(1))
> >>>>>    struct dma_chan;
> >>>>>    struct software_node;
> >>>>>    struct ptp_system_timestamp;
> >>>>> @@ -166,6 +171,7 @@ extern void
> >>>>> spi_transfer_cs_change_delay_exec(struct spi_message *msg,
> >>>>>     *	deasserted. If @cs_change_delay is used from
> @spi_transfer,
> >>>>> then the
> >>>>>     *	two delays will be added up.
> >>>>>     * @pcpu_statistics: statistics for the spi_device
> >>>>> + * @cs_index_mask: Bit mask of the active chipselect(s) in the
> >>>>> chipselect array
> >>>>>     *
> >>>>>     * A @spi_device is used to interchange data between an SPI slave
> >>>>>     * (usually a discrete chip) and CPU memory.
> >>>>> @@ -181,7 +187,7 @@ struct spi_device {
> >>>>>    	struct spi_controller	*controller;
> >>>>>    	struct spi_controller	*master;	/* Compatibility layer
> >>>> */
> >>>>>    	u32			max_speed_hz;
> >>>>> -	u8			chip_select;
> >>>>> +	u8			chip_select[SPI_CS_CNT_MAX];
> >>>>>    	u8			bits_per_word;
> >>>>>    	bool			rt;
> >>>>>    #define SPI_NO_TX	BIT(31)		/* No transmit wire */
> >>>>> @@ -202,7 +208,7 @@ struct spi_device {
> >>>>>    	void			*controller_data;
> >>>>>    	char			modalias[SPI_NAME_SIZE];
> >>>>>    	const char		*driver_override;
> >>>>> -	struct gpio_desc	*cs_gpiod;	/* Chip select gpio
> >>>> desc
> >>>>> */
> >>>>> +	struct gpio_desc	*cs_gpiod[SPI_CS_CNT_MAX];	/*
> >>>> Chip
> >>>>> select gpio desc */
> >>>>>    	struct spi_delay	word_delay; /* Inter-word delay */
> >>>>>    	/* CS delays */
> >>>>>    	struct spi_delay	cs_setup;
> >>>>> @@ -212,6 +218,13 @@ struct spi_device {
> >>>>>    	/* The statistics */
> >>>>>    	struct spi_statistics __percpu	*pcpu_statistics;
> >>>>>
> >>>>> +	/* Bit mask of the chipselect(s) that the driver need to use
> >>>> from
> >>>>> +	 * the chipselect array.When the controller is capable to
> >>>> handle
> >>>>> +	 * multiple chip selects & memories are connected in parallel
> >>>>> +	 * then more than one bit need to be set in cs_index_mask.
> >>>>> +	 */
> >>>>> +	u32			cs_index_mask : SPI_CS_CNT_MAX;
> >>>>> +
> >>>>>    	/*
> >>>>>    	 * likely need more hooks for more protocol options affecting
> how
> >>>>>    	 * the controller talks to each chip, like:
> >>>>> @@ -268,22 +281,22 @@ static inline void *spi_get_drvdata(const
> >>>>> struct spi_device *spi)
> >>>>>
> >>>>>    static inline u8 spi_get_chipselect(const struct spi_device
> >>>>> *spi,
> >>>> u8 idx)
> >>>>>    {
> >>>>> -	return spi->chip_select;
> >>>>> +	return spi->chip_select[idx];
> >>>>>    }
> >>>>>
> >>>>>    static inline void spi_set_chipselect(struct spi_device *spi,
> >>>>> u8
> >>>> idx, u8
> >>>>> chipselect)
> >>>>>    {
> >>>>> -	spi->chip_select = chipselect;
> >>>>> +	spi->chip_select[idx] = chipselect;
> >>>>>    }
> >>>>>
> >>>>>    static inline struct gpio_desc *spi_get_csgpiod(const struct
> >>>> spi_device
> >>>>> *spi, u8 idx)
> >>>>>    {
> >>>>> -	return spi->cs_gpiod;
> >>>>> +	return spi->cs_gpiod[idx];
> >>>>>    }
> >>>>>
> >>>>>    static inline void spi_set_csgpiod(struct spi_device *spi, u8
> >>>>> idx,
> >>>> struct
> >>>>> gpio_desc *csgpiod)
> >>>>>    {
> >>>>> -	spi->cs_gpiod = csgpiod;
> >>>>> +	spi->cs_gpiod[idx] = csgpiod;
> >>>>>    }
> >>>>>
> >>>>>    /**
> >>>>> @@ -388,6 +401,8 @@ extern struct spi_device
> >>>>> *spi_new_ancillary_device(struct spi_device *spi, u8 ch
> >>>>>     * @bus_lock_spinlock: spinlock for SPI bus locking
> >>>>>     * @bus_lock_mutex: mutex for exclusion of multiple callers
> >>>>>     * @bus_lock_flag: indicates that the SPI bus is locked for
> >>>> exclusive use
> >>>>> + * @multi_cs_cap: indicates that the SPI Controller can
> >>>> assert/de-assert
> >>>>> + *	more than one chip select at once.
> >>>>>     * @setup: updates the device mode and clocking records used by a
> >>>>>     *	device's SPI controller; protocol code may call this.  This
> >>>>>     *	must fail if an unrecognized or unsupported mode is
> requested.
> >>>>> @@ -554,6 +569,11 @@ struct spi_controller {
> >>>>>    #define SPI_CONTROLLER_MUST_TX		BIT(4)	/* Requires tx
> >>>>> */
> >>>>>
> >>>>>    #define SPI_MASTER_GPIO_SS		BIT(5)	/* GPIO CS must
> >>>> select
> >>>>> slave */
> >>>>> +	/*
> >>>>> +	 * The spi-controller has multi chip select capability and can
> >>>>> +	 * assert/de-assert more than one chip select at once.
> >>>>> +	 */
> >>>>> +#define SPI_CONTROLLER_MULTI_CS		BIT(6)
> >>>>>
> >>>>>    	/* Flag indicating if the allocation of this struct is devres-
> >>>>> managed */
> >>>>>    	bool			devm_allocated;
> >>>>> --
> >>>>> 2.17.1