Tool/software: Linux
Hi
I am trying to enable spidev support on a board based on a BeagleBoneBlack.
I have inherited a project developed using SDK 8.00.00.00 (Linux/arm 3.14.26) that makes use of /dev/spidev2.0
I am in the process of porting this project to the newest TISDK and find that I am unable to see any spidev within /dev/.
I have enabled CONFIG_SPI_SPIDEV=y within my .config
I have copied the pinmux defintions from the original project:
spi1_pins: pinmux_spi1_pins {
pinctrl-single,pins = <
0x108 0x32
0x194 0x33
0x198 0x13
0x19c 0x13
>;
};
and confirmed that these agree with the schematics, datasheet and TRM (unsurprisingly as the old code worked!)
There are also the following nodes defined on spi1:
&spi1 {
status = "okay";
pinctrl-names = "default";
pinctrl-0 = <&spi1_pins>;
spidev@0 {
spi-max-frequency = <24000000>;
reg = <0>;
compatible = "linux, spidev";
};
spidev@1 {
spi-max-frequency = <24000000>;
reg = <1>;
compatible = "linux, spidev";
};
};
- the syntax here has changed from the original by adding the "linux" term in the compatible field
- I notice that if I leave this out I get errors in the kernel start up serial as follows
[ 1.032904] spidev spi2.0: buggy DT: spidev listed directly in DT [ 1.038679] ------------[ cut here ]------------ [ 1.042994] WARNING: CPU: 0 PID: 1 at drivers/spi/spidev.c:719 spidev_probe+0x1a0/0x1bc() [ 1.050598] Modules linked in: [ 1.053448] CPU: 0 PID: 1 Comm: swapper Not tainted 4.4.19-gdb0b54cdad #30 [ 1.059837] Hardware name: Generic AM33XX (Flattened Device Tree) [ 1.065535] [<c0015c94>] (unwind_backtrace) from [<c0012e80>] (show_stack+0x10/0x14) [ 1.072753] [<c0012e80>] (show_stack) from [<c00300cc>] (warn_slowpath_common+0x80/0xac) [ 1.080281] [<c00300cc>] (warn_slowpath_common) from [<c0030194>] (warn_slowpath_null+0x1c/0x) [ 1.088454] [<c0030194>] (warn_slowpath_null) from [<c040cfb0>] (spidev_probe+0x1a0/0x1bc) [ 1.096128] [<c040cfb0>] (spidev_probe) from [<c040a260>] (spi_drv_probe+0x7c/0xa8) [ 1.103252] [<c040a260>] (spi_drv_probe) from [<c03b5308>] (driver_probe_device+0x1fc/0x2f0) [ 1.111110] [<c03b5308>] (driver_probe_device) from [<c03b36d4>] (bus_for_each_drv+0x60/0x94) [ 1.119039] [<c03b36d4>] (bus_for_each_drv) from [<c03b5080>] (__device_attach+0xb0/0x114) [ 1.126711] [<c03b5080>] (__device_attach) from [<c03b4634>] (bus_probe_device+0x84/0x8c) [ 1.134317] [<c03b4634>] (bus_probe_device) from [<c03b291c>] (device_add+0x370/0x56c) [ 1.141682] [<c03b291c>] (device_add) from [<c040ab58>] (spi_add_device+0x9c/0x134) [ 1.148805] [<c040ab58>] (spi_add_device) from [<c040b01c>] (of_register_spi_device+0x224/0x2) [ 1.156973] [<c040b01c>] (of_register_spi_device) from [<c040c81c>] (spi_register_master+0x25) [ 1.165531] [<c040c81c>] (spi_register_master) from [<c040ca38>] (devm_spi_register_master+0x) [ 1.174104] [<c040ca38>] (devm_spi_register_master) from [<c040f94c>] (omap2_mcspi_probe+0x2c) [ 1.182680] [<c040f94c>] (omap2_mcspi_probe) from [<c03b6b6c>] (platform_drv_probe+0x4c/0xb0) [ 1.190607] [<c03b6b6c>] (platform_drv_probe) from [<c03b5308>] (driver_probe_device+0x1fc/0x) [ 1.198854] [<c03b5308>] (driver_probe_device) from [<c03b5488>] (__driver_attach+0x8c/0x90) [ 1.206686] [<c03b5488>] (__driver_attach) from [<c03b362c>] (bus_for_each_dev+0x68/0x9c) [ 1.214292] [<c03b362c>] (bus_for_each_dev) from [<c03b48e0>] (bus_add_driver+0x1a0/0x218) [ 1.221977] [<c03b48e0>] (bus_add_driver) from [<c03b5be0>] (driver_register+0x78/0xf8) [ 1.229420] [<c03b5be0>] (driver_register) from [<c000966c>] (do_one_initcall+0x90/0x1dc) [ 1.237036] [<c000966c>] (do_one_initcall) from [<c089bdc8>] (kernel_init_freeable+0x12c/0x1b) [ 1.245120] [<c089bdc8>] (kernel_init_freeable) from [<c0621b7c>] (kernel_init+0xc/0xec) [ 1.252648] [<c0621b7c>] (kernel_init) from [<c000f598>] (ret_from_fork+0x14/0x3c) [ 1.259724] ---[ end trace b4816ec3f58ddc0f ]--- [ 1.264822] spidev spi2.1: buggy DT: spidev listed directly in DT [ 1.270539] ------------[ cut here ]------------
which appears to be calling spidev_probe
my confusion is that if I modify the DTS to include the needed "linux" term I appear to never call spidev probe on boot (I ahve inserted serial strings to check the codeflow for entry here)
If I inspect the DTB for these nodes I see:
62672: spi@481a0000 {
62695: compatible = "ti,omap4-mcspi";
62738- #address-cells = <0x00000001>;
62781- #size-cells = <0x00000000>;
62821- reg = <0x481a0000 0x000001c1>;
62864- interrupts = <0x0000007d>;
62903: ti,spi-num-cs = <0x00000002>;
62945: ti,hwmods = "spi1";
62977- dmas = <0x0000002d 0x0000002b 0x00000000 0x00000003 0x72783000 0x00000005 0x00000003 0x756c7400 0x00000044 0x00000000 0x016e3600 0x00000000>;
63131- dma-names = "tx0", "rx0", "tx1", "rx1";
63183- status = "okay";
63212- pinctrl-names = "default";
63251- pinctrl-0 = <0x00000044>;
63289: spidev@0 {
63312: spi-max-frequency = <0x016e3600>;
63362- reg = <0x00000000>;
63398: compatible = "spidev";
63437- };
63452: spidev@1 {
63475: spi-max-frequency = <0x016e3600>;
63525- reg = <0x00000001>;
63561: compatible = "spidev";
63600- };
63615- };
If I enable verbose debug at the printk level the following strings that appear relevant appear at boot:
[ 14.126735] device class 'spidev': registering [ 14.130861] kobject: 'spidev' (ddbcb188): kobject_add_internal: parent: 'class', set: 'class' [ 14.138792] kobject: 'spidev' (ddbcb188): kobject_uevent_env [ 14.144045] kobject: 'spidev' (ddbcb188): fill_kobj_path: path = '/class/spidev' [ 14.150925] bus: 'spi': add driver spidev [ 14.154646] kobject: 'spidev' (ddbce800): kobject_add_internal: parent: 'drivers', set: 'drivers' [ 14.162915] kobject: 'spidev' (ddbce800): kobject_uevent_env [ 14.168185] kobject: 'spidev' (ddbce800): fill_kobj_path: path = '/bus/spi/drivers/spidev' <---snip---> [ 14.326125] bus: 'platform': driver_probe_device: matched device 481a0000.spi with driver omap2_mcspi [ 14.334678] bus: 'platform': really_probe: probing driver omap2_mcspi with device 481a0000.spi [ 14.342731] pinctrl core: add 1 pinctrl maps [ 14.346768] devices_kset: Moving 481a0000.spi to end of list [ 14.352057] omap_hwmod: spi1: enabling [ 14.355537] powerdomain: completed transition in 0 loops [ 14.360464] clockdomain: l4ls_clkdm: enabled [ 14.364421] omap_hwmod: spi1: enabling clocks [ 14.368462] omap_hwmod: spi1: _omap4_enable_module: 2 [ 14.373196] device: 'spi2': device_add [ 14.376697] kobject: 'spi_master' (ddbe0780): kobject_add_internal: parent: '481a0000.spi', set: '(null)' [ 14.385599] kobject: 'spi2' (ddbc5408): kobject_add_internal: parent: 'spi_master', set: 'devices' [ 14.394160] PM: Adding info for No Bus:spi2 [ 14.398065] kobject: 'spi2' (ddbc5408): kobject_uevent_env [ 14.403161] kobject: 'spi2' (ddbc5408): fill_kobj_path: path = '/devices/platform/ocp/481a0000.spi/spi_master/spi' [ 14.413090] device: 'spi2.0': device_add [ 14.416784] kobject: 'spi2.0' (ddbc5808): kobject_add_internal: parent: 'spi2', set: 'devices' [ 14.424820] bus: 'spi': add device spi2.0 [ 14.428762] PM: Adding info for spi:spi2.0 [ 14.432562] kobject: 'spi2.0' (ddbc5808): kobject_uevent_env [ 14.437839] kobject: 'spi2.0' (ddbc5808): fill_kobj_path: path = '/devices/platform/ocp/481a0000.spi/spi_master/s' [ 14.448386] device: 'spi2.1': device_add [ 14.452029] kobject: 'spi2.1' (ddbc5c08): kobject_add_internal: parent: 'spi2', set: 'devices' [ 14.460061] bus: 'spi': add device spi2.1 [ 14.464011] PM: Adding info for spi:spi2.1 [ 14.467833] kobject: 'spi2.1' (ddbc5c08): kobject_uevent_env [ 14.473090] kobject: 'spi2.1' (ddbc5c08): fill_kobj_path: path = '/devices/platform/ocp/481a0000.spi/spi_master/s' [ 14.483536] driver: 'omap2_mcspi': driver_bound: bound to device '481a0000.spi' [ 14.490337] bus: 'platform': really_probe: bound device 481a0000.spi to driver omap2_mcspi [ 14.498127] kobject: 'omap2_mcspi' (ddbce880): kobject_uevent_env [ 14.503788] kobject: 'omap2_mcspi' (ddbce880): fill_kobj_path: path = '/bus/platform/drivers/omap2_mcspi'
but again I cannot see anything attempting to call spidev_probe and the /dev/ entries I would expect never appear
I can find the entries under /sys/bus/spi/devices
lrwxrwxrwx 1 root root 0 Jan 1 00:12 spi1.0 -> ../../../devices/platform/ocp/48030000.spi/spi_master/spi1/spi1.0 lrwxrwxrwx 1 root root 0 Jan 1 00:12 spi2.0 -> ../../../devices/platform/ocp/481a0000.spi/spi_master/spi2/spi2.0 lrwxrwxrwx 1 root root 0 Jan 1 00:12 spi2.1 -> ../../../devices/platform/ocp/481a0000.spi/spi_master/spi2/spi2.1
any suggestions for where I can look next?
Thanks for the help.
All the best,
Richard
