Vybrid ProcessorsのトピックRe: SPI Driver on Linux Side

SPI Driver on Linux Side

bfac — Tue, 22 Oct 2013 16:25:56 GMT

Hello!

We would like to use the SPI interface from Linux side fro Vybrid inside the timesys Linux BSP.

The device we need to communicate with is a custom device, so we will use a custom made user-space driver to communicate over raw SPI (we already have that driver ready).

Our user-space driver is done such it communicated with /dev/spi -like interface, so it would be great to have a spi module that already creates that device structure.

BR,

Bruno

Re: SPI Driver on Linux Side

karina_valencia — Tue, 22 Oct 2013 21:27:47 GMT

timesyssupport can you review this case and provide follow up?

Re: SPI Driver on Linux Side

timesyssupport — Thu, 24 Oct 2013 18:27:26 GMT

Hello Bruno,

You will need to add a spidev entry to mvf_spi_board_info[] to the board definition file in your kernel, at arch/arm/mach-mvf/board-twr-vf700.c. You will also need to register the pin you are using as the chip select by adding it to mvf_vf600_spi_cs[] in this same file.

Thanks, and let me know if you have any questions.

Timesys Support

Re: SPI Driver on Linux Side

bfac — Wed, 30 Oct 2013 13:33:22 GMT

heldercs, can you provide feed back on this topic?

Re: SPI Driver on Linux Side

helderhdw — Tue, 05 Nov 2013 20:41:39 GMT

Hello,

I´m using phyCore-vybrid, and I made the suggested changes:

1) include "spidev" entry to mvf_spi_board_info[], at arch/arm/mach-mvf/board-pcm052.c

static struct spi_board_info mvf_spi_board_info[] __initdata = {

{

/* The modalias must be the same as spi device driver name */

.modalias = "spidev",

.max_speed_hz = 50000000,

.bus_num = 0,

.chip_select = 0,

.mode = SPI_MODE_0,

};

2) register the chip select static int pcm052_spi_cs[] = { 41,}

3) and in ipcm052_board_init function, I included "mvf_add_dspi(0, &pcm052_spi_data)", and "spi_device_init()"

and I compiled the dspi driver like a MODULE, and started as show below. But segfalt occurred:

----------------------------------------------

# modprobe spi_mvf_dspi

setup mode 0, 0 bits/w, 50000000 Hz max --> 0

Unable to handle kernel NULL pointer dereference at virtual address 00000000

pgd = 864d8000

[00000000] *pgd=864a4831, *pte=00000000, *ppte=00000000

Internal error: Oops: 17 [#1]

Modules linked in: spi_mvf_dspi(+)

CPU: 0 Not tainted (3.0.15-ts-armv7l #79)

PC is at setup+0x178/0x1b0 [spi_mvf_dspi]

LR is at __kmalloc+0xf8/0x168

pc : [<7f000e54>] lr : [<800be088>] psr: a0000013

sp : 864ebd68 ip : 00000000 fp : 00000000

r10: 8640a768 r9 : 860d5a08 r8 : 00000000

r7 : 00000000 r6 : 864a2200 r5 : 00000000 r4 : 864b79c0

r3 : 804b2230 r2 : 00000000 r1 : ffffffe0 r0 : 864b79c0

Flags: NzCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment user

Control: 10c53c7d Table: 864d8059 DAC: 00000015

Process modprobe (pid: 788, stack limit = 0x864ea2e8)

Stack: (0x864ebd68 to 0x864ec000)

bd60: 7f000cdc 864a2200 8040fda8 8042dbe4 00000000 80248084

bd80: 8040fda8 8040fda8 00000000 02faf080 00000000 8021d560 86023938 864a2200

bda0: 860d6248 860d5a08 00000000 80248340 00000000 864a2200 860d6248 00000000

bdc0: 00000000 80248444 860d6248 8640a600 804a70f0 802484f0 804a70e8 860d6240

bde0: 8640a600 802485c4 860d621c 8640a740 8640a600 7f000bb0 00000000 8640a740

be00: 860d5a08 804ed638 860d5a3c 7f0012a0 00000000 7f003000 864ea000 8021f184

be20: 8021f16c 8021e174 00000000 860d5a08 7f0012a0 860d5a3c 864ad600 8021e318

be40: 00000000 7f0012a0 8021e28c 8021d184 860230f8 860d45d0 7f0012a0 7f0012a0

be60: 804a2a60 8021db58 7f00125c 804b8ebc 7f0012a0 7f0012a0 7f0012dc 864a6180

be80: 00000001 0000001c 864ea000 8021e594 8021f1ac 7f0012dc 7f0012dc 864a6180

bea0: 00000001 0000001c 864ea000 7f00300c 804b2d60 8002d428 8048c1dc ffffffff

bec0: 00000000 8048c1dc 00000000 80066da4 00000000 864b7400 888ed000 7f0012dc

bee0: 7f0012dc 864a6180 00000001 0000001c 7f001324 00000024 0000038f 800757f0

bf00: 7f0012e8 00000000 00003401 00000000 80074378 000a65d0 888ef4d4 888eed94

bf20: 014405eb 8044ddd8 00000000 00000000 00000000 00000000 00000000 00000000

bf40: 888ed000 00003354 888eeffc 888eeead 888efbfc 864dd700 0000142c 0000162c

bf60: 00000000 00000000 0000001e 0000001f 00000016 00000013 00000011 00000000

bf80: 864a30c0 00003354 000a65d0 000a6718 00000080 80032d84 864ea000 00000000

bfa0: 000a65a8 80032c00 00003354 000a65d0 000a6738 00003354 000a65d0 000a6690

bfc0: 00003354 000a65d0 000a6718 00000080 00000000 000a6718 000a5a24 000a65a8

bfe0: 7eff3b50 7eff3b40 00022670 2ac5bb40 600f0010 000a6738 87ffe821 87ffec21

[<7f000e54>] (setup+0x178/0x1b0 [spi_mvf_dspi]) from [<80248084>] (spi_setup+0xcc/0x104)

[<80248084>] (spi_setup+0xcc/0x104) from [<80248340>] (spi_add_device+0x94/0x124)

[<80248340>] (spi_add_device+0x94/0x124) from [<80248444>] (spi_new_device+0x74/0xac)

[<80248444>] (spi_new_device+0x74/0xac) from [<802484f0>] (spi_match_master_to_boardinfo+0x24/0x44)

[<802484f0>] (spi_match_master_to_boardinfo+0x24/0x44) from [<802485c4>] (spi_register_master+0xb4/0x118)

[<802485c4>] (spi_register_master+0xb4/0x118) from [<7f000bb0>] (spi_mvf_probe+0x29c/0x3c0 [spi_mvf_dspi])

[<7f000bb0>] (spi_mvf_probe+0x29c/0x3c0 [spi_mvf_dspi]) from [<8021f184>] (platform_drv_probe+0x18/0x1c)

[<8021f184>] (platform_drv_probe+0x18/0x1c) from [<8021e174>] (driver_probe_device+0x8c/0x1a4)

[<8021e174>] (driver_probe_device+0x8c/0x1a4) from [<8021e318>] (__driver_attach+0x8c/0x90)

[<8021e318>] (__driver_attach+0x8c/0x90) from [<8021d184>] (bus_for_each_dev+0x44/0x8c)

[<8021d184>] (bus_for_each_dev+0x44/0x8c) from [<8021db58>] (bus_add_driver+0x17c/0x24c)

[<8021db58>] (bus_add_driver+0x17c/0x24c) from [<8021e594>] (driver_register+0x78/0x148)

[<8021e594>] (driver_register+0x78/0x148) from [<7f00300c>] (spi_mvf_init+0xc/0x18 [spi_mvf_dspi])

[<7f00300c>] (spi_mvf_init+0xc/0x18 [spi_mvf_dspi]) from [<8002d428>] (do_one_initcall+0x10c/0x170)

[<8002d428>] (do_one_initcall+0x10c/0x170) from [<800757f0>] (sys_init_module+0x3d0/0x1a7c)

[<800757f0>] (sys_init_module+0x3d0/0x1a7c) from [<80032c00>] (ret_fast_syscall+0x0/0x30)

Code: e30810d0 eb42f450 e2504000 0a000004 (e5d53000)

---[ end trace e5ca59d17e94b3ab ]---

Segmentation fault

--------------------------------------------------------------

thanks,

Francisco

Re: SPI Driver on Linux Side

karina_valencia — Tue, 05 Nov 2013 21:31:11 GMT

timesyssupport can you continue with the follow up on this case?

Re: SPI Driver on Linux Side

timesyssupport — Tue, 05 Nov 2013 22:28:22 GMT

Hello Francisco,

Would you be able to send us the entire source file so we can review?

Thank you,

Timesys Support

Re: SPI Driver on Linux Side

helderhdw — Thu, 07 Nov 2013 13:37:07 GMT

Hello,

I resolved the dpsi driver, and DSPI works. I´m using the DSPI0, like following code:

-----------------------------------------

/*DSPI0*/

MVF600_PAD41_PTB19__DSPI0_PCS0,

MVF600_PAD42_PTB20__DSPI0_SIN,

MVF600_PAD43_PTB21__DSPI0_SOUT,

MVF600_PAD44_PTB22__DSPI0_SCK,

static int pcm052_spi_cs[] = {

89,

};

static struct spi_mvf_chip at26df081a_chip_info = {

.mode = SPI_MODE_0,

.bits_per_word = 8,

.void_write_data = 0,

.dbr = 0,

.pbr = 0,

.br = 0,

.pcssck = 0,

.pasc = 0,

.pdt = 0,

.cssck = 0,

.asc = 0,

.dt = 0,

};

static const struct spi_mvf_master pcm052_qspi_data __initconst = {

.bus_num = 0,

.chipselect = pcm052_qspi_cs,

.num_chipselect = ARRAY_SIZE(pcm052_qspi_cs),

.cs_control = NULL,

};

static struct spi_board_info mvf_spi_board_info[] __initdata = {

{

// The modalias must be the same as spi device driver name

//.modalias = "m25p80",

.modalias = "spidev",

.max_speed_hz = 16000000,

.bus_num = 0,

.chip_select = 0,

//.platform_data = &at26df081a_platform_data,

.controller_data = &at26df081a_chip_info

};

static void spi_device_init(void)

{

spi_register_board_info(mvf_spi_board_info,

ARRAY_SIZE(mvf_spi_board_info));

}

==== in pcm052_board_init function

mvf_add_dspi(0, &pcm052_spi_data);

//mvf_add_qspi(0, &pcm052_qspi_data);

spi_device_init();

Re: SPI Driver on Linux Side

helderhdw — Thu, 07 Nov 2013 15:37:39 GMT

Hello,

Now I need the other help. I´m using the DSPI for chip 0 (DSPI0), like following code:

-----------------------------------------

/*DSPI0*/

MVF600_PAD41_PTB19__DSPI0_PCS0,

MVF600_PAD42_PTB20__DSPI0_SIN,

MVF600_PAD43_PTB21__DSPI0_SOUT,

MVF600_PAD44_PTB22__DSPI0_SCK,

static int pcm052_spi_cs[] = {

89,

};

static struct spi_mvf_chip at26df081a_chip_info = {

.mode = SPI_MODE_0,

.bits_per_word = 8,

.void_write_data = 0,

.dbr = 0,

.pbr = 0,

.br = 0,

.pcssck = 0,

.pasc = 0,

.pdt = 0,

.cssck = 0,

.asc = 0,

.dt = 0,

};

static const struct spi_mvf_master pcm052_qspi_data __initconst = {

.bus_num = 0,

.chipselect = pcm052_qspi_cs,

.num_chipselect = ARRAY_SIZE(pcm052_qspi_cs),

.cs_control = NULL,

};

static struct spi_board_info mvf_spi_board_info[] __initdata = {

{

// The modalias must be the same as spi device driver name

//.modalias = "m25p80",

.modalias = "spidev",

.max_speed_hz = 16000000,

.bus_num = 0,

.chip_select = 0,

//.platform_data = &at26df081a_platform_data,

.controller_data = &at26df081a_chip_info

};

static void spi_device_init(void)

{

spi_register_board_info(mvf_spi_board_info,

ARRAY_SIZE(mvf_spi_board_info));

}

==== in pcm052_board_init function

mvf_add_dspi(0, &pcm052_spi_data);

//mvf_add_qspi(0, &pcm052_qspi_data);

spi_device_init();

===== in board-pcm052.c

---------------

and I like to use the other SPI pins (DSPI3), as show above:

/*DSPI3*/

MVF600_PAD89_PTD10__DSPI3_PCS0,

MVF600_PAD90_PTD11__DSPI3_SIN,

MVF600_PAD91_PTD12__DSPI3_SOUT,

MVF600_PAD92_PTD13__DSPI3_SCK,

what procedure to change these SPI pins?

regards,

Francisco

Re: SPI Driver on Linux Side

karina_valencia — Thu, 07 Nov 2013 16:08:54 GMT

HI Francisco,

can you create a new discussion with the new question please?

Re: SPI Driver on Linux Side

helderhdw — Thu, 07 Nov 2013 16:35:09 GMT

Hi Karina,

I created the new discussion.. https://community.freescale.com/message/361319#361319

thanks,

Franicsco

Re: SPI Driver on Linux Side

karina_valencia — Thu, 07 Nov 2013 16:37:32 GMT

Perfect, thanks.

Re: SPI Driver on Linux Side

vpa — Fri, 08 Nov 2013 13:20:18 GMT

Hi,

I try to use DSPI0 too. I follow this thread and this about change spi port.

I work on TWR-VF65GS10, so i modify the board file as above but i can't determine the chip select value.

In board file, chip select value is 134 but how can i determine this number ?

Re: SPI Driver on Linux Side

timesyssupport — Fri, 08 Nov 2013 19:14:48 GMT

Hello Vincent,

The Linux kernel for the TWR-VF65GS10 has a working DSPI driver for DSPI0 - you should not need to change the chip select if you are using the reference hardware.

Regards,

Timesys Support

Re: SPI Driver on Linux Side

vpa — Sat, 09 Nov 2013 08:54:33 GMT

Yes, i understand that but if i want to change or add other DSPI, i need to know how to determine chip select.

Thanks for help.

Re: SPI Driver on Linux Side

timesyssupport — Mon, 11 Nov 2013 21:52:52 GMT

Hello Vincent,

The chip select value corresponds to a GPIO pin - you can refer to the schematic for your hardware to determine the correct GPIO pin.

Regards,

Timesys Support

Re: SPI Driver on Linux Side

vpa — Tue, 12 Nov 2013 11:09:05 GMT

Hello,

In datasheet i can see some informations which i can't understand or translate to a correct pin number.

For example :

SPI0_PCS0 : - 364 MAP BGA = C13

- 176 LQFP = 167

- Pin name = PTB19

This is the same information on the schematics, no matches between reference and pin number.

Thanks.