Hello,
I'm trying to communicate with a LCD module via SPI on my i.MX53 NOVSOM module(BSP 11.09, kernel 2.6.35), but I'm failing on two dfferent ways. First of all: All the IOMUX configurations was done on mx53_xxx.c for the ECSPI1 interface. In order to use the spidev interface, I use the following structure:
static struct mxc_spi_master mxcspi1_data = {
.maxchipselect = 4,
.spi_version = 23,
.chipselect_active = mx53_evk_gpio_spi_chipselect_active,
.chipselect_inactive = mx53_evk_gpio_spi_chipselect_inactive,
};
static struct spi_board_info spi1_board_info[] __initdata = {
{
/* the modalias must be the same as spi device driver name */
.modalias = "spidev", /* Name of spi_driver for this device */
.max_speed_hz = 20000000, /* max spi SCK clock speed in HZ */
.bus_num = 1, /* Framework bus number */
.chip_select = 0, /* Framework chip select. */
.mode = SPI_MODE_1,
}
};
After that, on ltib menuconfig, I enable the drivers that I'll need.
Problem 1:
When using mxc_spi and spidev modules, the inode is created on /dev, but when I try to write a byte and after read other three, I get this Oops:
root@freescale ~$ init_lcd /dev/spidev1.0
B0!!!
CSPI1: count=1 fifo_size=2048
CSPI Finish
RX_DATA0 = 0x0
data IN = 0x0
Unable to handle kernel NULL pointer dereference at virtual address 00000000
pgd = 80004000
[00000000] *pgd=00000000
Internal error: Oops: 17 [#1] PREEMPT
last sysfs file: /sys/kernel/uevent_seqnum
Modules linked in: spidev mxc_spi
CPU: 0 Not tainted (2.6.35.3-850-gbc67621-g74af6dc-dirty #190)
PC is at mxc_spi_buf_rx_u16+0x24/0x50 [mxc_spi]
LR is at mxc_spi_buf_rx_u16+0x18/0x50 [mxc_spi]
pc : [<7f000268>] lr : [<7f00025c>] psr: 40000013
sp : 954b3f20 ip : 968ba000 fp : 00000000
r10: 00000000 r9 : 00000000 r8 : 00000004
r7 : 00000000 r6 : 95489118 r5 : 00000000 r4 : 00000000
r3 : 954b3f2c r2 : 954b3f14 r1 : 7f001093 r0 : 7f0010a7
Flags: nZcv IRQs on FIQs on Mode SVC_32 ISA ARM Segment kernel
Control: 10c5387d Table: 853f0019 DAC: 00000017
Process mxc_spi.0 (pid: 1906, stack limit = 0x954b22e8)
Stack: (0x954b3f20 to 0x954b4000)
3f20: 95489118 954a9f1c 95489600 00000001 00000004 7f000828 954a9f1c 00000000
3f40: 95489118 954a9f10 954a9ef0 ffffffff 95489600 802513f4 804c1870 954b2000
3f60: 7f0001ac 9548912c 95259ea0 95259ea0 954b2000 95259ea8 80251270 954b3f94
3f80: 95489120 00000000 9548911c 80069bc0 95212000 00000000 95212000 8006d51c
3fa0: 954b3fa0 954b3fa0 00000000 9543fe10 954b3fd4 80069a4c 95259ea0 00000000
3fc0: 00000000 00000000 00000000 8006d1f8 00000000 00000000 954b3fd8 954b3fd8
3fe0: 00000000 9543fe10 8006d180 8002c9c8 00000013 8002c9c8 707e7021 707e7421
[<7f000268>] (mxc_spi_buf_rx_u16+0x24/0x50 [mxc_spi]) from [<7f000828>] (mxc_spi_poll_transfer+0x12c/0x1bc [mxc_spi])
[<7f000828>] (mxc_spi_poll_transfer+0x12c/0x1bc [mxc_spi]) from [<802513f4>] (bitbang_work+0x184/0x30c)
[<802513f4>] (bitbang_work+0x184/0x30c) from [<80069bc0>] (worker_thread+0x174/0x218)
[<80069bc0>] (worker_thread+0x174/0x218) from [<8006d1f8>] (kthread+0x78/0x80)
[<8006d1f8>] (kthread+0x78/0x80) from [<8002c9c8>] (kernel_thread_exit+0x0/0x8)
Code: eb4e16c7 e5965050 e59f0024 e1a04005 (e1d510b0)
---[ end trace 2d71ca80cc18c456 ]---
Problem 2:
If I try to use spi_imx instead of mxc_spi, the /dev entry isn't created!
Can somebody help me? I think that Problem 2 is easier to solve than 1, so anybody could give me a hint?
Best Regards,
Ricardo Gurgel
