1. I am trying to support spidev device on my evk.
2. I have followed the instructions in the following link.
http://forums.freescale.com/t5/i-MX-Microprocessors/How-to-use-SPI-driver-when-I-use-i-mx28evk/m-p/6...
a. CONFIG_SPI_MXS in kernel menuconfig
b. adding te following to spi_board_info spi_board_info[] in mx28evk.c file:
static struct mxs_spi_platform_data mx28evk_spi_data =
{
.hw_pin_init = mx28evk_spi_pin_init,
.hw_pin_release = mx28evk_spi_pin_release,
};
#if defined(CONFIG_SPI_MXS) || defined(CONFIG_SPI_MXS_MODULE)
{
.modalias = "spidev",
.max_speed_hz = 2000000, // 2 MHz
.bus_num = 1,
.chip_select = 0,
.platform_data = &mx28evk_spi_data
},
c. adding the following declaration in mx28evk.h:
extern int mx28evk_spi_pin_init(void);
extern int mx28evk_spi_pin_release(void);
d. adding the implementation of these functions in mx28evk_pins.c:
static void mx28evk_release_pin_group(struct pin_desc *pins, unsigned count)
{
int i;
struct pin_desc *pin;
for(i = 0; i < count; i++)
{
pin = &pins[i];
if(pin->fun == PIN_GPIO)
gpio_free(MXS_PIN_TO_GPIO(pin->id));
else
mxs_release_pin(pin->id, pin->name);
}
}
int mx28evk_spi_pin_init(void)
{
#if defined(CONFIG_SPI_MXS) || defined(CONFIG_SPI_MXS_MODULE)
mx28evk_init_pin_group(mx28evk_spi_pins, ARRAY_SIZE(mx28evk_spi_pins));
#endif
return 0;
}
int mx28evk_spi_pin_release(void)
{
#if defined(CONFIG_SPI_MXS) || defined(CONFIG_SPI_MXS_MODULE)
mx28evk_release_pin_group(mx28evk_spi_pins, ARRAY_SIZE(mx28evk_spi_pins));
#endif
return 0;
}
e. when the system is loading the kernel I see in the debug terminal the following + /dev/spidev1.0 is created in the file system.
mxs-spi mxs-spi.0: Max possible speed 24000 = 24000000/2 kHz
mxs-spi mxs-spi.0: at 0x80014000 mapped to 0xF0014000, irq=84, bus 1, DMA ver_major 4
f. I have compiled the spidev_test: and tried to run it on target (noting is connected to J89/U49) see the results below:
# /home$ ./spidev_test -D /dev/spidev1.0
speed 50000 delay 0 bits 8 mode 0
spi mode: 0
bits per word: 8
max speed: 50000 Hz (50 KHz)
can't send spi message: Invalid argument
Aborted
I do not understand what is the origin of the problem. what argument is invalid ?
can someone direct me what else I need to check/todo software or hardware wise.
how can I enable debug messages for the spidev driver ?
CONFIG_SPI_DEBUG is not supported in this kernel.
Thanks,
Roy
