mcp2515 can controller on spi2.0 interrupt gpio

[AzHofi]

Hi,
i almost managed it working.
The kernel module recognizes the device, I can set the speed, but I cannot hook it up to a gpio interrupt.

My setting in /boot/script.fex are:

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[spi_board0]
modalias="mcp2515"
max_speed_hz=16000000
bus_num=2
chip_select=0
mode=3
full_duplex=0
manual_cs=0
irq_gpio=28

...

[gpio_para]
...
gpio_pin_28=port:PH15<6><default><default><default>


I soldered the mcp2515 INT pin to a20 som evb GPIO3  pin23 which is

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LCD1_D15/AT D1 /KP_IN5/SMC_VP P /EINT15/CSI1_D15/PH15

In /proc/interrupts I see

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175: 0 0 gpio-sunxi mcp251x

In /sys/kernel/debug/gpio

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gpio-28 (                             ) in hi

Please explain somebody how can I manage to trigger the interrupt on falling edge?
I am completely confused and lost.
I spent weeks to solve this problem from my holiday.

Thanks in advance!

[AzHofi]

I finally hardcoded the gpio and the irq into the mcp251x.c kernel module and voilá, perfection. It runs flawlessly on 1 megabit.

[Spark]

I finally hardcoded the gpio and the irq into the mcp251x.c kernel module and voilá, perfection. It runs flawlessly on 1 megabit.

Hi AzHofi,

Do you mind to share the code or just the diff of mcp251x.c kernel module?

Thanks

[AzHofi]

Do you mind to share the code or just the diff of mcp251x.c kernel module?

Sure, here is it, simple like a slap:

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diff --git a/drivers/net/can/mcp251x.c b/drivers/net/can/mcp251x.c
index 9d60742..ecde5c1 100644
--- a/drivers/net/can/mcp251x.c
+++ b/drivers/net/can/mcp251x.c
@@ -68,6 +68,7 @@


#include <linux/io.h>
+#include <linux/gpio.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/netdevice.h>
@@ -937,7 +938,7 @@ static int mcp251x_open(struct net_device *net)
        priv->force_quit = 0;
        priv->tx_skb = NULL;
        priv->tx_len = 0;
-
+       spi->irq = gpio_to_irq(28);

[Spark]

Thanks man 

[morind79]

Hi AzHofi,

I am using the same mcp2515, it is using PI14 and SPI from UEXT2 on a A20-OLinuXino-MICRO board.
I changed fex file like this :

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[spi_board0]
modalias="mcp2515"
max_speed_hz=16000000
bus_num=2
chip_select=0
mode=3
full_duplex=0
manual_cs=0
irq_gpio=13

[gpio_para]
...
gpio_pin_13 = port:PI14<5><default><default><default>
...


I restarted board and have a look at /proc/interrupts but I cannot see anything from mcp251x :-(

I have recompiled kernel to support MCP2515 but still without success...

thank you for your help

Denis

[AzHofi]

Dear Denis,
I suggest what I did, hardcode the irq into the mcp251x kernel module and recompilate
the kernel.

Hi AzHofi,

I am using the same mcp2515, it is using PI14 and SPI from UEXT2 on a A20-OLinuXino-MICRO board.
I changed fex file like this :
...
I restarted board and have a look at /proc/interrupts but I cannot see anything from mcp251x :-(

I have recompiled kernel to support MCP2515 but still without success...