Enabling spidev in MCSPI1

Enabling spidev in MCSPI1

[Philip Balister]

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I'm trying to enable spidev on mcspi1, but when I do, the kernel while 
booting after the kernel is uncompressed. No useful messages are 
displayed. This is with a current git.

I've attached the diff I use to add the spi driver to the board file. 
(OVero + Summit).

With the #if 0 inplace the kernel boots, enable that code and it fails.

+#if 0
+       spi_register_board_info(overo_mcspi_board_info,
+               ARRAY_SIZE(overo_mcspi_board_info));
+#endif

Does anyone see anything obviously wrong with what I am doing?

Philip

[-- Attachment #2: spidev.diff --]
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diff --git a/arch/arm/mach-omap2/board-overo.c b/arch/arm/mach-omap2/board-overo.c
index d192dd9..804d88f 100644
--- a/arch/arm/mach-omap2/board-overo.c
+++ b/arch/arm/mach-omap2/board-overo.c
@@ -33,6 +33,8 @@
 #include <linux/mtd/nand.h>
 #include <linux/mtd/partitions.h>
 
+#include <linux/spi/spi.h>
+
 #include <asm/mach-types.h>
 #include <asm/mach/arch.h>
 #include <asm/mach/flash.h>
@@ -184,6 +186,16 @@ static inline void __init overo_init_smsc911x(void)
 static inline void __init overo_init_smsc911x(void) { return; }
 #endif
 
+static struct spi_board_info overo_mcspi_board_info[] = {
+	{
+		.modalias	= "spidev",
+		.max_speed_hz	= 12000000, // 12 MHz
+		.bus_num	= 1,
+		.chip_select	= 0,
+		.mode		= SPI_MODE_1,
+	},
+};
+
 static struct mtd_partition overo_nand_partitions[] = {
 	{
 		.name           = "xloader",
@@ -424,7 +436,10 @@ static void __init overo_init(void)
 	usb_ehci_init(&ehci_pdata);
 	overo_ads7846_init();
 	overo_init_smsc911x();
-
+#if 0
+	spi_register_board_info(overo_mcspi_board_info,
+		ARRAY_SIZE(overo_mcspi_board_info));
+#endif
 	/* Ensure SDRC pins are mux'd for self-refresh */
 	omap_mux_init_signal("sdrc_cke0", OMAP_PIN_OUTPUT);
 	omap_mux_init_signal("sdrc_cke1", OMAP_PIN_OUTPUT);

Re: Enabling spidev in MCSPI1

[Hemanth V]

> I'm trying to enable spidev on mcspi1, but when I do, the kernel while
> booting after the kernel is uncompressed. No useful messages are
> displayed. This is with a current git.
>
> I've attached the diff I use to add the spi driver to the board file.
> (OVero + Summit).
>
> With the #if 0 inplace the kernel boots, enable that code and it fails.
>
> +#if 0
> +       spi_register_board_info(overo_mcspi_board_info,
> +               ARRAY_SIZE(overo_mcspi_board_info));
> +#endif
>
> Does anyone see anything obviously wrong with what I am doing?
>

Is SPI1 also used for touchscreen on your board, if so it might be conflicting

Re: Enabling spidev in MCSPI1

[Paul Walmsley]

Hi Philip,

On Wed, 13 Jan 2010, Philip Balister wrote:

> I'm trying to enable spidev on mcspi1, but when I do, the kernel while booting
> after the kernel is uncompressed. No useful messages are displayed. This is
> with a current git.
> 
> I've attached the diff I use to add the spi driver to the board file. (OVero +
> Summit).

Maybe try enabling early printk support if you haven't already?

http://www.mail-archive.com/linux-omap@vger.kernel.org/msg21017.html


- Paul

Re: Enabling spidev in MCSPI1

[Philip Balister]

On 01/13/2010 03:36 PM, Paul Walmsley wrote:
> Hi Philip,
>
> On Wed, 13 Jan 2010, Philip Balister wrote:
>
>> I'm trying to enable spidev on mcspi1, but when I do, the kernel while booting
>> after the kernel is uncompressed. No useful messages are displayed. This is
>> with a current git.
>>
>> I've attached the diff I use to add the spi driver to the board file. (OVero +
>> Summit).
>
> Maybe try enabling early printk support if you haven't already?
>
> http://www.mail-archive.com/linux-omap@vger.kernel.org/msg21017.html

I think the early printk stuff was stopping me seeing the message ....

Unfortunately, I found the conflicting driver, the 7846 touchscreen 
driver, and disabled it, so the kernel boots again. (Before I could boot 
with debugging messages enabled)

I suspect the kernel should not crash if two drivers try to claim the 
spi device. If someone is interested, I can reanable the bad 
configuration and try to collect better data.

Philip