On Thu, Mar 18, 2010 at 06:11:00PM -0400, Ned Forrester wrote:
[...]
>
> I'm not familiar with spi_read and spi_write. I guess those may be part
> of the user space driver: spidev? (I wrote a dedicated protocol driver
> for my device.)
Looking at spi.c, spi_read and spi_write both use spi_syn
On 03/18/2010 06:11 PM, Ned Forrester wrote:
>
> It could be a lot of places, from bug in your code to bug in the
> controller driver. I'm not sure how much testing omap2_mcspi.c has
> received. When I first started using pxa2xx_spi.c, less than a year
> after it appeared in the kernel, I found a
On 03/18/2010 04:09 PM, Amit Uttamchandani wrote:
> On Thu, Mar 18, 2010 at 01:28:17PM -0400, Ned Forrester wrote:
>
> [...]
>
>>
>> The message is atomic in the sense that the controller driver guarantees
>> to complete all the transfers defined in the message (assuming no
>> errors) before it h
On Thu, Mar 18, 2010 at 01:28:17PM -0400, Ned Forrester wrote:
[...]
>
> The message is atomic in the sense that the controller driver guarantees
> to complete all the transfers defined in the message (assuming no
> errors) before it handles the next message. Each transfer may change
> the cloc
On 03/18/2010 12:46 PM, Amit Uttamchandani wrote:
> On Wed, Mar 17, 2010 at 05:28:16PM -0400, Ned Forrester wrote:
>
> [...]
>
>> If I recall correctly, the work queue does NOT run in interrupt context
>> (are allowed to sleep), and therefore mutexs are permitted (for locking
>> with other non-in
On Wed, Mar 17, 2010 at 05:28:16PM -0400, Ned Forrester wrote:
[...]
> If I recall correctly, the work queue does NOT run in interrupt context
> (are allowed to sleep), and therefore mutexs are permitted (for locking
> with other non-interrupt activity). The interrupt handler definitely
> runs i
On 03/17/2010 04:49 PM, Amit Uttamchandani wrote:
>
> I have modified 'drivers/net/ethoc.c' for spi communication and it is
> able to transmit/receive packets. However, I am confused about using
> spinlocks vs mutexes for locking access to the spi device.
>
> e.g. For the transmit function I use
I have modified 'drivers/net/ethoc.c' for spi communication and it is
able to transmit/receive packets. However, I am confused about using
spinlocks vs mutexes for locking access to the spi device.
e.g. For the transmit function I use a work_queue to schedule the
transmits. In the handler functio
