Re: [PATCH 2/2] McSPI Slave and DMA,FIFO support

["Hemanth V" <hemanthv@ti.com>]

----- Original Message ----- 
From: "Kevin Hilman" <khilman@deeprootsystems.com>
To: "Gadiyar, Anand" <gadiyar@ti.com>
Cc: "V, Hemanth" <hemanthv@ti.com>; <linux-omap@vger.kernel.org>
Sent: Wednesday, May 20, 2009 10:33 PM
Subject: Re: [PATCH 2/2] McSPI Slave and DMA,FIFO support


> "Gadiyar, Anand" <gadiyar@ti.com> writes:
>
>>> -----Original Message-----
>>> From: linux-omap-owner@vger.kernel.org
>>> [mailto:linux-omap-owner@vger.kernel.org] On Behalf Of Hemanth V
>>> Sent: Wednesday, May 20, 2009 11:27 AM
>>> To: linux-omap@vger.kernel.org
>>> Subject: [PATCH 2/2] McSPI Slave and DMA,FIFO support
>>>
>>> This patch adds MUX changes for SPI2 and also adds an
>>> option for test driver
>>>
>>> Signed-off-by: Hemanth V <hemanthv@ti.com>
>>> ---
>>>  arch/arm/mach-omap2/board-3430sdp.c   |   26 ++++++++++++++++++++++++++
>>>  arch/arm/mach-omap2/mux.c             |   11 +++++++++++
>>>  arch/arm/plat-omap/include/mach/mux.h |    7 +++++++
>>>  3 files changed, 44 insertions(+)
>>>
>>> Index: linux-omap-2.6/arch/arm/mach-omap2/board-3430sdp.c
>>> ===================================================================
>>> --- linux-omap-2.6.orig/arch/arm/mach-omap2/board-3430sdp.c 2009-05-20 
>>> 11:02:34.000000000 +0530
>>> +++ linux-omap-2.6/arch/arm/mach-omap2/board-3430sdp.c 2009-05-20 
>>> 11:05:22.000000000 +0530
>>> @@ -228,6 +228,13 @@
>>>  .single_channel = 1, /* 0: slave, 1: master */
>>>  };
>>>
>>> +#ifdef CONFIG_SPI_DEBUG
>>> +static struct omap2_mcspi_device_config dummy_mcspi_config = {
>>> + .turbo_mode = 0,
>>> + .single_channel = 1,  /* 0: slave, 1: master */
>>> +};
>>> +#endif
>>> +
>>>  static struct spi_board_info sdp3430_spi_board_info[] __initdata = {
>>>  [0] = {
>>>  /*
>>> @@ -242,6 +249,18 @@
>>>  .irq = 0,
>>>  .platform_data = &tsc2046_config,
>>>  },
>>> +#ifdef CONFIG_SPI_DEBUG
>>> + [1] = {
>>> + /* SPI test driver attached to SPI2 controller by
>>> + * default
>>> + */
>>> + .modalias = "spitst",
>>> + .bus_num = 2,
>>> + .chip_select = 0,
>>> + .max_speed_hz = 1500000,
>>> + .controller_data = &dummy_mcspi_config,
>>> + },
>>> +#endif
>>>  };
>>>
>>>  static struct platform_device sdp3430_lcd_device = {
>>> @@ -666,6 +685,13 @@
>>>
>>>  static void __init omap_3430sdp_init(void)
>>>  {
>>> +
>>> + /* SPI2 Pin MUX */
>>> + omap_cfg_reg(AA3_3430_McSPI2_CLK);
>>> + omap_cfg_reg(Y2_3430_McSPI2_SIMO);
>>> + omap_cfg_reg(Y3_3430_McSPI2_SOMI);
>>> + omap_cfg_reg(Y4_3430_McSPI2_CS0);
>>> +
>>
>> This will still change the padconf for this port unconditionally.
>>
>> How do we handle the case where the same platform (SDP in this case)
>> could have different configurations McSPI2 vs USBHOST2, etc? Is there
>> a clean way, or do we have no option but to use a CONFIG option?
>
> What about building both as modules and doing the muxing on module
> load with a warning if it's taking the pins away from antother
> feature.
>
> Longer term, we need a more dynamic way to request pins when there are
> conflicts like this.
>
> Kevin

Might be the easiest option right now is to remove omap_cfg_reg calls and 
allow
users to add it when required.

Hemanth
>
>
>