-----Original Message----- From: Valentin Longchamp [mailto:valentin.longchamp@keymile.com] Sent: 29 May 2012 14:03 To: Prafulla Wadaskar Cc: holger.brunck@keymile.com; u-boot@lists.denx.de Subject: Re: [PATCH 3/3] spi/kirkwood: add weak functions board_spi_claim/release_bus
On 05/24/2012 10:38 AM, Prafulla Wadaskar wrote:
-----Original Message----- From: Valentin Longchamp [mailto:valentin.longchamp@keymile.com] Sent: 16 May 2012 16:24 To: Prafulla Wadaskar; holger.brunck@keymile.com Cc: Valentin Longchamp; u-boot@lists.denx.de; Holger Brunck;
Prafulla
Wadaskar Subject: [PATCH 3/3] spi/kirkwood: add weak functions board_spi_claim/release_bus
This allows a final, board specific, step in the claim/relase_bus function for the SPI controller, which may be needed for some
hardware
designs.
NAK, this is not needed if earlier two patches in the patch series
are in place.
In our case, this is still needed. As I had already explained you in the previous discussion, even with the generic approach, our hardware design requires one access to an additional signal (a GPIO) to configure an external HW multiplexer which is present to electrically remove the Nand Flash device from the signals used by the SPI bus and put it back when the accesses are over.
That's why my first implementation was only relying on these weak functions.
Okay, got it, on your board, apart from MPPs, you need additional control.
BTW: if NF_CEn could have been used this additional GPIO would not have needed. But any ways we cannot change your h/w now :-) So in that case it makes sense to expose these weak functions.
Regards.. Prafulla . . .