On 05/07/2012 11:14 AM, Timur Tabi wrote:

Scott,

As you know, the P1022 has this weird LBC/DIU muxing problem. I'd like to add support for the 'nand' command while the DIU is active. Looking at the NAND code, I see functions nand_get_device() and nand_release_device(). What is the idea behind these functions?

In U-Boot they don't do much. In Linux they handle locking

Would it make sense to do something like this:

static int __board_start_nand(void) { return 0; } int board_start_nand(void) __attribute__((weak, alias("__board_start_nand")));

static void __board_finish_nand(void) { } void board_finish_nand(void) __attribute__((weak, alias("__board_finish_nand")));

static int nand_get_device(struct nand_chip *chip, struct mtd_info *mtd, int new_state) { chip->state = new_state;

return board_start_nand(); }

static void nand_release_device(struct mtd_info *mtd) { struct nand_chip *chip = mtd->priv;

board_finish_nand();

/* De-select the NAND device */ chip->select_chip(mtd, -1); }

What's wrong with the existing select_chip interface?

And if something new is needed, please use the function pointer interface rather than weak symbols, and do it first in Linux.

-Scott