There exists a situation of the mediatek pinctrl driver that may return
wrong pin function value for the pinmux driver:
- All pin function arrays are defined without const
- Some pin function arrays contain all-zero value, e.g.:
static int mt7622_spi_funcs[] = { 0, 0, 0, 0, 0, 0, };
- These arrays will be put into .bss section during compilation
- .bss section has no "a" attribute and does not exist in the final binary
file after objcopy.
- FDT binary blob is appended to the u-boot binary, which occupies the
.bss section.
- During board_f stage, .bss has not been initialized, and contains the
data of FDT, which is not full-zero data.
- pinctrl driver is initialized in board_f stage, and it will get wrong
data if another driver is going to set default pinctrl.
Since pinmux information and soc data are only meant to be read-only, thus
should be declared as const. This will force all pinctrl data being put
into .rodata section. Since .rodata has "a" attribute, even the all-zero
data will be allocated and filled with correct value in to u-boot binary.
Signed-off-by: Weijie Gao <weijie.gao@mediatek.com>
This construct is quite long-winded. In earlier days it made some sense
since auto-allocation was a strange concept. But with driver model now
used pretty universally, we can shorten this to 'auto'. This reduces
verbosity and makes it easier to read.
Coincidentally it also ensures that every declaration is on one line,
thus making dtoc's job easier.
Signed-off-by: Simon Glass <sjg@chromium.org>
Due to the pinctrl hardware of MT7622 is difference from others
SoC which using the common part of mediatek pinctrl.
So we need to modify the common part of mediatek pinctrl.
Signed-off-by: Sam Shih <sam.shih@mediatek.com>
Reviewed-by: Ryder Lee <ryder.lee@mediatek.com>
