On Wednesday 08 August 2012, Linus Walleij wrote:

On Wed, Aug 8, 2012 at 3:39 AM, Tony Prisk [off-list ref] wrote:

quoted

Converted the existing arch-vt8500 gpio to a platform_device.
Added support for WM8505 and WM8650 GPIO controllers.

(...)

quoted

+++ b/drivers/gpio/gpio-vt8500.c

This driver looks very one-bit-per-gpio typed. Are you sure you cannot
just reuse drivers/gpio/gpio-generic.c? Make a compelling case please...

quoted

+struct vt8500_gpio_bank_regs {
+       int     en;
+       int     dir;
+       int     data_out;
+       int     data_in;

Why are all these members int? They should be u8 from reading your code.

quoted

+       int     ngpio;
+};

Not necessarily 8 bit, but definitely unsigned.

quoted

+static struct vt8500_gpio_data vt8500_data = {
+       .num_banks      = 7,
+       .banks  = {
+               VT8500_BANK(0x00, 0x20, 0x40, 0x60, 26),
+               VT8500_BANK(0x04, 0x24, 0x44, 0x64, 28),
+               VT8500_BANK(0x08, 0x28, 0x48, 0x68, 31),
+               VT8500_BANK(0x0C, 0x2C, 0x4C, 0x6C, 19),
+               VT8500_BANK(0x10, 0x30, 0x50, 0x70, 19),
+               VT8500_BANK(0x14, 0x34, 0x54, 0x74, 23),
+               VT8500_BANK(-1, 0x3C, 0x5C, 0x7C, 9),    /* external gpio */

What on earth are all those magic numbers?

I *guess* they're enabling some default GPIO settings etc.

No, they are the register offsets you quoted above, per bank. There
is no easy way to abstract these, and I suggested putting the
values into the source code rather than describing each bank
separately in the .dtsi file.

My feeling however is that the "vt8500_chip->regoff" is wrong, which
would mean only the first bank works. The code adds the same offsets
per bank once more that it sets in this bank table.

	Arnd