Anton Vorontsov wrote:
On Tue, Aug 11, 2009 at 12:04:18PM +0300, Felix Radensky wrote:
On MPC8536 Rev 1.0 the status of GPIO pins configured
as output cannot be determined by reading GPDAT register.
Workaround by reading the status of input pins from GPDAT
and the status of output pins from a shadow register.
Signed-off-by: Felix Radensky <fe...@embedded-sol.com>
---
arch/powerpc/sysdev/mpc8xxx_gpio.c | 6 +++++-
1 files changed, 5 insertions(+), 1 deletions(-)
diff --git a/arch/powerpc/sysdev/mpc8xxx_gpio.c
b/arch/powerpc/sysdev/mpc8xxx_gpio.c
index 103eace..0b996f3 100644
--- a/arch/powerpc/sysdev/mpc8xxx_gpio.c
+++ b/arch/powerpc/sysdev/mpc8xxx_gpio.c
@@ -56,9 +56,13 @@ static void mpc8xxx_gpio_save_regs(struct of_mm_gpio_chip
*mm)
static int mpc8xxx_gpio_get(struct gpio_chip *gc, unsigned int gpio)
{
+ u32 val;
struct of_mm_gpio_chip *mm = to_of_mm_gpio_chip(gc);
+ struct mpc8xxx_gpio_chip *mpc8xxx_gc = to_mpc8xxx_gpio_chip(mm);
+
+ val = in_be32(mm->regs + GPIO_DAT) && ~in_be32(mm->regs + GPIO_DIR);
Are you sure about &&?
No, that's obviously a typo. Bitwise & intended.
Plus, this are two reads instead of just one. I think it'll be better
to implement mpc8536_gpio_get(), and then do
if (of_device_is_compatible(np, ... 8536-gpio-bank ...))
gc->get = mpc8536_gpio_get;
else
gc->get = mpc8xxx_gpio_get;
The reads are from 2 different registers, how do you propose to replace
them by a single read ?
I'll implement mpc8572_gpio_get(), suitable for both 8572 and 8536.
- return in_be32(mm->regs + GPIO_DAT) & mpc8xxx_gpio2mask(gpio);
+ return (val | mpc8xxx_gc->data) & mpc8xxx_gpio2mask(gpio);
}
static void mpc8xxx_gpio_set(struct gpio_chip *gc, unsigned int gpio, int val)
Thanks,
_______________________________________________
Linuxppc-dev mailing list
Linuxppc-dev@lists.ozlabs.org
https://lists.ozlabs.org/listinfo/linuxppc-dev
