Message ID | 1991832745.2612487.1345496141598.JavaMail.root@advansee.com |
---|---|
State | Accepted |
Commit | 5dafa4543c399d329c7b01df1afa98437861cac0 |
Delegated to: | Stefano Babic |
Headers | show |
On 20/08/2012 22:55, Benoît Thébaudeau wrote: > gpio_get_value() should use PSR like Linux, not DR, because DR does not always > reflect the pin state, while PSR does. This is especially useful to detect a > short circuit on a GPIO pin configured as output, or to read the level of a pin > controlled by a non-GPIO IOMUX function. > > Signed-off-by: Benoît Thébaudeau <benoit.thebaudeau@advansee.com> > Cc: Stefano Babic <sbabic@denx.de> > --- > This patch depends on http://patchwork.ozlabs.org/patch/178694/ . > > .../drivers/gpio/mxc_gpio.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git u-boot-imx-84ab1cb.orig/drivers/gpio/mxc_gpio.c u-boot-imx-84ab1cb/drivers/gpio/mxc_gpio.c > index 6615535..e9bf278 100644 > --- u-boot-imx-84ab1cb.orig/drivers/gpio/mxc_gpio.c > +++ u-boot-imx-84ab1cb/drivers/gpio/mxc_gpio.c > @@ -116,7 +116,7 @@ int gpio_get_value(unsigned gpio) > > regs = (struct gpio_regs *)gpio_ports[port]; > > - val = (readl(®s->gpio_dr) >> gpio) & 0x01; > + val = (readl(®s->gpio_psr) >> gpio) & 0x01; > > return val; > } > Kernel does the same. Acked-by: Stefano Babic <sbabic@denx.de> Best regards, Stefano Babic
On 20/08/2012 22:55, Benoît Thébaudeau wrote: > gpio_get_value() should use PSR like Linux, not DR, because DR does not always > reflect the pin state, while PSR does. This is especially useful to detect a > short circuit on a GPIO pin configured as output, or to read the level of a pin > controlled by a non-GPIO IOMUX function. > > Signed-off-by: Benoît Thébaudeau <benoit.thebaudeau@advansee.com> > Cc: Stefano Babic <sbabic@denx.de> > --- > This patch depends on http://patchwork.ozlabs.org/patch/178694/ . > > .../drivers/gpio/mxc_gpio.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git u-boot-imx-84ab1cb.orig/drivers/gpio/mxc_gpio.c u-boot-imx-84ab1cb/drivers/gpio/mxc_gpio.c > index 6615535..e9bf278 100644 > --- u-boot-imx-84ab1cb.orig/drivers/gpio/mxc_gpio.c > +++ u-boot-imx-84ab1cb/drivers/gpio/mxc_gpio.c > @@ -116,7 +116,7 @@ int gpio_get_value(unsigned gpio) > > regs = (struct gpio_regs *)gpio_ports[port]; > > - val = (readl(®s->gpio_dr) >> gpio) & 0x01; > + val = (readl(®s->gpio_psr) >> gpio) & 0x01; > > return val; > } > Applied to u-boot-imx, thanks. Best regards, Stefano Babic
diff --git u-boot-imx-84ab1cb.orig/drivers/gpio/mxc_gpio.c u-boot-imx-84ab1cb/drivers/gpio/mxc_gpio.c index 6615535..e9bf278 100644 --- u-boot-imx-84ab1cb.orig/drivers/gpio/mxc_gpio.c +++ u-boot-imx-84ab1cb/drivers/gpio/mxc_gpio.c @@ -116,7 +116,7 @@ int gpio_get_value(unsigned gpio) regs = (struct gpio_regs *)gpio_ports[port]; - val = (readl(®s->gpio_dr) >> gpio) & 0x01; + val = (readl(®s->gpio_psr) >> gpio) & 0x01; return val; }
gpio_get_value() should use PSR like Linux, not DR, because DR does not always reflect the pin state, while PSR does. This is especially useful to detect a short circuit on a GPIO pin configured as output, or to read the level of a pin controlled by a non-GPIO IOMUX function. Signed-off-by: Benoît Thébaudeau <benoit.thebaudeau@advansee.com> Cc: Stefano Babic <sbabic@denx.de> --- This patch depends on http://patchwork.ozlabs.org/patch/178694/ . .../drivers/gpio/mxc_gpio.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)