* gpio: rdc321x: Question about rdc_gpio_direction_input implementation
@ 2014-04-11 3:28 Axel Lin
2014-04-11 4:53 ` Florian Fainelli
0 siblings, 1 reply; 3+ messages in thread
From: Axel Lin @ 2014-04-11 3:28 UTC (permalink / raw)
To: Florian Fainelli; +Cc: Linus Walleij, Alexandre Courbot, linux-gpio
Hi Florian,
Current implementation in rdc_gpio_direction_input() looks wrong to me
because calling rdc_gpio_config(chip, gpio, 1) actually set the gpio to
OUTPUT HIGH rather than set the direction to INPUT.
I cannot find the datasheet, I'm wondering if below diff works.
Any chance to test it? I can send a formal patch if it works.
diff --git a/drivers/gpio/gpio-rdc321x.c b/drivers/gpio/gpio-rdc321x.c
index 88577c3..ccef383 100644
--- a/drivers/gpio/gpio-rdc321x.c
+++ b/drivers/gpio/gpio-rdc321x.c
@@ -119,10 +119,29 @@ unlock:
return err;
}
-/* configure GPIO pin as input */
static int rdc_gpio_direction_input(struct gpio_chip *chip, unsigned
gpio)
{
- return rdc_gpio_config(chip, gpio, 1);
+ struct rdc321x_gpio *gpch;
+ int reg, err;
+ u32 val;
+
+ gpch = container_of(chip, struct rdc321x_gpio, chip);
+ reg = gpio < 32 ? gpch->reg1_ctrl_base : gpch->reg2_ctrl_base;
+
+ spin_lock(&gpch->lock);
+
+ err = pci_read_config_dword(gpch->sb_pdev, reg, &val);
+ if (err)
+ goto unlock;
+
+ val &= ~(1 << (gpio & 0x1f));
+
+ err = pci_write_config_dword(gpch->sb_pdev, reg, val);
+
+unlock:
+ spin_unlock(&gpch->lock);
+
+ return err;
}
/*
^ permalink raw reply related [flat|nested] 3+ messages in thread
* Re: gpio: rdc321x: Question about rdc_gpio_direction_input implementation
2014-04-11 3:28 gpio: rdc321x: Question about rdc_gpio_direction_input implementation Axel Lin
@ 2014-04-11 4:53 ` Florian Fainelli
2014-04-11 5:56 ` Axel Lin
0 siblings, 1 reply; 3+ messages in thread
From: Florian Fainelli @ 2014-04-11 4:53 UTC (permalink / raw)
To: Axel Lin; +Cc: Linus Walleij, Alexandre Courbot, linux-gpio
Hi Axel,
2014-04-10 20:28 GMT-07:00 Axel Lin <axel.lin@ingics.com>:
> Hi Florian,
> Current implementation in rdc_gpio_direction_input() looks wrong to me
> because calling rdc_gpio_config(chip, gpio, 1) actually set the gpio to
> OUTPUT HIGH rather than set the direction to INPUT.
>
> I cannot find the datasheet, I'm wondering if below diff works.
> Any chance to test it? I can send a formal patch if it works.
The datasheet is available here:
http://www.atekmicro.com/download/r8610/R8610-G.pdf
I do not have access to the hardware at this very moment, but I should
be able to give this a try. I do not think GPIO input was tested at
all, the GPIO LEDs and such were driven as active outputs.
>
> diff --git a/drivers/gpio/gpio-rdc321x.c b/drivers/gpio/gpio-rdc321x.c
> index 88577c3..ccef383 100644
> --- a/drivers/gpio/gpio-rdc321x.c
> +++ b/drivers/gpio/gpio-rdc321x.c
> @@ -119,10 +119,29 @@ unlock:
> return err;
> }
>
> -/* configure GPIO pin as input */
> static int rdc_gpio_direction_input(struct gpio_chip *chip, unsigned
> gpio)
> {
> - return rdc_gpio_config(chip, gpio, 1);
> + struct rdc321x_gpio *gpch;
> + int reg, err;
> + u32 val;
> +
> + gpch = container_of(chip, struct rdc321x_gpio, chip);
> + reg = gpio < 32 ? gpch->reg1_ctrl_base : gpch->reg2_ctrl_base;
> +
> + spin_lock(&gpch->lock);
> +
> + err = pci_read_config_dword(gpch->sb_pdev, reg, &val);
> + if (err)
> + goto unlock;
> +
> + val &= ~(1 << (gpio & 0x1f));
> +
> + err = pci_write_config_dword(gpch->sb_pdev, reg, val);
> +
> +unlock:
> + spin_unlock(&gpch->lock);
> +
> + return err;
> }
>
> /*
--
Florian
^ permalink raw reply [flat|nested] 3+ messages in thread
* Re: gpio: rdc321x: Question about rdc_gpio_direction_input implementation
2014-04-11 4:53 ` Florian Fainelli
@ 2014-04-11 5:56 ` Axel Lin
0 siblings, 0 replies; 3+ messages in thread
From: Axel Lin @ 2014-04-11 5:56 UTC (permalink / raw)
To: Florian Fainelli; +Cc: Linus Walleij, Alexandre Courbot, linux-gpio
2014-04-11 12:53 GMT+08:00 Florian Fainelli <florian@openwrt.org>:
> Hi Axel,
>
> 2014-04-10 20:28 GMT-07:00 Axel Lin <axel.lin@ingics.com>:
>> Hi Florian,
>> Current implementation in rdc_gpio_direction_input() looks wrong to me
>> because calling rdc_gpio_config(chip, gpio, 1) actually set the gpio to
>> OUTPUT HIGH rather than set the direction to INPUT.
>>
>> I cannot find the datasheet, I'm wondering if below diff works.
>> Any chance to test it? I can send a formal patch if it works.
>
> The datasheet is available here:
> http://www.atekmicro.com/download/r8610/R8610-G.pdf
>
> I do not have access to the hardware at this very moment, but I should
> be able to give this a try. I do not think GPIO input was tested at
> all, the GPIO LEDs and such were driven as active outputs.
>
Just check the datasheet and I got confused.
The bits in reg1_ctrl_base/reg2_ctrl_base register is to enable/disable GPIOx
function.
However, I cannot find the register to set gpio direction.
There is a note in 4.4 says
"Note 4: Programmed by the GPIO mode & dir. Register. ".
But I cannot find the GPIO mode & dir. Register.
Regards,
Axel
^ permalink raw reply [flat|nested] 3+ messages in thread
end of thread, other threads:[~2014-04-11 5:56 UTC | newest]
Thread overview: 3+ messages (download: mbox.gz / follow: Atom feed)
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2014-04-11 3:28 gpio: rdc321x: Question about rdc_gpio_direction_input implementation Axel Lin
2014-04-11 4:53 ` Florian Fainelli
2014-04-11 5:56 ` Axel Lin
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