Re: [PATCH RESEND 0/6 v10] gpio: Add block GPIO

From: Wolfgang Grandegger
Date: Mon Dec 17 2012 - 09:57:42 EST


On 12/17/2012 01:10 PM, Russell King - ARM Linux wrote:
> On Mon, Dec 17, 2012 at 12:51:32PM +0100, Wolfgang Grandegger wrote:
>> +static void at91_gpiolib_set_block(struct gpio_chip *chip, unsigned long mask, unsigned long val)
>> +{
>> + struct at91_gpio_chip *at91_gpio = to_at91_gpio_chip(chip);
>> + void __iomem *pio = at91_gpio->regbase;
>> + u32 set_bits = val & mask;
>> + u32 clr_bits = ~val & mask;
>> +
>> + /* GPIO outputs can only be set at once or cleared at once */
>> + if (set_bits)
>> + __raw_writel(set_bits, pio + PIO_SODR);
>> + if (clr_bits)
>> + __raw_writel(clr_bits, pio + PIO_CODR);
>> +}
>
> You obviously didn't see my email...

Well, I did read you mail but it was not obvious to me how to maintain
compatibility with the existing "set" method... at a first glance.
But the synchronous data output is important and it's even simpler than
I thought. The block-set callback can directly write to ODSR because
"at91_set_gpio_output()" already has set OWER. Will give that a try
later today.

Wolfgang.

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