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

[Wolfgang Grandegger <wg@grandegger.com>]

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.