On 12/17/2012 12:37 PM, Wolfgang Grandegger wrote:
> Hi Roland,
>
> On 12/15/2012 12:49 AM, Roland Stigge wrote:
>> Hi Wolfgang,
>>
>> thank you for the patch!
>>
>> On 14/12/12 18:58, 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;
>>> +
>>> + __raw_writel(mask, pio + (val ? PIO_SODR : PIO_CODR));
>>> +}
>>> +
>>
>> Without having an AT91 available right now, I guess the hardware
>> interface of this GPIO chip is different from the GPIO block API. While
>> the hardware has clear and set registers, the val parameter of
>> at91_gpiolib_set_block() should be interpreted as the actual output
>> values. See lpc32xx_gpo_set_block() for an example for handling set and
>> clear registers like this: First, set_bits and clear_bits words are
>> calculated from mask and val parameters, and finally written to the
>> respective hardware registers.
>>
>> Note that one .set_block() can result in writing both the set and clear
>> registers of the hardware when val contains both 0s and 1s in
>> respectively masked positions.
>
> Oops, I obviously did not test GPIO block write. The patch below does
> work now. Feel free to add it to the next version of your series.
The patch lacks an important fix, sorry. Please consider the updated
patch below.
Wolfgang.
>From a1f93ddea9c6c9c6a80d7a02d3c8d9902823fe47 Mon Sep 17 00:00:00 2001
From: Wolfgang Grandegger <w...@grandegger.com>
Date: Mon, 3 Dec 2012 08:31:55 +0100
Subject: [PATCH 1/2] gpio: add GPIO block callback functions for AT91
Signed-off-by: Wolfgang Grandegger <w...@grandegger.com>
---
arch/arm/mach-at91/gpio.c | 28 ++++++++++++++++++++++++++++
1 file changed, 28 insertions(+)
diff --git a/arch/arm/mach-at91/gpio.c b/arch/arm/mach-at91/gpio.c
index be42cf0..77c6f91 100644
--- a/arch/arm/mach-at91/gpio.c
+++ b/arch/arm/mach-at91/gpio.c
@@ -48,7 +48,9 @@ struct at91_gpio_chip {
static void at91_gpiolib_dbg_show(struct seq_file *s, struct gpio_chip *chip);
static void at91_gpiolib_set(struct gpio_chip *chip, unsigned offset, int val);
+static void at91_gpiolib_set_block(struct gpio_chip *chip, unsigned long mask,
unsigned long val);
static int at91_gpiolib_get(struct gpio_chip *chip, unsigned offset);
+static unsigned long at91_gpiolib_get_block(struct gpio_chip *chip, unsigned
long mask);
static int at91_gpiolib_direction_output(struct gpio_chip *chip,
unsigned offset, int val);
static int at91_gpiolib_direction_input(struct gpio_chip *chip,
@@ -62,7 +64,9 @@ static int at91_gpiolib_to_irq(struct gpio_chip *chip,
unsigned offset);
.direction_input = at91_gpiolib_direction_input, \
.direction_output = at91_gpiolib_direction_output, \
.get = at91_gpiolib_get, \
+ .get_block = at91_gpiolib_get_block, \
.set = at91_gpiolib_set, \
+ .set_block = at91_gpiolib_set_block, \
.dbg_show = at91_gpiolib_dbg_show, \
.to_irq = at91_gpiolib_to_irq, \
.ngpio = nr_gpio, \
@@ -896,6 +900,16 @@ static int at91_gpiolib_get(struct gpio_chip *chip,
unsigned offset)
return (pdsr & mask) != 0;
}
+static unsigned long at91_gpiolib_get_block(struct gpio_chip *chip, unsigned
long mask)
+{
+ struct at91_gpio_chip *at91_gpio = to_at91_gpio_chip(chip);
+ void __iomem *pio = at91_gpio->regbase;
+ u32 pdsr;
+
+ pdsr = __raw_readl(pio + PIO_PDSR);
+ return pdsr & mask;
+}
+
static void at91_gpiolib_set(struct gpio_chip *chip, unsigned offset, int val)
{
struct at91_gpio_chip *at91_gpio = to_at91_gpio_chip(chip);
@@ -905,6 +919,20 @@ static void at91_gpiolib_set(struct gpio_chip *chip,
unsigned offset, int val)
__raw_writel(mask, pio + (val ? PIO_SODR : PIO_CODR));
}
+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);
+}
+
static void at91_gpiolib_dbg_show(struct seq_file *s, struct gpio_chip *chip)
{
int i;
--
1.7.9.5
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