Re: [PATCH v3] gpio: twl4030: Cache the direction and output states in private data
On Thu, 10 Jan 2013 14:09:35 +0100, Peter Ujfalusi peter.ujfal...@ti.com wrote: Hi Linus, On 01/10/2013 11:41 AM, Linus Walleij wrote: On Thu, Dec 20, 2012 at 10:44 AM, Peter Ujfalusi peter.ujfal...@ti.com wrote: Use more coherent locking in the driver. Use bitfield to store the GPIO direction and if the pin is configured as output store the status also in a bitfiled. In this way we can just look at these bitfields when we need information about the pin status and only reach out to the chip when it is needed. Signed-off-by: Peter Ujfalusi peter.ujfal...@ti.com Acked-by: Linus Walleij linus.wall...@linaro.org --- Hi Grant, Changes sicne v2: - Fixed the mutex_unlock found by Michael. - Removed the debug prints addedd by v2 patch (remains from debugging) - Removed one blank line between includes and the first comment section. Sorry Peter this must have been missed somehow. This does not apply to the current v3.8-rc3, could you respin this on top of Torvalds' tree? Grant applied the patch which this one depends on: [1] https://patchwork.kernel.org/patch/1844511/ I had applied it, never pushed the tree out because I wasn't able to test my kernel tree for a couple of weeks due to travel. I saw the patch in Linus' tree and pulled it out of mine before I pushed it out. g. -- To unsubscribe from this list: send the line unsubscribe linux-omap in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: [PATCH v3] gpio: twl4030: Cache the direction and output states in private data
On Thu, Jan 10, 2013 at 2:09 PM, Peter Ujfalusi peter.ujfal...@ti.com wrote: On 01/10/2013 11:41 AM, Linus Walleij wrote: Sorry Peter this must have been missed somehow. This does not apply to the current v3.8-rc3, could you respin this on top of Torvalds' tree? Grant applied the patch which this one depends on: [1] https://patchwork.kernel.org/patch/1844511/ Hm, it is not in mainline, nor on Grant's merge or next branches so it must have fallen on the floor somehow. I applied both the patches not, thanks! Linus Walleij -- To unsubscribe from this list: send the line unsubscribe linux-omap in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: [PATCH v3] gpio: twl4030: Cache the direction and output states in private data
Hi Linus, On 01/17/2013 11:43 AM, Linus Walleij wrote: On Thu, Jan 10, 2013 at 2:09 PM, Peter Ujfalusi peter.ujfal...@ti.com wrote: On 01/10/2013 11:41 AM, Linus Walleij wrote: Sorry Peter this must have been missed somehow. This does not apply to the current v3.8-rc3, could you respin this on top of Torvalds' tree? Grant applied the patch which this one depends on: [1] https://patchwork.kernel.org/patch/1844511/ Hm, it is not in mainline, nor on Grant's merge or next branches so it must have fallen on the floor somehow. I applied both the patches not, thanks! Thank you, I was planning to go through my pending patches tomorrow and resend or annoy maintainers with them. Thanks again, Péter -- To unsubscribe from this list: send the line unsubscribe linux-omap in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: [PATCH v3] gpio: twl4030: Cache the direction and output states in private data
On Thu, Dec 20, 2012 at 10:44 AM, Peter Ujfalusi peter.ujfal...@ti.com wrote: Use more coherent locking in the driver. Use bitfield to store the GPIO direction and if the pin is configured as output store the status also in a bitfiled. In this way we can just look at these bitfields when we need information about the pin status and only reach out to the chip when it is needed. Signed-off-by: Peter Ujfalusi peter.ujfal...@ti.com Acked-by: Linus Walleij linus.wall...@linaro.org --- Hi Grant, Changes sicne v2: - Fixed the mutex_unlock found by Michael. - Removed the debug prints addedd by v2 patch (remains from debugging) - Removed one blank line between includes and the first comment section. Sorry Peter this must have been missed somehow. This does not apply to the current v3.8-rc3, could you respin this on top of Torvalds' tree? Yours, Linus Walleij -- To unsubscribe from this list: send the line unsubscribe linux-omap in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: [PATCH v3] gpio: twl4030: Cache the direction and output states in private data
Hi Linus, On 01/10/2013 11:41 AM, Linus Walleij wrote: On Thu, Dec 20, 2012 at 10:44 AM, Peter Ujfalusi peter.ujfal...@ti.com wrote: Use more coherent locking in the driver. Use bitfield to store the GPIO direction and if the pin is configured as output store the status also in a bitfiled. In this way we can just look at these bitfields when we need information about the pin status and only reach out to the chip when it is needed. Signed-off-by: Peter Ujfalusi peter.ujfal...@ti.com Acked-by: Linus Walleij linus.wall...@linaro.org --- Hi Grant, Changes sicne v2: - Fixed the mutex_unlock found by Michael. - Removed the debug prints addedd by v2 patch (remains from debugging) - Removed one blank line between includes and the first comment section. Sorry Peter this must have been missed somehow. This does not apply to the current v3.8-rc3, could you respin this on top of Torvalds' tree? Grant applied the patch which this one depends on: [1] https://patchwork.kernel.org/patch/1844511/ Not sure where. There were a third patch in v2 as well. I'm not sure about the status of that. [1] + this patch applies cleanly on top of mainline. Should I resend the series as v4 for your convenience? -- Péter -- To unsubscribe from this list: send the line unsubscribe linux-omap in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
[PATCH v3] gpio: twl4030: Cache the direction and output states in private data
Use more coherent locking in the driver. Use bitfield to store the GPIO
direction and if the pin is configured as output store the status also in a
bitfiled.
In this way we can just look at these bitfields when we need information
about the pin status and only reach out to the chip when it is needed.
Signed-off-by: Peter Ujfalusi peter.ujfal...@ti.com
Acked-by: Linus Walleij linus.wall...@linaro.org
---
Hi Grant,
Changes sicne v2:
- Fixed the mutex_unlock found by Michael.
- Removed the debug prints addedd by v2 patch (remains from debugging)
- Removed one blank line between includes and the first comment section.
Regards,
Peter
drivers/gpio/gpio-twl4030.c | 100
1 file changed, 65 insertions(+), 35 deletions(-)
diff --git a/drivers/gpio/gpio-twl4030.c b/drivers/gpio/gpio-twl4030.c
index 4643f9c..4d330e3 100644
--- a/drivers/gpio/gpio-twl4030.c
+++ b/drivers/gpio/gpio-twl4030.c
@@ -37,7 +37,6 @@
#include linux/i2c/twl.h
-
/*
* The GPIO subchip supports 18 GPIOs which can be configured as
* inputs or outputs, with pullups or pulldowns on each pin. Each
@@ -64,14 +63,15 @@
/* Mask for GPIO registers when aggregated into a 32-bit integer */
#define GPIO_32_MASK 0x0003
-/* Data structures */
-static DEFINE_MUTEX(gpio_lock);
-
struct gpio_twl4030_priv {
struct gpio_chip gpio_chip;
+ struct mutex mutex;
int irq_base;
+ /* Bitfields for state caching */
unsigned int usage_count;
+ unsigned int direction;
+ unsigned int out_state;
};
/*--*/
@@ -130,7 +130,7 @@ static inline int gpio_twl4030_read(u8 address)
/*--*/
-static u8 cached_leden;/* protected by gpio_lock */
+static u8 cached_leden;
/* The LED lines are open drain outputs ... a FET pulls to GND, so an
* external pullup is needed. We could also expose the integrated PWM
@@ -144,14 +144,12 @@ static void twl4030_led_set_value(int led, int value)
if (led)
mask = 1;
- mutex_lock(gpio_lock);
if (value)
cached_leden = ~mask;
else
cached_leden |= mask;
status = twl_i2c_write_u8(TWL4030_MODULE_LED, cached_leden,
TWL4030_LED_LEDEN_REG);
- mutex_unlock(gpio_lock);
}
static int twl4030_set_gpio_direction(int gpio, int is_input)
@@ -162,7 +160,6 @@ static int twl4030_set_gpio_direction(int gpio, int
is_input)
u8 base = REG_GPIODATADIR1 + d_bnk;
int ret = 0;
- mutex_lock(gpio_lock);
ret = gpio_twl4030_read(base);
if (ret = 0) {
if (is_input)
@@ -172,7 +169,6 @@ static int twl4030_set_gpio_direction(int gpio, int
is_input)
ret = gpio_twl4030_write(base, reg);
}
- mutex_unlock(gpio_lock);
return ret;
}
@@ -212,7 +208,7 @@ static int twl_request(struct gpio_chip *chip, unsigned
offset)
struct gpio_twl4030_priv *priv = to_gpio_twl4030(chip);
int status = 0;
- mutex_lock(gpio_lock);
+ mutex_lock(priv-mutex);
/* Support the two LED outputs as output-only GPIOs. */
if (offset = TWL4030_GPIO_MAX) {
@@ -271,7 +267,7 @@ done:
if (!status)
priv-usage_count |= BIT(offset);
- mutex_unlock(gpio_lock);
+ mutex_unlock(priv-mutex);
return status;
}
@@ -279,64 +275,96 @@ static void twl_free(struct gpio_chip *chip, unsigned
offset)
{
struct gpio_twl4030_priv *priv = to_gpio_twl4030(chip);
+ mutex_lock(priv-mutex);
if (offset = TWL4030_GPIO_MAX) {
twl4030_led_set_value(offset - TWL4030_GPIO_MAX, 1);
- return;
+ goto out;
}
- mutex_lock(gpio_lock);
-
priv-usage_count = ~BIT(offset);
/* on last use, switch off GPIO module */
if (!priv-usage_count)
gpio_twl4030_write(REG_GPIO_CTRL, 0x0);
- mutex_unlock(gpio_lock);
+out:
+ mutex_unlock(priv-mutex);
}
static int twl_direction_in(struct gpio_chip *chip, unsigned offset)
{
- return (offset TWL4030_GPIO_MAX)
- ? twl4030_set_gpio_direction(offset, 1)
- : -EINVAL;
+ struct gpio_twl4030_priv *priv = to_gpio_twl4030(chip);
+ int ret;
+
+ mutex_lock(priv-mutex);
+ if (offset TWL4030_GPIO_MAX)
+ ret = twl4030_set_gpio_direction(offset, 1);
+ else
+ ret = -EINVAL;
+
+ if (!ret)
+ priv-direction = ~BIT(offset);
+
+ mutex_unlock(priv-mutex);
+
+ return ret;
}
static int twl_get(struct gpio_chip *chip, unsigned offset)
{
struct gpio_twl4030_priv *priv = to_gpio_twl4030(chip);
+ int ret;
int status = 0;
- if (!(priv-usage_count
