[ 3.8.y.z extended stable ] Patch "gpio/omap: auto-setup a GPIO when used as an IRQ" has been added to staging queue
Kamal Mostafa
kamal at canonical.com
Wed Oct 9 20:51:24 UTC 2013
This is a note to let you know that I have just added a patch titled
gpio/omap: auto-setup a GPIO when used as an IRQ
to the linux-3.8.y-queue branch of the 3.8.y.z extended stable tree
which can be found at:
http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.8.y-queue
This patch is scheduled to be released in version 3.8.13.11.
If you, or anyone else, feels it should not be added to this tree, please
reply to this email.
For more information about the 3.8.y.z tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable
Thanks.
-Kamal
------
>From c87db239729da29833aed6954856755d56d3dddf Mon Sep 17 00:00:00 2001
From: Javier Martinez Canillas <javier.martinez at collabora.co.uk>
Date: Wed, 25 Sep 2013 02:36:54 +0200
Subject: gpio/omap: auto-setup a GPIO when used as an IRQ
commit fac7fa162a19100298d5d91359960037dc5bfca9 upstream.
The OMAP GPIO controller HW requires a pin to be configured in GPIO
input mode in order to operate as an interrupt input. Since drivers
should not be aware of whether an interrupt pin is also a GPIO or not,
the HW should be fully configured/enabled as an IRQ if a driver solely
uses IRQ APIs such as request_irq(), and never calls any GPIO-related
APIs. As such, add the missing HW setup to the OMAP GPIO controller's
irq_chip driver.
Since this bypasses the GPIO subsystem we have to ensure that another
driver won't be able to request the same GPIO pin that is used as an
IRQ and set its direction as output. Requesting the GPIO and setting
its direction as input is allowed though.
This fixes smsc911x ethernet support for tobi and igep OMAP3 boards
and OMAP4 SDP SPI based ethernet that use a GPIO as an interrupt line.
Acked-by: Stephen Warren <swarren at nvidia.com>
Tested-by: George Cherian <george.cherian at ti.com>
Tested-by: Aaro Koskinen <aaro.koskinen at iki.fi>
Tested-by: Lars Poeschel <poeschel at lemonage.de>
Reviewed-by: Kevin Hilman <khilman at linaro.org>
Tested-by: Kevin Hilman <khilman at linaro.org>
Acked-by: Santosh Shilimkar <santosh.shilimkar at ti.com>
Acked-by: Tony Lindgren <tony at atomide.com>
Signed-off-by: Javier Martinez Canillas <javier.martinez at collabora.co.uk>
Signed-off-by: Linus Walleij <linus.walleij at linaro.org>
Signed-off-by: Kamal Mostafa <kamal at canonical.com>
---
drivers/gpio/gpio-omap.c | 129 ++++++++++++++++++++++++++++++-----------------
1 file changed, 83 insertions(+), 46 deletions(-)
diff --git a/drivers/gpio/gpio-omap.c b/drivers/gpio/gpio-omap.c
index 343fc2f..fea4c50 100644
--- a/drivers/gpio/gpio-omap.c
+++ b/drivers/gpio/gpio-omap.c
@@ -418,6 +418,52 @@ static int _set_gpio_triggering(struct gpio_bank *bank, int gpio,
return 0;
}
+static void _enable_gpio_module(struct gpio_bank *bank, unsigned offset)
+{
+ if (bank->regs->pinctrl) {
+ void __iomem *reg = bank->base + bank->regs->pinctrl;
+
+ /* Claim the pin for MPU */
+ __raw_writel(__raw_readl(reg) | (1 << offset), reg);
+ }
+
+ if (bank->regs->ctrl && !BANK_USED(bank)) {
+ void __iomem *reg = bank->base + bank->regs->ctrl;
+ u32 ctrl;
+
+ ctrl = __raw_readl(reg);
+ /* Module is enabled, clocks are not gated */
+ ctrl &= ~GPIO_MOD_CTRL_BIT;
+ __raw_writel(ctrl, reg);
+ bank->context.ctrl = ctrl;
+ }
+}
+
+static void _disable_gpio_module(struct gpio_bank *bank, unsigned offset)
+{
+ void __iomem *base = bank->base;
+
+ if (bank->regs->wkup_en &&
+ !LINE_USED(bank->mod_usage, offset) &&
+ !LINE_USED(bank->irq_usage, offset)) {
+ /* Disable wake-up during idle for dynamic tick */
+ _gpio_rmw(base, bank->regs->wkup_en, 1 << offset, 0);
+ bank->context.wake_en =
+ __raw_readl(bank->base + bank->regs->wkup_en);
+ }
+
+ if (bank->regs->ctrl && !BANK_USED(bank)) {
+ void __iomem *reg = bank->base + bank->regs->ctrl;
+ u32 ctrl;
+
+ ctrl = __raw_readl(reg);
+ /* Module is disabled, clocks are gated */
+ ctrl |= GPIO_MOD_CTRL_BIT;
+ __raw_writel(ctrl, reg);
+ bank->context.ctrl = ctrl;
+ }
+}
+
static int gpio_is_input(struct gpio_bank *bank, int mask)
{
void __iomem *reg = bank->base + bank->regs->direction;
@@ -431,9 +477,10 @@ static int gpio_irq_type(struct irq_data *d, unsigned type)
unsigned gpio = 0;
int retval;
unsigned long flags;
+ unsigned offset;
- if (WARN_ON(!BANK_USED(bank)))
- return -EINVAL;
+ if (!BANK_USED(bank))
+ pm_runtime_get_sync(bank->dev);
#ifdef CONFIG_ARCH_OMAP1
if (d->irq > IH_MPUIO_BASE)
@@ -451,7 +498,16 @@ static int gpio_irq_type(struct irq_data *d, unsigned type)
return -EINVAL;
spin_lock_irqsave(&bank->lock, flags);
- retval = _set_gpio_triggering(bank, GPIO_INDEX(bank, gpio), type);
+ offset = GPIO_INDEX(bank, gpio);
+ retval = _set_gpio_triggering(bank, offset, type);
+ if (!LINE_USED(bank->mod_usage, offset)) {
+ _enable_gpio_module(bank, offset);
+ _set_gpio_direction(bank, offset, 1);
+ } else if (!gpio_is_input(bank, 1 << offset)) {
+ spin_unlock_irqrestore(&bank->lock, flags);
+ return -EINVAL;
+ }
+
bank->irq_usage |= 1 << GPIO_INDEX(bank, gpio);
spin_unlock_irqrestore(&bank->lock, flags);
@@ -614,30 +670,14 @@ static int omap_gpio_request(struct gpio_chip *chip, unsigned offset)
spin_lock_irqsave(&bank->lock, flags);
/* Set trigger to none. You need to enable the desired trigger with
- * request_irq() or set_irq_type().
+ * request_irq() or set_irq_type(). Only do this if the IRQ line has
+ * not already been requested.
*/
- _set_gpio_triggering(bank, offset, IRQ_TYPE_NONE);
-
- if (bank->regs->pinctrl) {
- void __iomem *reg = bank->base + bank->regs->pinctrl;
-
- /* Claim the pin for MPU */
- __raw_writel(__raw_readl(reg) | (1 << offset), reg);
+ if (!LINE_USED(bank->irq_usage, offset)) {
+ _set_gpio_triggering(bank, offset, IRQ_TYPE_NONE);
+ _enable_gpio_module(bank, offset);
}
-
- if (bank->regs->ctrl && !BANK_USED(bank)) {
- void __iomem *reg = bank->base + bank->regs->ctrl;
- u32 ctrl;
-
- ctrl = __raw_readl(reg);
- /* Module is enabled, clocks are not gated */
- ctrl &= ~GPIO_MOD_CTRL_BIT;
- __raw_writel(ctrl, reg);
- bank->context.ctrl = ctrl;
- }
-
bank->mod_usage |= 1 << offset;
-
spin_unlock_irqrestore(&bank->lock, flags);
return 0;
@@ -646,31 +686,11 @@ static int omap_gpio_request(struct gpio_chip *chip, unsigned offset)
static void omap_gpio_free(struct gpio_chip *chip, unsigned offset)
{
struct gpio_bank *bank = container_of(chip, struct gpio_bank, chip);
- void __iomem *base = bank->base;
unsigned long flags;
spin_lock_irqsave(&bank->lock, flags);
-
- if (bank->regs->wkup_en) {
- /* Disable wake-up during idle for dynamic tick */
- _gpio_rmw(base, bank->regs->wkup_en, 1 << offset, 0);
- bank->context.wake_en =
- __raw_readl(bank->base + bank->regs->wkup_en);
- }
-
bank->mod_usage &= ~(1 << offset);
-
- if (bank->regs->ctrl && !BANK_USED(bank)) {
- void __iomem *reg = bank->base + bank->regs->ctrl;
- u32 ctrl;
-
- ctrl = __raw_readl(reg);
- /* Module is disabled, clocks are gated */
- ctrl |= GPIO_MOD_CTRL_BIT;
- __raw_writel(ctrl, reg);
- bank->context.ctrl = ctrl;
- }
-
+ _disable_gpio_module(bank, offset);
_reset_gpio(bank, bank->chip.base + offset);
spin_unlock_irqrestore(&bank->lock, flags);
@@ -777,8 +797,16 @@ static void gpio_irq_shutdown(struct irq_data *d)
spin_lock_irqsave(&bank->lock, flags);
bank->irq_usage &= ~(1 << offset);
+ _disable_gpio_module(bank, offset);
_reset_gpio(bank, gpio);
spin_unlock_irqrestore(&bank->lock, flags);
+
+ /*
+ * If this is the last IRQ to be freed in the bank,
+ * disable the bank module.
+ */
+ if (!BANK_USED(bank))
+ pm_runtime_put(bank->dev);
}
static void gpio_ack_irq(struct irq_data *d)
@@ -928,13 +956,22 @@ static int gpio_output(struct gpio_chip *chip, unsigned offset, int value)
{
struct gpio_bank *bank;
unsigned long flags;
+ int retval = 0;
bank = container_of(chip, struct gpio_bank, chip);
spin_lock_irqsave(&bank->lock, flags);
+
+ if (LINE_USED(bank->irq_usage, offset)) {
+ retval = -EINVAL;
+ goto exit;
+ }
+
bank->set_dataout(bank, offset, value);
_set_gpio_direction(bank, offset, 0);
+
+exit:
spin_unlock_irqrestore(&bank->lock, flags);
- return 0;
+ return retval;
}
static int gpio_debounce(struct gpio_chip *chip, unsigned offset,
--
1.8.1.2
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