When booting with device-tree the function pointer for detecting context
loss is not populated. Ideally, the pm_runtime framework should be
enhanced to allow a means for reporting context/state loss and we could
avoid populating such function pointers altogether. In the interim until
a generic non-device specific solution is in place, force a restore of
the gpio bank when enabling the gpio controller.
Adds a new device-tree property for the OMAP GPIO controller to indicate
if the GPIO controller is located in a power-domain that never loses
power and hence will always maintain its logic state.
Signed-off-by: Jon Hunter <jon-hun...@ti.com>
---
.../devicetree/bindings/gpio/gpio-omap.txt | 7 ++++--
drivers/gpio/gpio-omap.c | 25 +++++++++++++-------
2 files changed, 22 insertions(+), 10 deletions(-)
diff --git a/Documentation/devicetree/bindings/gpio/gpio-omap.txt
b/Documentation/devicetree/bindings/gpio/gpio-omap.txt
index a56e3a5..8d95052 100644
--- a/Documentation/devicetree/bindings/gpio/gpio-omap.txt
+++ b/Documentation/devicetree/bindings/gpio/gpio-omap.txt
@@ -20,8 +20,11 @@ Required properties:
8 = active low level-sensitive.
OMAP specific properties:
-- ti,hwmods: Name of the hwmod associated to the GPIO:
- "gpio<X>", <X> being the 1-based instance number from the HW spec
+- ti,hwmods: Name of the hwmod associated to the GPIO:
+ "gpio<X>", <X> being the 1-based instance number
+ from the HW spec.
+- ti,gpio-always-on: Indicates if a GPIO bank is always powered and
+ so will never lose its logic state.
Example:
diff --git a/drivers/gpio/gpio-omap.c b/drivers/gpio/gpio-omap.c
index 685e850..0557529 100644
--- a/drivers/gpio/gpio-omap.c
+++ b/drivers/gpio/gpio-omap.c
@@ -1120,11 +1120,17 @@ static int omap_gpio_probe(struct platform_device *pdev)
bank->width = pdata->bank_width;
bank->is_mpuio = pdata->is_mpuio;
bank->non_wakeup_gpios = pdata->non_wakeup_gpios;
- bank->loses_context = pdata->loses_context;
bank->regs = pdata->regs;
#ifdef CONFIG_OF_GPIO
bank->chip.of_node = of_node_get(node);
#endif
+ if (node) {
+ if (!of_property_read_bool(node, "ti,gpio-always-on"))
+ bank->loses_context = true;
+ } else {
+ bank->loses_context = pdata->loses_context;
+ }
+
bank->domain = irq_domain_add_linear(node, bank->width,
&irq_domain_simple_ops, NULL);
@@ -1258,9 +1264,9 @@ static int omap_gpio_runtime_resume(struct device *dev)
{
struct platform_device *pdev = to_platform_device(dev);
struct gpio_bank *bank = platform_get_drvdata(pdev);
- int context_lost_cnt_after;
u32 l = 0, gen, gen0, gen1;
unsigned long flags;
+ int c;
spin_lock_irqsave(&bank->lock, flags);
_gpio_dbck_enable(bank);
@@ -1276,14 +1282,17 @@ static int omap_gpio_runtime_resume(struct device *dev)
__raw_writel(bank->context.risingdetect,
bank->base + bank->regs->risingdetect);
- if (bank->get_context_loss_count) {
- context_lost_cnt_after =
- bank->get_context_loss_count(bank->dev);
- if (context_lost_cnt_after != bank->context_loss_count) {
+ if (bank->loses_context) {
+ if (!bank->get_context_loss_count) {
omap_gpio_restore_context(bank);
} else {
- spin_unlock_irqrestore(&bank->lock, flags);
- return 0;
+ c = bank->get_context_loss_count(bank->dev);
+ if (c != bank->context_loss_count) {
+ omap_gpio_restore_context(bank);
+ } else {
+ spin_unlock_irqrestore(&bank->lock, flags);
+ return 0;
+ }
}
}
--
1.7.10.4
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