From: Jon Hunter Date: Thu, 4 Apr 2013 20:16:15 +0000 (-0500) Subject: gpio/omap: force restore if context loss is not detectable X-Git-Url: http://drtracing.org/?a=commitdiff_plain;h=a2797be;p=deliverable%2Flinux.git gpio/omap: force restore if context loss is not detectable 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 Acked-by: Santosh Shilimkar Reviewed-by: Kevin Hilman Signed-off-by: Linus Walleij --- diff --git a/Documentation/devicetree/bindings/gpio/gpio-omap.txt b/Documentation/devicetree/bindings/gpio/gpio-omap.txt index bff51a2fee1e..1b524c0c79fe 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", being the 1-based instance number from the HW spec +- ti,hwmods: Name of the hwmod associated to the GPIO: + "gpio", 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 f46b600e5e56..bb1e54f168b4 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; + } } }