From 352a2d5bfc336d980af69cb0ed24f86d9026f377 Mon Sep 17 00:00:00 2001 From: Jon Hunter Date: Mon, 15 Apr 2013 13:06:54 -0500 Subject: gpio/omap: ensure gpio context is initialised Commit a2797be (gpio/omap: force restore if context loss is not detectable) broke gpio support for OMAP when booting with device-tree because a restore of the gpio context being performed without ever initialising the gpio context. In other words, the context restored was bad. This problem could also occur in the non device-tree case, however, it is much less likely because when booting without device-tree we can detect context loss via a platform specific API and so context restore is performed less often. Nevertheless we should ensure that the gpio context is initialised on the first pm-runtime resume for gpio banks that could lose their state regardless of whether we are booting with device-tree or not. The context loss count was being initialised on the first pm-runtime suspend following a resume, by populating the get_count_loss_count() function pointer after the first pm-runtime resume. To make the code more readable and logical, initialise the context loss count on the first pm-runtime resume if the context is not yet valid. Reported-by: Tony Lindgren Signed-off-by: Jon Hunter Acked-by: Santosh Shilimkar Reviewed-by: Kevin Hilman Tested-by: Tony Lindgren Signed-off-by: Linus Walleij --- drivers/gpio/gpio-omap.c | 48 +++++++++++++++++++++++++++++++++++++++++++++--- 1 file changed, 45 insertions(+), 3 deletions(-) (limited to 'drivers') diff --git a/drivers/gpio/gpio-omap.c b/drivers/gpio/gpio-omap.c index 2050891d9c65..d3f7d2db870f 100644 --- a/drivers/gpio/gpio-omap.c +++ b/drivers/gpio/gpio-omap.c @@ -69,6 +69,7 @@ struct gpio_bank { bool is_mpuio; bool dbck_flag; bool loses_context; + bool context_valid; int stride; u32 width; int context_loss_count; @@ -1128,6 +1129,10 @@ static int omap_gpio_probe(struct platform_device *pdev) bank->loses_context = true; } else { bank->loses_context = pdata->loses_context; + + if (bank->loses_context) + bank->get_context_loss_count = + pdata->get_context_loss_count; } @@ -1178,9 +1183,6 @@ static int omap_gpio_probe(struct platform_device *pdev) omap_gpio_chip_init(bank); omap_gpio_show_rev(bank); - if (bank->loses_context) - bank->get_context_loss_count = pdata->get_context_loss_count; - pm_runtime_put(bank->dev); list_add_tail(&bank->node, &omap_gpio_list); @@ -1259,6 +1261,8 @@ update_gpio_context_count: return 0; } +static void omap_gpio_init_context(struct gpio_bank *p); + static int omap_gpio_runtime_resume(struct device *dev) { struct platform_device *pdev = to_platform_device(dev); @@ -1268,6 +1272,20 @@ static int omap_gpio_runtime_resume(struct device *dev) int c; spin_lock_irqsave(&bank->lock, flags); + + /* + * On the first resume during the probe, the context has not + * been initialised and so initialise it now. Also initialise + * the context loss count. + */ + if (bank->loses_context && !bank->context_valid) { + omap_gpio_init_context(bank); + + if (bank->get_context_loss_count) + bank->context_loss_count = + bank->get_context_loss_count(bank->dev); + } + _gpio_dbck_enable(bank); /* @@ -1384,6 +1402,29 @@ void omap2_gpio_resume_after_idle(void) } #if defined(CONFIG_PM_RUNTIME) +static void omap_gpio_init_context(struct gpio_bank *p) +{ + struct omap_gpio_reg_offs *regs = p->regs; + void __iomem *base = p->base; + + p->context.ctrl = __raw_readl(base + regs->ctrl); + p->context.oe = __raw_readl(base + regs->direction); + p->context.wake_en = __raw_readl(base + regs->wkup_en); + p->context.leveldetect0 = __raw_readl(base + regs->leveldetect0); + p->context.leveldetect1 = __raw_readl(base + regs->leveldetect1); + p->context.risingdetect = __raw_readl(base + regs->risingdetect); + p->context.fallingdetect = __raw_readl(base + regs->fallingdetect); + p->context.irqenable1 = __raw_readl(base + regs->irqenable); + p->context.irqenable2 = __raw_readl(base + regs->irqenable2); + + if (regs->set_dataout && p->regs->clr_dataout) + p->context.dataout = __raw_readl(base + regs->set_dataout); + else + p->context.dataout = __raw_readl(base + regs->dataout); + + p->context_valid = true; +} + static void omap_gpio_restore_context(struct gpio_bank *bank) { __raw_writel(bank->context.wake_en, @@ -1421,6 +1462,7 @@ static void omap_gpio_restore_context(struct gpio_bank *bank) #else #define omap_gpio_runtime_suspend NULL #define omap_gpio_runtime_resume NULL +static void omap_gpio_init_context(struct gpio_bank *p) {} #endif static const struct dev_pm_ops gpio_pm_ops = { -- cgit v1.2.3