Commit 2dc983c5 authored by Tarun Kanti DebBarma's avatar Tarun Kanti DebBarma
Browse files

gpio/omap: cleanup prepare_for_idle and resume_after_idle 



Since *_prepare_for_idle() and *_resume_after_idle() are called
with interrupts disabled they should be kept as simple as possible.
So, moving most of the stuff to *_runtime_suspend/resume() callbacks.

To avoid invalid context restore happening in *_runtime_resume()
callback as a result of *_get_sync() call in *_gpio_probe(), update
bank->context_loss_count. This would make context restore condition
check false in the callback and skip restore until further
initialization take place. The workaround_enabled static variable
is now a member of struct gpio_bank.

Unlike most GPIO registers the OE has 0xffffffff as the default value.
To make sure invalid context is not restored, updating the OE context
with default value.

Signed-off-by: default avatarTarun Kanti DebBarma <tarun.kanti@ti.com>
Signed-off-by: default avatarCharulatha V <charu@ti.com>
Reviewed-by: default avatarSantosh Shilimkar <santosh.shilimkar@ti.com>
Reviewed-by: default avatarKevin Hilman <khilman@ti.com>
Signed-off-by: default avatarKevin Hilman <khilman@ti.com>
parent 065cd795

drivers/gpio/gpio-omap.c

+147 −98
Original line number Diff line number Diff line
@@ -29,6 +29,8 @@ 
#include <asm/gpio.h>

#include <asm/mach/irq.h>



#define OFF_MODE	1



static LIST_HEAD(omap_gpio_list);



struct gpio_regs {
@@ -73,6 +75,8 @@ struct gpio_bank { 
	u32 width;

	int context_loss_count;

	u16 id;

	int power_mode;

	bool workaround_enabled;



	void (*set_dataout)(struct gpio_bank *bank, int gpio, int enable);

	int (*get_context_loss_count)(struct device *dev);
@@ -905,6 +909,8 @@ static void omap_gpio_mod_init(struct gpio_bank *bank) 
	if (bank->regs->debounce_en)

		_gpio_rmw(base, bank->regs->debounce_en, 0, 1);



	/* Save OE default value (0xffffffff) in the context */

	bank->context.oe = __raw_readl(bank->base + bank->regs->direction);

	 /* Initialize interface clk ungated, module enabled */

	if (bank->regs->ctrl)

		_gpio_rmw(base, bank->regs->ctrl, 0, 1);
@@ -1127,29 +1133,27 @@ static int omap_gpio_resume(struct device *dev) 
}

#endif /* CONFIG_PM_SLEEP */



#if defined(CONFIG_PM_RUNTIME)

static void omap_gpio_save_context(struct gpio_bank *bank);

static void omap_gpio_restore_context(struct gpio_bank *bank);



void omap2_gpio_prepare_for_idle(int off_mode)

static int omap_gpio_runtime_suspend(struct device *dev)

{

	struct gpio_bank *bank;



	list_for_each_entry(bank, &omap_gpio_list, node) {

	struct platform_device *pdev = to_platform_device(dev);

	struct gpio_bank *bank = platform_get_drvdata(pdev);

	u32 l1 = 0, l2 = 0;

		int j;



		if (!bank->loses_context)

			continue;



		for (j = 0; j < hweight_long(bank->dbck_enable_mask); j++)

			clk_disable(bank->dbck);



		if (!off_mode)

			continue;

	unsigned long flags;



		/* If going to OFF, remove triggering for all

	spin_lock_irqsave(&bank->lock, flags);

	if (bank->power_mode != OFF_MODE) {

		bank->power_mode = 0;

		goto save_gpio_context;

	}

	/*

	 * If going to OFF, remove triggering for all

	 * non-wakeup GPIOs.  Otherwise spurious IRQs will be

		 * generated.  See OMAP2420 Errata item 1.101. */

	 * generated.  See OMAP2420 Errata item 1.101.

	 */

	if (!(bank->enabled_non_wakeup_gpios))

		goto save_gpio_context;
@@ -1166,47 +1170,44 @@ void omap2_gpio_prepare_for_idle(int off_mode) 
	__raw_writel(l1, bank->base + bank->regs->fallingdetect);

	__raw_writel(l2, bank->base + bank->regs->risingdetect);



save_gpio_context:

	bank->workaround_enabled = true;



save_gpio_context:

	if (bank->get_context_loss_count)

		bank->context_loss_count =

				bank->get_context_loss_count(bank->dev);



	omap_gpio_save_context(bank);

	spin_unlock_irqrestore(&bank->lock, flags);



		if (!pm_runtime_suspended(bank->dev))

			pm_runtime_put(bank->dev);

	}

	return 0;

}



void omap2_gpio_resume_after_idle(void)

static int omap_gpio_runtime_resume(struct device *dev)

{

	struct gpio_bank *bank;



	list_for_each_entry(bank, &omap_gpio_list, node) {

	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;

		int j;



		if (!bank->loses_context)

			continue;



		for (j = 0; j < hweight_long(bank->dbck_enable_mask); j++)

			clk_enable(bank->dbck);

	unsigned long flags;



		if (pm_runtime_suspended(bank->dev))

			pm_runtime_get_sync(bank->dev);

	spin_lock_irqsave(&bank->lock, flags);

	if (!bank->enabled_non_wakeup_gpios || !bank->workaround_enabled) {

		spin_unlock_irqrestore(&bank->lock, flags);

		return 0;

	}



	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

				|| !context_lost_cnt_after)

		if (context_lost_cnt_after != bank->context_loss_count ||

						!context_lost_cnt_after) {

			omap_gpio_restore_context(bank);

		} else {

			spin_unlock_irqrestore(&bank->lock, flags);

			return 0;

		}

	}



		if (!(bank->enabled_non_wakeup_gpios))

			continue;



	__raw_writel(bank->saved_fallingdetect,

			bank->base + bank->regs->fallingdetect);
@@ -1214,10 +1215,12 @@ void omap2_gpio_resume_after_idle(void) 
			bank->base + bank->regs->risingdetect);

	l = __raw_readl(bank->base + bank->regs->datain);



		/* Check if any of the non-wakeup interrupt GPIOs have changed

	/*

	 * Check if any of the non-wakeup interrupt GPIOs have changed

	 * state.  If so, generate an IRQ by software.  This is

	 * horribly racy, but it's the best we can do to work around

		 * this silicon bug. */

	 * this silicon bug.

	 */

	l ^= bank->saved_datain;

	l &= bank->enabled_non_wakeup_gpios;
@@ -1232,36 +1235,77 @@ void omap2_gpio_resume_after_idle(void) 
	gen1 &= ~(bank->saved_datain);



	/* FIXME: Consider GPIO IRQs with level detections properly! */

		gen = l & (~(bank->saved_fallingdetect) &

				~(bank->saved_risingdetect));

	gen = l & (~(bank->saved_fallingdetect) & ~(bank->saved_risingdetect));

	/* Consider all GPIO IRQs needed to be updated */

	gen |= gen0 | gen1;



	if (gen) {

		u32 old0, old1;



			old0 = __raw_readl(bank->base +

						bank->regs->leveldetect0);

			old1 = __raw_readl(bank->base +

						bank->regs->leveldetect1);

		old0 = __raw_readl(bank->base + bank->regs->leveldetect0);

		old1 = __raw_readl(bank->base + bank->regs->leveldetect1);



		if (cpu_is_omap24xx() || cpu_is_omap34xx()) {

				old0 |= gen;

				old1 |= gen;

			__raw_writel(old0 | gen, bank->base +

						bank->regs->leveldetect0);

			__raw_writel(old1 | gen, bank->base +

						bank->regs->leveldetect1);

		}



		if (cpu_is_omap44xx()) {

				old0 |= l;

				old1 |= l;

			}

			__raw_writel(old0, bank->base +

			__raw_writel(old0 | l, bank->base +

						bank->regs->leveldetect0);

			__raw_writel(old1, bank->base +

			__raw_writel(old1 | l, bank->base +

						bank->regs->leveldetect1);

		}

		__raw_writel(old0, bank->base + bank->regs->leveldetect0);

		__raw_writel(old1, bank->base + bank->regs->leveldetect1);

	}



	bank->workaround_enabled = false;

	spin_unlock_irqrestore(&bank->lock, flags);



	return 0;

}

#endif /* CONFIG_PM_RUNTIME */



void omap2_gpio_prepare_for_idle(int pwr_mode)

{

	struct gpio_bank *bank;



	list_for_each_entry(bank, &omap_gpio_list, node) {

		int j;



		if (!bank->mod_usage || !bank->loses_context)

			continue;



		bank->power_mode = pwr_mode;



		for (j = 0; j < hweight_long(bank->dbck_enable_mask); j++)

			clk_disable(bank->dbck);



		pm_runtime_put_sync_suspend(bank->dev);

	}

}



void omap2_gpio_resume_after_idle(void)

{

	struct gpio_bank *bank;



	list_for_each_entry(bank, &omap_gpio_list, node) {

		int j;



		if (!bank->mod_usage || !bank->loses_context)

			continue;



		for (j = 0; j < hweight_long(bank->dbck_enable_mask); j++)

			clk_enable(bank->dbck);



		pm_runtime_get_sync(bank->dev);

	}

}



#if defined(CONFIG_PM_RUNTIME)

static void omap_gpio_save_context(struct gpio_bank *bank)

{

	bank->context.irqenable1 =
@@ -1303,13 +1347,18 @@ static void omap_gpio_restore_context(struct gpio_bank *bank) 
				bank->base + bank->regs->fallingdetect);

	__raw_writel(bank->context.dataout, bank->base + bank->regs->dataout);

}

#endif /* CONFIG_PM_RUNTIME */

#else

#define omap_gpio_suspend NULL

#define omap_gpio_resume NULL

#define omap_gpio_runtime_suspend NULL

#define omap_gpio_runtime_resume NULL

#endif



static const struct dev_pm_ops gpio_pm_ops = {

	SET_SYSTEM_SLEEP_PM_OPS(omap_gpio_suspend, omap_gpio_resume)

	SET_RUNTIME_PM_OPS(omap_gpio_runtime_suspend, omap_gpio_runtime_resume,

									NULL)

};



static struct platform_driver omap_gpio_driver = {

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