diff mbox

[v2,05/18] GPIO: OMAP: Handle save/restore ctx in GPIO driver

Message ID 1308111776-29130-4-git-send-email-tarun.kanti@ti.com (mailing list archive)
State Changes Requested
Delegated to: Kevin Hilman
Headers show

Commit Message

Tarun Kanti DebBarma June 15, 2011, 4:22 a.m. UTC 
From: Charulatha V <charu@ti.com>

Modify omap_gpio_prepare_for_idle() & omap_gpio_resume_after_idle() functions
to handle save context & restore context respectively in the OMAP GPIO driver
itself instead of calling these functions from pm specific files.
For this, in gpio_prepare_for_idle(), call *_get_context_loss_count() and in
gpio_resume_after_idle() call it again. If the count is different, do restore
context. The workaround_enabled flag is no more required and is removed.

Signed-off-by: Charulatha V <charu@ti.com>
---
 arch/arm/mach-omap2/gpio.c             |   12 +++
 arch/arm/mach-omap2/pm34xx.c           |   14 ----
 arch/arm/plat-omap/include/plat/gpio.h |    5 +-
 drivers/gpio/gpio-omap.c               |  129 ++++++++++++++------------------
 4 files changed, 71 insertions(+), 89 deletions(-)

Comments

Kevin Hilman June 16, 2011, 4:34 p.m. UTC | #1 
Tarun Kanti DebBarma <tarun.kanti@ti.com> writes:

> From: Charulatha V <charu@ti.com>
>
> Modify omap_gpio_prepare_for_idle() & omap_gpio_resume_after_idle() functions
> to handle save context & restore context respectively in the OMAP GPIO driver
> itself instead of calling these functions from pm specific files.
> For this, in gpio_prepare_for_idle(), call *_get_context_loss_count() and in
> gpio_resume_after_idle() call it again. If the count is different, do restore
> context. The workaround_enabled flag is no more required and is removed.
>
> Signed-off-by: Charulatha V <charu@ti.com>

[...]

> @@ -1396,8 +1399,12 @@ void omap2_gpio_resume_after_idle(void)
>  		for (j = 0; j < hweight_long(bank->dbck_enable_mask); j++)
>  			clk_enable(bank->dbck);
>  
> -		if (!workaround_enabled)
> -			continue;
> +		if (bank->get_context_loss_count) {
> +			ctx_lost_cnt_after =
> +				bank->get_context_loss_count(bank->dev);
> +			if (ctx_lost_cnt_after != bank->ctx_loss_count)
> +				omap_gpio_restore_context(bank);
> +		}

Context should be also be restored if you cant know if it's been lost.
IOW, it should also be restored if !bank->get_context_loss_count.

>  		if (!(bank->enabled_non_wakeup_gpios))
>  			continue;
> @@ -1475,74 +1482,50 @@ void omap2_gpio_resume_after_idle(void)
>  			}
>  		}
>  	}
> -
>  }
>  
> -#endif
> -
> -#ifdef CONFIG_ARCH_OMAP3
> -void omap_gpio_save_context(void)
> +void omap_gpio_save_context(struct gpio_bank *bank)

Should also be made static.  Same for restore below.

Kevin
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Tarun Kanti DebBarma June 17, 2011, 5:41 a.m. UTC | #2 
> -----Original Message-----
> From: Hilman, Kevin
> Sent: Thursday, June 16, 2011 10:05 PM
> To: DebBarma, Tarun Kanti
> Cc: linux-omap@vger.kernel.org; Shilimkar, Santosh; tony@atomide.com
> Subject: Re: [PATCH v2 05/18] GPIO: OMAP: Handle save/restore ctx in GPIO
> driver
> 
> Tarun Kanti DebBarma <tarun.kanti@ti.com> writes:
> 
> > From: Charulatha V <charu@ti.com>
> >
> > Modify omap_gpio_prepare_for_idle() & omap_gpio_resume_after_idle()
> functions
> > to handle save context & restore context respectively in the OMAP GPIO
> driver
> > itself instead of calling these functions from pm specific files.
> > For this, in gpio_prepare_for_idle(), call *_get_context_loss_count()
> and in
> > gpio_resume_after_idle() call it again. If the count is different, do
> restore
> > context. The workaround_enabled flag is no more required and is removed.
> >
> > Signed-off-by: Charulatha V <charu@ti.com>
> 
> [...]
> 
> > @@ -1396,8 +1399,12 @@ void omap2_gpio_resume_after_idle(void)
> >  		for (j = 0; j < hweight_long(bank->dbck_enable_mask); j++)
> >  			clk_enable(bank->dbck);
> >
> > -		if (!workaround_enabled)
> > -			continue;
> > +		if (bank->get_context_loss_count) {
> > +			ctx_lost_cnt_after =
> > +				bank->get_context_loss_count(bank->dev);
> > +			if (ctx_lost_cnt_after != bank->ctx_loss_count)
> > +				omap_gpio_restore_context(bank);
> > +		}
> 
> Context should be also be restored if you cant know if it's been lost.
> IOW, it should also be restored if !bank->get_context_loss_count.
Ok, I will incorporate this condition as well.

> 
> >  		if (!(bank->enabled_non_wakeup_gpios))
> >  			continue;
> > @@ -1475,74 +1482,50 @@ void omap2_gpio_resume_after_idle(void)
> >  			}
> >  		}
> >  	}
> > -
> >  }
> >
> > -#endif
> > -
> > -#ifdef CONFIG_ARCH_OMAP3
> > -void omap_gpio_save_context(void)
> > +void omap_gpio_save_context(struct gpio_bank *bank)
> 
> Should also be made static.  Same for restore below.
Sure. Thanks.

BTW, there is another bug in this patch which I noticed later.
In *_probe, the following assignment got missed:

bank->get_context_loss_count = pdata->get_context_loss_count;

--
Tarun
> 
> Kevin
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diff mbox

Patch

diff --git a/arch/arm/mach-omap2/gpio.c b/arch/arm/mach-omap2/gpio.c
index 95195a8..2e65377 100644
--- a/arch/arm/mach-omap2/gpio.c
+++ b/arch/arm/mach-omap2/gpio.c
@@ -23,6 +23,7 @@ 
 
 #include <plat/omap_hwmod.h>
 #include <plat/omap_device.h>
+#include <plat/omap-pm.h>
 
 #include "powerdomain.h"
 
@@ -34,6 +35,16 @@  static struct omap_device_pm_latency omap_gpio_latency[] = {
 	},
 };
 
+#ifdef CONFIG_PM
+static int omap_gpio_get_context_loss(struct device *dev)
+{
+	return omap_pm_get_dev_context_loss_count(dev);
+}
+
+#else
+#define omap_gpio_get_context_loss NULL
+#endif
+
 static int omap2_gpio_dev_init(struct omap_hwmod *oh, void *unused)
 {
 	struct omap_device *od;
@@ -63,6 +74,7 @@  static int omap2_gpio_dev_init(struct omap_hwmod *oh, void *unused)
 	pdata->bank_width = dev_attr->bank_width;
 	pdata->dbck_flag = dev_attr->dbck_flag;
 	pdata->virtual_irq_start = IH_GPIO_BASE + 32 * (id - 1);
+	pdata->get_context_loss_count = omap_gpio_get_context_loss;
 
 	pdata->regs = kzalloc(sizeof(struct omap_gpio_reg_offs), GFP_KERNEL);
 	if (!pdata) {
diff --git a/arch/arm/mach-omap2/pm34xx.c b/arch/arm/mach-omap2/pm34xx.c
index 51d5a5c..0aaa32c 100644
--- a/arch/arm/mach-omap2/pm34xx.c
+++ b/arch/arm/mach-omap2/pm34xx.c
@@ -91,16 +91,6 @@  static struct powerdomain *mpu_pwrdm, *neon_pwrdm;
 static struct powerdomain *core_pwrdm, *per_pwrdm;
 static struct powerdomain *cam_pwrdm;
 
-static inline void omap3_per_save_context(void)
-{
-	omap_gpio_save_context();
-}
-
-static inline void omap3_per_restore_context(void)
-{
-	omap_gpio_restore_context();
-}
-
 static void omap3_enable_io_chain(void)
 {
 	int timeout = 0;
@@ -405,8 +395,6 @@  void omap_sram_idle(void)
 		omap_uart_prepare_idle(2);
 		omap_uart_prepare_idle(3);
 		omap2_gpio_prepare_for_idle(per_going_off);
-		if (per_next_state == PWRDM_POWER_OFF)
-				omap3_per_save_context();
 	}
 
 	/* CORE */
@@ -474,8 +462,6 @@  void omap_sram_idle(void)
 	if (per_next_state < PWRDM_POWER_ON) {
 		per_prev_state = pwrdm_read_prev_pwrst(per_pwrdm);
 		omap2_gpio_resume_after_idle();
-		if (per_prev_state == PWRDM_POWER_OFF)
-			omap3_per_restore_context();
 		omap_uart_resume_idle(2);
 		omap_uart_resume_idle(3);
 	}
diff --git a/arch/arm/plat-omap/include/plat/gpio.h b/arch/arm/plat-omap/include/plat/gpio.h
index 58d0bf2..f7798b5 100644
--- a/arch/arm/plat-omap/include/plat/gpio.h
+++ b/arch/arm/plat-omap/include/plat/gpio.h
@@ -201,14 +201,15 @@  struct omap_gpio_platform_data {
 	bool loses_context;	/* whether the bank would ever lose context */
 
 	struct omap_gpio_reg_offs *regs;
+
+	/* Return context loss count due to PM states changing */
+	int (*get_context_loss_count)(struct device *dev);
 };
 
 extern void omap2_gpio_prepare_for_idle(int off_mode);
 extern void omap2_gpio_resume_after_idle(void);
 extern void omap_set_gpio_debounce(int gpio, int enable);
 extern void omap_set_gpio_debounce_time(int gpio, int enable);
-extern void omap_gpio_save_context(void);
-extern void omap_gpio_restore_context(void);
 /*-------------------------------------------------------------------------*/
 
 /* Wrappers for "new style" GPIO calls, using the new infrastructure
diff --git a/drivers/gpio/gpio-omap.c b/drivers/gpio/gpio-omap.c
index d461558..e7b3391 100644
--- a/drivers/gpio/gpio-omap.c
+++ b/drivers/gpio/gpio-omap.c
@@ -72,9 +72,11 @@  struct gpio_bank {
 	bool loses_context;
 	int stride;
 	u32 width;
+	u32 ctx_loss_count;
 	u16 id;
 
 	void (*set_dataout)(struct gpio_bank *bank, int gpio, int enable);
+	int (*get_context_loss_count)(struct device *dev);
 
 	struct omap_gpio_reg_offs *regs;
 };
@@ -1312,11 +1314,11 @@  static struct syscore_ops omap_gpio_syscore_ops = {
 
 #ifdef CONFIG_ARCH_OMAP2PLUS
 
-static int workaround_enabled;
+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)
 {
-	int c = 0;
 	struct gpio_bank *bank;
 
 	list_for_each_entry(bank, &omap_gpio_list, node) {
@@ -1336,7 +1338,7 @@  void omap2_gpio_prepare_for_idle(int off_mode)
 		 * non-wakeup GPIOs.  Otherwise spurious IRQs will be
 		 * generated.  See OMAP2420 Errata item 1.101. */
 		if (!(bank->enabled_non_wakeup_gpios))
-			continue;
+			goto save_gpio_ctx;
 
 		if (cpu_is_omap24xx() || cpu_is_omap34xx()) {
 			bank->saved_datain = __raw_readl(bank->base +
@@ -1373,13 +1375,13 @@  void omap2_gpio_prepare_for_idle(int off_mode)
 			__raw_writel(l2, bank->base + OMAP4_GPIO_RISINGDETECT);
 		}
 
-		c++;
-	}
-	if (!c) {
-		workaround_enabled = 0;
-		return;
+save_gpio_ctx:
+		if (bank->get_context_loss_count)
+			bank->ctx_loss_count =
+				bank->get_context_loss_count(bank->dev);
+
+		omap_gpio_save_context(bank);
 	}
-	workaround_enabled = 1;
 }
 
 void omap2_gpio_resume_after_idle(void)
@@ -1387,6 +1389,7 @@  void omap2_gpio_resume_after_idle(void)
 	struct gpio_bank *bank;
 
 	list_for_each_entry(bank, &omap_gpio_list, node) {
+		u32 ctx_lost_cnt_after;
 		u32 l = 0, gen, gen0, gen1;
 		int j;
 
@@ -1396,8 +1399,12 @@  void omap2_gpio_resume_after_idle(void)
 		for (j = 0; j < hweight_long(bank->dbck_enable_mask); j++)
 			clk_enable(bank->dbck);
 
-		if (!workaround_enabled)
-			continue;
+		if (bank->get_context_loss_count) {
+			ctx_lost_cnt_after =
+				bank->get_context_loss_count(bank->dev);
+			if (ctx_lost_cnt_after != bank->ctx_loss_count)
+				omap_gpio_restore_context(bank);
+		}
 
 		if (!(bank->enabled_non_wakeup_gpios))
 			continue;
@@ -1475,74 +1482,50 @@  void omap2_gpio_resume_after_idle(void)
 			}
 		}
 	}
-
 }
 
-#endif
-
-#ifdef CONFIG_ARCH_OMAP3
-void omap_gpio_save_context(void)
+void omap_gpio_save_context(struct gpio_bank *bank)
 {
-	struct gpio_bank *bank;
-
-	list_for_each_entry(bank, &omap_gpio_list, node) {
-
-		if (!bank->loses_context)
-			continue;
-
-		bank->context.irqenable1 =
-			__raw_readl(bank->base + OMAP24XX_GPIO_IRQENABLE1);
-		bank->context.irqenable2 =
-			__raw_readl(bank->base + OMAP24XX_GPIO_IRQENABLE2);
-		bank->context.wake_en =
-			__raw_readl(bank->base + OMAP24XX_GPIO_WAKE_EN);
-		bank->context.ctrl =
-			__raw_readl(bank->base + OMAP24XX_GPIO_CTRL);
-		bank->context.oe =
-			__raw_readl(bank->base + OMAP24XX_GPIO_OE);
-		bank->context.leveldetect0 =
-			__raw_readl(bank->base + OMAP24XX_GPIO_LEVELDETECT0);
-		bank->context.leveldetect1 =
-			__raw_readl(bank->base + OMAP24XX_GPIO_LEVELDETECT1);
-		bank->context.risingdetect =
-			__raw_readl(bank->base + OMAP24XX_GPIO_RISINGDETECT);
-		bank->context.fallingdetect =
-			__raw_readl(bank->base + OMAP24XX_GPIO_FALLINGDETECT);
-		bank->context.dataout =
-			__raw_readl(bank->base + OMAP24XX_GPIO_DATAOUT);
-	}
+	bank->context.irqenable1 =
+		__raw_readl(bank->base + OMAP24XX_GPIO_IRQENABLE1);
+	bank->context.irqenable2 =
+		__raw_readl(bank->base + OMAP24XX_GPIO_IRQENABLE2);
+	bank->context.wake_en =
+		__raw_readl(bank->base + OMAP24XX_GPIO_WAKE_EN);
+	bank->context.ctrl = __raw_readl(bank->base + OMAP24XX_GPIO_CTRL);
+	bank->context.oe = __raw_readl(bank->base + OMAP24XX_GPIO_OE);
+	bank->context.leveldetect0 =
+		__raw_readl(bank->base + OMAP24XX_GPIO_LEVELDETECT0);
+	bank->context.leveldetect1 =
+		__raw_readl(bank->base + OMAP24XX_GPIO_LEVELDETECT1);
+	bank->context.risingdetect =
+		__raw_readl(bank->base + OMAP24XX_GPIO_RISINGDETECT);
+	bank->context.fallingdetect =
+		__raw_readl(bank->base + OMAP24XX_GPIO_FALLINGDETECT);
+	bank->context.dataout =
+		__raw_readl(bank->base + OMAP24XX_GPIO_DATAOUT);
 }
 
-void omap_gpio_restore_context(void)
+void omap_gpio_restore_context(struct gpio_bank *bank)
 {
-	struct gpio_bank *bank;
-
-	list_for_each_entry(bank, &omap_gpio_list, node) {
-
-		if (!bank->loses_context)
-			continue;
-
-		__raw_writel(bank->context.irqenable1,
-				bank->base + OMAP24XX_GPIO_IRQENABLE1);
-		__raw_writel(bank->context.irqenable2,
-				bank->base + OMAP24XX_GPIO_IRQENABLE2);
-		__raw_writel(bank->context.wake_en,
-				bank->base + OMAP24XX_GPIO_WAKE_EN);
-		__raw_writel(bank->context.ctrl,
-				bank->base + OMAP24XX_GPIO_CTRL);
-		__raw_writel(bank->context.oe,
-				bank->base + OMAP24XX_GPIO_OE);
-		__raw_writel(bank->context.leveldetect0,
-				bank->base + OMAP24XX_GPIO_LEVELDETECT0);
-		__raw_writel(bank->context.leveldetect1,
-				bank->base + OMAP24XX_GPIO_LEVELDETECT1);
-		__raw_writel(bank->context.risingdetect,
-				bank->base + OMAP24XX_GPIO_RISINGDETECT);
-		__raw_writel(bank->context.fallingdetect,
-				bank->base + OMAP24XX_GPIO_FALLINGDETECT);
-		__raw_writel(bank->context.dataout,
-				bank->base + OMAP24XX_GPIO_DATAOUT);
-	}
+	__raw_writel(bank->context.irqenable1,
+			bank->base + OMAP24XX_GPIO_IRQENABLE1);
+	__raw_writel(bank->context.irqenable2,
+			bank->base + OMAP24XX_GPIO_IRQENABLE2);
+	__raw_writel(bank->context.wake_en,
+			bank->base + OMAP24XX_GPIO_WAKE_EN);
+	__raw_writel(bank->context.ctrl, bank->base + OMAP24XX_GPIO_CTRL);
+	__raw_writel(bank->context.oe, bank->base + OMAP24XX_GPIO_OE);
+	__raw_writel(bank->context.leveldetect0,
+			bank->base + OMAP24XX_GPIO_LEVELDETECT0);
+	__raw_writel(bank->context.leveldetect1,
+			bank->base + OMAP24XX_GPIO_LEVELDETECT1);
+	__raw_writel(bank->context.risingdetect,
+			bank->base + OMAP24XX_GPIO_RISINGDETECT);
+	__raw_writel(bank->context.fallingdetect,
+			bank->base + OMAP24XX_GPIO_FALLINGDETECT);
+	__raw_writel(bank->context.dataout,
+			bank->base + OMAP24XX_GPIO_DATAOUT);
 }
 #endif