[PATCH v9 04/25] gpio/omap: handle save/restore context in GPIO driver

From: Tarun Kanti DebBarma
Date: Thu Feb 02 2012 - 12:34:16 EST

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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.

Signed-off-by: Charulatha V <charu@xxxxxx>
Signed-off-by: Tarun Kanti DebBarma <tarun.kanti@xxxxxx>
Reviewed-by: Santosh Shilimkar <santosh.shilimkar@xxxxxx>
Acked-by: Tony Lindgren <tony@xxxxxxxxxxx>
---
arch/arm/mach-omap2/gpio.c | 3 +-
arch/arm/mach-omap2/pm34xx.c | 14 ----
arch/arm/plat-omap/include/plat/gpio.h | 5 +-
drivers/gpio/gpio-omap.c | 131 ++++++++++++++------------------
4 files changed, 63 insertions(+), 90 deletions(-)

diff --git a/arch/arm/mach-omap2/gpio.c b/arch/arm/mach-omap2/gpio.c
index 076be34..f84db8f 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"

@@ -55,7 +56,7 @@ 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_pm_get_dev_context_loss_count;
pdata->regs = kzalloc(sizeof(struct omap_gpio_reg_offs), GFP_KERNEL);
if (!pdata) {
pr_err("gpio%d: Memory allocation failed\n", id);
diff --git a/arch/arm/mach-omap2/pm34xx.c b/arch/arm/mach-omap2/pm34xx.c
index fc69875..59c6dc1 100644
--- a/arch/arm/mach-omap2/pm34xx.c
+++ b/arch/arm/mach-omap2/pm34xx.c
@@ -75,16 +75,6 @@ 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;
@@ -332,8 +322,6 @@ void omap_sram_idle(void)
if (per_next_state < PWRDM_POWER_ON) {
per_going_off = (per_next_state == PWRDM_POWER_OFF) ? 1 : 0;
omap2_gpio_prepare_for_idle(per_going_off);
- if (per_next_state == PWRDM_POWER_OFF)
- omap3_per_save_context();
}

/* CORE */
@@ -399,8 +387,6 @@ 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();
}

/* Disable IO-PAD and IO-CHAIN wakeup */
diff --git a/arch/arm/plat-omap/include/plat/gpio.h b/arch/arm/plat-omap/include/plat/gpio.h
index 6eb035c..c1ddc5a 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 6788c8a..a1a3b9d 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;
+ int context_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;
};
@@ -1179,6 +1181,7 @@ static int __devinit omap_gpio_probe(struct platform_device *pdev)
bank->stride = pdata->bank_stride;
bank->width = pdata->bank_width;
bank->loses_context = pdata->loses_context;
+ bank->get_context_loss_count = pdata->get_context_loss_count;
bank->regs = pdata->regs;

if (bank->regs->set_dataout && bank->regs->clr_dataout)
@@ -1323,11 +1326,11 @@ 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) {
@@ -1347,7 +1350,7 @@ 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_context;

if (cpu_is_omap24xx() || cpu_is_omap34xx()) {
bank->saved_datain = __raw_readl(bank->base +
@@ -1384,13 +1387,13 @@ 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_context:
+ if (bank->get_context_loss_count)
+ bank->context_loss_count =
+ bank->get_context_loss_count(bank->dev);
+
+ omap_gpio_save_context(bank);
}
- workaround_enabled = 1;
}

void omap2_gpio_resume_after_idle(void)
@@ -1398,6 +1401,7 @@ void omap2_gpio_resume_after_idle(void)
struct gpio_bank *bank;

list_for_each_entry(bank, &omap_gpio_list, node) {
+ int context_lost_cnt_after;
u32 l = 0, gen, gen0, gen1;
int j;

@@ -1407,8 +1411,13 @@ 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) {
+ context_lost_cnt_after =
+ bank->get_context_loss_count(bank->dev);
+ if (context_lost_cnt_after != bank->context_loss_count
+ || !context_lost_cnt_after)
+ omap_gpio_restore_context(bank);
+ }

if (!(bank->enabled_non_wakeup_gpios))
continue;
@@ -1486,74 +1495,50 @@ void omap2_gpio_resume_after_idle(void)
}
}
}
-
}

-#endif
-
-#ifdef CONFIG_ARCH_OMAP3
-void omap_gpio_save_context(void)
+static 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)
+static 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

--
1.7.0.4

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Next message: Paul E. McKenney: "Re: [PATCH RFC tip/core/rcu 21/41] rcu: Inform RCU of irq_exit()activity"
Previous message: Tarun Kanti DebBarma: "[PATCH v9 16/25] gpio/omap: use pm-runtime framework"
In reply to: Tarun Kanti DebBarma: "[PATCH v9 16/25] gpio/omap: use pm-runtime framework"
Next in thread: Tarun Kanti DebBarma: "[PATCH v9 17/25] gpio/omap: optimize suspend and resume functions"
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