[PATCH 4/7] OMAP: GPIO: handle save/restore ctx in GPIO driver

Varadarajan, Charulatha
2011-04-18T15:03:53Z

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(), use
omap_device_get_context_loss_count() and in gpio_resume_after_idle()
call it again. If the count is different, do restore context.

context lost count is modified in omap_sram_idle() path when
pwrdm_post_transition() is called. But pwrdm_post_transition() is called
only after omap_gpio_resume_after_idle() is called. Hence correct this
so that context lost count is modified before calling
omap_gpio_resume_after_idle().

omap_gpio_prepare_for_idle() & omap_gpio_resume_after_idle()
do nothing if none of the GPIOs in a bank is being used.

Also remove usage of cpu_is_* checks from the above mentioned
functions and fix the multi-line comment style

Signed-off-by: Charulatha V <charu@ti.com>
---
Note that the usage of bank->method checks would be re-addressed
during OMAP GPIO cleanup series which would follow this patch series

arch/arm/mach-omap2/pm34xx.c | 22 +---
arch/arm/plat-omap/gpio.c | 226 ++++++++++++++++---------------
arch/arm/plat-omap/include/plat/gpio.h | 2 -
3 files changed, 122 insertions(+), 128 deletions(-)

diff --git a/arch/arm/mach-omap2/pm34xx.c b/arch/arm/mach-omap2/pm34xx.c
index 0c5e3a4..682d147 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;
@@ -395,8 +385,10 @@ void omap_sram_idle(void)
if (!is_suspending())
if (per_next_state < PWRDM_POWER_ON ||
core_next_state < PWRDM_POWER_ON)
- if (!console_trylock())
+ if (!console_trylock()) {
+ pwrdm_post_transition();
goto console_still_active;
+ }

/* PER */
if (per_next_state < PWRDM_POWER_ON) {
@@ -404,8 +396,6 @@ 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 */
@@ -467,12 +457,12 @@ void omap_sram_idle(void)
}
omap3_intc_resume_idle();

+ pwrdm_post_transition();
+
/* PER */
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);
}
@@ -490,8 +480,6 @@ console_still_active:
omap3_disable_io_chain();
}

- pwrdm_post_transition();
-
clkdm_allow_idle(mpu_pwrdm->pwrdm_clkdms[0]);
}

diff --git a/arch/arm/plat-omap/gpio.c b/arch/arm/plat-omap/gpio.c
index e68da08..5d4ed6c 100644
--- a/arch/arm/plat-omap/gpio.c
+++ b/arch/arm/plat-omap/gpio.c
@@ -24,6 +24,8 @@
#include <linux/slab.h>
#include <linux/pm_runtime.h>

+#include <plat/omap_device.h>
+
#include <mach/hardware.h>
#include <asm/irq.h>
#include <mach/irqs.h>
@@ -173,6 +175,7 @@ struct gpio_bank {
bool dbck_flag;
int stride;
bool looses_context;
+ u32 ctx_lost_cnt_before;
};

/*
@@ -1852,6 +1855,8 @@ static struct sys_device omap_gpio_device = {
#endif

#ifdef CONFIG_ARCH_OMAP2PLUS
+static void omap_gpio_save_context(struct gpio_bank *bank);
+static void omap_gpio_restore_context(struct gpio_bank *bank);

static int workaround_enabled;

@@ -1861,9 +1866,14 @@ void omap2_gpio_prepare_for_idle(int off_mode)

for (i = 0; i < gpio_bank_count; i++) {
struct gpio_bank *bank = &gpio_bank[i];
+ struct platform_device *pdev;
u32 l1 = 0, l2 = 0;
int j;

+ /* If the gpio bank is not used, do nothing */
+ if (!bank->mod_usage)
+ continue;
+
if (!bank->looses_context)
continue;

@@ -1873,22 +1883,22 @@ void omap2_gpio_prepare_for_idle(int off_mode)
if (!off_mode)
continue;

- /* If going to OFF, remove triggering for all
+ /*
+ * 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))
- continue;
+ goto save_gpio_ctx;

- if (cpu_is_omap24xx() || cpu_is_omap34xx()) {
+ if (bank->method == METHOD_GPIO_24XX) {
bank->saved_datain = __raw_readl(bank->base +
OMAP24XX_GPIO_DATAIN);
l1 = __raw_readl(bank->base +
OMAP24XX_GPIO_FALLINGDETECT);
l2 = __raw_readl(bank->base +
OMAP24XX_GPIO_RISINGDETECT);
- }
-
- if (cpu_is_omap44xx()) {
+ } else if (bank->method == METHOD_GPIO_44XX) {
bank->saved_datain = __raw_readl(bank->base +
OMAP4_GPIO_DATAIN);
l1 = __raw_readl(bank->base +
@@ -1902,19 +1912,23 @@ void omap2_gpio_prepare_for_idle(int off_mode)
l1 &= ~bank->enabled_non_wakeup_gpios;
l2 &= ~bank->enabled_non_wakeup_gpios;

- if (cpu_is_omap24xx() || cpu_is_omap34xx()) {
+ if (bank->method == METHOD_GPIO_24XX) {
__raw_writel(l1, bank->base +
OMAP24XX_GPIO_FALLINGDETECT);
__raw_writel(l2, bank->base +
OMAP24XX_GPIO_RISINGDETECT);
- }
-
- if (cpu_is_omap44xx()) {
+ } else if (bank->method == METHOD_GPIO_44XX) {
__raw_writel(l1, bank->base + OMAP4_GPIO_FALLINGDETECT);
__raw_writel(l2, bank->base + OMAP4_GPIO_RISINGDETECT);
}

c++;
+
+save_gpio_ctx:
+ pdev = to_platform_device(bank->dev);
+ bank->ctx_lost_cnt_before =
+ omap_device_get_context_loss_count(pdev);
+ omap_gpio_save_context(bank);
}
if (!c) {
workaround_enabled = 0;
@@ -1926,33 +1940,43 @@ void omap2_gpio_prepare_for_idle(int off_mode)
void omap2_gpio_resume_after_idle(void)
{
int i;
+ u32 ctx_lost_cnt_after;

for (i = 0; i < gpio_bank_count; i++) {
struct gpio_bank *bank = &gpio_bank[i];
+ struct platform_device *pdev;
u32 l = 0, gen, gen0, gen1;
int j;

+ /* If the gpio bank is not used, do nothing */
+ if (!bank->mod_usage)
+ continue;
+
if (!bank->looses_context)
continue;

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

- if (!workaround_enabled)
+ pdev = to_platform_device(bank->dev);
+ ctx_lost_cnt_after = omap_device_get_context_loss_count(pdev);
+
+ if (ctx_lost_cnt_after == bank->ctx_lost_cnt_before)
continue;

+ if (!workaround_enabled)
+ goto restore_gpio_ctx;
+
if (!(bank->enabled_non_wakeup_gpios))
- continue;
+ goto restore_gpio_ctx;

- if (cpu_is_omap24xx() || cpu_is_omap34xx()) {
+ if (bank->method == METHOD_GPIO_24XX) {
__raw_writel(bank->saved_fallingdetect,
bank->base + OMAP24XX_GPIO_FALLINGDETECT);
__raw_writel(bank->saved_risingdetect,
bank->base + OMAP24XX_GPIO_RISINGDETECT);
l = __raw_readl(bank->base + OMAP24XX_GPIO_DATAIN);
- }
-
- if (cpu_is_omap44xx()) {
+ } else if (bank->method == METHOD_GPIO_44XX) {
__raw_writel(bank->saved_fallingdetect,
bank->base + OMAP4_GPIO_FALLINGDETECT);
__raw_writel(bank->saved_risingdetect,
@@ -1960,10 +1984,12 @@ void omap2_gpio_resume_after_idle(void)
l = __raw_readl(bank->base + OMAP4_GPIO_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;

@@ -1986,7 +2012,7 @@ void omap2_gpio_resume_after_idle(void)
if (gen) {
u32 old0, old1;

- if (cpu_is_omap24xx() || cpu_is_omap34xx()) {
+ if (bank->method == METHOD_GPIO_24XX) {
old0 = __raw_readl(bank->base +
OMAP24XX_GPIO_LEVELDETECT0);
old1 = __raw_readl(bank->base +
@@ -1999,9 +2025,7 @@ void omap2_gpio_resume_after_idle(void)
OMAP24XX_GPIO_LEVELDETECT0);
__raw_writel(old1, bank->base +
OMAP24XX_GPIO_LEVELDETECT1);
- }
-
- if (cpu_is_omap44xx()) {
+ } else if (bank->method == METHOD_GPIO_44XX) {
old0 = __raw_readl(bank->base +
OMAP4_GPIO_LEVELDETECT0);
old1 = __raw_readl(bank->base +
@@ -2016,123 +2040,107 @@ void omap2_gpio_resume_after_idle(void)
OMAP4_GPIO_LEVELDETECT1);
}
}
+
+restore_gpio_ctx:
+ omap_gpio_restore_context(bank);
}

}

-#endif
-
-void omap_gpio_save_context(void)
+void omap_gpio_save_context(struct gpio_bank *bank)
{
- int i;
-
- for (i = 0; i < gpio_bank_count; i++) {
- struct gpio_bank *bank = &gpio_bank[i];
-
- if (!bank->looses_context)
- continue;
-
- if (bank->method == METHOD_GPIO_24XX) {
- bank->context.irqenable1 = __raw_readl(
+ if (bank->method == METHOD_GPIO_24XX) {
+ bank->context.irqenable1 = __raw_readl(
bank->base + OMAP24XX_GPIO_IRQENABLE1);
- bank->context.irqenable2 = __raw_readl(
+ bank->context.irqenable2 = __raw_readl(
bank->base + OMAP24XX_GPIO_IRQENABLE2);
- bank->context.wake_en = __raw_readl(
+ bank->context.wake_en = __raw_readl(
bank->base + OMAP24XX_GPIO_WAKE_EN);
- bank->context.ctrl = __raw_readl(
+ bank->context.ctrl = __raw_readl(
bank->base + OMAP24XX_GPIO_CTRL);
- bank->context.oe = __raw_readl(
+ bank->context.oe = __raw_readl(
bank->base + OMAP24XX_GPIO_OE);
- bank->context.leveldetect0 = __raw_readl(bank->base +
+ bank->context.leveldetect0 = __raw_readl(bank->base +
OMAP24XX_GPIO_LEVELDETECT0);
- bank->context.leveldetect1 = __raw_readl(bank->base +
+ bank->context.leveldetect1 = __raw_readl(bank->base +
OMAP24XX_GPIO_LEVELDETECT1);
- bank->context.risingdetect = __raw_readl(bank->base +
+ bank->context.risingdetect = __raw_readl(bank->base +
OMAP24XX_GPIO_RISINGDETECT);
- bank->context.fallingdetect = __raw_readl(bank->base +
+ bank->context.fallingdetect = __raw_readl(bank->base +
OMAP24XX_GPIO_FALLINGDETECT);
- bank->context.dataout = __raw_readl(
+ bank->context.dataout = __raw_readl(
bank->base + OMAP24XX_GPIO_DATAOUT);
- } else if (bank->method == METHOD_GPIO_44XX) {
- bank->context.irqenable1 = __raw_readl(
+ } else if (bank->method == METHOD_GPIO_44XX) {
+ bank->context.irqenable1 = __raw_readl(
bank->base + OMAP4_GPIO_IRQSTATUSSET0);
- bank->context.irqenable2 = __raw_readl(
+ bank->context.irqenable2 = __raw_readl(
bank->base + OMAP4_GPIO_IRQSTATUSSET1);
- bank->context.wake_en = __raw_readl(
+ bank->context.wake_en = __raw_readl(
bank->base + OMAP4_GPIO_IRQWAKEN0);
- bank->context.ctrl = __raw_readl(
+ bank->context.ctrl = __raw_readl(
bank->base + OMAP4_GPIO_CTRL);
- bank->context.oe = __raw_readl(
+ bank->context.oe = __raw_readl(
bank->base + OMAP24XX_GPIO_OE);
- bank->context.leveldetect0 = __raw_readl(bank->base +
+ bank->context.leveldetect0 = __raw_readl(bank->base +
OMAP4_GPIO_LEVELDETECT0);
- bank->context.leveldetect1 = __raw_readl(bank->base +
+ bank->context.leveldetect1 = __raw_readl(bank->base +
OMAP4_GPIO_LEVELDETECT1);
- bank->context.risingdetect = __raw_readl(bank->base +
+ bank->context.risingdetect = __raw_readl(bank->base +
OMAP4_GPIO_RISINGDETECT);
- bank->context.fallingdetect = __raw_readl(bank->base +
+ bank->context.fallingdetect = __raw_readl(bank->base +
OMAP4_GPIO_FALLINGDETECT);
- bank->context.dataout = __raw_readl(
+ bank->context.dataout = __raw_readl(
bank->base + OMAP4_GPIO_DATAOUT);
- }
}
}

-void omap_gpio_restore_context(void)
+void omap_gpio_restore_context(struct gpio_bank *bank)
{
- int i;
-
- for (i = 0; i < gpio_bank_count; i++) {
- struct gpio_bank *bank = &gpio_bank[i];
-
- if (!bank->looses_context)
- continue;
-
- if (bank->method == METHOD_GPIO_24XX) {
- __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);
- } else if (bank->method == METHOD_GPIO_44XX) {
- __raw_writel(bank->context.irqenable1, bank->base +
- OMAP4_GPIO_IRQSTATUSSET0);
- __raw_writel(bank->context.irqenable2, bank->base +
- OMAP4_GPIO_IRQSTATUSSET1);
- __raw_writel(bank->context.wake_en, bank->base +
- OMAP4_GPIO_IRQWAKEN0);
- __raw_writel(bank->context.ctrl, bank->base +
- OMAP4_GPIO_CTRL);
- __raw_writel(bank->context.oe, bank->base +
- OMAP24XX_GPIO_OE);
- __raw_writel(bank->context.leveldetect0, bank->base +
- OMAP4_GPIO_LEVELDETECT0);
- __raw_writel(bank->context.leveldetect1, bank->base +
- OMAP4_GPIO_LEVELDETECT1);
- __raw_writel(bank->context.risingdetect, bank->base +
- OMAP4_GPIO_RISINGDETECT);
- __raw_writel(bank->context.fallingdetect, bank->base +
- OMAP4_GPIO_FALLINGDETECT);
- __raw_writel(bank->context.dataout, bank->base +
- OMAP4_GPIO_DATAOUT);
- }
+ if (bank->method == METHOD_GPIO_24XX) {
+ __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);
+ } else if (bank->method == METHOD_GPIO_44XX) {
+ __raw_writel(bank->context.irqenable1, bank->base +
+ OMAP4_GPIO_IRQSTATUSSET0);
+ __raw_writel(bank->context.irqenable2, bank->base +
+ OMAP4_GPIO_IRQSTATUSSET1);
+ __raw_writel(bank->context.wake_en, bank->base +
+ OMAP4_GPIO_IRQWAKEN0);
+ __raw_writel(bank->context.ctrl, bank->base +
+ OMAP4_GPIO_CTRL);
+ __raw_writel(bank->context.oe, bank->base +
+ OMAP24XX_GPIO_OE);
+ __raw_writel(bank->context.leveldetect0, bank->base +
+ OMAP4_GPIO_LEVELDETECT0);
+ __raw_writel(bank->context.leveldetect1, bank->base +
+ OMAP4_GPIO_LEVELDETECT1);
+ __raw_writel(bank->context.risingdetect, bank->base +
+ OMAP4_GPIO_RISINGDETECT);
+ __raw_writel(bank->context.fallingdetect, bank->base +
+ OMAP4_GPIO_FALLINGDETECT);
+ __raw_writel(bank->context.dataout, bank->base +
+ OMAP4_GPIO_DATAOUT);
}
}
+#endif

static struct platform_driver omap_gpio_driver = {
.probe = omap_gpio_probe,
diff --git a/arch/arm/plat-omap/include/plat/gpio.h b/arch/arm/plat-omap/include/plat/gpio.h
index 15aeb71..84b9106 100644
--- a/arch/arm/plat-omap/include/plat/gpio.h
+++ b/arch/arm/plat-omap/include/plat/gpio.h
@@ -87,8 +87,6 @@ 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
--
1.7.1