[PATCH 6/7] OMAP: GPIO: Cleanup prepare_for_idle/resume

Varadarajan, Charulatha
2011-04-18T15:03:49Z

From: Charulatha V <charu@ti.com>

Use a function named gpio_bank_handle_idle() in
omap_gpio_prepare_for_idle() to do the following:

* debounce clock disable
* if the next powerdomain state for the bank is off-mode:
- remove triggering for all non-wakeup GPIOs (this is handled by
a new function named omap_gpio_idle_handle_errata_i468())
- save context

Also handle omap_gpio_resume_after_idle() in a
similar way, using a function gpio_bank_handle_resume().

This would be helpful while modifying OMAP GPIO driver to use
PM runtime framework.

Signed-off-by: Charulatha V <charu@ti.com>
---
arch/arm/plat-omap/gpio.c | 350 ++++++++++++++++++++++++---------------------
1 files changed, 187 insertions(+), 163 deletions(-)

diff --git a/arch/arm/plat-omap/gpio.c b/arch/arm/plat-omap/gpio.c
index 5933c98..7660c06 100644
--- a/arch/arm/plat-omap/gpio.c
+++ b/arch/arm/plat-omap/gpio.c
@@ -1747,6 +1747,187 @@ static int __devinit omap_gpio_probe(struct platform_device *pdev)
return 0;
}

+#ifdef CONFIG_ARCH_OMAP2PLUS
+static int is_pwrdm_nxt_state_off;
+
+static inline void omap_gpio_idle_handle_errata_i468(struct gpio_bank *bank)
+{
+ u32 l1 = 0, l2 = 0;
+
+ /*
+ * If going to OFF, remove triggering for all
+ * non-wakeup GPIOs. Otherwise spurious IRQs will be
+ * generated. See OMAP2420 Errata item 1.101.
+ */
+ if (!(bank->enabled_non_wakeup_gpios))
+ return;
+
+ 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);
+ } else if (bank->method == METHOD_GPIO_44XX) {
+ bank->saved_datain = __raw_readl(bank->base +
+ OMAP4_GPIO_DATAIN);
+
+ l1 = __raw_readl(bank->base + OMAP4_GPIO_FALLINGDETECT);
+ l2 = __raw_readl(bank->base + OMAP4_GPIO_RISINGDETECT);
+ }
+
+ bank->saved_fallingdetect = l1;
+ bank->saved_risingdetect = l2;
+ l1 &= ~bank->enabled_non_wakeup_gpios;
+ l2 &= ~bank->enabled_non_wakeup_gpios;
+
+ if (bank->method == METHOD_GPIO_24XX) {
+ __raw_writel(l1, bank->base + OMAP24XX_GPIO_FALLINGDETECT);
+ __raw_writel(l2, bank->base + OMAP24XX_GPIO_RISINGDETECT);
+ } else if (bank->method == METHOD_GPIO_44XX) {
+ __raw_writel(l1, bank->base + OMAP4_GPIO_FALLINGDETECT);
+ __raw_writel(l2, bank->base + OMAP4_GPIO_RISINGDETECT);
+ }
+
+ bank->off_mode_wkup_wa_enabled = true;
+}
+
+static inline void omap_gpio_resume_handle_errata_i468(struct gpio_bank *bank)
+{
+ u32 l = 0, gen, gen0, gen1;
+
+ if (!bank->off_mode_wkup_wa_enabled)
+ return;
+
+ bank->off_mode_wkup_wa_enabled = false;
+
+ if (!(bank->enabled_non_wakeup_gpios))
+ return;
+
+ 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);
+ } else if (bank->method == METHOD_GPIO_44XX) {
+ __raw_writel(bank->saved_fallingdetect,
+ bank->base + OMAP4_GPIO_FALLINGDETECT);
+ __raw_writel(bank->saved_risingdetect,
+ bank->base + OMAP4_GPIO_RISINGDETECT);
+
+ l = __raw_readl(bank->base + OMAP4_GPIO_DATAIN);
+ }
+
+ /*
+ * 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.
+ */
+ l ^= bank->saved_datain;
+ l &= bank->enabled_non_wakeup_gpios;
+
+ /*
+ * No need to generate IRQs for the rising edge for gpio IRQs
+ * configured with falling edge only; and vice versa.
+ */
+ gen0 = l & bank->saved_fallingdetect;
+ gen0 &= bank->saved_datain;
+ gen1 = l & bank->saved_risingdetect;
+ gen1 &= ~(bank->saved_datain);
+
+ /* FIXME: Consider GPIO IRQs with level detections properly! */
+ gen = l & (~(bank->saved_fallingdetect) & ~(bank->saved_risingdetect));
+
+ /* Consider all GPIO IRQs needed to be updated */
+ gen |= gen0 | gen1;
+
+ if (gen) {
+ u32 old0, old1;
+
+ if (bank->method == METHOD_GPIO_24XX) {
+ old0 = __raw_readl(bank->base +
+ OMAP24XX_GPIO_LEVELDETECT0);
+ old1 = __raw_readl(bank->base +
+ OMAP24XX_GPIO_LEVELDETECT1);
+ __raw_writel(old0 | gen, bank->base +
+ OMAP24XX_GPIO_LEVELDETECT0);
+ __raw_writel(old1 | gen, bank->base +
+ OMAP24XX_GPIO_LEVELDETECT1);
+ __raw_writel(old0, bank->base +
+ OMAP24XX_GPIO_LEVELDETECT0);
+ __raw_writel(old1, bank->base +
+ OMAP24XX_GPIO_LEVELDETECT1);
+ } else if (bank->method == METHOD_GPIO_44XX) {
+ old0 = __raw_readl(bank->base +
+ OMAP4_GPIO_LEVELDETECT0);
+ old1 = __raw_readl(bank->base +
+ OMAP4_GPIO_LEVELDETECT1);
+ __raw_writel(old0 | l, bank->base +
+ OMAP4_GPIO_LEVELDETECT0);
+ __raw_writel(old1 | l, bank->base +
+ OMAP4_GPIO_LEVELDETECT1);
+ __raw_writel(old0, bank->base +
+ OMAP4_GPIO_LEVELDETECT0);
+ __raw_writel(old1, bank->base +
+ OMAP4_GPIO_LEVELDETECT1);
+ }
+ }
+}
+
+static int gpio_bank_handle_idle(struct device *dev)
+{
+ struct platform_device *pdev = to_platform_device(dev);
+ struct gpio_bank *bank = &gpio_bank[pdev->id];
+ int j;
+
+ /* If the gpio bank is not used, do nothing */
+ if (!bank->mod_usage || !bank->looses_context)
+ return 0;
+
+ for (j = 0; j < hweight_long(bank->dbck_enable_mask); j++)
+ clk_disable(bank->dbck);
+
+ /* Save the context lost count */
+ bank->ctx_lost_cnt_before =
+ omap_device_get_context_loss_count(pdev);
+
+ if (is_pwrdm_nxt_state_off) {
+ omap_gpio_idle_handle_errata_i468(bank);
+ omap_gpio_save_context(bank);
+ }
+
+ return 0;
+}
+
+static int gpio_bank_handle_resume(struct device *dev)
+{
+ struct platform_device *pdev = to_platform_device(dev);
+ struct gpio_bank *bank = &gpio_bank[pdev->id];
+ u32 ctx_lost_cnt_after;
+ int j;
+
+ /* If the gpio bank is not used, do nothing */
+ if (!bank->mod_usage || !bank->looses_context)
+ return 0;
+
+ for (j = 0; j < hweight_long(bank->dbck_enable_mask); j++)
+ clk_enable(bank->dbck);
+
+ 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) {
+ omap_gpio_resume_handle_errata_i468(bank);
+ omap_gpio_restore_context(bank);
+ }
+
+ return 0;
+}
+#endif
+
#if defined(CONFIG_ARCH_OMAP16XX) || defined(CONFIG_ARCH_OMAP2PLUS)
static int omap_gpio_suspend(struct sys_device *dev, pm_message_t mesg)
{
@@ -1864,183 +2045,26 @@ void omap2_gpio_prepare_for_idle(int off_mode)
{
int i;

+ is_pwrdm_nxt_state_off = 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;
-
- for (j = 0; j < hweight_long(bank->dbck_enable_mask); j++)
- clk_disable(bank->dbck);
-
- if (!off_mode)
- continue;
-
- /*
- * If going to OFF, remove triggering for all
- * non-wakeup GPIOs. Otherwise spurious IRQs will be
- * generated. See OMAP2420 Errata item 1.101.
- */
- if (!(bank->enabled_non_wakeup_gpios))
- goto save_gpio_ctx;
-
- 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);
- } else if (bank->method == METHOD_GPIO_44XX) {
- bank->saved_datain = __raw_readl(bank->base +
- OMAP4_GPIO_DATAIN);
- l1 = __raw_readl(bank->base +
- OMAP4_GPIO_FALLINGDETECT);
- l2 = __raw_readl(bank->base +
- OMAP4_GPIO_RISINGDETECT);
- }
-
- bank->saved_fallingdetect = l1;
- bank->saved_risingdetect = l2;
- l1 &= ~bank->enabled_non_wakeup_gpios;
- l2 &= ~bank->enabled_non_wakeup_gpios;
-
- if (bank->method == METHOD_GPIO_24XX) {
- __raw_writel(l1, bank->base +
- OMAP24XX_GPIO_FALLINGDETECT);
- __raw_writel(l2, bank->base +
- OMAP24XX_GPIO_RISINGDETECT);
- } else if (bank->method == METHOD_GPIO_44XX) {
- __raw_writel(l1, bank->base + OMAP4_GPIO_FALLINGDETECT);
- __raw_writel(l2, bank->base + OMAP4_GPIO_RISINGDETECT);
- }
-
- bank->off_mode_wkup_wa_enabled = true;

-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);
+ gpio_bank_handle_idle(bank->dev);
}
}

void omap2_gpio_resume_after_idle(void)
{
int i;
- u32 ctx_lost_cnt_after;
+
+ is_pwrdm_nxt_state_off = 0;

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);
-
- 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 (!bank->off_mode_wkup_wa_enabled)
- goto restore_gpio_ctx;
-
- if (!(bank->enabled_non_wakeup_gpios))
- goto restore_gpio_ctx;
-
- 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);
- } else if (bank->method == METHOD_GPIO_44XX) {
- __raw_writel(bank->saved_fallingdetect,
- bank->base + OMAP4_GPIO_FALLINGDETECT);
- __raw_writel(bank->saved_risingdetect,
- bank->base + OMAP4_GPIO_RISINGDETECT);
- l = __raw_readl(bank->base + OMAP4_GPIO_DATAIN);
- }
-
- /*
- * 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.
- */
- l ^= bank->saved_datain;
- l &= bank->enabled_non_wakeup_gpios;

- /*
- * No need to generate IRQs for the rising edge for gpio IRQs
- * configured with falling edge only; and vice versa.
- */
- gen0 = l & bank->saved_fallingdetect;
- gen0 &= bank->saved_datain;
-
- gen1 = l & bank->saved_risingdetect;
- gen1 &= ~(bank->saved_datain);
-
- /* FIXME: Consider GPIO IRQs with level detections properly! */
- gen = l & (~(bank->saved_fallingdetect) &
- ~(bank->saved_risingdetect));
- /* Consider all GPIO IRQs needed to be updated */
- gen |= gen0 | gen1;
-
- if (gen) {
- u32 old0, old1;
-
- if (bank->method == METHOD_GPIO_24XX) {
- old0 = __raw_readl(bank->base +
- OMAP24XX_GPIO_LEVELDETECT0);
- old1 = __raw_readl(bank->base +
- OMAP24XX_GPIO_LEVELDETECT1);
- __raw_writel(old0 | gen, bank->base +
- OMAP24XX_GPIO_LEVELDETECT0);
- __raw_writel(old1 | gen, bank->base +
- OMAP24XX_GPIO_LEVELDETECT1);
- __raw_writel(old0, bank->base +
- OMAP24XX_GPIO_LEVELDETECT0);
- __raw_writel(old1, bank->base +
- OMAP24XX_GPIO_LEVELDETECT1);
- } else if (bank->method == METHOD_GPIO_44XX) {
- old0 = __raw_readl(bank->base +
- OMAP4_GPIO_LEVELDETECT0);
- old1 = __raw_readl(bank->base +
- OMAP4_GPIO_LEVELDETECT1);
- __raw_writel(old0 | l, bank->base +
- OMAP4_GPIO_LEVELDETECT0);
- __raw_writel(old1 | l, bank->base +
- OMAP4_GPIO_LEVELDETECT1);
- __raw_writel(old0, bank->base +
- OMAP4_GPIO_LEVELDETECT0);
- __raw_writel(old1, bank->base +
- OMAP4_GPIO_LEVELDETECT1);
- }
- }
-
-restore_gpio_ctx:
- bank->off_mode_wkup_wa_enabled = false;
- omap_gpio_restore_context(bank);
+ gpio_bank_handle_resume(bank->dev);
}
-
}

void omap_gpio_save_context(struct gpio_bank *bank)
--
1.7.1