ARM: OMAP: 34xx specific check wether any fck is active before entering sleep

We cannot enter sleep_while_idle if some functional clocks are
active. Add a check for enabled functional clocks for 34xx.

Note that this workaround could be behind CONFIG_PM_DEBUG
option when all drivers are configuring their sysconfig
registers properly and using their clocks properly.
Signed-off-by: Jouni Hogander <jouni.hogander@nokia.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>

arch/arm/mach-omap2/pm34xx.c

@@ -174,10 +174,47 @@ static void omap_sram_idle(void)
 	omap2_gpio_resume_after_retention();
 }
 
+/*
+ * Check if functional clocks are enabled before entering
+ * sleep. This function could be behind CONFIG_PM_DEBUG
+ * when all drivers are configuring their sysconfig registers
+ * properly and using their clocks properly.
+ */
+static int omap3_fclks_active(void)
+{
+	u32 fck_core1 = 0, fck_core3 = 0, fck_sgx = 0, fck_dss = 0,
+		fck_cam = 0, fck_per = 0, fck_usbhost = 0;
+
+	fck_core1 = cm_read_mod_reg(CORE_MOD,
+				    CM_FCLKEN1);
+	if (is_sil_rev_greater_than(OMAP3430_REV_ES1_0)) {
+		fck_core3 = cm_read_mod_reg(CORE_MOD,
+					    OMAP3430ES2_CM_FCLKEN3);
+		fck_sgx = cm_read_mod_reg(OMAP3430ES2_SGX_MOD,
+					  CM_FCLKEN);
+		fck_usbhost = cm_read_mod_reg(OMAP3430ES2_USBHOST_MOD,
+					      CM_FCLKEN);
+	} else
+		fck_sgx = cm_read_mod_reg(GFX_MOD,
+					  OMAP3430ES2_CM_FCLKEN3);
+	fck_dss = cm_read_mod_reg(OMAP3430_DSS_MOD,
+				  CM_FCLKEN);
+	fck_cam = cm_read_mod_reg(OMAP3430_CAM_MOD,
+				  CM_FCLKEN);
+	fck_per = cm_read_mod_reg(OMAP3430_PER_MOD,
+				  CM_FCLKEN);
+	if (fck_core1 | fck_core3 | fck_sgx | fck_dss |
+	    fck_cam | fck_per | fck_usbhost)
+		return 1;
+	return 0;
+}
+
 static int omap3_can_sleep(void)
 {
 	if (!enable_dyn_sleep)
 		return 0;
+	if (omap3_fclks_active())
+		return 0;
 	if (atomic_read(&sleep_block) > 0)
 		return 0;
 	return 1;