Merge tag 'omap-for-v4.17/ti-sysc-signed' of ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap into next/soc

Pull "Driver changes for ti-sysc for v4.17" from Tony Lindgren:

This series of changes enables the use device tree based sysconfig
data for ti-sysc driver. As we already have SmartReflex data configured,
we use that as the first driver to enable. To do that in a way where
SmartReflex is not probed twice, we need to prepare the SmartReflex
driver before flipping dts data on for it in the last patch of the
series.

To avoid regressions, we are checking the passed dts data against
existing platform data since we still have it available. Then after the
dts files are converted, we can simply drop the related platform data
at some point in the future.

* tag 'omap-for-v4.17/ti-sysc-signed' of ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap:
  ARM: OMAP2+: Enable ti-sysc to use device tree data for smartreflex
  PM / AVS: SmartReflex: Prepare to use device tree based probing
  ARM: OMAP2+: Try to parse earlycon from parent too
  ARM: OMAP2+: Add checks for device tree based sysconfig data
  ARM: OMAP2+: Add functions to allocate module data from device tree
  bus: ti-sysc: Handle some devices in omap_device compatible way
  bus: ti-sysc: Add support for platform data callbacks
  bus: ti-sysc: Remove unnecessary debugging statements
  bus: ti-sysc: Improve handling for no-reset-on-init and no-idle-on-init
  bus: ti-sysc: Handle stdout-path for debug console
  bus: ti-sysc: Add suspend and resume handling
  bus: ti-sysc: Add fck clock alias for children with notifier_block
  ARM: OMAP2+: Prepare to pass auxdata for smartreflex

1 files changed, 493 insertions, 33 deletions

diff --git a/drivers/bus/ti-sysc.c b/drivers/bus/ti-sysc.c
index cdaeeea7999c..7cd2fd04b212 100644
--- a/drivers/bus/ti-sysc.c
+++ b/drivers/bus/ti-sysc.c
@@ -13,22 +13,20 @@
 
 #include <linux/io.h>
 #include <linux/clk.h>
+#include <linux/clkdev.h>
+#include <linux/delay.h>
 #include <linux/module.h>
 #include <linux/platform_device.h>
+#include <linux/pm_domain.h>
 #include <linux/pm_runtime.h>
 #include <linux/of_address.h>
 #include <linux/of_platform.h>
+#include <linux/slab.h>
+
 #include <linux/platform_data/ti-sysc.h>
 
 #include <dt-bindings/bus/ti-sysc.h>
 
-enum sysc_registers {
-	SYSC_REVISION,
-	SYSC_SYSCONFIG,
-	SYSC_SYSSTATUS,
-	SYSC_MAX_REGS,
-};
-
 static const char * const reg_names[] = { "rev", "sysc", "syss", };
 
 enum sysc_clocks {
@@ -55,6 +53,7 @@ static const char * const clock_names[] = { "fck", "ick", };
  * @cfg: interconnect target module configuration
  * @name: name if available
  * @revision: interconnect target module revision
+ * @needs_resume: runtime resume needed on resume from suspend
  */
 struct sysc {
 	struct device *dev;
@@ -66,8 +65,13 @@ struct sysc {
 	const char *legacy_mode;
 	const struct sysc_capabilities *cap;
 	struct sysc_config cfg;
+	struct ti_sysc_cookie cookie;
 	const char *name;
 	u32 revision;
+	bool enabled;
+	bool needs_resume;
+	bool child_needs_resume;
+	struct delayed_work idle_work;
 };
 
 static u32 sysc_read(struct sysc *ddata, int offset)
@@ -136,9 +140,6 @@ static int sysc_get_clocks(struct sysc *ddata)
 {
 	int i, error;
 
-	if (ddata->legacy_mode)
-		return 0;
-
 	for (i = 0; i < SYSC_MAX_CLOCKS; i++) {
 		error = sysc_get_one_clock(ddata, i);
 		if (error && error != -ENOENT)
@@ -197,12 +198,53 @@ static int sysc_parse_and_check_child_range(struct sysc *ddata)
 	ddata->module_pa = of_translate_address(np, ranges++);
 	ddata->module_size = be32_to_cpup(ranges);
 
-	dev_dbg(ddata->dev, "interconnect target 0x%llx size 0x%x for %pOF\n",
-		ddata->module_pa, ddata->module_size, np);
-
 	return 0;
 }
 
+static struct device_node *stdout_path;
+
+static void sysc_init_stdout_path(struct sysc *ddata)
+{
+	struct device_node *np = NULL;
+	const char *uart;
+
+	if (IS_ERR(stdout_path))
+		return;
+
+	if (stdout_path)
+		return;
+
+	np = of_find_node_by_path("/chosen");
+	if (!np)
+		goto err;
+
+	uart = of_get_property(np, "stdout-path", NULL);
+	if (!uart)
+		goto err;
+
+	np = of_find_node_by_path(uart);
+	if (!np)
+		goto err;
+
+	stdout_path = np;
+
+	return;
+
+err:
+	stdout_path = ERR_PTR(-ENODEV);
+}
+
+static void sysc_check_quirk_stdout(struct sysc *ddata,
+				    struct device_node *np)
+{
+	sysc_init_stdout_path(ddata);
+	if (np != stdout_path)
+		return;
+
+	ddata->cfg.quirks |= SYSC_QUIRK_NO_IDLE_ON_INIT |
+				SYSC_QUIRK_NO_RESET_ON_INIT;
+}
+
 /**
  * sysc_check_one_child - check child configuration
  * @ddata: device driver data
@@ -221,6 +263,8 @@ static int sysc_check_one_child(struct sysc *ddata,
 	if (name)
 		dev_warn(ddata->dev, "really a child ti,hwmods property?");
 
+	sysc_check_quirk_stdout(ddata, np);
+
 	return 0;
 }
 
@@ -246,11 +290,8 @@ static int sysc_check_children(struct sysc *ddata)
  */
 static void sysc_check_quirk_16bit(struct sysc *ddata, struct resource *res)
 {
-	if (resource_size(res) == 8) {
-		dev_dbg(ddata->dev,
-			"enabling 16-bit and clockactivity quirks\n");
+	if (resource_size(res) == 8)
 		ddata->cfg.quirks |= SYSC_QUIRK_16BIT | SYSC_QUIRK_USE_CLOCKACT;
-	}
 }
 
 /**
@@ -276,7 +317,6 @@ static int sysc_parse_one(struct sysc *ddata, enum sysc_registers reg)
 	res = platform_get_resource_byname(to_platform_device(ddata->dev),
 					   IORESOURCE_MEM, name);
 	if (!res) {
-		dev_dbg(ddata->dev, "has no %s register\n", name);
 		ddata->offsets[reg] = -ENODEV;
 
 		return 0;
@@ -437,6 +477,14 @@ static int sysc_show_reg(struct sysc *ddata,
 	return sprintf(bufp, ":%x", ddata->offsets[reg]);
 }
 
+static int sysc_show_name(char *bufp, struct sysc *ddata)
+{
+	if (!ddata->name)
+		return 0;
+
+	return sprintf(bufp, ":%s", ddata->name);
+}
+
 /**
  * sysc_show_registers - show information about interconnect target module
  * @ddata: device driver data
@@ -451,6 +499,7 @@ static void sysc_show_registers(struct sysc *ddata)
 		bufp += sysc_show_reg(ddata, bufp, i);
 
 	bufp += sysc_show_rev(bufp, ddata);
+	bufp += sysc_show_name(bufp, ddata);
 
 	dev_dbg(ddata->dev, "%llx:%x%s\n",
 		ddata->module_pa, ddata->module_size,
@@ -459,33 +508,70 @@ static void sysc_show_registers(struct sysc *ddata)
 
 static int __maybe_unused sysc_runtime_suspend(struct device *dev)
 {
+	struct ti_sysc_platform_data *pdata;
 	struct sysc *ddata;
-	int i;
+	int error = 0, i;
 
 	ddata = dev_get_drvdata(dev);
 
-	if (ddata->legacy_mode)
+	if (!ddata->enabled)
 		return 0;
 
+	if (ddata->legacy_mode) {
+		pdata = dev_get_platdata(ddata->dev);
+		if (!pdata)
+			return 0;
+
+		if (!pdata->idle_module)
+			return -ENODEV;
+
+		error = pdata->idle_module(dev, &ddata->cookie);
+		if (error)
+			dev_err(dev, "%s: could not idle: %i\n",
+				__func__, error);
+
+		goto idled;
+	}
+
 	for (i = 0; i < SYSC_MAX_CLOCKS; i++) {
 		if (IS_ERR_OR_NULL(ddata->clocks[i]))
 			continue;
 		clk_disable(ddata->clocks[i]);
 	}
 
-	return 0;
+idled:
+	ddata->enabled = false;
+
+	return error;
 }
 
 static int __maybe_unused sysc_runtime_resume(struct device *dev)
 {
+	struct ti_sysc_platform_data *pdata;
 	struct sysc *ddata;
-	int i, error;
+	int error = 0, i;
 
 	ddata = dev_get_drvdata(dev);
 
-	if (ddata->legacy_mode)
+	if (ddata->enabled)
 		return 0;
 
+	if (ddata->legacy_mode) {
+		pdata = dev_get_platdata(ddata->dev);
+		if (!pdata)
+			return 0;
+
+		if (!pdata->enable_module)
+			return -ENODEV;
+
+		error = pdata->enable_module(dev, &ddata->cookie);
+		if (error)
+			dev_err(dev, "%s: could not enable: %i\n",
+				__func__, error);
+
+		goto awake;
+	}
+
 	for (i = 0; i < SYSC_MAX_CLOCKS; i++) {
 		if (IS_ERR_OR_NULL(ddata->clocks[i]))
 			continue;
@@ -494,20 +580,136 @@ static int __maybe_unused sysc_runtime_resume(struct device *dev)
 			return error;
 	}
 
+awake:
+	ddata->enabled = true;
+
+	return error;
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int sysc_suspend(struct device *dev)
+{
+	struct sysc *ddata;
+
+	ddata = dev_get_drvdata(dev);
+
+	if (!ddata->enabled)
+		return 0;
+
+	ddata->needs_resume = true;
+
+	return sysc_runtime_suspend(dev);
+}
+
+static int sysc_resume(struct device *dev)
+{
+	struct sysc *ddata;
+
+	ddata = dev_get_drvdata(dev);
+	if (ddata->needs_resume) {
+		ddata->needs_resume = false;
+
+		return sysc_runtime_resume(dev);
+	}
+
 	return 0;
 }
+#endif
 
 static const struct dev_pm_ops sysc_pm_ops = {
+	SET_SYSTEM_SLEEP_PM_OPS(sysc_suspend, sysc_resume)
 	SET_RUNTIME_PM_OPS(sysc_runtime_suspend,
 			   sysc_runtime_resume,
 			   NULL)
 };
 
+/* Module revision register based quirks */
+struct sysc_revision_quirk {
+	const char *name;
+	u32 base;
+	int rev_offset;
+	int sysc_offset;
+	int syss_offset;
+	u32 revision;
+	u32 revision_mask;
+	u32 quirks;
+};
+
+#define SYSC_QUIRK(optname, optbase, optrev, optsysc, optsyss,		\
+		   optrev_val, optrevmask, optquirkmask)		\
+	{								\
+		.name = (optname),					\
+		.base = (optbase),					\
+		.rev_offset = (optrev),					\
+		.sysc_offset = (optsysc),				\
+		.syss_offset = (optsyss),				\
+		.revision = (optrev_val),				\
+		.revision_mask = (optrevmask),				\
+		.quirks = (optquirkmask),				\
+	}
+
+static const struct sysc_revision_quirk sysc_revision_quirks[] = {
+	/* These drivers need to be fixed to not use pm_runtime_irq_safe() */
+	SYSC_QUIRK("gpio", 0, 0, 0x10, 0x114, 0x50600801, 0xffffffff,
+		   SYSC_QUIRK_LEGACY_IDLE),
+	SYSC_QUIRK("mmu", 0, 0, 0x10, 0x14, 0x00000020, 0xffffffff,
+		   SYSC_QUIRK_LEGACY_IDLE),
+	SYSC_QUIRK("mmu", 0, 0, 0x10, 0x14, 0x00000030, 0xffffffff,
+		   SYSC_QUIRK_LEGACY_IDLE),
+	SYSC_QUIRK("sham", 0, 0x100, 0x110, 0x114, 0x40000c03, 0xffffffff,
+		   SYSC_QUIRK_LEGACY_IDLE),
+	SYSC_QUIRK("smartreflex", 0, -1, 0x24, -1, 0x00000000, 0xffffffff,
+		   SYSC_QUIRK_LEGACY_IDLE),
+	SYSC_QUIRK("smartreflex", 0, -1, 0x38, -1, 0x00000000, 0xffffffff,
+		   SYSC_QUIRK_LEGACY_IDLE),
+	SYSC_QUIRK("timer", 0, 0, 0x10, 0x14, 0x00000015, 0xffffffff,
+		   SYSC_QUIRK_LEGACY_IDLE),
+	SYSC_QUIRK("uart", 0, 0x50, 0x54, 0x58, 0x00000052, 0xffffffff,
+		   SYSC_QUIRK_LEGACY_IDLE),
+};
+
+static void sysc_init_revision_quirks(struct sysc *ddata)
+{
+	const struct sysc_revision_quirk *q;
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(sysc_revision_quirks); i++) {
+		q = &sysc_revision_quirks[i];
+
+		if (q->base && q->base != ddata->module_pa)
+			continue;
+
+		if (q->rev_offset >= 0 &&
+		    q->rev_offset != ddata->offsets[SYSC_REVISION])
+			continue;
+
+		if (q->sysc_offset >= 0 &&
+		    q->sysc_offset != ddata->offsets[SYSC_SYSCONFIG])
+			continue;
+
+		if (q->syss_offset >= 0 &&
+		    q->syss_offset != ddata->offsets[SYSC_SYSSTATUS])
+			continue;
+
+		if (q->revision == ddata->revision ||
+		    (q->revision & q->revision_mask) ==
+		    (ddata->revision & q->revision_mask)) {
+			ddata->name = q->name;
+			ddata->cfg.quirks |= q->quirks;
+		}
+	}
+}
+
 /* At this point the module is configured enough to read the revision */
 static int sysc_init_module(struct sysc *ddata)
 {
 	int error;
 
+	if (ddata->cfg.quirks & SYSC_QUIRK_NO_IDLE_ON_INIT) {
+		ddata->revision = sysc_read_revision(ddata);
+		goto rev_quirks;
+	}
+
 	error = pm_runtime_get_sync(ddata->dev);
 	if (error < 0) {
 		pm_runtime_put_noidle(ddata->dev);
@@ -517,6 +719,9 @@ static int sysc_init_module(struct sysc *ddata)
 	ddata->revision = sysc_read_revision(ddata);
 	pm_runtime_put_sync(ddata->dev);
 
+rev_quirks:
+	sysc_init_revision_quirks(ddata);
+
 	return 0;
 }
 
@@ -605,6 +810,196 @@ static int sysc_init_syss_mask(struct sysc *ddata)
 	return 0;
 }
 
+/*
+ * Many child device drivers need to have fck available to get the clock
+ * rate for device internal configuration.
+ */
+static int sysc_child_add_fck(struct sysc *ddata,
+			      struct device *child)
+{
+	struct clk *fck;
+	struct clk_lookup *l;
+	const char *name = clock_names[SYSC_FCK];
+
+	if (IS_ERR_OR_NULL(ddata->clocks[SYSC_FCK]))
+		return 0;
+
+	fck = clk_get(child, name);
+	if (!IS_ERR(fck)) {
+		clk_put(fck);
+
+		return -EEXIST;
+	}
+
+	l = clkdev_create(ddata->clocks[SYSC_FCK], name, dev_name(child));
+
+	return l ? 0 : -ENODEV;
+}
+
+static struct device_type sysc_device_type = {
+};
+
+static struct sysc *sysc_child_to_parent(struct device *dev)
+{
+	struct device *parent = dev->parent;
+
+	if (!parent || parent->type != &sysc_device_type)
+		return NULL;
+
+	return dev_get_drvdata(parent);
+}
+
+static int __maybe_unused sysc_child_runtime_suspend(struct device *dev)
+{
+	struct sysc *ddata;
+	int error;
+
+	ddata = sysc_child_to_parent(dev);
+
+	error = pm_generic_runtime_suspend(dev);
+	if (error)
+		return error;
+
+	if (!ddata->enabled)
+		return 0;
+
+	return sysc_runtime_suspend(ddata->dev);
+}
+
+static int __maybe_unused sysc_child_runtime_resume(struct device *dev)
+{
+	struct sysc *ddata;
+	int error;
+
+	ddata = sysc_child_to_parent(dev);
+
+	if (!ddata->enabled) {
+		error = sysc_runtime_resume(ddata->dev);
+		if (error < 0)
+			dev_err(ddata->dev,
+				"%s error: %i\n", __func__, error);
+	}
+
+	return pm_generic_runtime_resume(dev);
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int sysc_child_suspend_noirq(struct device *dev)
+{
+	struct sysc *ddata;
+	int error;
+
+	ddata = sysc_child_to_parent(dev);
+
+	error = pm_generic_suspend_noirq(dev);
+	if (error)
+		return error;
+
+	if (!pm_runtime_status_suspended(dev)) {
+		error = pm_generic_runtime_suspend(dev);
+		if (error)
+			return error;
+
+		error = sysc_runtime_suspend(ddata->dev);
+		if (error)
+			return error;
+
+		ddata->child_needs_resume = true;
+	}
+
+	return 0;
+}
+
+static int sysc_child_resume_noirq(struct device *dev)
+{
+	struct sysc *ddata;
+	int error;
+
+	ddata = sysc_child_to_parent(dev);
+
+	if (ddata->child_needs_resume) {
+		ddata->child_needs_resume = false;
+
+		error = sysc_runtime_resume(ddata->dev);
+		if (error)
+			dev_err(ddata->dev,
+				"%s runtime resume error: %i\n",
+				__func__, error);
+
+		error = pm_generic_runtime_resume(dev);
+		if (error)
+			dev_err(ddata->dev,
+				"%s generic runtime resume: %i\n",
+				__func__, error);
+	}
+
+	return pm_generic_resume_noirq(dev);
+}
+#endif
+
+struct dev_pm_domain sysc_child_pm_domain = {
+	.ops = {
+		SET_RUNTIME_PM_OPS(sysc_child_runtime_suspend,
+				   sysc_child_runtime_resume,
+				   NULL)
+		USE_PLATFORM_PM_SLEEP_OPS
+		SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(sysc_child_suspend_noirq,
+					      sysc_child_resume_noirq)
+	}
+};
+
+/**
+ * sysc_legacy_idle_quirk - handle children in omap_device compatible way
+ * @ddata: device driver data
+ * @child: child device driver
+ *
+ * Allow idle for child devices as done with _od_runtime_suspend().
+ * Otherwise many child devices will not idle because of the permanent
+ * parent usecount set in pm_runtime_irq_safe().
+ *
+ * Note that the long term solution is to just modify the child device
+ * drivers to not set pm_runtime_irq_safe() and then this can be just
+ * dropped.
+ */
+static void sysc_legacy_idle_quirk(struct sysc *ddata, struct device *child)
+{
+	if (!ddata->legacy_mode)
+		return;
+
+	if (ddata->cfg.quirks & SYSC_QUIRK_LEGACY_IDLE)
+		dev_pm_domain_set(child, &sysc_child_pm_domain);
+}
+
+static int sysc_notifier_call(struct notifier_block *nb,
+			      unsigned long event, void *device)
+{
+	struct device *dev = device;
+	struct sysc *ddata;
+	int error;
+
+	ddata = sysc_child_to_parent(dev);
+	if (!ddata)
+		return NOTIFY_DONE;
+
+	switch (event) {
+	case BUS_NOTIFY_ADD_DEVICE:
+		error = sysc_child_add_fck(ddata, dev);
+		if (error && error != -EEXIST)
+			dev_warn(ddata->dev, "could not add %s fck: %i\n",
+				 dev_name(dev), error);
+		sysc_legacy_idle_quirk(ddata, dev);
+		break;
+	default:
+		break;
+	}
+
+	return NOTIFY_DONE;
+}
+
+static struct notifier_block sysc_nb = {
+	.notifier_call = sysc_notifier_call,
+};
+
 /* Device tree configured quirks */
 struct sysc_dts_quirk {
 	const char *name;
@@ -797,7 +1192,8 @@ static const struct sysc_capabilities sysc_34xx_sr = {
 	.type = TI_SYSC_OMAP34XX_SR,
 	.sysc_mask = SYSC_OMAP2_CLOCKACTIVITY,
 	.regbits = &sysc_regbits_omap34xx_sr,
-	.mod_quirks = SYSC_QUIRK_USE_CLOCKACT | SYSC_QUIRK_UNCACHED,
+	.mod_quirks = SYSC_QUIRK_USE_CLOCKACT | SYSC_QUIRK_UNCACHED |
+		      SYSC_QUIRK_LEGACY_IDLE,
 };
 
 /*
@@ -818,12 +1214,13 @@ static const struct sysc_capabilities sysc_36xx_sr = {
 	.type = TI_SYSC_OMAP36XX_SR,
 	.sysc_mask = SYSC_OMAP3_SR_ENAWAKEUP,
 	.regbits = &sysc_regbits_omap36xx_sr,
-	.mod_quirks = SYSC_QUIRK_UNCACHED,
+	.mod_quirks = SYSC_QUIRK_UNCACHED | SYSC_QUIRK_LEGACY_IDLE,
 };
 
 static const struct sysc_capabilities sysc_omap4_sr = {
 	.type = TI_SYSC_OMAP4_SR,
 	.regbits = &sysc_regbits_omap36xx_sr,
+	.mod_quirks = SYSC_QUIRK_LEGACY_IDLE,
 };
 
 /*
@@ -865,6 +1262,33 @@ static const struct sysc_capabilities sysc_omap4_usb_host_fs = {
 	.regbits = &sysc_regbits_omap4_usb_host_fs,
 };
 
+static int sysc_init_pdata(struct sysc *ddata)
+{
+	struct ti_sysc_platform_data *pdata = dev_get_platdata(ddata->dev);
+	struct ti_sysc_module_data mdata;
+	int error = 0;
+
+	if (!pdata || !ddata->legacy_mode)
+		return 0;
+
+	mdata.name = ddata->legacy_mode;
+	mdata.module_pa = ddata->module_pa;
+	mdata.module_size = ddata->module_size;
+	mdata.offsets = ddata->offsets;
+	mdata.nr_offsets = SYSC_MAX_REGS;
+	mdata.cap = ddata->cap;
+	mdata.cfg = &ddata->cfg;
+
+	if (!pdata->init_module)
+		return -ENODEV;
+
+	error = pdata->init_module(ddata->dev, &mdata, &ddata->cookie);
+	if (error == -EEXIST)
+		error = 0;
+
+	return error;
+}
+
 static int sysc_init_match(struct sysc *ddata)
 {
 	const struct sysc_capabilities *cap;
@@ -880,8 +1304,19 @@ static int sysc_init_match(struct sysc *ddata)
 	return 0;
 }
 
+static void ti_sysc_idle(struct work_struct *work)
+{
+	struct sysc *ddata;
+
+	ddata = container_of(work, struct sysc, idle_work.work);
+
+	if (pm_runtime_active(ddata->dev))
+		pm_runtime_put_sync(ddata->dev);
+}
+
 static int sysc_probe(struct platform_device *pdev)
 {
+	struct ti_sysc_platform_data *pdata = dev_get_platdata(&pdev->dev);
 	struct sysc *ddata;
 	int error;
 
@@ -920,6 +1355,10 @@ static int sysc_probe(struct platform_device *pdev)
 	if (error)
 		goto unprepare;
 
+	error = sysc_init_pdata(ddata);
+	if (error)
+		goto unprepare;
+
 	pm_runtime_enable(ddata->dev);
 
 	error = sysc_init_module(ddata);
@@ -933,22 +1372,28 @@ static int sysc_probe(struct platform_device *pdev)
 		goto unprepare;
 	}
 
-	pm_runtime_use_autosuspend(ddata->dev);
-
 	sysc_show_registers(ddata);
 
+	ddata->dev->type = &sysc_device_type;
 	error = of_platform_populate(ddata->dev->of_node,
-				     NULL, NULL, ddata->dev);
+				     NULL, pdata ? pdata->auxdata : NULL,
+				     ddata->dev);
 	if (error)
 		goto err;
 
-	pm_runtime_mark_last_busy(ddata->dev);
-	pm_runtime_put_autosuspend(ddata->dev);
+	INIT_DELAYED_WORK(&ddata->idle_work, ti_sysc_idle);
+
+	/* At least earlycon won't survive without deferred idle */
+	if (ddata->cfg.quirks & (SYSC_QUIRK_NO_IDLE_ON_INIT |
+				 SYSC_QUIRK_NO_RESET_ON_INIT)) {
+		schedule_delayed_work(&ddata->idle_work, 3000);
+	} else {
+		pm_runtime_put(&pdev->dev);
+	}
 
 	return 0;
 
 err:
-	pm_runtime_dont_use_autosuspend(&pdev->dev);
 	pm_runtime_put_sync(&pdev->dev);
 	pm_runtime_disable(&pdev->dev);
 unprepare:
@@ -962,6 +1407,8 @@ static int sysc_remove(struct platform_device *pdev)
 	struct sysc *ddata = platform_get_drvdata(pdev);
 	int error;
 
+	cancel_delayed_work_sync(&ddata->idle_work);
+
 	error = pm_runtime_get_sync(ddata->dev);
 	if (error < 0) {
 		pm_runtime_put_noidle(ddata->dev);
@@ -971,7 +1418,6 @@ static int sysc_remove(struct platform_device *pdev)
 
 	of_platform_depopulate(&pdev->dev);
 
-	pm_runtime_dont_use_autosuspend(&pdev->dev);
 	pm_runtime_put_sync(&pdev->dev);
 	pm_runtime_disable(&pdev->dev);
 
@@ -1008,7 +1454,21 @@ static struct platform_driver sysc_driver = {
 		.pm = &sysc_pm_ops,
 	},
 };
-module_platform_driver(sysc_driver);
+
+static int __init sysc_init(void)
+{
+	bus_register_notifier(&platform_bus_type, &sysc_nb);
+
+	return platform_driver_register(&sysc_driver);
+}
+module_init(sysc_init);
+
+static void __exit sysc_exit(void)
+{
+	bus_unregister_notifier(&platform_bus_type, &sysc_nb);
+	platform_driver_unregister(&sysc_driver);
+}
+module_exit(sysc_exit);
 
 MODULE_DESCRIPTION("TI sysc interconnect target driver");
 MODULE_LICENSE("GPL v2");