PM: AVS: smartreflex Move driver to soc specific drivers

The avs drivers are all SoC specific drivers that doesn't share any code.
Instead they are located in a directory, mostly to keep similar
functionality together. From a maintenance point of view, it makes better
sense to collect SoC specific drivers like these, into the SoC specific
directories.

Therefore, let's move the smartreflex driver for OMAP to the ti directory.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Nishanth Menon <nm@ti.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

2 files changed, 1046 insertions, 0 deletions

diff --git a/drivers/soc/ti/Makefile b/drivers/soc/ti/Makefile
index 1110e5c98685..5463431ec96c 100644
--- a/drivers/soc/ti/Makefile
+++ b/drivers/soc/ti/Makefile
@@ -12,3 +12,4 @@ obj-$(CONFIG_TI_SCI_PM_DOMAINS)		+= ti_sci_pm_domains.o
 obj-$(CONFIG_TI_SCI_INTA_MSI_DOMAIN)	+= ti_sci_inta_msi.o
 obj-$(CONFIG_TI_K3_RINGACC)		+= k3-ringacc.o
 obj-$(CONFIG_TI_K3_SOCINFO)		+= k3-socinfo.o
+obj-$(CONFIG_POWER_AVS_OMAP)		+= smartreflex.o
diff --git a/drivers/soc/ti/smartreflex.c b/drivers/soc/ti/smartreflex.c
new file mode 100644
index 000000000000..5376f3d22f31
--- /dev/null
+++ b/drivers/soc/ti/smartreflex.c
@@ -0,0 +1,1045 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * OMAP SmartReflex Voltage Control
+ *
+ * Author: Thara Gopinath	<thara@ti.com>
+ *
+ * Copyright (C) 2012 Texas Instruments, Inc.
+ * Thara Gopinath <thara@ti.com>
+ *
+ * Copyright (C) 2008 Nokia Corporation
+ * Kalle Jokiniemi
+ *
+ * Copyright (C) 2007 Texas Instruments, Inc.
+ * Lesly A M <x0080970@ti.com>
+ */
+
+#include <linux/module.h>
+#include <linux/mod_devicetable.h>
+#include <linux/interrupt.h>
+#include <linux/clk.h>
+#include <linux/io.h>
+#include <linux/debugfs.h>
+#include <linux/delay.h>
+#include <linux/slab.h>
+#include <linux/pm_runtime.h>
+#include <linux/power/smartreflex.h>
+
+#define DRIVER_NAME	"smartreflex"
+#define SMARTREFLEX_NAME_LEN	32
+#define NVALUE_NAME_LEN		40
+#define SR_DISABLE_TIMEOUT	200
+
+/* sr_list contains all the instances of smartreflex module */
+static LIST_HEAD(sr_list);
+
+static struct omap_sr_class_data *sr_class;
+static struct dentry		*sr_dbg_dir;
+
+static inline void sr_write_reg(struct omap_sr *sr, unsigned offset, u32 value)
+{
+	__raw_writel(value, (sr->base + offset));
+}
+
+static inline void sr_modify_reg(struct omap_sr *sr, unsigned offset, u32 mask,
+					u32 value)
+{
+	u32 reg_val;
+
+	/*
+	 * Smartreflex error config register is special as it contains
+	 * certain status bits which if written a 1 into means a clear
+	 * of those bits. So in order to make sure no accidental write of
+	 * 1 happens to those status bits, do a clear of them in the read
+	 * value. This mean this API doesn't rewrite values in these bits
+	 * if they are currently set, but does allow the caller to write
+	 * those bits.
+	 */
+	if (sr->ip_type == SR_TYPE_V1 && offset == ERRCONFIG_V1)
+		mask |= ERRCONFIG_STATUS_V1_MASK;
+	else if (sr->ip_type == SR_TYPE_V2 && offset == ERRCONFIG_V2)
+		mask |= ERRCONFIG_VPBOUNDINTST_V2;
+
+	reg_val = __raw_readl(sr->base + offset);
+	reg_val &= ~mask;
+
+	value &= mask;
+
+	reg_val |= value;
+
+	__raw_writel(reg_val, (sr->base + offset));
+}
+
+static inline u32 sr_read_reg(struct omap_sr *sr, unsigned offset)
+{
+	return __raw_readl(sr->base + offset);
+}
+
+static struct omap_sr *_sr_lookup(struct voltagedomain *voltdm)
+{
+	struct omap_sr *sr_info;
+
+	if (!voltdm) {
+		pr_err("%s: Null voltage domain passed!\n", __func__);
+		return ERR_PTR(-EINVAL);
+	}
+
+	list_for_each_entry(sr_info, &sr_list, node) {
+		if (voltdm == sr_info->voltdm)
+			return sr_info;
+	}
+
+	return ERR_PTR(-ENODATA);
+}
+
+static irqreturn_t sr_interrupt(int irq, void *data)
+{
+	struct omap_sr *sr_info = data;
+	u32 status = 0;
+
+	switch (sr_info->ip_type) {
+	case SR_TYPE_V1:
+		/* Read the status bits */
+		status = sr_read_reg(sr_info, ERRCONFIG_V1);
+
+		/* Clear them by writing back */
+		sr_write_reg(sr_info, ERRCONFIG_V1, status);
+		break;
+	case SR_TYPE_V2:
+		/* Read the status bits */
+		status = sr_read_reg(sr_info, IRQSTATUS);
+
+		/* Clear them by writing back */
+		sr_write_reg(sr_info, IRQSTATUS, status);
+		break;
+	default:
+		dev_err(&sr_info->pdev->dev, "UNKNOWN IP type %d\n",
+			sr_info->ip_type);
+		return IRQ_NONE;
+	}
+
+	if (sr_class->notify)
+		sr_class->notify(sr_info, status);
+
+	return IRQ_HANDLED;
+}
+
+static void sr_set_clk_length(struct omap_sr *sr)
+{
+	struct clk *fck;
+	u32 fclk_speed;
+
+	/* Try interconnect target module fck first if it already exists */
+	fck = clk_get(sr->pdev->dev.parent, "fck");
+	if (IS_ERR(fck)) {
+		fck = clk_get(&sr->pdev->dev, "fck");
+		if (IS_ERR(fck)) {
+			dev_err(&sr->pdev->dev,
+				"%s: unable to get fck for device %s\n",
+				__func__, dev_name(&sr->pdev->dev));
+			return;
+		}
+	}
+
+	fclk_speed = clk_get_rate(fck);
+	clk_put(fck);
+
+	switch (fclk_speed) {
+	case 12000000:
+		sr->clk_length = SRCLKLENGTH_12MHZ_SYSCLK;
+		break;
+	case 13000000:
+		sr->clk_length = SRCLKLENGTH_13MHZ_SYSCLK;
+		break;
+	case 19200000:
+		sr->clk_length = SRCLKLENGTH_19MHZ_SYSCLK;
+		break;
+	case 26000000:
+		sr->clk_length = SRCLKLENGTH_26MHZ_SYSCLK;
+		break;
+	case 38400000:
+		sr->clk_length = SRCLKLENGTH_38MHZ_SYSCLK;
+		break;
+	default:
+		dev_err(&sr->pdev->dev, "%s: Invalid fclk rate: %d\n",
+			__func__, fclk_speed);
+		break;
+	}
+}
+
+static void sr_start_vddautocomp(struct omap_sr *sr)
+{
+	if (!sr_class || !(sr_class->enable) || !(sr_class->configure)) {
+		dev_warn(&sr->pdev->dev,
+			 "%s: smartreflex class driver not registered\n",
+			 __func__);
+		return;
+	}
+
+	if (!sr_class->enable(sr))
+		sr->autocomp_active = true;
+}
+
+static void sr_stop_vddautocomp(struct omap_sr *sr)
+{
+	if (!sr_class || !(sr_class->disable)) {
+		dev_warn(&sr->pdev->dev,
+			 "%s: smartreflex class driver not registered\n",
+			 __func__);
+		return;
+	}
+
+	if (sr->autocomp_active) {
+		sr_class->disable(sr, 1);
+		sr->autocomp_active = false;
+	}
+}
+
+/*
+ * This function handles the initializations which have to be done
+ * only when both sr device and class driver regiter has
+ * completed. This will be attempted to be called from both sr class
+ * driver register and sr device intializtion API's. Only one call
+ * will ultimately succeed.
+ *
+ * Currently this function registers interrupt handler for a particular SR
+ * if smartreflex class driver is already registered and has
+ * requested for interrupts and the SR interrupt line in present.
+ */
+static int sr_late_init(struct omap_sr *sr_info)
+{
+	struct omap_sr_data *pdata = sr_info->pdev->dev.platform_data;
+	int ret = 0;
+
+	if (sr_class->notify && sr_class->notify_flags && sr_info->irq) {
+		ret = devm_request_irq(&sr_info->pdev->dev, sr_info->irq,
+				       sr_interrupt, 0, sr_info->name, sr_info);
+		if (ret)
+			goto error;
+		disable_irq(sr_info->irq);
+	}
+
+	if (pdata && pdata->enable_on_init)
+		sr_start_vddautocomp(sr_info);
+
+	return ret;
+
+error:
+	list_del(&sr_info->node);
+	dev_err(&sr_info->pdev->dev, "%s: ERROR in registering interrupt handler. Smartreflex will not function as desired\n",
+		__func__);
+
+	return ret;
+}
+
+static void sr_v1_disable(struct omap_sr *sr)
+{
+	int timeout = 0;
+	int errconf_val = ERRCONFIG_MCUACCUMINTST | ERRCONFIG_MCUVALIDINTST |
+			ERRCONFIG_MCUBOUNDINTST;
+
+	/* Enable MCUDisableAcknowledge interrupt */
+	sr_modify_reg(sr, ERRCONFIG_V1,
+			ERRCONFIG_MCUDISACKINTEN, ERRCONFIG_MCUDISACKINTEN);
+
+	/* SRCONFIG - disable SR */
+	sr_modify_reg(sr, SRCONFIG, SRCONFIG_SRENABLE, 0x0);
+
+	/* Disable all other SR interrupts and clear the status as needed */
+	if (sr_read_reg(sr, ERRCONFIG_V1) & ERRCONFIG_VPBOUNDINTST_V1)
+		errconf_val |= ERRCONFIG_VPBOUNDINTST_V1;
+	sr_modify_reg(sr, ERRCONFIG_V1,
+			(ERRCONFIG_MCUACCUMINTEN | ERRCONFIG_MCUVALIDINTEN |
+			ERRCONFIG_MCUBOUNDINTEN | ERRCONFIG_VPBOUNDINTEN_V1),
+			errconf_val);
+
+	/*
+	 * Wait for SR to be disabled.
+	 * wait until ERRCONFIG.MCUDISACKINTST = 1. Typical latency is 1us.
+	 */
+	sr_test_cond_timeout((sr_read_reg(sr, ERRCONFIG_V1) &
+			     ERRCONFIG_MCUDISACKINTST), SR_DISABLE_TIMEOUT,
+			     timeout);
+
+	if (timeout >= SR_DISABLE_TIMEOUT)
+		dev_warn(&sr->pdev->dev, "%s: Smartreflex disable timedout\n",
+			 __func__);
+
+	/* Disable MCUDisableAcknowledge interrupt & clear pending interrupt */
+	sr_modify_reg(sr, ERRCONFIG_V1, ERRCONFIG_MCUDISACKINTEN,
+			ERRCONFIG_MCUDISACKINTST);
+}
+
+static void sr_v2_disable(struct omap_sr *sr)
+{
+	int timeout = 0;
+
+	/* Enable MCUDisableAcknowledge interrupt */
+	sr_write_reg(sr, IRQENABLE_SET, IRQENABLE_MCUDISABLEACKINT);
+
+	/* SRCONFIG - disable SR */
+	sr_modify_reg(sr, SRCONFIG, SRCONFIG_SRENABLE, 0x0);
+
+	/*
+	 * Disable all other SR interrupts and clear the status
+	 * write to status register ONLY on need basis - only if status
+	 * is set.
+	 */
+	if (sr_read_reg(sr, ERRCONFIG_V2) & ERRCONFIG_VPBOUNDINTST_V2)
+		sr_modify_reg(sr, ERRCONFIG_V2, ERRCONFIG_VPBOUNDINTEN_V2,
+			ERRCONFIG_VPBOUNDINTST_V2);
+	else
+		sr_modify_reg(sr, ERRCONFIG_V2, ERRCONFIG_VPBOUNDINTEN_V2,
+				0x0);
+	sr_write_reg(sr, IRQENABLE_CLR, (IRQENABLE_MCUACCUMINT |
+			IRQENABLE_MCUVALIDINT |
+			IRQENABLE_MCUBOUNDSINT));
+	sr_write_reg(sr, IRQSTATUS, (IRQSTATUS_MCUACCUMINT |
+			IRQSTATUS_MCVALIDINT |
+			IRQSTATUS_MCBOUNDSINT));
+
+	/*
+	 * Wait for SR to be disabled.
+	 * wait until IRQSTATUS.MCUDISACKINTST = 1. Typical latency is 1us.
+	 */
+	sr_test_cond_timeout((sr_read_reg(sr, IRQSTATUS) &
+			     IRQSTATUS_MCUDISABLEACKINT), SR_DISABLE_TIMEOUT,
+			     timeout);
+
+	if (timeout >= SR_DISABLE_TIMEOUT)
+		dev_warn(&sr->pdev->dev, "%s: Smartreflex disable timedout\n",
+			 __func__);
+
+	/* Disable MCUDisableAcknowledge interrupt & clear pending interrupt */
+	sr_write_reg(sr, IRQENABLE_CLR, IRQENABLE_MCUDISABLEACKINT);
+	sr_write_reg(sr, IRQSTATUS, IRQSTATUS_MCUDISABLEACKINT);
+}
+
+static struct omap_sr_nvalue_table *sr_retrieve_nvalue_row(
+				struct omap_sr *sr, u32 efuse_offs)
+{
+	int i;
+
+	if (!sr->nvalue_table) {
+		dev_warn(&sr->pdev->dev, "%s: Missing ntarget value table\n",
+			 __func__);
+		return NULL;
+	}
+
+	for (i = 0; i < sr->nvalue_count; i++) {
+		if (sr->nvalue_table[i].efuse_offs == efuse_offs)
+			return &sr->nvalue_table[i];
+	}
+
+	return NULL;
+}
+
+/* Public Functions */
+
+/**
+ * sr_configure_errgen() - Configures the SmartReflex to perform AVS using the
+ *			 error generator module.
+ * @sr:			SR module to be configured.
+ *
+ * This API is to be called from the smartreflex class driver to
+ * configure the error generator module inside the smartreflex module.
+ * SR settings if using the ERROR module inside Smartreflex.
+ * SR CLASS 3 by default uses only the ERROR module where as
+ * SR CLASS 2 can choose between ERROR module and MINMAXAVG
+ * module. Returns 0 on success and error value in case of failure.
+ */
+int sr_configure_errgen(struct omap_sr *sr)
+{
+	u32 sr_config, sr_errconfig, errconfig_offs;
+	u32 vpboundint_en, vpboundint_st;
+	u32 senp_en = 0, senn_en = 0;
+	u8 senp_shift, senn_shift;
+
+	if (!sr) {
+		pr_warn("%s: NULL omap_sr from %pS\n",
+			__func__, (void *)_RET_IP_);
+		return -EINVAL;
+	}
+
+	if (!sr->clk_length)
+		sr_set_clk_length(sr);
+
+	senp_en = sr->senp_mod;
+	senn_en = sr->senn_mod;
+
+	sr_config = (sr->clk_length << SRCONFIG_SRCLKLENGTH_SHIFT) |
+		SRCONFIG_SENENABLE | SRCONFIG_ERRGEN_EN;
+
+	switch (sr->ip_type) {
+	case SR_TYPE_V1:
+		sr_config |= SRCONFIG_DELAYCTRL;
+		senn_shift = SRCONFIG_SENNENABLE_V1_SHIFT;
+		senp_shift = SRCONFIG_SENPENABLE_V1_SHIFT;
+		errconfig_offs = ERRCONFIG_V1;
+		vpboundint_en = ERRCONFIG_VPBOUNDINTEN_V1;
+		vpboundint_st = ERRCONFIG_VPBOUNDINTST_V1;
+		break;
+	case SR_TYPE_V2:
+		senn_shift = SRCONFIG_SENNENABLE_V2_SHIFT;
+		senp_shift = SRCONFIG_SENPENABLE_V2_SHIFT;
+		errconfig_offs = ERRCONFIG_V2;
+		vpboundint_en = ERRCONFIG_VPBOUNDINTEN_V2;
+		vpboundint_st = ERRCONFIG_VPBOUNDINTST_V2;
+		break;
+	default:
+		dev_err(&sr->pdev->dev, "%s: Trying to Configure smartreflex module without specifying the ip\n",
+			__func__);
+		return -EINVAL;
+	}
+
+	sr_config |= ((senn_en << senn_shift) | (senp_en << senp_shift));
+	sr_write_reg(sr, SRCONFIG, sr_config);
+	sr_errconfig = (sr->err_weight << ERRCONFIG_ERRWEIGHT_SHIFT) |
+		(sr->err_maxlimit << ERRCONFIG_ERRMAXLIMIT_SHIFT) |
+		(sr->err_minlimit <<  ERRCONFIG_ERRMINLIMIT_SHIFT);
+	sr_modify_reg(sr, errconfig_offs, (SR_ERRWEIGHT_MASK |
+		SR_ERRMAXLIMIT_MASK | SR_ERRMINLIMIT_MASK),
+		sr_errconfig);
+
+	/* Enabling the interrupts if the ERROR module is used */
+	sr_modify_reg(sr, errconfig_offs, (vpboundint_en | vpboundint_st),
+		      vpboundint_en);
+
+	return 0;
+}
+
+/**
+ * sr_disable_errgen() - Disables SmartReflex AVS module's errgen component
+ * @sr:			SR module to be configured.
+ *
+ * This API is to be called from the smartreflex class driver to
+ * disable the error generator module inside the smartreflex module.
+ *
+ * Returns 0 on success and error value in case of failure.
+ */
+int sr_disable_errgen(struct omap_sr *sr)
+{
+	u32 errconfig_offs;
+	u32 vpboundint_en, vpboundint_st;
+
+	if (!sr) {
+		pr_warn("%s: NULL omap_sr from %pS\n",
+			__func__, (void *)_RET_IP_);
+		return -EINVAL;
+	}
+
+	switch (sr->ip_type) {
+	case SR_TYPE_V1:
+		errconfig_offs = ERRCONFIG_V1;
+		vpboundint_en = ERRCONFIG_VPBOUNDINTEN_V1;
+		vpboundint_st = ERRCONFIG_VPBOUNDINTST_V1;
+		break;
+	case SR_TYPE_V2:
+		errconfig_offs = ERRCONFIG_V2;
+		vpboundint_en = ERRCONFIG_VPBOUNDINTEN_V2;
+		vpboundint_st = ERRCONFIG_VPBOUNDINTST_V2;
+		break;
+	default:
+		dev_err(&sr->pdev->dev, "%s: Trying to Configure smartreflex module without specifying the ip\n",
+			__func__);
+		return -EINVAL;
+	}
+
+	/* Disable the Sensor and errorgen */
+	sr_modify_reg(sr, SRCONFIG, SRCONFIG_SENENABLE | SRCONFIG_ERRGEN_EN, 0);
+
+	/*
+	 * Disable the interrupts of ERROR module
+	 * NOTE: modify is a read, modify,write - an implicit OCP barrier
+	 * which is required is present here - sequencing is critical
+	 * at this point (after errgen is disabled, vpboundint disable)
+	 */
+	sr_modify_reg(sr, errconfig_offs, vpboundint_en | vpboundint_st, 0);
+
+	return 0;
+}
+
+/**
+ * sr_configure_minmax() - Configures the SmartReflex to perform AVS using the
+ *			 minmaxavg module.
+ * @sr:			SR module to be configured.
+ *
+ * This API is to be called from the smartreflex class driver to
+ * configure the minmaxavg module inside the smartreflex module.
+ * SR settings if using the ERROR module inside Smartreflex.
+ * SR CLASS 3 by default uses only the ERROR module where as
+ * SR CLASS 2 can choose between ERROR module and MINMAXAVG
+ * module. Returns 0 on success and error value in case of failure.
+ */
+int sr_configure_minmax(struct omap_sr *sr)
+{
+	u32 sr_config, sr_avgwt;
+	u32 senp_en = 0, senn_en = 0;
+	u8 senp_shift, senn_shift;
+
+	if (!sr) {
+		pr_warn("%s: NULL omap_sr from %pS\n",
+			__func__, (void *)_RET_IP_);
+		return -EINVAL;
+	}
+
+	if (!sr->clk_length)
+		sr_set_clk_length(sr);
+
+	senp_en = sr->senp_mod;
+	senn_en = sr->senn_mod;
+
+	sr_config = (sr->clk_length << SRCONFIG_SRCLKLENGTH_SHIFT) |
+		SRCONFIG_SENENABLE |
+		(sr->accum_data << SRCONFIG_ACCUMDATA_SHIFT);
+
+	switch (sr->ip_type) {
+	case SR_TYPE_V1:
+		sr_config |= SRCONFIG_DELAYCTRL;
+		senn_shift = SRCONFIG_SENNENABLE_V1_SHIFT;
+		senp_shift = SRCONFIG_SENPENABLE_V1_SHIFT;
+		break;
+	case SR_TYPE_V2:
+		senn_shift = SRCONFIG_SENNENABLE_V2_SHIFT;
+		senp_shift = SRCONFIG_SENPENABLE_V2_SHIFT;
+		break;
+	default:
+		dev_err(&sr->pdev->dev, "%s: Trying to Configure smartreflex module without specifying the ip\n",
+			__func__);
+		return -EINVAL;
+	}
+
+	sr_config |= ((senn_en << senn_shift) | (senp_en << senp_shift));
+	sr_write_reg(sr, SRCONFIG, sr_config);
+	sr_avgwt = (sr->senp_avgweight << AVGWEIGHT_SENPAVGWEIGHT_SHIFT) |
+		(sr->senn_avgweight << AVGWEIGHT_SENNAVGWEIGHT_SHIFT);
+	sr_write_reg(sr, AVGWEIGHT, sr_avgwt);
+
+	/*
+	 * Enabling the interrupts if MINMAXAVG module is used.
+	 * TODO: check if all the interrupts are mandatory
+	 */
+	switch (sr->ip_type) {
+	case SR_TYPE_V1:
+		sr_modify_reg(sr, ERRCONFIG_V1,
+			(ERRCONFIG_MCUACCUMINTEN | ERRCONFIG_MCUVALIDINTEN |
+			ERRCONFIG_MCUBOUNDINTEN),
+			(ERRCONFIG_MCUACCUMINTEN | ERRCONFIG_MCUACCUMINTST |
+			 ERRCONFIG_MCUVALIDINTEN | ERRCONFIG_MCUVALIDINTST |
+			 ERRCONFIG_MCUBOUNDINTEN | ERRCONFIG_MCUBOUNDINTST));
+		break;
+	case SR_TYPE_V2:
+		sr_write_reg(sr, IRQSTATUS,
+			IRQSTATUS_MCUACCUMINT | IRQSTATUS_MCVALIDINT |
+			IRQSTATUS_MCBOUNDSINT | IRQSTATUS_MCUDISABLEACKINT);
+		sr_write_reg(sr, IRQENABLE_SET,
+			IRQENABLE_MCUACCUMINT | IRQENABLE_MCUVALIDINT |
+			IRQENABLE_MCUBOUNDSINT | IRQENABLE_MCUDISABLEACKINT);
+		break;
+	default:
+		dev_err(&sr->pdev->dev, "%s: Trying to Configure smartreflex module without specifying the ip\n",
+			__func__);
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+/**
+ * sr_enable() - Enables the smartreflex module.
+ * @sr:		pointer to which the SR module to be configured belongs to.
+ * @volt:	The voltage at which the Voltage domain associated with
+ *		the smartreflex module is operating at.
+ *		This is required only to program the correct Ntarget value.
+ *
+ * This API is to be called from the smartreflex class driver to
+ * enable a smartreflex module. Returns 0 on success. Returns error
+ * value if the voltage passed is wrong or if ntarget value is wrong.
+ */
+int sr_enable(struct omap_sr *sr, unsigned long volt)
+{
+	struct omap_volt_data *volt_data;
+	struct omap_sr_nvalue_table *nvalue_row;
+	int ret;
+
+	if (!sr) {
+		pr_warn("%s: NULL omap_sr from %pS\n",
+			__func__, (void *)_RET_IP_);
+		return -EINVAL;
+	}
+
+	volt_data = omap_voltage_get_voltdata(sr->voltdm, volt);
+
+	if (IS_ERR(volt_data)) {
+		dev_warn(&sr->pdev->dev, "%s: Unable to get voltage table for nominal voltage %ld\n",
+			 __func__, volt);
+		return PTR_ERR(volt_data);
+	}
+
+	nvalue_row = sr_retrieve_nvalue_row(sr, volt_data->sr_efuse_offs);
+
+	if (!nvalue_row) {
+		dev_warn(&sr->pdev->dev, "%s: failure getting SR data for this voltage %ld\n",
+			 __func__, volt);
+		return -ENODATA;
+	}
+
+	/* errminlimit is opp dependent and hence linked to voltage */
+	sr->err_minlimit = nvalue_row->errminlimit;
+
+	pm_runtime_get_sync(&sr->pdev->dev);
+
+	/* Check if SR is already enabled. If yes do nothing */
+	if (sr_read_reg(sr, SRCONFIG) & SRCONFIG_SRENABLE)
+		return 0;
+
+	/* Configure SR */
+	ret = sr_class->configure(sr);
+	if (ret)
+		return ret;
+
+	sr_write_reg(sr, NVALUERECIPROCAL, nvalue_row->nvalue);
+
+	/* SRCONFIG - enable SR */
+	sr_modify_reg(sr, SRCONFIG, SRCONFIG_SRENABLE, SRCONFIG_SRENABLE);
+	return 0;
+}
+
+/**
+ * sr_disable() - Disables the smartreflex module.
+ * @sr:		pointer to which the SR module to be configured belongs to.
+ *
+ * This API is to be called from the smartreflex class driver to
+ * disable a smartreflex module.
+ */
+void sr_disable(struct omap_sr *sr)
+{
+	if (!sr) {
+		pr_warn("%s: NULL omap_sr from %pS\n",
+			__func__, (void *)_RET_IP_);
+		return;
+	}
+
+	/* Check if SR clocks are already disabled. If yes do nothing */
+	if (pm_runtime_suspended(&sr->pdev->dev))
+		return;
+
+	/*
+	 * Disable SR if only it is indeed enabled. Else just
+	 * disable the clocks.
+	 */
+	if (sr_read_reg(sr, SRCONFIG) & SRCONFIG_SRENABLE) {
+		switch (sr->ip_type) {
+		case SR_TYPE_V1:
+			sr_v1_disable(sr);
+			break;
+		case SR_TYPE_V2:
+			sr_v2_disable(sr);
+			break;
+		default:
+			dev_err(&sr->pdev->dev, "UNKNOWN IP type %d\n",
+				sr->ip_type);
+		}
+	}
+
+	pm_runtime_put_sync_suspend(&sr->pdev->dev);
+}
+
+/**
+ * sr_register_class() - API to register a smartreflex class parameters.
+ * @class_data:	The structure containing various sr class specific data.
+ *
+ * This API is to be called by the smartreflex class driver to register itself
+ * with the smartreflex driver during init. Returns 0 on success else the
+ * error value.
+ */
+int sr_register_class(struct omap_sr_class_data *class_data)
+{
+	struct omap_sr *sr_info;
+
+	if (!class_data) {
+		pr_warn("%s:, Smartreflex class data passed is NULL\n",
+			__func__);
+		return -EINVAL;
+	}
+
+	if (sr_class) {
+		pr_warn("%s: Smartreflex class driver already registered\n",
+			__func__);
+		return -EBUSY;
+	}
+
+	sr_class = class_data;
+
+	/*
+	 * Call into late init to do initializations that require
+	 * both sr driver and sr class driver to be initiallized.
+	 */
+	list_for_each_entry(sr_info, &sr_list, node)
+		sr_late_init(sr_info);
+
+	return 0;
+}
+
+/**
+ * omap_sr_enable() -  API to enable SR clocks and to call into the
+ *			registered smartreflex class enable API.
+ * @voltdm:	VDD pointer to which the SR module to be configured belongs to.
+ *
+ * This API is to be called from the kernel in order to enable
+ * a particular smartreflex module. This API will do the initial
+ * configurations to turn on the smartreflex module and in turn call
+ * into the registered smartreflex class enable API.
+ */
+void omap_sr_enable(struct voltagedomain *voltdm)
+{
+	struct omap_sr *sr = _sr_lookup(voltdm);
+
+	if (IS_ERR(sr)) {
+		pr_warn("%s: omap_sr struct for voltdm not found\n", __func__);
+		return;
+	}
+
+	if (!sr->autocomp_active)
+		return;
+
+	if (!sr_class || !(sr_class->enable) || !(sr_class->configure)) {
+		dev_warn(&sr->pdev->dev, "%s: smartreflex class driver not registered\n",
+			 __func__);
+		return;
+	}
+
+	sr_class->enable(sr);
+}
+
+/**
+ * omap_sr_disable() - API to disable SR without resetting the voltage
+ *			processor voltage
+ * @voltdm:	VDD pointer to which the SR module to be configured belongs to.
+ *
+ * This API is to be called from the kernel in order to disable
+ * a particular smartreflex module. This API will in turn call
+ * into the registered smartreflex class disable API. This API will tell
+ * the smartreflex class disable not to reset the VP voltage after
+ * disabling smartreflex.
+ */
+void omap_sr_disable(struct voltagedomain *voltdm)
+{
+	struct omap_sr *sr = _sr_lookup(voltdm);
+
+	if (IS_ERR(sr)) {
+		pr_warn("%s: omap_sr struct for voltdm not found\n", __func__);
+		return;
+	}
+
+	if (!sr->autocomp_active)
+		return;
+
+	if (!sr_class || !(sr_class->disable)) {
+		dev_warn(&sr->pdev->dev, "%s: smartreflex class driver not registered\n",
+			 __func__);
+		return;
+	}
+
+	sr_class->disable(sr, 0);
+}
+
+/**
+ * omap_sr_disable_reset_volt() - API to disable SR and reset the
+ *				voltage processor voltage
+ * @voltdm:	VDD pointer to which the SR module to be configured belongs to.
+ *
+ * This API is to be called from the kernel in order to disable
+ * a particular smartreflex module. This API will in turn call
+ * into the registered smartreflex class disable API. This API will tell
+ * the smartreflex class disable to reset the VP voltage after
+ * disabling smartreflex.
+ */
+void omap_sr_disable_reset_volt(struct voltagedomain *voltdm)
+{
+	struct omap_sr *sr = _sr_lookup(voltdm);
+
+	if (IS_ERR(sr)) {
+		pr_warn("%s: omap_sr struct for voltdm not found\n", __func__);
+		return;
+	}
+
+	if (!sr->autocomp_active)
+		return;
+
+	if (!sr_class || !(sr_class->disable)) {
+		dev_warn(&sr->pdev->dev, "%s: smartreflex class driver not registered\n",
+			 __func__);
+		return;
+	}
+
+	sr_class->disable(sr, 1);
+}
+
+/* PM Debug FS entries to enable and disable smartreflex. */
+static int omap_sr_autocomp_show(void *data, u64 *val)
+{
+	struct omap_sr *sr_info = data;
+
+	if (!sr_info) {
+		pr_warn("%s: omap_sr struct not found\n", __func__);
+		return -EINVAL;
+	}
+
+	*val = sr_info->autocomp_active;
+
+	return 0;
+}
+
+static int omap_sr_autocomp_store(void *data, u64 val)
+{
+	struct omap_sr *sr_info = data;
+
+	if (!sr_info) {
+		pr_warn("%s: omap_sr struct not found\n", __func__);
+		return -EINVAL;
+	}
+
+	/* Sanity check */
+	if (val > 1) {
+		pr_warn("%s: Invalid argument %lld\n", __func__, val);
+		return -EINVAL;
+	}
+
+	/* control enable/disable only if there is a delta in value */
+	if (sr_info->autocomp_active != val) {
+		if (!val)
+			sr_stop_vddautocomp(sr_info);
+		else
+			sr_start_vddautocomp(sr_info);
+	}
+
+	return 0;
+}
+
+DEFINE_SIMPLE_ATTRIBUTE(pm_sr_fops, omap_sr_autocomp_show,
+			omap_sr_autocomp_store, "%llu\n");
+
+static int omap_sr_probe(struct platform_device *pdev)
+{
+	struct omap_sr *sr_info;
+	struct omap_sr_data *pdata = pdev->dev.platform_data;
+	struct resource *mem, *irq;
+	struct dentry *nvalue_dir;
+	int i, ret = 0;
+
+	sr_info = devm_kzalloc(&pdev->dev, sizeof(struct omap_sr), GFP_KERNEL);
+	if (!sr_info)
+		return -ENOMEM;
+
+	sr_info->name = devm_kzalloc(&pdev->dev,
+				     SMARTREFLEX_NAME_LEN, GFP_KERNEL);
+	if (!sr_info->name)
+		return -ENOMEM;
+
+	platform_set_drvdata(pdev, sr_info);
+
+	if (!pdata) {
+		dev_err(&pdev->dev, "%s: platform data missing\n", __func__);
+		return -EINVAL;
+	}
+
+	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	sr_info->base = devm_ioremap_resource(&pdev->dev, mem);
+	if (IS_ERR(sr_info->base)) {
+		dev_err(&pdev->dev, "%s: ioremap fail\n", __func__);
+		return PTR_ERR(sr_info->base);
+	}
+
+	irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
+
+	pm_runtime_enable(&pdev->dev);
+	pm_runtime_irq_safe(&pdev->dev);
+
+	snprintf(sr_info->name, SMARTREFLEX_NAME_LEN, "%s", pdata->name);
+
+	sr_info->pdev = pdev;
+	sr_info->srid = pdev->id;
+	sr_info->voltdm = pdata->voltdm;
+	sr_info->nvalue_table = pdata->nvalue_table;
+	sr_info->nvalue_count = pdata->nvalue_count;
+	sr_info->senn_mod = pdata->senn_mod;
+	sr_info->senp_mod = pdata->senp_mod;
+	sr_info->err_weight = pdata->err_weight;
+	sr_info->err_maxlimit = pdata->err_maxlimit;
+	sr_info->accum_data = pdata->accum_data;
+	sr_info->senn_avgweight = pdata->senn_avgweight;
+	sr_info->senp_avgweight = pdata->senp_avgweight;
+	sr_info->autocomp_active = false;
+	sr_info->ip_type = pdata->ip_type;
+
+	if (irq)
+		sr_info->irq = irq->start;
+
+	sr_set_clk_length(sr_info);
+
+	list_add(&sr_info->node, &sr_list);
+
+	ret = pm_runtime_get_sync(&pdev->dev);
+	if (ret < 0) {
+		pm_runtime_put_noidle(&pdev->dev);
+		goto err_list_del;
+	}
+
+	/*
+	 * Call into late init to do initializations that require
+	 * both sr driver and sr class driver to be initiallized.
+	 */
+	if (sr_class) {
+		ret = sr_late_init(sr_info);
+		if (ret) {
+			pr_warn("%s: Error in SR late init\n", __func__);
+			goto err_list_del;
+		}
+	}
+
+	dev_info(&pdev->dev, "%s: SmartReflex driver initialized\n", __func__);
+	if (!sr_dbg_dir)
+		sr_dbg_dir = debugfs_create_dir("smartreflex", NULL);
+
+	sr_info->dbg_dir = debugfs_create_dir(sr_info->name, sr_dbg_dir);
+
+	debugfs_create_file("autocomp", S_IRUGO | S_IWUSR, sr_info->dbg_dir,
+			    sr_info, &pm_sr_fops);
+	debugfs_create_x32("errweight", S_IRUGO, sr_info->dbg_dir,
+			   &sr_info->err_weight);
+	debugfs_create_x32("errmaxlimit", S_IRUGO, sr_info->dbg_dir,
+			   &sr_info->err_maxlimit);
+
+	nvalue_dir = debugfs_create_dir("nvalue", sr_info->dbg_dir);
+
+	if (sr_info->nvalue_count == 0 || !sr_info->nvalue_table) {
+		dev_warn(&pdev->dev, "%s: %s: No Voltage table for the corresponding vdd. Cannot create debugfs entries for n-values\n",
+			 __func__, sr_info->name);
+
+		ret = -ENODATA;
+		goto err_debugfs;
+	}
+
+	for (i = 0; i < sr_info->nvalue_count; i++) {
+		char name[NVALUE_NAME_LEN + 1];
+
+		snprintf(name, sizeof(name), "volt_%lu",
+				sr_info->nvalue_table[i].volt_nominal);
+		debugfs_create_x32(name, S_IRUGO | S_IWUSR, nvalue_dir,
+				   &(sr_info->nvalue_table[i].nvalue));
+		snprintf(name, sizeof(name), "errminlimit_%lu",
+			 sr_info->nvalue_table[i].volt_nominal);
+		debugfs_create_x32(name, S_IRUGO | S_IWUSR, nvalue_dir,
+				   &(sr_info->nvalue_table[i].errminlimit));
+
+	}
+
+	pm_runtime_put_sync(&pdev->dev);
+
+	return ret;
+
+err_debugfs:
+	debugfs_remove_recursive(sr_info->dbg_dir);
+err_list_del:
+	list_del(&sr_info->node);
+
+	pm_runtime_put_sync(&pdev->dev);
+
+	return ret;
+}
+
+static int omap_sr_remove(struct platform_device *pdev)
+{
+	struct omap_sr_data *pdata = pdev->dev.platform_data;
+	struct omap_sr *sr_info;
+
+	if (!pdata) {
+		dev_err(&pdev->dev, "%s: platform data missing\n", __func__);
+		return -EINVAL;
+	}
+
+	sr_info = _sr_lookup(pdata->voltdm);
+	if (IS_ERR(sr_info)) {
+		dev_warn(&pdev->dev, "%s: omap_sr struct not found\n",
+			__func__);
+		return PTR_ERR(sr_info);
+	}
+
+	if (sr_info->autocomp_active)
+		sr_stop_vddautocomp(sr_info);
+	debugfs_remove_recursive(sr_info->dbg_dir);
+
+	pm_runtime_disable(&pdev->dev);
+	list_del(&sr_info->node);
+	return 0;
+}
+
+static void omap_sr_shutdown(struct platform_device *pdev)
+{
+	struct omap_sr_data *pdata = pdev->dev.platform_data;
+	struct omap_sr *sr_info;
+
+	if (!pdata) {
+		dev_err(&pdev->dev, "%s: platform data missing\n", __func__);
+		return;
+	}
+
+	sr_info = _sr_lookup(pdata->voltdm);
+	if (IS_ERR(sr_info)) {
+		dev_warn(&pdev->dev, "%s: omap_sr struct not found\n",
+			__func__);
+		return;
+	}
+
+	if (sr_info->autocomp_active)
+		sr_stop_vddautocomp(sr_info);
+
+	return;
+}
+
+static const struct of_device_id omap_sr_match[] = {
+	{ .compatible = "ti,omap3-smartreflex-core", },
+	{ .compatible = "ti,omap3-smartreflex-mpu-iva", },
+	{ .compatible = "ti,omap4-smartreflex-core", },
+	{ .compatible = "ti,omap4-smartreflex-mpu", },
+	{ .compatible = "ti,omap4-smartreflex-iva", },
+	{  },
+};
+MODULE_DEVICE_TABLE(of, omap_sr_match);
+
+static struct platform_driver smartreflex_driver = {
+	.probe		= omap_sr_probe,
+	.remove         = omap_sr_remove,
+	.shutdown	= omap_sr_shutdown,
+	.driver		= {
+		.name	= DRIVER_NAME,
+		.of_match_table	= omap_sr_match,
+	},
+};
+
+static int __init sr_init(void)
+{
+	int ret = 0;
+
+	ret = platform_driver_register(&smartreflex_driver);
+	if (ret) {
+		pr_err("%s: platform driver register failed for SR\n",
+		       __func__);
+		return ret;
+	}
+
+	return 0;
+}
+late_initcall(sr_init);
+
+static void __exit sr_exit(void)
+{
+	platform_driver_unregister(&smartreflex_driver);
+}
+module_exit(sr_exit);
+
+MODULE_DESCRIPTION("OMAP Smartreflex Driver");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:" DRIVER_NAME);
+MODULE_AUTHOR("Texas Instruments Inc");