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-rw-r--r--drivers/clk/ti/clkctrl.c750
1 files changed, 750 insertions, 0 deletions
diff --git a/drivers/clk/ti/clkctrl.c b/drivers/clk/ti/clkctrl.c
new file mode 100644
index 0000000000..607e34d8e2
--- /dev/null
+++ b/drivers/clk/ti/clkctrl.c
@@ -0,0 +1,750 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * OMAP clkctrl clock support
+ *
+ * Copyright (C) 2017 Texas Instruments, Inc.
+ *
+ * Tero Kristo <t-kristo@ti.com>
+ */
+
+#include <linux/clk-provider.h>
+#include <linux/slab.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/clk/ti.h>
+#include <linux/delay.h>
+#include <linux/string_helpers.h>
+#include <linux/timekeeping.h>
+#include "clock.h"
+
+#define NO_IDLEST 0
+
+#define OMAP4_MODULEMODE_MASK 0x3
+
+#define MODULEMODE_HWCTRL 0x1
+#define MODULEMODE_SWCTRL 0x2
+
+#define OMAP4_IDLEST_MASK (0x3 << 16)
+#define OMAP4_IDLEST_SHIFT 16
+
+#define OMAP4_STBYST_MASK BIT(18)
+#define OMAP4_STBYST_SHIFT 18
+
+#define CLKCTRL_IDLEST_FUNCTIONAL 0x0
+#define CLKCTRL_IDLEST_INTERFACE_IDLE 0x2
+#define CLKCTRL_IDLEST_DISABLED 0x3
+
+/* These timeouts are in us */
+#define OMAP4_MAX_MODULE_READY_TIME 2000
+#define OMAP4_MAX_MODULE_DISABLE_TIME 5000
+
+static bool _early_timeout = true;
+
+struct omap_clkctrl_provider {
+ void __iomem *base;
+ struct list_head clocks;
+ char *clkdm_name;
+};
+
+struct omap_clkctrl_clk {
+ struct clk_hw *clk;
+ u16 reg_offset;
+ int bit_offset;
+ struct list_head node;
+};
+
+union omap4_timeout {
+ u32 cycles;
+ ktime_t start;
+};
+
+static const struct omap_clkctrl_data default_clkctrl_data[] __initconst = {
+ { 0 },
+};
+
+static u32 _omap4_idlest(u32 val)
+{
+ val &= OMAP4_IDLEST_MASK;
+ val >>= OMAP4_IDLEST_SHIFT;
+
+ return val;
+}
+
+static bool _omap4_is_idle(u32 val)
+{
+ val = _omap4_idlest(val);
+
+ return val == CLKCTRL_IDLEST_DISABLED;
+}
+
+static bool _omap4_is_ready(u32 val)
+{
+ val = _omap4_idlest(val);
+
+ return val == CLKCTRL_IDLEST_FUNCTIONAL ||
+ val == CLKCTRL_IDLEST_INTERFACE_IDLE;
+}
+
+static bool _omap4_is_timeout(union omap4_timeout *time, u32 timeout)
+{
+ /*
+ * There are two special cases where ktime_to_ns() can't be
+ * used to track the timeouts. First one is during early boot
+ * when the timers haven't been initialized yet. The second
+ * one is during suspend-resume cycle while timekeeping is
+ * being suspended / resumed. Clocksource for the system
+ * can be from a timer that requires pm_runtime access, which
+ * will eventually bring us here with timekeeping_suspended,
+ * during both suspend entry and resume paths. This happens
+ * at least on am43xx platform. Account for flakeyness
+ * with udelay() by multiplying the timeout value by 2.
+ */
+ if (unlikely(_early_timeout || timekeeping_suspended)) {
+ if (time->cycles++ < timeout) {
+ udelay(1 * 2);
+ return false;
+ }
+ } else {
+ if (!ktime_to_ns(time->start)) {
+ time->start = ktime_get();
+ return false;
+ }
+
+ if (ktime_us_delta(ktime_get(), time->start) < timeout) {
+ cpu_relax();
+ return false;
+ }
+ }
+
+ return true;
+}
+
+static int __init _omap4_disable_early_timeout(void)
+{
+ _early_timeout = false;
+
+ return 0;
+}
+arch_initcall(_omap4_disable_early_timeout);
+
+static int _omap4_clkctrl_clk_enable(struct clk_hw *hw)
+{
+ struct clk_hw_omap *clk = to_clk_hw_omap(hw);
+ u32 val;
+ int ret;
+ union omap4_timeout timeout = { 0 };
+
+ if (clk->clkdm) {
+ ret = ti_clk_ll_ops->clkdm_clk_enable(clk->clkdm, hw->clk);
+ if (ret) {
+ WARN(1,
+ "%s: could not enable %s's clockdomain %s: %d\n",
+ __func__, clk_hw_get_name(hw),
+ clk->clkdm_name, ret);
+ return ret;
+ }
+ }
+
+ if (!clk->enable_bit)
+ return 0;
+
+ val = ti_clk_ll_ops->clk_readl(&clk->enable_reg);
+
+ val &= ~OMAP4_MODULEMODE_MASK;
+ val |= clk->enable_bit;
+
+ ti_clk_ll_ops->clk_writel(val, &clk->enable_reg);
+
+ if (test_bit(NO_IDLEST, &clk->flags))
+ return 0;
+
+ /* Wait until module is enabled */
+ while (!_omap4_is_ready(ti_clk_ll_ops->clk_readl(&clk->enable_reg))) {
+ if (_omap4_is_timeout(&timeout, OMAP4_MAX_MODULE_READY_TIME)) {
+ pr_err("%s: failed to enable\n", clk_hw_get_name(hw));
+ return -EBUSY;
+ }
+ }
+
+ return 0;
+}
+
+static void _omap4_clkctrl_clk_disable(struct clk_hw *hw)
+{
+ struct clk_hw_omap *clk = to_clk_hw_omap(hw);
+ u32 val;
+ union omap4_timeout timeout = { 0 };
+
+ if (!clk->enable_bit)
+ goto exit;
+
+ val = ti_clk_ll_ops->clk_readl(&clk->enable_reg);
+
+ val &= ~OMAP4_MODULEMODE_MASK;
+
+ ti_clk_ll_ops->clk_writel(val, &clk->enable_reg);
+
+ if (test_bit(NO_IDLEST, &clk->flags))
+ goto exit;
+
+ /* Wait until module is disabled */
+ while (!_omap4_is_idle(ti_clk_ll_ops->clk_readl(&clk->enable_reg))) {
+ if (_omap4_is_timeout(&timeout,
+ OMAP4_MAX_MODULE_DISABLE_TIME)) {
+ pr_err("%s: failed to disable\n", clk_hw_get_name(hw));
+ break;
+ }
+ }
+
+exit:
+ if (clk->clkdm)
+ ti_clk_ll_ops->clkdm_clk_disable(clk->clkdm, hw->clk);
+}
+
+static int _omap4_clkctrl_clk_is_enabled(struct clk_hw *hw)
+{
+ struct clk_hw_omap *clk = to_clk_hw_omap(hw);
+ u32 val;
+
+ val = ti_clk_ll_ops->clk_readl(&clk->enable_reg);
+
+ if (val & clk->enable_bit)
+ return 1;
+
+ return 0;
+}
+
+static const struct clk_ops omap4_clkctrl_clk_ops = {
+ .enable = _omap4_clkctrl_clk_enable,
+ .disable = _omap4_clkctrl_clk_disable,
+ .is_enabled = _omap4_clkctrl_clk_is_enabled,
+ .init = omap2_init_clk_clkdm,
+};
+
+static struct clk_hw *_ti_omap4_clkctrl_xlate(struct of_phandle_args *clkspec,
+ void *data)
+{
+ struct omap_clkctrl_provider *provider = data;
+ struct omap_clkctrl_clk *entry = NULL, *iter;
+
+ if (clkspec->args_count != 2)
+ return ERR_PTR(-EINVAL);
+
+ pr_debug("%s: looking for %x:%x\n", __func__,
+ clkspec->args[0], clkspec->args[1]);
+
+ list_for_each_entry(iter, &provider->clocks, node) {
+ if (iter->reg_offset == clkspec->args[0] &&
+ iter->bit_offset == clkspec->args[1]) {
+ entry = iter;
+ break;
+ }
+ }
+
+ if (!entry)
+ return ERR_PTR(-EINVAL);
+
+ return entry->clk;
+}
+
+/* Get clkctrl clock base name based on clkctrl_name or dts node */
+static const char * __init clkctrl_get_clock_name(struct device_node *np,
+ const char *clkctrl_name,
+ int offset, int index,
+ bool legacy_naming)
+{
+ char *clock_name;
+
+ /* l4per-clkctrl:1234:0 style naming based on clkctrl_name */
+ if (clkctrl_name && !legacy_naming) {
+ clock_name = kasprintf(GFP_KERNEL, "%s-clkctrl:%04x:%d",
+ clkctrl_name, offset, index);
+ if (!clock_name)
+ return NULL;
+
+ strreplace(clock_name, '_', '-');
+
+ return clock_name;
+ }
+
+ /* l4per:1234:0 old style naming based on clkctrl_name */
+ if (clkctrl_name)
+ return kasprintf(GFP_KERNEL, "%s_cm:clk:%04x:%d",
+ clkctrl_name, offset, index);
+
+ /* l4per_cm:1234:0 old style naming based on parent node name */
+ if (legacy_naming)
+ return kasprintf(GFP_KERNEL, "%pOFn:clk:%04x:%d",
+ np->parent, offset, index);
+
+ /* l4per-clkctrl:1234:0 style naming based on node name */
+ return kasprintf(GFP_KERNEL, "%pOFn:%04x:%d", np, offset, index);
+}
+
+static int __init
+_ti_clkctrl_clk_register(struct omap_clkctrl_provider *provider,
+ struct device_node *node, struct clk_hw *clk_hw,
+ u16 offset, u8 bit, const char * const *parents,
+ int num_parents, const struct clk_ops *ops,
+ const char *clkctrl_name)
+{
+ struct clk_init_data init = { NULL };
+ struct clk *clk;
+ struct omap_clkctrl_clk *clkctrl_clk;
+ int ret = 0;
+
+ init.name = clkctrl_get_clock_name(node, clkctrl_name, offset, bit,
+ ti_clk_get_features()->flags &
+ TI_CLK_CLKCTRL_COMPAT);
+
+ clkctrl_clk = kzalloc(sizeof(*clkctrl_clk), GFP_KERNEL);
+ if (!init.name || !clkctrl_clk) {
+ ret = -ENOMEM;
+ goto cleanup;
+ }
+
+ clk_hw->init = &init;
+ init.parent_names = parents;
+ init.num_parents = num_parents;
+ init.ops = ops;
+ init.flags = 0;
+
+ clk = of_ti_clk_register(node, clk_hw, init.name);
+ if (IS_ERR_OR_NULL(clk)) {
+ ret = -EINVAL;
+ goto cleanup;
+ }
+
+ clkctrl_clk->reg_offset = offset;
+ clkctrl_clk->bit_offset = bit;
+ clkctrl_clk->clk = clk_hw;
+
+ list_add(&clkctrl_clk->node, &provider->clocks);
+
+ return 0;
+
+cleanup:
+ kfree(init.name);
+ kfree(clkctrl_clk);
+ return ret;
+}
+
+static void __init
+_ti_clkctrl_setup_gate(struct omap_clkctrl_provider *provider,
+ struct device_node *node, u16 offset,
+ const struct omap_clkctrl_bit_data *data,
+ void __iomem *reg, const char *clkctrl_name)
+{
+ struct clk_hw_omap *clk_hw;
+
+ clk_hw = kzalloc(sizeof(*clk_hw), GFP_KERNEL);
+ if (!clk_hw)
+ return;
+
+ clk_hw->enable_bit = data->bit;
+ clk_hw->enable_reg.ptr = reg;
+
+ if (_ti_clkctrl_clk_register(provider, node, &clk_hw->hw, offset,
+ data->bit, data->parents, 1,
+ &omap_gate_clk_ops, clkctrl_name))
+ kfree(clk_hw);
+}
+
+static void __init
+_ti_clkctrl_setup_mux(struct omap_clkctrl_provider *provider,
+ struct device_node *node, u16 offset,
+ const struct omap_clkctrl_bit_data *data,
+ void __iomem *reg, const char *clkctrl_name)
+{
+ struct clk_omap_mux *mux;
+ int num_parents = 0;
+ const char * const *pname;
+
+ mux = kzalloc(sizeof(*mux), GFP_KERNEL);
+ if (!mux)
+ return;
+
+ pname = data->parents;
+ while (*pname) {
+ num_parents++;
+ pname++;
+ }
+
+ mux->mask = num_parents;
+ if (!(mux->flags & CLK_MUX_INDEX_ONE))
+ mux->mask--;
+
+ mux->mask = (1 << fls(mux->mask)) - 1;
+
+ mux->shift = data->bit;
+ mux->reg.ptr = reg;
+
+ if (_ti_clkctrl_clk_register(provider, node, &mux->hw, offset,
+ data->bit, data->parents, num_parents,
+ &ti_clk_mux_ops, clkctrl_name))
+ kfree(mux);
+}
+
+static void __init
+_ti_clkctrl_setup_div(struct omap_clkctrl_provider *provider,
+ struct device_node *node, u16 offset,
+ const struct omap_clkctrl_bit_data *data,
+ void __iomem *reg, const char *clkctrl_name)
+{
+ struct clk_omap_divider *div;
+ const struct omap_clkctrl_div_data *div_data = data->data;
+ u8 div_flags = 0;
+
+ div = kzalloc(sizeof(*div), GFP_KERNEL);
+ if (!div)
+ return;
+
+ div->reg.ptr = reg;
+ div->shift = data->bit;
+ div->flags = div_data->flags;
+
+ if (div->flags & CLK_DIVIDER_POWER_OF_TWO)
+ div_flags |= CLKF_INDEX_POWER_OF_TWO;
+
+ if (ti_clk_parse_divider_data((int *)div_data->dividers, 0,
+ div_data->max_div, div_flags,
+ div)) {
+ pr_err("%s: Data parsing for %pOF:%04x:%d failed\n", __func__,
+ node, offset, data->bit);
+ kfree(div);
+ return;
+ }
+
+ if (_ti_clkctrl_clk_register(provider, node, &div->hw, offset,
+ data->bit, data->parents, 1,
+ &ti_clk_divider_ops, clkctrl_name))
+ kfree(div);
+}
+
+static void __init
+_ti_clkctrl_setup_subclks(struct omap_clkctrl_provider *provider,
+ struct device_node *node,
+ const struct omap_clkctrl_reg_data *data,
+ void __iomem *reg, const char *clkctrl_name)
+{
+ const struct omap_clkctrl_bit_data *bits = data->bit_data;
+
+ if (!bits)
+ return;
+
+ while (bits->bit) {
+ switch (bits->type) {
+ case TI_CLK_GATE:
+ _ti_clkctrl_setup_gate(provider, node, data->offset,
+ bits, reg, clkctrl_name);
+ break;
+
+ case TI_CLK_DIVIDER:
+ _ti_clkctrl_setup_div(provider, node, data->offset,
+ bits, reg, clkctrl_name);
+ break;
+
+ case TI_CLK_MUX:
+ _ti_clkctrl_setup_mux(provider, node, data->offset,
+ bits, reg, clkctrl_name);
+ break;
+
+ default:
+ pr_err("%s: bad subclk type: %d\n", __func__,
+ bits->type);
+ return;
+ }
+ bits++;
+ }
+}
+
+static void __init _clkctrl_add_provider(void *data,
+ struct device_node *np)
+{
+ of_clk_add_hw_provider(np, _ti_omap4_clkctrl_xlate, data);
+}
+
+/*
+ * Get clock name based on "clock-output-names" property or the
+ * compatible property for clkctrl.
+ */
+static const char * __init clkctrl_get_name(struct device_node *np)
+{
+ struct property *prop;
+ const int prefix_len = 11;
+ const char *compat;
+ const char *output;
+ const char *end;
+ char *name;
+
+ if (!of_property_read_string_index(np, "clock-output-names", 0,
+ &output)) {
+ int len;
+
+ len = strlen(output);
+ end = strstr(output, "_clkctrl");
+ if (end)
+ len -= strlen(end);
+ name = kstrndup(output, len, GFP_KERNEL);
+
+ return name;
+ }
+
+ of_property_for_each_string(np, "compatible", prop, compat) {
+ if (!strncmp("ti,clkctrl-", compat, prefix_len)) {
+ end = compat + prefix_len;
+ /* Two letter minimum name length for l3, l4 etc */
+ if (strnlen(end, 16) < 2)
+ continue;
+ name = kstrdup_and_replace(end, '-', '_', GFP_KERNEL);
+ if (!name)
+ continue;
+
+ return name;
+ }
+ }
+
+ return NULL;
+}
+
+static void __init _ti_omap4_clkctrl_setup(struct device_node *node)
+{
+ struct omap_clkctrl_provider *provider;
+ const struct omap_clkctrl_data *data = default_clkctrl_data;
+ const struct omap_clkctrl_reg_data *reg_data;
+ struct clk_init_data init = { NULL };
+ struct clk_hw_omap *hw;
+ struct clk *clk;
+ struct omap_clkctrl_clk *clkctrl_clk = NULL;
+ bool legacy_naming;
+ const char *clkctrl_name;
+ u32 addr;
+ int ret;
+ char *c;
+ u16 soc_mask = 0;
+ struct resource res;
+
+ of_address_to_resource(node, 0, &res);
+ addr = (u32)res.start;
+
+#ifdef CONFIG_ARCH_OMAP4
+ if (of_machine_is_compatible("ti,omap4"))
+ data = omap4_clkctrl_data;
+#endif
+#ifdef CONFIG_SOC_OMAP5
+ if (of_machine_is_compatible("ti,omap5"))
+ data = omap5_clkctrl_data;
+#endif
+#ifdef CONFIG_SOC_DRA7XX
+ if (of_machine_is_compatible("ti,dra7"))
+ data = dra7_clkctrl_data;
+ if (of_machine_is_compatible("ti,dra72"))
+ soc_mask = CLKF_SOC_DRA72;
+ if (of_machine_is_compatible("ti,dra74"))
+ soc_mask = CLKF_SOC_DRA74;
+ if (of_machine_is_compatible("ti,dra76"))
+ soc_mask = CLKF_SOC_DRA76;
+#endif
+#ifdef CONFIG_SOC_AM33XX
+ if (of_machine_is_compatible("ti,am33xx"))
+ data = am3_clkctrl_data;
+#endif
+#ifdef CONFIG_SOC_AM43XX
+ if (of_machine_is_compatible("ti,am4372"))
+ data = am4_clkctrl_data;
+
+ if (of_machine_is_compatible("ti,am438x"))
+ data = am438x_clkctrl_data;
+#endif
+#ifdef CONFIG_SOC_TI81XX
+ if (of_machine_is_compatible("ti,dm814"))
+ data = dm814_clkctrl_data;
+
+ if (of_machine_is_compatible("ti,dm816"))
+ data = dm816_clkctrl_data;
+#endif
+
+ if (ti_clk_get_features()->flags & TI_CLK_DEVICE_TYPE_GP)
+ soc_mask |= CLKF_SOC_NONSEC;
+
+ while (data->addr) {
+ if (addr == data->addr)
+ break;
+
+ data++;
+ }
+
+ if (!data->addr) {
+ pr_err("%pOF not found from clkctrl data.\n", node);
+ return;
+ }
+
+ provider = kzalloc(sizeof(*provider), GFP_KERNEL);
+ if (!provider)
+ return;
+
+ provider->base = of_iomap(node, 0);
+
+ legacy_naming = ti_clk_get_features()->flags & TI_CLK_CLKCTRL_COMPAT;
+ clkctrl_name = clkctrl_get_name(node);
+ if (clkctrl_name) {
+ provider->clkdm_name = kasprintf(GFP_KERNEL,
+ "%s_clkdm", clkctrl_name);
+ if (!provider->clkdm_name) {
+ kfree(provider);
+ return;
+ }
+ goto clkdm_found;
+ }
+
+ /*
+ * The code below can be removed when all clkctrl nodes use domain
+ * specific compatible property and standard clock node naming
+ */
+ if (legacy_naming) {
+ provider->clkdm_name = kasprintf(GFP_KERNEL, "%pOFnxxx", node->parent);
+ if (!provider->clkdm_name) {
+ kfree(provider);
+ return;
+ }
+
+ /*
+ * Create default clkdm name, replace _cm from end of parent
+ * node name with _clkdm
+ */
+ provider->clkdm_name[strlen(provider->clkdm_name) - 2] = 0;
+ } else {
+ provider->clkdm_name = kasprintf(GFP_KERNEL, "%pOFn", node);
+ if (!provider->clkdm_name) {
+ kfree(provider);
+ return;
+ }
+
+ /*
+ * Create default clkdm name, replace _clkctrl from end of
+ * node name with _clkdm
+ */
+ provider->clkdm_name[strlen(provider->clkdm_name) - 7] = 0;
+ }
+
+ strcat(provider->clkdm_name, "clkdm");
+
+ /* Replace any dash from the clkdm name with underscore */
+ c = provider->clkdm_name;
+
+ while (*c) {
+ if (*c == '-')
+ *c = '_';
+ c++;
+ }
+clkdm_found:
+ INIT_LIST_HEAD(&provider->clocks);
+
+ /* Generate clocks */
+ reg_data = data->regs;
+
+ while (reg_data->parent) {
+ if ((reg_data->flags & CLKF_SOC_MASK) &&
+ (reg_data->flags & soc_mask) == 0) {
+ reg_data++;
+ continue;
+ }
+
+ hw = kzalloc(sizeof(*hw), GFP_KERNEL);
+ if (!hw)
+ return;
+
+ hw->enable_reg.ptr = provider->base + reg_data->offset;
+
+ _ti_clkctrl_setup_subclks(provider, node, reg_data,
+ hw->enable_reg.ptr, clkctrl_name);
+
+ if (reg_data->flags & CLKF_SW_SUP)
+ hw->enable_bit = MODULEMODE_SWCTRL;
+ if (reg_data->flags & CLKF_HW_SUP)
+ hw->enable_bit = MODULEMODE_HWCTRL;
+ if (reg_data->flags & CLKF_NO_IDLEST)
+ set_bit(NO_IDLEST, &hw->flags);
+
+ if (reg_data->clkdm_name)
+ hw->clkdm_name = reg_data->clkdm_name;
+ else
+ hw->clkdm_name = provider->clkdm_name;
+
+ init.parent_names = &reg_data->parent;
+ init.num_parents = 1;
+ init.flags = 0;
+ if (reg_data->flags & CLKF_SET_RATE_PARENT)
+ init.flags |= CLK_SET_RATE_PARENT;
+
+ init.name = clkctrl_get_clock_name(node, clkctrl_name,
+ reg_data->offset, 0,
+ legacy_naming);
+ if (!init.name)
+ goto cleanup;
+
+ clkctrl_clk = kzalloc(sizeof(*clkctrl_clk), GFP_KERNEL);
+ if (!clkctrl_clk)
+ goto cleanup;
+
+ init.ops = &omap4_clkctrl_clk_ops;
+ hw->hw.init = &init;
+
+ clk = of_ti_clk_register_omap_hw(node, &hw->hw, init.name);
+ if (IS_ERR_OR_NULL(clk))
+ goto cleanup;
+
+ clkctrl_clk->reg_offset = reg_data->offset;
+ clkctrl_clk->clk = &hw->hw;
+
+ list_add(&clkctrl_clk->node, &provider->clocks);
+
+ reg_data++;
+ }
+
+ ret = of_clk_add_hw_provider(node, _ti_omap4_clkctrl_xlate, provider);
+ if (ret == -EPROBE_DEFER)
+ ti_clk_retry_init(node, provider, _clkctrl_add_provider);
+
+ kfree(clkctrl_name);
+
+ return;
+
+cleanup:
+ kfree(hw);
+ kfree(init.name);
+ kfree(clkctrl_name);
+ kfree(clkctrl_clk);
+}
+CLK_OF_DECLARE(ti_omap4_clkctrl_clock, "ti,clkctrl",
+ _ti_omap4_clkctrl_setup);
+
+/**
+ * ti_clk_is_in_standby - Check if clkctrl clock is in standby or not
+ * @clk: clock to check standby status for
+ *
+ * Finds whether the provided clock is in standby mode or not. Returns
+ * true if the provided clock is a clkctrl type clock and it is in standby,
+ * false otherwise.
+ */
+bool ti_clk_is_in_standby(struct clk *clk)
+{
+ struct clk_hw *hw;
+ struct clk_hw_omap *hwclk;
+ u32 val;
+
+ hw = __clk_get_hw(clk);
+
+ if (!omap2_clk_is_hw_omap(hw))
+ return false;
+
+ hwclk = to_clk_hw_omap(hw);
+
+ val = ti_clk_ll_ops->clk_readl(&hwclk->enable_reg);
+
+ if (val & OMAP4_STBYST_MASK)
+ return true;
+
+ return false;
+}
+EXPORT_SYMBOL_GPL(ti_clk_is_in_standby);