[PATCH V2 1/3] clk: ux500: Add support for sysctrl clocks
Ulf Hansson
ulf.hansson at stericsson.com
Wed Apr 3 05:46:52 EDT 2013
From: Ulf Hansson <ulf.hansson at linaro.org>
The abx500 sysctrl clocks are using the ab8500 sysctrl driver to
modify the clock hardware. Sysctrl clocks are represented by a
ab8500 sysctrl register and with a corresponding bitmask.
The sysctrl clocks are slow path clocks, which means clk_prepare
and clk_unprepare will be used to gate|ungate these clocks.
Signed-off-by: Ulf Hansson <ulf.hansson at linaro.org>
---
Changes in v2:
- Removed wrong header file.
---
drivers/clk/ux500/Makefile | 1 +
drivers/clk/ux500/clk-sysctrl.c | 223 +++++++++++++++++++++++++++++++++++++++
drivers/clk/ux500/clk.h | 29 +++++
3 files changed, 253 insertions(+)
create mode 100644 drivers/clk/ux500/clk-sysctrl.c
diff --git a/drivers/clk/ux500/Makefile b/drivers/clk/ux500/Makefile
index bcc0c11..c6a806e 100644
--- a/drivers/clk/ux500/Makefile
+++ b/drivers/clk/ux500/Makefile
@@ -5,6 +5,7 @@
# Clock types
obj-y += clk-prcc.o
obj-y += clk-prcmu.o
+obj-y += clk-sysctrl.o
# Clock definitions
obj-y += u8500_clk.o
diff --git a/drivers/clk/ux500/clk-sysctrl.c b/drivers/clk/ux500/clk-sysctrl.c
new file mode 100644
index 0000000..162a02b
--- /dev/null
+++ b/drivers/clk/ux500/clk-sysctrl.c
@@ -0,0 +1,223 @@
+/*
+ * Sysctrl clock implementation for ux500 platform.
+ *
+ * Copyright (C) 2013 ST-Ericsson SA
+ * Author: Ulf Hansson <ulf.hansson at linaro.org>
+ *
+ * License terms: GNU General Public License (GPL) version 2
+ */
+
+#include <linux/clk-provider.h>
+#include <linux/mfd/abx500/ab8500-sysctrl.h>
+#include <linux/device.h>
+#include <linux/slab.h>
+#include <linux/delay.h>
+#include <linux/io.h>
+#include <linux/err.h>
+#include "clk.h"
+
+#define SYSCTRL_MAX_NUM_PARENTS 4
+
+#define to_clk_sysctrl(_hw) container_of(_hw, struct clk_sysctrl, hw)
+
+struct clk_sysctrl {
+ struct clk_hw hw;
+ struct device *dev;
+ u8 parent_index;
+ u16 reg_sel[SYSCTRL_MAX_NUM_PARENTS];
+ u8 reg_mask[SYSCTRL_MAX_NUM_PARENTS];
+ u8 reg_bits[SYSCTRL_MAX_NUM_PARENTS];
+ unsigned long rate;
+ unsigned long enable_delay_us;
+};
+
+/* Sysctrl clock operations. */
+
+static int clk_sysctrl_prepare(struct clk_hw *hw)
+{
+ int ret;
+ struct clk_sysctrl *clk = to_clk_sysctrl(hw);
+
+ ret = ab8500_sysctrl_write(clk->reg_sel[0], clk->reg_mask[0],
+ clk->reg_bits[0]);
+
+ if (!ret && clk->enable_delay_us)
+ usleep_range(clk->enable_delay_us, clk->enable_delay_us);
+
+ return ret;
+}
+
+static void clk_sysctrl_unprepare(struct clk_hw *hw)
+{
+ struct clk_sysctrl *clk = to_clk_sysctrl(hw);
+ if (ab8500_sysctrl_clear(clk->reg_sel[0], clk->reg_mask[0]))
+ dev_err(clk->dev, "clk_sysctrl: %s fail to clear %s.\n",
+ __func__, __clk_get_name(hw->clk));
+}
+
+static unsigned long clk_sysctrl_recalc_rate(struct clk_hw *hw,
+ unsigned long parent_rate)
+{
+ struct clk_sysctrl *clk = to_clk_sysctrl(hw);
+ return clk->rate;
+}
+
+static int clk_sysctrl_set_parent(struct clk_hw *hw, u8 index)
+{
+ struct clk_sysctrl *clk = to_clk_sysctrl(hw);
+ u8 old_index = clk->parent_index;
+ int ret = 0;
+
+ if (clk->reg_sel[old_index]) {
+ ret = ab8500_sysctrl_clear(clk->reg_sel[old_index],
+ clk->reg_mask[old_index]);
+ if (ret)
+ return ret;
+ }
+
+ if (clk->reg_sel[index]) {
+ ret = ab8500_sysctrl_write(clk->reg_sel[index],
+ clk->reg_mask[index],
+ clk->reg_bits[index]);
+ if (ret) {
+ if (clk->reg_sel[old_index])
+ ab8500_sysctrl_write(clk->reg_sel[old_index],
+ clk->reg_mask[old_index],
+ clk->reg_bits[old_index]);
+ return ret;
+ }
+ }
+ clk->parent_index = index;
+
+ return ret;
+}
+
+static u8 clk_sysctrl_get_parent(struct clk_hw *hw)
+{
+ struct clk_sysctrl *clk = to_clk_sysctrl(hw);
+ return clk->parent_index;
+}
+
+static struct clk_ops clk_sysctrl_gate_ops = {
+ .prepare = clk_sysctrl_prepare,
+ .unprepare = clk_sysctrl_unprepare,
+};
+
+static struct clk_ops clk_sysctrl_gate_fixed_rate_ops = {
+ .prepare = clk_sysctrl_prepare,
+ .unprepare = clk_sysctrl_unprepare,
+ .recalc_rate = clk_sysctrl_recalc_rate,
+};
+
+static struct clk_ops clk_sysctrl_set_parent_ops = {
+ .set_parent = clk_sysctrl_set_parent,
+ .get_parent = clk_sysctrl_get_parent,
+};
+
+static struct clk *clk_reg_sysctrl(struct device *dev,
+ const char *name,
+ const char **parent_names,
+ u8 num_parents,
+ u16 *reg_sel,
+ u8 *reg_mask,
+ u8 *reg_bits,
+ unsigned long rate,
+ unsigned long enable_delay_us,
+ unsigned long flags,
+ struct clk_ops *clk_sysctrl_ops)
+{
+ struct clk_sysctrl *clk;
+ struct clk_init_data clk_sysctrl_init;
+ struct clk *clk_reg;
+ int i;
+
+ if (!dev)
+ return ERR_PTR(-EINVAL);
+
+ if (!name || (num_parents > SYSCTRL_MAX_NUM_PARENTS)) {
+ dev_err(dev, "clk_sysctrl: invalid arguments passed\n");
+ return ERR_PTR(-EINVAL);
+ }
+
+ clk = devm_kzalloc(dev, sizeof(struct clk_sysctrl), GFP_KERNEL);
+ if (!clk) {
+ dev_err(dev, "clk_sysctrl: could not allocate clk\n");
+ return ERR_PTR(-ENOMEM);
+ }
+
+ for (i = 0; i < num_parents; i++) {
+ clk->reg_sel[i] = reg_sel[i];
+ clk->reg_bits[i] = reg_bits[i];
+ clk->reg_mask[i] = reg_mask[i];
+ }
+
+ clk->parent_index = 0;
+ clk->rate = rate;
+ clk->enable_delay_us = enable_delay_us;
+ clk->dev = dev;
+
+ clk_sysctrl_init.name = name;
+ clk_sysctrl_init.ops = clk_sysctrl_ops;
+ clk_sysctrl_init.flags = flags;
+ clk_sysctrl_init.parent_names = parent_names;
+ clk_sysctrl_init.num_parents = num_parents;
+ clk->hw.init = &clk_sysctrl_init;
+
+ clk_reg = devm_clk_register(clk->dev, &clk->hw);
+ if (IS_ERR_OR_NULL(clk_reg)) {
+ dev_err(dev, "clk_sysctrl: clk_register failed\n");
+ return ERR_PTR(-ENOMEM);
+ }
+
+ return clk_reg;
+}
+
+struct clk *clk_reg_sysctrl_gate(struct device *dev,
+ const char *name,
+ const char *parent_name,
+ u16 reg_sel,
+ u8 reg_mask,
+ u8 reg_bits,
+ unsigned long enable_delay_us,
+ unsigned long flags)
+{
+ const char **parent_names = (parent_name ? &parent_name : NULL);
+ u8 num_parents = (parent_name ? 1 : 0);
+
+ return clk_reg_sysctrl(dev, name, parent_names, num_parents,
+ ®_sel, ®_mask, ®_bits, 0, enable_delay_us,
+ flags, &clk_sysctrl_gate_ops);
+}
+
+struct clk *clk_reg_sysctrl_gate_fixed_rate(struct device *dev,
+ const char *name,
+ const char *parent_name,
+ u16 reg_sel,
+ u8 reg_mask,
+ u8 reg_bits,
+ unsigned long rate,
+ unsigned long enable_delay_us,
+ unsigned long flags)
+{
+ const char **parent_names = (parent_name ? &parent_name : NULL);
+ u8 num_parents = (parent_name ? 1 : 0);
+
+ return clk_reg_sysctrl(dev, name, parent_names, num_parents,
+ ®_sel, ®_mask, ®_bits,
+ rate, enable_delay_us, flags,
+ &clk_sysctrl_gate_fixed_rate_ops);
+}
+
+struct clk *clk_reg_sysctrl_set_parent(struct device *dev,
+ const char *name,
+ const char **parent_names,
+ u8 num_parents,
+ u16 *reg_sel,
+ u8 *reg_mask,
+ u8 *reg_bits,
+ unsigned long flags)
+{
+ return clk_reg_sysctrl(dev, name, parent_names, num_parents,
+ reg_sel, reg_mask, reg_bits, 0, 0, flags,
+ &clk_sysctrl_set_parent_ops);
+}
diff --git a/drivers/clk/ux500/clk.h b/drivers/clk/ux500/clk.h
index c3e4491..3d2dfdc 100644
--- a/drivers/clk/ux500/clk.h
+++ b/drivers/clk/ux500/clk.h
@@ -11,6 +11,7 @@
#define __UX500_CLK_H
#include <linux/clk.h>
+#include <linux/device.h>
struct clk *clk_reg_prcc_pclk(const char *name,
const char *parent_name,
@@ -57,4 +58,32 @@ struct clk *clk_reg_prcmu_opp_volt_scalable(const char *name,
unsigned long rate,
unsigned long flags);
+struct clk *clk_reg_sysctrl_gate(struct device *dev,
+ const char *name,
+ const char *parent_name,
+ u16 reg_sel,
+ u8 reg_mask,
+ u8 reg_bits,
+ unsigned long enable_delay_us,
+ unsigned long flags);
+
+struct clk *clk_reg_sysctrl_gate_fixed_rate(struct device *dev,
+ const char *name,
+ const char *parent_name,
+ u16 reg_sel,
+ u8 reg_mask,
+ u8 reg_bits,
+ unsigned long rate,
+ unsigned long enable_delay_us,
+ unsigned long flags);
+
+struct clk *clk_reg_sysctrl_set_parent(struct device *dev,
+ const char *name,
+ const char **parent_names,
+ u8 num_parents,
+ u16 *reg_sel,
+ u8 *reg_mask,
+ u8 *reg_bits,
+ unsigned long flags);
+
#endif /* __UX500_CLK_H */
--
1.7.10
More information about the linux-arm-kernel
mailing list