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path: root/drivers/clk/nuvoton/clk-ma35d1-divider.c
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Diffstat (limited to 'drivers/clk/nuvoton/clk-ma35d1-divider.c')
-rw-r--r--drivers/clk/nuvoton/clk-ma35d1-divider.c132
1 files changed, 132 insertions, 0 deletions
diff --git a/drivers/clk/nuvoton/clk-ma35d1-divider.c b/drivers/clk/nuvoton/clk-ma35d1-divider.c
new file mode 100644
index 000000000000..bb8c23d2b895
--- /dev/null
+++ b/drivers/clk/nuvoton/clk-ma35d1-divider.c
@@ -0,0 +1,132 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2023 Nuvoton Technology Corp.
+ * Author: Chi-Fang Li <cfli0@nuvoton.com>
+ */
+
+#include <linux/clk-provider.h>
+#include <linux/device.h>
+#include <linux/regmap.h>
+#include <linux/spinlock.h>
+
+#include "clk-ma35d1.h"
+
+struct ma35d1_adc_clk_div {
+ struct clk_hw hw;
+ void __iomem *reg;
+ u8 shift;
+ u8 width;
+ u32 mask;
+ const struct clk_div_table *table;
+ /* protects concurrent access to clock divider registers */
+ spinlock_t *lock;
+};
+
+static inline struct ma35d1_adc_clk_div *to_ma35d1_adc_clk_div(struct clk_hw *_hw)
+{
+ return container_of(_hw, struct ma35d1_adc_clk_div, hw);
+}
+
+static unsigned long ma35d1_clkdiv_recalc_rate(struct clk_hw *hw, unsigned long parent_rate)
+{
+ unsigned int val;
+ struct ma35d1_adc_clk_div *dclk = to_ma35d1_adc_clk_div(hw);
+
+ val = readl_relaxed(dclk->reg) >> dclk->shift;
+ val &= clk_div_mask(dclk->width);
+ val += 1;
+ return divider_recalc_rate(hw, parent_rate, val, dclk->table,
+ CLK_DIVIDER_ROUND_CLOSEST, dclk->width);
+}
+
+static long ma35d1_clkdiv_round_rate(struct clk_hw *hw, unsigned long rate, unsigned long *prate)
+{
+ struct ma35d1_adc_clk_div *dclk = to_ma35d1_adc_clk_div(hw);
+
+ return divider_round_rate(hw, rate, prate, dclk->table,
+ dclk->width, CLK_DIVIDER_ROUND_CLOSEST);
+}
+
+static int ma35d1_clkdiv_set_rate(struct clk_hw *hw, unsigned long rate, unsigned long parent_rate)
+{
+ int value;
+ unsigned long flags = 0;
+ u32 data;
+ struct ma35d1_adc_clk_div *dclk = to_ma35d1_adc_clk_div(hw);
+
+ value = divider_get_val(rate, parent_rate, dclk->table,
+ dclk->width, CLK_DIVIDER_ROUND_CLOSEST);
+
+ spin_lock_irqsave(dclk->lock, flags);
+
+ data = readl_relaxed(dclk->reg);
+ data &= ~(clk_div_mask(dclk->width) << dclk->shift);
+ data |= (value - 1) << dclk->shift;
+ data |= dclk->mask;
+ writel_relaxed(data, dclk->reg);
+
+ spin_unlock_irqrestore(dclk->lock, flags);
+ return 0;
+}
+
+static const struct clk_ops ma35d1_adc_clkdiv_ops = {
+ .recalc_rate = ma35d1_clkdiv_recalc_rate,
+ .round_rate = ma35d1_clkdiv_round_rate,
+ .set_rate = ma35d1_clkdiv_set_rate,
+};
+
+struct clk_hw *ma35d1_reg_adc_clkdiv(struct device *dev, const char *name,
+ struct clk_hw *parent_hw, spinlock_t *lock,
+ unsigned long flags, void __iomem *reg,
+ u8 shift, u8 width, u32 mask_bit)
+{
+ struct ma35d1_adc_clk_div *div;
+ struct clk_init_data init;
+ struct clk_div_table *table;
+ struct clk_parent_data pdata = { .index = 0 };
+ u32 max_div, min_div;
+ struct clk_hw *hw;
+ int ret;
+ int i;
+
+ div = devm_kzalloc(dev, sizeof(*div), GFP_KERNEL);
+ if (!div)
+ return ERR_PTR(-ENOMEM);
+
+ max_div = clk_div_mask(width) + 1;
+ min_div = 1;
+
+ table = devm_kcalloc(dev, max_div + 1, sizeof(*table), GFP_KERNEL);
+ if (!table)
+ return ERR_PTR(-ENOMEM);
+
+ for (i = 0; i < max_div; i++) {
+ table[i].val = min_div + i;
+ table[i].div = 2 * table[i].val;
+ }
+ table[max_div].val = 0;
+ table[max_div].div = 0;
+
+ memset(&init, 0, sizeof(init));
+ init.name = name;
+ init.ops = &ma35d1_adc_clkdiv_ops;
+ init.flags |= flags;
+ pdata.hw = parent_hw;
+ init.parent_data = &pdata;
+ init.num_parents = 1;
+
+ div->reg = reg;
+ div->shift = shift;
+ div->width = width;
+ div->mask = mask_bit ? BIT(mask_bit) : 0;
+ div->lock = lock;
+ div->hw.init = &init;
+ div->table = table;
+
+ hw = &div->hw;
+ ret = devm_clk_hw_register(dev, hw);
+ if (ret)
+ return ERR_PTR(ret);
+ return hw;
+}
+EXPORT_SYMBOL_GPL(ma35d1_reg_adc_clkdiv);