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-rw-r--r--drivers/clk/at91/clk-smd.c137
1 files changed, 137 insertions, 0 deletions
diff --git a/drivers/clk/at91/clk-smd.c b/drivers/clk/at91/clk-smd.c
new file mode 100644
index 000000000..160378438
--- /dev/null
+++ b/drivers/clk/at91/clk-smd.c
@@ -0,0 +1,137 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (C) 2013 Boris BREZILLON <b.brezillon@overkiz.com>
+ */
+
+#include <linux/clk-provider.h>
+#include <linux/clkdev.h>
+#include <linux/clk/at91_pmc.h>
+#include <linux/of.h>
+#include <linux/mfd/syscon.h>
+#include <linux/regmap.h>
+
+#include "pmc.h"
+
+#define SMD_DIV_SHIFT 8
+#define SMD_MAX_DIV 0xf
+
+struct at91sam9x5_clk_smd {
+ struct clk_hw hw;
+ struct regmap *regmap;
+};
+
+#define to_at91sam9x5_clk_smd(hw) \
+ container_of(hw, struct at91sam9x5_clk_smd, hw)
+
+static unsigned long at91sam9x5_clk_smd_recalc_rate(struct clk_hw *hw,
+ unsigned long parent_rate)
+{
+ struct at91sam9x5_clk_smd *smd = to_at91sam9x5_clk_smd(hw);
+ unsigned int smdr;
+ u8 smddiv;
+
+ regmap_read(smd->regmap, AT91_PMC_SMD, &smdr);
+ smddiv = (smdr & AT91_PMC_SMD_DIV) >> SMD_DIV_SHIFT;
+
+ return parent_rate / (smddiv + 1);
+}
+
+static long at91sam9x5_clk_smd_round_rate(struct clk_hw *hw, unsigned long rate,
+ unsigned long *parent_rate)
+{
+ unsigned long div;
+ unsigned long bestrate;
+ unsigned long tmp;
+
+ if (rate >= *parent_rate)
+ return *parent_rate;
+
+ div = *parent_rate / rate;
+ if (div > SMD_MAX_DIV)
+ return *parent_rate / (SMD_MAX_DIV + 1);
+
+ bestrate = *parent_rate / div;
+ tmp = *parent_rate / (div + 1);
+ if (bestrate - rate > rate - tmp)
+ bestrate = tmp;
+
+ return bestrate;
+}
+
+static int at91sam9x5_clk_smd_set_parent(struct clk_hw *hw, u8 index)
+{
+ struct at91sam9x5_clk_smd *smd = to_at91sam9x5_clk_smd(hw);
+
+ if (index > 1)
+ return -EINVAL;
+
+ regmap_update_bits(smd->regmap, AT91_PMC_SMD, AT91_PMC_SMDS,
+ index ? AT91_PMC_SMDS : 0);
+
+ return 0;
+}
+
+static u8 at91sam9x5_clk_smd_get_parent(struct clk_hw *hw)
+{
+ struct at91sam9x5_clk_smd *smd = to_at91sam9x5_clk_smd(hw);
+ unsigned int smdr;
+
+ regmap_read(smd->regmap, AT91_PMC_SMD, &smdr);
+
+ return smdr & AT91_PMC_SMDS;
+}
+
+static int at91sam9x5_clk_smd_set_rate(struct clk_hw *hw, unsigned long rate,
+ unsigned long parent_rate)
+{
+ struct at91sam9x5_clk_smd *smd = to_at91sam9x5_clk_smd(hw);
+ unsigned long div = parent_rate / rate;
+
+ if (parent_rate % rate || div < 1 || div > (SMD_MAX_DIV + 1))
+ return -EINVAL;
+
+ regmap_update_bits(smd->regmap, AT91_PMC_SMD, AT91_PMC_SMD_DIV,
+ (div - 1) << SMD_DIV_SHIFT);
+
+ return 0;
+}
+
+static const struct clk_ops at91sam9x5_smd_ops = {
+ .recalc_rate = at91sam9x5_clk_smd_recalc_rate,
+ .round_rate = at91sam9x5_clk_smd_round_rate,
+ .get_parent = at91sam9x5_clk_smd_get_parent,
+ .set_parent = at91sam9x5_clk_smd_set_parent,
+ .set_rate = at91sam9x5_clk_smd_set_rate,
+};
+
+struct clk_hw * __init
+at91sam9x5_clk_register_smd(struct regmap *regmap, const char *name,
+ const char **parent_names, u8 num_parents)
+{
+ struct at91sam9x5_clk_smd *smd;
+ struct clk_hw *hw;
+ struct clk_init_data init;
+ int ret;
+
+ smd = kzalloc(sizeof(*smd), GFP_KERNEL);
+ if (!smd)
+ return ERR_PTR(-ENOMEM);
+
+ init.name = name;
+ init.ops = &at91sam9x5_smd_ops;
+ init.parent_names = parent_names;
+ init.num_parents = num_parents;
+ init.flags = CLK_SET_RATE_GATE | CLK_SET_PARENT_GATE;
+
+ smd->hw.init = &init;
+ smd->regmap = regmap;
+
+ hw = &smd->hw;
+ ret = clk_hw_register(NULL, &smd->hw);
+ if (ret) {
+ kfree(smd);
+ hw = ERR_PTR(ret);
+ }
+
+ return hw;
+}