494 lines
13 KiB
C
494 lines
13 KiB
C
// SPDX-License-Identifier: GPL-2.0
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/*
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* JZ47xx SoCs TCU clocks driver
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* Copyright (C) 2019 Paul Cercueil <paul@crapouillou.net>
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*/
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#include <linux/clk.h>
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#include <linux/clk-provider.h>
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#include <linux/clockchips.h>
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#include <linux/mfd/ingenic-tcu.h>
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#include <linux/mfd/syscon.h>
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#include <linux/regmap.h>
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#include <linux/slab.h>
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#include <linux/syscore_ops.h>
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#include <dt-bindings/clock/ingenic,tcu.h>
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/* 8 channels max + watchdog + OST */
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#define TCU_CLK_COUNT 10
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#undef pr_fmt
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#define pr_fmt(fmt) "ingenic-tcu-clk: " fmt
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enum tcu_clk_parent {
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TCU_PARENT_PCLK,
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TCU_PARENT_RTC,
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TCU_PARENT_EXT,
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};
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struct ingenic_soc_info {
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unsigned int num_channels;
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bool has_ost;
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bool has_tcu_clk;
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bool allow_missing_tcu_clk;
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};
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struct ingenic_tcu_clk_info {
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struct clk_init_data init_data;
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u8 gate_bit;
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u8 tcsr_reg;
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};
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struct ingenic_tcu_clk {
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struct clk_hw hw;
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unsigned int idx;
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struct ingenic_tcu *tcu;
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const struct ingenic_tcu_clk_info *info;
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};
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struct ingenic_tcu {
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const struct ingenic_soc_info *soc_info;
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struct regmap *map;
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struct clk *clk;
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struct clk_hw_onecell_data *clocks;
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};
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static struct ingenic_tcu *ingenic_tcu;
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static inline struct ingenic_tcu_clk *to_tcu_clk(struct clk_hw *hw)
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{
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return container_of(hw, struct ingenic_tcu_clk, hw);
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}
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static int ingenic_tcu_enable(struct clk_hw *hw)
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{
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struct ingenic_tcu_clk *tcu_clk = to_tcu_clk(hw);
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const struct ingenic_tcu_clk_info *info = tcu_clk->info;
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struct ingenic_tcu *tcu = tcu_clk->tcu;
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regmap_write(tcu->map, TCU_REG_TSCR, BIT(info->gate_bit));
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return 0;
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}
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static void ingenic_tcu_disable(struct clk_hw *hw)
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{
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struct ingenic_tcu_clk *tcu_clk = to_tcu_clk(hw);
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const struct ingenic_tcu_clk_info *info = tcu_clk->info;
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struct ingenic_tcu *tcu = tcu_clk->tcu;
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regmap_write(tcu->map, TCU_REG_TSSR, BIT(info->gate_bit));
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}
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static int ingenic_tcu_is_enabled(struct clk_hw *hw)
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{
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struct ingenic_tcu_clk *tcu_clk = to_tcu_clk(hw);
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const struct ingenic_tcu_clk_info *info = tcu_clk->info;
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unsigned int value;
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regmap_read(tcu_clk->tcu->map, TCU_REG_TSR, &value);
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return !(value & BIT(info->gate_bit));
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}
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static bool ingenic_tcu_enable_regs(struct clk_hw *hw)
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{
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struct ingenic_tcu_clk *tcu_clk = to_tcu_clk(hw);
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const struct ingenic_tcu_clk_info *info = tcu_clk->info;
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struct ingenic_tcu *tcu = tcu_clk->tcu;
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bool enabled = false;
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/*
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* According to the programming manual, a timer channel's registers can
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* only be accessed when the channel's stop bit is clear.
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*/
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enabled = !!ingenic_tcu_is_enabled(hw);
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regmap_write(tcu->map, TCU_REG_TSCR, BIT(info->gate_bit));
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return enabled;
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}
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static void ingenic_tcu_disable_regs(struct clk_hw *hw)
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{
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struct ingenic_tcu_clk *tcu_clk = to_tcu_clk(hw);
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const struct ingenic_tcu_clk_info *info = tcu_clk->info;
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struct ingenic_tcu *tcu = tcu_clk->tcu;
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regmap_write(tcu->map, TCU_REG_TSSR, BIT(info->gate_bit));
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}
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static u8 ingenic_tcu_get_parent(struct clk_hw *hw)
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{
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struct ingenic_tcu_clk *tcu_clk = to_tcu_clk(hw);
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const struct ingenic_tcu_clk_info *info = tcu_clk->info;
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unsigned int val = 0;
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int ret;
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ret = regmap_read(tcu_clk->tcu->map, info->tcsr_reg, &val);
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WARN_ONCE(ret < 0, "Unable to read TCSR %d", tcu_clk->idx);
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return ffs(val & TCU_TCSR_PARENT_CLOCK_MASK) - 1;
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}
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static int ingenic_tcu_set_parent(struct clk_hw *hw, u8 idx)
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{
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struct ingenic_tcu_clk *tcu_clk = to_tcu_clk(hw);
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const struct ingenic_tcu_clk_info *info = tcu_clk->info;
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bool was_enabled;
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int ret;
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was_enabled = ingenic_tcu_enable_regs(hw);
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ret = regmap_update_bits(tcu_clk->tcu->map, info->tcsr_reg,
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TCU_TCSR_PARENT_CLOCK_MASK, BIT(idx));
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WARN_ONCE(ret < 0, "Unable to update TCSR %d", tcu_clk->idx);
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if (!was_enabled)
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ingenic_tcu_disable_regs(hw);
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return 0;
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}
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static unsigned long ingenic_tcu_recalc_rate(struct clk_hw *hw,
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unsigned long parent_rate)
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{
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struct ingenic_tcu_clk *tcu_clk = to_tcu_clk(hw);
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const struct ingenic_tcu_clk_info *info = tcu_clk->info;
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unsigned int prescale;
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int ret;
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ret = regmap_read(tcu_clk->tcu->map, info->tcsr_reg, &prescale);
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WARN_ONCE(ret < 0, "Unable to read TCSR %d", tcu_clk->idx);
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prescale = (prescale & TCU_TCSR_PRESCALE_MASK) >> TCU_TCSR_PRESCALE_LSB;
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return parent_rate >> (prescale * 2);
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}
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static u8 ingenic_tcu_get_prescale(unsigned long rate, unsigned long req_rate)
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{
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u8 prescale;
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for (prescale = 0; prescale < 5; prescale++)
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if ((rate >> (prescale * 2)) <= req_rate)
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return prescale;
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return 5; /* /1024 divider */
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}
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static long ingenic_tcu_round_rate(struct clk_hw *hw, unsigned long req_rate,
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unsigned long *parent_rate)
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{
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unsigned long rate = *parent_rate;
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u8 prescale;
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if (req_rate > rate)
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return rate;
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prescale = ingenic_tcu_get_prescale(rate, req_rate);
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return rate >> (prescale * 2);
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}
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static int ingenic_tcu_set_rate(struct clk_hw *hw, unsigned long req_rate,
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unsigned long parent_rate)
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{
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struct ingenic_tcu_clk *tcu_clk = to_tcu_clk(hw);
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const struct ingenic_tcu_clk_info *info = tcu_clk->info;
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u8 prescale = ingenic_tcu_get_prescale(parent_rate, req_rate);
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bool was_enabled;
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int ret;
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was_enabled = ingenic_tcu_enable_regs(hw);
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ret = regmap_update_bits(tcu_clk->tcu->map, info->tcsr_reg,
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TCU_TCSR_PRESCALE_MASK,
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prescale << TCU_TCSR_PRESCALE_LSB);
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WARN_ONCE(ret < 0, "Unable to update TCSR %d", tcu_clk->idx);
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if (!was_enabled)
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ingenic_tcu_disable_regs(hw);
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return 0;
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}
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static const struct clk_ops ingenic_tcu_clk_ops = {
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.get_parent = ingenic_tcu_get_parent,
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.set_parent = ingenic_tcu_set_parent,
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.recalc_rate = ingenic_tcu_recalc_rate,
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.round_rate = ingenic_tcu_round_rate,
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.set_rate = ingenic_tcu_set_rate,
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.enable = ingenic_tcu_enable,
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.disable = ingenic_tcu_disable,
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.is_enabled = ingenic_tcu_is_enabled,
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};
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static const char * const ingenic_tcu_timer_parents[] = {
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[TCU_PARENT_PCLK] = "pclk",
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[TCU_PARENT_RTC] = "rtc",
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[TCU_PARENT_EXT] = "ext",
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};
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#define DEF_TIMER(_name, _gate_bit, _tcsr) \
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{ \
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.init_data = { \
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.name = _name, \
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.parent_names = ingenic_tcu_timer_parents, \
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.num_parents = ARRAY_SIZE(ingenic_tcu_timer_parents),\
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.ops = &ingenic_tcu_clk_ops, \
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.flags = CLK_SET_RATE_UNGATE, \
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}, \
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.gate_bit = _gate_bit, \
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.tcsr_reg = _tcsr, \
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}
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static const struct ingenic_tcu_clk_info ingenic_tcu_clk_info[] = {
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[TCU_CLK_TIMER0] = DEF_TIMER("timer0", 0, TCU_REG_TCSRc(0)),
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[TCU_CLK_TIMER1] = DEF_TIMER("timer1", 1, TCU_REG_TCSRc(1)),
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[TCU_CLK_TIMER2] = DEF_TIMER("timer2", 2, TCU_REG_TCSRc(2)),
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[TCU_CLK_TIMER3] = DEF_TIMER("timer3", 3, TCU_REG_TCSRc(3)),
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[TCU_CLK_TIMER4] = DEF_TIMER("timer4", 4, TCU_REG_TCSRc(4)),
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[TCU_CLK_TIMER5] = DEF_TIMER("timer5", 5, TCU_REG_TCSRc(5)),
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[TCU_CLK_TIMER6] = DEF_TIMER("timer6", 6, TCU_REG_TCSRc(6)),
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[TCU_CLK_TIMER7] = DEF_TIMER("timer7", 7, TCU_REG_TCSRc(7)),
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};
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static const struct ingenic_tcu_clk_info ingenic_tcu_watchdog_clk_info =
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DEF_TIMER("wdt", 16, TCU_REG_WDT_TCSR);
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static const struct ingenic_tcu_clk_info ingenic_tcu_ost_clk_info =
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DEF_TIMER("ost", 15, TCU_REG_OST_TCSR);
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#undef DEF_TIMER
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static int __init ingenic_tcu_register_clock(struct ingenic_tcu *tcu,
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unsigned int idx, enum tcu_clk_parent parent,
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const struct ingenic_tcu_clk_info *info,
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struct clk_hw_onecell_data *clocks)
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{
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struct ingenic_tcu_clk *tcu_clk;
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int err;
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tcu_clk = kzalloc(sizeof(*tcu_clk), GFP_KERNEL);
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if (!tcu_clk)
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return -ENOMEM;
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tcu_clk->hw.init = &info->init_data;
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tcu_clk->idx = idx;
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tcu_clk->info = info;
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tcu_clk->tcu = tcu;
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/* Reset channel and clock divider, set default parent */
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ingenic_tcu_enable_regs(&tcu_clk->hw);
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regmap_update_bits(tcu->map, info->tcsr_reg, 0xffff, BIT(parent));
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ingenic_tcu_disable_regs(&tcu_clk->hw);
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err = clk_hw_register(NULL, &tcu_clk->hw);
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if (err) {
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kfree(tcu_clk);
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return err;
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}
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clocks->hws[idx] = &tcu_clk->hw;
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return 0;
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}
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static const struct ingenic_soc_info jz4740_soc_info = {
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.num_channels = 8,
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.has_ost = false,
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.has_tcu_clk = true,
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};
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static const struct ingenic_soc_info jz4725b_soc_info = {
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.num_channels = 6,
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.has_ost = true,
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.has_tcu_clk = true,
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};
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static const struct ingenic_soc_info jz4770_soc_info = {
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.num_channels = 8,
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.has_ost = true,
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.has_tcu_clk = false,
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};
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static const struct ingenic_soc_info x1000_soc_info = {
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.num_channels = 8,
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.has_ost = false, /* X1000 has OST, but it not belong TCU */
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.has_tcu_clk = true,
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.allow_missing_tcu_clk = true,
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};
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static const struct of_device_id __maybe_unused ingenic_tcu_of_match[] __initconst = {
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{ .compatible = "ingenic,jz4740-tcu", .data = &jz4740_soc_info, },
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{ .compatible = "ingenic,jz4725b-tcu", .data = &jz4725b_soc_info, },
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{ .compatible = "ingenic,jz4760-tcu", .data = &jz4770_soc_info, },
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{ .compatible = "ingenic,jz4770-tcu", .data = &jz4770_soc_info, },
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{ .compatible = "ingenic,x1000-tcu", .data = &x1000_soc_info, },
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{ /* sentinel */ }
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};
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static int __init ingenic_tcu_probe(struct device_node *np)
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{
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const struct of_device_id *id = of_match_node(ingenic_tcu_of_match, np);
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struct ingenic_tcu *tcu;
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struct regmap *map;
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unsigned int i;
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int ret;
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map = device_node_to_regmap(np);
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if (IS_ERR(map))
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return PTR_ERR(map);
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tcu = kzalloc(sizeof(*tcu), GFP_KERNEL);
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if (!tcu)
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return -ENOMEM;
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tcu->map = map;
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tcu->soc_info = id->data;
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if (tcu->soc_info->has_tcu_clk) {
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tcu->clk = of_clk_get_by_name(np, "tcu");
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if (IS_ERR(tcu->clk)) {
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ret = PTR_ERR(tcu->clk);
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/*
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* Old device trees for some SoCs did not include the
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* TCU clock because this driver (incorrectly) didn't
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* use it. In this case we complain loudly and attempt
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* to continue without the clock, which might work if
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* booting with workarounds like "clk_ignore_unused".
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*/
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if (tcu->soc_info->allow_missing_tcu_clk && ret == -EINVAL) {
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pr_warn("TCU clock missing from device tree, please update your device tree\n");
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tcu->clk = NULL;
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} else {
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pr_crit("Cannot get TCU clock from device tree\n");
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goto err_free_tcu;
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}
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} else {
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ret = clk_prepare_enable(tcu->clk);
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if (ret) {
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pr_crit("Unable to enable TCU clock\n");
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goto err_put_clk;
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}
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}
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}
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tcu->clocks = kzalloc(struct_size(tcu->clocks, hws, TCU_CLK_COUNT),
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GFP_KERNEL);
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if (!tcu->clocks) {
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ret = -ENOMEM;
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goto err_clk_disable;
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}
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tcu->clocks->num = TCU_CLK_COUNT;
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for (i = 0; i < tcu->soc_info->num_channels; i++) {
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ret = ingenic_tcu_register_clock(tcu, i, TCU_PARENT_EXT,
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&ingenic_tcu_clk_info[i],
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tcu->clocks);
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if (ret) {
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pr_crit("cannot register clock %d\n", i);
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goto err_unregister_timer_clocks;
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}
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}
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/*
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* We set EXT as the default parent clock for all the TCU clocks
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* except for the watchdog one, where we set the RTC clock as the
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* parent. Since the EXT and PCLK are much faster than the RTC clock,
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* the watchdog would kick after a maximum time of 5s, and we might
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* want a slower kicking time.
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*/
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ret = ingenic_tcu_register_clock(tcu, TCU_CLK_WDT, TCU_PARENT_RTC,
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&ingenic_tcu_watchdog_clk_info,
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tcu->clocks);
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if (ret) {
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pr_crit("cannot register watchdog clock\n");
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goto err_unregister_timer_clocks;
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}
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if (tcu->soc_info->has_ost) {
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ret = ingenic_tcu_register_clock(tcu, TCU_CLK_OST,
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TCU_PARENT_EXT,
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&ingenic_tcu_ost_clk_info,
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tcu->clocks);
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if (ret) {
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pr_crit("cannot register ost clock\n");
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goto err_unregister_watchdog_clock;
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}
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}
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ret = of_clk_add_hw_provider(np, of_clk_hw_onecell_get, tcu->clocks);
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if (ret) {
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pr_crit("cannot add OF clock provider\n");
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goto err_unregister_ost_clock;
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}
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ingenic_tcu = tcu;
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return 0;
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err_unregister_ost_clock:
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if (tcu->soc_info->has_ost)
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clk_hw_unregister(tcu->clocks->hws[i + 1]);
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err_unregister_watchdog_clock:
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clk_hw_unregister(tcu->clocks->hws[i]);
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err_unregister_timer_clocks:
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for (i = 0; i < tcu->clocks->num; i++)
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if (tcu->clocks->hws[i])
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clk_hw_unregister(tcu->clocks->hws[i]);
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kfree(tcu->clocks);
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err_clk_disable:
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if (tcu->clk)
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clk_disable_unprepare(tcu->clk);
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err_put_clk:
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if (tcu->clk)
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clk_put(tcu->clk);
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err_free_tcu:
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kfree(tcu);
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return ret;
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}
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static int __maybe_unused tcu_pm_suspend(void)
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{
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struct ingenic_tcu *tcu = ingenic_tcu;
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if (tcu->clk)
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clk_disable(tcu->clk);
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return 0;
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}
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static void __maybe_unused tcu_pm_resume(void)
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{
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struct ingenic_tcu *tcu = ingenic_tcu;
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if (tcu->clk)
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clk_enable(tcu->clk);
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}
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static struct syscore_ops __maybe_unused tcu_pm_ops = {
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.suspend = tcu_pm_suspend,
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.resume = tcu_pm_resume,
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|
};
|
|
|
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static void __init ingenic_tcu_init(struct device_node *np)
|
|
{
|
|
int ret = ingenic_tcu_probe(np);
|
|
|
|
if (ret)
|
|
pr_crit("Failed to initialize TCU clocks: %d\n", ret);
|
|
|
|
if (IS_ENABLED(CONFIG_PM_SLEEP))
|
|
register_syscore_ops(&tcu_pm_ops);
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|
}
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|
|
|
CLK_OF_DECLARE_DRIVER(jz4740_cgu, "ingenic,jz4740-tcu", ingenic_tcu_init);
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|
CLK_OF_DECLARE_DRIVER(jz4725b_cgu, "ingenic,jz4725b-tcu", ingenic_tcu_init);
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|
CLK_OF_DECLARE_DRIVER(jz4760_cgu, "ingenic,jz4760-tcu", ingenic_tcu_init);
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|
CLK_OF_DECLARE_DRIVER(jz4770_cgu, "ingenic,jz4770-tcu", ingenic_tcu_init);
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|
CLK_OF_DECLARE_DRIVER(x1000_cgu, "ingenic,x1000-tcu", ingenic_tcu_init);
|