diff options
author | Shawn Guo <shawn.guo@linaro.org> | 2015-04-26 21:54:29 +0800 |
---|---|---|
committer | Shawn Guo <shawn.guo@linaro.org> | 2015-06-03 14:44:33 +0800 |
commit | 11f68120095d6040abd2eb37bf21bb9450646304 (patch) | |
tree | 3fcf81cd9661d6f1771a4f542deb9d01b2f0aa5d /drivers/clk/imx/clk-gate2.c | |
parent | 0c831317e77b55612ffa1b402b262983bc7001d2 (diff) |
ARM: imx: move clock drivers into drivers/clk
After the cleanup on clock drivers, they are now ready to be moved into
drivers/clk. Let's move them into drivers/clk/imx folder.
Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Acked-by: Stephen Boyd <sboyd@codeaurora.org>
Diffstat (limited to 'drivers/clk/imx/clk-gate2.c')
-rw-r--r-- | drivers/clk/imx/clk-gate2.c | 160 |
1 files changed, 160 insertions, 0 deletions
diff --git a/drivers/clk/imx/clk-gate2.c b/drivers/clk/imx/clk-gate2.c new file mode 100644 index 000000000000..8935bff99fe7 --- /dev/null +++ b/drivers/clk/imx/clk-gate2.c @@ -0,0 +1,160 @@ +/* + * Copyright (C) 2010-2011 Canonical Ltd <jeremy.kerr@canonical.com> + * Copyright (C) 2011-2012 Mike Turquette, Linaro Ltd <mturquette@linaro.org> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * Gated clock implementation + */ + +#include <linux/clk-provider.h> +#include <linux/module.h> +#include <linux/slab.h> +#include <linux/io.h> +#include <linux/err.h> +#include <linux/string.h> +#include "clk.h" + +/** + * DOC: basic gatable clock which can gate and ungate it's ouput + * + * Traits of this clock: + * prepare - clk_(un)prepare only ensures parent is (un)prepared + * enable - clk_enable and clk_disable are functional & control gating + * rate - inherits rate from parent. No clk_set_rate support + * parent - fixed parent. No clk_set_parent support + */ + +struct clk_gate2 { + struct clk_hw hw; + void __iomem *reg; + u8 bit_idx; + u8 flags; + spinlock_t *lock; + unsigned int *share_count; +}; + +#define to_clk_gate2(_hw) container_of(_hw, struct clk_gate2, hw) + +static int clk_gate2_enable(struct clk_hw *hw) +{ + struct clk_gate2 *gate = to_clk_gate2(hw); + u32 reg; + unsigned long flags = 0; + + spin_lock_irqsave(gate->lock, flags); + + if (gate->share_count && (*gate->share_count)++ > 0) + goto out; + + reg = readl(gate->reg); + reg |= 3 << gate->bit_idx; + writel(reg, gate->reg); + +out: + spin_unlock_irqrestore(gate->lock, flags); + + return 0; +} + +static void clk_gate2_disable(struct clk_hw *hw) +{ + struct clk_gate2 *gate = to_clk_gate2(hw); + u32 reg; + unsigned long flags = 0; + + spin_lock_irqsave(gate->lock, flags); + + if (gate->share_count) { + if (WARN_ON(*gate->share_count == 0)) + goto out; + else if (--(*gate->share_count) > 0) + goto out; + } + + reg = readl(gate->reg); + reg &= ~(3 << gate->bit_idx); + writel(reg, gate->reg); + +out: + spin_unlock_irqrestore(gate->lock, flags); +} + +static int clk_gate2_reg_is_enabled(void __iomem *reg, u8 bit_idx) +{ + u32 val = readl(reg); + + if (((val >> bit_idx) & 1) == 1) + return 1; + + return 0; +} + +static int clk_gate2_is_enabled(struct clk_hw *hw) +{ + struct clk_gate2 *gate = to_clk_gate2(hw); + + return clk_gate2_reg_is_enabled(gate->reg, gate->bit_idx); +} + +static void clk_gate2_disable_unused(struct clk_hw *hw) +{ + struct clk_gate2 *gate = to_clk_gate2(hw); + unsigned long flags = 0; + u32 reg; + + spin_lock_irqsave(gate->lock, flags); + + if (!gate->share_count || *gate->share_count == 0) { + reg = readl(gate->reg); + reg &= ~(3 << gate->bit_idx); + writel(reg, gate->reg); + } + + spin_unlock_irqrestore(gate->lock, flags); +} + +static struct clk_ops clk_gate2_ops = { + .enable = clk_gate2_enable, + .disable = clk_gate2_disable, + .disable_unused = clk_gate2_disable_unused, + .is_enabled = clk_gate2_is_enabled, +}; + +struct clk *clk_register_gate2(struct device *dev, const char *name, + const char *parent_name, unsigned long flags, + void __iomem *reg, u8 bit_idx, + u8 clk_gate2_flags, spinlock_t *lock, + unsigned int *share_count) +{ + struct clk_gate2 *gate; + struct clk *clk; + struct clk_init_data init; + + gate = kzalloc(sizeof(struct clk_gate2), GFP_KERNEL); + if (!gate) + return ERR_PTR(-ENOMEM); + + /* struct clk_gate2 assignments */ + gate->reg = reg; + gate->bit_idx = bit_idx; + gate->flags = clk_gate2_flags; + gate->lock = lock; + gate->share_count = share_count; + + init.name = name; + init.ops = &clk_gate2_ops; + init.flags = flags; + init.parent_names = parent_name ? &parent_name : NULL; + init.num_parents = parent_name ? 1 : 0; + + gate->hw.init = &init; + + clk = clk_register(dev, &gate->hw); + if (IS_ERR(clk)) + kfree(gate); + + return clk; +} |