From mboxrd@z Thu Jan 1 00:00:00 1970 From: jeremy.kerr@canonical.com (Jeremy Kerr) Date: Fri, 20 May 2011 15:27:49 +0800 Subject: [PATCH 4/4] clk: Add simple gated clock In-Reply-To: <1305876469.325655.313573683829.0.gpush@pororo> Message-ID: <1305876469.327589.409938867568.4.gpush@pororo> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org Signed-off-by: Jeremy Kerr --- drivers/clk/Kconfig | 4 ++++ drivers/clk/Makefile | 1 + drivers/clk/clk-gate.c | 41 +++++++++++++++++++++++++++++++++++++++++ include/linux/clk.h | 13 +++++++++++++ 4 files changed, 59 insertions(+) diff --git a/drivers/clk/Kconfig b/drivers/clk/Kconfig index 0a27963..75d2902 100644 --- a/drivers/clk/Kconfig +++ b/drivers/clk/Kconfig @@ -9,3 +9,7 @@ config GENERIC_CLK config GENERIC_CLK_FIXED bool depends on GENERIC_CLK + +config GENERIC_CLK_GATE + bool + depends on GENERIC_CLK diff --git a/drivers/clk/Makefile b/drivers/clk/Makefile index 9a3325a..d186446 100644 --- a/drivers/clk/Makefile +++ b/drivers/clk/Makefile @@ -2,3 +2,4 @@ obj-$(CONFIG_CLKDEV_LOOKUP) += clkdev.o obj-$(CONFIG_GENERIC_CLK) += clk.o obj-$(CONFIG_GENERIC_CLK_FIXED) += clk-fixed.o +obj-$(CONFIG_GENERIC_CLK_GATE) += clk-gate.o diff --git a/drivers/clk/clk-gate.c b/drivers/clk/clk-gate.c new file mode 100644 index 0000000..833e0da --- /dev/null +++ b/drivers/clk/clk-gate.c @@ -0,0 +1,41 @@ + +#include +#include +#include + +#define to_clk_gate(clk) container_of(clk, struct clk_gate, hw) + +static unsigned long clk_gate_get_rate(struct clk_hw *clk) +{ + return clk_get_rate(clk_get_parent(clk->clk)); +} + +static int clk_gate_enable(struct clk_hw *clk) +{ + struct clk_gate *gate = to_clk_gate(clk); + u32 reg; + + reg = __raw_readl(gate->reg); + reg |= 1 << gate->bit_idx; + __raw_writel(reg, gate->reg); + + return 0; +} + +static void clk_gate_disable(struct clk_hw *clk) +{ + struct clk_gate *gate = to_clk_gate(clk); + u32 reg; + + reg = __raw_readl(gate->reg); + reg &= ~(1 << gate->bit_idx); + __raw_writel(reg, gate->reg); +} + +struct clk_hw_ops clk_gate_ops = { + .recalc_rate = clk_gate_get_rate, + .enable = clk_gate_enable, + .disable = clk_gate_disable, +}; +EXPORT_SYMBOL_GPL(clk_gate_ops); + diff --git a/include/linux/clk.h b/include/linux/clk.h index fd62e86..7c26135 100644 --- a/include/linux/clk.h +++ b/include/linux/clk.h @@ -124,6 +124,19 @@ extern struct clk_hw_ops clk_fixed_ops; #endif /* CONFIG_GENERIC_CLK_FIXED */ +#ifdef CONFIG_GENERIC_CLK_GATE + +struct clk_gate { + struct clk_hw hw; + void __iomem *reg; + u8 bit_idx; +}; + +extern struct clk_hw_ops clk_gate_ops; + +#endif /* CONFIG_GENERIC_CLK_GATE */ + + #else /* !CONFIG_GENERIC_CLK */ /*