diff options
author | Shawn Guo <shawn.guo@linaro.org> | 2012-04-28 16:02:34 (GMT) |
---|---|---|
committer | Shawn Guo <shawn.guo@linaro.org> | 2012-05-08 16:02:35 (GMT) |
commit | 23b5e15a2994fb0c1444f92b76f09a482f32843c (patch) | |
tree | 54695e5b39977bd1ed04dfd945c9052a85b57e0f /drivers/clk/mxs/clk-pll.c | |
parent | d48b97b403d23f6df0b990cee652bdf9a52337a3 (diff) | |
download | linux-fsl-qoriq-23b5e15a2994fb0c1444f92b76f09a482f32843c.tar.xz |
clk: mxs: add mxs specific clocks
Add mxs specific clocks, pll, reference clock (PFD), integer divider
and fractional divider.
Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Diffstat (limited to 'drivers/clk/mxs/clk-pll.c')
-rw-r--r-- | drivers/clk/mxs/clk-pll.c | 116 |
1 files changed, 116 insertions, 0 deletions
diff --git a/drivers/clk/mxs/clk-pll.c b/drivers/clk/mxs/clk-pll.c new file mode 100644 index 0000000..fadae41 --- /dev/null +++ b/drivers/clk/mxs/clk-pll.c @@ -0,0 +1,116 @@ +/* + * Copyright 2012 Freescale Semiconductor, Inc. + * + * The code contained herein is licensed under the GNU General Public + * License. You may obtain a copy of the GNU General Public License + * Version 2 or later at the following locations: + * + * http://www.opensource.org/licenses/gpl-license.html + * http://www.gnu.org/copyleft/gpl.html + */ + +#include <linux/clk.h> +#include <linux/clk-provider.h> +#include <linux/delay.h> +#include <linux/err.h> +#include <linux/io.h> +#include <linux/slab.h> +#include "clk.h" + +/** + * struct clk_pll - mxs pll clock + * @hw: clk_hw for the pll + * @base: base address of the pll + * @power: the shift of power bit + * @rate: the clock rate of the pll + * + * The mxs pll is a fixed rate clock with power and gate control, + * and the shift of gate bit is always 31. + */ +struct clk_pll { + struct clk_hw hw; + void __iomem *base; + u8 power; + unsigned long rate; +}; + +#define to_clk_pll(_hw) container_of(_hw, struct clk_pll, hw) + +static int clk_pll_prepare(struct clk_hw *hw) +{ + struct clk_pll *pll = to_clk_pll(hw); + + writel_relaxed(1 << pll->power, pll->base + SET); + + udelay(10); + + return 0; +} + +static void clk_pll_unprepare(struct clk_hw *hw) +{ + struct clk_pll *pll = to_clk_pll(hw); + + writel_relaxed(1 << pll->power, pll->base + CLR); +} + +static int clk_pll_enable(struct clk_hw *hw) +{ + struct clk_pll *pll = to_clk_pll(hw); + + writel_relaxed(1 << 31, pll->base + CLR); + + return 0; +} + +static void clk_pll_disable(struct clk_hw *hw) +{ + struct clk_pll *pll = to_clk_pll(hw); + + writel_relaxed(1 << 31, pll->base + SET); +} + +static unsigned long clk_pll_recalc_rate(struct clk_hw *hw, + unsigned long parent_rate) +{ + struct clk_pll *pll = to_clk_pll(hw); + + return pll->rate; +} + +static const struct clk_ops clk_pll_ops = { + .prepare = clk_pll_prepare, + .unprepare = clk_pll_unprepare, + .enable = clk_pll_enable, + .disable = clk_pll_disable, + .recalc_rate = clk_pll_recalc_rate, +}; + +struct clk *mxs_clk_pll(const char *name, const char *parent_name, + void __iomem *base, u8 power, unsigned long rate) +{ + struct clk_pll *pll; + struct clk *clk; + struct clk_init_data init; + + pll = kzalloc(sizeof(*pll), GFP_KERNEL); + if (!pll) + return ERR_PTR(-ENOMEM); + + init.name = name; + init.ops = &clk_pll_ops; + init.flags = 0; + init.parent_names = (parent_name ? &parent_name: NULL); + init.num_parents = (parent_name ? 1 : 0); + + pll->base = base; + pll->rate = rate; + pll->power = power; + pll->hw.init = &init; + + clk = clk_register(NULL, &pll->hw); + if (IS_ERR(clk)) + kfree(pll); + + return clk; +} |