diff options
Diffstat (limited to 'drivers/clk/imx/clk-busy.c')
| -rw-r--r-- | drivers/clk/imx/clk-busy.c | 189 |
1 files changed, 189 insertions, 0 deletions
diff --git a/drivers/clk/imx/clk-busy.c b/drivers/clk/imx/clk-busy.c new file mode 100644 index 000000000..e695622c5 --- /dev/null +++ b/drivers/clk/imx/clk-busy.c @@ -0,0 +1,189 @@ +/* + * Copyright 2012 Freescale Semiconductor, Inc. + * Copyright 2012 Linaro Ltd. + * + * 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/io.h> +#include <linux/slab.h> +#include <linux/jiffies.h> +#include <linux/err.h> +#include "clk.h" + +static int clk_busy_wait(void __iomem *reg, u8 shift) +{ + unsigned long timeout = jiffies + msecs_to_jiffies(10); + + while (readl_relaxed(reg) & (1 << shift)) + if (time_after(jiffies, timeout)) + return -ETIMEDOUT; + + return 0; +} + +struct clk_busy_divider { + struct clk_divider div; + const struct clk_ops *div_ops; + void __iomem *reg; + u8 shift; +}; + +static inline struct clk_busy_divider *to_clk_busy_divider(struct clk_hw *hw) +{ + struct clk_divider *div = to_clk_divider(hw); + + return container_of(div, struct clk_busy_divider, div); +} + +static unsigned long clk_busy_divider_recalc_rate(struct clk_hw *hw, + unsigned long parent_rate) +{ + struct clk_busy_divider *busy = to_clk_busy_divider(hw); + + return busy->div_ops->recalc_rate(&busy->div.hw, parent_rate); +} + +static long clk_busy_divider_round_rate(struct clk_hw *hw, unsigned long rate, + unsigned long *prate) +{ + struct clk_busy_divider *busy = to_clk_busy_divider(hw); + + return busy->div_ops->round_rate(&busy->div.hw, rate, prate); +} + +static int clk_busy_divider_set_rate(struct clk_hw *hw, unsigned long rate, + unsigned long parent_rate) +{ + struct clk_busy_divider *busy = to_clk_busy_divider(hw); + int ret; + + ret = busy->div_ops->set_rate(&busy->div.hw, rate, parent_rate); + if (!ret) + ret = clk_busy_wait(busy->reg, busy->shift); + + return ret; +} + +static const struct clk_ops clk_busy_divider_ops = { + .recalc_rate = clk_busy_divider_recalc_rate, + .round_rate = clk_busy_divider_round_rate, + .set_rate = clk_busy_divider_set_rate, +}; + +struct clk *imx_clk_busy_divider(const char *name, const char *parent_name, + void __iomem *reg, u8 shift, u8 width, + void __iomem *busy_reg, u8 busy_shift) +{ + struct clk_busy_divider *busy; + struct clk *clk; + struct clk_init_data init; + + busy = kzalloc(sizeof(*busy), GFP_KERNEL); + if (!busy) + return ERR_PTR(-ENOMEM); + + busy->reg = busy_reg; + busy->shift = busy_shift; + + busy->div.reg = reg; + busy->div.shift = shift; + busy->div.width = width; + busy->div.lock = &imx_ccm_lock; + busy->div_ops = &clk_divider_ops; + + init.name = name; + init.ops = &clk_busy_divider_ops; + init.flags = CLK_SET_RATE_PARENT | CLK_IS_CRITICAL; + init.parent_names = &parent_name; + init.num_parents = 1; + + busy->div.hw.init = &init; + + clk = clk_register(NULL, &busy->div.hw); + if (IS_ERR(clk)) + kfree(busy); + + return clk; +} + +struct clk_busy_mux { + struct clk_mux mux; + const struct clk_ops *mux_ops; + void __iomem *reg; + u8 shift; +}; + +static inline struct clk_busy_mux *to_clk_busy_mux(struct clk_hw *hw) +{ + struct clk_mux *mux = to_clk_mux(hw); + + return container_of(mux, struct clk_busy_mux, mux); +} + +static u8 clk_busy_mux_get_parent(struct clk_hw *hw) +{ + struct clk_busy_mux *busy = to_clk_busy_mux(hw); + + return busy->mux_ops->get_parent(&busy->mux.hw); +} + +static int clk_busy_mux_set_parent(struct clk_hw *hw, u8 index) +{ + struct clk_busy_mux *busy = to_clk_busy_mux(hw); + int ret; + + ret = busy->mux_ops->set_parent(&busy->mux.hw, index); + if (!ret) + ret = clk_busy_wait(busy->reg, busy->shift); + + return ret; +} + +static const struct clk_ops clk_busy_mux_ops = { + .get_parent = clk_busy_mux_get_parent, + .set_parent = clk_busy_mux_set_parent, +}; + +struct clk *imx_clk_busy_mux(const char *name, void __iomem *reg, u8 shift, + u8 width, void __iomem *busy_reg, u8 busy_shift, + const char * const *parent_names, int num_parents) +{ + struct clk_busy_mux *busy; + struct clk *clk; + struct clk_init_data init; + + busy = kzalloc(sizeof(*busy), GFP_KERNEL); + if (!busy) + return ERR_PTR(-ENOMEM); + + busy->reg = busy_reg; + busy->shift = busy_shift; + + busy->mux.reg = reg; + busy->mux.shift = shift; + busy->mux.mask = BIT(width) - 1; + busy->mux.lock = &imx_ccm_lock; + busy->mux_ops = &clk_mux_ops; + + init.name = name; + init.ops = &clk_busy_mux_ops; + init.flags = CLK_IS_CRITICAL; + init.parent_names = parent_names; + init.num_parents = num_parents; + + busy->mux.hw.init = &init; + + clk = clk_register(NULL, &busy->mux.hw); + if (IS_ERR(clk)) + kfree(busy); + + return clk; +} |