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Diffstat (limited to '')
-rw-r--r-- | drivers/clk/ti/clockdomain.c | 180 |
1 files changed, 180 insertions, 0 deletions
diff --git a/drivers/clk/ti/clockdomain.c b/drivers/clk/ti/clockdomain.c new file mode 100644 index 000000000..e5f447f43 --- /dev/null +++ b/drivers/clk/ti/clockdomain.c @@ -0,0 +1,180 @@ +/* + * OMAP clockdomain support + * + * Copyright (C) 2013 Texas Instruments, Inc. + * + * Tero Kristo <t-kristo@ti.com> + * + * 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. + * + * This program is distributed "as is" WITHOUT ANY WARRANTY of any + * kind, whether express or implied; without even the implied warranty + * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ + +#include <linux/clk.h> +#include <linux/clk-provider.h> +#include <linux/slab.h> +#include <linux/of.h> +#include <linux/of_address.h> +#include <linux/clk/ti.h> + +#include "clock.h" + +#undef pr_fmt +#define pr_fmt(fmt) "%s: " fmt, __func__ + +/** + * omap2_clkops_enable_clkdm - increment usecount on clkdm of @hw + * @hw: struct clk_hw * of the clock being enabled + * + * Increment the usecount of the clockdomain of the clock pointed to + * by @hw; if the usecount is 1, the clockdomain will be "enabled." + * Only needed for clocks that don't use omap2_dflt_clk_enable() as + * their enable function pointer. Passes along the return value of + * clkdm_clk_enable(), -EINVAL if @hw is not associated with a + * clockdomain, or 0 if clock framework-based clockdomain control is + * not implemented. + */ +int omap2_clkops_enable_clkdm(struct clk_hw *hw) +{ + struct clk_hw_omap *clk; + int ret = 0; + + clk = to_clk_hw_omap(hw); + + if (unlikely(!clk->clkdm)) { + pr_err("%s: %s: no clkdm set ?!\n", __func__, + clk_hw_get_name(hw)); + return -EINVAL; + } + + if (ti_clk_get_features()->flags & TI_CLK_DISABLE_CLKDM_CONTROL) { + pr_err("%s: %s: clkfw-based clockdomain control disabled ?!\n", + __func__, clk_hw_get_name(hw)); + return 0; + } + + ret = ti_clk_ll_ops->clkdm_clk_enable(clk->clkdm, hw->clk); + WARN(ret, "%s: could not enable %s's clockdomain %s: %d\n", + __func__, clk_hw_get_name(hw), clk->clkdm_name, ret); + + return ret; +} + +/** + * omap2_clkops_disable_clkdm - decrement usecount on clkdm of @hw + * @hw: struct clk_hw * of the clock being disabled + * + * Decrement the usecount of the clockdomain of the clock pointed to + * by @hw; if the usecount is 0, the clockdomain will be "disabled." + * Only needed for clocks that don't use omap2_dflt_clk_disable() as their + * disable function pointer. No return value. + */ +void omap2_clkops_disable_clkdm(struct clk_hw *hw) +{ + struct clk_hw_omap *clk; + + clk = to_clk_hw_omap(hw); + + if (unlikely(!clk->clkdm)) { + pr_err("%s: %s: no clkdm set ?!\n", __func__, + clk_hw_get_name(hw)); + return; + } + + if (ti_clk_get_features()->flags & TI_CLK_DISABLE_CLKDM_CONTROL) { + pr_err("%s: %s: clkfw-based clockdomain control disabled ?!\n", + __func__, clk_hw_get_name(hw)); + return; + } + + ti_clk_ll_ops->clkdm_clk_disable(clk->clkdm, hw->clk); +} + +/** + * omap2_init_clk_clkdm - look up a clockdomain name, store pointer in clk + * @clk: OMAP clock struct ptr to use + * + * Convert a clockdomain name stored in a struct clk 'clk' into a + * clockdomain pointer, and save it into the struct clk. Intended to be + * called during clk_register(). Returns 0 on success, -EERROR otherwise. + */ +int omap2_init_clk_clkdm(struct clk_hw *hw) +{ + struct clk_hw_omap *clk = to_clk_hw_omap(hw); + struct clockdomain *clkdm; + const char *clk_name; + + if (!clk->clkdm_name) + return 0; + + clk_name = __clk_get_name(hw->clk); + + clkdm = ti_clk_ll_ops->clkdm_lookup(clk->clkdm_name); + if (clkdm) { + pr_debug("clock: associated clk %s to clkdm %s\n", + clk_name, clk->clkdm_name); + clk->clkdm = clkdm; + } else { + pr_debug("clock: could not associate clk %s to clkdm %s\n", + clk_name, clk->clkdm_name); + } + + return 0; +} + +static void __init of_ti_clockdomain_setup(struct device_node *node) +{ + struct clk *clk; + struct clk_hw *clk_hw; + const char *clkdm_name = ti_dt_clk_name(node); + int i; + unsigned int num_clks; + + num_clks = of_clk_get_parent_count(node); + + for (i = 0; i < num_clks; i++) { + clk = of_clk_get(node, i); + if (IS_ERR(clk)) { + pr_err("%s: Failed get %pOF' clock nr %d (%ld)\n", + __func__, node, i, PTR_ERR(clk)); + continue; + } + clk_hw = __clk_get_hw(clk); + if (!omap2_clk_is_hw_omap(clk_hw)) { + pr_warn("can't setup clkdm for basic clk %s\n", + __clk_get_name(clk)); + clk_put(clk); + continue; + } + to_clk_hw_omap(clk_hw)->clkdm_name = clkdm_name; + omap2_init_clk_clkdm(clk_hw); + clk_put(clk); + } +} + +static const struct of_device_id ti_clkdm_match_table[] __initconst = { + { .compatible = "ti,clockdomain" }, + { } +}; + +/** + * ti_dt_clockdomains_setup - setup device tree clockdomains + * + * Initializes clockdomain nodes for a SoC. This parses through all the + * nodes with compatible = "ti,clockdomain", and add the clockdomain + * info for all the clocks listed under these. This function shall be + * called after rest of the DT clock init has completed and all + * clock nodes have been registered. + */ +void __init ti_dt_clockdomains_setup(void) +{ + struct device_node *np; + for_each_matching_node(np, ti_clkdm_match_table) { + of_ti_clockdomain_setup(np); + } +} |