diff options
Diffstat (limited to 'drivers/clk/ti/composite.c')
-rw-r--r-- | drivers/clk/ti/composite.c | 276 |
1 files changed, 276 insertions, 0 deletions
diff --git a/drivers/clk/ti/composite.c b/drivers/clk/ti/composite.c new file mode 100644 index 000000000..c6478d0b9 --- /dev/null +++ b/drivers/clk/ti/composite.c @@ -0,0 +1,276 @@ +/* + * TI composite clock 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-provider.h> +#include <linux/slab.h> +#include <linux/io.h> +#include <linux/of.h> +#include <linux/of_address.h> +#include <linux/clk/ti.h> +#include <linux/list.h> + +#include "clock.h" + +#undef pr_fmt +#define pr_fmt(fmt) "%s: " fmt, __func__ + +static unsigned long ti_composite_recalc_rate(struct clk_hw *hw, + unsigned long parent_rate) +{ + return ti_clk_divider_ops.recalc_rate(hw, parent_rate); +} + +static long ti_composite_round_rate(struct clk_hw *hw, unsigned long rate, + unsigned long *prate) +{ + return -EINVAL; +} + +static int ti_composite_set_rate(struct clk_hw *hw, unsigned long rate, + unsigned long parent_rate) +{ + return -EINVAL; +} + +static const struct clk_ops ti_composite_divider_ops = { + .recalc_rate = &ti_composite_recalc_rate, + .round_rate = &ti_composite_round_rate, + .set_rate = &ti_composite_set_rate, +}; + +static const struct clk_ops ti_composite_gate_ops = { + .enable = &omap2_dflt_clk_enable, + .disable = &omap2_dflt_clk_disable, + .is_enabled = &omap2_dflt_clk_is_enabled, +}; + +struct component_clk { + int num_parents; + const char **parent_names; + struct device_node *node; + int type; + struct clk_hw *hw; + struct list_head link; +}; + +static const char * const component_clk_types[] __initconst = { + "gate", "divider", "mux" +}; + +static LIST_HEAD(component_clks); + +static struct device_node *_get_component_node(struct device_node *node, int i) +{ + int rc; + struct of_phandle_args clkspec; + + rc = of_parse_phandle_with_args(node, "clocks", "#clock-cells", i, + &clkspec); + if (rc) + return NULL; + + return clkspec.np; +} + +static struct component_clk *_lookup_component(struct device_node *node) +{ + struct component_clk *comp; + + list_for_each_entry(comp, &component_clks, link) { + if (comp->node == node) + return comp; + } + return NULL; +} + +struct clk_hw_omap_comp { + struct clk_hw hw; + struct device_node *comp_nodes[CLK_COMPONENT_TYPE_MAX]; + struct component_clk *comp_clks[CLK_COMPONENT_TYPE_MAX]; +}; + +static inline struct clk_hw *_get_hw(struct clk_hw_omap_comp *clk, int idx) +{ + if (!clk) + return NULL; + + if (!clk->comp_clks[idx]) + return NULL; + + return clk->comp_clks[idx]->hw; +} + +#define to_clk_hw_comp(_hw) container_of(_hw, struct clk_hw_omap_comp, hw) + +static void __init _register_composite(void *user, + struct device_node *node) +{ + struct clk_hw *hw = user; + struct clk *clk; + struct clk_hw_omap_comp *cclk = to_clk_hw_comp(hw); + struct component_clk *comp; + int num_parents = 0; + const char **parent_names = NULL; + int i; + int ret; + + /* Check for presence of each component clock */ + for (i = 0; i < CLK_COMPONENT_TYPE_MAX; i++) { + if (!cclk->comp_nodes[i]) + continue; + + comp = _lookup_component(cclk->comp_nodes[i]); + if (!comp) { + pr_debug("component %s not ready for %s, retry\n", + cclk->comp_nodes[i]->name, node->name); + if (!ti_clk_retry_init(node, hw, + _register_composite)) + return; + + goto cleanup; + } + if (cclk->comp_clks[comp->type] != NULL) { + pr_err("duplicate component types for %s (%s)!\n", + node->name, component_clk_types[comp->type]); + goto cleanup; + } + + cclk->comp_clks[comp->type] = comp; + + /* Mark this node as found */ + cclk->comp_nodes[i] = NULL; + } + + /* All components exists, proceed with registration */ + for (i = CLK_COMPONENT_TYPE_MAX - 1; i >= 0; i--) { + comp = cclk->comp_clks[i]; + if (!comp) + continue; + if (comp->num_parents) { + num_parents = comp->num_parents; + parent_names = comp->parent_names; + break; + } + } + + if (!num_parents) { + pr_err("%s: no parents found for %s!\n", __func__, node->name); + goto cleanup; + } + + clk = clk_register_composite(NULL, node->name, + parent_names, num_parents, + _get_hw(cclk, CLK_COMPONENT_TYPE_MUX), + &ti_clk_mux_ops, + _get_hw(cclk, CLK_COMPONENT_TYPE_DIVIDER), + &ti_composite_divider_ops, + _get_hw(cclk, CLK_COMPONENT_TYPE_GATE), + &ti_composite_gate_ops, 0); + + if (!IS_ERR(clk)) { + ret = ti_clk_add_alias(NULL, clk, node->name); + if (ret) { + clk_unregister(clk); + goto cleanup; + } + of_clk_add_provider(node, of_clk_src_simple_get, clk); + } + +cleanup: + /* Free component clock list entries */ + for (i = 0; i < CLK_COMPONENT_TYPE_MAX; i++) { + if (!cclk->comp_clks[i]) + continue; + list_del(&cclk->comp_clks[i]->link); + kfree(cclk->comp_clks[i]->parent_names); + kfree(cclk->comp_clks[i]); + } + + kfree(cclk); +} + +static void __init of_ti_composite_clk_setup(struct device_node *node) +{ + unsigned int num_clks; + int i; + struct clk_hw_omap_comp *cclk; + + /* Number of component clocks to be put inside this clock */ + num_clks = of_clk_get_parent_count(node); + + if (!num_clks) { + pr_err("composite clk %s must have component(s)\n", node->name); + return; + } + + cclk = kzalloc(sizeof(*cclk), GFP_KERNEL); + if (!cclk) + return; + + /* Get device node pointers for each component clock */ + for (i = 0; i < num_clks; i++) + cclk->comp_nodes[i] = _get_component_node(node, i); + + _register_composite(&cclk->hw, node); +} +CLK_OF_DECLARE(ti_composite_clock, "ti,composite-clock", + of_ti_composite_clk_setup); + +/** + * ti_clk_add_component - add a component clock to the pool + * @node: device node of the component clock + * @hw: hardware clock definition for the component clock + * @type: type of the component clock + * + * Adds a component clock to the list of available components, so that + * it can be registered by a composite clock. + */ +int __init ti_clk_add_component(struct device_node *node, struct clk_hw *hw, + int type) +{ + unsigned int num_parents; + const char **parent_names; + struct component_clk *clk; + + num_parents = of_clk_get_parent_count(node); + + if (!num_parents) { + pr_err("component-clock %s must have parent(s)\n", node->name); + return -EINVAL; + } + + parent_names = kzalloc((sizeof(char *) * num_parents), GFP_KERNEL); + if (!parent_names) + return -ENOMEM; + + of_clk_parent_fill(node, parent_names, num_parents); + + clk = kzalloc(sizeof(*clk), GFP_KERNEL); + if (!clk) { + kfree(parent_names); + return -ENOMEM; + } + + clk->num_parents = num_parents; + clk->parent_names = parent_names; + clk->hw = hw; + clk->node = node; + clk->type = type; + list_add(&clk->link, &component_clks); + + return 0; +} |