diff options
Diffstat (limited to 'drivers/clk/clk-gpio-gate.c')
-rw-r--r-- | drivers/clk/clk-gpio-gate.c | 322 |
1 files changed, 0 insertions, 322 deletions
diff --git a/drivers/clk/clk-gpio-gate.c b/drivers/clk/clk-gpio-gate.c deleted file mode 100644 index c0d202c24a97..000000000000 --- a/drivers/clk/clk-gpio-gate.c +++ /dev/null @@ -1,322 +0,0 @@ -/* - * Copyright (C) 2013 - 2014 Texas Instruments Incorporated - http://www.ti.com - * - * Authors: - * Jyri Sarha <jsarha@ti.com> - * Sergej Sawazki <ce3a@gmx.de> - * - * 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. - * - * Gpio controlled clock implementation - */ - -#include <linux/clk-provider.h> -#include <linux/export.h> -#include <linux/slab.h> -#include <linux/gpio.h> -#include <linux/gpio/consumer.h> -#include <linux/of_gpio.h> -#include <linux/err.h> -#include <linux/device.h> - -/** - * DOC: basic gpio gated clock which can be enabled and disabled - * with gpio output - * Traits of this clock: - * prepare - clk_(un)prepare only ensures parent is (un)prepared - * enable - clk_enable and clk_disable are functional & control gpio - * rate - inherits rate from parent. No clk_set_rate support - * parent - fixed parent. No clk_set_parent support - */ - -#define to_clk_gpio(_hw) container_of(_hw, struct clk_gpio, hw) - -static int clk_gpio_gate_enable(struct clk_hw *hw) -{ - struct clk_gpio *clk = to_clk_gpio(hw); - - gpiod_set_value(clk->gpiod, 1); - - return 0; -} - -static void clk_gpio_gate_disable(struct clk_hw *hw) -{ - struct clk_gpio *clk = to_clk_gpio(hw); - - gpiod_set_value(clk->gpiod, 0); -} - -static int clk_gpio_gate_is_enabled(struct clk_hw *hw) -{ - struct clk_gpio *clk = to_clk_gpio(hw); - - return gpiod_get_value(clk->gpiod); -} - -const struct clk_ops clk_gpio_gate_ops = { - .enable = clk_gpio_gate_enable, - .disable = clk_gpio_gate_disable, - .is_enabled = clk_gpio_gate_is_enabled, -}; -EXPORT_SYMBOL_GPL(clk_gpio_gate_ops); - -/** - * DOC: basic clock multiplexer which can be controlled with a gpio output - * Traits of this clock: - * prepare - clk_prepare only ensures that parents are prepared - * rate - rate is only affected by parent switching. No clk_set_rate support - * parent - parent is adjustable through clk_set_parent - */ - -static u8 clk_gpio_mux_get_parent(struct clk_hw *hw) -{ - struct clk_gpio *clk = to_clk_gpio(hw); - - return gpiod_get_value(clk->gpiod); -} - -static int clk_gpio_mux_set_parent(struct clk_hw *hw, u8 index) -{ - struct clk_gpio *clk = to_clk_gpio(hw); - - gpiod_set_value(clk->gpiod, index); - - return 0; -} - -const struct clk_ops clk_gpio_mux_ops = { - .get_parent = clk_gpio_mux_get_parent, - .set_parent = clk_gpio_mux_set_parent, - .determine_rate = __clk_mux_determine_rate, -}; -EXPORT_SYMBOL_GPL(clk_gpio_mux_ops); - -static struct clk *clk_register_gpio(struct device *dev, const char *name, - const char **parent_names, u8 num_parents, unsigned gpio, - bool active_low, unsigned long flags, - const struct clk_ops *clk_gpio_ops) -{ - struct clk_gpio *clk_gpio; - struct clk *clk; - struct clk_init_data init = {}; - unsigned long gpio_flags; - int err; - - if (dev) - clk_gpio = devm_kzalloc(dev, sizeof(*clk_gpio), GFP_KERNEL); - else - clk_gpio = kzalloc(sizeof(*clk_gpio), GFP_KERNEL); - - if (!clk_gpio) - return ERR_PTR(-ENOMEM); - - if (active_low) - gpio_flags = GPIOF_ACTIVE_LOW | GPIOF_OUT_INIT_HIGH; - else - gpio_flags = GPIOF_OUT_INIT_LOW; - - if (dev) - err = devm_gpio_request_one(dev, gpio, gpio_flags, name); - else - err = gpio_request_one(gpio, gpio_flags, name); - if (err) { - if (err != -EPROBE_DEFER) - pr_err("%s: %s: Error requesting clock control gpio %u\n", - __func__, name, gpio); - if (!dev) - kfree(clk_gpio); - - return ERR_PTR(err); - } - - init.name = name; - init.ops = clk_gpio_ops; - init.flags = flags | CLK_IS_BASIC; - init.parent_names = parent_names; - init.num_parents = num_parents; - - clk_gpio->gpiod = gpio_to_desc(gpio); - clk_gpio->hw.init = &init; - - if (dev) - clk = devm_clk_register(dev, &clk_gpio->hw); - else - clk = clk_register(NULL, &clk_gpio->hw); - - if (!IS_ERR(clk)) - return clk; - - if (!dev) { - gpiod_put(clk_gpio->gpiod); - kfree(clk_gpio); - } - - return clk; -} - -/** - * clk_register_gpio_gate - register a gpio clock gate with the clock framework - * @dev: device that is registering this clock - * @name: name of this clock - * @parent_name: name of this clock's parent - * @gpio: gpio number to gate this clock - * @active_low: true if gpio should be set to 0 to enable clock - * @flags: clock flags - */ -struct clk *clk_register_gpio_gate(struct device *dev, const char *name, - const char *parent_name, unsigned gpio, bool active_low, - unsigned long flags) -{ - return clk_register_gpio(dev, name, - (parent_name ? &parent_name : NULL), - (parent_name ? 1 : 0), gpio, active_low, flags, - &clk_gpio_gate_ops); -} -EXPORT_SYMBOL_GPL(clk_register_gpio_gate); - -/** - * clk_register_gpio_mux - register a gpio clock mux with the clock framework - * @dev: device that is registering this clock - * @name: name of this clock - * @parent_names: names of this clock's parents - * @num_parents: number of parents listed in @parent_names - * @gpio: gpio number to gate this clock - * @active_low: true if gpio should be set to 0 to enable clock - * @flags: clock flags - */ -struct clk *clk_register_gpio_mux(struct device *dev, const char *name, - const char **parent_names, u8 num_parents, unsigned gpio, - bool active_low, unsigned long flags) -{ - if (num_parents != 2) { - pr_err("mux-clock %s must have 2 parents\n", name); - return ERR_PTR(-EINVAL); - } - - return clk_register_gpio(dev, name, parent_names, num_parents, - gpio, active_low, flags, &clk_gpio_mux_ops); -} -EXPORT_SYMBOL_GPL(clk_register_gpio_mux); - -#ifdef CONFIG_OF -/** - * clk_register_get() has to be delayed, because -EPROBE_DEFER - * can not be handled properly at of_clk_init() call time. - */ - -struct clk_gpio_delayed_register_data { - const char *gpio_name; - struct device_node *node; - struct mutex lock; - struct clk *clk; - struct clk *(*clk_register_get)(const char *name, - const char **parent_names, u8 num_parents, - unsigned gpio, bool active_low); -}; - -static struct clk *of_clk_gpio_delayed_register_get( - struct of_phandle_args *clkspec, void *_data) -{ - struct clk_gpio_delayed_register_data *data = _data; - struct clk *clk; - const char **parent_names; - int i, num_parents; - int gpio; - enum of_gpio_flags of_flags; - - mutex_lock(&data->lock); - - if (data->clk) { - mutex_unlock(&data->lock); - return data->clk; - } - - gpio = of_get_named_gpio_flags(data->node, data->gpio_name, 0, - &of_flags); - if (gpio < 0) { - mutex_unlock(&data->lock); - if (gpio == -EPROBE_DEFER) - pr_debug("%s: %s: GPIOs not yet available, retry later\n", - data->node->name, __func__); - else - pr_err("%s: %s: Can't get '%s' DT property\n", - data->node->name, __func__, - data->gpio_name); - return ERR_PTR(gpio); - } - - num_parents = of_clk_get_parent_count(data->node); - - parent_names = kcalloc(num_parents, sizeof(char *), GFP_KERNEL); - if (!parent_names) - return ERR_PTR(-ENOMEM); - - for (i = 0; i < num_parents; i++) - parent_names[i] = of_clk_get_parent_name(data->node, i); - - clk = data->clk_register_get(data->node->name, parent_names, - num_parents, gpio, of_flags & OF_GPIO_ACTIVE_LOW); - if (IS_ERR(clk)) - goto out; - - data->clk = clk; -out: - mutex_unlock(&data->lock); - kfree(parent_names); - - return clk; -} - -static struct clk *of_clk_gpio_gate_delayed_register_get(const char *name, - const char **parent_names, u8 num_parents, - unsigned gpio, bool active_low) -{ - return clk_register_gpio_gate(NULL, name, parent_names[0], - gpio, active_low, 0); -} - -static struct clk *of_clk_gpio_mux_delayed_register_get(const char *name, - const char **parent_names, u8 num_parents, unsigned gpio, - bool active_low) -{ - return clk_register_gpio_mux(NULL, name, parent_names, num_parents, - gpio, active_low, 0); -} - -static void __init of_gpio_clk_setup(struct device_node *node, - const char *gpio_name, - struct clk *(*clk_register_get)(const char *name, - const char **parent_names, u8 num_parents, - unsigned gpio, bool active_low)) -{ - struct clk_gpio_delayed_register_data *data; - - data = kzalloc(sizeof(*data), GFP_KERNEL); - if (!data) - return; - - data->node = node; - data->gpio_name = gpio_name; - data->clk_register_get = clk_register_get; - mutex_init(&data->lock); - - of_clk_add_provider(node, of_clk_gpio_delayed_register_get, data); -} - -static void __init of_gpio_gate_clk_setup(struct device_node *node) -{ - of_gpio_clk_setup(node, "enable-gpios", - of_clk_gpio_gate_delayed_register_get); -} -CLK_OF_DECLARE(gpio_gate_clk, "gpio-gate-clock", of_gpio_gate_clk_setup); - -void __init of_gpio_mux_clk_setup(struct device_node *node) -{ - of_gpio_clk_setup(node, "select-gpios", - of_clk_gpio_mux_delayed_register_get); -} -CLK_OF_DECLARE(gpio_mux_clk, "gpio-mux-clock", of_gpio_mux_clk_setup); -#endif |