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Linux kernel mirror (for testing) git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
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123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224// SPDX-License-Identifier: GPL-2.0-only/* * Copyright (c) 2017, Linaro Ltd. All rights reserved. * * Author: Daniel Lezcano <daniel.lezcano@linaro.org> */#include <linux/clk.h>#include <linux/interrupt.h>#include <linux/of.h>#include <linux/of_address.h>#include <linux/of_irq.h>#include <linux/slab.h>
#include "timer-of.h"
/** * timer_of_irq_exit - Release the interrupt * @of_irq: an of_timer_irq structure pointer * * Free the irq resource */static void timer_of_irq_exit(struct of_timer_irq *of_irq){ struct timer_of *to = container_of(of_irq, struct timer_of, of_irq);
struct clock_event_device *clkevt = &to->clkevt;
free_irq(of_irq->irq, clkevt);}
/** * timer_of_irq_init - Request the interrupt * @np: a device tree node pointer * @of_irq: an of_timer_irq structure pointer * * Get the interrupt number from the DT from its definition and * request it. The interrupt is gotten by falling back the following way: * * - Get interrupt number by name * - Get interrupt number by index * * Returns 0 on success, < 0 otherwise */static int timer_of_irq_init(struct device_node *np, struct of_timer_irq *of_irq){ int ret; struct timer_of *to = container_of(of_irq, struct timer_of, of_irq); struct clock_event_device *clkevt = &to->clkevt;
if (of_irq->name) { of_irq->irq = ret = of_irq_get_byname(np, of_irq->name); if (ret < 0) { pr_err("Failed to get interrupt %s for %pOF\n", of_irq->name, np); return ret; } } else { of_irq->irq = irq_of_parse_and_map(np, of_irq->index); } if (!of_irq->irq) { pr_err("Failed to map interrupt for %pOF\n", np); return -EINVAL; }
ret = request_irq(of_irq->irq, of_irq->handler, of_irq->flags ? of_irq->flags : IRQF_TIMER, np->full_name, clkevt); if (ret) { pr_err("Failed to request irq %d for %pOF\n", of_irq->irq, np); return ret; }
clkevt->irq = of_irq->irq;
return 0;}
/** * timer_of_clk_exit - Release the clock resources * @of_clk: a of_timer_clk structure pointer * * Disables and releases the refcount on the clk */static void timer_of_clk_exit(struct of_timer_clk *of_clk){ of_clk->rate = 0; clk_disable_unprepare(of_clk->clk); clk_put(of_clk->clk);}
/** * timer_of_clk_init - Initialize the clock resources * @np: a device tree node pointer * @of_clk: a of_timer_clk structure pointer * * Get the clock by name or by index, enable it and get the rate * * Returns 0 on success, < 0 otherwise */static int timer_of_clk_init(struct device_node *np, struct of_timer_clk *of_clk){ int ret;
of_clk->clk = of_clk->name ? of_clk_get_by_name(np, of_clk->name) : of_clk_get(np, of_clk->index); if (IS_ERR(of_clk->clk)) { ret = PTR_ERR(of_clk->clk); if (ret != -EPROBE_DEFER) pr_err("Failed to get clock for %pOF\n", np); goto out; }
ret = clk_prepare_enable(of_clk->clk); if (ret) { pr_err("Failed for enable clock for %pOF\n", np); goto out_clk_put; }
of_clk->rate = clk_get_rate(of_clk->clk); if (!of_clk->rate) { ret = -EINVAL; pr_err("Failed to get clock rate for %pOF\n", np); goto out_clk_disable; }
of_clk->period = DIV_ROUND_UP(of_clk->rate, HZ);out: return ret;
out_clk_disable: clk_disable_unprepare(of_clk->clk);out_clk_put: clk_put(of_clk->clk);
goto out;}
static void timer_of_base_exit(struct of_timer_base *of_base){ iounmap(of_base->base);}
static int timer_of_base_init(struct device_node *np, struct of_timer_base *of_base){ of_base->base = of_base->name ? of_io_request_and_map(np, of_base->index, of_base->name) : of_iomap(np, of_base->index); if (IS_ERR_OR_NULL(of_base->base)) { pr_err("Failed to iomap (%s:%s)\n", np->name, of_base->name); return of_base->base ? PTR_ERR(of_base->base) : -ENOMEM; }
return 0;}
int timer_of_init(struct device_node *np, struct timer_of *to){ int ret = -EINVAL; int flags = 0;
if (to->flags & TIMER_OF_BASE) { ret = timer_of_base_init(np, &to->of_base); if (ret) goto out_fail; flags |= TIMER_OF_BASE; }
if (to->flags & TIMER_OF_CLOCK) { ret = timer_of_clk_init(np, &to->of_clk); if (ret) goto out_fail; flags |= TIMER_OF_CLOCK; }
if (to->flags & TIMER_OF_IRQ) { ret = timer_of_irq_init(np, &to->of_irq); if (ret) goto out_fail; flags |= TIMER_OF_IRQ; }
if (!to->clkevt.name) to->clkevt.name = np->full_name;
to->np = np;
return ret;
out_fail: if (flags & TIMER_OF_IRQ) timer_of_irq_exit(&to->of_irq);
if (flags & TIMER_OF_CLOCK) timer_of_clk_exit(&to->of_clk);
if (flags & TIMER_OF_BASE) timer_of_base_exit(&to->of_base); return ret;}EXPORT_SYMBOL_GPL(timer_of_init);
/** * timer_of_cleanup - release timer_of resources * @to: timer_of structure * * Release the resources that has been used in timer_of_init(). * This function should be called in init error cases */void timer_of_cleanup(struct timer_of *to){ if (to->flags & TIMER_OF_IRQ) timer_of_irq_exit(&to->of_irq);
if (to->flags & TIMER_OF_CLOCK) timer_of_clk_exit(&to->of_clk);
if (to->flags & TIMER_OF_BASE) timer_of_base_exit(&to->of_base);}EXPORT_SYMBOL_GPL(timer_of_cleanup);