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Release 4.14 arch/mips/ralink/timer.c

Directory: arch/mips/ralink
/*
 * Ralink RT2880 timer
 * Author: John Crispin
 *
 * 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.
 *
 * Copyright (C) 2013 John Crispin <john@phrozen.org>
*/

#include <linux/platform_device.h>
#include <linux/interrupt.h>
#include <linux/timer.h>
#include <linux/of_gpio.h>
#include <linux/clk.h>

#include <asm/mach-ralink/ralink_regs.h>


#define TIMER_REG_TMRSTAT		0x00

#define TIMER_REG_TMR0LOAD		0x10

#define TIMER_REG_TMR0CTL		0x18


#define TMRSTAT_TMR0INT			BIT(0)


#define TMR0CTL_ENABLE			BIT(7)

#define TMR0CTL_MODE_PERIODIC		BIT(4)

#define TMR0CTL_PRESCALER		1

#define TMR0CTL_PRESCALE_VAL		(0xf - TMR0CTL_PRESCALER)

#define TMR0CTL_PRESCALE_DIV		(65536 / BIT(TMR0CTL_PRESCALER))


struct rt_timer {
	
struct device	*dev;
	
void __iomem	*membase;
	
int		irq;
	
unsigned long	timer_freq;
	
unsigned long	timer_div;
};


static inline void rt_timer_w32(struct rt_timer *rt, u8 reg, u32 val) { __raw_writel(val, rt->membase + reg); }

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PersonTokensPropCommitsCommitProp
John Crispin29100.00%1100.00%
Total29100.00%1100.00%


static inline u32 rt_timer_r32(struct rt_timer *rt, u8 reg) { return __raw_readl(rt->membase + reg); }

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PersonTokensPropCommitsCommitProp
John Crispin25100.00%1100.00%
Total25100.00%1100.00%


static irqreturn_t rt_timer_irq(int irq, void *_rt) { struct rt_timer *rt = (struct rt_timer *) _rt; rt_timer_w32(rt, TIMER_REG_TMR0LOAD, rt->timer_freq / rt->timer_div); rt_timer_w32(rt, TIMER_REG_TMRSTAT, TMRSTAT_TMR0INT); return IRQ_HANDLED; }

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John Crispin52100.00%1100.00%
Total52100.00%1100.00%


static int rt_timer_request(struct rt_timer *rt) { int err = request_irq(rt->irq, rt_timer_irq, 0, dev_name(rt->dev), rt); if (err) { dev_err(rt->dev, "failed to request irq\n"); } else { u32 t = TMR0CTL_MODE_PERIODIC | TMR0CTL_PRESCALE_VAL; rt_timer_w32(rt, TIMER_REG_TMR0CTL, t); } return err; }

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PersonTokensPropCommitsCommitProp
John Crispin7098.59%150.00%
Michael Opdenacker11.41%150.00%
Total71100.00%2100.00%


static int rt_timer_config(struct rt_timer *rt, unsigned long divisor) { if (rt->timer_freq < divisor) rt->timer_div = rt->timer_freq; else rt->timer_div = divisor; rt_timer_w32(rt, TIMER_REG_TMR0LOAD, rt->timer_freq / rt->timer_div); return 0; }

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PersonTokensPropCommitsCommitProp
John Crispin56100.00%1100.00%
Total56100.00%1100.00%


static int rt_timer_enable(struct rt_timer *rt) { u32 t; rt_timer_w32(rt, TIMER_REG_TMR0LOAD, rt->timer_freq / rt->timer_div); t = rt_timer_r32(rt, TIMER_REG_TMR0CTL); t |= TMR0CTL_ENABLE; rt_timer_w32(rt, TIMER_REG_TMR0CTL, t); return 0; }

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PersonTokensPropCommitsCommitProp
John Crispin54100.00%1100.00%
Total54100.00%1100.00%


static int rt_timer_probe(struct platform_device *pdev) { struct resource *res = platform_get_resource(pdev, IORESOURCE_MEM, 0); struct rt_timer *rt; struct clk *clk; rt = devm_kzalloc(&pdev->dev, sizeof(*rt), GFP_KERNEL); if (!rt) { dev_err(&pdev->dev, "failed to allocate memory\n"); return -ENOMEM; } rt->irq = platform_get_irq(pdev, 0); if (!rt->irq) { dev_err(&pdev->dev, "failed to load irq\n"); return -ENOENT; } rt->membase = devm_ioremap_resource(&pdev->dev, res); if (IS_ERR(rt->membase)) return PTR_ERR(rt->membase); clk = devm_clk_get(&pdev->dev, NULL); if (IS_ERR(clk)) { dev_err(&pdev->dev, "failed get clock rate\n"); return PTR_ERR(clk); } rt->timer_freq = clk_get_rate(clk) / TMR0CTL_PRESCALE_DIV; if (!rt->timer_freq) return -EINVAL; rt->dev = &pdev->dev; platform_set_drvdata(pdev, rt); rt_timer_request(rt); rt_timer_config(rt, 2); rt_timer_enable(rt); dev_info(&pdev->dev, "maximum frequency is %luHz\n", rt->timer_freq); return 0; }

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PersonTokensPropCommitsCommitProp
John Crispin24699.19%133.33%
Wei Yongjun10.40%133.33%
Masanari Iida10.40%133.33%
Total248100.00%3100.00%

static const struct of_device_id rt_timer_match[] = { { .compatible = "ralink,rt2880-timer" }, {}, }; static struct platform_driver rt_timer_driver = { .probe = rt_timer_probe, .driver = { .name = "rt-timer", .of_match_table = rt_timer_match, .suppress_bind_attrs = true, }, }; builtin_platform_driver(rt_timer_driver);

Overall Contributors

PersonTokensPropCommitsCommitProp
John Crispin66098.36%120.00%
Paul Gortmaker81.19%120.00%
Wei Yongjun10.15%120.00%
Michael Opdenacker10.15%120.00%
Masanari Iida10.15%120.00%
Total671100.00%5100.00%
Directory: arch/mips/ralink
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