cregit-Linux how code gets into the kernel

Release 4.8 drivers/pwm/pwm-lpc32xx.c

Directory: drivers/pwm
/*
 * Copyright 2012 Alexandre Pereira da Silva <aletes.xgr@gmail.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; version 2.
 *
 */

#include <linux/clk.h>
#include <linux/err.h>
#include <linux/io.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/platform_device.h>
#include <linux/pwm.h>
#include <linux/slab.h>


struct lpc32xx_pwm_chip {
	
struct pwm_chip chip;
	
struct clk *clk;
	
void __iomem *base;
};


#define PWM_ENABLE	BIT(31)

#define PWM_PIN_LEVEL	BIT(30)


#define to_lpc32xx_pwm_chip(_chip) \
	container_of(_chip, struct lpc32xx_pwm_chip, chip)


static int lpc32xx_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm, int duty_ns, int period_ns) { struct lpc32xx_pwm_chip *lpc32xx = to_lpc32xx_pwm_chip(chip); unsigned long long c; int period_cycles, duty_cycles; u32 val; c = clk_get_rate(lpc32xx->clk); /* The highest acceptable divisor is 256, which is represented by 0 */ period_cycles = div64_u64(c * period_ns, (unsigned long long)NSEC_PER_SEC * 256); if (!period_cycles || period_cycles > 256) return -ERANGE; if (period_cycles == 256) period_cycles = 0; /* Compute 256 x #duty/period value and care for corner cases */ duty_cycles = div64_u64((unsigned long long)(period_ns - duty_ns) * 256, period_ns); if (!duty_cycles) duty_cycles = 1; if (duty_cycles > 255) duty_cycles = 255; val = readl(lpc32xx->base + (pwm->hwpwm << 2)); val &= ~0xFFFF; val |= (period_cycles << 8) | duty_cycles; writel(val, lpc32xx->base + (pwm->hwpwm << 2)); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
alexandre pereira da silvaalexandre pereira da silva9751.60%120.00%
vladimir zapolskiyvladimir zapolskiy5629.79%240.00%
axel linaxel lin3015.96%120.00%
alban bedelalban bedel52.66%120.00%
Total188100.00%5100.00%


static int lpc32xx_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm) { struct lpc32xx_pwm_chip *lpc32xx = to_lpc32xx_pwm_chip(chip); u32 val; int ret; ret = clk_prepare_enable(lpc32xx->clk); if (ret) return ret; val = readl(lpc32xx->base + (pwm->hwpwm << 2)); val |= PWM_ENABLE; writel(val, lpc32xx->base + (pwm->hwpwm << 2)); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
axel linaxel lin5662.92%133.33%
alexandre pereira da silvaalexandre pereira da silva3235.96%133.33%
vladimir zapolskiyvladimir zapolskiy11.12%133.33%
Total89100.00%3100.00%


static void lpc32xx_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm) { struct lpc32xx_pwm_chip *lpc32xx = to_lpc32xx_pwm_chip(chip); u32 val; val = readl(lpc32xx->base + (pwm->hwpwm << 2)); val &= ~PWM_ENABLE; writel(val, lpc32xx->base + (pwm->hwpwm << 2)); clk_disable_unprepare(lpc32xx->clk); }

Contributors

PersonTokensPropCommitsCommitProp
alexandre pereira da silvaalexandre pereira da silva4864.00%133.33%
axel linaxel lin2634.67%133.33%
vladimir zapolskiyvladimir zapolskiy11.33%133.33%
Total75100.00%3100.00%

static const struct pwm_ops lpc32xx_pwm_ops = { .config = lpc32xx_pwm_config, .enable = lpc32xx_pwm_enable, .disable = lpc32xx_pwm_disable, .owner = THIS_MODULE, };
static int lpc32xx_pwm_probe(struct platform_device *pdev) { struct lpc32xx_pwm_chip *lpc32xx; struct resource *res; int ret; u32 val; lpc32xx = devm_kzalloc(&pdev->dev, sizeof(*lpc32xx), GFP_KERNEL); if (!lpc32xx) return -ENOMEM; res = platform_get_resource(pdev, IORESOURCE_MEM, 0); lpc32xx->base = devm_ioremap_resource(&pdev->dev, res); if (IS_ERR(lpc32xx->base)) return PTR_ERR(lpc32xx->base); lpc32xx->clk = devm_clk_get(&pdev->dev, NULL); if (IS_ERR(lpc32xx->clk)) return PTR_ERR(lpc32xx->clk); lpc32xx->chip.dev = &pdev->dev; lpc32xx->chip.ops = &lpc32xx_pwm_ops; lpc32xx->chip.npwm = 1; lpc32xx->chip.base = -1; ret = pwmchip_add(&lpc32xx->chip); if (ret < 0) { dev_err(&pdev->dev, "failed to add PWM chip, error %d\n", ret); return ret; } /* When PWM is disable, configure the output to the default value */ val = readl(lpc32xx->base + (lpc32xx->chip.pwms[0].hwpwm << 2)); val &= ~PWM_PIN_LEVEL; writel(val, lpc32xx->base + (lpc32xx->chip.pwms[0].hwpwm << 2)); platform_set_drvdata(pdev, lpc32xx); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
alexandre pereira da silvaalexandre pereira da silva18470.50%120.00%
sylvain lemieuxsylvain lemieux5721.84%120.00%
thierry redingthierry reding103.83%120.00%
alban bedelalban bedel93.45%120.00%
vladimir zapolskiyvladimir zapolskiy10.38%120.00%
Total261100.00%5100.00%


static int lpc32xx_pwm_remove(struct platform_device *pdev) { struct lpc32xx_pwm_chip *lpc32xx = platform_get_drvdata(pdev); unsigned int i; for (i = 0; i < lpc32xx->chip.npwm; i++) pwm_disable(&lpc32xx->chip.pwms[i]); return pwmchip_remove(&lpc32xx->chip); }

Contributors

PersonTokensPropCommitsCommitProp
alexandre pereira da silvaalexandre pereira da silva3554.69%150.00%
alban bedelalban bedel2945.31%150.00%
Total64100.00%2100.00%

static const struct of_device_id lpc32xx_pwm_dt_ids[] = { { .compatible = "nxp,lpc3220-pwm", }, { /* sentinel */ } }; MODULE_DEVICE_TABLE(of, lpc32xx_pwm_dt_ids); static struct platform_driver lpc32xx_pwm_driver = { .driver = { .name = "lpc32xx-pwm", .of_match_table = lpc32xx_pwm_dt_ids, }, .probe = lpc32xx_pwm_probe, .remove = lpc32xx_pwm_remove, }; module_platform_driver(lpc32xx_pwm_driver); MODULE_ALIAS("platform:lpc32xx-pwm"); MODULE_AUTHOR("Alexandre Pereira da Silva <aletes.xgr@gmail.com>"); MODULE_DESCRIPTION("LPC32XX PWM Driver"); MODULE_LICENSE("GPL v2");

Overall Contributors

PersonTokensPropCommitsCommitProp
alexandre pereira da silvaalexandre pereira da silva56866.43%17.69%
axel linaxel lin11213.10%215.38%
sylvain lemieuxsylvain lemieux617.13%17.69%
vladimir zapolskiyvladimir zapolskiy607.02%430.77%
alban bedelalban bedel435.03%323.08%
thierry redingthierry reding111.29%215.38%
Total855100.00%13100.00%
Directory: drivers/pwm
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