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Release 4.11 drivers/pwm/pwm-pxa.c

Directory: drivers/pwm
/*
 * drivers/pwm/pwm-pxa.c
 *
 * simple driver for PWM (Pulse Width Modulator) controller
 *
 * 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.
 *
 * 2008-02-13   initial version
 *              eric miao <eric.miao@marvell.com>
 */

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

#include <asm/div64.h>


#define HAS_SECONDARY_PWM	0x10


static const struct platform_device_id pwm_id_table[] = {
	/*   PWM    has_secondary_pwm? */
	{ "pxa25x-pwm", 0 },
	{ "pxa27x-pwm", HAS_SECONDARY_PWM },
	{ "pxa168-pwm", 0 },
	{ "pxa910-pwm", 0 },
	{ },
};
MODULE_DEVICE_TABLE(platform, pwm_id_table);

/* PWM registers and bits definitions */

#define PWMCR		(0x00)

#define PWMDCR		(0x04)

#define PWMPCR		(0x08)


#define PWMCR_SD	(1 << 6)

#define PWMDCR_FD	(1 << 10)


struct pxa_pwm_chip {
	
struct pwm_chip	chip;
	
struct device	*dev;

	
struct clk	*clk;
	
void __iomem	*mmio_base;
};


static inline struct pxa_pwm_chip *to_pxa_pwm_chip(struct pwm_chip *chip) { return container_of(chip, struct pxa_pwm_chip, chip); }

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Thierry Reding25100.00%1100.00%
Total25100.00%1100.00%

/* * period_ns = 10^9 * (PRESCALE + 1) * (PV + 1) / PWM_CLK_RATE * duty_ns = 10^9 * (PRESCALE + 1) * DC / PWM_CLK_RATE */
static int pxa_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm, int duty_ns, int period_ns) { struct pxa_pwm_chip *pc = to_pxa_pwm_chip(chip); unsigned long long c; unsigned long period_cycles, prescale, pv, dc; unsigned long offset; int rc; offset = pwm->hwpwm ? 0x10 : 0; c = clk_get_rate(pc->clk); c = c * period_ns; do_div(c, 1000000000); period_cycles = c; if (period_cycles < 1) period_cycles = 1; prescale = (period_cycles - 1) / 1024; pv = period_cycles / (prescale + 1) - 1; if (prescale > 63) return -EINVAL; if (duty_ns == period_ns) dc = PWMDCR_FD; else dc = (pv + 1) * duty_ns / period_ns; /* NOTE: the clock to PWM has to be enabled first * before writing to the registers */ rc = clk_prepare_enable(pc->clk); if (rc < 0) return rc; writel(prescale, pc->mmio_base + offset + PWMCR); writel(dc, pc->mmio_base + offset + PWMDCR); writel(pv, pc->mmio_base + offset + PWMPCR); clk_disable_unprepare(pc->clk); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Eric Miao16071.75%133.33%
Thierry Reding6227.80%133.33%
Roel Kluin10.45%133.33%
Total223100.00%3100.00%


static int pxa_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm) { struct pxa_pwm_chip *pc = to_pxa_pwm_chip(chip); return clk_prepare_enable(pc->clk); }

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PersonTokensPropCommitsCommitProp
Thierry Reding1955.88%133.33%
Eric Miao1441.18%133.33%
Axel Lin12.94%133.33%
Total34100.00%3100.00%


static void pxa_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm) { struct pxa_pwm_chip *pc = to_pxa_pwm_chip(chip); clk_disable_unprepare(pc->clk); }

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PersonTokensPropCommitsCommitProp
Thierry Reding1957.58%150.00%
Eric Miao1442.42%150.00%
Total33100.00%2100.00%

static const struct pwm_ops pxa_pwm_ops = { .config = pxa_pwm_config, .enable = pxa_pwm_enable, .disable = pxa_pwm_disable, .owner = THIS_MODULE, }; #ifdef CONFIG_OF /* * Device tree users must create one device instance for each PWM channel. * Hence we dispense with the HAS_SECONDARY_PWM and "tell" the original driver * code that this is a single channel pxa25x-pwm. Currently all devices are * supported identically. */ static const struct of_device_id pwm_of_match[] = { { .compatible = "marvell,pxa250-pwm", .data = &pwm_id_table[0]}, { .compatible = "marvell,pxa270-pwm", .data = &pwm_id_table[0]}, { .compatible = "marvell,pxa168-pwm", .data = &pwm_id_table[0]}, { .compatible = "marvell,pxa910-pwm", .data = &pwm_id_table[0]}, { } }; MODULE_DEVICE_TABLE(of, pwm_of_match); #else #define pwm_of_match NULL #endif
static const struct platform_device_id *pxa_pwm_get_id_dt(struct device *dev) { const struct of_device_id *id = of_match_device(pwm_of_match, dev); return id ? id->data : NULL; }

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PersonTokensPropCommitsCommitProp
Mike Dunn36100.00%1100.00%
Total36100.00%1100.00%


static struct pwm_device * pxa_pwm_of_xlate(struct pwm_chip *pc, const struct of_phandle_args *args) { struct pwm_device *pwm; pwm = pwm_request_from_chip(pc, 0, NULL); if (IS_ERR(pwm)) return pwm; pwm->args.period = args->args[0]; return pwm; }

Contributors

PersonTokensPropCommitsCommitProp
Mike Dunn5691.80%150.00%
Boris Brezillon58.20%150.00%
Total61100.00%2100.00%


static int pwm_probe(struct platform_device *pdev) { const struct platform_device_id *id = platform_get_device_id(pdev); struct pxa_pwm_chip *pwm; struct resource *r; int ret = 0; if (IS_ENABLED(CONFIG_OF) && id == NULL) id = pxa_pwm_get_id_dt(&pdev->dev); if (id == NULL) return -EINVAL; pwm = devm_kzalloc(&pdev->dev, sizeof(*pwm), GFP_KERNEL); if (pwm == NULL) return -ENOMEM; pwm->clk = devm_clk_get(&pdev->dev, NULL); if (IS_ERR(pwm->clk)) return PTR_ERR(pwm->clk); pwm->chip.dev = &pdev->dev; pwm->chip.ops = &pxa_pwm_ops; pwm->chip.base = -1; pwm->chip.npwm = (id->driver_data & HAS_SECONDARY_PWM) ? 2 : 1; if (IS_ENABLED(CONFIG_OF)) { pwm->chip.of_xlate = pxa_pwm_of_xlate; pwm->chip.of_pwm_n_cells = 1; } r = platform_get_resource(pdev, IORESOURCE_MEM, 0); pwm->mmio_base = devm_ioremap_resource(&pdev->dev, r); if (IS_ERR(pwm->mmio_base)) return PTR_ERR(pwm->mmio_base); ret = pwmchip_add(&pwm->chip); if (ret < 0) { dev_err(&pdev->dev, "pwmchip_add() failed: %d\n", ret); return ret; } platform_set_drvdata(pdev, pwm); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Eric Miao14350.35%222.22%
Thierry Reding6823.94%222.22%
Mike Dunn5619.72%111.11%
Axel Lin144.93%111.11%
H Hartley Sweeten10.35%111.11%
Russell King10.35%111.11%
Uwe Kleine-König10.35%111.11%
Total284100.00%9100.00%


static int pwm_remove(struct platform_device *pdev) { struct pxa_pwm_chip *chip; chip = platform_get_drvdata(pdev); if (chip == NULL) return -ENODEV; return pwmchip_remove(&chip->chip); }

Contributors

PersonTokensPropCommitsCommitProp
Eric Miao3480.95%250.00%
Thierry Reding819.05%250.00%
Total42100.00%4100.00%

static struct platform_driver pwm_driver = { .driver = { .name = "pxa25x-pwm", .of_match_table = pwm_of_match, }, .probe = pwm_probe, .remove = pwm_remove, .id_table = pwm_id_table, }; module_platform_driver(pwm_driver); MODULE_LICENSE("GPL v2");

Overall Contributors

PersonTokensPropCommitsCommitProp
Eric Miao51950.34%312.50%
Mike Dunn24123.38%28.33%
Thierry Reding23322.60%625.00%
Axel Lin171.65%312.50%
Guennadi Liakhovetski50.48%14.17%
Boris Brezillon50.48%14.17%
Tejun Heo30.29%14.17%
Ben Dooks20.19%14.17%
Bhumika Goyal10.10%14.17%
Jingoo Han10.10%14.17%
Russell King10.10%14.17%
Uwe Kleine-König10.10%14.17%
Roel Kluin10.10%14.17%
H Hartley Sweeten10.10%14.17%
Total1031100.00%24100.00%
Directory: drivers/pwm
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