| Author | Tokens | Token Proportion | Commits | Commit Proportion |
|---|---|---|---|---|
| Tomasz Figa | 2266 | 78.33% | 2 | 9.09% |
| Uwe Kleine-König | 327 | 11.30% | 9 | 40.91% |
| Bartlomiej Zolnierkiewicz | 153 | 5.29% | 1 | 4.55% |
| Mårten Lindahl | 53 | 1.83% | 1 | 4.55% |
| Sjoerd Simons | 44 | 1.52% | 1 | 4.55% |
| Seung-Woo Kim | 21 | 0.73% | 1 | 4.55% |
| Javier Martinez Canillas | 7 | 0.24% | 1 | 4.55% |
| Dan Carpenter | 6 | 0.21% | 1 | 4.55% |
| Jeff Johnson | 5 | 0.17% | 1 | 4.55% |
| Jingoo Han | 4 | 0.14% | 1 | 4.55% |
| Sachin Kamat | 3 | 0.10% | 1 | 4.55% |
| Thomas Gleixner | 2 | 0.07% | 1 | 4.55% |
| Yangtao Li | 2 | 0.07% | 1 | 4.55% |
| Total | 2893 | 22 |
// SPDX-License-Identifier: GPL-2.0-only /* * Copyright (c) 2007 Ben Dooks * Copyright (c) 2008 Simtec Electronics * Ben Dooks <ben@simtec.co.uk>, <ben-linux@fluff.org> * Copyright (c) 2013 Tomasz Figa <tomasz.figa@gmail.com> * Copyright (c) 2017 Samsung Electronics Co., Ltd. * * PWM driver for Samsung SoCs */ #include <linux/bitops.h> #include <linux/clk.h> #include <linux/export.h> #include <linux/err.h> #include <linux/io.h> #include <linux/kernel.h> #include <linux/module.h> #include <linux/of.h> #include <linux/platform_device.h> #include <linux/pwm.h> #include <linux/slab.h> #include <linux/spinlock.h> #include <linux/time.h> /* For struct samsung_timer_variant and samsung_pwm_lock. */ #include <clocksource/samsung_pwm.h> #define REG_TCFG0 0x00 #define REG_TCFG1 0x04 #define REG_TCON 0x08 #define REG_TCNTB(chan) (0x0c + ((chan) * 0xc)) #define REG_TCMPB(chan) (0x10 + ((chan) * 0xc)) #define TCFG0_PRESCALER_MASK 0xff #define TCFG0_PRESCALER1_SHIFT 8 #define TCFG1_MUX_MASK 0xf #define TCFG1_SHIFT(chan) (4 * (chan)) /* * Each channel occupies 4 bits in TCON register, but there is a gap of 4 * bits (one channel) after channel 0, so channels have different numbering * when accessing TCON register. See to_tcon_channel() function. * * In addition, the location of autoreload bit for channel 4 (TCON channel 5) * in its set of bits is 2 as opposed to 3 for other channels. */ #define TCON_START(chan) BIT(4 * (chan) + 0) #define TCON_MANUALUPDATE(chan) BIT(4 * (chan) + 1) #define TCON_INVERT(chan) BIT(4 * (chan) + 2) #define _TCON_AUTORELOAD(chan) BIT(4 * (chan) + 3) #define _TCON_AUTORELOAD4(chan) BIT(4 * (chan) + 2) #define TCON_AUTORELOAD(chan) \ ((chan < 5) ? _TCON_AUTORELOAD(chan) : _TCON_AUTORELOAD4(chan)) /** * struct samsung_pwm_channel - private data of PWM channel * @period_ns: current period in nanoseconds programmed to the hardware * @duty_ns: current duty time in nanoseconds programmed to the hardware * @tin_ns: time of one timer tick in nanoseconds with current timer rate */ struct samsung_pwm_channel { u32 period_ns; u32 duty_ns; u32 tin_ns; }; /** * struct samsung_pwm_chip - private data of PWM chip * @variant: local copy of hardware variant data * @inverter_mask: inverter status for all channels - one bit per channel * @disabled_mask: disabled status for all channels - one bit per channel * @base: base address of mapped PWM registers * @base_clk: base clock used to drive the timers * @tclk0: external clock 0 (can be ERR_PTR if not present) * @tclk1: external clock 1 (can be ERR_PTR if not present) * @channel: per channel driver data */ struct samsung_pwm_chip { struct samsung_pwm_variant variant; u8 inverter_mask; u8 disabled_mask; void __iomem *base; struct clk *base_clk; struct clk *tclk0; struct clk *tclk1; struct samsung_pwm_channel channel[SAMSUNG_PWM_NUM]; }; #ifndef CONFIG_CLKSRC_SAMSUNG_PWM /* * PWM block is shared between pwm-samsung and samsung_pwm_timer drivers * and some registers need access synchronization. If both drivers are * compiled in, the spinlock is defined in the clocksource driver, * otherwise following definition is used. * * Currently we do not need any more complex synchronization method * because all the supported SoCs contain only one instance of the PWM * IP. Should this change, both drivers will need to be modified to * properly synchronize accesses to particular instances. */ static DEFINE_SPINLOCK(samsung_pwm_lock); #endif static inline struct samsung_pwm_chip *to_samsung_pwm_chip(struct pwm_chip *chip) { return pwmchip_get_drvdata(chip); } static inline unsigned int to_tcon_channel(unsigned int channel) { /* TCON register has a gap of 4 bits (1 channel) after channel 0 */ return (channel == 0) ? 0 : (channel + 1); } static void __pwm_samsung_manual_update(struct samsung_pwm_chip *our_chip, struct pwm_device *pwm) { unsigned int tcon_chan = to_tcon_channel(pwm->hwpwm); u32 tcon; tcon = readl(our_chip->base + REG_TCON); tcon |= TCON_MANUALUPDATE(tcon_chan); writel(tcon, our_chip->base + REG_TCON); tcon &= ~TCON_MANUALUPDATE(tcon_chan); writel(tcon, our_chip->base + REG_TCON); } static void pwm_samsung_set_divisor(struct samsung_pwm_chip *our_chip, unsigned int channel, u8 divisor) { u8 shift = TCFG1_SHIFT(channel); unsigned long flags; u32 reg; u8 bits; bits = (fls(divisor) - 1) - our_chip->variant.div_base; spin_lock_irqsave(&samsung_pwm_lock, flags); reg = readl(our_chip->base + REG_TCFG1); reg &= ~(TCFG1_MUX_MASK << shift); reg |= bits << shift; writel(reg, our_chip->base + REG_TCFG1); spin_unlock_irqrestore(&samsung_pwm_lock, flags); } static int pwm_samsung_is_tdiv(struct samsung_pwm_chip *our_chip, unsigned int chan) { struct samsung_pwm_variant *variant = &our_chip->variant; u32 reg; reg = readl(our_chip->base + REG_TCFG1); reg >>= TCFG1_SHIFT(chan); reg &= TCFG1_MUX_MASK; return (BIT(reg) & variant->tclk_mask) == 0; } static unsigned long pwm_samsung_get_tin_rate(struct samsung_pwm_chip *our_chip, unsigned int chan) { unsigned long rate; u32 reg; rate = clk_get_rate(our_chip->base_clk); reg = readl(our_chip->base + REG_TCFG0); if (chan >= 2) reg >>= TCFG0_PRESCALER1_SHIFT; reg &= TCFG0_PRESCALER_MASK; return rate / (reg + 1); } static unsigned long pwm_samsung_calc_tin(struct pwm_chip *chip, unsigned int chan, unsigned long freq) { struct samsung_pwm_chip *our_chip = to_samsung_pwm_chip(chip); struct samsung_pwm_variant *variant = &our_chip->variant; unsigned long rate; struct clk *clk; u8 div; if (!pwm_samsung_is_tdiv(our_chip, chan)) { clk = (chan < 2) ? our_chip->tclk0 : our_chip->tclk1; if (!IS_ERR(clk)) { rate = clk_get_rate(clk); if (rate) return rate; } dev_warn(pwmchip_parent(chip), "tclk of PWM %d is inoperational, using tdiv\n", chan); } rate = pwm_samsung_get_tin_rate(our_chip, chan); dev_dbg(pwmchip_parent(chip), "tin parent at %lu\n", rate); /* * Compare minimum PWM frequency that can be achieved with possible * divider settings and choose the lowest divisor that can generate * frequencies lower than requested. */ if (variant->bits < 32) { /* Only for s3c24xx */ for (div = variant->div_base; div < 4; ++div) if ((rate >> (variant->bits + div)) < freq) break; } else { /* * Other variants have enough counter bits to generate any * requested rate, so no need to check higher divisors. */ div = variant->div_base; } pwm_samsung_set_divisor(our_chip, chan, BIT(div)); return rate >> div; } static int pwm_samsung_request(struct pwm_chip *chip, struct pwm_device *pwm) { struct samsung_pwm_chip *our_chip = to_samsung_pwm_chip(chip); if (!(our_chip->variant.output_mask & BIT(pwm->hwpwm))) { dev_warn(pwmchip_parent(chip), "tried to request PWM channel %d without output\n", pwm->hwpwm); return -EINVAL; } memset(&our_chip->channel[pwm->hwpwm], 0, sizeof(our_chip->channel[pwm->hwpwm])); return 0; } static int pwm_samsung_enable(struct pwm_chip *chip, struct pwm_device *pwm) { struct samsung_pwm_chip *our_chip = to_samsung_pwm_chip(chip); unsigned int tcon_chan = to_tcon_channel(pwm->hwpwm); unsigned long flags; u32 tcon; spin_lock_irqsave(&samsung_pwm_lock, flags); tcon = readl(our_chip->base + REG_TCON); tcon &= ~TCON_START(tcon_chan); tcon |= TCON_MANUALUPDATE(tcon_chan); writel(tcon, our_chip->base + REG_TCON); tcon &= ~TCON_MANUALUPDATE(tcon_chan); tcon |= TCON_START(tcon_chan) | TCON_AUTORELOAD(tcon_chan); writel(tcon, our_chip->base + REG_TCON); our_chip->disabled_mask &= ~BIT(pwm->hwpwm); spin_unlock_irqrestore(&samsung_pwm_lock, flags); return 0; } static void pwm_samsung_disable(struct pwm_chip *chip, struct pwm_device *pwm) { struct samsung_pwm_chip *our_chip = to_samsung_pwm_chip(chip); unsigned int tcon_chan = to_tcon_channel(pwm->hwpwm); unsigned long flags; u32 tcon; spin_lock_irqsave(&samsung_pwm_lock, flags); tcon = readl(our_chip->base + REG_TCON); tcon &= ~TCON_AUTORELOAD(tcon_chan); writel(tcon, our_chip->base + REG_TCON); /* * In case the PWM is at 100% duty cycle, force a manual * update to prevent the signal from staying high. */ if (readl(our_chip->base + REG_TCMPB(pwm->hwpwm)) == (u32)-1U) __pwm_samsung_manual_update(our_chip, pwm); our_chip->disabled_mask |= BIT(pwm->hwpwm); spin_unlock_irqrestore(&samsung_pwm_lock, flags); } static void pwm_samsung_manual_update(struct samsung_pwm_chip *our_chip, struct pwm_device *pwm) { unsigned long flags; spin_lock_irqsave(&samsung_pwm_lock, flags); __pwm_samsung_manual_update(our_chip, pwm); spin_unlock_irqrestore(&samsung_pwm_lock, flags); } static int __pwm_samsung_config(struct pwm_chip *chip, struct pwm_device *pwm, int duty_ns, int period_ns, bool force_period) { struct samsung_pwm_chip *our_chip = to_samsung_pwm_chip(chip); struct samsung_pwm_channel *chan = &our_chip->channel[pwm->hwpwm]; u32 tin_ns = chan->tin_ns, tcnt, tcmp, oldtcmp; tcnt = readl(our_chip->base + REG_TCNTB(pwm->hwpwm)); oldtcmp = readl(our_chip->base + REG_TCMPB(pwm->hwpwm)); /* We need tick count for calculation, not last tick. */ ++tcnt; /* Check to see if we are changing the clock rate of the PWM. */ if (chan->period_ns != period_ns || force_period) { unsigned long tin_rate; u32 period; period = NSEC_PER_SEC / period_ns; dev_dbg(pwmchip_parent(chip), "duty_ns=%d, period_ns=%d (%u)\n", duty_ns, period_ns, period); tin_rate = pwm_samsung_calc_tin(chip, pwm->hwpwm, period); dev_dbg(pwmchip_parent(chip), "tin_rate=%lu\n", tin_rate); tin_ns = NSEC_PER_SEC / tin_rate; tcnt = period_ns / tin_ns; } /* Period is too short. */ if (tcnt <= 1) return -ERANGE; /* Note that counters count down. */ tcmp = duty_ns / tin_ns; /* 0% duty is not available */ if (!tcmp) ++tcmp; tcmp = tcnt - tcmp; /* Decrement to get tick numbers, instead of tick counts. */ --tcnt; /* -1UL will give 100% duty. */ --tcmp; dev_dbg(pwmchip_parent(chip), "tin_ns=%u, tcmp=%u/%u\n", tin_ns, tcmp, tcnt); /* Update PWM registers. */ writel(tcnt, our_chip->base + REG_TCNTB(pwm->hwpwm)); writel(tcmp, our_chip->base + REG_TCMPB(pwm->hwpwm)); /* * In case the PWM is currently at 100% duty cycle, force a manual * update to prevent the signal staying high if the PWM is disabled * shortly afer this update (before it autoreloaded the new values). */ if (oldtcmp == (u32) -1) { dev_dbg(pwmchip_parent(chip), "Forcing manual update"); pwm_samsung_manual_update(our_chip, pwm); } chan->period_ns = period_ns; chan->tin_ns = tin_ns; chan->duty_ns = duty_ns; return 0; } static int pwm_samsung_config(struct pwm_chip *chip, struct pwm_device *pwm, int duty_ns, int period_ns) { return __pwm_samsung_config(chip, pwm, duty_ns, period_ns, false); } static void pwm_samsung_set_invert(struct samsung_pwm_chip *our_chip, unsigned int channel, bool invert) { unsigned int tcon_chan = to_tcon_channel(channel); unsigned long flags; u32 tcon; spin_lock_irqsave(&samsung_pwm_lock, flags); tcon = readl(our_chip->base + REG_TCON); if (invert) { our_chip->inverter_mask |= BIT(channel); tcon |= TCON_INVERT(tcon_chan); } else { our_chip->inverter_mask &= ~BIT(channel); tcon &= ~TCON_INVERT(tcon_chan); } writel(tcon, our_chip->base + REG_TCON); spin_unlock_irqrestore(&samsung_pwm_lock, flags); } static int pwm_samsung_set_polarity(struct pwm_chip *chip, struct pwm_device *pwm, enum pwm_polarity polarity) { struct samsung_pwm_chip *our_chip = to_samsung_pwm_chip(chip); bool invert = (polarity == PWM_POLARITY_NORMAL); /* Inverted means normal in the hardware. */ pwm_samsung_set_invert(our_chip, pwm->hwpwm, invert); return 0; } static int pwm_samsung_apply(struct pwm_chip *chip, struct pwm_device *pwm, const struct pwm_state *state) { int err, enabled = pwm->state.enabled; if (state->polarity != pwm->state.polarity) { if (enabled) { pwm_samsung_disable(chip, pwm); enabled = false; } err = pwm_samsung_set_polarity(chip, pwm, state->polarity); if (err) return err; } if (!state->enabled) { if (enabled) pwm_samsung_disable(chip, pwm); return 0; } /* * We currently avoid using 64bit arithmetic by using the * fact that anything faster than 1Hz is easily representable * by 32bits. */ if (state->period > NSEC_PER_SEC) return -ERANGE; err = pwm_samsung_config(chip, pwm, state->duty_cycle, state->period); if (err) return err; if (!pwm->state.enabled) err = pwm_samsung_enable(chip, pwm); return err; } static const struct pwm_ops pwm_samsung_ops = { .request = pwm_samsung_request, .apply = pwm_samsung_apply, }; #ifdef CONFIG_OF static const struct samsung_pwm_variant s3c24xx_variant = { .bits = 16, .div_base = 1, .has_tint_cstat = false, .tclk_mask = BIT(4), }; static const struct samsung_pwm_variant s3c64xx_variant = { .bits = 32, .div_base = 0, .has_tint_cstat = true, .tclk_mask = BIT(7) | BIT(6) | BIT(5), }; static const struct samsung_pwm_variant s5p64x0_variant = { .bits = 32, .div_base = 0, .has_tint_cstat = true, .tclk_mask = 0, }; static const struct samsung_pwm_variant s5pc100_variant = { .bits = 32, .div_base = 0, .has_tint_cstat = true, .tclk_mask = BIT(5), }; static const struct of_device_id samsung_pwm_matches[] = { { .compatible = "samsung,s3c2410-pwm", .data = &s3c24xx_variant }, { .compatible = "samsung,s3c6400-pwm", .data = &s3c64xx_variant }, { .compatible = "samsung,s5p6440-pwm", .data = &s5p64x0_variant }, { .compatible = "samsung,s5pc100-pwm", .data = &s5pc100_variant }, { .compatible = "samsung,exynos4210-pwm", .data = &s5p64x0_variant }, {}, }; MODULE_DEVICE_TABLE(of, samsung_pwm_matches); static int pwm_samsung_parse_dt(struct pwm_chip *chip) { struct samsung_pwm_chip *our_chip = to_samsung_pwm_chip(chip); struct device_node *np = pwmchip_parent(chip)->of_node; const struct of_device_id *match; u32 val; match = of_match_node(samsung_pwm_matches, np); if (!match) return -ENODEV; memcpy(&our_chip->variant, match->data, sizeof(our_chip->variant)); of_property_for_each_u32(np, "samsung,pwm-outputs", val) { if (val >= SAMSUNG_PWM_NUM) { dev_err(pwmchip_parent(chip), "%s: invalid channel index in samsung,pwm-outputs property\n", __func__); continue; } our_chip->variant.output_mask |= BIT(val); } return 0; } #else static int pwm_samsung_parse_dt(struct pwm_chip *chip) { return -ENODEV; } #endif static int pwm_samsung_probe(struct platform_device *pdev) { struct device *dev = &pdev->dev; struct samsung_pwm_chip *our_chip; struct pwm_chip *chip; unsigned int chan; int ret; chip = devm_pwmchip_alloc(&pdev->dev, SAMSUNG_PWM_NUM, sizeof(*our_chip)); if (IS_ERR(chip)) return PTR_ERR(chip); our_chip = to_samsung_pwm_chip(chip); chip->ops = &pwm_samsung_ops; our_chip->inverter_mask = BIT(SAMSUNG_PWM_NUM) - 1; if (IS_ENABLED(CONFIG_OF) && pdev->dev.of_node) { ret = pwm_samsung_parse_dt(chip); if (ret) return ret; } else { if (!pdev->dev.platform_data) return dev_err_probe(&pdev->dev, -EINVAL, "no platform data specified\n"); memcpy(&our_chip->variant, pdev->dev.platform_data, sizeof(our_chip->variant)); } our_chip->base = devm_platform_ioremap_resource(pdev, 0); if (IS_ERR(our_chip->base)) return PTR_ERR(our_chip->base); our_chip->base_clk = devm_clk_get_enabled(&pdev->dev, "timers"); if (IS_ERR(our_chip->base_clk)) return dev_err_probe(dev, PTR_ERR(our_chip->base_clk), "failed to get timer base clk\n"); for (chan = 0; chan < SAMSUNG_PWM_NUM; ++chan) if (our_chip->variant.output_mask & BIT(chan)) pwm_samsung_set_invert(our_chip, chan, true); /* Following clocks are optional. */ our_chip->tclk0 = devm_clk_get(&pdev->dev, "pwm-tclk0"); our_chip->tclk1 = devm_clk_get(&pdev->dev, "pwm-tclk1"); platform_set_drvdata(pdev, chip); ret = devm_pwmchip_add(&pdev->dev, chip); if (ret < 0) return dev_err_probe(dev, ret, "failed to register PWM chip\n"); dev_dbg(dev, "base_clk at %lu, tclk0 at %lu, tclk1 at %lu\n", clk_get_rate(our_chip->base_clk), !IS_ERR(our_chip->tclk0) ? clk_get_rate(our_chip->tclk0) : 0, !IS_ERR(our_chip->tclk1) ? clk_get_rate(our_chip->tclk1) : 0); return 0; } static int pwm_samsung_resume(struct device *dev) { struct pwm_chip *chip = dev_get_drvdata(dev); struct samsung_pwm_chip *our_chip = to_samsung_pwm_chip(chip); unsigned int i; for (i = 0; i < SAMSUNG_PWM_NUM; i++) { struct pwm_device *pwm = &chip->pwms[i]; struct samsung_pwm_channel *chan = &our_chip->channel[i]; if (!test_bit(PWMF_REQUESTED, &pwm->flags)) continue; if (our_chip->variant.output_mask & BIT(i)) pwm_samsung_set_invert(our_chip, i, our_chip->inverter_mask & BIT(i)); if (chan->period_ns) { __pwm_samsung_config(chip, pwm, chan->duty_ns, chan->period_ns, true); /* needed to make PWM disable work on Odroid-XU3 */ pwm_samsung_manual_update(our_chip, pwm); } if (our_chip->disabled_mask & BIT(i)) pwm_samsung_disable(chip, pwm); else pwm_samsung_enable(chip, pwm); } return 0; } static DEFINE_SIMPLE_DEV_PM_OPS(pwm_samsung_pm_ops, NULL, pwm_samsung_resume); static struct platform_driver pwm_samsung_driver = { .driver = { .name = "samsung-pwm", .pm = pm_ptr(&pwm_samsung_pm_ops), .of_match_table = of_match_ptr(samsung_pwm_matches), }, .probe = pwm_samsung_probe, }; module_platform_driver(pwm_samsung_driver); MODULE_DESCRIPTION("Samsung Pulse Width Modulator driver"); MODULE_LICENSE("GPL"); MODULE_AUTHOR("Tomasz Figa <tomasz.figa@gmail.com>"); MODULE_ALIAS("platform:samsung-pwm");
Information contained on this website is for historical information purposes only and does not indicate or represent copyright ownership.
Created with Cregit http://github.com/cregit/cregit
Version 2.0-RC1