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authorLinus Torvalds <torvalds@linux-foundation.org>2013-09-06 13:21:16 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2013-09-06 13:21:16 -0700
commit8e73e367f7dc50f1d1bc22a63e5764bb4eea9b48 (patch)
tree9bf593c1fc7612bcdd64b9ba46e41d340f9e94d3 /drivers/pwm
parentd2f3e9eb7c9e12e89f0ac5f0dbc7a9aed0ea925d (diff)
parent7323f219533e01cc075ba45a76f3e5b214adb23f (diff)
downloadop-kernel-dev-8e73e367f7dc50f1d1bc22a63e5764bb4eea9b48.zip
op-kernel-dev-8e73e367f7dc50f1d1bc22a63e5764bb4eea9b48.tar.gz
Merge tag 'cleanup-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc
Pull ARM SoC cleanups from Olof Johansson: "This branch contains code cleanups, moves and removals for 3.12. There's a large number of various cleanups, and a nice net removal of 13500 lines of code. Highlights worth mentioning are: - A series of patches from Stephen Boyd removing the ARM local timer API. - Move of Qualcomm MSM IOMMU code to drivers/iommu. - Samsung PWM driver cleanups from Tomasz Figa, removing legacy PWM driver and switching over to the drivers/pwm one. - Removal of some unusued auto-generated headers for OMAP2+ (PRM/CM). There's also a move of a header file out of include/linux/i2c/ to platform_data, where it really belongs. It touches mostly ARM platform code for include changes so we took it through our tree" * tag 'cleanup-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (83 commits) ARM: OMAP2+: Add back the define for AM33XX_RST_GLOBAL_WARM_SW_MASK gpio: (gpio-pca953x) move header to linux/platform_data/ arm: zynq: hotplug: Remove unreachable code ARM: SAMSUNG: Remove unnecessary exynos4_default_sdhci*() tegra: simplify use of devm_ioremap_resource ARM: SAMSUNG: Remove plat/regs-timer.h header ARM: SAMSUNG: Remove remaining uses of plat/regs-timer.h header ARM: SAMSUNG: Remove pwm-clock infrastructure ARM: SAMSUNG: Remove old PWM timer platform devices pwm: Remove superseded pwm-samsung-legacy driver ARM: SAMSUNG: Modify board files to use new PWM platform device ARM: SAMSUNG: Rework private data handling in dev-backlight pwm: Add new pwm-samsung driver ARM: mach-mvebu: remove redundant DT parsing and validation ARM: msm: Only compile io.c on platforms that use it iommu/msm: Move mach includes to iommu directory ARM: msm: Remove devices-iommu.c ARM: msm: Move mach/board.h contents to common.h ARM: msm: Migrate msm_timer to CLOCKSOURCE_OF_DECLARE ARM: msm: Remove TMR and TMR0 static mappings ...
Diffstat (limited to 'drivers/pwm')
-rw-r--r--drivers/pwm/pwm-samsung.c709
1 files changed, 487 insertions, 222 deletions
diff --git a/drivers/pwm/pwm-samsung.c b/drivers/pwm/pwm-samsung.c
index a0ece50..fcc8b9a 100644
--- a/drivers/pwm/pwm-samsung.c
+++ b/drivers/pwm/pwm-samsung.c
@@ -1,353 +1,618 @@
-/* drivers/pwm/pwm-samsung.c
- *
+/*
* Copyright (c) 2007 Ben Dooks
* Copyright (c) 2008 Simtec Electronics
- * Ben Dooks <ben@simtec.co.uk>, <ben-linux@fluff.org>
+ * Ben Dooks <ben@simtec.co.uk>, <ben-linux@fluff.org>
+ * Copyright (c) 2013 Tomasz Figa <tomasz.figa@gmail.com>
*
- * S3C series PWM device core
+ * PWM driver for Samsung SoCs
*
* 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; either version 2 of the License.
-*/
-
-#define pr_fmt(fmt) "pwm-samsung: " fmt
+ */
+#include <linux/bitops.h>
+#include <linux/clk.h>
#include <linux/export.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/kernel.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
#include <linux/pwm.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+#include <linux/time.h>
-#include <mach/map.h>
+/* For struct samsung_timer_variant and samsung_pwm_lock. */
+#include <clocksource/samsung_pwm.h>
-#include <plat/regs-timer.h>
+#define REG_TCFG0 0x00
+#define REG_TCFG1 0x04
+#define REG_TCON 0x08
-struct s3c_chip {
- struct platform_device *pdev;
+#define REG_TCNTB(chan) (0x0c + ((chan) * 0xc))
+#define REG_TCMPB(chan) (0x10 + ((chan) * 0xc))
- struct clk *clk_div;
- struct clk *clk;
- const char *label;
+#define TCFG0_PRESCALER_MASK 0xff
+#define TCFG0_PRESCALER1_SHIFT 8
- unsigned int period_ns;
- unsigned int duty_ns;
+#define TCFG1_MUX_MASK 0xf
+#define TCFG1_SHIFT(chan) (4 * (chan))
- unsigned char tcon_base;
- unsigned char pwm_id;
- struct pwm_chip chip;
+/*
+ * 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;
};
-#define to_s3c_chip(chip) container_of(chip, struct s3c_chip, chip)
-
-#define pwm_dbg(_pwm, msg...) dev_dbg(&(_pwm)->pdev->dev, msg)
+/**
+ * struct samsung_pwm_chip - private data of PWM chip
+ * @chip: generic PWM chip
+ * @variant: local copy of hardware variant data
+ * @inverter_mask: inverter 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)
+ */
+struct samsung_pwm_chip {
+ struct pwm_chip chip;
+ struct samsung_pwm_variant variant;
+ u8 inverter_mask;
+
+ void __iomem *base;
+ struct clk *base_clk;
+ struct clk *tclk0;
+ struct clk *tclk1;
+};
-static struct clk *clk_scaler[2];
+#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 int pwm_is_tdiv(struct s3c_chip *chip)
+static inline
+struct samsung_pwm_chip *to_samsung_pwm_chip(struct pwm_chip *chip)
{
- return clk_get_parent(chip->clk) == chip->clk_div;
+ return container_of(chip, struct samsung_pwm_chip, chip);
}
-#define pwm_tcon_start(pwm) (1 << (pwm->tcon_base + 0))
-#define pwm_tcon_invert(pwm) (1 << (pwm->tcon_base + 2))
-#define pwm_tcon_autoreload(pwm) (1 << (pwm->tcon_base + 3))
-#define pwm_tcon_manulupdate(pwm) (1 << (pwm->tcon_base + 1))
+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 int s3c_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm)
+static void pwm_samsung_set_divisor(struct samsung_pwm_chip *pwm,
+ unsigned int channel, u8 divisor)
{
- struct s3c_chip *s3c = to_s3c_chip(chip);
+ u8 shift = TCFG1_SHIFT(channel);
unsigned long flags;
- unsigned long tcon;
+ u32 reg;
+ u8 bits;
- local_irq_save(flags);
+ bits = (fls(divisor) - 1) - pwm->variant.div_base;
- tcon = __raw_readl(S3C2410_TCON);
- tcon |= pwm_tcon_start(s3c);
- __raw_writel(tcon, S3C2410_TCON);
+ spin_lock_irqsave(&samsung_pwm_lock, flags);
- local_irq_restore(flags);
+ reg = readl(pwm->base + REG_TCFG1);
+ reg &= ~(TCFG1_MUX_MASK << shift);
+ reg |= bits << shift;
+ writel(reg, pwm->base + REG_TCFG1);
- return 0;
+ spin_unlock_irqrestore(&samsung_pwm_lock, flags);
}
-static void s3c_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm)
+static int pwm_samsung_is_tdiv(struct samsung_pwm_chip *chip, unsigned int chan)
{
- struct s3c_chip *s3c = to_s3c_chip(chip);
- unsigned long flags;
- unsigned long tcon;
+ struct samsung_pwm_variant *variant = &chip->variant;
+ u32 reg;
+
+ reg = readl(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 *chip,
+ unsigned int chan)
+{
+ unsigned long rate;
+ u32 reg;
- local_irq_save(flags);
+ rate = clk_get_rate(chip->base_clk);
- tcon = __raw_readl(S3C2410_TCON);
- tcon &= ~pwm_tcon_start(s3c);
- __raw_writel(tcon, S3C2410_TCON);
+ reg = readl(chip->base + REG_TCFG0);
+ if (chan >= 2)
+ reg >>= TCFG0_PRESCALER1_SHIFT;
+ reg &= TCFG0_PRESCALER_MASK;
- local_irq_restore(flags);
+ return rate / (reg + 1);
}
-static unsigned long pwm_calc_tin(struct s3c_chip *s3c, unsigned long freq)
+static unsigned long pwm_samsung_calc_tin(struct samsung_pwm_chip *chip,
+ unsigned int chan, unsigned long freq)
{
- unsigned long tin_parent_rate;
- unsigned int div;
+ struct samsung_pwm_variant *variant = &chip->variant;
+ unsigned long rate;
+ struct clk *clk;
+ u8 div;
+
+ if (!pwm_samsung_is_tdiv(chip, chan)) {
+ clk = (chan < 2) ? chip->tclk0 : chip->tclk1;
+ if (!IS_ERR(clk)) {
+ rate = clk_get_rate(clk);
+ if (rate)
+ return rate;
+ }
+
+ dev_warn(chip->chip.dev,
+ "tclk of PWM %d is inoperational, using tdiv\n", chan);
+ }
+
+ rate = pwm_samsung_get_tin_rate(chip, chan);
+ dev_dbg(chip->chip.dev, "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.
+ */
+ for (div = variant->div_base; div < 4; ++div)
+ if ((rate >> (variant->bits + div)) < freq)
+ break;
- tin_parent_rate = clk_get_rate(clk_get_parent(s3c->clk_div));
- pwm_dbg(s3c, "tin parent at %lu\n", tin_parent_rate);
+ pwm_samsung_set_divisor(chip, chan, BIT(div));
- for (div = 2; div <= 16; div *= 2) {
- if ((tin_parent_rate / (div << 16)) < freq)
- return tin_parent_rate / 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);
+ struct samsung_pwm_channel *our_chan;
+
+ if (!(our_chip->variant.output_mask & BIT(pwm->hwpwm))) {
+ dev_warn(chip->dev,
+ "tried to request PWM channel %d without output\n",
+ pwm->hwpwm);
+ return -EINVAL;
}
- return tin_parent_rate / 16;
+ our_chan = devm_kzalloc(chip->dev, sizeof(*our_chan), GFP_KERNEL);
+ if (!our_chan)
+ return -ENOMEM;
+
+ pwm_set_chip_data(pwm, our_chan);
+
+ return 0;
}
-#define NS_IN_HZ (1000000000UL)
+static void pwm_samsung_free(struct pwm_chip *chip, struct pwm_device *pwm)
+{
+ pwm_set_chip_data(pwm, NULL);
+ devm_kfree(chip->dev, pwm_get_chip_data(pwm));
+}
-static int s3c_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
- int duty_ns, int period_ns)
+static int pwm_samsung_enable(struct pwm_chip *chip, struct pwm_device *pwm)
{
- struct s3c_chip *s3c = to_s3c_chip(chip);
- unsigned long tin_rate;
- unsigned long tin_ns;
- unsigned long period;
+ struct samsung_pwm_chip *our_chip = to_samsung_pwm_chip(chip);
+ unsigned int tcon_chan = to_tcon_channel(pwm->hwpwm);
unsigned long flags;
- unsigned long tcon;
- unsigned long tcnt;
- long tcmp;
+ u32 tcon;
- /* We currently avoid using 64bit arithmetic by using the
- * fact that anything faster than 1Hz is easily representable
- * by 32bits. */
+ 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);
+
+ 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);
+
+ spin_unlock_irqrestore(&samsung_pwm_lock, flags);
+}
- if (period_ns > NS_IN_HZ || duty_ns > NS_IN_HZ)
+static int pwm_samsung_config(struct pwm_chip *chip, struct pwm_device *pwm,
+ int duty_ns, int period_ns)
+{
+ struct samsung_pwm_chip *our_chip = to_samsung_pwm_chip(chip);
+ struct samsung_pwm_channel *chan = pwm_get_chip_data(pwm);
+ u32 tin_ns = chan->tin_ns, tcnt, tcmp;
+
+ /*
+ * We currently avoid using 64bit arithmetic by using the
+ * fact that anything faster than 1Hz is easily representable
+ * by 32bits.
+ */
+ if (period_ns > NSEC_PER_SEC)
return -ERANGE;
- if (period_ns == s3c->period_ns &&
- duty_ns == s3c->duty_ns)
+ if (period_ns == chan->period_ns && duty_ns == chan->duty_ns)
return 0;
- /* The TCMP and TCNT can be read without a lock, they're not
- * shared between the timers. */
+ tcnt = readl(our_chip->base + REG_TCNTB(pwm->hwpwm));
- tcmp = __raw_readl(S3C2410_TCMPB(s3c->pwm_id));
- tcnt = __raw_readl(S3C2410_TCNTB(s3c->pwm_id));
+ /* We need tick count for calculation, not last tick. */
+ ++tcnt;
- period = NS_IN_HZ / period_ns;
+ /* Check to see if we are changing the clock rate of the PWM. */
+ if (chan->period_ns != period_ns) {
+ unsigned long tin_rate;
+ u32 period;
- pwm_dbg(s3c, "duty_ns=%d, period_ns=%d (%lu)\n",
- duty_ns, period_ns, period);
+ period = NSEC_PER_SEC / period_ns;
- /* Check to see if we are changing the clock rate of the PWM */
+ dev_dbg(our_chip->chip.dev, "duty_ns=%d, period_ns=%d (%u)\n",
+ duty_ns, period_ns, period);
- if (s3c->period_ns != period_ns) {
- if (pwm_is_tdiv(s3c)) {
- tin_rate = pwm_calc_tin(s3c, period);
- clk_set_rate(s3c->clk_div, tin_rate);
- } else
- tin_rate = clk_get_rate(s3c->clk);
+ tin_rate = pwm_samsung_calc_tin(our_chip, pwm->hwpwm, period);
- s3c->period_ns = period_ns;
+ dev_dbg(our_chip->chip.dev, "tin_rate=%lu\n", tin_rate);
- pwm_dbg(s3c, "tin_rate=%lu\n", tin_rate);
-
- tin_ns = NS_IN_HZ / tin_rate;
+ tin_ns = NSEC_PER_SEC / tin_rate;
tcnt = period_ns / tin_ns;
- } else
- tin_ns = NS_IN_HZ / clk_get_rate(s3c->clk);
+ }
- /* Note, counters count down */
+ /* 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;
- /* the pwm hw only checks the compare register after a decrement,
- so the pin never toggles if tcmp = tcnt */
- if (tcmp == tcnt)
- tcmp--;
- pwm_dbg(s3c, "tin_ns=%lu, tcmp=%ld/%lu\n", tin_ns, tcmp, tcnt);
+ /* Decrement to get tick numbers, instead of tick counts. */
+ --tcnt;
+ /* -1UL will give 100% duty. */
+ --tcmp;
+
+ dev_dbg(our_chip->chip.dev,
+ "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));
- if (tcmp < 0)
- tcmp = 0;
+ if (test_bit(PWMF_ENABLED, &pwm->flags))
+ pwm_samsung_enable(chip, pwm);
- /* Update the PWM register block. */
+ chan->period_ns = period_ns;
+ chan->tin_ns = tin_ns;
+ chan->duty_ns = duty_ns;
- local_irq_save(flags);
+ return 0;
+}
- __raw_writel(tcmp, S3C2410_TCMPB(s3c->pwm_id));
- __raw_writel(tcnt, S3C2410_TCNTB(s3c->pwm_id));
+static void pwm_samsung_set_invert(struct samsung_pwm_chip *chip,
+ unsigned int channel, bool invert)
+{
+ unsigned int tcon_chan = to_tcon_channel(channel);
+ unsigned long flags;
+ u32 tcon;
- tcon = __raw_readl(S3C2410_TCON);
- tcon |= pwm_tcon_manulupdate(s3c);
- tcon |= pwm_tcon_autoreload(s3c);
- __raw_writel(tcon, S3C2410_TCON);
+ spin_lock_irqsave(&samsung_pwm_lock, flags);
- tcon &= ~pwm_tcon_manulupdate(s3c);
- __raw_writel(tcon, S3C2410_TCON);
+ tcon = readl(chip->base + REG_TCON);
+
+ if (invert) {
+ chip->inverter_mask |= BIT(channel);
+ tcon |= TCON_INVERT(tcon_chan);
+ } else {
+ chip->inverter_mask &= ~BIT(channel);
+ tcon &= ~TCON_INVERT(tcon_chan);
+ }
+
+ writel(tcon, 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);
- local_irq_restore(flags);
+ /* Inverted means normal in the hardware. */
+ pwm_samsung_set_invert(our_chip, pwm->hwpwm, invert);
return 0;
}
-static struct pwm_ops s3c_pwm_ops = {
- .enable = s3c_pwm_enable,
- .disable = s3c_pwm_disable,
- .config = s3c_pwm_config,
- .owner = THIS_MODULE,
+static const struct pwm_ops pwm_samsung_ops = {
+ .request = pwm_samsung_request,
+ .free = pwm_samsung_free,
+ .enable = pwm_samsung_enable,
+ .disable = pwm_samsung_disable,
+ .config = pwm_samsung_config,
+ .set_polarity = pwm_samsung_set_polarity,
+ .owner = THIS_MODULE,
};
-static int s3c_pwm_probe(struct platform_device *pdev)
+#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 },
+ {},
+};
+
+static int pwm_samsung_parse_dt(struct samsung_pwm_chip *chip)
+{
+ struct device_node *np = chip->chip.dev->of_node;
+ const struct of_device_id *match;
+ struct property *prop;
+ const __be32 *cur;
+ u32 val;
+
+ match = of_match_node(samsung_pwm_matches, np);
+ if (!match)
+ return -ENODEV;
+
+ memcpy(&chip->variant, match->data, sizeof(chip->variant));
+
+ of_property_for_each_u32(np, "samsung,pwm-outputs", prop, cur, val) {
+ if (val >= SAMSUNG_PWM_NUM) {
+ dev_err(chip->chip.dev,
+ "%s: invalid channel index in samsung,pwm-outputs property\n",
+ __func__);
+ continue;
+ }
+ chip->variant.output_mask |= BIT(val);
+ }
+
+ return 0;
+}
+#else
+static int pwm_samsung_parse_dt(struct samsung_pwm_chip *chip)
+{
+ return -ENODEV;
+}
+#endif
+
+static int pwm_samsung_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
- struct s3c_chip *s3c;
- unsigned long flags;
- unsigned long tcon;
- unsigned int id = pdev->id;
+ struct samsung_pwm_chip *chip;
+ struct resource *res;
+ unsigned int chan;
int ret;
- if (id == 4) {
- dev_err(dev, "TIMER4 is currently not supported\n");
- return -ENXIO;
- }
-
- s3c = devm_kzalloc(&pdev->dev, sizeof(*s3c), GFP_KERNEL);
- if (s3c == NULL) {
- dev_err(dev, "failed to allocate pwm_device\n");
+ chip = devm_kzalloc(&pdev->dev, sizeof(*chip), GFP_KERNEL);
+ if (chip == NULL)
return -ENOMEM;
- }
- /* calculate base of control bits in TCON */
- s3c->tcon_base = id == 0 ? 0 : (id * 4) + 4;
- s3c->pwm_id = id;
- s3c->chip.dev = &pdev->dev;
- s3c->chip.ops = &s3c_pwm_ops;
- s3c->chip.base = -1;
- s3c->chip.npwm = 1;
-
- s3c->clk = devm_clk_get(dev, "pwm-tin");
- if (IS_ERR(s3c->clk)) {
- dev_err(dev, "failed to get pwm tin clk\n");
- return PTR_ERR(s3c->clk);
+ chip->chip.dev = &pdev->dev;
+ chip->chip.ops = &pwm_samsung_ops;
+ chip->chip.base = -1;
+ chip->chip.npwm = SAMSUNG_PWM_NUM;
+ 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;
+
+ chip->chip.of_xlate = of_pwm_xlate_with_flags;
+ chip->chip.of_pwm_n_cells = 3;
+ } else {
+ if (!pdev->dev.platform_data) {
+ dev_err(&pdev->dev, "no platform data specified\n");
+ return -EINVAL;
+ }
+
+ memcpy(&chip->variant, pdev->dev.platform_data,
+ sizeof(chip->variant));
}
- s3c->clk_div = devm_clk_get(dev, "pwm-tdiv");
- if (IS_ERR(s3c->clk_div)) {
- dev_err(dev, "failed to get pwm tdiv clk\n");
- return PTR_ERR(s3c->clk_div);
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ chip->base = devm_ioremap_resource(&pdev->dev, res);
+ if (IS_ERR(chip->base))
+ return PTR_ERR(chip->base);
+
+ chip->base_clk = devm_clk_get(&pdev->dev, "timers");
+ if (IS_ERR(chip->base_clk)) {
+ dev_err(dev, "failed to get timer base clk\n");
+ return PTR_ERR(chip->base_clk);
}
- clk_enable(s3c->clk);
- clk_enable(s3c->clk_div);
+ ret = clk_prepare_enable(chip->base_clk);
+ if (ret < 0) {
+ dev_err(dev, "failed to enable base clock\n");
+ return ret;
+ }
- local_irq_save(flags);
+ for (chan = 0; chan < SAMSUNG_PWM_NUM; ++chan)
+ if (chip->variant.output_mask & BIT(chan))
+ pwm_samsung_set_invert(chip, chan, true);
- tcon = __raw_readl(S3C2410_TCON);
- tcon |= pwm_tcon_invert(s3c);
- __raw_writel(tcon, S3C2410_TCON);
+ /* Following clocks are optional. */
+ chip->tclk0 = devm_clk_get(&pdev->dev, "pwm-tclk0");
+ chip->tclk1 = devm_clk_get(&pdev->dev, "pwm-tclk1");
- local_irq_restore(flags);
+ platform_set_drvdata(pdev, chip);
- ret = pwmchip_add(&s3c->chip);
+ ret = pwmchip_add(&chip->chip);
if (ret < 0) {
- dev_err(dev, "failed to register pwm\n");
- goto err_clk_tdiv;
+ dev_err(dev, "failed to register PWM chip\n");
+ clk_disable_unprepare(chip->base_clk);
+ return ret;
}
- pwm_dbg(s3c, "config bits %02x\n",
- (__raw_readl(S3C2410_TCON) >> s3c->tcon_base) & 0x0f);
-
- dev_info(dev, "tin at %lu, tdiv at %lu, tin=%sclk, base %d\n",
- clk_get_rate(s3c->clk),
- clk_get_rate(s3c->clk_div),
- pwm_is_tdiv(s3c) ? "div" : "ext", s3c->tcon_base);
+ dev_dbg(dev, "base_clk at %lu, tclk0 at %lu, tclk1 at %lu\n",
+ clk_get_rate(chip->base_clk),
+ !IS_ERR(chip->tclk0) ? clk_get_rate(chip->tclk0) : 0,
+ !IS_ERR(chip->tclk1) ? clk_get_rate(chip->tclk1) : 0);
- platform_set_drvdata(pdev, s3c);
return 0;
-
- err_clk_tdiv:
- clk_disable(s3c->clk_div);
- clk_disable(s3c->clk);
- return ret;
}
-static int s3c_pwm_remove(struct platform_device *pdev)
+static int pwm_samsung_remove(struct platform_device *pdev)
{
- struct s3c_chip *s3c = platform_get_drvdata(pdev);
- int err;
+ struct samsung_pwm_chip *chip = platform_get_drvdata(pdev);
+ int ret;
- err = pwmchip_remove(&s3c->chip);
- if (err < 0)
- return err;
+ ret = pwmchip_remove(&chip->chip);
+ if (ret < 0)
+ return ret;
- clk_disable(s3c->clk_div);
- clk_disable(s3c->clk);
+ clk_disable_unprepare(chip->base_clk);
return 0;
}
#ifdef CONFIG_PM_SLEEP
-static int s3c_pwm_suspend(struct device *dev)
+static int pwm_samsung_suspend(struct device *dev)
{
- struct s3c_chip *s3c = dev_get_drvdata(dev);
+ struct samsung_pwm_chip *chip = dev_get_drvdata(dev);
+ unsigned int i;
- /* No one preserve these values during suspend so reset them
- * Otherwise driver leaves PWM unconfigured if same values
- * passed to pwm_config
+ /*
+ * No one preserves these values during suspend so reset them.
+ * Otherwise driver leaves PWM unconfigured if same values are
+ * passed to pwm_config() next time.
*/
- s3c->period_ns = 0;
- s3c->duty_ns = 0;
+ for (i = 0; i < SAMSUNG_PWM_NUM; ++i) {
+ struct pwm_device *pwm = &chip->chip.pwms[i];
+ struct samsung_pwm_channel *chan = pwm_get_chip_data(pwm);
+
+ if (!chan)
+ continue;
+
+ chan->period_ns = 0;
+ chan->duty_ns = 0;
+ }
return 0;
}
-static int s3c_pwm_resume(struct device *dev)
+static int pwm_samsung_resume(struct device *dev)
{
- struct s3c_chip *s3c = dev_get_drvdata(dev);
- unsigned long tcon;
+ struct samsung_pwm_chip *chip = dev_get_drvdata(dev);
+ unsigned int chan;
- /* Restore invertion */
- tcon = __raw_readl(S3C2410_TCON);
- tcon |= pwm_tcon_invert(s3c);
- __raw_writel(tcon, S3C2410_TCON);
+ /*
+ * Inverter setting must be preserved across suspend/resume
+ * as nobody really seems to configure it more than once.
+ */
+ for (chan = 0; chan < SAMSUNG_PWM_NUM; ++chan) {
+ if (chip->variant.output_mask & BIT(chan))
+ pwm_samsung_set_invert(chip, chan,
+ chip->inverter_mask & BIT(chan));
+ }
return 0;
}
#endif
-static SIMPLE_DEV_PM_OPS(s3c_pwm_pm_ops, s3c_pwm_suspend,
- s3c_pwm_resume);
+static const struct dev_pm_ops pwm_samsung_pm_ops = {
+ SET_SYSTEM_SLEEP_PM_OPS(pwm_samsung_suspend, pwm_samsung_resume)
+};
-static struct platform_driver s3c_pwm_driver = {
+static struct platform_driver pwm_samsung_driver = {
.driver = {
- .name = "s3c24xx-pwm",
+ .name = "samsung-pwm",
.owner = THIS_MODULE,
- .pm = &s3c_pwm_pm_ops,
+ .pm = &pwm_samsung_pm_ops,
+ .of_match_table = of_match_ptr(samsung_pwm_matches),
},
- .probe = s3c_pwm_probe,
- .remove = s3c_pwm_remove,
+ .probe = pwm_samsung_probe,
+ .remove = pwm_samsung_remove,
};
+module_platform_driver(pwm_samsung_driver);
-static int __init pwm_init(void)
-{
- int ret;
-
- clk_scaler[0] = clk_get(NULL, "pwm-scaler0");
- clk_scaler[1] = clk_get(NULL, "pwm-scaler1");
-
- if (IS_ERR(clk_scaler[0]) || IS_ERR(clk_scaler[1])) {
- pr_err("failed to get scaler clocks\n");
- return -EINVAL;
- }
-
- ret = platform_driver_register(&s3c_pwm_driver);
- if (ret)
- pr_err("failed to add pwm driver\n");
-
- return ret;
-}
-
-arch_initcall(pwm_init);
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Tomasz Figa <tomasz.figa@gmail.com>");
+MODULE_ALIAS("platform:samsung-pwm");
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