diff options
author | Alexandre Belloni <alexandre.belloni@bootlin.com> | 2020-10-30 19:36:56 +0100 |
---|---|---|
committer | Thierry Reding <thierry.reding@gmail.com> | 2020-12-17 14:18:55 +0100 |
commit | 061f8572a31c0da6621aacfc70ed16e1a6d1d33b (patch) | |
tree | 4f67d61aa95c3b73c68dc51a0d92b2133354f541 /drivers/pwm | |
parent | cd6720ba022bae39e0b37ec12a3fc810643a779c (diff) | |
download | linux-061f8572a31c0da6621aacfc70ed16e1a6d1d33b.tar.bz2 |
pwm: atmel-tcb: Switch to new binding
The PWM is now a subnode of the used TCB. This is cleaner and it mainly
allows to stop wasting TCB channels when only 2 or 4 PWMs are used.
This also removes the atmel_tclib dependency
Cc: Thierry Reding <thierry.reding@gmail.com>
Cc: linux-pwm@vger.kernel.org
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Diffstat (limited to 'drivers/pwm')
-rw-r--r-- | drivers/pwm/Kconfig | 3 | ||||
-rw-r--r-- | drivers/pwm/pwm-atmel-tcb.c | 241 |
2 files changed, 137 insertions, 107 deletions
diff --git a/drivers/pwm/Kconfig b/drivers/pwm/Kconfig index 63be5362fd3a..ce02d7fe9513 100644 --- a/drivers/pwm/Kconfig +++ b/drivers/pwm/Kconfig @@ -75,7 +75,8 @@ config PWM_ATMEL_HLCDC_PWM config PWM_ATMEL_TCB tristate "Atmel TC Block PWM support" - depends on ATMEL_TCLIB && OF + depends on OF + select REGMAP_MMIO help Generic PWM framework driver for Atmel Timer Counter Block. diff --git a/drivers/pwm/pwm-atmel-tcb.c b/drivers/pwm/pwm-atmel-tcb.c index 85c53701958c..82edb44fbbd8 100644 --- a/drivers/pwm/pwm-atmel-tcb.c +++ b/drivers/pwm/pwm-atmel-tcb.c @@ -16,13 +16,16 @@ #include <linux/err.h> #include <linux/ioport.h> #include <linux/io.h> +#include <linux/mfd/syscon.h> #include <linux/platform_device.h> #include <linux/pwm.h> #include <linux/of_device.h> +#include <linux/of_irq.h> +#include <linux/regmap.h> #include <linux/slab.h> #include <soc/at91/atmel_tcb.h> -#define NPWM 6 +#define NPWM 2 #define ATMEL_TC_ACMR_MASK (ATMEL_TC_ACPA | ATMEL_TC_ACPC | \ ATMEL_TC_AEEVT | ATMEL_TC_ASWTRG) @@ -48,11 +51,17 @@ struct atmel_tcb_channel { struct atmel_tcb_pwm_chip { struct pwm_chip chip; spinlock_t lock; - struct atmel_tc *tc; + u8 channel; + u8 width; + struct regmap *regmap; + struct clk *clk; + struct clk *slow_clk; struct atmel_tcb_pwm_device *pwms[NPWM]; - struct atmel_tcb_channel bkup[NPWM / 2]; + struct atmel_tcb_channel bkup; }; +const u8 atmel_tcb_divisors[] = { 2, 8, 32, 128, 0, }; + static inline struct atmel_tcb_pwm_chip *to_tcb_chip(struct pwm_chip *chip) { return container_of(chip, struct atmel_tcb_pwm_chip, chip); @@ -74,10 +83,6 @@ static int atmel_tcb_pwm_request(struct pwm_chip *chip, { struct atmel_tcb_pwm_chip *tcbpwmc = to_tcb_chip(chip); struct atmel_tcb_pwm_device *tcbpwm; - struct atmel_tc *tc = tcbpwmc->tc; - void __iomem *regs = tc->regs; - unsigned group = pwm->hwpwm / 2; - unsigned index = pwm->hwpwm % 2; unsigned cmr; int ret; @@ -85,7 +90,7 @@ static int atmel_tcb_pwm_request(struct pwm_chip *chip, if (!tcbpwm) return -ENOMEM; - ret = clk_prepare_enable(tc->clk[group]); + ret = clk_prepare_enable(tcbpwmc->clk); if (ret) { devm_kfree(chip->dev, tcbpwm); return ret; @@ -98,28 +103,31 @@ static int atmel_tcb_pwm_request(struct pwm_chip *chip, tcbpwm->div = 0; spin_lock(&tcbpwmc->lock); - cmr = __raw_readl(regs + ATMEL_TC_REG(group, CMR)); + regmap_read(tcbpwmc->regmap, ATMEL_TC_REG(tcbpwmc->channel, CMR), &cmr); /* * Get init config from Timer Counter registers if * Timer Counter is already configured as a PWM generator. */ if (cmr & ATMEL_TC_WAVE) { - if (index == 0) - tcbpwm->duty = - __raw_readl(regs + ATMEL_TC_REG(group, RA)); + if (pwm->hwpwm == 0) + regmap_read(tcbpwmc->regmap, + ATMEL_TC_REG(tcbpwmc->channel, RA), + &tcbpwm->duty); else - tcbpwm->duty = - __raw_readl(regs + ATMEL_TC_REG(group, RB)); + regmap_read(tcbpwmc->regmap, + ATMEL_TC_REG(tcbpwmc->channel, RB), + &tcbpwm->duty); tcbpwm->div = cmr & ATMEL_TC_TCCLKS; - tcbpwm->period = __raw_readl(regs + ATMEL_TC_REG(group, RC)); + regmap_read(tcbpwmc->regmap, ATMEL_TC_REG(tcbpwmc->channel, RC), + &tcbpwm->period); cmr &= (ATMEL_TC_TCCLKS | ATMEL_TC_ACMR_MASK | ATMEL_TC_BCMR_MASK); } else cmr = 0; cmr |= ATMEL_TC_WAVE | ATMEL_TC_WAVESEL_UP_AUTO | ATMEL_TC_EEVT_XC0; - __raw_writel(cmr, regs + ATMEL_TC_REG(group, CMR)); + regmap_write(tcbpwmc->regmap, ATMEL_TC_REG(tcbpwmc->channel, CMR), cmr); spin_unlock(&tcbpwmc->lock); tcbpwmc->pwms[pwm->hwpwm] = tcbpwm; @@ -131,9 +139,8 @@ static void atmel_tcb_pwm_free(struct pwm_chip *chip, struct pwm_device *pwm) { struct atmel_tcb_pwm_chip *tcbpwmc = to_tcb_chip(chip); struct atmel_tcb_pwm_device *tcbpwm = pwm_get_chip_data(pwm); - struct atmel_tc *tc = tcbpwmc->tc; - clk_disable_unprepare(tc->clk[pwm->hwpwm / 2]); + clk_disable_unprepare(tcbpwmc->clk); tcbpwmc->pwms[pwm->hwpwm] = NULL; devm_kfree(chip->dev, tcbpwm); } @@ -142,10 +149,6 @@ static void atmel_tcb_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm) { struct atmel_tcb_pwm_chip *tcbpwmc = to_tcb_chip(chip); struct atmel_tcb_pwm_device *tcbpwm = pwm_get_chip_data(pwm); - struct atmel_tc *tc = tcbpwmc->tc; - void __iomem *regs = tc->regs; - unsigned group = pwm->hwpwm / 2; - unsigned index = pwm->hwpwm % 2; unsigned cmr; enum pwm_polarity polarity = tcbpwm->polarity; @@ -161,10 +164,10 @@ static void atmel_tcb_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm) polarity = !polarity; spin_lock(&tcbpwmc->lock); - cmr = __raw_readl(regs + ATMEL_TC_REG(group, CMR)); + regmap_read(tcbpwmc->regmap, ATMEL_TC_REG(tcbpwmc->channel, CMR), &cmr); /* flush old setting and set the new one */ - if (index == 0) { + if (pwm->hwpwm == 0) { cmr &= ~ATMEL_TC_ACMR_MASK; if (polarity == PWM_POLARITY_INVERSED) cmr |= ATMEL_TC_ASWTRG_CLEAR; @@ -178,20 +181,22 @@ static void atmel_tcb_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm) cmr |= ATMEL_TC_BSWTRG_SET; } - __raw_writel(cmr, regs + ATMEL_TC_REG(group, CMR)); + regmap_write(tcbpwmc->regmap, ATMEL_TC_REG(tcbpwmc->channel, CMR), cmr); /* * Use software trigger to apply the new setting. * If both PWM devices in this group are disabled we stop the clock. */ if (!(cmr & (ATMEL_TC_ACPC | ATMEL_TC_BCPC))) { - __raw_writel(ATMEL_TC_SWTRG | ATMEL_TC_CLKDIS, - regs + ATMEL_TC_REG(group, CCR)); - tcbpwmc->bkup[group].enabled = 1; + regmap_write(tcbpwmc->regmap, + ATMEL_TC_REG(tcbpwmc->channel, CCR), + ATMEL_TC_SWTRG | ATMEL_TC_CLKDIS); + tcbpwmc->bkup.enabled = 1; } else { - __raw_writel(ATMEL_TC_SWTRG, regs + - ATMEL_TC_REG(group, CCR)); - tcbpwmc->bkup[group].enabled = 0; + regmap_write(tcbpwmc->regmap, + ATMEL_TC_REG(tcbpwmc->channel, CCR), + ATMEL_TC_SWTRG); + tcbpwmc->bkup.enabled = 0; } spin_unlock(&tcbpwmc->lock); @@ -201,10 +206,6 @@ static int atmel_tcb_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm) { struct atmel_tcb_pwm_chip *tcbpwmc = to_tcb_chip(chip); struct atmel_tcb_pwm_device *tcbpwm = pwm_get_chip_data(pwm); - struct atmel_tc *tc = tcbpwmc->tc; - void __iomem *regs = tc->regs; - unsigned group = pwm->hwpwm / 2; - unsigned index = pwm->hwpwm % 2; u32 cmr; enum pwm_polarity polarity = tcbpwm->polarity; @@ -220,12 +221,12 @@ static int atmel_tcb_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm) polarity = !polarity; spin_lock(&tcbpwmc->lock); - cmr = __raw_readl(regs + ATMEL_TC_REG(group, CMR)); + regmap_read(tcbpwmc->regmap, ATMEL_TC_REG(tcbpwmc->channel, CMR), &cmr); /* flush old setting and set the new one */ cmr &= ~ATMEL_TC_TCCLKS; - if (index == 0) { + if (pwm->hwpwm == 0) { cmr &= ~ATMEL_TC_ACMR_MASK; /* Set CMR flags according to given polarity */ @@ -248,7 +249,7 @@ static int atmel_tcb_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm) * this config till next config call. */ if (tcbpwm->duty != tcbpwm->period && tcbpwm->duty > 0) { - if (index == 0) { + if (pwm->hwpwm == 0) { if (polarity == PWM_POLARITY_INVERSED) cmr |= ATMEL_TC_ACPA_SET | ATMEL_TC_ACPC_CLEAR; else @@ -263,19 +264,24 @@ static int atmel_tcb_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm) cmr |= (tcbpwm->div & ATMEL_TC_TCCLKS); - __raw_writel(cmr, regs + ATMEL_TC_REG(group, CMR)); + regmap_write(tcbpwmc->regmap, ATMEL_TC_REG(tcbpwmc->channel, CMR), cmr); - if (index == 0) - __raw_writel(tcbpwm->duty, regs + ATMEL_TC_REG(group, RA)); + if (pwm->hwpwm == 0) + regmap_write(tcbpwmc->regmap, + ATMEL_TC_REG(tcbpwmc->channel, RA), + tcbpwm->duty); else - __raw_writel(tcbpwm->duty, regs + ATMEL_TC_REG(group, RB)); + regmap_write(tcbpwmc->regmap, + ATMEL_TC_REG(tcbpwmc->channel, RB), + tcbpwm->duty); - __raw_writel(tcbpwm->period, regs + ATMEL_TC_REG(group, RC)); + regmap_write(tcbpwmc->regmap, ATMEL_TC_REG(tcbpwmc->channel, RC), + tcbpwm->period); /* Use software trigger to apply the new setting */ - __raw_writel(ATMEL_TC_CLKEN | ATMEL_TC_SWTRG, - regs + ATMEL_TC_REG(group, CCR)); - tcbpwmc->bkup[group].enabled = 1; + regmap_write(tcbpwmc->regmap, ATMEL_TC_REG(tcbpwmc->channel, CCR), + ATMEL_TC_SWTRG | ATMEL_TC_CLKEN); + tcbpwmc->bkup.enabled = 1; spin_unlock(&tcbpwmc->lock); return 0; } @@ -285,15 +291,12 @@ static int atmel_tcb_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm, { struct atmel_tcb_pwm_chip *tcbpwmc = to_tcb_chip(chip); struct atmel_tcb_pwm_device *tcbpwm = pwm_get_chip_data(pwm); - unsigned group = pwm->hwpwm / 2; - unsigned index = pwm->hwpwm % 2; struct atmel_tcb_pwm_device *atcbpwm = NULL; - struct atmel_tc *tc = tcbpwmc->tc; int i; int slowclk = 0; unsigned period; unsigned duty; - unsigned rate = clk_get_rate(tc->clk[group]); + unsigned rate = clk_get_rate(tcbpwmc->clk); unsigned long long min; unsigned long long max; @@ -301,13 +304,13 @@ static int atmel_tcb_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm, * Find best clk divisor: * the smallest divisor which can fulfill the period_ns requirements. */ - for (i = 0; i < 5; ++i) { - if (atmel_tc_divisors[i] == 0) { + for (i = 0; i < ARRAY_SIZE(atmel_tcb_divisors); ++i) { + if (atmel_tcb_divisors[i] == 0) { slowclk = i; continue; } - min = div_u64((u64)NSEC_PER_SEC * atmel_tc_divisors[i], rate); - max = min << tc->tcb_config->counter_width; + min = div_u64((u64)NSEC_PER_SEC * atmel_tcb_divisors[i], rate); + max = min << tcbpwmc->width; if (max >= period_ns) break; } @@ -316,11 +319,11 @@ static int atmel_tcb_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm, * If none of the divisor are small enough to represent period_ns * take slow clock (32KHz). */ - if (i == 5) { + if (i == ARRAY_SIZE(atmel_tcb_divisors)) { i = slowclk; - rate = clk_get_rate(tc->slow_clk); + rate = clk_get_rate(tcbpwmc->slow_clk); min = div_u64(NSEC_PER_SEC, rate); - max = min << tc->tcb_config->counter_width; + max = min << tcbpwmc->width; /* If period is too big return ERANGE error */ if (max < period_ns) @@ -330,17 +333,13 @@ static int atmel_tcb_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm, duty = div_u64(duty_ns, min); period = div_u64(period_ns, min); - if (index == 0) - atcbpwm = tcbpwmc->pwms[pwm->hwpwm + 1]; + if (pwm->hwpwm == 0) + atcbpwm = tcbpwmc->pwms[1]; else - atcbpwm = tcbpwmc->pwms[pwm->hwpwm - 1]; + atcbpwm = tcbpwmc->pwms[0]; /* - * PWM devices provided by TCB driver are grouped by 2: - * - group 0: PWM 0 & 1 - * - group 1: PWM 2 & 3 - * - group 2: PWM 4 & 5 - * + * PWM devices provided by the TCB driver are grouped by 2. * PWM devices in a given group must be configured with the * same period_ns. * @@ -376,32 +375,63 @@ static const struct pwm_ops atmel_tcb_pwm_ops = { .owner = THIS_MODULE, }; +static struct atmel_tcb_config tcb_rm9200_config = { + .counter_width = 16, +}; + +static struct atmel_tcb_config tcb_sam9x5_config = { + .counter_width = 32, +}; + +static const struct of_device_id atmel_tcb_of_match[] = { + { .compatible = "atmel,at91rm9200-tcb", .data = &tcb_rm9200_config, }, + { .compatible = "atmel,at91sam9x5-tcb", .data = &tcb_sam9x5_config, }, + { /* sentinel */ } +}; + static int atmel_tcb_pwm_probe(struct platform_device *pdev) { + const struct of_device_id *match; struct atmel_tcb_pwm_chip *tcbpwm; + const struct atmel_tcb_config *config; struct device_node *np = pdev->dev.of_node; - struct atmel_tc *tc; + struct regmap *regmap; + struct clk *clk; + struct clk *slow_clk; + char clk_name[] = "t0_clk"; int err; - int tcblock; + int channel; - err = of_property_read_u32(np, "tc-block", &tcblock); + err = of_property_read_u32(np, "reg", &channel); if (err < 0) { dev_err(&pdev->dev, - "failed to get Timer Counter Block number from device tree (error: %d)\n", + "failed to get Timer Counter Block channel from device tree (error: %d)\n", err); return err; } - tc = atmel_tc_alloc(tcblock); - if (tc == NULL) { - dev_err(&pdev->dev, "failed to allocate Timer Counter Block\n"); - return -ENOMEM; - } + regmap = syscon_node_to_regmap(np->parent); + if (IS_ERR(regmap)) + return PTR_ERR(regmap); + + slow_clk = of_clk_get_by_name(np->parent, "slow_clk"); + if (IS_ERR(slow_clk)) + return PTR_ERR(slow_clk); + + clk_name[1] += channel; + clk = of_clk_get_by_name(np->parent, clk_name); + if (IS_ERR(clk)) + clk = of_clk_get_by_name(np->parent, "t0_clk"); + if (IS_ERR(clk)) + return PTR_ERR(clk); + + match = of_match_node(atmel_tcb_of_match, np->parent); + config = match->data; tcbpwm = devm_kzalloc(&pdev->dev, sizeof(*tcbpwm), GFP_KERNEL); if (tcbpwm == NULL) { err = -ENOMEM; - goto err_free_tc; + goto err_slow_clk; } tcbpwm->chip.dev = &pdev->dev; @@ -410,11 +440,15 @@ static int atmel_tcb_pwm_probe(struct platform_device *pdev) tcbpwm->chip.of_pwm_n_cells = 3; tcbpwm->chip.base = -1; tcbpwm->chip.npwm = NPWM; - tcbpwm->tc = tc; + tcbpwm->channel = channel; + tcbpwm->regmap = regmap; + tcbpwm->clk = clk; + tcbpwm->slow_clk = slow_clk; + tcbpwm->width = config->counter_width; - err = clk_prepare_enable(tc->slow_clk); + err = clk_prepare_enable(slow_clk); if (err) - goto err_free_tc; + goto err_slow_clk; spin_lock_init(&tcbpwm->lock); @@ -427,10 +461,10 @@ static int atmel_tcb_pwm_probe(struct platform_device *pdev) return 0; err_disable_clk: - clk_disable_unprepare(tcbpwm->tc->slow_clk); + clk_disable_unprepare(tcbpwm->slow_clk); -err_free_tc: - atmel_tc_free(tc); +err_slow_clk: + clk_put(slow_clk); return err; } @@ -440,14 +474,14 @@ static int atmel_tcb_pwm_remove(struct platform_device *pdev) struct atmel_tcb_pwm_chip *tcbpwm = platform_get_drvdata(pdev); int err; - clk_disable_unprepare(tcbpwm->tc->slow_clk); + clk_disable_unprepare(tcbpwm->slow_clk); + clk_put(tcbpwm->slow_clk); + clk_put(tcbpwm->clk); err = pwmchip_remove(&tcbpwm->chip); if (err < 0) return err; - atmel_tc_free(tcbpwm->tc); - return 0; } @@ -461,38 +495,33 @@ MODULE_DEVICE_TABLE(of, atmel_tcb_pwm_dt_ids); static int atmel_tcb_pwm_suspend(struct device *dev) { struct atmel_tcb_pwm_chip *tcbpwm = dev_get_drvdata(dev); - void __iomem *base = tcbpwm->tc->regs; - int i; + struct atmel_tcb_channel *chan = &tcbpwm->bkup; + unsigned int channel = tcbpwm->channel; - for (i = 0; i < (NPWM / 2); i++) { - struct atmel_tcb_channel *chan = &tcbpwm->bkup[i]; + regmap_read(tcbpwm->regmap, ATMEL_TC_REG(channel, CMR), &chan->cmr); + regmap_read(tcbpwm->regmap, ATMEL_TC_REG(channel, RA), &chan->ra); + regmap_read(tcbpwm->regmap, ATMEL_TC_REG(channel, RB), &chan->rb); + regmap_read(tcbpwm->regmap, ATMEL_TC_REG(channel, RC), &chan->rc); - chan->cmr = readl(base + ATMEL_TC_REG(i, CMR)); - chan->ra = readl(base + ATMEL_TC_REG(i, RA)); - chan->rb = readl(base + ATMEL_TC_REG(i, RB)); - chan->rc = readl(base + ATMEL_TC_REG(i, RC)); - } return 0; } static int atmel_tcb_pwm_resume(struct device *dev) { struct atmel_tcb_pwm_chip *tcbpwm = dev_get_drvdata(dev); - void __iomem *base = tcbpwm->tc->regs; - int i; + struct atmel_tcb_channel *chan = &tcbpwm->bkup; + unsigned int channel = tcbpwm->channel; - for (i = 0; i < (NPWM / 2); i++) { - struct atmel_tcb_channel *chan = &tcbpwm->bkup[i]; + regmap_write(tcbpwm->regmap, ATMEL_TC_REG(channel, CMR), chan->cmr); + regmap_write(tcbpwm->regmap, ATMEL_TC_REG(channel, RA), chan->ra); + regmap_write(tcbpwm->regmap, ATMEL_TC_REG(channel, RB), chan->rb); + regmap_write(tcbpwm->regmap, ATMEL_TC_REG(channel, RC), chan->rc); + + if (chan->enabled) + regmap_write(tcbpwm->regmap, + ATMEL_TC_CLKEN | ATMEL_TC_SWTRG, + ATMEL_TC_REG(channel, CCR)); - writel(chan->cmr, base + ATMEL_TC_REG(i, CMR)); - writel(chan->ra, base + ATMEL_TC_REG(i, RA)); - writel(chan->rb, base + ATMEL_TC_REG(i, RB)); - writel(chan->rc, base + ATMEL_TC_REG(i, RC)); - if (chan->enabled) { - writel(ATMEL_TC_CLKEN | ATMEL_TC_SWTRG, - base + ATMEL_TC_REG(i, CCR)); - } - } return 0; } #endif |