diff options
Diffstat (limited to 'drivers/pwm/pwm-sun4i.c')
| -rw-r--r-- | drivers/pwm/pwm-sun4i.c | 184 |
1 files changed, 84 insertions, 100 deletions
diff --git a/drivers/pwm/pwm-sun4i.c b/drivers/pwm/pwm-sun4i.c index 91ca67651abd..6c5591ca868b 100644 --- a/drivers/pwm/pwm-sun4i.c +++ b/drivers/pwm/pwm-sun4i.c @@ -17,12 +17,10 @@ #include <linux/jiffies.h> #include <linux/module.h> #include <linux/of.h> -#include <linux/of_device.h> #include <linux/platform_device.h> #include <linux/pwm.h> #include <linux/reset.h> #include <linux/slab.h> -#include <linux/spinlock.h> #include <linux/time.h> #define PWM_CTRL_REG 0x0 @@ -82,45 +80,44 @@ struct sun4i_pwm_data { }; struct sun4i_pwm_chip { - struct pwm_chip chip; struct clk *bus_clk; struct clk *clk; struct reset_control *rst; void __iomem *base; - spinlock_t ctrl_lock; const struct sun4i_pwm_data *data; - unsigned long next_period[2]; }; static inline struct sun4i_pwm_chip *to_sun4i_pwm_chip(struct pwm_chip *chip) { - return container_of(chip, struct sun4i_pwm_chip, chip); + return pwmchip_get_drvdata(chip); } -static inline u32 sun4i_pwm_readl(struct sun4i_pwm_chip *chip, +static inline u32 sun4i_pwm_readl(struct sun4i_pwm_chip *sun4ichip, unsigned long offset) { - return readl(chip->base + offset); + return readl(sun4ichip->base + offset); } -static inline void sun4i_pwm_writel(struct sun4i_pwm_chip *chip, +static inline void sun4i_pwm_writel(struct sun4i_pwm_chip *sun4ichip, u32 val, unsigned long offset) { - writel(val, chip->base + offset); + writel(val, sun4ichip->base + offset); } -static void sun4i_pwm_get_state(struct pwm_chip *chip, - struct pwm_device *pwm, - struct pwm_state *state) +static int sun4i_pwm_get_state(struct pwm_chip *chip, + struct pwm_device *pwm, + struct pwm_state *state) { - struct sun4i_pwm_chip *sun4i_pwm = to_sun4i_pwm_chip(chip); + struct sun4i_pwm_chip *sun4ichip = to_sun4i_pwm_chip(chip); u64 clk_rate, tmp; u32 val; unsigned int prescaler; - clk_rate = clk_get_rate(sun4i_pwm->clk); + clk_rate = clk_get_rate(sun4ichip->clk); + if (!clk_rate) + return -EINVAL; - val = sun4i_pwm_readl(sun4i_pwm, PWM_CTRL_REG); + val = sun4i_pwm_readl(sun4ichip, PWM_CTRL_REG); /* * PWM chapter in H6 manual has a diagram which explains that if bypass @@ -128,22 +125,22 @@ static void sun4i_pwm_get_state(struct pwm_chip *chip, * proved that also enable bit is ignored in this case. */ if ((val & BIT_CH(PWM_BYPASS, pwm->hwpwm)) && - sun4i_pwm->data->has_direct_mod_clk_output) { + sun4ichip->data->has_direct_mod_clk_output) { state->period = DIV_ROUND_UP_ULL(NSEC_PER_SEC, clk_rate); state->duty_cycle = DIV_ROUND_UP_ULL(state->period, 2); state->polarity = PWM_POLARITY_NORMAL; state->enabled = true; - return; + return 0; } if ((PWM_REG_PRESCAL(val, pwm->hwpwm) == PWM_PRESCAL_MASK) && - sun4i_pwm->data->has_prescaler_bypass) + sun4ichip->data->has_prescaler_bypass) prescaler = 1; else prescaler = prescaler_table[PWM_REG_PRESCAL(val, pwm->hwpwm)]; if (prescaler == 0) - return; + return -EINVAL; if (val & BIT_CH(PWM_ACT_STATE, pwm->hwpwm)) state->polarity = PWM_POLARITY_NORMAL; @@ -156,16 +153,18 @@ static void sun4i_pwm_get_state(struct pwm_chip *chip, else state->enabled = false; - val = sun4i_pwm_readl(sun4i_pwm, PWM_CH_PRD(pwm->hwpwm)); + val = sun4i_pwm_readl(sun4ichip, PWM_CH_PRD(pwm->hwpwm)); tmp = (u64)prescaler * NSEC_PER_SEC * PWM_REG_DTY(val); state->duty_cycle = DIV_ROUND_CLOSEST_ULL(tmp, clk_rate); tmp = (u64)prescaler * NSEC_PER_SEC * PWM_REG_PRD(val); state->period = DIV_ROUND_CLOSEST_ULL(tmp, clk_rate); + + return 0; } -static int sun4i_pwm_calculate(struct sun4i_pwm_chip *sun4i_pwm, +static int sun4i_pwm_calculate(struct sun4i_pwm_chip *sun4ichip, const struct pwm_state *state, u32 *dty, u32 *prd, unsigned int *prsclr, bool *bypass) @@ -173,9 +172,9 @@ static int sun4i_pwm_calculate(struct sun4i_pwm_chip *sun4i_pwm, u64 clk_rate, div = 0; unsigned int prescaler = 0; - clk_rate = clk_get_rate(sun4i_pwm->clk); + clk_rate = clk_get_rate(sun4ichip->clk); - *bypass = sun4i_pwm->data->has_direct_mod_clk_output && + *bypass = sun4ichip->data->has_direct_mod_clk_output && state->enabled && (state->period * clk_rate >= NSEC_PER_SEC) && (state->period * clk_rate < 2 * NSEC_PER_SEC) && @@ -185,7 +184,7 @@ static int sun4i_pwm_calculate(struct sun4i_pwm_chip *sun4i_pwm, if (*bypass) return 0; - if (sun4i_pwm->data->has_prescaler_bypass) { + if (sun4ichip->data->has_prescaler_bypass) { /* First, test without any prescaler when available */ prescaler = PWM_PRESCAL_MASK; /* @@ -231,42 +230,39 @@ static int sun4i_pwm_calculate(struct sun4i_pwm_chip *sun4i_pwm, static int sun4i_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm, const struct pwm_state *state) { - struct sun4i_pwm_chip *sun4i_pwm = to_sun4i_pwm_chip(chip); + struct sun4i_pwm_chip *sun4ichip = to_sun4i_pwm_chip(chip); struct pwm_state cstate; u32 ctrl, duty = 0, period = 0, val; int ret; unsigned int delay_us, prescaler = 0; - unsigned long now; bool bypass; pwm_get_state(pwm, &cstate); if (!cstate.enabled) { - ret = clk_prepare_enable(sun4i_pwm->clk); + ret = clk_prepare_enable(sun4ichip->clk); if (ret) { - dev_err(chip->dev, "failed to enable PWM clock\n"); + dev_err(pwmchip_parent(chip), "failed to enable PWM clock\n"); return ret; } } - ret = sun4i_pwm_calculate(sun4i_pwm, state, &duty, &period, &prescaler, + ret = sun4i_pwm_calculate(sun4ichip, state, &duty, &period, &prescaler, &bypass); if (ret) { - dev_err(chip->dev, "period exceeds the maximum value\n"); + dev_err(pwmchip_parent(chip), "period exceeds the maximum value\n"); if (!cstate.enabled) - clk_disable_unprepare(sun4i_pwm->clk); + clk_disable_unprepare(sun4ichip->clk); return ret; } - spin_lock(&sun4i_pwm->ctrl_lock); - ctrl = sun4i_pwm_readl(sun4i_pwm, PWM_CTRL_REG); + ctrl = sun4i_pwm_readl(sun4ichip, PWM_CTRL_REG); - if (sun4i_pwm->data->has_direct_mod_clk_output) { + if (sun4ichip->data->has_direct_mod_clk_output) { if (bypass) { ctrl |= BIT_CH(PWM_BYPASS, pwm->hwpwm); /* We can skip other parameter */ - sun4i_pwm_writel(sun4i_pwm, ctrl, PWM_CTRL_REG); - spin_unlock(&sun4i_pwm->ctrl_lock); + sun4i_pwm_writel(sun4ichip, ctrl, PWM_CTRL_REG); return 0; } @@ -276,16 +272,14 @@ static int sun4i_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm, if (PWM_REG_PRESCAL(ctrl, pwm->hwpwm) != prescaler) { /* Prescaler changed, the clock has to be gated */ ctrl &= ~BIT_CH(PWM_CLK_GATING, pwm->hwpwm); - sun4i_pwm_writel(sun4i_pwm, ctrl, PWM_CTRL_REG); + sun4i_pwm_writel(sun4ichip, ctrl, PWM_CTRL_REG); ctrl &= ~BIT_CH(PWM_PRESCAL_MASK, pwm->hwpwm); ctrl |= BIT_CH(prescaler, pwm->hwpwm); } val = (duty & PWM_DTY_MASK) | PWM_PRD(period); - sun4i_pwm_writel(sun4i_pwm, val, PWM_CH_PRD(pwm->hwpwm)); - sun4i_pwm->next_period[pwm->hwpwm] = jiffies + - nsecs_to_jiffies(cstate.period + 1000); + sun4i_pwm_writel(sun4ichip, val, PWM_CH_PRD(pwm->hwpwm)); if (state->polarity != PWM_POLARITY_NORMAL) ctrl &= ~BIT_CH(PWM_ACT_STATE, pwm->hwpwm); @@ -297,32 +291,24 @@ static int sun4i_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm, if (state->enabled) ctrl |= BIT_CH(PWM_EN, pwm->hwpwm); - sun4i_pwm_writel(sun4i_pwm, ctrl, PWM_CTRL_REG); - - spin_unlock(&sun4i_pwm->ctrl_lock); + sun4i_pwm_writel(sun4ichip, ctrl, PWM_CTRL_REG); if (state->enabled) return 0; /* We need a full period to elapse before disabling the channel. */ - now = jiffies; - if (time_before(now, sun4i_pwm->next_period[pwm->hwpwm])) { - delay_us = jiffies_to_usecs(sun4i_pwm->next_period[pwm->hwpwm] - - now); - if ((delay_us / 500) > MAX_UDELAY_MS) - msleep(delay_us / 1000 + 1); - else - usleep_range(delay_us, delay_us * 2); - } + delay_us = DIV_ROUND_UP_ULL(cstate.period, NSEC_PER_USEC); + if ((delay_us / 500) > MAX_UDELAY_MS) + msleep(delay_us / 1000 + 1); + else + usleep_range(delay_us, delay_us * 2); - spin_lock(&sun4i_pwm->ctrl_lock); - ctrl = sun4i_pwm_readl(sun4i_pwm, PWM_CTRL_REG); + ctrl = sun4i_pwm_readl(sun4ichip, PWM_CTRL_REG); ctrl &= ~BIT_CH(PWM_CLK_GATING, pwm->hwpwm); ctrl &= ~BIT_CH(PWM_EN, pwm->hwpwm); - sun4i_pwm_writel(sun4i_pwm, ctrl, PWM_CTRL_REG); - spin_unlock(&sun4i_pwm->ctrl_lock); + sun4i_pwm_writel(sun4ichip, ctrl, PWM_CTRL_REG); - clk_disable_unprepare(sun4i_pwm->clk); + clk_disable_unprepare(sun4ichip->clk); return 0; } @@ -330,7 +316,6 @@ static int sun4i_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm, static const struct pwm_ops sun4i_pwm_ops = { .apply = sun4i_pwm_apply, .get_state = sun4i_pwm_get_state, - .owner = THIS_MODULE, }; static const struct sun4i_pwm_data sun4i_pwm_dual_nobypass = { @@ -390,20 +375,24 @@ MODULE_DEVICE_TABLE(of, sun4i_pwm_dt_ids); static int sun4i_pwm_probe(struct platform_device *pdev) { - struct sun4i_pwm_chip *pwm; + struct pwm_chip *chip; + const struct sun4i_pwm_data *data; + struct sun4i_pwm_chip *sun4ichip; int ret; - pwm = devm_kzalloc(&pdev->dev, sizeof(*pwm), GFP_KERNEL); - if (!pwm) - return -ENOMEM; - - pwm->data = of_device_get_match_data(&pdev->dev); - if (!pwm->data) + data = of_device_get_match_data(&pdev->dev); + if (!data) return -ENODEV; - pwm->base = devm_platform_ioremap_resource(pdev, 0); - if (IS_ERR(pwm->base)) - return PTR_ERR(pwm->base); + chip = devm_pwmchip_alloc(&pdev->dev, data->npwm, sizeof(*sun4ichip)); + if (IS_ERR(chip)) + return PTR_ERR(chip); + sun4ichip = to_sun4i_pwm_chip(chip); + + sun4ichip->data = data; + sun4ichip->base = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(sun4ichip->base)) + return PTR_ERR(sun4ichip->base); /* * All hardware variants need a source clock that is divided and @@ -416,30 +405,30 @@ static int sun4i_pwm_probe(struct platform_device *pdev) * unnamed one of the PWM device) and if this is not found we fall * back to the first clock of the PWM. */ - pwm->clk = devm_clk_get_optional(&pdev->dev, "mod"); - if (IS_ERR(pwm->clk)) - return dev_err_probe(&pdev->dev, PTR_ERR(pwm->clk), + sun4ichip->clk = devm_clk_get_optional(&pdev->dev, "mod"); + if (IS_ERR(sun4ichip->clk)) + return dev_err_probe(&pdev->dev, PTR_ERR(sun4ichip->clk), "get mod clock failed\n"); - if (!pwm->clk) { - pwm->clk = devm_clk_get(&pdev->dev, NULL); - if (IS_ERR(pwm->clk)) - return dev_err_probe(&pdev->dev, PTR_ERR(pwm->clk), + if (!sun4ichip->clk) { + sun4ichip->clk = devm_clk_get(&pdev->dev, NULL); + if (IS_ERR(sun4ichip->clk)) + return dev_err_probe(&pdev->dev, PTR_ERR(sun4ichip->clk), "get unnamed clock failed\n"); } - pwm->bus_clk = devm_clk_get_optional(&pdev->dev, "bus"); - if (IS_ERR(pwm->bus_clk)) - return dev_err_probe(&pdev->dev, PTR_ERR(pwm->bus_clk), + sun4ichip->bus_clk = devm_clk_get_optional(&pdev->dev, "bus"); + if (IS_ERR(sun4ichip->bus_clk)) + return dev_err_probe(&pdev->dev, PTR_ERR(sun4ichip->bus_clk), "get bus clock failed\n"); - pwm->rst = devm_reset_control_get_optional_shared(&pdev->dev, NULL); - if (IS_ERR(pwm->rst)) - return dev_err_probe(&pdev->dev, PTR_ERR(pwm->rst), + sun4ichip->rst = devm_reset_control_get_optional_shared(&pdev->dev, NULL); + if (IS_ERR(sun4ichip->rst)) + return dev_err_probe(&pdev->dev, PTR_ERR(sun4ichip->rst), "get reset failed\n"); /* Deassert reset */ - ret = reset_control_deassert(pwm->rst); + ret = reset_control_deassert(sun4ichip->rst); if (ret) { dev_err(&pdev->dev, "cannot deassert reset control: %pe\n", ERR_PTR(ret)); @@ -450,47 +439,42 @@ static int sun4i_pwm_probe(struct platform_device *pdev) * We're keeping the bus clock on for the sake of simplicity. * Actually it only needs to be on for hardware register accesses. */ - ret = clk_prepare_enable(pwm->bus_clk); + ret = clk_prepare_enable(sun4ichip->bus_clk); if (ret) { dev_err(&pdev->dev, "cannot prepare and enable bus_clk %pe\n", ERR_PTR(ret)); goto err_bus; } - pwm->chip.dev = &pdev->dev; - pwm->chip.ops = &sun4i_pwm_ops; - pwm->chip.npwm = pwm->data->npwm; + chip->ops = &sun4i_pwm_ops; - spin_lock_init(&pwm->ctrl_lock); - - ret = pwmchip_add(&pwm->chip); + ret = pwmchip_add(chip); if (ret < 0) { dev_err(&pdev->dev, "failed to add PWM chip: %d\n", ret); goto err_pwm_add; } - platform_set_drvdata(pdev, pwm); + platform_set_drvdata(pdev, chip); return 0; err_pwm_add: - clk_disable_unprepare(pwm->bus_clk); + clk_disable_unprepare(sun4ichip->bus_clk); err_bus: - reset_control_assert(pwm->rst); + reset_control_assert(sun4ichip->rst); return ret; } -static int sun4i_pwm_remove(struct platform_device *pdev) +static void sun4i_pwm_remove(struct platform_device *pdev) { - struct sun4i_pwm_chip *pwm = platform_get_drvdata(pdev); - - pwmchip_remove(&pwm->chip); + struct pwm_chip *chip = platform_get_drvdata(pdev); + struct sun4i_pwm_chip *sun4ichip = to_sun4i_pwm_chip(chip); - clk_disable_unprepare(pwm->bus_clk); - reset_control_assert(pwm->rst); + pwmchip_remove(chip); - return 0; + clk_disable_unprepare(sun4ichip->bus_clk); + reset_control_assert(sun4ichip->rst); } static struct platform_driver sun4i_pwm_driver = { |
