diff options
Diffstat (limited to 'drivers/pwm/pwm-mediatek.c')
| -rw-r--r-- | drivers/pwm/pwm-mediatek.c | 285 |
1 files changed, 176 insertions, 109 deletions
diff --git a/drivers/pwm/pwm-mediatek.c b/drivers/pwm/pwm-mediatek.c index 4291072a13a7..9d206303404a 100644 --- a/drivers/pwm/pwm-mediatek.c +++ b/drivers/pwm/pwm-mediatek.c @@ -135,50 +135,51 @@ static inline u32 pwm_mediatek_readl(struct pwm_mediatek_chip *chip, num * chip->soc->chanreg_width + offset); } -static void pwm_mediatek_enable(struct pwm_chip *chip, struct pwm_device *pwm) -{ - struct pwm_mediatek_chip *pc = to_pwm_mediatek_chip(chip); - u32 value; - - value = readl(pc->regs); - value |= BIT(pwm->hwpwm); - writel(value, pc->regs); -} - -static void pwm_mediatek_disable(struct pwm_chip *chip, struct pwm_device *pwm) -{ - struct pwm_mediatek_chip *pc = to_pwm_mediatek_chip(chip); - u32 value; - - value = readl(pc->regs); - value &= ~BIT(pwm->hwpwm); - writel(value, pc->regs); -} +struct pwm_mediatek_waveform { + u32 enable; + u32 con; + u32 width; + u32 thres; +}; -static int pwm_mediatek_config(struct pwm_chip *chip, struct pwm_device *pwm, - u64 duty_ns, u64 period_ns) +static int pwm_mediatek_round_waveform_tohw(struct pwm_chip *chip, struct pwm_device *pwm, + const struct pwm_waveform *wf, void *_wfhw) { + struct pwm_mediatek_waveform *wfhw = _wfhw; struct pwm_mediatek_chip *pc = to_pwm_mediatek_chip(chip); u32 clkdiv, enable; - u32 reg_width = PWMDWIDTH, reg_thres = PWMTHRES; u64 cnt_period, cnt_duty; unsigned long clk_rate; - int ret; + int ret = 0; - ret = pwm_mediatek_clk_enable(pc, pwm->hwpwm); - if (ret < 0) - return ret; + if (wf->period_length_ns == 0) { + *wfhw = (typeof(*wfhw)){ + .enable = 0, + }; - clk_rate = pc->clk_pwms[pwm->hwpwm].rate; + return 0; + } + + if (!pc->clk_pwms[pwm->hwpwm].rate) { + struct clk *clk = pc->clk_pwms[pwm->hwpwm].clk; + + ret = clk_prepare_enable(clk); + if (ret) + return ret; - /* Make sure we use the bus clock and not the 26MHz clock */ - if (pc->soc->pwm_ck_26m_sel_reg) - writel(0, pc->regs + pc->soc->pwm_ck_26m_sel_reg); + pc->clk_pwms[pwm->hwpwm].rate = clk_get_rate(clk); - cnt_period = mul_u64_u64_div_u64(period_ns, clk_rate, NSEC_PER_SEC); + clk_disable_unprepare(clk); + } + + clk_rate = pc->clk_pwms[pwm->hwpwm].rate; + if (clk_rate == 0 || clk_rate > 1000000000) + return -EINVAL; + + cnt_period = mul_u64_u64_div_u64(wf->period_length_ns, clk_rate, NSEC_PER_SEC); if (cnt_period == 0) { - ret = -ERANGE; - goto out; + cnt_period = 1; + ret = 1; } if (cnt_period > FIELD_MAX(PWMDWIDTH_PERIOD) + 1) { @@ -193,7 +194,7 @@ static int pwm_mediatek_config(struct pwm_chip *chip, struct pwm_device *pwm, clkdiv = 0; } - cnt_duty = mul_u64_u64_div_u64(duty_ns, clk_rate, NSEC_PER_SEC) >> clkdiv; + cnt_duty = mul_u64_u64_div_u64(wf->duty_length_ns, clk_rate, NSEC_PER_SEC) >> clkdiv; if (cnt_duty > cnt_period) cnt_duty = cnt_period; @@ -206,121 +207,187 @@ static int pwm_mediatek_config(struct pwm_chip *chip, struct pwm_device *pwm, cnt_period -= 1; - dev_dbg(&chip->dev, "pwm#%u: %lld/%lld @%lu -> CON: %x, PERIOD: %llx, DUTY: %llx\n", - pwm->hwpwm, duty_ns, period_ns, clk_rate, clkdiv, cnt_period, cnt_duty); + dev_dbg(&chip->dev, "pwm#%u: %lld/%lld @%lu -> ENABLE: %x, CON: %x, PERIOD: %llx, DUTY: %llx\n", + pwm->hwpwm, wf->duty_length_ns, wf->period_length_ns, clk_rate, + enable, clkdiv, cnt_period, cnt_duty); - if (pc->soc->pwm45_fixup && pwm->hwpwm > 2) { - /* - * PWM[4,5] has distinct offset for PWMDWIDTH and PWMTHRES - * from the other PWMs on MT7623. - */ - reg_width = PWM45DWIDTH_FIXUP; - reg_thres = PWM45THRES_FIXUP; - } + *wfhw = (typeof(*wfhw)){ + .enable = enable, + .con = clkdiv, + .width = cnt_period, + .thres = cnt_duty, + }; - pwm_mediatek_writel(pc, pwm->hwpwm, PWMCON, BIT(15) | clkdiv); - pwm_mediatek_writel(pc, pwm->hwpwm, reg_width, cnt_period); + return ret; +} - if (enable) { - pwm_mediatek_writel(pc, pwm->hwpwm, reg_thres, cnt_duty); - pwm_mediatek_enable(chip, pwm); +static int pwm_mediatek_round_waveform_fromhw(struct pwm_chip *chip, struct pwm_device *pwm, + const void *_wfhw, struct pwm_waveform *wf) +{ + const struct pwm_mediatek_waveform *wfhw = _wfhw; + struct pwm_mediatek_chip *pc = to_pwm_mediatek_chip(chip); + u32 clkdiv, cnt_period, cnt_duty; + unsigned long clk_rate; + + /* + * When _wfhw was populated, the clock was on, so .rate is + * already set appropriately. + */ + clk_rate = pc->clk_pwms[pwm->hwpwm].rate; + + if (wfhw->enable) { + clkdiv = FIELD_GET(PWMCON_CLKDIV, wfhw->con); + cnt_period = FIELD_GET(PWMDWIDTH_PERIOD, wfhw->width); + cnt_duty = FIELD_GET(PWMTHRES_DUTY, wfhw->thres); + + /* + * cnt_period is a 13 bit value, NSEC_PER_SEC is 30 bits wide + * and clkdiv is less than 8, so the multiplication doesn't + * overflow an u64. + */ + *wf = (typeof(*wf)){ + .period_length_ns = + DIV_ROUND_UP_ULL((u64)(cnt_period + 1) * NSEC_PER_SEC << clkdiv, clk_rate), + .duty_length_ns = + DIV_ROUND_UP_ULL((u64)(cnt_duty + 1) * NSEC_PER_SEC << clkdiv, clk_rate), + }; } else { - pwm_mediatek_disable(chip, pwm); + clkdiv = 0; + cnt_period = 0; + cnt_duty = 0; + + /* + * .enable = 0 is also used for too small duty_cycle values, so + * report the HW as being enabled to communicate the minimal + * period. + */ + *wf = (typeof(*wf)){ + .period_length_ns = + DIV_ROUND_UP_ULL(NSEC_PER_SEC, clk_rate), + .duty_length_ns = 0, + }; } -out: - pwm_mediatek_clk_disable(pc, pwm->hwpwm); + dev_dbg(&chip->dev, "pwm#%u: ENABLE: %x, CLKDIV: %x, PERIOD: %x, DUTY: %x @%lu -> %lld/%lld\n", + pwm->hwpwm, wfhw->enable, clkdiv, cnt_period, cnt_duty, clk_rate, + wf->duty_length_ns, wf->period_length_ns); - return ret; + return 0; } -static int pwm_mediatek_apply(struct pwm_chip *chip, struct pwm_device *pwm, - const struct pwm_state *state) +static int pwm_mediatek_read_waveform(struct pwm_chip *chip, + struct pwm_device *pwm, void *_wfhw) { + struct pwm_mediatek_waveform *wfhw = _wfhw; struct pwm_mediatek_chip *pc = to_pwm_mediatek_chip(chip); - int err; + u32 enable, clkdiv, cnt_period, cnt_duty; + u32 reg_width = PWMDWIDTH, reg_thres = PWMTHRES; + int ret; - if (state->polarity != PWM_POLARITY_NORMAL) - return -EINVAL; + ret = pwm_mediatek_clk_enable(pc, pwm->hwpwm); + if (ret < 0) + return ret; - if (!state->enabled) { - if (pwm->state.enabled) { - pwm_mediatek_disable(chip, pwm); - pwm_mediatek_clk_disable(pc, pwm->hwpwm); + enable = readl(pc->regs) & BIT(pwm->hwpwm); + + if (enable) { + if (pc->soc->pwm45_fixup && pwm->hwpwm > 2) { + /* + * PWM[4,5] has distinct offset for PWMDWIDTH and PWMTHRES + * from the other PWMs on MT7623. + */ + reg_width = PWM45DWIDTH_FIXUP; + reg_thres = PWM45THRES_FIXUP; } - return 0; - } + clkdiv = FIELD_GET(PWMCON_CLKDIV, pwm_mediatek_readl(pc, pwm->hwpwm, PWMCON)); + cnt_period = FIELD_GET(PWMDWIDTH_PERIOD, pwm_mediatek_readl(pc, pwm->hwpwm, reg_width)); + cnt_duty = FIELD_GET(PWMTHRES_DUTY, pwm_mediatek_readl(pc, pwm->hwpwm, reg_thres)); - err = pwm_mediatek_config(chip, pwm, state->duty_cycle, state->period); - if (err) - return err; + *wfhw = (typeof(*wfhw)){ + .enable = enable, + .con = BIT(15) | clkdiv, + .width = cnt_period, + .thres = cnt_duty, + }; + } else { + *wfhw = (typeof(*wfhw)){ + .enable = 0, + }; + } - if (!pwm->state.enabled) - err = pwm_mediatek_clk_enable(pc, pwm->hwpwm); + pwm_mediatek_clk_disable(pc, pwm->hwpwm); - return err; + return ret; } -static int pwm_mediatek_get_state(struct pwm_chip *chip, struct pwm_device *pwm, - struct pwm_state *state) +static int pwm_mediatek_write_waveform(struct pwm_chip *chip, + struct pwm_device *pwm, const void *_wfhw) { + const struct pwm_mediatek_waveform *wfhw = _wfhw; struct pwm_mediatek_chip *pc = to_pwm_mediatek_chip(chip); + u32 ctrl; int ret; - u32 enable; - u32 reg_width = PWMDWIDTH, reg_thres = PWMTHRES; - - if (pc->soc->pwm45_fixup && pwm->hwpwm > 2) { - /* - * PWM[4,5] has distinct offset for PWMDWIDTH and PWMTHRES - * from the other PWMs on MT7623. - */ - reg_width = PWM45DWIDTH_FIXUP; - reg_thres = PWM45THRES_FIXUP; - } ret = pwm_mediatek_clk_enable(pc, pwm->hwpwm); if (ret < 0) return ret; - enable = readl(pc->regs); - if (enable & BIT(pwm->hwpwm)) { - u32 clkdiv, cnt_period, cnt_duty; - unsigned long clk_rate; + ctrl = readl(pc->regs); - clk_rate = pc->clk_pwms[pwm->hwpwm].rate; + if (wfhw->enable) { + u32 reg_width = PWMDWIDTH, reg_thres = PWMTHRES; - state->enabled = true; - state->polarity = PWM_POLARITY_NORMAL; + if (pc->soc->pwm45_fixup && pwm->hwpwm > 2) { + /* + * PWM[4,5] has distinct offset for PWMDWIDTH and PWMTHRES + * from the other PWMs on MT7623. + */ + reg_width = PWM45DWIDTH_FIXUP; + reg_thres = PWM45THRES_FIXUP; + } - clkdiv = FIELD_GET(PWMCON_CLKDIV, - pwm_mediatek_readl(pc, pwm->hwpwm, PWMCON)); - cnt_period = FIELD_GET(PWMDWIDTH_PERIOD, - pwm_mediatek_readl(pc, pwm->hwpwm, reg_width)); - cnt_duty = FIELD_GET(PWMTHRES_DUTY, - pwm_mediatek_readl(pc, pwm->hwpwm, reg_thres)); + if (!(ctrl & BIT(pwm->hwpwm))) { + /* + * The clks are already on, just increasing the usage + * counter doesn't fail. + */ + ret = pwm_mediatek_clk_enable(pc, pwm->hwpwm); + if (unlikely(ret < 0)) + goto out; + + ctrl |= BIT(pwm->hwpwm); + writel(ctrl, pc->regs); + } - /* - * cnt_period is a 13 bit value, NSEC_PER_SEC is 30 bits wide - * and clkdiv is less than 8, so the multiplication doesn't - * overflow an u64. - */ - state->period = - DIV_ROUND_UP_ULL((u64)cnt_period * NSEC_PER_SEC << clkdiv, clk_rate); - state->duty_cycle = - DIV_ROUND_UP_ULL((u64)cnt_duty * NSEC_PER_SEC << clkdiv, clk_rate); + /* Make sure we use the bus clock and not the 26MHz clock */ + if (pc->soc->pwm_ck_26m_sel_reg) + writel(0, pc->regs + pc->soc->pwm_ck_26m_sel_reg); + + pwm_mediatek_writel(pc, pwm->hwpwm, PWMCON, BIT(15) | wfhw->con); + pwm_mediatek_writel(pc, pwm->hwpwm, reg_width, wfhw->width); + pwm_mediatek_writel(pc, pwm->hwpwm, reg_thres, wfhw->thres); } else { - state->enabled = false; + if (ctrl & BIT(pwm->hwpwm)) { + ctrl &= ~BIT(pwm->hwpwm); + writel(ctrl, pc->regs); + + pwm_mediatek_clk_disable(pc, pwm->hwpwm); + } } +out: pwm_mediatek_clk_disable(pc, pwm->hwpwm); return ret; } static const struct pwm_ops pwm_mediatek_ops = { - .apply = pwm_mediatek_apply, - .get_state = pwm_mediatek_get_state, + .sizeof_wfhw = sizeof(struct pwm_mediatek_waveform), + .round_waveform_tohw = pwm_mediatek_round_waveform_tohw, + .round_waveform_fromhw = pwm_mediatek_round_waveform_fromhw, + .read_waveform = pwm_mediatek_read_waveform, + .write_waveform = pwm_mediatek_write_waveform, }; static int pwm_mediatek_init_used_clks(struct pwm_mediatek_chip *pc) @@ -377,7 +444,7 @@ static int pwm_mediatek_probe(struct platform_device *pdev) soc = of_device_get_match_data(&pdev->dev); chip = devm_pwmchip_alloc(&pdev->dev, soc->num_pwms, - sizeof(*pc) + soc->num_pwms * sizeof(*pc->clk_pwms)); + struct_size(pc, clk_pwms, soc->num_pwms)); if (IS_ERR(chip)) return PTR_ERR(chip); pc = to_pwm_mediatek_chip(chip); |
