diff options
Diffstat (limited to 'drivers/pwm/pwm-meson.c')
-rw-r--r-- | drivers/pwm/pwm-meson.c | 123 |
1 files changed, 95 insertions, 28 deletions
diff --git a/drivers/pwm/pwm-meson.c b/drivers/pwm/pwm-meson.c index 98e6c1533312..8c6bf3d49753 100644 --- a/drivers/pwm/pwm-meson.c +++ b/drivers/pwm/pwm-meson.c @@ -6,7 +6,7 @@ * PWM output is achieved by calculating a clock that permits calculating * two periods (low and high). The counter then has to be set to switch after * N cycles for the first half period. - * The hardware has no "polarity" setting. This driver reverses the period + * Partly the hardware has no "polarity" setting. This driver reverses the period * cycles (the low length is inverted with the high length) for * PWM_POLARITY_INVERSED. This means that .get_state cannot read the polarity * from the hardware. @@ -56,6 +56,10 @@ #define MISC_B_CLK_SEL_SHIFT 6 #define MISC_A_CLK_SEL_SHIFT 4 #define MISC_CLK_SEL_MASK 0x3 +#define MISC_B_CONSTANT_EN BIT(29) +#define MISC_A_CONSTANT_EN BIT(28) +#define MISC_B_INVERT_EN BIT(27) +#define MISC_A_INVERT_EN BIT(26) #define MISC_B_EN BIT(1) #define MISC_A_EN BIT(0) @@ -68,6 +72,8 @@ static struct meson_pwm_channel_data { u8 clk_div_shift; u8 clk_en_shift; u32 pwm_en_mask; + u32 const_en_mask; + u32 inv_en_mask; } meson_pwm_per_channel_data[MESON_NUM_PWMS] = { { .reg_offset = REG_PWM_A, @@ -75,6 +81,8 @@ static struct meson_pwm_channel_data { .clk_div_shift = MISC_A_CLK_DIV_SHIFT, .clk_en_shift = MISC_A_CLK_EN_SHIFT, .pwm_en_mask = MISC_A_EN, + .const_en_mask = MISC_A_CONSTANT_EN, + .inv_en_mask = MISC_A_INVERT_EN, }, { .reg_offset = REG_PWM_B, @@ -82,6 +90,8 @@ static struct meson_pwm_channel_data { .clk_div_shift = MISC_B_CLK_DIV_SHIFT, .clk_en_shift = MISC_B_CLK_EN_SHIFT, .pwm_en_mask = MISC_B_EN, + .const_en_mask = MISC_B_CONSTANT_EN, + .inv_en_mask = MISC_B_INVERT_EN, } }; @@ -89,6 +99,8 @@ struct meson_pwm_channel { unsigned long rate; unsigned int hi; unsigned int lo; + bool constant; + bool inverted; struct clk_mux mux; struct clk_divider div; @@ -99,6 +111,8 @@ struct meson_pwm_channel { struct meson_pwm_data { const char *const parent_names[MESON_NUM_MUX_PARENTS]; int (*channels_init)(struct pwm_chip *chip); + bool has_constant; + bool has_polarity; }; struct meson_pwm { @@ -160,7 +174,7 @@ static int meson_pwm_calc(struct pwm_chip *chip, struct pwm_device *pwm, * Fixing this needs some care however as some machines might rely on * this. */ - if (state->polarity == PWM_POLARITY_INVERSED) + if (state->polarity == PWM_POLARITY_INVERSED && !meson->data->has_polarity) duty = period - duty; freq = div64_u64(NSEC_PER_SEC * 0xffffULL, period); @@ -187,9 +201,11 @@ static int meson_pwm_calc(struct pwm_chip *chip, struct pwm_device *pwm, if (duty == period) { channel->hi = cnt; channel->lo = 0; + channel->constant = true; } else if (duty == 0) { channel->hi = 0; channel->lo = cnt; + channel->constant = true; } else { duty_cnt = mul_u64_u64_div_u64(fin_freq, duty, NSEC_PER_SEC); @@ -197,6 +213,7 @@ static int meson_pwm_calc(struct pwm_chip *chip, struct pwm_device *pwm, channel->hi = duty_cnt; channel->lo = cnt - duty_cnt; + channel->constant = false; } channel->rate = fin_freq; @@ -227,6 +244,19 @@ static void meson_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm) value = readl(meson->base + REG_MISC_AB); value |= channel_data->pwm_en_mask; + + if (meson->data->has_constant) { + value &= ~channel_data->const_en_mask; + if (channel->constant) + value |= channel_data->const_en_mask; + } + + if (meson->data->has_polarity) { + value &= ~channel_data->inv_en_mask; + if (channel->inverted) + value |= channel_data->inv_en_mask; + } + writel(value, meson->base + REG_MISC_AB); spin_unlock_irqrestore(&meson->lock, flags); @@ -235,13 +265,24 @@ static void meson_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm) static void meson_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm) { struct meson_pwm *meson = to_meson_pwm(chip); + struct meson_pwm_channel *channel = &meson->channels[pwm->hwpwm]; + struct meson_pwm_channel_data *channel_data; unsigned long flags; u32 value; + channel_data = &meson_pwm_per_channel_data[pwm->hwpwm]; + spin_lock_irqsave(&meson->lock, flags); value = readl(meson->base + REG_MISC_AB); - value &= ~meson_pwm_per_channel_data[pwm->hwpwm].pwm_en_mask; + value &= ~channel_data->pwm_en_mask; + + if (meson->data->has_polarity) { + value &= ~channel_data->inv_en_mask; + if (channel->inverted) + value |= channel_data->inv_en_mask; + } + writel(value, meson->base + REG_MISC_AB); spin_unlock_irqrestore(&meson->lock, flags); @@ -254,10 +295,12 @@ static int meson_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm, struct meson_pwm_channel *channel = &meson->channels[pwm->hwpwm]; int err = 0; + channel->inverted = (state->polarity == PWM_POLARITY_INVERSED); + if (!state->enabled) { - if (state->polarity == PWM_POLARITY_INVERSED) { + if (channel->inverted && !meson->data->has_polarity) { /* - * This IP block revision doesn't have an "always high" + * Some of IP block revisions don't have an "always high" * setting which we can use for "inverted disabled". * Instead we achieve this by setting mux parent with * highest rate and minimum divider value, resulting @@ -271,6 +314,7 @@ static int meson_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm, channel->rate = ULONG_MAX; channel->hi = ~0; channel->lo = 0; + channel->constant = true; meson_pwm_enable(chip, pwm); } else { @@ -287,21 +331,9 @@ static int meson_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm, return 0; } -static u64 meson_pwm_cnt_to_ns(struct pwm_chip *chip, struct pwm_device *pwm, - u32 cnt) +static u64 meson_pwm_cnt_to_ns(unsigned long fin_freq, u32 cnt) { - struct meson_pwm *meson = to_meson_pwm(chip); - struct meson_pwm_channel *channel; - unsigned long fin_freq; - - /* to_meson_pwm() can only be used after .get_state() is called */ - channel = &meson->channels[pwm->hwpwm]; - - fin_freq = clk_get_rate(channel->clk); - if (fin_freq == 0) - return 0; - - return div64_ul(NSEC_PER_SEC * (u64)cnt, fin_freq); + return fin_freq ? div64_ul(NSEC_PER_SEC * (u64)cnt, fin_freq) : 0; } static int meson_pwm_get_state(struct pwm_chip *chip, struct pwm_device *pwm, @@ -309,23 +341,27 @@ static int meson_pwm_get_state(struct pwm_chip *chip, struct pwm_device *pwm, { struct meson_pwm *meson = to_meson_pwm(chip); struct meson_pwm_channel_data *channel_data; - struct meson_pwm_channel *channel; + unsigned long fin_freq; + unsigned int hi, lo; u32 value; - channel = &meson->channels[pwm->hwpwm]; channel_data = &meson_pwm_per_channel_data[pwm->hwpwm]; + fin_freq = clk_get_rate(meson->channels[pwm->hwpwm].clk); value = readl(meson->base + REG_MISC_AB); state->enabled = value & channel_data->pwm_en_mask; - value = readl(meson->base + channel_data->reg_offset); - channel->lo = FIELD_GET(PWM_LOW_MASK, value); - channel->hi = FIELD_GET(PWM_HIGH_MASK, value); + if (meson->data->has_polarity && (value & channel_data->inv_en_mask)) + state->polarity = PWM_POLARITY_INVERSED; + else + state->polarity = PWM_POLARITY_NORMAL; - state->period = meson_pwm_cnt_to_ns(chip, pwm, channel->lo + channel->hi); - state->duty_cycle = meson_pwm_cnt_to_ns(chip, pwm, channel->hi); + value = readl(meson->base + channel_data->reg_offset); + lo = FIELD_GET(PWM_LOW_MASK, value); + hi = FIELD_GET(PWM_HIGH_MASK, value); - state->polarity = PWM_POLARITY_NORMAL; + state->period = meson_pwm_cnt_to_ns(fin_freq, lo + hi); + state->duty_cycle = meson_pwm_cnt_to_ns(fin_freq, hi); return 0; } @@ -508,29 +544,52 @@ static const struct meson_pwm_data pwm_gxbb_ao_data = { static const struct meson_pwm_data pwm_axg_ee_data = { .parent_names = { "xtal", "fclk_div5", "fclk_div4", "fclk_div3" }, .channels_init = meson_pwm_init_channels_meson8b_legacy, + .has_constant = true, + .has_polarity = true, }; static const struct meson_pwm_data pwm_axg_ao_data = { .parent_names = { "xtal", "axg_ao_clk81", "fclk_div4", "fclk_div5" }, .channels_init = meson_pwm_init_channels_meson8b_legacy, + .has_constant = true, + .has_polarity = true, +}; + +static const struct meson_pwm_data pwm_g12a_ee_data = { + .parent_names = { "xtal", NULL, "fclk_div4", "fclk_div3" }, + .channels_init = meson_pwm_init_channels_meson8b_legacy, + .has_constant = true, + .has_polarity = true, }; static const struct meson_pwm_data pwm_g12a_ao_ab_data = { .parent_names = { "xtal", "g12a_ao_clk81", "fclk_div4", "fclk_div5" }, .channels_init = meson_pwm_init_channels_meson8b_legacy, + .has_constant = true, + .has_polarity = true, }; static const struct meson_pwm_data pwm_g12a_ao_cd_data = { .parent_names = { "xtal", "g12a_ao_clk81", NULL, NULL }, .channels_init = meson_pwm_init_channels_meson8b_legacy, + .has_constant = true, + .has_polarity = true, }; static const struct meson_pwm_data pwm_meson8_v2_data = { .channels_init = meson_pwm_init_channels_meson8b_v2, }; +static const struct meson_pwm_data pwm_meson_axg_v2_data = { + .channels_init = meson_pwm_init_channels_meson8b_v2, + .has_constant = true, + .has_polarity = true, +}; + static const struct meson_pwm_data pwm_s4_data = { .channels_init = meson_pwm_init_channels_s4, + .has_constant = true, + .has_polarity = true, }; static const struct of_device_id meson_pwm_matches[] = { @@ -538,6 +597,14 @@ static const struct of_device_id meson_pwm_matches[] = { .compatible = "amlogic,meson8-pwm-v2", .data = &pwm_meson8_v2_data }, + { + .compatible = "amlogic,meson-axg-pwm-v2", + .data = &pwm_meson_axg_v2_data + }, + { + .compatible = "amlogic,meson-g12-pwm-v2", + .data = &pwm_meson_axg_v2_data + }, /* The following compatibles are obsolete */ { .compatible = "amlogic,meson8b-pwm", @@ -561,7 +628,7 @@ static const struct of_device_id meson_pwm_matches[] = { }, { .compatible = "amlogic,meson-g12a-ee-pwm", - .data = &pwm_meson8b_data + .data = &pwm_g12a_ee_data }, { .compatible = "amlogic,meson-g12a-ao-pwm-ab", |