pwm: meson: Add the per-channel register offsets and bits in a struct

Introduce struct meson_pwm_channel_data which contains the per-channel
offsets for the PWM register and REG_MISC_AB bits. Replace the existing
switch (pwm->hwpwm) statements with an access to the new struct.

This simplifies the code and will make it easier to implement
pwm_ops.get_state() because the switch-case which all per-channel
registers and offsets (as previously implemented in meson_pwm_enable())
doesn't have to be duplicated.

No functional changes intended.

Reviewed-by: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

diff --git a/drivers/pwm/pwm-meson.c b/drivers/pwm/pwm-meson.c
index 207e594c2d9917f78896e42834a9c5c291f6de85..56f603e8023a0084411fb7255057bc1ed2693da4 100644 (file)
--- a/drivers/pwm/pwm-meson.c
+++ b/drivers/pwm/pwm-meson.c
@@ -39,9 +39,27 @@
 
 #define MESON_NUM_PWMS         2
 
-static const unsigned int mux_reg_shifts[] = {
-       MISC_A_CLK_SEL_SHIFT,
-       MISC_B_CLK_SEL_SHIFT
+static struct meson_pwm_channel_data {
+       u8              reg_offset;
+       u8              clk_sel_shift;
+       u8              clk_div_shift;
+       u32             clk_en_mask;
+       u32             pwm_en_mask;
+} meson_pwm_per_channel_data[MESON_NUM_PWMS] = {
+       {
+               .reg_offset     = REG_PWM_A,
+               .clk_sel_shift  = MISC_A_CLK_SEL_SHIFT,
+               .clk_div_shift  = MISC_A_CLK_DIV_SHIFT,
+               .clk_en_mask    = MISC_A_CLK_EN,
+               .pwm_en_mask    = MISC_A_EN,
+       },
+       {
+               .reg_offset     = REG_PWM_B,
+               .clk_sel_shift  = MISC_B_CLK_SEL_SHIFT,
+               .clk_div_shift  = MISC_B_CLK_DIV_SHIFT,
+               .clk_en_mask    = MISC_B_CLK_EN,
+               .pwm_en_mask    = MISC_B_EN,
+       }
 };
 
 struct meson_pwm_channel {
@@ -194,43 +212,26 @@ static int meson_pwm_calc(struct meson_pwm *meson, struct pwm_device *pwm,
 static void meson_pwm_enable(struct meson_pwm *meson, struct pwm_device *pwm)
 {
        struct meson_pwm_channel *channel = pwm_get_chip_data(pwm);
-       u32 value, clk_shift, clk_enable, enable;
-       unsigned int offset;
+       struct meson_pwm_channel_data *channel_data;
        unsigned long flags;
+       u32 value;
 
-       switch (pwm->hwpwm) {
-       case 0:
-               clk_shift = MISC_A_CLK_DIV_SHIFT;
-               clk_enable = MISC_A_CLK_EN;
-               enable = MISC_A_EN;
-               offset = REG_PWM_A;
-               break;
-
-       case 1:
-               clk_shift = MISC_B_CLK_DIV_SHIFT;
-               clk_enable = MISC_B_CLK_EN;
-               enable = MISC_B_EN;
-               offset = REG_PWM_B;
-               break;
-
-       default:
-               return;
-       }
+       channel_data = &meson_pwm_per_channel_data[pwm->hwpwm];
 
        spin_lock_irqsave(&meson->lock, flags);
 
        value = readl(meson->base + REG_MISC_AB);
-       value &= ~(MISC_CLK_DIV_MASK << clk_shift);
-       value |= channel->pre_div << clk_shift;
-       value |= clk_enable;
+       value &= ~(MISC_CLK_DIV_MASK << channel_data->clk_div_shift);
+       value |= channel->pre_div << channel_data->clk_div_shift;
+       value |= channel_data->clk_en_mask;
        writel(value, meson->base + REG_MISC_AB);
 
        value = FIELD_PREP(PWM_HIGH_MASK, channel->hi) |
                FIELD_PREP(PWM_LOW_MASK, channel->lo);
-       writel(value, meson->base + offset);
+       writel(value, meson->base + channel_data->reg_offset);
 
        value = readl(meson->base + REG_MISC_AB);
-       value |= enable;
+       value |= channel_data->pwm_en_mask;
        writel(value, meson->base + REG_MISC_AB);
 
        spin_unlock_irqrestore(&meson->lock, flags);
@@ -238,26 +239,13 @@ static void meson_pwm_enable(struct meson_pwm *meson, struct pwm_device *pwm)
 
 static void meson_pwm_disable(struct meson_pwm *meson, struct pwm_device *pwm)
 {
-       u32 value, enable;
        unsigned long flags;
-
-       switch (pwm->hwpwm) {
-       case 0:
-               enable = MISC_A_EN;
-               break;
-
-       case 1:
-               enable = MISC_B_EN;
-               break;
-
-       default:
-               return;
-       }
+       u32 value;
 
        spin_lock_irqsave(&meson->lock, flags);
 
        value = readl(meson->base + REG_MISC_AB);
-       value &= ~enable;
+       value &= ~meson_pwm_per_channel_data[pwm->hwpwm].pwm_en_mask;
        writel(value, meson->base + REG_MISC_AB);
 
        spin_unlock_irqrestore(&meson->lock, flags);
@@ -309,18 +297,7 @@ static void meson_pwm_get_state(struct pwm_chip *chip, struct pwm_device *pwm,
        if (!state)
                return;
 
-       switch (pwm->hwpwm) {
-       case 0:
-               mask = MISC_A_EN;
-               break;
-
-       case 1:
-               mask = MISC_B_EN;
-               break;
-
-       default:
-               return;
-       }
+       mask = meson_pwm_per_channel_data[pwm->hwpwm].pwm_en_mask;
 
        value = readl(meson->base + REG_MISC_AB);
        state->enabled = (value & mask) != 0;
@@ -467,7 +444,8 @@ static int meson_pwm_init_channels(struct meson_pwm *meson)
                init.num_parents = meson->data->num_parents;
 
                channel->mux.reg = meson->base + REG_MISC_AB;
-               channel->mux.shift = mux_reg_shifts[i];
+               channel->mux.shift =
+                               meson_pwm_per_channel_data[i].clk_sel_shift;
                channel->mux.mask = MISC_CLK_SEL_MASK;
                channel->mux.flags = 0;
                channel->mux.lock = &meson->lock;