[PATCH v2 08/14] pwm: meson: add the per-channel register offsets and bits in a struct

From: Martin Blumenstingl
Date: Sat Jun 08 2019 - 14:11:34 EST


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.

Signed-off-by: Martin Blumenstingl <martin.blumenstingl@xxxxxxxxxxxxxx>
Reviewed-by: Neil Armstrong <narmstrong@xxxxxxxxxxxx>
---
drivers/pwm/pwm-meson.c | 90 ++++++++++++++++-------------------------
1 file changed, 34 insertions(+), 56 deletions(-)

diff --git a/drivers/pwm/pwm-meson.c b/drivers/pwm/pwm-meson.c
index a4ae3587a3ce..ac7e188155fd 100644
--- 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;
@@ -458,7 +435,8 @@ 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;
--
2.21.0