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authorDavid Wu <david.wu@rock-chips.com>2017-08-08 18:42:47 +0300
committerThierry Reding <thierry.reding@gmail.com>2017-08-18 18:44:34 +0300
commit3f9a363133eae0d01e77200af4ce9b58a4a9fc24 (patch)
tree6fb6401fdebe25b8be39c7e06ad3602438a9ad05 /drivers/pwm
parent831b2790507b3aac3213e9f39c714d85b0220098 (diff)
downloadlinux-3f9a363133eae0d01e77200af4ce9b58a4a9fc24.tar.xz
pwm: rockchip: Add rk3328 support
The rk3328 SoC supports atomic update, we could lock the configuration of period and duty at first, after unlock is configured, the period and duty are effective at the same time. If the polarity, period and duty need to be configured together, the way for atomic update is "configure lock and old polarity" -> "configure period and duty" -> "configure unlock and new polarity". Signed-off-by: David Wu <david.wu@rock-chips.com> Acked-by: Rob Herring <robh@kernel.org> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Diffstat (limited to 'drivers/pwm')
-rw-r--r--drivers/pwm/pwm-rockchip.c43
1 files changed, 41 insertions, 2 deletions
diff --git a/drivers/pwm/pwm-rockchip.c b/drivers/pwm/pwm-rockchip.c
index a3fcb404036d..4d99d468df09 100644
--- a/drivers/pwm/pwm-rockchip.c
+++ b/drivers/pwm/pwm-rockchip.c
@@ -29,6 +29,7 @@
#define PWM_INACTIVE_POSITIVE (1 << 4)
#define PWM_POLARITY_MASK (PWM_DUTY_POSITIVE | PWM_INACTIVE_POSITIVE)
#define PWM_OUTPUT_LEFT (0 << 5)
+#define PWM_LOCK_EN (1 << 6)
#define PWM_LP_DISABLE (0 << 8)
struct rockchip_pwm_chip {
@@ -50,6 +51,7 @@ struct rockchip_pwm_data {
struct rockchip_pwm_regs regs;
unsigned int prescaler;
bool supports_polarity;
+ bool supports_lock;
u32 enable_conf;
};
@@ -121,10 +123,19 @@ static void rockchip_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
div = clk_rate * state->duty_cycle;
duty = DIV_ROUND_CLOSEST_ULL(div, pc->data->prescaler * NSEC_PER_SEC);
+ /*
+ * Lock the period and duty of previous configuration, then
+ * change the duty and period, that would not be effective.
+ */
+ ctrl = readl_relaxed(pc->base + pc->data->regs.ctrl);
+ if (pc->data->supports_lock) {
+ ctrl |= PWM_LOCK_EN;
+ writel_relaxed(ctrl, pc->base + pc->data->regs.ctrl);
+ }
+
writel(period, pc->base + pc->data->regs.period);
writel(duty, pc->base + pc->data->regs.duty);
- ctrl = readl_relaxed(pc->base + pc->data->regs.ctrl);
if (pc->data->supports_polarity) {
ctrl &= ~PWM_POLARITY_MASK;
if (state->polarity == PWM_POLARITY_INVERSED)
@@ -132,6 +143,15 @@ static void rockchip_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
else
ctrl |= PWM_DUTY_POSITIVE | PWM_INACTIVE_NEGATIVE;
}
+
+ /*
+ * Unlock and set polarity at the same time,
+ * the configuration of duty, period and polarity
+ * would be effective together at next period.
+ */
+ if (pc->data->supports_lock)
+ ctrl &= ~PWM_LOCK_EN;
+
writel(ctrl, pc->base + pc->data->regs.ctrl);
}
@@ -180,7 +200,8 @@ static int rockchip_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm,
pwm_get_state(pwm, &curstate);
enabled = curstate.enabled;
- if (state->polarity != curstate.polarity && enabled) {
+ if (state->polarity != curstate.polarity && enabled &&
+ !pc->data->supports_lock) {
ret = rockchip_pwm_enable(chip, pwm, false);
if (ret)
goto out;
@@ -221,6 +242,7 @@ static const struct rockchip_pwm_data pwm_data_v1 = {
},
.prescaler = 2,
.supports_polarity = false,
+ .supports_lock = false,
.enable_conf = PWM_CTRL_OUTPUT_EN | PWM_CTRL_TIMER_EN,
};
@@ -233,6 +255,7 @@ static const struct rockchip_pwm_data pwm_data_v2 = {
},
.prescaler = 1,
.supports_polarity = true,
+ .supports_lock = false,
.enable_conf = PWM_OUTPUT_LEFT | PWM_LP_DISABLE | PWM_ENABLE |
PWM_CONTINUOUS,
};
@@ -246,6 +269,21 @@ static const struct rockchip_pwm_data pwm_data_vop = {
},
.prescaler = 1,
.supports_polarity = true,
+ .supports_lock = false,
+ .enable_conf = PWM_OUTPUT_LEFT | PWM_LP_DISABLE | PWM_ENABLE |
+ PWM_CONTINUOUS,
+};
+
+static const struct rockchip_pwm_data pwm_data_v3 = {
+ .regs = {
+ .duty = 0x08,
+ .period = 0x04,
+ .cntr = 0x00,
+ .ctrl = 0x0c,
+ },
+ .prescaler = 1,
+ .supports_polarity = true,
+ .supports_lock = true,
.enable_conf = PWM_OUTPUT_LEFT | PWM_LP_DISABLE | PWM_ENABLE |
PWM_CONTINUOUS,
};
@@ -254,6 +292,7 @@ static const struct of_device_id rockchip_pwm_dt_ids[] = {
{ .compatible = "rockchip,rk2928-pwm", .data = &pwm_data_v1},
{ .compatible = "rockchip,rk3288-pwm", .data = &pwm_data_v2},
{ .compatible = "rockchip,vop-pwm", .data = &pwm_data_vop},
+ { .compatible = "rockchip,rk3328-pwm", .data = &pwm_data_v3},
{ /* sentinel */ }
};
MODULE_DEVICE_TABLE(of, rockchip_pwm_dt_ids);