[PATCH 2/4] pwm: rockchip: Allow polarity invert on rk3288
From: dianders@chromium.org (Doug Anderson)
Date: 2014-08-18 17:09:21
Also in:
linux-devicetree, linux-pwm, lkml
Subsystem:
arm/rockchip soc support, open firmware and flattened device tree bindings, pwm subsystem, the rest · Maintainers:
Heiko Stuebner, Rob Herring, Krzysztof Kozlowski, Conor Dooley, Uwe Kleine-König, Linus Torvalds
The rk3288 has the ability to invert the polarity of the PWM. Let's enable that ability. To do this we increase the number of pwm_cells to 3 to allow using the PWM_POLARITY_INVERTED flag. Since the PWM driver on rk3288 is very new, I thought this was OK. Signed-off-by: Doug Anderson <dianders@chromium.org> --- .../devicetree/bindings/pwm/pwm-rockchip.txt | 4 +-- drivers/pwm/pwm-rockchip.c | 32 ++++++++++++++++++++-- 2 files changed, 32 insertions(+), 4 deletions(-)
diff --git a/Documentation/devicetree/bindings/pwm/pwm-rockchip.txt b/Documentation/devicetree/bindings/pwm/pwm-rockchip.txt
index d47d15a..b8be3d0 100644
--- a/Documentation/devicetree/bindings/pwm/pwm-rockchip.txt
+++ b/Documentation/devicetree/bindings/pwm/pwm-rockchip.txt@@ -7,8 +7,8 @@ Required properties: "rockchip,vop-pwm": found integrated in VOP on RK3288 SoC - reg: physical base address and length of the controller's registers - clocks: phandle and clock specifier of the PWM reference clock - - #pwm-cells: should be 2. See pwm.txt in this directory for a - description of the cell format. + - #pwm-cells: must be 2 (rk2928) or 3 (rk3288). See pwm.txt in this directory + for a description of the cell format. Example:
diff --git a/drivers/pwm/pwm-rockchip.c b/drivers/pwm/pwm-rockchip.c
index bdd8644..27f20d6 100644
--- a/drivers/pwm/pwm-rockchip.c
+++ b/drivers/pwm/pwm-rockchip.c@@ -24,7 +24,9 @@ #define PWM_ENABLE (1 << 0) #define PWM_CONTINUOUS (1 << 1) #define PWM_DUTY_POSITIVE (1 << 3) +#define PWM_DUTY_NEGATIVE (0 << 3) #define PWM_INACTIVE_NEGATIVE (0 << 4) +#define PWM_INACTIVE_POSITIVE (1 << 4) #define PWM_OUTPUT_LEFT (0 << 5) #define PWM_LP_DISABLE (0 << 8)
@@ -32,6 +34,7 @@ struct rockchip_pwm_chip { struct pwm_chip chip; struct clk *clk; const struct rockchip_pwm_data *data; + enum pwm_polarity polarity; void __iomem *base; };
@@ -45,6 +48,7 @@ struct rockchip_pwm_regs { struct rockchip_pwm_data { struct rockchip_pwm_regs regs; unsigned int prescaler; + bool has_invert; void (*set_enable)(struct pwm_chip *chip, bool enable); };
@@ -74,10 +78,14 @@ static void rockchip_pwm_set_enable_v2(struct pwm_chip *chip, bool enable) { struct rockchip_pwm_chip *pc = to_rockchip_pwm_chip(chip); u32 enable_conf = PWM_OUTPUT_LEFT | PWM_LP_DISABLE | PWM_ENABLE | - PWM_CONTINUOUS | PWM_DUTY_POSITIVE | - PWM_INACTIVE_NEGATIVE; + PWM_CONTINUOUS; u32 val; + if (pc->polarity == PWM_POLARITY_INVERSED) + enable_conf |= PWM_DUTY_NEGATIVE | PWM_INACTIVE_POSITIVE; + else + enable_conf |= PWM_DUTY_POSITIVE | PWM_INACTIVE_NEGATIVE; + val = readl_relaxed(pc->base + pc->data->regs.ctrl); if (enable)
@@ -124,6 +132,19 @@ static int rockchip_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm, return 0; } +int rockchip_pwm_set_polarity(struct pwm_chip *chip, struct pwm_device *pwm, + enum pwm_polarity polarity) +{ + struct rockchip_pwm_chip *pc = to_rockchip_pwm_chip(chip); + + if (!pc->data->has_invert) + return -ENOSYS; + + pc->polarity = polarity; + + return 0; +} + static int rockchip_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm) { struct rockchip_pwm_chip *pc = to_rockchip_pwm_chip(chip);
@@ -149,6 +170,7 @@ static void rockchip_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm) static const struct pwm_ops rockchip_pwm_ops = { .config = rockchip_pwm_config, + .set_polarity = rockchip_pwm_set_polarity, .enable = rockchip_pwm_enable, .disable = rockchip_pwm_disable, .owner = THIS_MODULE,
@@ -173,6 +195,7 @@ static const struct rockchip_pwm_data pwm_data_v2 = { .ctrl = 0x0c, }, .prescaler = 1, + .has_invert = 1, .set_enable = rockchip_pwm_set_enable_v2, };
@@ -184,6 +207,7 @@ static const struct rockchip_pwm_data pwm_data_vop = { .ctrl = 0x00, }, .prescaler = 1, + .has_invert = 1, .set_enable = rockchip_pwm_set_enable_v2, };
@@ -228,6 +252,10 @@ static int rockchip_pwm_probe(struct platform_device *pdev) pc->data = id->data; pc->chip.dev = &pdev->dev; pc->chip.ops = &rockchip_pwm_ops; + if (pc->data->has_invert) { + pc->chip.of_xlate = of_pwm_xlate_with_flags; + pc->chip.of_pwm_n_cells = 3; + } pc->chip.base = -1; pc->chip.npwm = 1;
--
2.1.0.rc2.206.gedb03e5