1. prepare top/main clk in mtk_pwm_probe() function,
it will increase power consumption
and in original code these clocks is only prepeare but never enabled
2. pwm clock should be enabled before setting pwm registers
in function: mtk_pwm_config()
3. delete "pwm_disable" in function:mtk_pwm_remove(),
as framework should disable all the pwms, before remove them.
Signed-off-by: Zhi Mao <zhi....@mediatek.com>
---
drivers/pwm/pwm-mediatek.c | 69 ++++++++++++++++++++++++++++++--------------
1 file changed, 47 insertions(+), 22 deletions(-)
diff --git a/drivers/pwm/pwm-mediatek.c b/drivers/pwm/pwm-mediatek.c
index d08b5b3..554a042 100644
--- a/drivers/pwm/pwm-mediatek.c
+++ b/drivers/pwm/pwm-mediatek.c
@@ -2,6 +2,7 @@
* Mediatek Pulse Width Modulator driver
*
* Copyright (C) 2015 John Crispin <blo...@openwrt.org>
+ * Copyright (C) 2017 Zhi Mao <zhi....@mediatek.com>
*
* This file is licensed under the terms of the GNU General Public
* License version 2. This program is licensed "as is" without any
@@ -61,6 +62,42 @@ static inline struct mtk_pwm_chip *to_mtk_pwm_chip(struct
pwm_chip *chip)
return container_of(chip, struct mtk_pwm_chip, chip);
}
+static int mtk_pwm_clk_enable(struct pwm_chip *chip, struct pwm_device *pwm)
+{
+ struct mtk_pwm_chip *pc = to_mtk_pwm_chip(chip);
+ int ret = 0;
+
+ ret = clk_prepare_enable(pc->clks[MTK_CLK_TOP]);
+ if (ret < 0)
+ return ret;
+
+ ret = clk_prepare_enable(pc->clks[MTK_CLK_MAIN]);
+ if (ret < 0)
+ goto disable_clk_top;
+
+ ret = clk_prepare_enable(pc->clks[MTK_CLK_PWM1 + pwm->hwpwm]);
+ if (ret < 0)
+ goto disable_clk_main;
+
+ return 0;
+
+disable_clk_main:
+ clk_disable_unprepare(pc->clks[MTK_CLK_MAIN]);
+disable_clk_top:
+ clk_disable_unprepare(pc->clks[MTK_CLK_TOP]);
+
+ return ret;
+}
+
+static void mtk_pwm_clk_disable(struct pwm_chip *chip, struct pwm_device *pwm)
+{
+ struct mtk_pwm_chip *pc = to_mtk_pwm_chip(chip);
+
+ clk_disable_unprepare(pc->clks[MTK_CLK_PWM1 + pwm->hwpwm]);
+ clk_disable_unprepare(pc->clks[MTK_CLK_MAIN]);
+ clk_disable_unprepare(pc->clks[MTK_CLK_TOP]);
+}
+
static inline u32 mtk_pwm_readl(struct mtk_pwm_chip *chip, unsigned int num,
unsigned int offset)
{
@@ -80,6 +117,11 @@ static int mtk_pwm_config(struct pwm_chip *chip, struct
pwm_device *pwm,
struct mtk_pwm_chip *pc = to_mtk_pwm_chip(chip);
struct clk *clk = pc->clks[MTK_CLK_PWM1 + pwm->hwpwm];
u32 resolution, clkdiv = 0;
+ int ret;
+
+ ret = mtk_pwm_clk_enable(chip, pwm);
+ if (ret < 0)
+ return ret;
resolution = NSEC_PER_SEC / clk_get_rate(clk);
@@ -95,6 +137,8 @@ static int mtk_pwm_config(struct pwm_chip *chip, struct
pwm_device *pwm,
mtk_pwm_writel(pc, pwm->hwpwm, PWMDWIDTH, period_ns / resolution);
mtk_pwm_writel(pc, pwm->hwpwm, PWMTHRES, duty_ns / resolution);
+ mtk_pwm_clk_disable(chip, pwm);
+
return 0;
}
@@ -104,7 +148,7 @@ static int mtk_pwm_enable(struct pwm_chip *chip, struct
pwm_device *pwm)
u32 value;
int ret;
- ret = clk_prepare(pc->clks[MTK_CLK_PWM1 + pwm->hwpwm]);
+ ret = mtk_pwm_clk_enable(chip, pwm);
if (ret < 0)
return ret;
@@ -124,7 +168,7 @@ static void mtk_pwm_disable(struct pwm_chip *chip, struct
pwm_device *pwm)
value &= ~BIT(pwm->hwpwm);
writel(value, pc->regs);
- clk_unprepare(pc->clks[MTK_CLK_PWM1 + pwm->hwpwm]);
+ mtk_pwm_clk_disable(chip, pwm);
}
static const struct pwm_ops mtk_pwm_ops = {
@@ -156,14 +200,6 @@ static int mtk_pwm_probe(struct platform_device *pdev)
return PTR_ERR(pc->clks[i]);
}
- ret = clk_prepare(pc->clks[MTK_CLK_TOP]);
- if (ret < 0)
- return ret;
-
- ret = clk_prepare(pc->clks[MTK_CLK_MAIN]);
- if (ret < 0)
- goto disable_clk_top;
-
platform_set_drvdata(pdev, pc);
pc->chip.dev = &pdev->dev;
@@ -174,26 +210,15 @@ static int mtk_pwm_probe(struct platform_device *pdev)
ret = pwmchip_add(&pc->chip);
if (ret < 0) {
dev_err(&pdev->dev, "pwmchip_add() failed: %d\n", ret);
- goto disable_clk_main;
+ return ret;
}
return 0;
-
-disable_clk_main:
- clk_unprepare(pc->clks[MTK_CLK_MAIN]);
-disable_clk_top:
- clk_unprepare(pc->clks[MTK_CLK_TOP]);
-
- return ret;
}
static int mtk_pwm_remove(struct platform_device *pdev)
{
struct mtk_pwm_chip *pc = platform_get_drvdata(pdev);
- unsigned int i;
-
- for (i = 0; i < pc->chip.npwm; i++)
- pwm_disable(&pc->chip.pwms[i]);
return pwmchip_remove(&pc->chip);
}
--
1.7.9.5
