Merge tag 'pwm/for-4.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/thierry.reding/linux-pwm

Pull pwm updates from Thierry Reding:
 "The changes for this release include a new driver for the PWM
  controller found on SoCs of the ZTX ZX family. Support for an old
  SH-Mobile SoC has been dropped and the Rockchip and MediaTek drivers
  gain support for more generations.

  Other than that there are a bunch of coding style fixes, minor bug
  fixes and cleanup as well as documentation patches"

* tag 'pwm/for-4.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/thierry.reding/linux-pwm: (32 commits)
  pwm: pwm-samsung: fix suspend/resume support
  pwm: samsung: Remove redundant checks from pwm_samsung_config()
  pwm: mediatek: Disable clock on PWM configuration failure
  dt-bindings: pwm: Add MT2712/MT7622 information
  pwm: mediatek: Fix clock control issue
  pwm: mediatek: Fix PWM source clock selection
  pwm: mediatek: Fix Kconfig description
  pwm: tegra: Explicitly request exclusive reset control
  pwm: hibvt: Explicitly request exclusive reset control
  pwm: tiehrpwm: Set driver data before runtime PM enable
  pwm: tiehrpwm: Miscellaneous coding style fixups
  pwm: tiecap: Set driver data before runtime PM enable
  pwm: tiecap: Miscellaneous coding style fixups
  dt-bindings: pwm: tiecap: Add TI 66AK2G SoC specific compatible
  pwm: tiehrpwm: fix clock imbalance in probe error path
  pwm: tiehrpwm: Fix runtime PM imbalance at unbind
  pwm: Kconfig: Enable pwm-tiecap to be built for Keystone
  pwm: Add ZTE ZX PWM device driver
  dt-bindings: pwm: Add bindings doc for ZTE ZX PWM controller
  pwm: bcm2835: Support for polarity setting via DT
  ...

1 files changed, 54 insertions, 24 deletions

diff --git a/drivers/pwm/pwm-mediatek.c b/drivers/pwm/pwm-mediatek.c
index 5c11bc7..b52f3af 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 <blogic@openwrt.org>
+ * Copyright (C) 2017 Zhi Mao <zhi.mao@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
@@ -29,6 +30,8 @@
 #define PWMDWIDTH		0x2c
 #define PWMTHRES		0x30
 
+#define PWM_CLK_DIV_MAX		7
+
 enum {
 	MTK_CLK_MAIN = 0,
 	MTK_CLK_TOP,
@@ -61,6 +64,42 @@ 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;
+
+	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 +119,11 @@ 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);
 
@@ -88,13 +132,18 @@ static int mtk_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
 		clkdiv++;
 	}
 
-	if (clkdiv > 7)
+	if (clkdiv > PWM_CLK_DIV_MAX) {
+		mtk_pwm_clk_disable(chip, pwm);
+		dev_err(chip->dev, "period %d not supported\n", period_ns);
 		return -EINVAL;
+	}
 
-	mtk_pwm_writel(pc, pwm->hwpwm, PWMCON, BIT(15) | BIT(3) | clkdiv);
+	mtk_pwm_writel(pc, pwm->hwpwm, PWMCON, BIT(15) | clkdiv);
 	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 +153,7 @@ 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 +173,7 @@ 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 +205,6 @@ 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 +215,15 @@ 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);
 }