[v5,2/3] pwm: mtk_disp: implement atomic API .apply()

Message ID	20210616085224.157318-3-jitao.shi@mediatek.com
State	Changes Requested
Headers	show Return-Path: <linux-pwm-owner@vger.kernel.org> From: Jitao Shi <jitao.shi@mediatek.com> To: Thierry Reding <thierry.reding@gmail.com>, Lee Jones <lee.jones@linaro.org>, =?utf-8?q?Uwe_Kleine-K=C3=B6nig?= <u.kleine-koenig@pengutronix.de>, Matthias Brugger <matthias.bgg@gmail.com> CC: <linux-pwm@vger.kernel.org>, <linux-arm-kernel@lists.infradead.org>, <linux-mediatek@lists.infradead.org>, <linux-kernel@vger.kernel.org>, <srv_heupstream@mediatek.com>, <yingjoe.chen@mediatek.com>, <eddie.huang@mediatek.com>, <cawa.cheng@mediatek.com>, <bibby.hsieh@mediatek.com>, <ck.hu@mediatek.com>, <stonea168@163.com>, <huijuan.xie@mediatek.com>, Jitao Shi <jitao.shi@mediatek.com> Subject: [PATCH v5 2/3] pwm: mtk_disp: implement atomic API .apply() Date: Wed, 16 Jun 2021 16:52:23 +0800 Message-ID: <20210616085224.157318-3-jitao.shi@mediatek.com> In-Reply-To: <20210616085224.157318-1-jitao.shi@mediatek.com> References: <20210616085224.157318-1-jitao.shi@mediatek.com> MIME-Version: 1.0 Content-Type: text/plain Content-Transfer-Encoding: base64 Precedence: bulk
Series	fix the clks on/off mismatch issue and switch pwm-mtk-disp to atomic APIs \| expand [v5,0/3] fix the clks on/off mismatch issue and switch pwm-mtk-disp to atomic APIs [v5,1/3] pwm: mtk-disp: adjust the clocks to avoid them mismatch [v5,2/3] pwm: mtk_disp: implement atomic API .apply() [v5,3/3] pwm: mtk_disp: implement atomic API .get_state()

Message ID

20210616085224.157318-3-jitao.shi@mediatek.com

State

Changes Requested

Headers

From: Jitao Shi <jitao.shi@mediatek.com>
To: Thierry Reding <thierry.reding@gmail.com>,
 Lee Jones <lee.jones@linaro.org>,
 =?utf-8?q?Uwe_Kleine-K=C3=B6nig?=  <u.kleine-koenig@pengutronix.de>,
 Matthias Brugger <matthias.bgg@gmail.com>
CC: <linux-pwm@vger.kernel.org>,
        <linux-arm-kernel@lists.infradead.org>,
        <linux-mediatek@lists.infradead.org>,
        <linux-kernel@vger.kernel.org>, <srv_heupstream@mediatek.com>,
        <yingjoe.chen@mediatek.com>, <eddie.huang@mediatek.com>,
        <cawa.cheng@mediatek.com>, <bibby.hsieh@mediatek.com>,
        <ck.hu@mediatek.com>, <stonea168@163.com>,
        <huijuan.xie@mediatek.com>, Jitao Shi <jitao.shi@mediatek.com>
Subject: [PATCH v5 2/3] pwm: mtk_disp: implement atomic API .apply()
Date: Wed, 16 Jun 2021 16:52:23 +0800
Message-ID: <20210616085224.157318-3-jitao.shi@mediatek.com>
In-Reply-To: <20210616085224.157318-1-jitao.shi@mediatek.com>
References: <20210616085224.157318-1-jitao.shi@mediatek.com>
MIME-Version: 1.0
Content-Type: text/plain
Content-Transfer-Encoding: base64
Precedence: bulk

Series

fix the clks on/off mismatch issue and switch pwm-mtk-disp to atomic APIs | expand

Switch the driver to support the .apply() method. Signed-off-by: Jitao Shi <jitao.shi@mediatek.com> --- drivers/pwm/pwm-mtk-disp.c | 69 ++++++++++---------------------------- 1 file changed, 17 insertions(+), 52 deletions(-)

Comments

Uwe Kleine-König June 25, 2021, 5:52 p.m. UTC | #1

On Wed, Jun 16, 2021 at 04:52:23PM +0800, Jitao Shi wrote:
> Switch the driver to support the .apply() method.
> 
> Signed-off-by: Jitao Shi <jitao.shi@mediatek.com>
> ---
>  drivers/pwm/pwm-mtk-disp.c | 69 ++++++++++----------------------------
>  1 file changed, 17 insertions(+), 52 deletions(-)
> 
> diff --git a/drivers/pwm/pwm-mtk-disp.c b/drivers/pwm/pwm-mtk-disp.c
> index 204d76beeb26..a4766e931b68 100644
> --- a/drivers/pwm/pwm-mtk-disp.c
> +++ b/drivers/pwm/pwm-mtk-disp.c
> @@ -67,14 +67,25 @@ static void mtk_disp_pwm_update_bits(struct mtk_disp_pwm *mdp, u32 offset,
>  	writel(value, address);
>  }
>  
> -static int mtk_disp_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
> -			       int duty_ns, int period_ns)
> +static int mtk_disp_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm,
> +			      const struct pwm_state *state)
>  {
>  	struct mtk_disp_pwm *mdp = to_mtk_disp_pwm(chip);
>  	u32 clk_div, period, high_width, value;
>  	u64 div, rate;
>  	int err;
>  

Here something like:

	if (state->polarity != PWM_POLARITY_NORMAL)
		return -EINVAL;

is missing.

> +	if (!state->enabled) {
> +		mtk_disp_pwm_update_bits(mdp, DISP_PWM_EN, mdp->data->enable_mask,
> +					 0x0);
> +		if (mdp->enabled) {
> +			clk_disable_unprepare(mdp->clk_mm);
> +			clk_disable_unprepare(mdp->clk_main);
> +		}
> +		mdp->enabled = false;
> +		return 0;
> +	}
> +
>  	if (!mdp->enabled) {
>  		err = clk_prepare_enable(mdp->clk_main);
>  		if (err < 0) {
> @@ -102,7 +113,7 @@ static int mtk_disp_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
>  	 * high_width = (PWM_CLK_RATE * duty_ns) / (10^9 * (clk_div + 1))
>  	 */
>  	rate = clk_get_rate(mdp->clk_main);
> -	clk_div = div_u64(rate * period_ns, NSEC_PER_SEC) >>
> +	clk_div = div_u64(rate * state->period, NSEC_PER_SEC) >>

This multiplication might overflow. But maybe it's sensible to address
this in a separate commit to keep things simple.

>  			  PWM_PERIOD_BIT_WIDTH;
>  	if (clk_div > PWM_CLKDIV_MAX) {
>  		if (!mdp->enabled) {
> @@ -112,11 +123,11 @@ static int mtk_disp_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
>  		return -EINVAL;
>  	}
>  	div = NSEC_PER_SEC * (clk_div + 1);
> -	period = div64_u64(rate * period_ns, div);
> +	period = div64_u64(rate * state->period, div);

ditto.

Best regards
Uwe

diff --git a/drivers/pwm/pwm-mtk-disp.c b/drivers/pwm/pwm-mtk-disp.c
index 204d76beeb26..a4766e931b68 100644
--- a/drivers/pwm/pwm-mtk-disp.c
+++ b/drivers/pwm/pwm-mtk-disp.c
@@ -67,14 +67,25 @@  static void mtk_disp_pwm_update_bits(struct mtk_disp_pwm *mdp, u32 offset,
 	writel(value, address);
 }
 
-static int mtk_disp_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
-			       int duty_ns, int period_ns)
+static int mtk_disp_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm,
+			      const struct pwm_state *state)
 {
 	struct mtk_disp_pwm *mdp = to_mtk_disp_pwm(chip);
 	u32 clk_div, period, high_width, value;
 	u64 div, rate;
 	int err;
 
+	if (!state->enabled) {
+		mtk_disp_pwm_update_bits(mdp, DISP_PWM_EN, mdp->data->enable_mask,
+					 0x0);
+		if (mdp->enabled) {
+			clk_disable_unprepare(mdp->clk_mm);
+			clk_disable_unprepare(mdp->clk_main);
+		}
+		mdp->enabled = false;
+		return 0;
+	}
+
 	if (!mdp->enabled) {
 		err = clk_prepare_enable(mdp->clk_main);
 		if (err < 0) {
@@ -102,7 +113,7 @@  static int mtk_disp_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
 	 * high_width = (PWM_CLK_RATE * duty_ns) / (10^9 * (clk_div + 1))
 	 */
 	rate = clk_get_rate(mdp->clk_main);
-	clk_div = div_u64(rate * period_ns, NSEC_PER_SEC) >>
+	clk_div = div_u64(rate * state->period, NSEC_PER_SEC) >>
 			  PWM_PERIOD_BIT_WIDTH;
 	if (clk_div > PWM_CLKDIV_MAX) {
 		if (!mdp->enabled) {
@@ -112,11 +123,11 @@  static int mtk_disp_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
 		return -EINVAL;
 	}
 	div = NSEC_PER_SEC * (clk_div + 1);
-	period = div64_u64(rate * period_ns, div);
+	period = div64_u64(rate * state->period, div);
 	if (period > 0)
 		period--;
 
-	high_width = div64_u64(rate * duty_ns, div);
+	high_width = div64_u64(rate * state->duty_cycle, div);
 	value = period | (high_width << PWM_HIGH_WIDTH_SHIFT);
 
 	mtk_disp_pwm_update_bits(mdp, mdp->data->con0,
@@ -141,36 +152,6 @@  static int mtk_disp_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
 					 mdp->data->con0_sel,
 					 mdp->data->con0_sel);
 	}
-
-	if (!mdp->enabled) {
-		clk_disable_unprepare(mdp->clk_mm);
-		clk_disable_unprepare(mdp->clk_main);
-	}
-
-	return 0;
-}
-
-static int mtk_disp_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm)
-{
-	struct mtk_disp_pwm *mdp = to_mtk_disp_pwm(chip);
-	int err;
-
-	if (!mdp->enabled) {
-		err = clk_prepare_enable(mdp->clk_main);
-		if (err < 0) {
-			dev_err(chip->dev, "Can't enable mdp->clk_main: %pe\n",
-				ERR_PTR(err));
-			return err;
-		}
-		err = clk_prepare_enable(mdp->clk_mm);
-		if (err < 0) {
-			dev_err(chip->dev, "Can't enable mdp->clk_mm: %pe\n",
-				ERR_PTR(err));
-			clk_disable_unprepare(mdp->clk_main);
-			return err;
-		}
-	}
-
 	mtk_disp_pwm_update_bits(mdp, DISP_PWM_EN, mdp->data->enable_mask,
 				 mdp->data->enable_mask);
 	mdp->enabled = true;
@@ -178,24 +159,8 @@  static int mtk_disp_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm)
 	return 0;
 }
 
-static void mtk_disp_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm)
-{
-	struct mtk_disp_pwm *mdp = to_mtk_disp_pwm(chip);
-
-	mtk_disp_pwm_update_bits(mdp, DISP_PWM_EN, mdp->data->enable_mask,
-				 0x0);
-
-	if (mdp->enabled) {
-		clk_disable_unprepare(mdp->clk_mm);
-		clk_disable_unprepare(mdp->clk_main);
-	}
-	mdp->enabled = false;
-}
-
 static const struct pwm_ops mtk_disp_pwm_ops = {
-	.config = mtk_disp_pwm_config,
-	.enable = mtk_disp_pwm_enable,
-	.disable = mtk_disp_pwm_disable,
+	.apply = mtk_disp_pwm_apply,
 	.owner = THIS_MODULE,
 };

[v5,2/3] pwm: mtk_disp: implement atomic API .apply()

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