From: 许盛飞 <xsf@rock-chips.com>
Date: Tue, 2 Sep 2014 11:51:09 +0000 (+0800)
Subject: pwm: to solve the bug :
X-Git-Tag: firefly_0821_release~4769^2~1
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=6e2002dd9c8cb1dd2380312f9854e92a071e2e15;p=firefly-linux-kernel-4.4.55.git

pwm: to solve the bug :
[10:33:29:984]<4>[  127.237239] [<c07b5200>] (__mutex_lock_slowpath+0x1c0/0x22c) from [<c07b529c>] (mutex_lock+0x30/0x48)
[10:33:30:000]<4>[  127.237255] [<c07b529c>] (mutex_lock+0x30/0x48) from [<c057d32c>] (clk_prepare_lock+0x48/0xe0)
[10:33:30:015]<4>[  127.237269] [<c057d32c>] (clk_prepare_lock+0x48/0xe0) from [<c057eea4>] (clk_prepare+0xc/0x24)
[10:33:30:031]<4>[  127.237285] [<c057eea4>] (clk_prepare+0xc/0x24) from [<c0282df8>] (rk_pwm_config+0x20/0x74)
[10:33:30:031]<4>[  127.237300] [<c0282df8>] (rk_pwm_config+0x20/0x74) from [<c0281904>] (pwm_config+0x54/0x60)
[10:33:30:031]<4>[  127.237317] [<c0281904>] (pwm_config+0x54/0x60) from [<c02c0528>] (pwm_regulator_set_voltage+0xd0/0xf4)
---

diff --git a/drivers/pwm/pwm-rockchip.c b/drivers/pwm/pwm-rockchip.c
index a15b38d75b80..137b58ab230d 100644
--- a/drivers/pwm/pwm-rockchip.c
+++ b/drivers/pwm/pwm-rockchip.c
@@ -467,13 +467,13 @@ static int  rk_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
 	struct rk_pwm_chip *pc = to_rk_pwm_chip(chip);
 	int ret;
 	
-	ret = clk_prepare_enable(pc->clk);
+	ret = clk_enable(pc->clk);
 	if (ret)
 		return ret;
 
 	ret = pc->config(chip, pwm, duty_ns, period_ns);
-	
-	clk_disable_unprepare(pc->clk);
+
+	clk_disable(pc->clk);
 
 	return 0;
 }
@@ -482,7 +482,7 @@ static int rk_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm)
 	struct rk_pwm_chip *pc = to_rk_pwm_chip(chip);
 	int ret = 0;
 
-	ret = clk_prepare_enable(pc->clk);
+	ret = clk_enable(pc->clk);
 	if (ret)
 		return ret;
 
@@ -496,7 +496,7 @@ static void rk_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm)
 
 	pc->set_enable(chip, pwm,false);
 
-	clk_disable_unprepare(pc->clk);
+	clk_disable(pc->clk);
 
 }
 
@@ -587,6 +587,7 @@ static int rk_pwm_probe(struct platform_device *pdev)
 	pc->chip.base = -1;
 	pc->chip.npwm = NUM_PWM;
 	spin_lock_init(&pc->lock);
+	clk_prepare(pc->clk);
 
 	/* Following enables PWM chip, channels would still be enabled individually through their control register */
 	DBG("npwm = %d, of_pwm_ncells =%d \n", pc->chip.npwm,pc->chip.of_pwm_n_cells);