From: Grazvydas Ignotas <notasas@gmail.com>
Date: Mon, 16 Feb 2015 19:48:18 +0000 (+0200)
Subject: leds-twl4030-pwm, pandora_bl: fix a race between the two
X-Git-Tag: sz_173~55
X-Git-Url: https://git.openpandora.org/cgi-bin/gitweb.cgi?p=pandora-kernel.git;a=commitdiff_plain;h=071cd8e3b4013c8a5b4ed7ebade8752da5cb936a;hp=e2517977596b7faff87f410b1b254676a0941383

leds-twl4030-pwm, pandora_bl: fix a race between the two

Both were doing rmw at startup, so some bits were getting lost.
---

diff --git a/drivers/leds/leds-twl4030-pwm.c b/drivers/leds/leds-twl4030-pwm.c
index 705750e62e8c..f6d656ed414d 100644
--- a/drivers/leds/leds-twl4030-pwm.c
+++ b/drivers/leds/leds-twl4030-pwm.c
@@ -55,21 +55,6 @@ struct twl4030_pwmled {
 	struct work_struct work;
 };
 
-static int twl4030_clear_set(u8 mod_no, u8 clear, u8 set, u8 reg)
-{
-	u8 val = 0;
-	int ret;
-
-	ret = twl_i2c_read_u8(mod_no, &val, reg);
-	if (ret)
-		return ret;
-
-	val &= ~clear;
-	val |= set;
-
-	return twl_i2c_write_u8(mod_no, val, reg);
-}
-
 static void twl4030_enable_ledab(enum twl4030_led led, bool enable)
 {
 	u8 bits;
@@ -80,14 +65,14 @@ static void twl4030_enable_ledab(enum twl4030_led led, bool enable)
 		bits = LEDEN_LEDBON | LEDEN_LEDBPWM;
 
 	if (enable)
-		twl4030_clear_set(TWL4030_MODULE_LED, 0, bits, TWL4030_LED_LEDEN);
+		twl_i2c_rmw_u8(TWL4030_MODULE_LED, 0, bits, TWL4030_LED_LEDEN);
 	else
-		twl4030_clear_set(TWL4030_MODULE_LED, bits, 0, TWL4030_LED_LEDEN);
+		twl_i2c_rmw_u8(TWL4030_MODULE_LED, bits, 0, TWL4030_LED_LEDEN);
 }
 
 static void twl4030_enable_pwm01(enum twl4030_led led, bool enable)
 {
-	u8 r, enbit, clkbit;
+	u8 enbit, clkbit;
 
 	if (led == TWL4030_PWM0) {
 		enbit = GPBR1_PWM0_ENABLE;
@@ -97,22 +82,19 @@ static void twl4030_enable_pwm01(enum twl4030_led led, bool enable)
 		clkbit = GPBR1_PWM1_CLK_ENABLE;
 	}
 
-	twl_i2c_read_u8(TWL4030_MODULE_INTBR, &r, TWL_INTBR_GPBR1);
-
 	if (enable) {
 		/* first enable clock, then PWM out */
-		r &= ~enbit;
-		r |= clkbit;
-		twl_i2c_write_u8(TWL4030_MODULE_INTBR, r, TWL_INTBR_GPBR1);
-		r |= enbit;
+		twl_i2c_rmw_u8(TWL4030_MODULE_INTBR,
+			enbit, clkbit, TWL_INTBR_GPBR1);
+		twl_i2c_rmw_u8(TWL4030_MODULE_INTBR,
+			0, enbit, TWL_INTBR_GPBR1);
 	} else {
 		/* first disable PWM output, then clock */
-		r &= ~enbit;
-		twl_i2c_write_u8(TWL4030_MODULE_INTBR, r, TWL_INTBR_GPBR1);
-		r &= ~clkbit;
+		twl_i2c_rmw_u8(TWL4030_MODULE_INTBR,
+			enbit, 0, TWL_INTBR_GPBR1);
+		twl_i2c_rmw_u8(TWL4030_MODULE_INTBR,
+			clkbit, 0, TWL_INTBR_GPBR1);
 	}
-
-	twl_i2c_write_u8(TWL4030_MODULE_INTBR, r, TWL_INTBR_GPBR1);
 }
 
 static void twl4030_pwmled_work(struct work_struct *work)
@@ -189,18 +171,18 @@ static int __devinit twl4030_pwmled_probe(struct platform_device *pdev)
 			led->module = TWL4030_MODULE_PWM0;
 			led->enable = twl4030_enable_pwm01;
 			/* enable PWM0 in pin mux */
-			twl4030_clear_set(TWL4030_MODULE_INTBR,
+			twl_i2c_rmw_u8(TWL4030_MODULE_INTBR,
 				0x0c, 0x04, TWL_INTBR_PMBR1);
 			/* enable PWM clock for initial write */
-			twl4030_clear_set(TWL4030_MODULE_INTBR,
+			twl_i2c_rmw_u8(TWL4030_MODULE_INTBR,
 				0, GPBR1_PWM0_CLK_ENABLE, TWL_INTBR_GPBR1);
 			break;
 		case TWL4030_PWM1:
 			led->module = TWL4030_MODULE_PWM1;
 			led->enable = twl4030_enable_pwm01;
-			twl4030_clear_set(TWL4030_MODULE_INTBR,
+			twl_i2c_rmw_u8(TWL4030_MODULE_INTBR,
 				0, 0x30, TWL_INTBR_PMBR1);
-			twl4030_clear_set(TWL4030_MODULE_INTBR,
+			twl_i2c_rmw_u8(TWL4030_MODULE_INTBR,
 				0, GPBR1_PWM1_CLK_ENABLE, TWL_INTBR_GPBR1);
 			break;
 		default:
diff --git a/drivers/video/backlight/pandora_bl.c b/drivers/video/backlight/pandora_bl.c
index 4ec30748b447..1187c2c00000 100644
--- a/drivers/video/backlight/pandora_bl.c
+++ b/drivers/video/backlight/pandora_bl.c
@@ -40,7 +40,6 @@
 static int pandora_backlight_update_status(struct backlight_device *bl)
 {
 	int brightness = bl->props.brightness;
-	u8 r;
 
 	if (bl->props.power != FB_BLANK_UNBLANK)
 		brightness = 0;
@@ -57,12 +56,10 @@ static int pandora_backlight_update_status(struct backlight_device *bl)
 			goto done;
 
 		/* first disable PWM0 output, then clock */
-		twl_i2c_read_u8(TWL4030_MODULE_INTBR, &r, TWL_INTBR_GPBR1);
-		r &= ~PWM0_ENABLE;
-		twl_i2c_write_u8(TWL4030_MODULE_INTBR, r, TWL_INTBR_GPBR1);
-		r &= ~PWM0_CLK_ENABLE;
-		twl_i2c_write_u8(TWL4030_MODULE_INTBR, r, TWL_INTBR_GPBR1);
-
+		twl_i2c_rmw_u8(TWL4030_MODULE_INTBR, PWM0_ENABLE, 0,
+			TWL_INTBR_GPBR1);
+		twl_i2c_rmw_u8(TWL4030_MODULE_INTBR, PWM0_CLK_ENABLE, 0,
+			TWL_INTBR_GPBR1);
 		goto done;
 	}
 
@@ -75,12 +72,10 @@ static int pandora_backlight_update_status(struct backlight_device *bl)
 					TWL_PWM0_OFF);
 
 		/* first enable clock, then PWM0 out */
-		twl_i2c_read_u8(TWL4030_MODULE_INTBR, &r, TWL_INTBR_GPBR1);
-		r &= ~PWM0_ENABLE;
-		r |= PWM0_CLK_ENABLE;
-		twl_i2c_write_u8(TWL4030_MODULE_INTBR, r, TWL_INTBR_GPBR1);
-		r |= PWM0_ENABLE;
-		twl_i2c_write_u8(TWL4030_MODULE_INTBR, r, TWL_INTBR_GPBR1);
+		twl_i2c_rmw_u8(TWL4030_MODULE_INTBR,
+			PWM0_ENABLE, PWM0_CLK_ENABLE, TWL_INTBR_GPBR1);
+		twl_i2c_rmw_u8(TWL4030_MODULE_INTBR,
+			0, PWM0_ENABLE, TWL_INTBR_GPBR1);
 
 		/*
 		 * TI made it very easy to enable digital control, so easy that
@@ -117,7 +112,6 @@ static int pandora_backlight_probe(struct platform_device *pdev)
 {
 	struct backlight_properties props;
 	struct backlight_device *bl;
-	u8 r;
 
 	memset(&props, 0, sizeof(props));
 	props.max_brightness = MAX_USER_VALUE;
@@ -139,10 +133,8 @@ static int pandora_backlight_probe(struct platform_device *pdev)
 	backlight_update_status(bl);
 
 	/* enable PWM function in pin mux */
-	twl_i2c_read_u8(TWL4030_MODULE_INTBR, &r, TWL_INTBR_PMBR1);
-	r &= ~TWL_PMBR1_PWM0_MUXMASK;
-	r |= TWL_PMBR1_PWM0;
-	twl_i2c_write_u8(TWL4030_MODULE_INTBR, r, TWL_INTBR_PMBR1);
+	twl_i2c_rmw_u8(TWL4030_MODULE_INTBR,
+		TWL_PMBR1_PWM0_MUXMASK, TWL_PMBR1_PWM0, TWL_INTBR_PMBR1);
 
 	return 0;
 }