leds-lm3530: set the max_brightness to 127
authorKim, Milo <Milo.Kim@ti.com>
Fri, 23 Mar 2012 22:02:11 +0000 (15:02 -0700)
committerLinus Torvalds <torvalds@linux-foundation.org>
Fri, 23 Mar 2012 23:58:35 +0000 (16:58 -0700)
Only 7 bits are used for updating the brightness.  (register address :
A0h) So the max_brightness property of lm3530 should be set to 127.

On initializing registers, maximum initial brightness is limited to
'max_brightness'.

Division-by-two is removed on updating the brightness.  This arithmetic is
not necessary because the range of brightness is 0 ~ 127= .

Signed-off-by: Milo(Woogyom) Kim <milo.kim@ti.com>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
drivers/leds/leds-lm3530.c

index e59c166a0ce2261dd2515930ff297c1b57b5d25a..2c32a8c45f89d5002c93e1357307643ba899018b 100644 (file)
@@ -80,6 +80,9 @@
 #define LM3530_DEF_ZT_3                        (0x33)
 #define LM3530_DEF_ZT_4                        (0x19)
 
+/* 7 bits are used for the brightness : LM3530_BRT_CTRL_REG */
+#define MAX_BRIGHTNESS                 (127)
+
 struct lm3530_mode_map {
        const char *mode;
        enum lm3530_mode mode_val;
@@ -207,6 +210,9 @@ static int lm3530_init_registers(struct lm3530_data *drvdata)
        else
                brightness = drvdata->brightness = pltfm->brt_val;
 
+       if (brightness > drvdata->led_dev.max_brightness)
+               brightness = drvdata->led_dev.max_brightness;
+
        reg_val[0] = gen_config;        /* LM3530_GEN_CONFIG */
        reg_val[1] = als_config;        /* LM3530_ALS_CONFIG */
        reg_val[2] = brt_ramp;          /* LM3530_BRT_RAMP_RATE */
@@ -264,12 +270,12 @@ static void lm3530_brightness_set(struct led_classdev *led_cdev,
 
                /* set the brightness in brightness control register*/
                err = i2c_smbus_write_byte_data(drvdata->client,
-                               LM3530_BRT_CTRL_REG, brt_val / 2);
+                               LM3530_BRT_CTRL_REG, brt_val);
                if (err)
                        dev_err(&drvdata->client->dev,
                                "Unable to set brightness: %d\n", err);
                else
-                       drvdata->brightness = brt_val / 2;
+                       drvdata->brightness = brt_val;
 
                if (brt_val == 0) {
                        err = regulator_disable(drvdata->regulator);
@@ -380,6 +386,7 @@ static int __devinit lm3530_probe(struct i2c_client *client,
        drvdata->enable = false;
        drvdata->led_dev.name = LM3530_LED_DEV;
        drvdata->led_dev.brightness_set = lm3530_brightness_set;
+       drvdata->led_dev.max_brightness = MAX_BRIGHTNESS;
 
        i2c_set_clientdata(client, drvdata);