i2c: lp5521: simplify mode setting

Avoid using string magic and use integer for comparisson

Signed-off-by: Felipe Balbi <felipe.balbi@nokia.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>

diff --git a/drivers/i2c/chips/lp5521.c b/drivers/i2c/chips/lp5521.c
index e040c4d90856eac3a27a4383881bb59366fa2505..9e94ff8b52924e92d744236080f2bed013f46271 100644 (file)
--- a/drivers/i2c/chips/lp5521.c
+++ b/drivers/i2c/chips/lp5521.c
@@ -46,10 +46,6 @@
 #define LP5521_REG_G_PROG_MEM          0x30
 #define LP5521_REG_B_PROG_MEM          0x50
 
-#define LP5521_MODE_LOAD               "load"
-#define LP5521_MODE_RUN                        "run"
-#define LP5521_MODE_DIRECT_CONTROL     "direct"
-
 #define LP5521_CURRENT_1m5             0x0f
 #define LP5521_CURRENT_3m1             0x1f
 #define LP5521_CURRENT_4m7             0x2f
@@ -69,17 +65,23 @@
 
 #define LP5521_PROGRAM_LENGTH          32      /* in bytes */
 
+enum lp5521_mode {
+       LP5521_MODE_LOAD,
+       LP5521_MODE_RUN,
+       LP5521_MODE_DIRECT_CONTROL,
+};
+
 struct lp5521_chip {
        /* device lock */
        struct mutex            lock;
        struct i2c_client       *client;
-       char                    *mode;
+       enum lp5521_mode        mode;
        int                     red;
        int                     green;
        int                     blue;
 };
 
-static int lp5521_set_mode(struct lp5521_chip *chip, char *mode);
+static int lp5521_set_mode(struct lp5521_chip *chip, enum lp5521_mode mode);
 
 static inline int lp5521_write(struct i2c_client *client, u8 reg, u8 value)
 {
@@ -313,8 +315,25 @@ static ssize_t show_mode(struct device *dev,
                char *buf)
 {
        struct lp5521_chip *chip = dev_get_drvdata(dev);
+       char *mode;
+
+       mutex_lock(&chip->lock);
+       switch (chip->mode) {
+       case LP5521_MODE_RUN:
+               mode = "run";
+               break;
+       case LP5521_MODE_LOAD:
+               mode = "load";
+               break;
+       case LP5521_MODE_DIRECT_CONTROL:
+               mode = "direct";
+               break;
+       default:
+               mode = "undefined";
+       }
+       mutex_unlock(&chip->lock);
 
-       return sprintf(buf, "%s\n", chip->mode);
+       return sprintf(buf, "%s\n", mode);
 }
 
 static ssize_t store_mode(struct device *dev,
@@ -442,23 +461,28 @@ static void lp5521_unregister_sysfs(struct i2c_client *client)
 /*                     Set chip operating mode                 */
 /*--------------------------------------------------------------*/
 
-static int lp5521_set_mode(struct lp5521_chip *chip, char *mode)
+static int lp5521_set_mode(struct lp5521_chip *chip, enum lp5521_mode mode)
 {
        struct i2c_client *client = chip->client ;
        int ret = 0;
 
        /* if in that mode already do nothing, except for run */
-       if (!strcmp(mode, chip->mode) && strcmp(mode, LP5521_MODE_RUN))
+       if (chip->mode == mode && mode != LP5521_MODE_RUN)
                return 0;
 
-       if (!strcmp(mode, LP5521_MODE_RUN))
+       switch (mode) {
+       case LP5521_MODE_RUN:
                ret = lp5521_run_program(chip);
-
-       if (!strcmp(mode, LP5521_MODE_LOAD))
+               break;
+       case LP5521_MODE_LOAD:
                ret |= lp5521_write(client, LP5521_REG_OP_MODE, 0x15);
-
-       if (!strcmp(mode, LP5521_MODE_DIRECT_CONTROL))
+               break;
+       case LP5521_MODE_DIRECT_CONTROL:
                ret |= lp5521_write(client, LP5521_REG_OP_MODE, 0x3F);
+               break;
+       default:
+               dev_dbg(&client->dev, "unsupported mode %d\n", mode);
+       }
 
        chip->mode = mode;