drm/i915: Tidy dvo_ch7017 and print out which chip we detect

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>

1 files changed, 27 insertions, 36 deletions

diff --git a/drivers/gpu/drm/i915/dvo_ch7017.c b/drivers/gpu/drm/i915/dvo_ch7017.c
index 0bc8ce1ad9aa..af70337567ce 100644
--- a/drivers/gpu/drm/i915/dvo_ch7017.c
+++ b/drivers/gpu/drm/i915/dvo_ch7017.c
@@ -165,56 +165,35 @@ struct ch7017_priv {
 static void ch7017_dump_regs(struct intel_dvo_device *dvo);
 static void ch7017_dpms(struct intel_dvo_device *dvo, int mode);
 
-static bool ch7017_read(struct intel_dvo_device *dvo, int addr, uint8_t *val)
+static bool ch7017_read(struct intel_dvo_device *dvo, u8 addr, u8 *val)
 {
-        struct i2c_adapter *adapter = dvo->i2c_bus;
-        u8 out_buf[2];
-        u8 in_buf[2];
-
         struct i2c_msg msgs[] = {
                 {
                         .addr = dvo->slave_addr,
                         .flags = 0,
                         .len = 1,
-                        .buf = out_buf,
+                        .buf = &addr,
                 },
                 {
                         .addr = dvo->slave_addr,
                         .flags = I2C_M_RD,
                         .len = 1,
-                        .buf = in_buf,
+                        .buf = val,
                 }
         };
-
-        out_buf[0] = addr;
-        out_buf[1] = 0;
-
-        if (i2c_transfer(adapter, msgs, 2) == 2) {
-                *val= in_buf[0];
-                return true;
-        };
-
-        return false;
+        return i2c_transfer(dvo->i2c_bus, msgs, 2) == 2;
 }
 
-static bool ch7017_write(struct intel_dvo_device *dvo, int addr, uint8_t val)
+static bool ch7017_write(struct intel_dvo_device *dvo, u8 addr, u8 val)
 {
-        struct i2c_adapter *adapter = dvo->i2c_bus;
-        uint8_t out_buf[2];
+        uint8_t buf[2] = { addr, val };
         struct i2c_msg msg = {
                 .addr = dvo->slave_addr,
                 .flags = 0,
                 .len = 2,
-                .buf = out_buf,
+                .buf = buf,
         };
-
-        out_buf[0] = addr;
-        out_buf[1] = val;
-
-        if (i2c_transfer(adapter, &msg, 1) == 1)
-                return true;
-
-        return false;
+        return i2c_transfer(dvo->i2c_bus, &msg, 1) == 1;
 }
 
 /** Probes for a CH7017 on the given bus and slave address. */
@@ -222,7 +201,8 @@ static bool ch7017_init(struct intel_dvo_device *dvo,
                         struct i2c_adapter *adapter)
 {
         struct ch7017_priv *priv;
-        uint8_t val;
+        const char *str;
+        u8 val;
 
         priv = kzalloc(sizeof(struct ch7017_priv), GFP_KERNEL);
         if (priv == NULL)
@@ -234,16 +214,27 @@ static bool ch7017_init(struct intel_dvo_device *dvo,
         if (!ch7017_read(dvo, CH7017_DEVICE_ID, &val))
                 goto fail;
 
-        if (val != CH7017_DEVICE_ID_VALUE &&
-            val != CH7018_DEVICE_ID_VALUE &&
-            val != CH7019_DEVICE_ID_VALUE) {
+        switch (val) {
+        case CH7017_DEVICE_ID_VALUE:
+                str = "ch7017";
+                break;
+        case CH7018_DEVICE_ID_VALUE:
+                str = "ch7018";
+                break;
+        case CH7019_DEVICE_ID_VALUE:
+                str = "ch7019";
+                break;
+        default:
                 DRM_DEBUG_KMS("ch701x not detected, got %d: from %s "
-                                "Slave %d.\n",
-                          val, adapter->name,dvo->slave_addr);
+                              "slave %d.\n",
+                              val, adapter->name,dvo->slave_addr);
                 goto fail;
         }
 
+        DRM_DEBUG_KMS("%s detected on %s, addr %d\n",
+                      str, adapter->name, dvo->slave_addr);
         return true;
+
 fail:
         kfree(priv);
         return false;
@@ -365,7 +356,7 @@ static void ch7017_dpms(struct intel_dvo_device *dvo, int mode)
         }
 
         /* XXX: Should actually wait for update power status somehow */
-        udelay(20000);
+        msleep(20);
 }
 
 static void ch7017_dump_regs(struct intel_dvo_device *dvo)