media: video: tegra: optimize writing gain register in ar0832

It used to set the same gain to four different registers
of each color component. Setting gain to global gain
register is equivalent to setting four registers.
This will save time to set gain.

Bug 889717

Reviewed-on: http://git-master/r/59443
(cherry picked from commit 618ebc7c8eda03fac467660520c9ad17043e467c)

Change-Id: Id58542c69c5c55befe8e045df0488770377bc126
Reviewed-on: http://git-master/r/59964
Reviewed-by: Varun Colbert <vcolbert@nvidia.com>
Tested-by: Varun Colbert <vcolbert@nvidia.com>
Rebase-Id: Re463dd7b1c73428aa3fc77fbd40645176a2e4220

diff --git a/drivers/media/video/tegra/ar0832_main.c b/drivers/media/video/tegra/ar0832_main.c
index 7cbed7c100942f48c75f84ca26a91400550c2275..aede4993140b22979efaaa2a28e7b6105558138f 100644 (file)
--- a/drivers/media/video/tegra/ar0832_main.c
+++ b/drivers/media/video/tegra/ar0832_main.c
@@ -68,6 +68,7 @@ static u16 DefaultImageHeight =  680;
 
 #define AR0832_RESET_REG       0x301A
 #define AR0832_ID_REG          0x31FC
+#define AR0832_GLOBAL_GAIN     0x305E
 
 /* AR0832_RESET_REG */
 #define AR0832_RESET_REG_GROUPED_PARAMETER_HOLD                (1 << 15)
@@ -844,16 +845,11 @@ static inline void ar0832_get_focuser_data_regs(struct ar0832_reg *regs,
        regs->val = (value) & 0xFFFF;
 }
 
-static inline void ar0832_get_gain_reg(struct ar0832_reg *regs, u16 gain)
+static inline void ar0832_set_gain_reg(struct ar0832_reg *regs, u16 gain)
 {
-       regs->addr = 0x3056;
+       /* global_gain register*/
+       regs->addr = AR0832_GLOBAL_GAIN;
        regs->val = gain;
-       (regs + 1)->addr = 0x3058;
-       (regs + 1)->val = gain;
-       (regs + 2)->addr = 0x305A;
-       (regs + 2)->val = gain;
-       (regs + 3)->addr = 0x305C;
-       (regs + 3)->val = gain;
 }
 
 static int ar0832_write_reg8(struct i2c_client *client, u16 addr, u8 val)
@@ -1042,22 +1038,21 @@ static int ar0832_set_coarse_time(struct ar0832_dev *dev,
        return 0;
 }
 
-static int ar0832_set_gain(struct ar0832_dev *dev, __u16 gain)
+static int ar0832_set_gain(struct ar0832_dev *dev, u16 gain)
 {
        int i;
        int ret = 0;
-       struct ar0832_reg reg_list_gain[4];
+       struct ar0832_reg reg_list_gain;
 
-       ret |= ar0832_write_reg8(dev->i2c_client, 0x0104, 0x1);
+       ret = ar0832_write_reg8(dev->i2c_client, 0x0104, 0x1);
        /* Gain Registers Start */
-       ar0832_get_gain_reg(reg_list_gain, gain);
-       for (i = 0; i < 4; i++) {
-               ret = ar0832_write_reg16(dev->i2c_client,
-                                       reg_list_gain[i].addr,
-                                       reg_list_gain[i].val);
-               if (ret)
-                       return ret;
-       }
+       ar0832_set_gain_reg(&reg_list_gain, gain);
+       ret |= ar0832_write_reg16(dev->i2c_client,
+                               reg_list_gain.addr,
+                               reg_list_gain.val);
+       if (ret)
+               return ret;
+
        /* Gain register End */
        ret |= ar0832_write_reg8(dev->i2c_client, 0x0104, 0x0);