i2c: tegra: use readl_poll_timeout after config_load reg programmed
authorShardar Shariff Md <smohammed@nvidia.com>
Wed, 31 Aug 2016 13:28:40 +0000 (18:58 +0530)
committerWolfram Sang <wsa@the-dreams.de>
Thu, 8 Sep 2016 20:32:46 +0000 (22:32 +0200)
After CONFIG_LOAD register is programmed instead of explicitly waiting
for timeout, use readl_poll_timeout() to check for register value to get
updated or wait till timeout.

Signed-off-by: Shardar Shariff Md <smohammed@nvidia.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
drivers/i2c/busses/i2c-tegra.c

index d86a993..e93c72a 100644 (file)
@@ -30,6 +30,7 @@
 #include <linux/reset.h>
 #include <linux/pinctrl/consumer.h>
 #include <linux/pm_runtime.h>
+#include <linux/iopoll.h>
 
 #include <asm/unaligned.h>
 
 #define I2C_CLKEN_OVERRIDE                     0x090
 #define I2C_MST_CORE_CLKEN_OVR                 BIT(0)
 
+#define I2C_CONFIG_LOAD_TIMEOUT                        1000000
+
 /*
  * msg_end_type: The bus control which need to be send at end of transfer.
  * @MSG_END_STOP: Send stop pulse at end of transfer.
@@ -448,7 +451,6 @@ static int tegra_i2c_init(struct tegra_i2c_dev *i2c_dev)
        u32 val;
        int err;
        u32 clk_divisor;
-       unsigned long timeout = jiffies + HZ;
 
        err = pm_runtime_get_sync(i2c_dev->dev);
        if (err < 0) {
@@ -497,15 +499,18 @@ static int tegra_i2c_init(struct tegra_i2c_dev *i2c_dev)
                i2c_writel(i2c_dev, I2C_MST_CORE_CLKEN_OVR, I2C_CLKEN_OVERRIDE);
 
        if (i2c_dev->hw->has_config_load_reg) {
+               unsigned long reg_offset;
+               void __iomem *addr;
+
+               reg_offset = tegra_i2c_reg_addr(i2c_dev, I2C_CONFIG_LOAD);
+               addr = i2c_dev->base + reg_offset;
                i2c_writel(i2c_dev, I2C_MSTR_CONFIG_LOAD, I2C_CONFIG_LOAD);
-               while (i2c_readl(i2c_dev, I2C_CONFIG_LOAD) != 0) {
-                       if (time_after(jiffies, timeout)) {
-                               dev_warn(i2c_dev->dev,
-                                       "timeout waiting for config load\n");
-                               err = -ETIMEDOUT;
-                               goto err;
-                       }
-                       msleep(1);
+               err = readl_poll_timeout(addr, val, val == 0, 1000,
+                                        I2C_CONFIG_LOAD_TIMEOUT);
+               if (err) {
+                       dev_warn(i2c_dev->dev,
+                                "timeout waiting for config load\n");
+                       goto err;
                }
        }