[PATCH v7 2/4] i2c: tegra: calculate timeout for config load when needed

Shardar Shariff Md
2016-04-25T13:39:24Z

Instead of calculating timeout for the config load during init,
calculate it after config load register is written by using
readx_poll_timeout().

Signed-off-by: Shardar Shariff Md <smohammed@nvidia.com>

---
Changes in v4:
- Split timeout calculation to separate patch

Changes in v5:
- Move disabling of clock to separate patch
---
drivers/i2c/busses/i2c-tegra.c | 22 +++++++++++++---------
1 file changed, 13 insertions(+), 9 deletions(-)

diff --git a/drivers/i2c/busses/i2c-tegra.c b/drivers/i2c/busses/i2c-tegra.c
index 445398c3..c1b02c7 100644
--- a/drivers/i2c/busses/i2c-tegra.c
+++ b/drivers/i2c/busses/i2c-tegra.c
@@ -28,6 +28,7 @@
#include <linux/of_device.h>
#include <linux/module.h>
#include <linux/reset.h>
+#include <linux/iopoll.h>

#include <asm/unaligned.h>

@@ -110,6 +111,8 @@
#define I2C_CLKEN_OVERRIDE 0x090
#define I2C_MST_CORE_CLKEN_OVR (1 << 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.
@@ -428,7 +431,6 @@ static int tegra_i2c_init(struct tegra_i2c_dev *i2c_dev)
u32 val;
int err = 0;
u32 clk_divisor;
- unsigned long timeout = jiffies + HZ;

err = tegra_i2c_clock_enable(i2c_dev);
if (err < 0) {
@@ -478,15 +480,17 @@ 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) {
+ u32 val;
+
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 = readx_poll_timeout(readl, i2c_dev->base +
+ tegra_i2c_reg_addr(i2c_dev,
+ I2C_CONFIG_LOAD), val, val == 0,
+ 1000, I2C_CONFIG_LOAD_TIMEOUT);
+ if (err) {
+ dev_warn(i2c_dev->dev,
+ "timeout waiting for config load\n");
+ goto err;
}
}

--
1.8.1.5