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platform: x86: intel_scu_ipc: Replace mdelay with usleep_range in intel_scu_ipc_i2c_cntrl 

intel_scu_ipc_i2c_cntrl() calls mutex_lock(), which indicates
this function is not called in atomic context.

Despite never getting called from atomic context,
intel_scu_ipc_i2c_cntrl() calls mdelay to busily wait.
This is not necessary and can be replaced with usleep_range to
avoid busy waiting.

This is found by a static analysis tool named DCNS written by myself.
And I also manually check it.

Signed-off-by: Jia-Ju Bai <baijiaju1990@gmail.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
This commit is contained in:
Jia-Ju Bai 2018-04-10 20:57:56 +08:00 committed by Andy Shevchenko
parent de15b94f87
commit 8fddfb39a4
1 changed files with 2 additions and 2 deletions
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4
drivers/platform/x86/intel_scu_ipc.c
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@ -584,11 +584,11 @@ int intel_scu_ipc_i2c_cntrl(u32 addr, u32 *data)
if (cmd == IPC_I2C_READ) {
writel(addr, scu->i2c_base + IPC_I2C_CNTRL_ADDR);
/* Write not getting updated without delay */
mdelay(1);
usleep_range(1000, 2000);
*data = readl(scu->i2c_base + I2C_DATA_ADDR);
} else if (cmd == IPC_I2C_WRITE) {
writel(*data, scu->i2c_base + I2C_DATA_ADDR);
mdelay(1);
usleep_range(1000, 2000);
writel(addr, scu->i2c_base + IPC_I2C_CNTRL_ADDR);
} else {
dev_err(scu->dev,