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mpc5200: reduce delays in i2c 

The previous code waited 1000us before checking i2c
status. Measurement shows i2c is usually ready in
under 50us. Change the polling interval to 15us,
loop 6,667 times to keep the polling timeout constant
at 100ms.
This commit is contained in:
Jon Smirl 2009-04-04 17:44:51 -04:00 committed by Wolfgang Denk
parent c0a14aedc3
commit 3c853f31d6
1 changed files with 3 additions and 3 deletions
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6
cpu/mpc5xxx/i2c.c
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@ -38,7 +38,7 @@ DECLARE_GLOBAL_DATA_PTR;
#error CONFIG_SYS_I2C_MODULE is not properly configured
#endif
#define I2C_TIMEOUT 100
#define I2C_TIMEOUT 6667
#define I2C_RETRIES 3
struct mpc5xxx_i2c_tap {
@ -94,7 +94,7 @@ static int wait_for_bb(void)
mpc_reg_out(&regs->mcr, 0, 0);
mpc_reg_out(&regs->mcr, I2C_EN, 0);
#endif
udelay(1000);
udelay(15);
status = mpc_reg_in(&regs->msr);
}
@ -109,7 +109,7 @@ static int wait_for_pin(int *status)
*status = mpc_reg_in(&regs->msr);
while (timeout-- && !(*status & I2C_IF)) {
udelay(1000);
udelay(15);
*status = mpc_reg_in(&regs->msr);
}