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Tiva I2C: For TM4C, high speed mode is now configurable (but disabled as EXPERIMENTAL)

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This commit is contained in:
Gregory Nutt 2015-01-06 10:48:08 -06:00
parent 207835bd0d
commit 6f8125bf61
3 changed files with 24 additions and 4 deletions
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8
arch/arm/src/tiva/Kconfig
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@ -634,6 +634,14 @@ config TIVA_I2C_TIMEOTICKS
endif # !TIVA_I2C_DYNTIMEO
config TIVA_I2C_HIGHSPEED
bool "High speed support"
default n
depends on ARCH_CHIP_TM4C && EXPERIMENTAL
---help---
Enable support for high speed I2C transfers.
Only partially implemented and completely untested.
config TIVA_I2C_REGDEBUG
bool "Register level debug"
default n

2
arch/arm/src/tiva/chip/tiva_i2c.h
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@ -62,7 +62,7 @@
#if defined(CONFIG_ARCH_CHIP_TM4C)
# define TIVA_I2CM_CLKOCNT_OFFSET 0x0024 /* I2C Master Clock Low Timeout Count */
# define TIVA_I2CM_BMON_OFFSET 0x002c /* I2C Master Configuration */
# define TIVA_I2CM_BMON_OFFSET 0x002c /* I2C Master Bus Monitor */
#endif
#if defined(CONFIG_ARCH_CHIP_TM4C129)

18
arch/arm/src/tiva/tiva_i2c.c
View File

@ -1783,6 +1783,18 @@ static int tiva_i2c_initialize(struct tiva_i2c_priv_s *priv, uint32_t frequency)
regval |= I2CM_CR_MFE;
tiva_i2c_putreg(priv, TIVA_I2CM_CR_OFFSET, regval);
#ifdef TIVA_I2CSC_PC_OFFSET
#ifdef CONFIG_TIVA_I2C_HIGHSPEED
/* Enable high-speed mode */
tiva_i2c_putreg(priv, TIVA_I2CSC_PC_OFFSET, I2CSC_PC_HS);
#else
/* Disable high-speed mode */
tiva_i2c_putreg(priv, TIVA_I2CSC_PC_OFFSET, 0);
#endif
#endif
/* Configure the the initial I2C clock frequency. */
(void)tiva_i2c_setclock(priv, frequency);
@ -1867,13 +1879,13 @@ static uint32_t tiva_i2c_setclock(struct tiva_i2c_priv_s *priv, uint32_t frequen
DEBUGASSERT((regval & I2CM_TPR_MASK) == regval);
tiva_i2c_putreg(priv, TIVA_I2CM_TPR_OFFSET, regval);
#ifdef TIVA_I2CSC_PP_OFFSET
#if defined(CONFIG_TIVA_I2C_HIGHSPEED) && defined(TIVA_I2CSC_PC_OFFSET)
/* If the I2C peripheral is High-Speed enabled then choose the highest
* speed that is less than or equal to 3.4 Mbps.
*/
regval = tiva_i2c_getreg(priv, TIVA_I2CSC_PP_OFFSET);
if ((regval & I2CSC_PP_HS) != 0)
regval = tiva_i2c_getreg(priv, TIVA_I2CSC_PC_OFFSET);
if ((regval & I2CSC_PC_HS) != 0)
{
tmp = (2 * 3 * 3400000);
regval = (((SYSCLK_FREQUENCY + tmp - 1) / tmp) - 1) << I2CM_TPR_SHIFT;