diff options
| -rw-r--r-- | chip/stm32/i2c-stm32f0.c | 78 | ||||
| -rw-r--r-- | include/i2c.h | 11 |
2 files changed, 58 insertions, 31 deletions
diff --git a/chip/stm32/i2c-stm32f0.c b/chip/stm32/i2c-stm32f0.c index 14b52770c8..860a0a8c14 100644 --- a/chip/stm32/i2c-stm32f0.c +++ b/chip/stm32/i2c-stm32f0.c @@ -68,42 +68,39 @@ static int wait_isr(int port, int mask) return EC_ERROR_TIMEOUT; } -#if defined(CONFIG_HOSTCMD_I2C_SLAVE_ADDR) && \ -defined(CONFIG_LOW_POWER_IDLE) && \ -(I2C_PORT_EC == STM32_I2C1_PORT) -/* 8MHz i2cclk register settings */ -#define STM32_I2C_TIMINGR_1000MHZ 0x00100306 -#define STM32_I2C_TIMINGR_400MHZ 0x00310309 -#define STM32_I2C_TIMINGR_100MHZ 0x10420f13 -#else -/* 48MHz i2cclk register settings */ -#define STM32_I2C_TIMINGR_1000MHZ 0x50100103 -#define STM32_I2C_TIMINGR_400MHZ 0x50330309 -#define STM32_I2C_TIMINGR_100MHZ 0xB0421214 -#endif - -static void i2c_set_freq_port(const struct i2c_port_t *p) +/* Supported i2c input clocks */ +enum stm32_i2c_clk_src { + I2C_CLK_SRC_48MHZ = 0, + I2C_CLK_SRC_8MHZ = 1, + I2C_CLK_SRC_COUNT, +}; + +/* timingr register values for supported input clks / i2c clk rates */ +static const uint32_t timingr_regs[I2C_CLK_SRC_COUNT][I2C_FREQ_COUNT] = { + [I2C_CLK_SRC_48MHZ] = { + [I2C_FREQ_1000KHZ] = 0x00100306, + [I2C_FREQ_400KHZ] = 0x00310309, + [I2C_FREQ_100KHZ] = 0x10420f13, + }, + [I2C_CLK_SRC_8MHZ] = { + [I2C_FREQ_1000KHZ] = 0x50100103, + [I2C_FREQ_400KHZ] = 0x50330309, + [I2C_FREQ_100KHZ] = 0xB0421214, + }, +}; + +static void i2c_set_freq_port(const struct i2c_port_t *p, + enum stm32_i2c_clk_src src, + enum i2c_freq freq) { int port = p->port; + const uint32_t *regs = timingr_regs[src]; /* Disable port */ STM32_I2C_CR1(port) = 0; STM32_I2C_CR2(port) = 0; /* Set clock frequency */ - switch (p->kbps) { - case 1000: - STM32_I2C_TIMINGR(port) = STM32_I2C_TIMINGR_1000MHZ; - break; - case 400: - STM32_I2C_TIMINGR(port) = STM32_I2C_TIMINGR_400MHZ; - break; - case 100: - STM32_I2C_TIMINGR(port) = STM32_I2C_TIMINGR_100MHZ; - break; - default: /* unknown speed, defaults to 100kBps */ - CPRINTS("I2C bad speed %d kBps", p->kbps); - STM32_I2C_TIMINGR(port) = STM32_I2C_TIMINGR_100MHZ; - } + STM32_I2C_TIMINGR(port) = regs[freq]; /* Enable port */ STM32_I2C_CR1(port) = STM32_I2C_CR1_PE; } @@ -116,12 +113,14 @@ static void i2c_set_freq_port(const struct i2c_port_t *p) static void i2c_init_port(const struct i2c_port_t *p) { int port = p->port; + enum stm32_i2c_clk_src src = I2C_CLK_SRC_48MHZ; + enum i2c_freq freq; /* Enable clocks to I2C modules if necessary */ if (!(STM32_RCC_APB1ENR & (1 << (21 + port)))) STM32_RCC_APB1ENR |= 1 << (21 + port); - if (port == 0) { + if (port == STM32_I2C1_PORT) { #if defined(CONFIG_HOSTCMD_I2C_SLAVE_ADDR) && \ defined(CONFIG_LOW_POWER_IDLE) && \ (I2C_PORT_EC == STM32_I2C1_PORT) @@ -131,6 +130,7 @@ defined(CONFIG_LOW_POWER_IDLE) && \ * upon exit from STOP mode. */ STM32_RCC_CFGR3 &= ~0x10; + src = I2C_CLK_SRC_8MHZ; #else /* Use SYSCLK for i2c clock. */ STM32_RCC_CFGR3 |= 0x10; @@ -140,8 +140,24 @@ defined(CONFIG_LOW_POWER_IDLE) && \ /* Configure GPIOs */ gpio_config_module(MODULE_I2C, 1); + /* Set clock frequency */ + switch (p->kbps) { + case 1000: + freq = I2C_FREQ_1000KHZ; + break; + case 400: + freq = I2C_FREQ_400KHZ; + break; + case 100: + freq = I2C_FREQ_100KHZ; + break; + default: /* unknown speed, defaults to 100kBps */ + CPRINTS("I2C bad speed %d kBps", p->kbps); + freq = I2C_FREQ_100KHZ; + } + /* Set up initial bus frequencies */ - i2c_set_freq_port(p); + i2c_set_freq_port(p, src, freq); } /*****************************************************************************/ diff --git a/include/i2c.h b/include/i2c.h index 674dd84e80..fdda5a0187 100644 --- a/include/i2c.h +++ b/include/i2c.h @@ -13,6 +13,17 @@ /* Flags for slave address field, in addition to the 8-bit address */ #define I2C_FLAG_BIG_ENDIAN 0x100 /* 16 byte values are MSB-first */ +/* + * Supported I2C CLK frequencies. + * TODO(crbug.com/549286): Use this enum in i2c_port_t. + */ +enum i2c_freq { + I2C_FREQ_1000KHZ = 0, + I2C_FREQ_400KHZ = 1, + I2C_FREQ_100KHZ = 2, + I2C_FREQ_COUNT, +}; + /* Data structure to define I2C port configuration. */ struct i2c_port_t { const char *name; /* Port name */ |