From ad8557379602c34775a573758c9b222723af0b60 Mon Sep 17 00:00:00 2001 From: asterix Date: Fri, 30 Jul 2010 10:28:47 +0000 Subject: [PATCH] Add support for i2c bitbang. git-svn-id: https://src.develer.com/svnoss/bertos/branches/i2c@4091 38d2e660-2303-0410-9eaa-f027e97ec537 --- bertos/drv/i2c.h | 26 +++++- bertos/drv/i2c_bitbang.c | 172 +++++++++++++++++++++++-------------- bertos/hw/hw_i2c_bitbang.h | 62 +++++++++++++ 3 files changed, 196 insertions(+), 64 deletions(-) diff --git a/bertos/drv/i2c.h b/bertos/drv/i2c.h index c7fa9587..661c87f2 100644 --- a/bertos/drv/i2c.h +++ b/bertos/drv/i2c.h @@ -134,6 +134,25 @@ bool i2c_recv(void *_buf, size_t count); * I2c new api */ +/** + * \name I2C bitbang devices enum + */ +enum +{ + I2C_BITBANG0 = 1000, + I2C_BITBANG1, + I2C_BITBANG2, + I2C_BITBANG3, + I2C_BITBANG4, + I2C_BITBANG5, + I2C_BITBANG6, + I2C_BITBANG7, + I2C_BITBANG8, + I2C_BITBANG9, + + I2C_BITBANG_CNT /**< Number of serial ports */ +}; + /* * I2C error flags */ @@ -190,6 +209,7 @@ typedef struct I2c * Low level i2c init implementation prototype. */ void i2c_hw_init(I2c *i2c, int dev, uint32_t clock); +void i2c_hw_bitbangInit(I2c *i2c, int dev); void i2c_genericWrite(I2c *i2c, const void *_buf, size_t count); void i2c_genericRead(I2c *i2c, void *_buf, size_t count); @@ -303,7 +323,11 @@ INLINE int i2c_error(I2c *i2c) INLINE void i2c_init_3(I2c *i2c, int dev, uint32_t clock) { - i2c_hw_init(i2c, dev, clock); + if (dev > I2C_BITBANG0) + i2c_hw_bitbangInit(i2c, dev); + else + i2c_hw_init(i2c, dev, clock); + } #endif diff --git a/bertos/drv/i2c_bitbang.c b/bertos/drv/i2c_bitbang.c index 45847c93..2cf0e573 100644 --- a/bertos/drv/i2c_bitbang.c +++ b/bertos/drv/i2c_bitbang.c @@ -33,9 +33,11 @@ * \brief I2C bitbang driver (implementation) * * \author Francesco Sacchi + * \author Daniele Basile */ -#include "i2c.h" +#include "hw/hw_i2c_bitbang.h" + #include "cfg/cfg_i2c.h" #define LOG_LEVEL I2C_LOG_LEVEL @@ -46,9 +48,12 @@ #include #include +#include + #include -#include "hw/hw_i2c_bitbang.h" +#include + INLINE bool i2c_bitbang_start(void) { @@ -181,106 +186,85 @@ void i2c_bitbang_init(void) /* * New I2C API */ +#define I2C_DEV(i2c) ((int)((i2c)->hw)) -static void i2c_bitbang_stop(struct I2c *i2c) +static void i2c_bitbang_stop_1(struct I2c *i2c) { - SDA_LO; - SCL_HI; - I2C_HALFBIT_DELAY(); - SDA_HI; + i2c_hw_sdaLo(I2C_DEV(i2c)); + i2c_hw_sclHi(I2C_DEV(i2c)); + i2c_hw_halfbitDelay(I2C_DEV(i2c)); + i2c_hw_sdaHi(I2C_DEV(i2c)); } - -void i2c_bitbang_start(struct I2c *i2c, uint16_t slave_addr) +INLINE bool i2c_bitbang_start_1(struct I2c *i2c) { - if (i2c->flags & I2C_START_R) - slave_addr |= I2C_READBIT; - else - slave_addr &= ~I2C_READBIT; + i2c_hw_sdaHi(I2C_DEV(i2c)); + i2c_hw_sclHi(I2C_DEV(i2c)); + i2c_hw_halfbitDelay(I2C_DEV(i2c)); + i2c_hw_sdaLo(I2C_DEV(i2c)); + i2c_hw_halfbitDelay(I2C_DEV(i2c)); - /* - * Loop on the select write sequence: when the device is busy - * writing previously sent data it will reply to the SLA_W - * control byte with a NACK. In this case, we must - * keep trying until the deveice responds with an ACK. - */ - ticks_t start = timer_clock(); - while (i2c_bitbang_start()) - { - if (i2c_bitbang_put(slave_addr)) - return; - else if (timer_clock() - start > ms_to_ticks(CONFIG_I2C_START_TIMEOUT)) - { - LOG_ERR("Timeout on I2C start\n"); - i2c->errors |= I2C_START_TIMEOUT; - i2c_bitbang_stop(i2c); - return; - } - } - - LOG_ERR("START arbitration lost\n"); - i2c->errors |= I2C_ARB_LOST; - i2c_bitbang_stop(i2c); - return; + return !i2c_hw_sdaIn(I2C_DEV(i2c)); } -uint8_t i2c_bitbang_get(struct I2c *i2c) + +static uint8_t i2c_bitbang_getc(struct I2c *i2c) { uint8_t data = 0; for (uint8_t i = 0x80; i != 0; i >>= 1) { - SCL_LO; - I2C_HALFBIT_DELAY(); - SCL_HI; - if (SDA_IN) + i2c_hw_sclLo(I2C_DEV(i2c)); + i2c_hw_halfbitDelay(I2C_DEV(i2c)); + i2c_hw_sclHi(I2C_DEV(i2c)); + if (i2c_hw_sdaIn(I2C_DEV(i2c))) data |= i; else data &= ~i; - I2C_HALFBIT_DELAY(); + i2c_hw_halfbitDelay(I2C_DEV(i2c)); } - SCL_LO; + i2c_hw_sclLo(I2C_DEV(i2c)); /* Generate ACK/NACK */ if (i2c->xfer_size > 1) - SDA_LO; + i2c_hw_sdaLo(I2C_DEV(i2c)); else - SDA_HI; + i2c_hw_sdaHi(I2C_DEV(i2c)); - I2C_HALFBIT_DELAY(); - SCL_HI; - I2C_HALFBIT_DELAY(); - SCL_LO; - SDA_HI; + i2c_hw_halfbitDelay(I2C_DEV(i2c)); + i2c_hw_sclHi(I2C_DEV(i2c)); + i2c_hw_halfbitDelay(I2C_DEV(i2c)); + i2c_hw_sclLo(I2C_DEV(i2c)); + i2c_hw_sdaHi(I2C_DEV(i2c)); /* Generate stop condition (if requested) */ if ((i2c->xfer_size == 1) && (i2c->flags & I2C_STOP)) - i2c_bitbang_stop(i2c); + i2c_bitbang_stop_1(i2c); return data; } -void i2c_bitbang_put(struct I2c *i2c, uint8_t _data) +static void i2c_bitbang_putc(struct I2c *i2c, uint8_t _data) { /* Add ACK bit */ uint16_t data = (_data << 1) | 1; for (uint16_t i = 0x100; i != 0; i >>= 1) { - SCL_LO; + i2c_hw_sclLo(I2C_DEV(i2c)); if (data & i) - SDA_HI; + i2c_hw_sdaHi(I2C_DEV(i2c)); else - SDA_LO; - I2C_HALFBIT_DELAY(); + i2c_hw_sdaLo(I2C_DEV(i2c)); + i2c_hw_halfbitDelay(I2C_DEV(i2c)); - SCL_HI; - I2C_HALFBIT_DELAY(); + i2c_hw_sclHi(I2C_DEV(i2c)); + i2c_hw_halfbitDelay(I2C_DEV(i2c)); } - bool ack = !SDA_IN; - SCL_LO; - I2C_HALFBIT_DELAY(); + bool ack = !i2c_hw_sdaIn(I2C_DEV(i2c)); + i2c_hw_sclLo(I2C_DEV(i2c)); + i2c_hw_halfbitDelay(I2C_DEV(i2c)); if (!ack) { @@ -290,5 +274,67 @@ void i2c_bitbang_put(struct I2c *i2c, uint8_t _data) /* Generate stop condition (if requested) */ if (((i2c->xfer_size == 1) && (i2c->flags & I2C_STOP)) || i2c->errors) - i2c_bitbang_stop(i2c); + i2c_bitbang_stop_1(i2c); +} + + +static void i2c_bitbang_start_2(struct I2c *i2c, uint16_t slave_addr) +{ + if (i2c->flags & I2C_START_R) + slave_addr |= I2C_READBIT; + else + slave_addr &= ~I2C_READBIT; + + /* + * Loop on the select write sequence: when the device is busy + * writing previously sent data it will reply to the SLA_W + * control byte with a NACK. In this case, we must + * keep trying until the deveice responds with an ACK. + */ + ticks_t start = timer_clock(); + while (i2c_bitbang_start_1(i2c)) + { + i2c_bitbang_putc(i2c, slave_addr); + + if (!(i2c->errors & I2C_NO_ACK)) + return; + else if (timer_clock() - start > ms_to_ticks(CONFIG_I2C_START_TIMEOUT)) + { + LOG_ERR("Timeout on I2C start\n"); + i2c->errors |= I2C_START_TIMEOUT; + i2c_bitbang_stop_1(i2c); + return; + } + } + + LOG_ERR("START arbitration lost\n"); + i2c->errors |= I2C_ARB_LOST; + i2c_bitbang_stop_1(i2c); + return; } + + +static const I2cVT i2c_bitbang_vt = +{ + .start = i2c_bitbang_start_2, + .getc = i2c_bitbang_getc, + .putc = i2c_bitbang_putc, + .write = i2c_genericWrite, + .read = i2c_genericRead, +}; + + +/** + * Initialize i2c module. + */ +void i2c_hw_bitbangInit(I2c *i2c, int dev) +{ + MOD_CHECK(timer); + i2c->hw = (struct I2cHardware *)(dev - I2C_BITBANG0); + i2c->vt = &i2c_bitbang_vt; + + i2c_hw_bitbang_init(I2C_DEV(i2c)); + i2c_hw_sdaHi(I2C_DEV(i2c)); + i2c_hw_sclHi(I2C_DEV(i2c)); +} + diff --git a/bertos/hw/hw_i2c_bitbang.h b/bertos/hw/hw_i2c_bitbang.h index 8f3fbf5e..626cf7d8 100644 --- a/bertos/hw/hw_i2c_bitbang.h +++ b/bertos/hw/hw_i2c_bitbang.h @@ -62,4 +62,66 @@ */ #define I2C_HALFBIT_DELAY() do { /* Implement me! */ } while (0) + +/* + * New api + */ +#include + +INLINE void i2c_hw_sdaHi(int dev) +{ + (void)(dev); + /* Implement me:Set SDA High by setting SDA pin as input */ +} + +INLINE void i2c_hw_sdaLo(int dev) +{ + (void)(dev); + /* Implement me:Set SDA Low by setting SDA pin as open collector output */ +} + +INLINE void i2c_hw_sclHi(int dev) +{ + (void)(dev); + /* Implement me:Set SCL High by setting SCL pin as input */ +} + +INLINE void i2c_hw_sclLo(int dev) +{ + (void)(dev); + /* Implement me:Set SCL Low by setting SCL pin as open collector output */ +} + +INLINE bool i2c_hw_sdaIn(int dev) +{ + (void)(dev); + /* Implement me: read SDA pin state */ + return true; +} + +INLINE bool i2c_hw_sclIn(int dev) +{ + (void)(dev); + /* Implement me: read SCL pin state */ + return true; +} + +/** + * Half bit delay routine used to generate the correct timings. + */ +INLINE void i2c_hw_halfbitDelay(int dev) +{ + (void)(dev); + /* Implement me! */ +} + +/** + * This macro should set SDA and SCL lines as input. + */ +INLINE void i2c_hw_bitbang_init(int dev) +{ + (void)(dev); + /* Implement me! */ +} + #endif /* HW_I2C_BITBANG_H */ -- 2.25.1