From 226fef1618dd9a37c050bb79a24c77396cd14c46 Mon Sep 17 00:00:00 2001
From: jaseg <git@jaseg.net>
Date: Sun, 11 Oct 2020 23:31:12 +0200
Subject: Initial fw commit

---
 fw/i2c.h | 107 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 107 insertions(+)
 create mode 100644 fw/i2c.h

(limited to 'fw/i2c.h')

diff --git a/fw/i2c.h b/fw/i2c.h
new file mode 100644
index 0000000..d0c7ec6
--- /dev/null
+++ b/fw/i2c.h
@@ -0,0 +1,107 @@
+#ifndef __I2C_H
+#define __I2C_H
+
+#include "global.h"
+
+// Definitions of I2C analog filter state
+#define I2C_AF_ENABLE          ((uint32_t)0x00000000U) // Analog filter is enabled
+#define I2C_AF_DISABLE         I2C_CR1_ANFOFF          // Analog filter is disabled
+
+// Flags definitions for transmit function
+#define I2C_TX_STOP            ((uint32_t)0x00000000U) // Generate STOP condition
+#define I2C_TX_NOSTOP          ((uint32_t)0x10000000U) // Don't generate STOP condition
+#define I2C_TX_NOSTART         ((uint32_t)0x20000000U) // Don't generate START condition
+#define I2C_TX_CONT            ((uint32_t)0x40000000U) // The transmission will be continued
+// Definitions for compatibility with old code using this library
+#define I2C_GENSTOP_YES        I2C_TX_STOP
+#define I2C_GENSTOP_NO         I2C_TX_NOSTOP
+
+// Definition of bits to reset in CR2 register
+#define I2C_CR2_ALL            (I2C_CR2_SADD    | \
+								I2C_CR2_NBYTES  | \
+								I2C_CR2_RELOAD  | \
+								I2C_CR2_AUTOEND | \
+								I2C_CR2_RD_WRN  | \
+								I2C_CR2_START   | \
+								I2C_CR2_STOP)
+
+// Definition of all bits in ICR register (clear all I2C flags at once)
+#define I2C_ICR_ALL            (I2C_ICR_ADDRCF  | \
+								I2C_ICR_ALERTCF | \
+								I2C_ICR_ARLOCF  | \
+								I2C_ICR_BERRCF  | \
+								I2C_ICR_NACKCF  | \
+								I2C_ICR_OVRCF   | \
+								I2C_ICR_PECCF   | \
+								I2C_ICR_STOPCF  | \
+								I2C_ICR_TIMOUTCF)
+
+
+// Result of I2C functions
+typedef enum {
+	I2C_ERROR   = 0,
+	I2C_SUCCESS = !I2C_ERROR
+} i2cstatus;
+
+
+// Public functions and macros
+
+// Enable I2C peripheral
+// input:
+//   I2Cx - pointer to the I2C peripheral (I2C1, etc.)
+static inline void i2c_enable(I2C_TypeDef* I2Cx) {
+	I2Cx->CR1 |= I2C_CR1_PE;
+}
+
+// Disable I2C peripheral
+// input:
+//   I2Cx - pointer to the I2C peripheral (I2C1, etc.)
+static inline void i2c_disable(I2C_TypeDef* I2Cx) {
+	I2Cx->CR1 &= ~I2C_CR1_PE;
+}
+
+// Configure I2C noise filters
+// input:
+//   I2Cx - pointer to the I2C peripheral (I2C1, etc.)
+//   af - analog filter state, I2C_AF_DISABLE or I2C_AF_ENABLE
+//   df - digital filter configuration, can be a value in range from 0 to 15
+//        zero value means the digital filter is disabled
+//        this values means filtering capability up to (df * ti2cclk)
+// note: must be called only when I2C is disabled (PE bit in I2C_CR1 register is reset)
+static inline void i2c_config_filters(I2C_TypeDef* I2Cx, uint32_t af, uint32_t df) {
+	I2Cx->CR1 &= ~(I2C_CR1_ANFOFF | I2C_CR1_DNF);
+	I2Cx->CR1 |= (af & I2C_CR1_ANFOFF) | ((df << I2C_CR1_DNF_Pos) & I2C_CR1_DNF);
+}
+
+// Configure the I2C timings (SDA setup/hold time and SCL high/low period)
+// input:
+//   I2Cx - pointer to the I2C peripheral (I2C1, etc.)
+//   timing - the value for I2C_TIMINGR register
+// note: must be called only when I2C is disabled (PE bit in I2C_CR1 register is reset)
+static inline void i2c_config_timing(I2C_TypeDef* I2Cx, uint32_t timing) {
+	I2Cx->TIMINGR = timing;
+}
+
+// Generate START condition
+// input:
+//   I2Cx - pointer to the I2C peripheral (I2C1, etc.)
+//   addr - I2C device address
+// note: 7-bit addressing mode
+static inline void i2c_genstart(I2C_TypeDef* I2Cx, uint32_t addr) {
+	I2Cx->CR2 = (addr & I2C_CR2_SADD) | I2C_CR2_START | I2C_CR2_AUTOEND;
+}
+
+// Generate STOP condition
+// input:
+//   I2Cx - pointer to the I2C peripheral (I2C1, etc.)
+static inline void i2c_genstop(I2C_TypeDef* I2Cx) {
+	I2Cx->CR2 |= I2C_CR2_STOP;
+}
+
+
+// Function prototypes
+i2cstatus i2c_is_device_ready(I2C_TypeDef* I2Cx, uint8_t devAddr, uint32_t Trials);
+i2cstatus i2c_transmit(I2C_TypeDef* I2Cx, uint8_t devAddr, const uint8_t *pBuf, uint32_t nbytes, uint32_t flags);
+i2cstatus i2c_receive(I2C_TypeDef* I2Cx, uint8_t devAddr, uint8_t *pBuf, uint32_t nbytes);
+
+#endif // __I2C_H
-- 
cgit