Merge pull request #427 from ChibiOS/i2c_eeprom_freq

hal_ee24xx: add bus frequency parameter

Author: fpoussin

os/hal/include/hal_ee24xx.h

@@ -26,6 +26,11 @@ typedef struct {
    * Address of IC on I2C bus.
    */
   i2caddr_t     addr;
+  /**
+   * I2C bus frequency in Hz. Used to compute transaction timeouts.
+   * If zero, a conservative default will be used by the driver.
+   */
+  uint32_t      bus_hz;
   /**
    * Pointer to write buffer. The safest size is (pagesize + 2)
    * Declare with CC_SECTION(".nocache") ... if using I2C with DMA to avoid

os/hal/src/hal_ee24xx.c

@@ -59,7 +59,8 @@ Write cycle time (byte or page) - 5 ms
 #define EEPROM_I2C_CLOCK (i2cp->config->clock_speed)
 #endif
 */
-#define EEPROM_I2C_CLOCK 400000
+/* Fallback frequency if not provided via config and not detectable */
+#define EEPROM_I2C_CLOCK_DEFAULT 400000U
 
 /*
  ******************************************************************************
@@ -98,12 +99,13 @@ Write cycle time (byte or page) - 5 ms
 /**
  * @brief     Calculates requred timeout.
  */
-static systime_t calc_timeout(I2CDriver *i2cp, size_t txbytes, size_t rxbytes) {
+static systime_t calc_timeout(I2CDriver *i2cp, size_t txbytes, size_t rxbytes, uint32_t bus_hz) {
   (void)i2cp;
   const uint32_t bitsinbyte = 10;
   uint32_t tmo;
+  uint32_t freq = bus_hz ? bus_hz : EEPROM_I2C_CLOCK_DEFAULT;
   tmo = ((txbytes + rxbytes + 1) * bitsinbyte * 1000);
-  tmo /= EEPROM_I2C_CLOCK;
+  tmo /= freq;
   tmo += 10; /* some additional milliseconds to be safer */
   return TIME_MS2I(tmo);
 }
@@ -126,7 +128,7 @@ static msg_t eeprom_read(const I2CEepromFileConfig *eepcfg,
   const bool one_byte_addr = (eepcfg->size <= 2048U);
   const uint32_t eff_off = offset + eepcfg->barrier_low;
   const size_t addr_bytes = one_byte_addr ? 1U : 2U;
-  systime_t tmo = calc_timeout(eepcfg->i2cp, addr_bytes, len);
+  systime_t tmo = calc_timeout(eepcfg->i2cp, addr_bytes, len, eepcfg->bus_hz);
 
   osalDbgAssert(((len <= eepcfg->size) && ((offset + len) <= eepcfg->size)),
              "out of device bounds");
@@ -175,7 +177,7 @@ static msg_t eeprom_write(const I2CEepromFileConfig *eepcfg, uint32_t offset,
   const bool one_byte_addr = (eepcfg->size <= 2048U);
   const uint32_t eff_off = offset + eepcfg->barrier_low;
   const size_t addr_bytes = one_byte_addr ? 1U : 2U;
-  systime_t tmo = calc_timeout(eepcfg->i2cp, (len + addr_bytes), 0);
+  systime_t tmo = calc_timeout(eepcfg->i2cp, (len + addr_bytes), 0, eepcfg->bus_hz);
 
   osalDbgAssert(((len <= eepcfg->size) && ((offset + len) <= eepcfg->size)),
              "out of device bounds");