}
/* Enable transaction halt on start bit */
- if (!i2c->last_msg && i2c->line_status & LINESTAT_START_BIT_DET) {
+ if (!i2c->last_msg && line_status & LINESTAT_START_BIT_DET) {
img_i2c_transaction_halt(i2c, true);
/* we're no longer interested in the slave event */
i2c->int_enable &= ~INT_SLAVE_EVENT;
i2c->last_msg = (i == num - 1);
reinit_completion(&i2c->msg_complete);
+ /*
+ * Clear line status and all interrupts before starting a
+ * transfer, as we may have unserviced interrupts from
+ * previous transfers that might be handled in the context
+ * of the new transfer.
+ */
+ img_i2c_writel(i2c, SCB_INT_CLEAR_REG, ~0);
+ img_i2c_writel(i2c, SCB_CLEAR_REG, ~0);
+
if (atomic)
img_i2c_atomic_start(i2c);
else if (msg->flags & I2C_M_RD)
/* Fencing enabled by default. */
i2c->need_wr_rd_fence = true;
- bitrate_khz = i2c->bitrate / 1000;
- clk_khz = clk_get_rate(i2c->scb_clk) / 1000;
-
/* Determine what mode we're in from the bitrate */
timing = timings[0];
for (i = 0; i < ARRAY_SIZE(timings); i++) {
break;
}
}
+ if (i2c->bitrate > timings[ARRAY_SIZE(timings) - 1].max_bitrate) {
+ dev_warn(i2c->adap.dev.parent,
+ "requested bitrate (%u) is higher than the max bitrate supported (%u)\n",
+ i2c->bitrate,
+ timings[ARRAY_SIZE(timings) - 1].max_bitrate);
+ timing = timings[ARRAY_SIZE(timings) - 1];
+ i2c->bitrate = timing.max_bitrate;
+ }
+
+ bitrate_khz = i2c->bitrate / 1000;
+ clk_khz = clk_get_rate(i2c->scb_clk) / 1000;
/* Find the prescale that would give us that inc (approx delay = 0) */
prescale = SCB_OPT_INC * clk_khz / (256 * 16 * bitrate_khz);
((bitrate_khz * clk_period) / 2))
int_bitrate++;
- /* Setup TCKH value */
- tckh = DIV_ROUND_UP(timing.tckh, clk_period);
+ /*
+ * Setup clock duty cycle, start with 50% and adjust TCKH and TCKL
+ * values from there if they don't meet minimum timing requirements
+ */
+ tckh = int_bitrate / 2;
+ tckl = int_bitrate - tckh;
- if (tckh > 0)
- data = tckh - 1;
- else
- data = 0;
+ /* Adjust TCKH and TCKL values */
+ data = DIV_ROUND_UP(timing.tckl, clk_period);
- img_i2c_writel(i2c, SCB_TIME_TCKH_REG, data);
+ if (tckl < data) {
+ tckl = data;
+ tckh = int_bitrate - tckl;
+ }
- /* Setup TCKL value */
- tckl = int_bitrate - tckh;
+ if (tckh > 0)
+ --tckh;
if (tckl > 0)
- data = tckl - 1;
- else
- data = 0;
+ --tckl;
- img_i2c_writel(i2c, SCB_TIME_TCKL_REG, data);
+ img_i2c_writel(i2c, SCB_TIME_TCKH_REG, tckh);
+ img_i2c_writel(i2c, SCB_TIME_TCKL_REG, tckl);
/* Setup TSDH value */
tsdh = DIV_ROUND_UP(timing.tsdh, clk_period);