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Diffstat (limited to 'drivers/i2c/busses/i2c-rk3x.c')
-rw-r--r--drivers/i2c/busses/i2c-rk3x.c17
1 files changed, 10 insertions, 7 deletions
diff --git a/drivers/i2c/busses/i2c-rk3x.c b/drivers/i2c/busses/i2c-rk3x.c
index 69e11853e8bf..b38b0529946a 100644
--- a/drivers/i2c/busses/i2c-rk3x.c
+++ b/drivers/i2c/busses/i2c-rk3x.c
@@ -238,7 +238,7 @@ static void rk3x_i2c_fill_transmit_buf(struct rk3x_i2c *i2c)
for (i = 0; i < 8; ++i) {
val = 0;
for (j = 0; j < 4; ++j) {
- if (i2c->processed == i2c->msg->len)
+ if ((i2c->processed == i2c->msg->len) && (cnt != 0))
break;
if (i2c->processed == 0 && cnt == 0)
@@ -323,6 +323,10 @@ static void rk3x_i2c_handle_read(struct rk3x_i2c *i2c, unsigned int ipd)
/* ack interrupt */
i2c_writel(i2c, REG_INT_MBRF, REG_IPD);
+ /* Can only handle a maximum of 32 bytes at a time */
+ if (len > 32)
+ len = 32;
+
/* read the data from receive buffer */
for (i = 0; i < len; ++i) {
if (i % 4 == 0)
@@ -429,12 +433,11 @@ static void rk3x_i2c_set_scl_rate(struct rk3x_i2c *i2c, unsigned long scl_rate)
unsigned long i2c_rate = clk_get_rate(i2c->clk);
unsigned int div;
- /* SCL rate = (clk rate) / (8 * DIV) */
- div = DIV_ROUND_UP(i2c_rate, scl_rate * 8);
-
- /* The lower and upper half of the CLKDIV reg describe the length of
- * SCL low & high periods. */
- div = DIV_ROUND_UP(div, 2);
+ /* set DIV = DIVH = DIVL
+ * SCL rate = (clk rate) / (8 * (DIVH + 1 + DIVL + 1))
+ * = (clk rate) / (16 * (DIV + 1))
+ */
+ div = DIV_ROUND_UP(i2c_rate, scl_rate * 16) - 1;
i2c_writel(i2c, (div << 16) | (div & 0xffff), REG_CLKDIV);
}