i2c:designware Turn off the ctrl when setting the speed
The designware i2c controller must be turned off before
setting the speed in IC_CON register, as stated in the
section 6.3.1 of the dw_apb_i2c_db.pdf.
Signed-off-by: Michel Sanches <michel.sanches@st.com>
Signed-off-by: Armando Visconti <armando.visconti@st.com>
Signed-off-by: Amit Virdi <amit.virdi@st.com>
diff --git a/drivers/i2c/designware_i2c.c b/drivers/i2c/designware_i2c.c
index d352146..6d118ac 100644
--- a/drivers/i2c/designware_i2c.c
+++ b/drivers/i2c/designware_i2c.c
@@ -40,6 +40,13 @@
unsigned int cntl;
unsigned int hcnt, lcnt;
unsigned int high, low;
+ unsigned int enbl;
+
+ /* to set speed cltr must be disabled */
+ enbl = readl(&i2c_regs_p->ic_enable);
+ enbl &= ~IC_ENABLE_0B;
+ writel(enbl, &i2c_regs_p->ic_enable);
+
cntl = (readl(&i2c_regs_p->ic_con) & (~IC_CON_SPD_MSK));
@@ -71,6 +78,10 @@
lcnt = (IC_CLK * low) / NANO_TO_MICRO;
writel(lcnt, &i2c_regs_p->ic_fs_scl_lcnt);
+
+ /* re-enable i2c ctrl back now that speed is set */
+ enbl |= IC_ENABLE_0B;
+ writel(enbl, &i2c_regs_p->ic_enable);
}
/*