designware_i2c: Fixed the setting of the i2c bus speed

There are three couple (hcnt/lcnt) of registers for each
speed (SS/FS/HS). The driver needs to set the proper couple
of regs according to what speed we are setting.

Signed-off-by: Armando Visconti <armando.visconti@st.com>

diff --git a/drivers/i2c/designware_i2c.c b/drivers/i2c/designware_i2c.c
index eab3131..6653870 100644 (file)
--- a/drivers/i2c/designware_i2c.c
+++ b/drivers/i2c/designware_i2c.c
@@ -44,7 +44,6 @@ static void set_speed(int i2c_spd)
 {
        unsigned int cntl;
        unsigned int hcnt, lcnt;
-       unsigned int high, low;
        unsigned int enbl;
 
        /* to set speed cltr must be disabled */
@@ -52,39 +51,38 @@ static void set_speed(int i2c_spd)
        enbl &= ~IC_ENABLE_0B;
        writel(enbl, &i2c_regs_p->ic_enable);
 
-
        cntl = (readl(&i2c_regs_p->ic_con) & (~IC_CON_SPD_MSK));
 
        switch (i2c_spd) {
        case IC_SPEED_MODE_MAX:
                cntl |= IC_CON_SPD_HS;
-               high = MIN_HS_SCL_HIGHTIME;
-               low = MIN_HS_SCL_LOWTIME;
+               hcnt = (IC_CLK * MIN_HS_SCL_HIGHTIME) / NANO_TO_MICRO;
+               writel(hcnt, &i2c_regs_p->ic_hs_scl_hcnt);
+               lcnt = (IC_CLK * MIN_HS_SCL_LOWTIME) / NANO_TO_MICRO;
+               writel(lcnt, &i2c_regs_p->ic_hs_scl_lcnt);
                break;
 
        case IC_SPEED_MODE_STANDARD:
                cntl |= IC_CON_SPD_SS;
-               high = MIN_SS_SCL_HIGHTIME;
-               low = MIN_SS_SCL_LOWTIME;
+               hcnt = (IC_CLK * MIN_SS_SCL_HIGHTIME) / NANO_TO_MICRO;
+               writel(hcnt, &i2c_regs_p->ic_ss_scl_hcnt);
+               lcnt = (IC_CLK * MIN_SS_SCL_LOWTIME) / NANO_TO_MICRO;
+               writel(lcnt, &i2c_regs_p->ic_ss_scl_lcnt);
                break;
 
        case IC_SPEED_MODE_FAST:
        default:
                cntl |= IC_CON_SPD_FS;
-               high = MIN_FS_SCL_HIGHTIME;
-               low = MIN_FS_SCL_LOWTIME;
+               hcnt = (IC_CLK * MIN_FS_SCL_HIGHTIME) / NANO_TO_MICRO;
+               writel(hcnt, &i2c_regs_p->ic_fs_scl_hcnt);
+               lcnt = (IC_CLK * MIN_FS_SCL_LOWTIME) / NANO_TO_MICRO;
+               writel(lcnt, &i2c_regs_p->ic_fs_scl_lcnt);
                break;
        }
 
        writel(cntl, &i2c_regs_p->ic_con);
 
-       hcnt = (IC_CLK * high) / NANO_TO_MICRO;
-       writel(hcnt, &i2c_regs_p->ic_fs_scl_hcnt);
-
-       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 */
+       /* Enable back i2c now speed set */
        enbl |= IC_ENABLE_0B;
        writel(enbl, &i2c_regs_p->ic_enable);
 }