From 5b8439bbdea9ad8c120cda408a97ed2e55e943d3 Mon Sep 17 00:00:00 2001 From: Armando Visconti Date: Thu, 6 Dec 2012 00:04:17 +0000 Subject: [PATCH] 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 --- drivers/i2c/designware_i2c.c | 28 +++++++++++++--------------- 1 file changed, 13 insertions(+), 15 deletions(-) diff --git a/drivers/i2c/designware_i2c.c b/drivers/i2c/designware_i2c.c index eab3131025..665387091a 100644 --- 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); } -- 2.25.1