diff options
Diffstat (limited to 'drivers/i2c/designware_i2c.c')
| -rw-r--r-- | drivers/i2c/designware_i2c.c | 64 |
1 files changed, 52 insertions, 12 deletions
diff --git a/drivers/i2c/designware_i2c.c b/drivers/i2c/designware_i2c.c index 9ccc2411a62..6daa90e7442 100644 --- a/drivers/i2c/designware_i2c.c +++ b/drivers/i2c/designware_i2c.c @@ -4,6 +4,7 @@ * Vipin Kumar, ST Micoelectronics, vipin.kumar@st.com. */ +#include <clk.h> #include <common.h> #include <dm.h> #include <i2c.h> @@ -35,6 +36,9 @@ struct dw_i2c { struct i2c_regs *regs; struct dw_scl_sda_cfg *scl_sda_cfg; struct reset_ctl_bulk resets; +#if CONFIG_IS_ENABLED(CLK) + struct clk clk; +#endif }; #ifdef CONFIG_SYS_I2C_DW_ENABLE_STATUS_UNSUPPORTED @@ -78,10 +82,12 @@ static int dw_i2c_enable(struct i2c_regs *i2c_base, bool enable) */ static unsigned int __dw_i2c_set_bus_speed(struct i2c_regs *i2c_base, struct dw_scl_sda_cfg *scl_sda_cfg, - unsigned int speed) + unsigned int speed, + unsigned int bus_mhz) { unsigned int cntl; unsigned int hcnt, lcnt; + unsigned int ena; int i2c_spd; if (speed >= I2C_MAX_SPEED) @@ -91,6 +97,9 @@ static unsigned int __dw_i2c_set_bus_speed(struct i2c_regs *i2c_base, else i2c_spd = IC_SPEED_MODE_STANDARD; + /* Get enable setting for restore later */ + ena = readl(&i2c_base->ic_enable) & IC_ENABLE_0B; + /* to set speed cltr must be disabled */ dw_i2c_enable(i2c_base, false); @@ -104,8 +113,8 @@ static unsigned int __dw_i2c_set_bus_speed(struct i2c_regs *i2c_base, hcnt = scl_sda_cfg->fs_hcnt; lcnt = scl_sda_cfg->fs_lcnt; } else { - hcnt = (IC_CLK * MIN_HS_SCL_HIGHTIME) / NANO_TO_MICRO; - lcnt = (IC_CLK * MIN_HS_SCL_LOWTIME) / NANO_TO_MICRO; + hcnt = (bus_mhz * MIN_HS_SCL_HIGHTIME) / NANO_TO_MICRO; + lcnt = (bus_mhz * MIN_HS_SCL_LOWTIME) / NANO_TO_MICRO; } writel(hcnt, &i2c_base->ic_hs_scl_hcnt); writel(lcnt, &i2c_base->ic_hs_scl_lcnt); @@ -118,8 +127,8 @@ static unsigned int __dw_i2c_set_bus_speed(struct i2c_regs *i2c_base, hcnt = scl_sda_cfg->ss_hcnt; lcnt = scl_sda_cfg->ss_lcnt; } else { - hcnt = (IC_CLK * MIN_SS_SCL_HIGHTIME) / NANO_TO_MICRO; - lcnt = (IC_CLK * MIN_SS_SCL_LOWTIME) / NANO_TO_MICRO; + hcnt = (bus_mhz * MIN_SS_SCL_HIGHTIME) / NANO_TO_MICRO; + lcnt = (bus_mhz * MIN_SS_SCL_LOWTIME) / NANO_TO_MICRO; } writel(hcnt, &i2c_base->ic_ss_scl_hcnt); writel(lcnt, &i2c_base->ic_ss_scl_lcnt); @@ -132,8 +141,8 @@ static unsigned int __dw_i2c_set_bus_speed(struct i2c_regs *i2c_base, hcnt = scl_sda_cfg->fs_hcnt; lcnt = scl_sda_cfg->fs_lcnt; } else { - hcnt = (IC_CLK * MIN_FS_SCL_HIGHTIME) / NANO_TO_MICRO; - lcnt = (IC_CLK * MIN_FS_SCL_LOWTIME) / NANO_TO_MICRO; + hcnt = (bus_mhz * MIN_FS_SCL_HIGHTIME) / NANO_TO_MICRO; + lcnt = (bus_mhz * MIN_FS_SCL_LOWTIME) / NANO_TO_MICRO; } writel(hcnt, &i2c_base->ic_fs_scl_hcnt); writel(lcnt, &i2c_base->ic_fs_scl_lcnt); @@ -146,8 +155,9 @@ static unsigned int __dw_i2c_set_bus_speed(struct i2c_regs *i2c_base, if (scl_sda_cfg) writel(scl_sda_cfg->sda_hold, &i2c_base->ic_sda_hold); - /* Enable back i2c now speed set */ - dw_i2c_enable(i2c_base, true); + /* Restore back i2c now speed set */ + if (ena == IC_ENABLE_0B) + dw_i2c_enable(i2c_base, true); return 0; } @@ -388,7 +398,7 @@ static int __dw_i2c_init(struct i2c_regs *i2c_base, int speed, int slaveaddr) writel(IC_TX_TL, &i2c_base->ic_tx_tl); writel(IC_STOP_DET, &i2c_base->ic_intr_mask); #ifndef CONFIG_DM_I2C - __dw_i2c_set_bus_speed(i2c_base, NULL, speed); + __dw_i2c_set_bus_speed(i2c_base, NULL, speed, IC_CLK); writel(slaveaddr, &i2c_base->ic_sar); #endif @@ -433,7 +443,7 @@ static unsigned int dw_i2c_set_bus_speed(struct i2c_adapter *adap, unsigned int speed) { adap->speed = speed; - return __dw_i2c_set_bus_speed(i2c_get_base(adap), NULL, speed); + return __dw_i2c_set_bus_speed(i2c_get_base(adap), NULL, speed, IC_CLK); } static void dw_i2c_init(struct i2c_adapter *adap, int speed, int slaveaddr) @@ -523,8 +533,20 @@ static int designware_i2c_xfer(struct udevice *bus, struct i2c_msg *msg, static int designware_i2c_set_bus_speed(struct udevice *bus, unsigned int speed) { struct dw_i2c *i2c = dev_get_priv(bus); + ulong rate; + +#if CONFIG_IS_ENABLED(CLK) + rate = clk_get_rate(&i2c->clk); + if (IS_ERR_VALUE(rate)) + return -EINVAL; - return __dw_i2c_set_bus_speed(i2c->regs, i2c->scl_sda_cfg, speed); + /* Convert to MHz */ + rate /= 1000000; +#else + rate = IC_CLK; +#endif + return __dw_i2c_set_bus_speed(i2c->regs, i2c->scl_sda_cfg, speed, + rate); } static int designware_i2c_probe_chip(struct udevice *bus, uint chip_addr, @@ -568,6 +590,19 @@ static int designware_i2c_probe(struct udevice *bus) else reset_deassert_bulk(&priv->resets); +#if CONFIG_IS_ENABLED(CLK) + ret = clk_get_by_index(bus, 0, &priv->clk); + if (ret) + return ret; + + ret = clk_enable(&priv->clk); + if (ret && ret != -ENOSYS && ret != -ENOTSUPP) { + clk_free(&priv->clk); + dev_err(bus, "failed to enable clock\n"); + return ret; + } +#endif + return __dw_i2c_init(priv->regs, 0, 0); } @@ -575,6 +610,11 @@ static int designware_i2c_remove(struct udevice *dev) { struct dw_i2c *priv = dev_get_priv(dev); +#if CONFIG_IS_ENABLED(CLK) + clk_disable(&priv->clk); + clk_free(&priv->clk); +#endif + return reset_release_bulk(&priv->resets); } |