From patchwork Fri Jan 3 22:26:43 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Simon Glass X-Patchwork-Id: 239086 List-Id: U-Boot discussion From: sjg at chromium.org (Simon Glass) Date: Fri, 3 Jan 2020 15:26:43 -0700 Subject: [PATCH v2 12/19] i2c: designware_i2c: Add spike supression In-Reply-To: <20200103222650.32592-1-sjg@chromium.org> References: <20200103222650.32592-1-sjg@chromium.org> Message-ID: <20200103152643.v2.12.I8edeb1d807ab73060bd6a5d028f7af8537cbf2f2@changeid> Some versions of this peripheral include a spike-suppression phase of the bus. Add support for this. Signed-off-by: Simon Glass Reviewed-by: Heiko Schocher --- Changes in v2: - Add a few more clean-up patches for i2c drivers/i2c/designware_i2c.c | 10 +++++++++- drivers/i2c/designware_i2c.h | 2 ++ drivers/i2c/designware_i2c_pci.c | 2 ++ 3 files changed, 13 insertions(+), 1 deletion(-) diff --git a/drivers/i2c/designware_i2c.c b/drivers/i2c/designware_i2c.c index 0069602103..4aee25c543 100644 --- a/drivers/i2c/designware_i2c.c +++ b/drivers/i2c/designware_i2c.c @@ -220,6 +220,7 @@ static unsigned int __dw_i2c_set_bus_speed(struct dw_i2c *priv, enum i2c_speed_mode i2c_spd; unsigned int cntl; unsigned int ena; + int spk_cnt; int ret; if (priv) @@ -241,6 +242,13 @@ static unsigned int __dw_i2c_set_bus_speed(struct dw_i2c *priv, cntl = (readl(&i2c_base->ic_con) & (~IC_CON_SPD_MSK)); + /* Get the proper spike-suppression count based on target speed */ + if (!priv || !priv->has_spk_cnt) + spk_cnt = 0; + else if (i2c_spd >= IC_SPEED_MODE_HIGH) + spk_cnt = readl(&i2c_base->hs_spklen); + else + spk_cnt = readl(&i2c_base->fs_spklen); if (scl_sda_cfg) { config.sda_hold = scl_sda_cfg->sda_hold; if (i2c_spd == IC_SPEED_MODE_STANDARD) { @@ -251,7 +259,7 @@ static unsigned int __dw_i2c_set_bus_speed(struct dw_i2c *priv, config.scl_lcnt = scl_sda_cfg->fs_lcnt; } } else { - ret = dw_i2c_calc_timing(priv, i2c_spd, bus_clk, 0, + ret = dw_i2c_calc_timing(priv, i2c_spd, bus_clk, spk_cnt, &config); if (ret) return log_msg_ret("gen_confg", ret); diff --git a/drivers/i2c/designware_i2c.h b/drivers/i2c/designware_i2c.h index 55e440f0c0..2c572a9e1f 100644 --- a/drivers/i2c/designware_i2c.h +++ b/drivers/i2c/designware_i2c.h @@ -175,6 +175,7 @@ struct dw_scl_sda_cfg { * @scl_rise_time_ns: Configured SCL rise time in nanoseconds * @scl_fall_time_ns: Configured SCL fall time in nanoseconds * @sda_hold_time_ns: Configured SDA hold time in nanoseconds + * @has_spk_cnt: true if the spike-count register is present * @clk: Clock input to the I2C controller */ struct dw_i2c { @@ -184,6 +185,7 @@ struct dw_i2c { u32 scl_rise_time_ns; u32 scl_fall_time_ns; u32 sda_hold_time_ns; + bool has_spk_cnt; #if CONFIG_IS_ENABLED(CLK) struct clk clk; #endif diff --git a/drivers/i2c/designware_i2c_pci.c b/drivers/i2c/designware_i2c_pci.c index 2b974a07c3..50f03e3d90 100644 --- a/drivers/i2c/designware_i2c_pci.c +++ b/drivers/i2c/designware_i2c_pci.c @@ -62,6 +62,8 @@ static int designware_i2c_pci_ofdata_to_platdata(struct udevice *dev) if (IS_ENABLED(CONFIG_INTEL_BAYTRAIL)) /* Use BayTrail specific timing values */ priv->scl_sda_cfg = &byt_config; + if (dev_get_driver_data(dev) == INTEL_APL) + priv->has_spk_cnt = true; return designware_i2c_ofdata_to_platdata(dev); }