// SPDX-License-Identifier: GPL-2.0+
/*
* (C) Copyright 2009
- * Vipin Kumar, ST Micoelectronics, vipin.kumar@st.com.
+ * Vipin Kumar, STMicroelectronics, vipin.kumar@st.com.
*/
#include <common.h>
#include <clk.h>
#include <dm.h>
#include <i2c.h>
+#include <log.h>
#include <malloc.h>
#include <pci.h>
#include <reset.h>
#include <asm/io.h>
+#include <linux/delay.h>
#include "designware_i2c.h"
#include <dm/device_compat.h>
#include <linux/err.h>
-#ifdef CONFIG_SYS_I2C_DW_ENABLE_STATUS_UNSUPPORTED
-static int dw_i2c_enable(struct i2c_regs *i2c_base, bool enable)
-{
- u32 ena = enable ? IC_ENABLE_0B : 0;
+/*
+ * This assigned unique hex value is constant and is derived from the two ASCII
+ * letters 'DW' followed by a 16-bit unsigned number
+ */
+#define DW_I2C_COMP_TYPE 0x44570140
- writel(ena, &i2c_base->ic_enable);
+/*
+ * This constant is used to calculate when during the clock high phase the data
+ * bit shall be read. The value was copied from the Linux v6.5 function
+ * i2c_dw_scl_hcnt() which provides the following explanation:
+ *
+ * "This is just an experimental rule: the tHD;STA period turned out to be
+ * proportinal to (_HCNT + 3). With this setting, we could meet both tHIGH and
+ * tHD;STA timing specs."
+ */
+#define T_HD_STA_OFFSET 3
- return 0;
-}
-#else
static int dw_i2c_enable(struct i2c_regs *i2c_base, bool enable)
{
u32 ena = enable ? IC_ENABLE_0B : 0;
return -ETIMEDOUT;
}
-#endif
/* High and low times in different speed modes (in ns) */
enum {
*
* @ic_clk: Input clock in Hz
* @period_ns: Period to represent, in ns
- * @return calculated count
+ * Return: calculated count
*/
static uint calc_counts(uint ic_clk, uint period_ns)
{
* @ic_clk: IC clock speed in Hz
* @spk_cnt: Spike-suppression count
* @config: Returns value to use
- * @return 0 if OK, -EINVAL if the calculation failed due to invalid data
+ * Return: 0 if OK, -EINVAL if the calculation failed due to invalid data
*/
static int dw_i2c_calc_timing(struct dw_i2c *priv, enum i2c_speed_mode mode,
int ic_clk, int spk_cnt,
min_tlow_cnt = calc_counts(ic_clk, info->min_scl_lowtime_ns);
min_thigh_cnt = calc_counts(ic_clk, info->min_scl_hightime_ns);
- debug("dw_i2c: period %d rise %d fall %d tlow %d thigh %d spk %d\n",
- period_cnt, rise_cnt, fall_cnt, min_tlow_cnt, min_thigh_cnt,
- spk_cnt);
+ debug("dw_i2c: mode %d, ic_clk %d, speed %d, period %d rise %d fall %d tlow %d thigh %d spk %d\n",
+ mode, ic_clk, info->speed, period_cnt, rise_cnt, fall_cnt,
+ min_tlow_cnt, min_thigh_cnt, spk_cnt);
/*
* Back-solve for hcnt and lcnt according to the following equations:
- * SCL_High_time = [(HCNT + IC_*_SPKLEN + 7) * ic_clk] + SCL_Fall_time
+ * SCL_High_time = [(HCNT + IC_*_SPKLEN + T_HD_STA_OFFSET) * ic_clk] + SCL_Fall_time
* SCL_Low_time = [(LCNT + 1) * ic_clk] - SCL_Fall_time + SCL_Rise_time
*/
- hcnt = min_thigh_cnt - fall_cnt - 7 - spk_cnt;
+ hcnt = min_thigh_cnt - fall_cnt - T_HD_STA_OFFSET - spk_cnt;
lcnt = min_tlow_cnt - rise_cnt + fall_cnt - 1;
if (hcnt < 0 || lcnt < 0) {
debug("dw_i2c: bad counts. hcnt = %d lcnt = %d\n", hcnt, lcnt);
- return -EINVAL;
+ return log_msg_ret("counts", -EINVAL);
}
/*
* Now add things back up to ensure the period is hit. If it is off,
* split the difference and bias to lcnt for remainder
*/
- tot = hcnt + lcnt + 7 + spk_cnt + rise_cnt + 1;
+ tot = hcnt + lcnt + T_HD_STA_OFFSET + spk_cnt + rise_cnt + 1;
if (tot < period_cnt) {
diff = (period_cnt - tot) / 2;
hcnt += diff;
lcnt += diff;
- tot = hcnt + lcnt + 7 + spk_cnt + rise_cnt + 1;
+ tot = hcnt + lcnt + T_HD_STA_OFFSET + spk_cnt + rise_cnt + 1;
lcnt += period_cnt - tot;
}
return 0;
}
-static int calc_bus_speed(struct dw_i2c *priv, int speed, ulong bus_clk,
- struct dw_i2c_speed_config *config)
+/**
+ * calc_bus_speed() - Calculate the config to use for a particular i2c speed
+ *
+ * @priv: Private information for the driver (NULL if not using driver model)
+ * @i2c_base: Registers for the I2C controller
+ * @speed: Required i2c speed in Hz
+ * @bus_clk: Input clock to the I2C controller in Hz (e.g. IC_CLK)
+ * @config: Returns the config to use for this speed
+ * Return: 0 if OK, -ve on error
+ */
+static int calc_bus_speed(struct dw_i2c *priv, struct i2c_regs *regs, int speed,
+ ulong bus_clk, struct dw_i2c_speed_config *config)
{
const struct dw_scl_sda_cfg *scl_sda_cfg = NULL;
- struct i2c_regs *regs = priv->regs;
enum i2c_speed_mode i2c_spd;
- u32 comp_param1;
int spk_cnt;
int ret;
- comp_param1 = readl(®s->comp_param1);
-
if (priv)
scl_sda_cfg = priv->scl_sda_cfg;
/* Allow high speed if there is no config, or the config allows it */
/* Check is high speed possible and fall back to fast mode if not */
if (i2c_spd == IC_SPEED_MODE_HIGH) {
+ u32 comp_param1;
+
+ comp_param1 = readl(®s->comp_param1);
if ((comp_param1 & DW_IC_COMP_PARAM_1_SPEED_MODE_MASK)
!= DW_IC_COMP_PARAM_1_SPEED_MODE_HIGH)
i2c_spd = IC_SPEED_MODE_FAST;
return 0;
}
-/*
- * _dw_i2c_set_bus_speed - Set the i2c speed
- * @speed: required i2c speed
+/**
+ * _dw_i2c_set_bus_speed() - Set the i2c speed
*
- * Set the i2c speed.
+ * @priv: Private information for the driver (NULL if not using driver model)
+ * @i2c_base: Registers for the I2C controller
+ * @speed: Required i2c speed in Hz
+ * @bus_clk: Input clock to the I2C controller in Hz (e.g. IC_CLK)
+ * Return: 0 if OK, -ve on error
*/
static int _dw_i2c_set_bus_speed(struct dw_i2c *priv, struct i2c_regs *i2c_base,
unsigned int speed, unsigned int bus_clk)
unsigned int ena;
int ret;
- ret = calc_bus_speed(priv, speed, bus_clk, &config);
+ ret = calc_bus_speed(priv, i2c_base, speed, bus_clk, &config);
if (ret)
return ret;
/* Restore back i2c now speed set */
if (ena == IC_ENABLE_0B)
dw_i2c_enable(i2c_base, true);
+ if (priv)
+ priv->config = config;
+
+ return 0;
+}
+
+int dw_i2c_gen_speed_config(const struct udevice *dev, int speed_hz,
+ struct dw_i2c_speed_config *config)
+{
+ struct dw_i2c *priv = dev_get_priv(dev);
+ ulong rate;
+ int ret;
+
+#if CONFIG_IS_ENABLED(CLK)
+ rate = clk_get_rate(&priv->clk);
+ if (IS_ERR_VALUE(rate))
+ return log_msg_ret("clk", -EINVAL);
+#else
+ rate = IC_CLK;
+#endif
+
+ ret = calc_bus_speed(priv, priv->regs, speed_hz, rate, config);
+ if (ret)
+ printf("%s: ret=%d\n", __func__, ret);
+ if (ret)
+ return log_msg_ret("calc_bus_speed", ret);
return 0;
}
writel(IC_RX_TL, &i2c_base->ic_rx_tl);
writel(IC_TX_TL, &i2c_base->ic_tx_tl);
writel(IC_STOP_DET, &i2c_base->ic_intr_mask);
-#ifndef CONFIG_DM_I2C
+#if !CONFIG_IS_ENABLED(DM_I2C)
_dw_i2c_set_bus_speed(NULL, i2c_base, speed, IC_CLK);
writel(slaveaddr, &i2c_base->ic_sar);
#endif
return 0;
}
-#ifndef CONFIG_DM_I2C
+#if !CONFIG_IS_ENABLED(DM_I2C)
/*
* The legacy I2C functions. These need to get removed once
* all users of this driver are converted to DM.
dw_i2c_write, dw_i2c_set_bus_speed,
CONFIG_SYS_I2C_SPEED, CONFIG_SYS_I2C_SLAVE, 0)
-#if CONFIG_SYS_I2C_BUS_MAX >= 2
-U_BOOT_I2C_ADAP_COMPLETE(dw_1, dw_i2c_init, dw_i2c_probe, dw_i2c_read,
- dw_i2c_write, dw_i2c_set_bus_speed,
- CONFIG_SYS_I2C_SPEED1, CONFIG_SYS_I2C_SLAVE1, 1)
-#endif
-
-#if CONFIG_SYS_I2C_BUS_MAX >= 3
-U_BOOT_I2C_ADAP_COMPLETE(dw_2, dw_i2c_init, dw_i2c_probe, dw_i2c_read,
- dw_i2c_write, dw_i2c_set_bus_speed,
- CONFIG_SYS_I2C_SPEED2, CONFIG_SYS_I2C_SLAVE2, 2)
-#endif
-
-#if CONFIG_SYS_I2C_BUS_MAX >= 4
-U_BOOT_I2C_ADAP_COMPLETE(dw_3, dw_i2c_init, dw_i2c_probe, dw_i2c_read,
- dw_i2c_write, dw_i2c_set_bus_speed,
- CONFIG_SYS_I2C_SPEED3, CONFIG_SYS_I2C_SLAVE3, 3)
-#endif
-
#else /* CONFIG_DM_I2C */
/* The DM I2C functions */
#if CONFIG_IS_ENABLED(CLK)
rate = clk_get_rate(&i2c->clk);
if (IS_ERR_VALUE(rate))
- return -EINVAL;
+ return log_ret(-EINVAL);
#else
rate = IC_CLK;
#endif
return ret;
}
-int designware_i2c_ofdata_to_platdata(struct udevice *bus)
+int designware_i2c_of_to_plat(struct udevice *bus)
{
struct dw_i2c *priv = dev_get_priv(bus);
int ret;
if (!priv->regs)
- priv->regs = (struct i2c_regs *)devfdt_get_addr_ptr(bus);
+ priv->regs = dev_read_addr_ptr(bus);
dev_read_u32(bus, "i2c-scl-rising-time-ns", &priv->scl_rise_time_ns);
dev_read_u32(bus, "i2c-scl-falling-time-ns", &priv->scl_fall_time_ns);
dev_read_u32(bus, "i2c-sda-hold-time-ns", &priv->sda_hold_time_ns);
ret = reset_get_bulk(bus, &priv->resets);
- if (ret)
- dev_warn(bus, "Can't get reset: %d\n", ret);
- else
+ if (ret) {
+ if (ret != -ENOTSUPP)
+ dev_warn(bus, "Can't get reset: %d\n", ret);
+ } else {
reset_deassert_bulk(&priv->resets);
+ }
#if CONFIG_IS_ENABLED(CLK)
ret = clk_get_by_index(bus, 0, &priv->clk);
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;
}
int designware_i2c_probe(struct udevice *bus)
{
struct dw_i2c *priv = dev_get_priv(bus);
+ uint comp_type;
+
+ comp_type = readl(&priv->regs->comp_type);
+ if (comp_type != DW_I2C_COMP_TYPE) {
+ log_err("I2C bus %s has unknown type %#x\n", bus->name,
+ comp_type);
+ return -ENXIO;
+ }
+
+ log_debug("I2C bus %s version %#x\n", bus->name,
+ readl(&priv->regs->comp_version));
return __dw_i2c_init(priv->regs, 0, 0);
}
#if CONFIG_IS_ENABLED(CLK)
clk_disable(&priv->clk);
- clk_free(&priv->clk);
#endif
return reset_release_bulk(&priv->resets);
.name = "i2c_designware",
.id = UCLASS_I2C,
.of_match = designware_i2c_ids,
- .ofdata_to_platdata = designware_i2c_ofdata_to_platdata,
+ .of_to_plat = designware_i2c_of_to_plat,
.probe = designware_i2c_probe,
- .priv_auto_alloc_size = sizeof(struct dw_i2c),
+ .priv_auto = sizeof(struct dw_i2c),
.remove = designware_i2c_remove,
.flags = DM_FLAG_OS_PREPARE,
.ops = &designware_i2c_ops,