diff options
| -rw-r--r-- | drivers/i2c/designware_i2c.c | 51 | ||||
| -rw-r--r-- | drivers/i2c/i2c-uclass.c | 2 | ||||
| -rw-r--r-- | drivers/misc/i2c_eeprom.c | 8 |
3 files changed, 48 insertions, 13 deletions
diff --git a/drivers/i2c/designware_i2c.c b/drivers/i2c/designware_i2c.c index 42ee7d523e..3616e2105f 100644 --- a/drivers/i2c/designware_i2c.c +++ b/drivers/i2c/designware_i2c.c @@ -18,6 +18,12 @@ #include <dm/device_compat.h> #include <linux/err.h> +/* + * 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 + #ifdef CONFIG_SYS_I2C_DW_ENABLE_STATUS_UNSUPPORTED static int dw_i2c_enable(struct i2c_regs *i2c_base, bool enable) { @@ -199,18 +205,24 @@ static int dw_i2c_calc_timing(struct dw_i2c *priv, enum i2c_speed_mode mode, 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 */ @@ -225,6 +237,9 @@ static int calc_bus_speed(struct dw_i2c *priv, int speed, ulong bus_clk, /* 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; @@ -260,11 +275,14 @@ static int calc_bus_speed(struct dw_i2c *priv, int speed, ulong bus_clk, 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) @@ -274,7 +292,7 @@ static int _dw_i2c_set_bus_speed(struct dw_i2c *priv, struct i2c_regs *i2c_base, 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; @@ -754,6 +772,17 @@ int designware_i2c_ofdata_to_platdata(struct udevice *bus) 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_info("I2C bus %s version %#x\n", bus->name, + readl(&priv->regs->comp_version)); return __dw_i2c_init(priv->regs, 0, 0); } diff --git a/drivers/i2c/i2c-uclass.c b/drivers/i2c/i2c-uclass.c index 8166df7ba6..8bc69e870f 100644 --- a/drivers/i2c/i2c-uclass.c +++ b/drivers/i2c/i2c-uclass.c @@ -516,7 +516,7 @@ int i2c_deblock_gpio_loop(struct gpio_desc *sda_pin, udelay(delay); /* Toggle SCL until slave release SDA */ - while (scl_count-- >= 0) { + for (; scl_count; --scl_count) { i2c_gpio_set_pin(scl_pin, 1); udelay(delay); i2c_gpio_set_pin(scl_pin, 0); diff --git a/drivers/misc/i2c_eeprom.c b/drivers/misc/i2c_eeprom.c index ed23a62384..45c34d388c 100644 --- a/drivers/misc/i2c_eeprom.c +++ b/drivers/misc/i2c_eeprom.c @@ -18,6 +18,7 @@ struct i2c_eeprom_drv_data { u32 pagesize; /* page size in bytes */ u32 addr_offset_mask; /* bits in addr used for offset overflow */ u32 offset_len; /* size in bytes of offset */ + u32 start_offset; /* valid start offset inside memory, by default 0 */ }; int i2c_eeprom_read(struct udevice *dev, int offset, uint8_t *buf, int size) @@ -148,7 +149,11 @@ static int i2c_eeprom_std_probe(struct udevice *dev) i2c_set_chip_addr_offset_mask(dev, data->addr_offset_mask); /* Verify that the chip is functional */ - ret = i2c_eeprom_read(dev, 0, &test_byte, 1); + /* + * Not all eeproms start from offset 0. Valid offset is available + * in the platform data struct. + */ + ret = i2c_eeprom_read(dev, data->start_offset, &test_byte, 1); if (ret) return -ENODEV; @@ -216,6 +221,7 @@ static const struct i2c_eeprom_drv_data atmel24mac402_data = { .pagesize = 16, .addr_offset_mask = 0, .offset_len = 1, + .start_offset = 0x80, }; static const struct i2c_eeprom_drv_data atmel24c32_data = { |