diff options
| author | Pierre-Yves MORDRET <pierre-yves.mordret@st.com> | 2018-11-19 12:03:32 +0100 |
|---|---|---|
| committer | Wolfram Sang <wsa@the-dreams.de> | 2018-11-27 13:08:17 +0100 |
| commit | cb944fb973bcd326bc99a5381f5fb109c0b9de95 (patch) | |
| tree | bb8982c27c797877ed55da9aa946813be28a8114 /drivers/i2c/busses | |
| parent | dt-bindings: i2c-stm32: SYSCFG Fast Mode Plus support for I2C STM32F7 (diff) | |
| download | linux-cb944fb973bcd326bc99a5381f5fb109c0b9de95.tar.xz linux-cb944fb973bcd326bc99a5381f5fb109c0b9de95.zip | |
i2c: stm32f7: SYSCFG Fast Mode Plus support for I2C STM32F7
Read SYSCFG bindings to set Fast Mode Plus bits if Fast Mode Plus
speed is selected.
Signed-off-by: Pierre-Yves MORDRET <pierre-yves.mordret@st.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Diffstat (limited to 'drivers/i2c/busses')
| -rw-r--r-- | drivers/i2c/busses/i2c-stm32f7.c | 38 |
1 files changed, 35 insertions, 3 deletions
diff --git a/drivers/i2c/busses/i2c-stm32f7.c b/drivers/i2c/busses/i2c-stm32f7.c index 62d023e737d9..e9f0c0bd774d 100644 --- a/drivers/i2c/busses/i2c-stm32f7.c +++ b/drivers/i2c/busses/i2c-stm32f7.c @@ -21,12 +21,14 @@ #include <linux/interrupt.h> #include <linux/io.h> #include <linux/iopoll.h> +#include <linux/mfd/syscon.h> #include <linux/module.h> #include <linux/of.h> #include <linux/of_address.h> #include <linux/of_irq.h> #include <linux/of_platform.h> #include <linux/platform_device.h> +#include <linux/regmap.h> #include <linux/reset.h> #include <linux/slab.h> @@ -276,6 +278,7 @@ struct stm32f7_i2c_msg { * slave) * @dma: dma data * @use_dma: boolean to know if dma is used in the current transfer + * @regmap: holds SYSCFG phandle for Fast Mode Plus bits */ struct stm32f7_i2c_dev { struct i2c_adapter adap; @@ -296,6 +299,7 @@ struct stm32f7_i2c_dev { bool master_mode; struct stm32_i2c_dma *dma; bool use_dma; + struct regmap *regmap; }; /** @@ -1763,6 +1767,30 @@ static int stm32f7_i2c_unreg_slave(struct i2c_client *slave) return 0; } +static int stm32f7_i2c_setup_fm_plus_bits(struct platform_device *pdev, + struct stm32f7_i2c_dev *i2c_dev) +{ + struct device_node *np = pdev->dev.of_node; + int ret; + u32 reg, mask; + + i2c_dev->regmap = syscon_regmap_lookup_by_phandle(np, "st,syscfg-fmp"); + if (IS_ERR(i2c_dev->regmap)) { + /* Optional */ + return 0; + } + + ret = of_property_read_u32_index(np, "st,syscfg-fmp", 1, ®); + if (ret) + return ret; + + ret = of_property_read_u32_index(np, "st,syscfg-fmp", 2, &mask); + if (ret) + return ret; + + return regmap_update_bits(i2c_dev->regmap, reg, mask, mask); +} + static u32 stm32f7_i2c_func(struct i2c_adapter *adap) { return I2C_FUNC_I2C | I2C_FUNC_10BIT_ADDR | I2C_FUNC_SLAVE | @@ -1828,12 +1856,16 @@ static int stm32f7_i2c_probe(struct platform_device *pdev) i2c_dev->speed = STM32_I2C_SPEED_STANDARD; ret = device_property_read_u32(&pdev->dev, "clock-frequency", &clk_rate); - if (!ret && clk_rate >= 1000000) + if (!ret && clk_rate >= 1000000) { i2c_dev->speed = STM32_I2C_SPEED_FAST_PLUS; - else if (!ret && clk_rate >= 400000) + ret = stm32f7_i2c_setup_fm_plus_bits(pdev, i2c_dev); + if (ret) + goto clk_free; + } else if (!ret && clk_rate >= 400000) { i2c_dev->speed = STM32_I2C_SPEED_FAST; - else if (!ret && clk_rate >= 100000) + } else if (!ret && clk_rate >= 100000) { i2c_dev->speed = STM32_I2C_SPEED_STANDARD; + } rst = devm_reset_control_get(&pdev->dev, NULL); if (IS_ERR(rst)) { |