| Message ID | 20220530114056.8722-1-potin.lai.pt@gmail.com |
|---|---|
| State | New |
| Headers | show |
| Series | [1/1] aspeed: i2c: add manual clock setup feature | expand |
Patrick Williams 於 31/05/2022 9:47 pm 寫道: > On Mon, May 30, 2022 at 07:40:56PM +0800, Potin Lai wrote: >> From: Porin Lai <potin.lai.pt@gmail.com> >> >> Add properties for manual tuning i2c clock timing register. >> >> * aspeed,i2c-manual-clk: Enable aspeed i2c clock manual setup >> * aspeed,i2c-base-clk-div: Base Clock divisor (tBaseClk) >> * aspeed,i2c-clk-high-cycle: Cycles of clock-high pulse (tClkHigh) >> * aspeed,i2c-clk-low-cycle: Cycles of clock-low pulse (tClkLow) > Do we need to add these to > Documentation/devicetree/bindings/i2c/aspeed,i2c.yaml ? Sorry, I wasn't notice the yaml file, I will update the documentation in next version. Potin >> Signed-off-by: Potin Lai <potin.lai.pt@gmail.com> >> --- >> drivers/i2c/busses/i2c-aspeed.c | 55 ++++++++++++++++++++++++++++++++- >> 1 file changed, 54 insertions(+), 1 deletion(-) >> >> diff --git a/drivers/i2c/busses/i2c-aspeed.c b/drivers/i2c/busses/i2c-aspeed.c >> index 67e8b97c0c95..1f4b5c4b5bf4 100644 >> --- a/drivers/i2c/busses/i2c-aspeed.c >> +++ b/drivers/i2c/busses/i2c-aspeed.c >> @@ -898,6 +898,56 @@ static int aspeed_i2c_init_clk(struct aspeed_i2c_bus *bus) >> return 0; >> } >> >> +/* precondition: bus.lock has been acquired. */ >> +static int aspeed_i2c_manual_clk_setup(struct aspeed_i2c_bus *bus) >> +{ >> + u32 divisor, clk_high, clk_low, clk_reg_val; >> + >> + if (device_property_read_u32(bus->dev, "aspeed,i2c-base-clk-div", >> + &divisor) != 0) { >> + dev_err(bus->dev, "Could not read aspeed,i2c-base-clk-div\n"); >> + return -EINVAL; >> + } else if (divisor > ASPEED_I2CD_TIME_BASE_DIVISOR_MASK) { >> + dev_err(bus->dev, "Invalid aspeed,i2c-base-clk-div: %u\n", >> + divisor); >> + return -EINVAL; >> + } >> + >> + if (device_property_read_u32(bus->dev, "aspeed,i2c-clk-high-cycle", >> + &clk_high) != 0) { >> + dev_err(bus->dev, "Could not read aspeed,i2c-clk-high-cycle\n"); >> + return -EINVAL; >> + } else if (clk_high > ASPEED_I2CD_TIME_SCL_REG_MAX) { >> + dev_err(bus->dev, "Invalid aspeed,i2c-clk-high-cycle: %u\n", >> + clk_high); >> + return -EINVAL; >> + } >> + >> + if (device_property_read_u32(bus->dev, "aspeed,i2c-clk-low-cycle", >> + &clk_low) != 0) { >> + dev_err(bus->dev, "Could not read aspeed,i2c-clk-low-cycle\n"); >> + return -EINVAL; >> + } else if (clk_low > ASPEED_I2CD_TIME_SCL_REG_MAX) { >> + dev_err(bus->dev, "Invalid aspeed,i2c-clk-low-cycle: %u\n", >> + clk_low); >> + return -EINVAL; >> + } >> + >> + clk_reg_val = readl(bus->base + ASPEED_I2C_AC_TIMING_REG1); >> + clk_reg_val &= (ASPEED_I2CD_TIME_TBUF_MASK | >> + ASPEED_I2CD_TIME_THDSTA_MASK | >> + ASPEED_I2CD_TIME_TACST_MASK); >> + clk_reg_val |= (divisor & ASPEED_I2CD_TIME_BASE_DIVISOR_MASK) >> + | ((clk_high << ASPEED_I2CD_TIME_SCL_HIGH_SHIFT) >> + & ASPEED_I2CD_TIME_SCL_HIGH_MASK) >> + | ((clk_low << ASPEED_I2CD_TIME_SCL_LOW_SHIFT) >> + & ASPEED_I2CD_TIME_SCL_LOW_MASK); >> + writel(clk_reg_val, bus->base + ASPEED_I2C_AC_TIMING_REG1); >> + writel(ASPEED_NO_TIMEOUT_CTRL, bus->base + ASPEED_I2C_AC_TIMING_REG2); >> + >> + return 0; >> +} >> + >> /* precondition: bus.lock has been acquired. */ >> static int aspeed_i2c_init(struct aspeed_i2c_bus *bus, >> struct platform_device *pdev) >> @@ -908,7 +958,10 @@ static int aspeed_i2c_init(struct aspeed_i2c_bus *bus, >> /* Disable everything. */ >> writel(0, bus->base + ASPEED_I2C_FUN_CTRL_REG); >> >> - ret = aspeed_i2c_init_clk(bus); >> + if (of_property_read_bool(pdev->dev.of_node, "aspeed,i2c-manual-clk")) >> + ret = aspeed_i2c_manual_clk_setup(bus); >> + else >> + ret = aspeed_i2c_init_clk(bus); >> if (ret < 0) >> return ret; >> >> -- >> 2.17.1 >>
diff --git a/drivers/i2c/busses/i2c-aspeed.c b/drivers/i2c/busses/i2c-aspeed.c index 67e8b97c0c95..1f4b5c4b5bf4 100644 --- a/drivers/i2c/busses/i2c-aspeed.c +++ b/drivers/i2c/busses/i2c-aspeed.c @@ -898,6 +898,56 @@ static int aspeed_i2c_init_clk(struct aspeed_i2c_bus *bus) return 0; } +/* precondition: bus.lock has been acquired. */ +static int aspeed_i2c_manual_clk_setup(struct aspeed_i2c_bus *bus) +{ + u32 divisor, clk_high, clk_low, clk_reg_val; + + if (device_property_read_u32(bus->dev, "aspeed,i2c-base-clk-div", + &divisor) != 0) { + dev_err(bus->dev, "Could not read aspeed,i2c-base-clk-div\n"); + return -EINVAL; + } else if (divisor > ASPEED_I2CD_TIME_BASE_DIVISOR_MASK) { + dev_err(bus->dev, "Invalid aspeed,i2c-base-clk-div: %u\n", + divisor); + return -EINVAL; + } + + if (device_property_read_u32(bus->dev, "aspeed,i2c-clk-high-cycle", + &clk_high) != 0) { + dev_err(bus->dev, "Could not read aspeed,i2c-clk-high-cycle\n"); + return -EINVAL; + } else if (clk_high > ASPEED_I2CD_TIME_SCL_REG_MAX) { + dev_err(bus->dev, "Invalid aspeed,i2c-clk-high-cycle: %u\n", + clk_high); + return -EINVAL; + } + + if (device_property_read_u32(bus->dev, "aspeed,i2c-clk-low-cycle", + &clk_low) != 0) { + dev_err(bus->dev, "Could not read aspeed,i2c-clk-low-cycle\n"); + return -EINVAL; + } else if (clk_low > ASPEED_I2CD_TIME_SCL_REG_MAX) { + dev_err(bus->dev, "Invalid aspeed,i2c-clk-low-cycle: %u\n", + clk_low); + return -EINVAL; + } + + clk_reg_val = readl(bus->base + ASPEED_I2C_AC_TIMING_REG1); + clk_reg_val &= (ASPEED_I2CD_TIME_TBUF_MASK | + ASPEED_I2CD_TIME_THDSTA_MASK | + ASPEED_I2CD_TIME_TACST_MASK); + clk_reg_val |= (divisor & ASPEED_I2CD_TIME_BASE_DIVISOR_MASK) + | ((clk_high << ASPEED_I2CD_TIME_SCL_HIGH_SHIFT) + & ASPEED_I2CD_TIME_SCL_HIGH_MASK) + | ((clk_low << ASPEED_I2CD_TIME_SCL_LOW_SHIFT) + & ASPEED_I2CD_TIME_SCL_LOW_MASK); + writel(clk_reg_val, bus->base + ASPEED_I2C_AC_TIMING_REG1); + writel(ASPEED_NO_TIMEOUT_CTRL, bus->base + ASPEED_I2C_AC_TIMING_REG2); + + return 0; +} + /* precondition: bus.lock has been acquired. */ static int aspeed_i2c_init(struct aspeed_i2c_bus *bus, struct platform_device *pdev) @@ -908,7 +958,10 @@ static int aspeed_i2c_init(struct aspeed_i2c_bus *bus, /* Disable everything. */ writel(0, bus->base + ASPEED_I2C_FUN_CTRL_REG); - ret = aspeed_i2c_init_clk(bus); + if (of_property_read_bool(pdev->dev.of_node, "aspeed,i2c-manual-clk")) + ret = aspeed_i2c_manual_clk_setup(bus); + else + ret = aspeed_i2c_init_clk(bus); if (ret < 0) return ret;