2022-05-31 22:30:51

by Potin Lai

[permalink] [raw]
Subject: [PATCH 1/1] aspeed: i2c: add manual clock setup feature

From: Porin Lai <[email protected]>

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)

Signed-off-by: Potin Lai <[email protected]>
---
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



2022-06-01 15:00:01

by Potin Lai

[permalink] [raw]
Subject: Re: [PATCH 1/1] aspeed: i2c: add manual clock setup feature


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 <[email protected]>
>>
>> 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 <[email protected]>
>> ---
>> 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
>>

2022-06-01 20:59:49

by Patrick Williams

[permalink] [raw]
Subject: Re: [PATCH 1/1] aspeed: i2c: add manual clock setup feature

On Mon, May 30, 2022 at 07:40:56PM +0800, Potin Lai wrote:
> From: Porin Lai <[email protected]>
>
> 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 ?

>
> Signed-off-by: Potin Lai <[email protected]>
> ---
> 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
>

--
Patrick Williams


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