Re: [PATCH 3/3] hwmon: g672: add support for g761

Guenter Roeck
2024-05-25T14:29:58Z

On 5/25/24 03:29, Christian Marangi wrote:
> Add support for g761 PWM Fan Controller.
>
> The g761 is a copy of the g763 with the only difference of supporting
> and internal clock. This can be configured with the gmt,internal-clock
> property and in such case clock handling is skipped.
>

Do you happen to have a datasheet ? The datasheet is not available from GMT,
making it impossible to validate the changes.

> Signed-off-by: Christian Marangi <ansuelsmth@gmail.com>
> ---
> drivers/hwmon/g762.c | 23 ++++++++++++++++++++---
> 1 file changed, 20 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/hwmon/g762.c b/drivers/hwmon/g762.c
> index af1228708e25..1629a3141c11 100644
> --- a/drivers/hwmon/g762.c
> +++ b/drivers/hwmon/g762.c
> @@ -69,6 +69,7 @@ enum g762_regs {
> #define G762_REG_FAN_CMD1_PWM_POLARITY 0x02 /* PWM polarity */
> #define G762_REG_FAN_CMD1_PULSE_PER_REV 0x01 /* pulse per fan revolution */
>
> +#define G761_REG_FAN_CMD2_FAN_CLOCK 0x20 /* choose internal clock*/
> #define G762_REG_FAN_CMD2_GEAR_MODE_1 0x08 /* fan gear mode */
> #define G762_REG_FAN_CMD2_GEAR_MODE_0 0x04
> #define G762_REG_FAN_CMD2_FAN_STARTV_1 0x02 /* fan startup voltage */
> @@ -115,6 +116,7 @@ enum g762_regs {
>
> struct g762_data {
> struct i2c_client *client;
> + bool internal_clock;
> struct clk *clk;
>
> /* update mutex */
> @@ -566,6 +568,7 @@ static int do_set_fan_startv(struct device *dev, unsigned long val)
>
> #ifdef CONFIG_OF
> static const struct of_device_id g762_dt_match[] = {
> + { .compatible = "gmt,g761" },
> { .compatible = "gmt,g762" },
> { .compatible = "gmt,g763" },
> { },
> @@ -597,6 +600,16 @@ static int g762_of_clock_enable(struct i2c_client *client)
> if (!client->dev.of_node)
> return 0;
>
> + data = i2c_get_clientdata(client);
> +
> + /* Skip CLK detection and handling if we use internal clock */
> + data->internal_clock = of_property_read_bool(client->dev.of_node,
> + "gmt,internal-clock");
> + if (data->internal_clock) {
> + do_set_clk_freq(&client->dev, 32768); > + return 0;
> + }:
> +
> clk = of_clk_get(client->dev.of_node, 0);
> if (IS_ERR(clk)) {
> dev_err(&client->dev, "failed to get clock\n");
> @@ -616,7 +629,6 @@ static int g762_of_clock_enable(struct i2c_client *client)
> goto clk_unprep;
> }
>
> - data = i2c_get_clientdata(client);
> data->clk = clk;
>
> ret = devm_add_action(&client->dev, g762_of_clock_disable, data);
> @@ -1029,12 +1041,17 @@ static inline int g762_fan_init(struct device *dev)
> if (IS_ERR(data))
> return PTR_ERR(data);
>
> + if (data->internal_clock)
> + data->fan_cmd2 |= G761_REG_FAN_CMD2_FAN_CLOCK;
> +

This and the property must only be accepted for G761.

> data->fan_cmd1 |= G762_REG_FAN_CMD1_DET_FAN_FAIL;
> data->fan_cmd1 |= G762_REG_FAN_CMD1_DET_FAN_OOC;
> data->valid = false;
>
> - return i2c_smbus_write_byte_data(data->client, G762_REG_FAN_CMD1,
> - data->fan_cmd1);
> + return (i2c_smbus_write_byte_data(data->client, G762_REG_FAN_CMD1,
> + data->fan_cmd1) |
> + i2c_smbus_write_byte_data(data->client, G762_REG_FAN_CMD2,
> + data->fan_cmd2));

This is wrong. It would logically combine error codes, and execute
the second write even after the first failed.

Guenter

> }
>
> static int g762_probe(struct i2c_client *client)