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

Christian Marangi
2024-05-25T14:33:50Z

On Sat, May 25, 2024 at 07:29:55AM -0700, Guenter Roeck wrote:
> 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.
>

No datasheet, online there is only the first page that describe the
features.

This internal clock feature is the only difference to g763 and is
present in a downstream driver from a Asus ipq807x router.

I verified that all the regs match.

> > 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.
>

Yes you are right. I limit this only in Documentation but as a failsafe
I should also verify this here. Will do in V2.

> > 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.
>

Ok will change the thing.

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

--
Ansuel