Re: [PATCH v2] hwmon: (pmbus/ibm-cffps) max_power_out swap changes

From: Guenter Roeck
Date: Sat Oct 02 2021 - 07:40:58 EST


On Tue, Sep 28, 2021 at 08:50:51PM +0000, Brandon Wyman wrote:
> The bytes for max_power_out from the ibm-cffps devices differ in byte
> order for some power supplies.
>
> The Witherspoon power supply returns the bytes in MSB/LSB order.
>
> The Rainier power supply returns the bytes in LSB/MSB order.
>
> The Witherspoon power supply uses version cffps1. The Rainier power
> supply should use version cffps2. If version is cffps1, swap the bytes
> before output to max_power_out.
>
> Tested:
> Witherspoon before: 3148. Witherspoon after: 3148.
> Rainier before: 53255. Rainier after: 2000.
>
> Signed-off-by: Brandon Wyman <bjwyman@xxxxxxxxx>
> Reviewed-by: Eddie James <eajames@xxxxxxxxxxxxx>

Applied, though ...

> ---
> drivers/hwmon/pmbus/ibm-cffps.c | 10 ++++++++--
> 1 file changed, 8 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/hwmon/pmbus/ibm-cffps.c b/drivers/hwmon/pmbus/ibm-cffps.c
> index df712ce4b164..79bfcd2749a6 100644
> --- a/drivers/hwmon/pmbus/ibm-cffps.c
> +++ b/drivers/hwmon/pmbus/ibm-cffps.c
> @@ -171,8 +171,14 @@ static ssize_t ibm_cffps_debugfs_read(struct file *file, char __user *buf,
> cmd = CFFPS_SN_CMD;
> break;
> case CFFPS_DEBUGFS_MAX_POWER_OUT:
> - rc = i2c_smbus_read_word_swapped(psu->client,
> - CFFPS_MAX_POWER_OUT_CMD);
> + if (cffps1 == psu->version) {

The yoda programming replaced I did.

> + rc = i2c_smbus_read_word_swapped(psu->client,
> + CFFPS_MAX_POWER_OUT_CMD);
> + } else {
> + rc = i2c_smbus_read_word_data(psu->client,
> + CFFPS_MAX_POWER_OUT_CMD);
> + }
> +
> if (rc < 0)
> return rc;
>