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    SubjectRe: [PATCH v2 1/8] [PATCH 1/8] drivers/peci: Add support for PECI bus driver core
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    On 2/21/2018 1:51 PM, Andrew Lunn wrote:
    >>> Is there a real need to do transfers in atomic context, or with
    >>> interrupts disabled?
    >>>
    >>
    >> Actually, no. Generally, this function will be called in sleep-able context
    >> so this code is for an exceptional case handling.
    >>
    >> I'll rewrite this code like below:
    >> if (in_atomic() || irqs_disabled()) {
    >> dev_dbg(&adapter->dev,
    >> "xfer in non-sleepable context is not supported\n");
    >> return -EWOULDBLOCK;
    >> }
    >
    > I would not even do that. Just add a call to
    > might_sleep(). CONFIG_DEBUG_ATOMIC_SLEEP will then find bad calls.
    >

    Thanks for the suggestion. I've learned one thing. :)

    >>>> +static int peci_ioctl_get_temp(struct peci_adapter *adapter, void *vmsg)
    >>>> +{
    >>>> + struct peci_get_temp_msg *umsg = vmsg;
    >>>> + struct peci_xfer_msg msg;
    >>>> + int rc;
    >>>> +
    >>>
    >>> Is this getting the temperature?
    >>>
    >>
    >> Yes, this is getting the 'die' temperature of a processor package.
    >
    > So the hwmon driver provides this. No need to have both.
    >

    This this common API in core driver of PECI bus. The hwmon is also uses
    it through peci_command call.

    >>>> +static long peci_ioctl(struct file *file, unsigned int iocmd, unsigned long arg)
    >>>> +{
    >>>> + struct peci_adapter *adapter = file->private_data;
    >>>> + void __user *argp = (void __user *)arg;
    >>>> + unsigned int msg_len;
    >>>> + enum peci_cmd cmd;
    >>>> + u8 *msg;
    >>>> + int rc = 0;
    >>>> +
    >>>> + dev_dbg(&adapter->dev, "ioctl, cmd=0x%x, arg=0x%lx\n", iocmd, arg);
    >>>> +
    >>>> + switch (iocmd) {
    >>>> + case PECI_IOC_PING:
    >>>> + case PECI_IOC_GET_DIB:
    >>>> + case PECI_IOC_GET_TEMP:
    >>>> + case PECI_IOC_RD_PKG_CFG:
    >>>> + case PECI_IOC_WR_PKG_CFG:
    >>>> + case PECI_IOC_RD_IA_MSR:
    >>>> + case PECI_IOC_RD_PCI_CFG:
    >>>> + case PECI_IOC_RD_PCI_CFG_LOCAL:
    >>>> + case PECI_IOC_WR_PCI_CFG_LOCAL:
    >>>> + cmd = _IOC_TYPE(iocmd) - PECI_IOC_BASE;
    >>>> + msg_len = _IOC_SIZE(iocmd);
    >>>> + break;
    >>>
    >>> Adding new ioctl calls is pretty frowned up. Can you export this info
    >>> via /sysfs?
    >>>
    >>
    >> Most of these are not simple IOs so ioctl is better suited, I think.
    >
    > Lets see what other reviewers say, but i think ioctls are
    > wrong.
    >
    > Andrew
    >

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