linux-kernel - Re: [PATCH 06/13] scpi: add priv_scpi

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Message-ID: <a0c9c4bc-cd83-c2e7-bfab-b8d24c886349@baylibre.com>
Date:   Tue, 23 Aug 2016 10:22:25 +0200
From:   Neil Armstrong <narmstrong@...libre.com>
To:     Sudeep Holla <sudeep.holla@....com>,
        linux-arm-kernel@...ts.infradead.org, linux-kernel@...r.kernel.org
Cc:     linux-amlogic@...ts.infradead.org, khilman@...libre.com,
        heiko@...ech.de, wxt@...k-chips.com, frank.wang@...k-chips.com
Subject: Re: [PATCH 06/13] scpi: add priv_scpi_ops and fill legacy structure

On 08/19/2016 06:39 PM, Sudeep Holla wrote:
> 
> 
> On 18/08/16 11:10, Neil Armstrong wrote:
>> In order to use the legacy functions variants, add a new priv_scpi_ops
>> structure that will contain the internal alterne functions and then use these
>> alternate call in the probe function.
>>
>> Signed-off-by: Neil Armstrong <narmstrong@...libre.com>
>> ---
>>  drivers/firmware/arm_scpi.c | 68 ++++++++++++++++++++++++++++++++++++++++++---
>>  1 file changed, 64 insertions(+), 4 deletions(-)
>>
>> diff --git a/drivers/firmware/arm_scpi.c b/drivers/firmware/arm_scpi.c
>> index b0d911b..3fe39fe 100644
>> --- a/drivers/firmware/arm_scpi.c
>> +++ b/drivers/firmware/arm_scpi.c
>> @@ -213,6 +213,7 @@ struct scpi_drvinfo {
>>      struct scpi_ops *scpi_ops;
>>      struct scpi_chan *channels;
>>      struct scpi_dvfs_info *dvfs[MAX_DVFS_DOMAINS];
>> +    const struct priv_scpi_ops *ops;
>>  };
>>
>>  /*
>> @@ -299,6 +300,17 @@ struct dev_pstate_set {
>>      u8 pstate;
>>  } __packed;
>>
>> +struct priv_scpi_ops {
>> +    /* Internal Specific Ops */
>> +    void (*handle_remote_msg)(struct mbox_client *c, void *msg);
>> +    void (*tx_prepare)(struct mbox_client *c, void *msg);
>> +    /* Message Specific Ops */
>> +    int (*init_versions)(struct scpi_drvinfo *info);
>> +    int (*dvfs_get_info)(u8 domain, struct dvfs_info *buf);
>> +    /* System wide Ops */
>> +    struct scpi_ops *scpi_ops;
>> +};
>> +
> 
> 
> I fail to understand the need for this. Can you please explain the issue
> you would face without this ?
> 
>>  static struct scpi_drvinfo *scpi_info;
>>
>>  static int scpi_linux_errmap[SCPI_ERR_MAX] = {
>> @@ -695,9 +707,12 @@ static struct scpi_dvfs_info *scpi_dvfs_get_info(u8 domain)
>>      if (scpi_info->dvfs[domain])    /* data already populated */
>>          return scpi_info->dvfs[domain];
>>
>> -    ret = scpi_send_message(SCPI_CMD_GET_DVFS_INFO, &domain, sizeof(domain),
>> +    if (scpi_info->ops && scpi_info->ops->dvfs_get_info)
>> +        ret = scpi_info->ops->dvfs_get_info(domain, &buf);
>> +    else
>> +        ret = scpi_send_message(SCPI_CMD_GET_DVFS_INFO,
>> +                    &domain, sizeof(domain),
>>                  &buf, sizeof(buf));
>> -
>>      if (ret)
>>          return ERR_PTR(ret);
>>
>> @@ -855,6 +870,22 @@ static struct scpi_ops scpi_ops = {
>>      .vendor_send_message = scpi_ext_send_message,
>>  };
>>
>> +static struct scpi_ops legacy_scpi_ops = {
>> +    .get_version = scpi_get_version,
>> +    .clk_get_range = NULL,
>> +    .clk_get_val = legacy_scpi_clk_get_val,
>> +    .clk_set_val = legacy_scpi_clk_set_val,
>> +    .dvfs_get_idx = legacy_scpi_dvfs_get_idx,
>> +    .dvfs_set_idx = legacy_scpi_dvfs_set_idx,
>> +    .dvfs_get_info = scpi_dvfs_get_info,
>> +    .sensor_get_capability = legacy_scpi_sensor_get_capability,
>> +    .sensor_get_info = legacy_scpi_sensor_get_info,
>> +    .sensor_get_value = legacy_scpi_sensor_get_value,
>> +    .device_get_power_state = NULL,
>> +    .device_set_power_state = NULL,
>> +    .vendor_send_message = legacy_scpi_send_message,
> 
> I think we need not have this at all if you follow the suggestion I had
> in the previous patch. Try and let's see how it would look.

If you confirm you want the if/else as said in patch 4.

But clk_get_range, device_get/set_power_state are not available in legacy,
I think we should still have this alternate structure.

>> +};
>> +
>>  struct scpi_ops *get_scpi_ops(void)
>>  {
>>      return scpi_info ? scpi_info->scpi_ops : NULL;
>> @@ -972,8 +1003,17 @@ static int scpi_alloc_xfer_list(struct device *dev, struct scpi_chan *ch)
>>      return 0;
>>  }
>>
>> +static const struct priv_scpi_ops scpi_legacy_ops = {
>> +    .handle_remote_msg = legacy_scpi_handle_remote_msg,
>> +    .tx_prepare = legacy_scpi_tx_prepare,
>> +    .init_versions = legacy_scpi_init_versions,
>> +    .dvfs_get_info = legacy_scpi_dvfs_get_info,
>> +    .scpi_ops = &legacy_scpi_ops,
>> +};
>> +
> 
> Ditto, can go away.
> 

Yes, in the if/else is_legacy variant this should go away.

Thanks,
Neil