Re: [PATCH v5 2/2] phy: rockchip-inno-usb2: add a new driver for Rockchip usb2phy

[Frank Wang <frank.wang@rock-chips.com>]

Hi Heiko,

On 2016/6/14 21:27, Heiko Stübner wrote:
> Am Montag, 13. Juni 2016, 10:10:10 schrieb Frank Wang:
>> The newer SoCs (rk3366, rk3399) take a different usb-phy IP block
>> than rk3288 and before, and most of phy-related registers are also
>> different from the past, so a new phy driver is required necessarily.
>>
>> Signed-off-by: Frank Wang <frank.wang@rock-chips.com>
>> ---
>>
>> Changes in v5:
>>   - Added 'reg' in the data block to match the different phy-blocks in dt.
>>
>> Changes in v4:
>>   - Removed some processes related to 'vbus_host-supply'.
>>
>> Changes in v3:
>>   - Resolved the mapping defect between fixed value in driver and the
>> property in devicetree.
>>   - Optimized 480m output clock register function.
>>   - Code cleanup.
>>
>> Changes in v2:
>>   - Changed vbus_host operation from gpio to regulator in *_probe.
>>   - Improved the fault treatment relate to 480m clock register.
>>   - Cleaned up some meaningless codes in *_clk480m_disable.
>>   - made more clear the comment of *_sm_work.
>>
>>   drivers/phy/Kconfig                  |    7 +
>>   drivers/phy/Makefile                 |    1 +
>>   drivers/phy/phy-rockchip-inno-usb2.c |  645
>> ++++++++++++++++++++++++++++++++++ 3 files changed, 653 insertions(+)
>>   
>> [...]
>>
>> +
>> +static int rockchip_usb2phy_exit(struct phy *phy)
>> +{
>> +	struct rockchip_usb2phy_port *rport = phy_get_drvdata(phy);
>> +
> 	if (!rport->port_cfg)
> 		return 0;
>
>> +	if (rport->port_id == USB2PHY_PORT_HOST)
>> +		cancel_delayed_work_sync(&rport->sm_work);
>> +
> you will also need to resume the port here, if it is suspended at this point,
> as phy_power_off gets called after phy_exit and would probably produce clk
> enable/disable mismatches otherwise.
>

Hmm, from my personal point of view, when canceling sm_work here, it may 
not cause the port goes to suspend, isn't it? besides, clk only prepared 
in *_usb2phy_resume(), and unprepared in *_usb2phy_suspend(), so if we 
resume port here,  the prepare_count of clk will be increased again, I 
am afraid this is not correct, and am I wrong? would you like to tell me 
more details?

>> +	return 0;
>> +}
>>
>> [...]
>>
>> +static int rockchip_usb2phy_probe(struct platform_device *pdev)
>> +{
>> +	struct device *dev = &pdev->dev;
>> +	struct device_node *np = dev->of_node;
>> +	struct device_node *child_np;
>>
>> [...]
>>
>> +	index = 0;
>> +	for_each_available_child_of_node(np, child_np) {
>> +		struct rockchip_usb2phy_port *rport = &rphy->ports[index];
>> +		struct phy *phy;
>> +
>> +		phy = devm_phy_create(dev, child_np, &rockchip_usb2phy_ops);
>> +		if (IS_ERR(phy)) {
>> +			dev_err(dev, "failed to create phy\n");
>> +			ret = PTR_ERR(phy);
>> +			goto put_child;
>> +		}
>> +
>> +		rport->phy = phy;
> 	phy_set_drvdata(rport->phy, rport);
>
>> +
>> +		/* initialize otg/host port separately */
>> +		if (!of_node_cmp(child_np->name, "host-port")) {
>> +			ret = rockchip_usb2phy_host_port_init(rphy, rport,
>> +							      child_np);
>> +			if (ret)
>> +				goto put_child;
>> +		}
>> +
>> +		phy_set_drvdata(rport->phy, rport);
> move this to the location above to prevent null-pointer dereferences with
> devices plugged in on boot.

OK, I will fix it.

>
> I've tested this a bit on a rk3036 (which is lacking the disconnect-detection
> it seems), so in general (apart from the stuff mentioned above) this looks
> nice now. So with the stuff above fixed:
>
> Reviewed-by: Heiko Stuebner <heiko@sntech.de>
> Tested-by: Heiko Stuebner <heiko@sntech.de>

BR.
Frank