Hi Chunfeng,
On Mon, Mar 26, 2018 at 5:37 AM, Chunfeng Yun <chunfeng.yun@xxxxxxxxxxxx> wrote:
> On Sat, 2018-03-24 at 15:21 +0100, Martin Blumenstingl wrote:
>> Before this patch usb_phy_roothub_init served two purposes (from a
>> caller's point of view - like hcd.c):
>> - parsing the PHYs and allocating the list entries
>> - calling phy_init on each list entry
>>
>> While this worked so far it has one disadvantage: if we need to call
>> phy_init for each PHY instance then the existing code cannot be re-used.
>> Solve this by splitting off usb_phy_roothub_alloc which only parses the
>> PHYs and allocates the list entries.
>> usb_phy_roothub_init then gets a struct usb_phy_roothub and only calls
>> phy_init on each PHY instance (along with the corresponding cleanup if
>> that failed somewhere).
>>
>> This is a preparation step for adding proper suspend support for some
>> hardware that requires phy_exit to be called during suspend and phy_init
>> to be called during resume.
>>
>> Signed-off-by: Martin Blumenstingl <martin.blumenstingl@xxxxxxxxxxxxxx>
>> ---
>> drivers/usb/core/hcd.c | 10 +++++++---
>> drivers/usb/core/phy.c | 51 +++++++++++++++++++++++++-------------------------
>> drivers/usb/core/phy.h | 4 +++-
>> 3 files changed, 35 insertions(+), 30 deletions(-)
>>
>> diff --git a/drivers/usb/core/hcd.c b/drivers/usb/core/hcd.c
>> index 777036ae6367..15b0418e3b6a 100644
>> --- a/drivers/usb/core/hcd.c
>> +++ b/drivers/usb/core/hcd.c
>> @@ -2758,12 +2758,16 @@ int usb_add_hcd(struct usb_hcd *hcd,
>> }
>>
>> if (!hcd->skip_phy_initialization && usb_hcd_is_primary_hcd(hcd)) {
>> - hcd->phy_roothub = usb_phy_roothub_init(hcd->self.sysdev);
>> + hcd->phy_roothub = usb_phy_roothub_alloc(hcd->self.sysdev);
>> if (IS_ERR(hcd->phy_roothub)) {
>> retval = PTR_ERR(hcd->phy_roothub);
>> - goto err_phy_roothub_init;
>> + goto err_phy_roothub_alloc;
>> }
>>
>> + retval = usb_phy_roothub_init(hcd->phy_roothub);
>> + if (retval)
>> + goto err_phy_roothub_alloc;
>> +
>> retval = usb_phy_roothub_power_on(hcd->phy_roothub);
>> if (retval)
>> goto err_usb_phy_roothub_power_on;
>> @@ -2936,7 +2940,7 @@ int usb_add_hcd(struct usb_hcd *hcd,
>> usb_phy_roothub_power_off(hcd->phy_roothub);
>> err_usb_phy_roothub_power_on:
>> usb_phy_roothub_exit(hcd->phy_roothub);
>> -err_phy_roothub_init:
>> +err_phy_roothub_alloc:
>> if (hcd->remove_phy && hcd->usb_phy) {
>> usb_phy_shutdown(hcd->usb_phy);
>> usb_put_phy(hcd->usb_phy);
>> diff --git a/drivers/usb/core/phy.c b/drivers/usb/core/phy.c
>> index f19aaa3c899c..d1861c5a74de 100644
>> --- a/drivers/usb/core/phy.c
>> +++ b/drivers/usb/core/phy.c
>> @@ -19,19 +19,6 @@ struct usb_phy_roothub {
>> struct list_head list;
>> };
>>
>> -static struct usb_phy_roothub *usb_phy_roothub_alloc(struct device *dev)
>> -{
>> - struct usb_phy_roothub *roothub_entry;
>> -
>> - roothub_entry = devm_kzalloc(dev, sizeof(*roothub_entry), GFP_KERNEL);
>> - if (!roothub_entry)
>> - return ERR_PTR(-ENOMEM);
>> -
>> - INIT_LIST_HEAD(&roothub_entry->list);
>> -
>> - return roothub_entry;
>> -}
>> -
>> static int usb_phy_roothub_add_phy(struct device *dev, int index,
>> struct list_head *list)
>> {
>> @@ -45,9 +32,9 @@ static int usb_phy_roothub_add_phy(struct device *dev, int index,
>> return PTR_ERR(phy);
>> }
>
>>
>> - roothub_entry = usb_phy_roothub_alloc(dev);
>> - if (IS_ERR(roothub_entry))
>> - return PTR_ERR(roothub_entry);
>> + roothub_entry = devm_kzalloc(dev, sizeof(*roothub_entry), GFP_KERNEL);
>> + if (!roothub_entry)
>> + return -ENOMEM;
>>
>> roothub_entry->phy = phy;
>>
>> @@ -56,11 +43,9 @@ static int usb_phy_roothub_add_phy(struct device *dev, int index,
>> return 0;
>> }
>>
>> -struct usb_phy_roothub *usb_phy_roothub_init(struct device *dev)
>> +struct usb_phy_roothub *usb_phy_roothub_alloc(struct device *dev)
>> {
>> struct usb_phy_roothub *phy_roothub;
>> - struct usb_phy_roothub *roothub_entry;
>> - struct list_head *head;
>> int i, num_phys, err;
>>
>> num_phys = of_count_phandle_with_args(dev->of_node, "phys",
>> @@ -68,16 +53,31 @@ struct usb_phy_roothub *usb_phy_roothub_init(struct device *dev)
>> if (num_phys <= 0)
>> return NULL;
>>
>> - phy_roothub = usb_phy_roothub_alloc(dev);
>> - if (IS_ERR(phy_roothub))
>> - return phy_roothub;
>> + phy_roothub = devm_kzalloc(dev, sizeof(*phy_roothub), GFP_KERNEL);
>> + if (!phy_roothub)
>> + return ERR_PTR(-ENOMEM);
>> +
>> + INIT_LIST_HEAD(&phy_roothub->list);
>>
>> for (i = 0; i < num_phys; i++) {
>> err = usb_phy_roothub_add_phy(dev, i, &phy_roothub->list);
> BTW:
>
> static int usb_phy_roothub_add_phy(struct device *dev, int index,
> struct list_head *list)
> {
> struct usb_phy_roothub *roothub_entry;
> struct phy *phy = devm_of_phy_get_by_index(dev, dev->of_node,
> index);
>
> if (IS_ERR_OR_NULL(phy)) {
> if (!phy || PTR_ERR(phy) == -ENODEV)
> return 0;
> else
> return PTR_ERR(phy);
> }
>
> changed as:
> if (IS_ERR(phy))
> return PTR_ERR(phy);
>
> The checking of return code of devm_of_phy_get_by_index() called by
> usb_phy_roothub_add_phy() need be fixed? because it should exist for
> index @i.
good catch - thank you!
I think (but I don't remember exactly) my idea was to catch the case
where CONFIG_GENERIC_PHY was disabled. however, in that case the PHY
framework returns ERR_PTR(-ENOSYS);
let me know if I should send a patch for this issue or if you want to
send a patch yourself
however, I'd suggest waiting until this RFC is finished/merged because
this issue already exist in the code before this series
>> if (err)
>> - goto err_out;
>> + return ERR_PTR(err);
>> }
>>
>> + return phy_roothub;
>> +}
>> +EXPORT_SYMBOL_GPL(usb_phy_roothub_alloc);
>> +
>> +int usb_phy_roothub_init(struct usb_phy_roothub *phy_roothub)
>> +{
>> + struct usb_phy_roothub *roothub_entry;
>> + struct list_head *head;
>> + int err;
>> +
>> + if (!phy_roothub)
>> + return 0;
>> +
>> head = &phy_roothub->list;
>>
>> list_for_each_entry(roothub_entry, head, list) {
>> @@ -86,14 +86,13 @@ struct usb_phy_roothub *usb_phy_roothub_init(struct device *dev)
>> goto err_exit_phys;
>> }
>>
>> - return phy_roothub;
>> + return 0;
>>
>> err_exit_phys:
>> list_for_each_entry_continue_reverse(roothub_entry, head, list)
>> phy_exit(roothub_entry->phy);
>>
>> -err_out:
>> - return ERR_PTR(err);
>> + return err;
>> }
>> EXPORT_SYMBOL_GPL(usb_phy_roothub_init);
>>
>> diff --git a/drivers/usb/core/phy.h b/drivers/usb/core/phy.h
>> index 6fde59bfbff8..eb31253201ad 100644
>> --- a/drivers/usb/core/phy.h
>> +++ b/drivers/usb/core/phy.h
>> @@ -1,6 +1,8 @@
>> struct usb_phy_roothub;
>>
>> -struct usb_phy_roothub *usb_phy_roothub_init(struct device *dev);
>> +struct usb_phy_roothub *usb_phy_roothub_alloc(struct device *dev);
>> +
>> +int usb_phy_roothub_init(struct usb_phy_roothub *phy_roothub);
>> int usb_phy_roothub_exit(struct usb_phy_roothub *phy_roothub);
>>
>> int usb_phy_roothub_power_on(struct usb_phy_roothub *phy_roothub);
>
>
Regards
Martin
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