Subject: [PATCH] usb: gadget: at91_udc: add usb_clk for transition to common clk framework

From: [email-masked] (boris brezillon)
Date: Mon, 12 Aug 2013 22:42:43 +0200

Hello Nicolas,

On 12/08/2013 15:52, Nicolas Ferre wrote:
> On 01/08/2013 08:18, Boris BREZILLON :
>> The AT91 PMC (Power Management Controller) provides an USB clock used by
>> USB Full Speed host (ohci) and USB Full Speed device (udc).
>> The usb drivers (ohci and udc) must configure this clock to 48Mhz.
>> This configuration was formely done in mach-at91/clock.c, but this
>> implementation will be removed when moving to common clk framework.
>>
>> This patch adds support for usb clock retrieval and configuration, 
>> and is
>> backward compatible with the current at91 clk implementation (if usb clk
>> is not found, it does not configure/enable it).
>>
>> Signed-off-by: Boris BREZILLON <[email-masked]>
>
> Acked-by: Nicolas Ferre <[email-masked]>
>
Is there a reason you acked this version but not the 3rd one 
(https://lkml.org/lkml/2013/8/2/102).
>> ---
>>   drivers/usb/gadget/at91_udc.c |   17 ++++++++++++++++-
>>   drivers/usb/gadget/at91_udc.h |    2 +-
>>   2 files changed, 17 insertions(+), 2 deletions(-)
>>
>> diff --git a/drivers/usb/gadget/at91_udc.c 
>> b/drivers/usb/gadget/at91_udc.c
>> index fce8e4e..ae06585 100644
>> --- a/drivers/usb/gadget/at91_udc.c
>> +++ b/drivers/usb/gadget/at91_udc.c
>> @@ -870,6 +870,11 @@ static void clk_on(struct at91_udc *udc)
>>       if (udc->clocked)
>>           return;
>>       udc->clocked = 1;
>> +
>> +    if (!IS_ERR(udc->uclk)) {
>> +        clk_set_rate(udc->uclk, 48000000);
>> +        clk_prepare_enable(udc->uclk);
>> +    }
>>       clk_prepare_enable(udc->iclk);
>>       clk_prepare_enable(udc->fclk);
>>   }
>> @@ -882,6 +887,8 @@ static void clk_off(struct at91_udc *udc)
>>       udc->gadget.speed = USB_SPEED_UNKNOWN;
>>       clk_disable_unprepare(udc->fclk);
>>       clk_disable_unprepare(udc->iclk);
>> +    if (!IS_ERR(udc->uclk))
>> +        clk_disable_unprepare(udc->uclk);
>>   }
>>
>>   /*
>> @@ -1774,10 +1781,10 @@ static int at91udc_probe(struct 
>> platform_device *pdev)
>>       /* get interface and function clocks */
>>       udc->iclk = clk_get(dev, "udc_clk");
>>       udc->fclk = clk_get(dev, "udpck");
>> +    udc->uclk = clk_get(dev, "usb_clk");
>>       if (IS_ERR(udc->iclk) || IS_ERR(udc->fclk)) {
>>           DBG("clocks missing\n");
>>           retval = -ENODEV;
>> -        /* NOTE: we "know" here that refcounts on these are NOPs */
>>           goto fail1;
>>       }
>>
>> @@ -1851,6 +1858,12 @@ fail3:
>>   fail2:
>>       free_irq(udc->udp_irq, udc);
>>   fail1:
>> +    if (!IS_ERR(udc->uclk))
>> +        clk_put(udc->uclk);
>> +    if (!IS_ERR(udc->fclk))
>> +        clk_put(udc->fclk);
>> +    if (!IS_ERR(udc->iclk))
>> +        clk_put(udc->iclk);
>>       iounmap(udc->udp_baseaddr);
>>   fail0a:
>>       if (cpu_is_at91rm9200())
>> @@ -1894,6 +1907,8 @@ static int __exit at91udc_remove(struct 
>> platform_device *pdev)
>>
>>       clk_put(udc->iclk);
>>       clk_put(udc->fclk);
>> +    if (!IS_ERR(udc->uclk))
>> +        clk_put(udc->uclk);
>>
>>       return 0;
>>   }
>> diff --git a/drivers/usb/gadget/at91_udc.h 
>> b/drivers/usb/gadget/at91_udc.h
>> index e647d1c..0175246 100644
>> --- a/drivers/usb/gadget/at91_udc.h
>> +++ b/drivers/usb/gadget/at91_udc.h
>> @@ -126,7 +126,7 @@ struct at91_udc {
>>       unsigned            active_suspend:1;
>>       u8                addr;
>>       struct at91_udc_data        board;
>> -    struct clk            *iclk, *fclk;
>> +    struct clk            *iclk, *fclk, *uclk;
>>       struct platform_device        *pdev;
>>       struct proc_dir_entry        *pde;
>>       void __iomem            *udp_baseaddr;
>>
>
>