Re: [PATCH] mmc: dw_mmc: Supply clocks for both host and card.

[Jaehoon Chung]

Hi

Seungwon Jeon wrote:
> Hi, Mr Chung.
> 
> Do you have any feedback?
> I want to know how to manipulate clock for host or card on your test situation.

Yes. i used clock for them.

> I think there is no code for these clock in dw_mmc.
> Who do you think is responsible for enabling clock? Driver or platform?
> 
Right. there is no code for clock. So if we use that controller, need to add clock.
But i didn't sure that we need to get clock's name from platdata.

If we can define the clock source, it's good that define standard clksrc name.("dw_mmc").

Regards,
Jaehoon Chung

> Any opinion/advice are welcome.
> 
> Best regards,
> Seungwon Jeon.
> 
> 
> Seungwon Jeon wrote:
>> Hi, Mr Chung.
>>
>>> -----Original Message-----
>>> From: linux-mmc-owner@xxxxxxxxxxxxxxx [mailto:linux-mmc-
>>> owner@xxxxxxxxxxxxxxx] On Behalf Of Jaehoon Chung
>>> Sent: Thursday, June 30, 2011 3:55 PM
>>> To: Seungwon Jeon
>>> Cc: linux-mmc@xxxxxxxxxxxxxxx; cjb@xxxxxxxxxx; linux-
>>> kernel@xxxxxxxxxxxxxxx; Kyungmin Park
>>> Subject: Re: [PATCH] mmc: dw_mmc: Supply clocks for both host and card.
>>>
>>> Hi Mr.Jeon
>>>
>>> What means cclk_name/ cclk enable?
>>> Controlling card clock is possible?
>>> Sorry, i didn't understand...
>>> (My understanding is that if we set host clk, cclk is used with
>> host_clk.)
>>> Plz can you explain to me?
>> Yes, cclk is source clock for card I/O.
>> It can be different from Host operating clock(hclk).
>>
>> Best regards,
>> Seunwgon.
>>
>>
>>> Regards,
>>> Jaehoon Chung
>>>
>>> Seungwon Jeon wrote:
>>>> Add enabling clocks for both host controller and card.
>>>>
>>>> Signed-off-by: Seungwon Jeon <tgih.jun@xxxxxxxxxxx>
>>>> ---
>>>>  drivers/mmc/host/dw_mmc.c  |   33 ++++++++++++++++++++++++++++++++-
>>>>  include/linux/mmc/dw_mmc.h |    7 +++++++
>>>>  2 files changed, 39 insertions(+), 1 deletions(-)
>>>>
>>>> diff --git a/drivers/mmc/host/dw_mmc.c b/drivers/mmc/host/dw_mmc.c
>>>> index 10b6979..a524416 100644
>>>> --- a/drivers/mmc/host/dw_mmc.c
>>>> +++ b/drivers/mmc/host/dw_mmc.c
>>>> @@ -1797,6 +1797,24 @@ static int dw_mci_probe(struct platform_device
>>> *pdev)
>>>>  		goto err_freehost;
>>>>  	}
>>>>
>>>> +	host->hclk = clk_get(&pdev->dev, pdata->hclk_name);
>>>> +	if (IS_ERR(host->hclk)) {
>>>> +		dev_err(&pdev->dev,
>>>> +			"Failed to get hclk\n");
>>>> +		ret = PTR_ERR(host->hclk);
>>>> +		goto err_freehost;
>>>> +	}
>>>> +	clk_enable(host->hclk);
>>>> +
>>>> +	host->cclk = clk_get(&pdev->dev, pdata->cclk_name);
>>>> +	if (IS_ERR(host->cclk)) {
>>>> +		dev_err(&pdev->dev,
>>>> +			"Failed to get cclk\n");
>>>> +		ret = PTR_ERR(host->cclk);
>>>> +		goto err_free_hclk;
>>>> +	}
>>>> +	clk_enable(host->cclk);
>>>> +
>>>>  	host->bus_hz = pdata->bus_hz;
>>>>  	host->quirks = pdata->quirks;
>>>>
>>>> @@ -1806,7 +1824,7 @@ static int dw_mci_probe(struct platform_device
>>> *pdev)
>>>>  	ret = -ENOMEM;
>>>>  	host->regs = ioremap(regs->start, regs->end - regs->start + 1);
>>>>  	if (!host->regs)
>>>> -		goto err_freehost;
>>>> +		goto err_free_cclk;
>>>>
>>>>  	host->dma_ops = pdata->dma_ops;
>>>>  	dw_mci_init_dma(host);
>>>> @@ -1945,6 +1963,13 @@ err_dmaunmap:
>>>>  		regulator_put(host->vmmc);
>>>>  	}
>>>>
>>>> +err_free_cclk:
>>>> +	clk_disable(host->cclk);
>>>> +	clk_put(host->cclk);
>>>> +
>>>> +err_free_hclk:
>>>> +	clk_disable(host->hclk);
>>>> +	clk_put(host->hclk);
>>>>
>>>>  err_freehost:
>>>>  	kfree(host);
>>>> @@ -1983,6 +2008,12 @@ static int __exit dw_mci_remove(struct
>>> platform_device *pdev)
>>>>  		regulator_put(host->vmmc);
>>>>  	}
>>>>
>>>> +	clk_disable(host->cclk);
>>>> +	clk_put(host->cclk);
>>>> +
>>>> +	clk_disable(host->hclk);
>>>> +	clk_put(host->hclk);
>>>> +
>>>>  	iounmap(host->regs);
>>>>
>>>>  	kfree(host);
>>>> diff --git a/include/linux/mmc/dw_mmc.h b/include/linux/mmc/dw_mmc.h
>>>> index f3f68ee..56b3f27 100644
>>>> --- a/include/linux/mmc/dw_mmc.h
>>>> +++ b/include/linux/mmc/dw_mmc.h
>>>> @@ -47,6 +47,8 @@ struct mmc_data;
>>>>   * @cmd: The command currently being sent to the card, or NULL.
>>>>   * @data: The data currently being transferred, or NULL if no data
>>>>   *	transfer is in progress.
>>>> + * @hclk: Clock for host.
>>>> + * @cclk: Clock for card.
>>>>   * @use_dma: Whether DMA channel is initialized or not.
>>>>   * @sg_dma: Bus address of DMA buffer.
>>>>   * @sg_cpu: Virtual address of DMA buffer.
>>>> @@ -118,6 +120,8 @@ struct dw_mci {
>>>>  	struct mmc_request	*mrq;
>>>>  	struct mmc_command	*cmd;
>>>>  	struct mmc_data		*data;
>>>> +	struct clk		*hclk;
>>>> +	struct clk		*cclk;
>>>>
>>>>  	/* DMA interface members*/
>>>>  	int			use_dma;
>>>> @@ -218,6 +222,9 @@ struct dw_mci_board {
>>>>  	/* delay in mS before detecting cards after interrupt */
>>>>  	u32 detect_delay_ms;
>>>>
>>>> +	char *hclk_name;
>>>> +	char *cclk_name;
>>>> +
>>>>  	int (*init)(u32 slot_id, irq_handler_t , void *);
>>>>  	int (*get_ro)(u32 slot_id);
>>>>  	int (*get_cd)(u32 slot_id);
>>>> --
>>>> 1.7.0.4
>>>>
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